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Larson, Ann Michelle. "Selection for milk somatic cell count in laboratory mice". Thesis, Virginia Tech, 1988. http://hdl.handle.net/10919/44079.
Pełny tekst źródłaA bidirectional selection experiment for high and low somatic cell count (SCC) was conducted over 14 generations with two selected lines (high line = HSCC, low line = LSCC) of mice. Seven secondary traits (milk yield, total white blood cell count, percentage of phagocytic cells in blood, endotoxin challenge response, percentage of females littering, number of young born alive, and percentage of young surviving to weaning) were measured to examine correlated responses to selection for SCC.
Average response per generation for log2 SCC was small in both selected lines (HSCC = .0678 ±.0341, LSCC = .0384 ± .0390, P > .05). There was little per generation divergence between the selected lines (.0294 ± .0178, P > .05). Genetic and phenotypic selection differentials indicated that selection procedures did select the more extreme individuals for SCC, even though response to selection was poor.
Phenotypic correlations among SCC and the seven secondary traits were generally small, and near zero. Correlation coefficients ranged from -.17 to .17. Milk yield was negatively correlated with SCC (-.07, P < .05). The correlation between endotoxin challenge response and SCC was also negative (-.17, P < .05).
Components of genetic variance for SCC were estimated to explain the lack of selection response. Covariances between daughter and dam, and among full sibs were negative (-.1180 and -.0362, respectively). Analysis for offspring and maternal components for SCC yielded a negative estimate for the covariance between additive effects for the offspring and maternal components (-.1781). No biological explanation can be offered for its existence. Heritability from this same analysis was .05.
Master of Science
Broaddus, Brent A. "IMPACT OF SEASON AND HEAT STRESS ON SOMATIC CELL COUNTS". UKnowledge, 2001. http://uknowledge.uky.edu/gradschool_theses/180.
Pełny tekst źródłaRogers, Sheryle Ann. "The influence of somatic cell count on milk composition and milk product quality". Thesis, Queensland University of Technology, 1986. https://eprints.qut.edu.au/35983/1/35983_Rogers_1986.pdf.
Pełny tekst źródłaArcher, Simon C. "Influence of somatic cell count in heifers on lifetime milk yield and disease management". Thesis, University of Nottingham, 2013. http://eprints.nottingham.ac.uk/13747/.
Pełny tekst źródłaGreen, Martin Jeremy. "Clinical mastitis in dairy cows : studies of bacterial ecology and somatic cell count patterns". Thesis, University of Warwick, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.404860.
Pełny tekst źródłaRoveglia, Chiara. "Genetic and phenotypic aspects of production, conformation and somatic cell count traits in Italian Jersey cattle". Doctoral thesis, Università degli studi di Padova, 2018. http://hdl.handle.net/11577/3426342.
Pełny tekst źródłaLa razza Jersey Italiana (IJ) è apprezzata per la sua efficienza e l’alta qualità del suo latte all’interno del contesto lattiero-caseario nazionale. L'obiettivo generale della presente tesi è la caratterizzazione fenotipica e genetica della produzione di latte, della morfologia e della conta di cellule somatiche della JI al fine di fornire alcuni strumenti utili per migliorare l’attuale indice di selezione della popolazione (Indice Qualità Jersey, IQJ). Nel primo capitolo si confermano le peculiarità fenotipiche del latte di JI, ovvero un alto contenuto di grasso (5.18%), proteina (4.08%) e caseina (3.16%), che lo rendono adatto alla trasformazione casearia. Il valore medio di punteggio di cellule somatiche (SCS) è risultato piuttosto alto (3.35), il che suggerisce l’importanza di indirizzare gli sforzi verso una riduzione di questo valore attraverso il miglioramento del management aziendale e la selezione, diminuendo indirettamente la suscettibilità della JI alla mastite. In questo studio è stato investigato anche il contenuto di urea del latte di JI quale indicatore di efficienza alimentare. Nel secondo capitolo sono state stimate ereditabilità pari a 0.14, 0.21, 0.26, 0.24, 0.20 e 0.10 rispettivamente per la produzione di latte, il contenuto di grasso, proteina, caseina, lattosio e SCS nel latte di bovine IJ. Le correlazioni genetiche tra SCS e i costituenti del latte sono risultate negative, e la più forte è stata stimata tra SCS e la percentuale di lattosio (-0.30). Il terzo capitolo ha stimato i parametri genetici di 20 caratteri morfologici in primipare di JI, includendo nuovi caratteri di rilievo funzionale ed economico, come la locomozione. Anche se le ereditabilità stimate per i caratteri morfologici sono risultate generalmente basse o moderate (da 0.04 a 0.32), la variabilità genetico-additiva ha suggerito la possibilità di intervenire con la selezione per migliorare geneticamente alcuni aspetti funzionali della razza. Le correlazioni più forti sono state stimate tra il punteggio di locomozione e i caratteri legati ad arti e piedi, ma anche tra punteggio di locomozione e la posizione dei capezzoli anteriori (0.97) e posteriori (0.88), suggerendo che un miglioramento della conformazione della mammella è associato a un potenziale perfezionamento della locomozione. Nel quarto capitolo sono stati definiti quattro caratteri alternativi derivati dalla conta di cellule somatiche (SCC) nel latte di JI rilevata nel corso dei controlli funzionali routinari (test-day, TD): 1) la media di TD SCS nei primi 150 giorni di lattazione; 2) la deviazione standard delle SCS nell’intera lattazione; 3) un carattere binario che indica l’assenza (0) o la presenza (1) di almeno un valore di TD SCC >400.000 cellule/mL nell’intera lattazione (Infezione); e 4) il rapporto tra il numero di TD SCC >400.000 cellule/mL e il numero totale di TD nell’intera lattazione (Severità). Sono stai stimati i parametri genetici di questi 4 caratteri alternativi delle SCC e le correlazioni genetiche gli aspetti produttivi e la morfologia della mammella. I risultati hanno mostrato la presenza di varianze genetiche ed ereditabilità dei caratteri alternativi delle SCC potenzialmente sfruttabili per migliorare la resistenza alla mastite. Infine, nel quinto capitolo sono stati stimati i valori economici (VE) delle SCS con due metodi differenti e in base al sistema pagamento latte-qualità di due caseifici italiani che producono Grana Padano. Tra i due metodi, quello basato sulla somma delle frequenze di ogni livello di SCS moltiplicato per la rispettiva penalità si è rivelato più penalizzante. Il sistema pagamento latte–qualità del caseificio 1 è risultato più rigido rispetto al caseificio 2. L’aumento delle penalità per livelli alti di SCS nel latte incentiva maggiormente ad includere SCS nell’indice di selezione della JI.
Testa, F. "INFLUENCE OF ATMOSPHERIC TEMPERATURE AND RELATIVE HUMIDITY ON BULK MILK SOMATIC CELL COUNT IN DAIRY HERDS". Doctoral thesis, Università degli Studi di Milano, 2012. http://hdl.handle.net/2434/168080.
Pełny tekst źródłaMartinkus, Nerijus. "Karvių melžimo operacijų įtaka somatinių ląstelių skaičiui piene". Master's thesis, Lithuanian Academic Libraries Network (LABT), 2008. http://vddb.library.lt/obj/LT-eLABa-0001:E.02~2008~D_20080318_142138-89478.
Pełny tekst źródłaData were collected from two dairy farms. On the farm A cows were milked using full automatised milking equipment „Milkmaster“. On the farm B cows were milked with „Interpuls“ milking equipment. The DeLaval milking system was supplied with automatic cluster remover. On dairy farms A and B cows were milked twice daily. The goal of our studies was to analyse consumption of main milking operations (cow udder preparation before milking, milking and over-milking) and their influence on milk somatic cell count. Were selected 20 cows in each farm. The duration of main milking procedures were recorded. Data on milk, fat and protein yields and somatic cell count were collected.The mean duration of pre-milking udder preparation was 42 s (farm A) and 46,03 s (farm B). Some cows were prepared only for 25,50 Afarm A) s, whereas the udder preparation comprised merely inadequate cleaning of teats. The maximum duration of over-milking was 41,10 (farm B).
Mazal, Guillaume. "Efeito da contagem de celulas somaticas do leite na fabricação do queijo prato". [s.n.], 2005. http://repositorio.unicamp.br/jspui/handle/REPOSIP/255198.
Pełny tekst źródłaDissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos
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Mestrado
Mestre em Tecnologia de Alimentos
Ekman, Torkel. "A study of dairy herds with constantly low or constantly high bulk milk somatic cell count, with special emphasis on management /". Uppsala : Swedish Univ. of Agricultural Sciences (Sveriges lantbruksuniv.), 1998. http://epsilon.slu.se/avh/1998/91-576-5434-4.gif.
Pełny tekst źródłaLembertas, Klaudijus. "Skirtingų veislių karvių melžimo savybių palyginimas". Master's thesis, Lithuanian Academic Libraries Network (LABT), 2014. http://vddb.library.lt/obj/LT-eLABa-0001:E.02~2014~D_20140618_233811-60078.
Pełny tekst źródłaThe aim of this thesis was to assess milking properties of cows of different breeds. Objectives of the paper: 1. Analyze the Lithuanian Black and White and Lithuanian Red cows milking qualities. 2. Determine lactation influence milking performance. 3. Determine the time of milking cows tested influence on milk yield and milk the average speed of the output. 4. To evaluate the farm impact of the milking properties. 5. Perform somatic cell count and milking performance correlation analysis. The scientific research was carried out between 2012-2014 at the Department of Animal Breeding of the Veterinary Academy of the Lithuanian University of Health Sciences and 2 dairy farms. Descriptive statistics: the average of investigated traits (M), standard errors were calculated using the EXEL and “R” (The R Project for Statistical Computing, 2012) statistical packages Milking properties were analyzed with the help of the device Lactocorder. In total 81 cows of Lithuanian black and white and Lithuanian red cattle breeds from two farms were analyzed. Lithuanian black and white cows constituted 71.6 percent, while Lithuanian red cows constituted 28.4 percent. According to lactation all analyzed cows were divided into the following three groups: lactation I, lactation II, lactation III and later. The first lactation cows constituted 6.1 % , the second lactation cows constituted 19.75 % and the group of cows of the third and later lactation was the largest and constituted 74.07 % . The... [to full text]
Nolan, Derek T. "AN EXAMINATION OF MILK QUALITY EFFECTS ON MILK YIELD AND DAIRY PRODUCTION ECONOMICS IN THE SOUTHEASTERN UNITED STATES". UKnowledge, 2017. http://uknowledge.uky.edu/animalsci_etds/71.
Pełny tekst źródłaBreen, James Eric. "An investigation of quarter and cow risk factors associated with the occurrence of clinical mastitis and elevated somatic cell count in U.K. dairy cows". Thesis, University of Bristol, 2007. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.443275.
Pełny tekst źródłaCortinhas, Cristina Simões. "Fornecimento de zinco, cobre e selênio orgânicos para vacas leiteiras e efeitos sobre a qualidade do leite e saúde da glândula mamária". Universidade de São Paulo, 2009. http://www.teses.usp.br/teses/disponiveis/10/10135/tde-16072009-112611/.
Pełny tekst źródłaThe general objectives of this study were to evaluate the effect organic zinc (Zn), copper (Cu) and selenium (Se) supplementationto dairy cows on milk quality, mammary gland health and feed intake. The specific objectives were to evaluate: the somatic cell count (SCC), clinical and subclinical mastitis prevalence, milk production and composition during the first 80 days of lactation; the superoxide dismutase (CuZnSOD), glutathione peroxidase (GSH-Px) and ceruloplasmin (CP) enzyme activity; the nutrients intake; Zn, Cu and Se plasmatic concentrations; changes in weight and body condition score. Nineteen dairy cows, with confirmed pregnancy, were selected by body weight (BW), body condition score (BCS), number of lactation, and milk yield in previous lactation, and randomly distributed among two groups to receive organic (n=9) or inorganic (n=10) sources of Zn, Cu and Se. The diets were formulated to meet the nutritional requirements of animals from 60 days before the expected date of calving up to 80 days of lactation. Every day, food samples and leftovers were collected for composition analysis. Milk samples was collected weekly after 15 days of lactation to determine the composition and CCS, on days 1 and 7 of lactation, and when a mastitis clinical case was diagnosed for microbiological culture. Blood samples were collected on -60, -21, 1, 21, 40 and 80 days of the experimental period for CuZnSOD, GSH-Px, and CP analysis. For plasma concentrations of Zn, Cu and Se blood samples were collected at 60 days before calving, and at 1st, 40th and 80th days of lactation. Assessments of body condition score (BCS) and body weight (BW) were performed at the beginning and at the end of the experiment, the day of calving, and once a week throughout the experimental period. The incidence (new cases) and total number of subclinical mastitis cases was lower for the group of cows fed organic Zn, Cu and Se in comparison with animals that received the inorganic sources. The SCC during the first 80 days of lactation was lower (P = 0,056) for the group fed organic Zn, Cu and Se. There were no effects of Zn, Cu and Se organic supply on concentrations of CuZnSOD, GSH-Px and CP, Zn, Cu and Se plasma, production and composition of milk, consumption of nutrients, BW, BCS and changes on BCS. It was observed effect of source on BW changes (P=0,024).
Swartz, Alexander Ogden. "SPECIAL PROBLEMS IN AGRICULTURAL ECONOMICS". UKnowledge, 2019. https://uknowledge.uky.edu/agecon_etds/77.
Pełny tekst źródłaTakahashi, Fabio Henrique. "Aplicação do controle estatístico de processo (CEP) como ferramenta para a melhoria da qualidade do leite". Universidade de São Paulo, 2011. http://www.teses.usp.br/teses/disponiveis/11/11139/tde-21092011-103622/.
Pełny tekst źródłaThis study aimed to employ statistical process control (SPC) as a tool to improve milk quality. The first objective of the study was to evaluate SPC as tool to identify non-natural variation of milk quality that are possible to be manipulated. In this study, data on milk production, somatic cell count (SCC), and total bacterial count (TBC) of 384 farms were used, provided by database of Clínica do Leite ESALQ/ USP in 2009. Natural effects (time of year and milk production) trough SCC and TBC variation were evaluated, and additionally, control charts for score cell somatic (SCS) and total bacterial count transformed (TBCt) were built aiming to identify sources of non-natural variations in a group of four farms. The variability of information was evaluated trough standard deviation estimator (sigma), calculated with basis of moving range. It was observed that time of year influenced significantly SCS and TBCt. The control charts, in each period, indicated signs of non-natural variation in SCS and TBCt in the group of herds evaluated. Furthermore, the control charts characterized the farms in statistical process control. The second study aimed to use SPC as a tool for identification and rating farms with larger probabilities of infraction on quality standard used by industry. Data of SCC and TBC from 452 farms, from January 2009 to March 2010, were used. The proportion of violation in quality standard, regarding the limits of SCC = 4000,000 cells/ mL and TBC = 100,000 CFU/ mL was calculated. Capability indices (Cpk) were calculated and farms were categorized into four classes of Cpk means and indices. Farms that presented larger means and deviation shoed superior frequencies of violation. Herds with means below the proposed limits of SCC and TBC represented, respectively, 25.05 % and 97.78 % of farms. However, proportion of farms that delivered milk consistently within the standards of quality evaluated (Cpk 1) represented 4.65 % and 35.17 % of farms for SCC and TBC, respectively. Therefore, application of SPC on farms is an additional tool for monitoring milk quality produced, the index Cpk can be used, by industries, associated with the current models to characterize milk quality from farms, since it identifies herds more consistent in producing quality-standard milk.
Brazauskas, Aurimas. "Lietuvos pieninių galvijų populiacijos karvių pieno elektrinio laidumo fenotipinis ir genetinis kintamumas bei ryšys su produktyvumu ir karvių sveikumu". Doctoral thesis, Lithuanian Academic Libraries Network (LABT), 2014. http://vddb.library.lt/obj/LT-eLABa-0001:E.02~2013~D_20140110_212435-31226.
Pełny tekst źródłaAim of the research: To examine indicators and factors of phenotypic and genetic variability of electrical conductivity of cows’ milk in Lithuanian dairy cattle popula¬tion and its relationship with selective traits. Main objectives of the research: 1. To examine the phenotypic variability of electrical conductivity of cows’ milk and to assess the influence of non-genetic factors in Lithuanian dairy cattle population. 2. To assess the phenotypic relationship between electrical conductivity of milk and productivity, milk composition, somatic cell count, milking parameters, reproduction and other factors. 3. To examine the influence of genetic factors on variability of elec¬trical conductivity of milk. 4. To determine the parameters of genetic variability of electrical con¬ductivity of milk and its genetic correlation with productivity, milk composition and quality, also to examine the expedience of using electrical conductivity of milk in Lithuanian dairy cattle breeding programs. Phenotypic and genetic variability of electrical conductivity of cows’ milk and its relationship with productivity, milk composition and health of cows in Lithuanian dairy cattle population was examined for the first time nationwide. A high heritability coefficient of electrical conductivity of cows’ milk and its genetic correlation with somatic cell count, as determined in the research, indicate that it is appropriate to use automated milking system data on the electrical conductivity of milk in... [to full text]
Rutaro, Hamid. "Milk quality analysis in Southwestern Uganda". Thesis, Kansas State University, 2015. http://hdl.handle.net/2097/19011.
Pełny tekst źródłaDepartment of Agricultural Economics
Vincent Amanor-Boadu
As the dairy industry faces the future, consumers’ demand for better milk quality and safety is increasing. Milk quality is of major interest to both consumers and dairy farmers alike. However, scientific data on milk quality in terms of somatic cell count (SCC) in Uganda and most developing countries has been lacking. This study used SCC to compare Southwestern Uganda’s milk quality against international standards. The study also sought to assess dairy farmers’ perceptions about milk quality. Milk samples were obtained from 100 farms in Mbarara and Kiruhura districts, the major cattle corridor in Uganda. The milk’s SCC was analyzed using a DeLaval DCC. A structured questionnaire surveyed farmers on milking procedures and milk-quality perception. Descriptive statistics and qualitative analysis was used to characterize and compare milk quality against the international benchmark. The study found that the 100 farms had an average SCC of 507,000 cells/ml. About 34% of farms in the study had SCC under 200,000 cells/ml, an indication of high-quality milk. Excluding 7% of the farms with SCC over 1,000,000 cells/ml, the remaining 93% had an average SCC of 276,000 cells/ml, a level comparable to international standards, well below the EU threshold of 400,000. The study also revealed that 98% of farmers considered milk quality as important or very important both to them and to the milk buyers. However, all farmers reported that they currently do not receive a milk-quality premium and are not penalized for poor quality. Seventy-nine percent of farmers reported the cooperative they belong to as their main source of information on management practices. An improved perception of milk quality both domestically and internationally will benefit Uganda’s dairy farmers and its dairy industry at large. Consumers must be assured that Uganda’s dairy industry, its government, industry stakeholders such as the Dairy Development Authority, the Uganda National Bureau of Standards, and the private sector place the utmost importance on the quality and safety of milk and other dairy products. New technologies to measure for SCC and strict food safety regulations will help improve the country’s milk-quality image, allowing Uganda’s dairy industry to tap into major milk export markets. Most developed countries have seen increased raw-milk quality or reduced SCC as a result of strong regulatory pressure.
Odensten, Martin. "Drying off the dairy cow : effects on metabolism and udder health /". Uppsala : Dept. of Animal Nutrition and Management, Swedish University of Agricultural Sciences, 2006. http://epsilon.slu.se/200618.pdf.
Pełny tekst źródłaOliveira, Naiara Aparecida Rodrigues de. "Classificação de rebanhos bovinos leiteiros baseado em risco para presença de Staphylococcus aureus e Streptococcus agalactiae na região da Zona da Mata de Minas Gerais". Universidade Federal de Juiz de Fora (UFJF), 2018. https://repositorio.ufjf.br/jspui/handle/ufjf/7093.
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A mastite está entre as doenças do gado leiteiro que mais causam prejuízos em todo mundo. Entre os agentes causadores estão os patógenos de origem contagiosa Staphylococcus aureus e Streptococcus agalactiae que mais contribuem para o aumento da Contagem de Células Somáticas (CCS) em rebanhos infectados.Desde a implantação da Instrução Normativa 51 ( IN 51/2002) do Ministério da Agriculutura Pecuária e Abastecimento(MAPA) em 2005, pouco se avançou em melhorias no parâmetro CCS dos rebanhos brasileiros, fazendo-se necessário o levantamento da situação das regiões a fim de traçar estratégias específicas para o controle da mastite e atendimento aos requisitos da legislação. O objetivo do presente estudo foi estabelecer uma classificação baseada em risco (dados probabilísticos) (risco) para presença de S. aureus e S. agalactiae em rebanhos bovinos leiteiros localizados Zona da Mata do Estado de Minas Gerais e vinculados a uma cooperativa. O trabalho foi realizado utilizando a população de bovinos leiteiros vinculados à Cooperativa dos Produtores de Leite de Leopoldina de Responsabilidade Ltda (LAC). A avaliação da dependência espacial entre as coordenadas geográficas dos rebanhos e a média geométrica anual da contagem de células somáticas foi realizada por meio de semivariogramas e os mapas de isolinhas por meio do método de Krigagem. Amostras para análise de CCS foram coletadas mensalmente.Para o estudo de prevalência foram selecionados aleatoriamente 43 rebanhos dos quais foram coletadas 3 amostras consecutivas de cada rebanho para análises microbiológicas durante o período de junho de 2016 a novembro de 2017. A análise espacial apresentou grau de dependência espacial e coeficiente de determinação fracos (GD<0,25; r2<0,13). A distribuição de frequência da CCS mostrou que apenas 23,3% dos rebanhos atendem ao limite de 400.000 células/mL . A prevalência de S. aureus foi de 93% a de S. agalactiae de 81,4% não diferindo estatisticamente entre si. Dos 43 rebanhos analisados, em tres (7%) não houve isolamento de S.aureus e de S. agalactiae, cinco (11,6%) apresentaram isolamento somente de S. aureus e 35 (81%) apresentaram isolamento de ambos patógenos. Não houve rebanhos com isolamento somente de S. agalactiae. Dos rebanhos sem isolamento destes agentes, a média de CCS foi de 224.000 células/mL, com isolamento somente de S. aureus a média de CCS foi de 447.000 células/mL, e para rebanhos com isolamento dos dois patógenos, S. aureus e S. agalactiae, 794.000 células/mL. Os rebanhos sem isolamento ou somente com isolamento de S. aureus estão associados a CCS inferior a 400.000 células/mL e rebanhos com isolamento de ambos os patógenos estão associados a CCS superior a 400.000 células/mL. A utilização da curva ROC para dados de CCS de rebanhos associados ao estudo de prevalência de S. aureus e de S. agalactiae permitiu classificar rebanhos em tres níveis de risco: baixo, médio e alto. A prevalência de S. aureus e de S. agalactiae entre rebanhos foi considerada alta para ambos patógenos, indicando que as medidas de controle para estes patógenos não estão sendo realizadas de maneira eficiente. Não foi observada diferença entre as prevalências de S. aureus e de S. agalactiae entre os rebanhos. Foi observada uma associação entre a CCS dos rebanhos e a presença de ambos os patógenos, permitindo desta forma uma classificação dos rebanhos.
Mastitis is among the most damaging diseases in dairy cattle worldwide. Among the causative agents are the pathogens of contagious origin Staphylococcus aureus and Streptococcus agalactiae that contribute most to the increase of Somatic Cell Count (SCC) in infected herds. Since the implantation of IN 51 in 2005, little progress was made in improving the SCC in the Brazilian dairy herds, therefore it is necessary to survey the mastitis situation of the regions in order to devise specific control strategies for mastitis control and compliance with the legislation requirements . The objective of the present study was to establish a risk - based classification (risk) for the presence of S. aureus and S. agalactiae in dairy herds located in the Zona da Mata of the State of Minas Gerais associated to a cooperative. The work was carried out using the population of dairy herds of Cooperativa dos Produtores de Leite de Leopoldina de Responsabilidade Ltda. (LAC).The evaluation of the spatial dependence between the geographical coordinates of the herds and the annual geometric mean of the somatic cell count was performed using semi-variograms and isoline maps using the Kriging method. Milk samples for SCC analyses were collected monthly. For the prevalence study, 43 herds were randomly selected and three milk samples from each herd were collected for microbiological analyzes during the period of June 2016 to November 2017. The spatial analysis presented degree of spatial dependence and weak determination coefficient (GD <0.25; r2 <0.13) The frequency distribution of CCS showed that only 23.3% of the herds met the limit of 400,000 cells / mL. The prevalence of S. aureus (93%) and of S. agalactiae (81.4%) did not differ statistically from one another. Of the 43 herds analyzed, three (7%) was no isolation of S. aureus and S. agalactiae, five (11.6%) had isolation only of S. aureus and 35 (81%) presented isolation of both pathogens. There were no herds with isolation of S. agalactiae. The mean SCC was 224,000 cels / mL, for the herds with absence of S. aureus and S. agalactiae, and 794.000 cels/ mL when the this two pathogens were present. The mean SCC for the herds with isolation only of S. aureus was 447,000 cells / mL,. The abcense or isolation only S. aureus herds are associated with CCS less than 400,000 cells / mL and herds with isolation of both pathogens associated with CCS greater than 400,000 cells / mL. The use of the ROC curve for herd CCS data associated to the study of S. aureus and S. agalactiae prevalence allowed the classification of the herds at three levels of risk: low, medium and high. The prevalence of S. aureus and S. agalactiae among herds was considered high for both pathogens, indicating that the control measures for these pathogens are not being carried out efficiently. There was no difference between the prevalences of S. aureus and S. agalactiae among the herds. An association was observed between the SCC of the herds and the presence of both pathogens, thus allowing a classification of the herds.
Filgueiras, Evando Alves. "Influência de um simbiótico na qualidade do leite e no intervalo de partos de vacas leiteiras". Universidade Federal de Goiás, 2013. http://repositorio.bc.ufg.br/tede/handle/tede/3425.
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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES
Biological additives, such as probiotics, prebiotics and digestive enzymes, as well as the combination of these components - commonly called synbiotics - are an alternative to improve livestock performance. In order to evaluate the effects in dairy cattle of a synbiotic containing microencapsulated bacteria, a meta- analysis was conducted using results obtained on commercial farms. Variables included milk production and quality, and reproductive performance. Data were collected on 22 farms feeding a commercial synbiotic composed of microencapsulated probiotics, prebiotics and fibrolytic enzymes (Biofórmula Leite®). All herds followed the manufacturer's recommended dosage of 2 g / animal / day. Information was collected on bulk tank milk production and quality (Somatic Cell Count - SCC,and contents of milk fat, protein and total solids), as well as reproductive data, such as inseminations and calving dates. These data were pooled for meta-analysis, which was performed according to the mixed models procedures recommended by St. Pierre. An analysis of variance was performed, considering the farm as a random variable and treatment as a fixed effect, with time period nested within farm. For each analysis, we used the GLM procedure of Minitab (Minitab, Inc., State College, PA, USA). A probability level of 0.05% was used to determine the statistical significance of each effect. Treatment with the synbiotic produced significant reductions in bulk tank SCC(-41%) , and in calving interval (- 73 days). There was no significant effect on the contents of fat, protein, and total solids in milk. The synbiotic additive used in this study proved to be an effective tool in the reduction of somatic cells in milk, as well as improving the fertility of animals.
Os aditivos biológicos, como os probióticos, prebióticos e enzimas digestivas, ou mesmo, a combinação destes componentes, comumente denominada de simbióticos, têm se mostrado como uma alternativa para melhorar o desempenho dos animais. Com a finalidade de observar os benefícios advindos dos simbióticos com bactérias microencapsuladas em bovinos de leite, objetivou-se nessa pesquisa, realizar uma meta-análise dos resultados obtidos em nível de campo com a utilização de um produto simbiótico no desempenho produtivo, reprodutivo e na qualidade do leite de vacas leiteiras. Os dados foram coletados em 22 propriedades que utilizam o simbiótico comercial Biofórmula Leite®, composto por probióticos, prebióticos e enzimas fibrolíticas. A dosagem utilizada em todas as propriedades seguiu a indicação do fabricante de 2 g/animal/dia. Foram coletadas informações de qualidade do leite (Contagem de Células Somáticas - CCS, teores de Gordura, Proteína e Sólidos Totais), foram registradas também as médias de produção dos animais ou quantidades entregues no laticínio, bem como os dados reprodutivos, como datas das inseminações e dos partos. Esses dados foram agrupados para realização de uma meta-análise, que foi realizada de acordo com os procedimentos de modelos mistos preconizados por St. Pierre. Foi realizada uma análise de variância usando o modelo misto, considerando a fazenda como variável aleatória e o tratamento como efeito fixo, e o período aninhado na fazenda. Para cada análise, foi utilizado o procedimento GLM do Minitab (Minitab, Inc., State College, PA, EUA). O nível de probabilidade de 0,05% foi utilizado para determinar a significância estatística de cada efeito. Foi observada uma redução significativa na média de CCS dos tanques (-41%), além de uma redução de 73 dias no IP. Não foi constatado efeito significativo nos teores de gordura, proteína, e sólidos totais do leite. O aditivo simbiótico utilizado neste estudo demonstrou ser uma ferramenta eficaz na redução de células somáticas no leite, bem como na melhoria da fertilidade dos animais.
Fernandez, Victoria Noel Vázquez. "Avaliação da qualidade do leite e de queijos produzidos pela agricultura familiar, em sistemas de produção ecológico e convencional, no leste do Rio Grande do Sul". reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2010. http://hdl.handle.net/10183/24999.
Pełny tekst źródłaThe dairy production of Brazil has been growing up yearly since the 1990 decade. In the whole country family agriculture has a high engagement in milk production, while in the State of Rio Grande do Sul, more than 80% of the milk delivered to the industry is originated in family properties. These properties adopt differentiated production systems in relation to the use of raw materials, as they could be conventional or ecological, and many times they try to add value through the manufacturing of milk to dairy products. This piece of work had the objective of evaluating the quality of milk produced through the conventional system (CONV) and ecological (ECO), and of homemade cheeses originated from family agriculture and to verify if the quality of these products is in accordance with the respective current regulations. The work was performed between October 2008 and September 2009, when 10 family agricultural UPL‟s (Dairy Production Units), located in the eastern region of Rio Grande do Sul were visited monthly. During these visits milk samples from the herds and cooling tanks from each one of the properties were collected and sent for chemical and physical analysis, counting of somatic cells and total bacterial count. During the months of February and July 2009 samples of the feed offered to the animals in each one of the properties were collected. These samples were subject of bromatology analysis to determine PB (Gross Protein), FDN (Neutral Detergent Fiber), and FDA (Acid Detergent Fiber). In June 2009 samples were taken from: water used during milking and homemade cheeses produced by these families. The milk from agricultural family presented average CCS (Somatic Cells Count) and CBT (Total Bacterial Count) above the values established by Regulatory Instruction Nº 51, while the lactose percentage was lower than expected. There was no significant difference between the evaluated milk quality parameters for the different systems, though the CBT presented a significant interaction in relation to the system/month, whereas a significant monthly variation was verified in the ECO. The bacterial counts were higher during the spring and summer months. During this period higher milk production was observed. Cheeses produced by the evaluated agroindustrial units and that were produced from raw milk presented inadequate microbiological quality according to standards established through Resolution RDC nº 12, thus considered inadequate for human consumption. The structure used by family agricultural labourers for cheese production presents deficiencies and inadequacies in all the properties studied during this work. In the evaluated situation there was no significant difference between the quality of milk produced through the different systems, ecological and conventional. The family agriculture presented problems related to the nutrition and hygienical handling that can impair milk quality, while the data in reference to CCS, CBT and ESD is more worrisome. In relation to the cheese and manufacturing practices used in the evaluated properties, it was clear and evident that the deficiencies in the thermal treatment of milk used in the production of high humidity cheeses influences directly the microbiological quality of these products, leaving the consumer‟s health under risk. The implementation of Good Manufacturing Practices would be important to help the control of contamination and possible intoxications.
Österman, Sara. "Extended calving interval and increased milking frequency in dairy cows : effects on productivity and welfare /". Uppsala : Dept. of Animal Nutrition and Management, Swedish Univ. of Agricultural Sciences, 2003. http://epsilon.slu.se/a383.pdf.
Pełny tekst źródłaSterrett, Amanda E. "Management and technology solutions for improving milk quality". UKnowledge, 2013. http://uknowledge.uky.edu/animalsci_etds/27.
Pełny tekst źródłaŽilinskaitė, Giedrė. "Veislės įtaka karvių pieno sudėčiai ir kokybei". Master's thesis, Lithuanian Academic Libraries Network (LABT), 2013. http://vddb.laba.lt/obj/LT-eLABa-0001:E.02~2013~D_20130618_095050-69037.
Pełny tekst źródłaThe objective of the work: Estimate the influence of the breed on cow's milk productivity, milk constitution and quality. The task of the work: Estimate the influence of breed all controlled for Lithuanian dairy cattle population cows’ productivity, milk constitution and quality according somatic cells; estimate the influence of breed research black and white cows cattle productivity, milk constitution and it quality according somatic cells. Dairying is one of priorities in the development of agriculture. Milking capacity, the constitution of milk, also its quality depend on genetic and non-genetic factors. The biggest influence over milk indicators is made with fodder and feeding ( it makes 50-60 per cent), genetic factors ( it makes 25-27 per cent), the remaining part depends on cattle keeping and supervision technologies. There are 16 cow breeds in Lithuania. Mostly red and black and white breed cows are raised in Lithuania. Lithuanian black and white cows milking capacity is bigger than of red and red and white ones, however the quantity of fat and protein is higher in red and red and white group of cows. From the control of productivity and accounting research the most productive from black and white cows is Swedish black and white cattle breed, while from red ones is Estonian red breed cows. The biggest quantity of protein and fat is noticed in the milk of Angler breed cows. The highest level of protein is found in Dutch black and white cows’ milk, white the... [to full text]
Salaberry, Sandra Renata Sampaio. "Fatores de virulência de Staphylococcus spp. e viabilidade celular na mastite subclínica de cabras". Universidade de São Paulo, 2014. http://www.teses.usp.br/teses/disponiveis/10/10134/tde-04122014-113107/.
Pełny tekst źródłaSubclinical mastitis in goats is mainly caused by Staphylococcus spp., coagulase-negative staphylococci (CNS) is the most frequent pathogens and S. aureus, the most researched specie of staphylococci. Thus, little is known about the pathogenicity of SCN and other coagulase-positive staphylococci (CPS), beyond the S. aureus. There are few studies on the variation of cell viability in subclinical mastitis of goats. The aim of the present study was to determine the virulence factors of adhesion and biofilm production of Staphylococcus spp. strains isolated from milk samples of goats, verifying for possible associations with cell viability. To collect samples, firstly, was performed a physical examination of the mammary gland, with subsequent tests for mug of black background and California mastitis test (CMT). Three aliquots of milk were collected: microbiological analysis, somatic cell count (SCC) and cell viability. Identification, antibiotic susceptibility testing and PCR (polymerase chain reaction) were performed of Staphylococcus spp. isolated from milk samples. Virulence genes researched in PCR were: cna, eno, ebpS, fnbA, fnbB, fib and bap. Evaluation of CCS, using flow cytometry equipment, and cell viability, after centrifugation of milk samples and visualization the cells in the microscope using Trypan blue dye, were performed. The results were: from 122 samples with bacterial growth, 110 (90.2%) were identified as Staphylococcus spp., 90 (73.8%) of CNP and 12 (16.4%) of the CNP. The most isolated staphylococci species were: S. epidermidis (24.55%), S. lugdunensis (15.40%) and S. intermedius (13.64%). Samples showed higher resistance to antimicrobials: penicillin (81.8%), oxacillin (60.0%) and ampicillin (55.5%). We observed higher sensitivity to: enrofloxacin (99.1%), erythromycin (98.2%), gentamicin (98.2%) and vancomycin (98.2%). Regarding virulence factors researched, positive samples were found for all genes, except fnbB gene: eno (53.6%), bap (43.7%), ebpS (19.1%), fnbA (18.2%) and fib (16.4%). More than one gene were detected in some strains, with the most frequent associations were bap/eno in CNS and ebpS/eno/fib/fnbA in CNP. The values of SCC of milk samples with isolation of Staphylococcus spp., CNS and CNP were higher than samples without bacterial isolation and the isolation of strains with combination of ebpS/eno/fib/fnbA genes showed higher SCC than bap/eno. Regarding cell viability, samples with isolation of Staphylococcus spp. showed higher cell viability than samples without bacterial isolation and there was no association of the genes identified in strains with cell viability. In conclusion, eno and bap genes were more frequent in Staphylococcus spp. strains, eno and bap genes were mostly found in isolated CNS and ebpS, fib and fnbA genes were more detected in CNP. Cell viability was higher in samples with isolation of Staphylococcus spp. compared those without bacterial isolation and there was no association between the virulence factors of Staphylococcus spp. strains and cell viability.
Rodrigues, Ana Carolina de Oliveira. "Identificação bacteriana a campo da mastite bovina para orientar protocolos de tratamento". Universidade de São Paulo, 2008. http://www.teses.usp.br/teses/disponiveis/11/11139/tde-17072008-142038/.
Pełny tekst źródłaThe present thesis investigated the diagnosis and treatment of bovine mastitis by using a simple test for somatic cell count, on-farm bacteriological culture and guided treatment protocols. To rapidly determine SCC, Somaticell® test was used on milk samples having the results compared to electronic count and evaluated by sample type and reader. The Somaticell test correctly determined the SCC in fresh milk samples of mammary quarters. The correlation between Somaticell and electronic SCC was 0.92, being kappa coefficient equals to 0.82. This test presented good reliability to determine intramammary infections using a threshold of 205.000 cells/mL (sensitivity = 91.3% and specificity = 96.0%) and showed greater SCC in samples containing major mastitis pathogens. Minor intra-individual variation was detected when performing the test. Probably, the homogenization procedure of the test is the most likely explanation for the observed variation. However, the final analysis indicated that this variation was not significant and did not affect the amount of samples classified as having subclinical mastitis. Milk samples preserved at 4 ºC up to 5 hours did not change test results. Nevertheless, frozen or bronopol preserved samples were not suitable for this test. Clinical mastitis data indicated that infections caused by Gram positive bacteria were mainly seen on clinical cases with visual milk abnormalities and udder edema of clinical recurrent animals showing monthly average SCC greater than 200,000 cells/mL. In contrast, clinical mastitis caused by Gram negative bacteria was frequently associated with systemic signs in high producing cows. In addition, mastitic samples without bacterial growth in the laboratory did not present a defined pattern in relation to mastitis grade and animal characteristic. The on-farm bacteriological culture using Azide Blood Agar Base, MacConkey Agar and Vogel-Johnson Agar, showed adequate recovery of mastitis causing pathogens. In 79.3% of the cultures (n = 203) the on-farm results agreed with the standard laboratory culture. Interestingly, the concordance rate was affected by the number of colony forming units in the milk sample. The sensitivity and specificity of on-farm culture were 83.0 and 76.5%, respectively. These results were positively influenced by growth of Gram positive bacteria and negatively influenced by growth of Gram negative bacteria and samples with no growth. The use of fresh milk samples in on-farm culture seemed advantageous for bacterial recovery, although premature plate reading of bacterial growth and simplicity of this methodology might reduce its accuracy. Mastitis treatment guided by on-farm culture showed an overall bacteriological cure rate of 69.7%. In the majority of quarters, SCC remained elevated within 21 days after detection of clinical mastitis. Gram negative bacteria presented greater cure rates. On the contrary, Staphylococcus aureus mastitis displayed the lowest cure rate even by using extended antibiotic treatment. Intramammary antibiotic treatment did not show effect on cure rates of grade 1 and 2 clinical mastitis caused by Gram negative bacteria or with negative growth in the on-farm culture.
Santos, Marcos Veiga dos. "Correlação entre ácido ascórbico plasmático, contagem de células somáticas no leite e o perfil metabólico de vacas secas e em lactação". Universidade de São Paulo, 1998. http://www.teses.usp.br/teses/disponiveis/10/10135/tde-03042003-100927/.
Pełny tekst źródłaDairy cows are totally dependent of endogenous synthesis of ascorbic acid to meet their requirements. Therefore, any condition that decrease the availability of ascorbic acid precursors like glucose and galactose, may result in insufficient synthesis of ascorbic acid. High producing dairy cows may be predisposed to subclinical ascorbic acid deficiency due to the elevated demand for glucose to lactose synthesis by mammary gland. The purpose of this study was to determine the effects of stage of lactation and number of lactations on plasma ascorbic acid concentration, and to establish the association between plasma ascorbic acid level and glucose, insulin, non-esterified fatty acids (NEFA), beta-hydroxybutyrate (BHBA), aspartate-amino transferase (AST), milk somatic cell count (SCC), milk yield and body condition score in dairy cows. One hundred and ninety three dairy cows (153 lactating and 40 dry cows) from 3 different herds were used in this study. Animals were randomly selected, and assigned to 5 groups according the stage of lactation (stage 1: 1-28 days; stage 2: 29-56 days; stage 3: 57-140 days; stage 4: 141-280 days and stage 5: dry cows) and the number of lactation (primiparous or multiparous). Blood samples were taken for ascorbic acid determination by HPLC technique. Statistical analysis was performed using the SAS program. Statistical significance was declared at the 5% level. Average plasma ascorbic acid concentration (mg/L) for Group 1 to 5 were 2.67; 2.60; 2.46; 2.63 and 2.60, respectively, and 2.63 and 2.52 for primiparous and multiparous cows. A negative correlation was observed between ascorbic acid and both glucose and NEFAs and a positive correlation between ascorbic acid and milk yield. No correlation was found between ascorbic acid and other parameters. Results of this study demonstrated that plasma ascorbic acid concentration did not change in response to stage of lactation and number of lactations and eventhough plasma ascorbic acid was correlated to glucose, NEFAs and milk yield, it was not possible to identify the factor that determine ascorbic acid variability in dairy cows.
García, Andrea Vásquez. "Avaliação, isolamento e identificação dos principais microrganismos causadores de mastite subclínica em búfalas". Universidade de São Paulo, 2014. http://www.teses.usp.br/teses/disponiveis/74/74132/tde-24092014-134806/.
Pełny tekst źródłaThe exploration of buffaloes for milk production and dairy products is an activity that has grown in recent years in Brazil. Buffaloes present similar health problems for cattle. The objective of this study was to determine the isolation and the phenotypic and molecular characterization of the main microorganisms causing of subclinical mastitis in buffaloes (Bubalus bubalis) on four dairy farms in the central region of state of Sao Paulo, Brazil, through testing somatic cell count (SCC), standard plate count (SPC), phenotypic and biochemical characterization of the microorganisms isolated and confirmed by PCR technique, as well as to evaluate the profile of bacterial sensitivity to antibiotics given for the major pathogens commonly isolated in cases of subclinical mastitis in buffaloes Twenty milk samples from lactating buffaloes were analyzed in 2013 that have presented SCC above 200,000 cells/mL. Based on the Instruction Normative N°62 of 2011 of the Ministério da Agricultura, Pecuária e Abastecimento (MAPA) which deals with microbiological standards for bovine milk, of the 20 samples analyzed in this study, only 1 (5%) was within the established standard (1x104 CFU/mL) with a variation in the results of 1.0x104 CFU/mL to 57.7x105 CFU/mL. The CCS showed a median of 721,000 cells/mL in the milk (minimum value; 205,000, maximum value: 2,264,000), indicating the presence of subclinical mastitis. It was found that agents with higher frequency of isolation were Staphylococcus epidermis (17%), Staphylococcus aureus (15%) and Bacillus spp. (14%). The PCR assays confirmed the results obtained with isolating in the phenotypic and biochemical characterization of Staphylococcus aureus, Staphylococcus epidermidis, Streptococcus spp. and Escherichia coli. With the realization of the antibiogram was possible to draw a profile of resistance of different antibiotics tested. The study of bacterial sensitivity showed that for higher sensitivity (100%) of Staphylococcus aureus and Staphylococcus epidermidis to antibiotics gentamicin and vancomycin; for the genus Streptococcus spp. to gentamicin and oxacillin and for Escherichia coli to ampicilina.
Freitas, Fernanda Antunha de. "Proteinograma de leite de vacas com mastite subclínica em função do escore de células somáticas e de microrganismos isolados e identificados por microbiologia convencional". Universidade Federal de Goiás, 2017. http://repositorio.bc.ufg.br/tede/handle/tede/7867.
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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES
Intramammary infections can be triggered by a large number of etiologic agents and may lead to changes in the mammary gland parenchyma, composition of milk and reduction of milk production. The aim of the present study was to evaluate the electrophoretic profile of cow milk proteins by the analysis of microfluidic electrophoresis lab-on-a-chip and its alterations in relation to milk samples with different SCC and the presence of pathogenic microorganisms. A total of 101 milk samples were collected from cows from two dairy farms located in the state of Goiás. Microbiological analyzes, somatic cell counts, centesimal composition and microfluidic electrophoresis were performed. For the correlation test between the protein profile and the SCC the samples were stratified into five groups of somatic cells scores. The data were analyzed using descriptive statistics through the analysis of variance and graphical representations. There was a significant increase in the value of the protein component in relation to the SCS 1 and 3, 1 and 4 and 1 and 5. It was also possible to observe statistical difference in the results of the Lactose component when comparing SCS 1 and 3 and SCS 3 and 4. The evaluation of the variable "Concentration" of milk proteins was possible to observe differences in the concentration values of SCS. Statistical difference was also observed for concentration of α-LA when compared SCS 1,2 and 3 to SCS 5; For IgG, SCS samples 4 and 5 showed different concentrations of SCS samples 1,2 and 3; the LF protein showed different results among samples from the SCS 1 and 5. The microorganisms identified were Staphylococcus spp. Negative Coagulase, Arcanobacterium pyogenes, Streptococcus spp., Staphylococcus aureus, Bacillus spp. and yeast. There is no statistical evidence that the mean concentration of the proteins present in milk samples is different between any groups of samples with different microorganisms evaluated. In the comparison between the concentrations of each protein expressed in each group of samples, a statistical difference was observed in the concentration of α-lactalbumin between samples from the yeast group and samples without bacterial growth. It was concluded that whey proteins of high abundance have their concentration decreased with the occurrence of mastitis; Defense proteins such as Lactoferrin, Lactoperoxidase, IgG and IgM have their concentration increased when comparing milk samples from cows with subclinical mastitis and milk samples from healthy cows; Lactoferrin and IgG proteins are potential targets for identifying cows with subclinical mastitis in milk samples and may be considered biomarkers. It was also concluded that intramammary infections caused by the microorganisms identified in the present study do not alter the concentration of whey proteins of lactating cows; Milk samples with high SCC may present negative results for microbiological culture; The SCN showed higher frequency of isolation in milk samples from lactating cows, revealing opportunistic and saprophytic characteristics; And infection of the mammary gland caused by yeast causes a significant increase of the α-lactalbumin protein.
As infecções intramamárias podem ser causadas por um grande número de agentes etiológicos e cursar com alterações no parênquima da glândula mamária, na composição no leite e no volume de leite produzido. Considerando o exposto, objetivou-se com o presente estudo avaliar o perfil eletroforético de proteínas de amostras de leite de vacas por meio da análise de eletroforese microfluídica lab-on-a-chip e suas alterações em relação às amostras de leite com diferentes CCS e à presença de microrganismos patogênicos. Foram coletadas 101 amostras de leite de vacas provenientes de duas propriedades leiteiras localizadas no estado de Goiás. Foram realizadas análises microbiológicas, contagem de células somáticas, composição centesimal e eletroforese microfluídica lab –on – a chip. Para o teste de correlação entre o perfil de proteínas e a CCS as amostras foram estratificadas em cinco grupos de Escores de Células Somáticas. Os dados foram analisados utilizando estatística descritiva por meio do teste de análise de variância e representações gráficas. Verificou-se um aumento significativo no valor do componente proteína em relação aos ECS 1 e 3, 1 e 4 e 1 e 5. Também foi possível observar diferença estatística nos resultados do componente Lactose quando se comparou os ECS 1 e 3 e 3 e 4. Na avaliação descritiva da variável “Concentração” das proteínas do leite foi possível observar diferenças nos valores das concentrações em função do ECS. Observou-se também diferença estatística para os resultados obtidos para as proteínas α-LA, quando comparados os ECS 1,2 e 3 e o ECS 5; para a IgG, as amostras de ECS 4 e 5 apresentaram concentrações diferentes das amostras dos ECS 1,2 e 3; e a proteína LF, apresentou resultados diferentes entre as amostras de ECS 1 e 5. Os microrganismos isolados e identificados que apresentaram crescimento nas amostras coletadas foram bactérias coagula negativo do gênero Staphylococcus, Arcanobacterium pyogenes, Streptococcus spp., Staphylococcus aureus, Bacillus spp. e leveduras. Não há evidência estatística de que a média da concentração das proteínas presentes nas amostras de leite de vacas seja diferente entre nenhum grupo de amostras com diferentes microrganismos avaliados. Na comparação entre as concentrações de cada proteína expressa em cada grupo de amostras, verificou-se diferença estatística na concentração da proteína α- lactalbumina entre as amostras do grupo de leveduras e amostras sem crescimento bacteriano. Concluiu-se que proteínas de alta abundância do soro de leite tem sua concentração diminuída em função da severidade da mastite; proteínas de defesa, como Lactoferrina, Lactoperoxidase e IgG e IgM têm aumento em suas concentrações quando se comparam amostras de leite de vacas com mastite subclínica e amostras de leite de vacas sadias; as proteínas Lactoferrina e IgG constituem alvos em potencial para identificar vacas com mastite subclínica a partir de amostras de leite, podendo ser consideradas biomarcadores. Concluiu-se ainda que infecções intramamárias causadas pelos microrganismos isolados e identificados no presente estudo não alteram a concentração das proteínas no soro de leite de vacas em lactação; as amostras de leite com altas CCS podem apresentar resultado negativo para cultura microbiológica; os SCN apresentaram maior frequência de isolamento em amostras de leite de vacas em lactação, revelando características de oportunistas e saprófitas; e a infecção da glândula mamária causada por leveduras provoca aumento significativo da proteína α-lactoalbumina.
Fernandes, Andrezza Maria. "Avaliação do iogurte produzido com leite contendo diferentes níveis de células somáticas". Universidade de São Paulo, 2004. http://www.teses.usp.br/teses/disponiveis/74/74131/tde-22042004-160853/.
Pełny tekst źródłaThe aim of the present study was to evaluate physical, chemical and microbiological characteristics, as well as proteolysis, lipolysis and viscosity of plain stirred yoghurt produced from whole milk with somatic cell counts (SCC) at levels of < 400,000 cells/mL, 400,000-800,000 cells/mL and > 800,000 cells/mL. Each milk treatment was obtained from selected cows, according to its SSC status and milk composition. Yoghurts were produced after standardisation of milk total solids (TS), followed by pasteurisation (90ºC, 15 minutes), addition of starter culture, incubation (42ºC, approx. 3 hours) and packaging. Yoghurts were stored at 5ºC, and quality evaluation was conducted in samples collected on days 1, 10, 20 and 30 after production. Manufacturing procedures were repeated for six times, from March to August/2003. Yoghurt analyses included: pH, acidity, fat, protein, TS, solids non-fat (SNF), total nitrogen (TN), non-casein nitrogen (NCN) and non-protein nitrogen (NPN), free fatty acids (FFA), apparent viscosity, lactic bacteria counts and coliforms at 30 and 45ºC. There were no differences (P > 0.05) in physical, chemical and microbiological parameters of milk and yoghurt among treatments. Proteolysis, as estimated by TN NCN / TN NPN relation, was constant for all treatment yoghurts (P > 0.05). Viscosity of high SCC yoghurt (> 800,00 cells/mL) increased (P < 0.05) on 10, 20 and 30 days storage, and a positive correlation (P < 0.05) with SCC was observed on days 20 and 30. FFA content was higher (P < 0.05) on days 1 and 30 of storage, and besides there was a positive correlation (P < 0.05) between SCC and FFA levels on the same days of storage. Results indicate that high SCC milk do not affect proteolysis of yoghurt, although it increases viscosity and lypolisis during storage for 30 days.
Kretschmer, Emily R. "Efficacy of the PortaSCC® milk test to estimate somatic cell count (SCC) and detect subclinical mastitis in sheep, and the effect of cell counting method, sampling day, and udder health status on SCC and constituents in sheep mild". abstract and full text PDF (free order & download UNR users only), 2007. http://0-gateway.proquest.com.innopac.library.unr.edu/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:1447606.
Pełny tekst źródłaSant'Anna, Aline Cristina. "Fatores causais do grau de limpeza de vacas leiteiras e suas relações com a contagem de células somáticas/". Jaboticabal : [s.n.], 2009. http://hdl.handle.net/11449/96598.
Pełny tekst źródłaAbstract: The aims of this study were to describe the variation on dairy cow's body hygiene conditions over time and according to the seasons, verify if the cows are consistent for hygiene, to identify the relationship between the cleanliness score and the cow's behavior, particularly those related to land use and thermoregulation and finally, to associate the cow's cleanliness score and their milk somatic cell count (SCC). During nine months the body hygiene was accessed for lactating cows from two Brazilians commercial farms, a total of 3554 observations for 545 animals. The hygiene was expressed as a four points cleanliness score. To evaluate the relationship between the cleanliness score and behavior, behavioral categories of posture, positioning and activities were assessed for at least 46 dairy cows in two months of dry season and two of rainy season. The SCC was accessed for 404 cows, a total of 2218 data. Individual variation was found in the cow's hygiene, and in the dry season the animals maintained cleaner than in the rainy season. Although the variation, approximately half of the cows are consistent for their hygiene - clean for the majority. The body hygiene was associated with the cow's behavior. To explain this association the behavioral categories can be summarized as: behaviors that determine the directly transfer of dirt to the cows' body (to lie down in a mud surface), while others behaviors are indirectly related to the transfer of dirty (lie down in a shaded place). In addition the behaviors as rumination and feeding does not determine the direct transfer of dirt to the body, however, these may be indicators of heat tolerance and the individual social ranking in the group, and differences in these characteristics are related to exposure of animals to certain dirty areas. The cleanliness score have effect on SCC (F = 4.85; df = 3; p < 0,01), and good hygiene condition... (Complete abstract click electronic access below)
Orientador: Mateus José Rodrigues Paranhos da Costa
Coorientador: Marcelo Simão da Rosa
Banca: Luciandra Macedo de Toledo
Banca: Maria Imaculada Fonseca
Mestre
Reis, Carolina Barbosa Malek dos. "Avaliação da contagem de células somáticas do leite como indicador da ocorrência de mastite em vacas Gir". Universidade de São Paulo, 2010. http://www.teses.usp.br/teses/disponiveis/10/10135/tde-21092010-160553/.
Pełny tekst źródłaThe aim of this study was to determine the sensibility and specificity of somatic cell count (SCC) threshold in Gyr cows to diagnosis the subclinical mastitis caused by primary and secondary pathogens, and to evaluate the effect of herd, cows, month, mammary quarter, intramammary infection, type of microorganism and their interactions on logSCC and milk composition. The hypothesis to be tested was that the SCC threshold to detection of subclinical mastitis is the same for Holstein and Gir cows. A total of 221 lactation Gir cows from three commercial dairy farms was selected. Composed and quarter individual milk samples were collected once a month, during one year for SCC, milk composition and bacteriological analysis. The mammary quarter and the cow were considered experimental units. To determine the sensibility, specificity and odds ratio (OR) from SCC threshold to identify the infected quarters four values of SCC: 100, 200, 300 and 400 (x 103 cells/mL) were used. It was also evaluated the correlation between SCC and milk composition. There was no effect of herd on logSCC in individuals and composed samples, but cow nested within herd was major factor responsible for the logSCC variation. The month of sampling presented significant effect on logSCC and milk composition in both experimental units. The intramammary infection presence affected negatively the milk composition, except of fat concentration. Higher lactose, protein and non-fat solids (NFS) percentages were found in negative samples and higher logSCC were observed in infected samples. The SCC threshold of 100 x 103 cells/mL presented the major sensibility and negative predictive value for subclinical mastitis detection. The threshold of 200 x 103 cells/mL had higher chance to have mastitis than the threshold of 100 x 103 cells/mL. It was observed a negative correlation between SCC with lactose and NFS; but the correlation was positive between SCC with fat and protein in mammary quarters and cow level. Milk composition was influenced by SCC, once the lactose and NFS percentages decreased in samples with high SCC and the protein and fat concentration increased.
Cortinhas, Cristina Simões. "Qualidade do leite cru e práticas de manejo em fazendas leiteiras". Universidade de São Paulo, 2013. http://www.teses.usp.br/teses/disponiveis/10/10135/tde-21082014-111709/.
Pełny tekst źródłaThe overall objectve of this study was to evaluate risk factors associated with management practices and hygienic raw milk quality, and to caracterize the farmer\'s knowledge and opinions about mastitis control and milk quality. The specific objectives were to evaluate the risk factors associated with hygienic milk quality, to determine the effect of mastitis pathogens on raw milk quality and to assess the association between framers knowledge about mastitis control and somatic cell count (SCC) of bulk tank. Therefore, we proposed three experiments. For experiment 1, to evaluate management practices associated with hygienic quality of raw milk in dairy farms, 120 dairy herds were selected according to the geometric mean of the total bacterial count (TBC) from 10 milk samples collected during two consecutive months, which were distributed in two groups: high TBC (1.11 x104 CFU / mL, n = 60) and low TBC (4.4 x103 CFU / mL, n = 60). After selection of herds, milk samples were collected weekly for two months to perform analyzes of TBC, preliminary incubation count (PIC), laboratory pasteurization count (LPC), coliform count (CC), somatic cell count (SCC) and fat, protein and total solids concentrations. After laboratory analysis, 63 herds were visited for on-farm data collection by a questionnaire about: a) general aspects of farm management; b) milking management; c) milking equipment and utensils cleaning procedures; d) mastitis control; e) udder cleaning conditions. For experiment 2, to evaluate the knowledge and opinions of dairy farmers about mastitis control and milk quality, 63 herds were selected and distributed according to geometric means of SCC (8 weekly milk sampling during two consecutive months) into three groups: a) low SCC: ≤ 250,000 cells / mL (n = 16); b) medium SCC: >250,000 ≤ 400,000 cells / mL (n = 24); c) high SCC:> 400,000 cells / mL (n = 23). Previously formulated questionnaires were submitted to the herd manager, with questions about the following topics: socioeconomic characteristics, knowledge about SCC, TBC, mastitis and mastitis prevention practices. For experiment 3, to evaluate the association between mastitis pathogens, SCC and TBC, 90 herds were selected based on the SCC of 10 milk samples collected during two consecutive months, to compose the following groups: a) ≤ 250,000 cells / mL (n = 30), b) >250,000 ≤ 600,000 cells / mL (n = 30), c)> 600,000 cells / mL (n = 30). Bulk Tank milk samples were collected every 15 days for a period of three months, for Staphylococcus aureus count, Streptococcus agalactiae count, coagulase-negative staphylococci count, environmental streptococci count, Escherichia coli count, coliform count, TBC, SCC and fat, protein and total solids concentrations. The high amount of organic matter in the bulk tank outlet valve is a risk factor for the raw milk hygienic quality, the use of pre and post teat dipping is associated with a reduction of major indicators of raw milk hygienic quality and the presence of suckling calves before milking was associated with increased TBC, PIC and CC. Other social and economical factors, such as the milk as main economic activity in the farm, type of milking procedures used, the use of methods for mastitis detection and knowledge about legal requirements for SCC and TBC were correlated with CCS in bulk tank milk. Additionally, high Streptococcus agalactiae counts is associated with reduced bulk tank milk quality because of increased SCC.
Martello, Leonir. "Avaliação da implantação das boas práticas agropecuárias para a qualidade e segurança do leite de uma cooperativa do Estado do Rio Grande do Sul". reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2017. http://hdl.handle.net/10183/172875.
Pełny tekst źródłaMilk food chain has an important role in the economic and social order of Brazilian agrobusiness. Sanitary quality of milk produced in Brazil still remains well below the technically recommended, compromising both the harmlessness of dairy products offered to population and Brazil’s possibilities to be established as a strong competitor in international market. Improvements in milk sanitary quality are linked with the adoption of Good Agricultural Practices (GAP), aiming to correct possible flaws in the production process. The objective of the present study was to identify the characteristics of milk producing proprieties associated with a state’s Cooperative from Rio Grande do Sul (RS), as well as evaluate the efficacy of the implantation of the Safe Food Program (SFP Milk - Field) in the scope of conformity legal criteria in the hygienic-sanitary quality of milk produced. For that, methodology of Oriented Implantation developed by the SFP Milk - Field was used, in 59 milk producers. At the start and ending of the implantation, data for the characterization of proprieties was identified, whereas indicators of the conformity percentage of items from the verification list of GAP were evaluated, the last being divided in localization and installations; water safety; health and capacity of workers; milking handling; hygiene of equipment and utensils; refrigeration and storage; plague control; sanitary handling and food storage, as well as hygienic-sanitary quality of raw material (milk), through the analyses of somatic cell count (SCC) and total bacterial count (TBC), before and during the program’s implantation For data tabulation, software “Statistical Package for the Social Sciences” (SPSS) was used together with ANOVA test, aiming to identify the statistical difference between results with significance of 5% for average analysis. All proprieties studied had mechanical milking and refrigeration equipment; average milk production was of 21.81 L/cow/day, in a herd of 3,127 cows, being 1,577 in lactation, totalizing a production of 36,130 Liters per day. General conformity results showed a positive evolution of 64.41%, reaching up to 96.20% at the end of implantation. SCC and TBC counting showed significant decreases with the development of the project. Based on the exposed, it is possible to conclude that the adoption of GAP through SFP is effective for the adequacy of milk producing proprieties to legal criteria, as well as to the improvement of milk hygienic and sanitary quality.
Araujo, Fernando Oliveira de. "Qualidade do leite produzido nos meses de inverno e verão na região central do Rio Grande do Sul em diferentes níveis tecnológicos". Universidade Federal de Santa Maria, 2011. http://repositorio.ufsm.br/handle/1/10771.
Pełny tekst źródłaWith the objective to evaluate the effect of the level of specialization of dairy production units, what it results in more intense use, or not, production resources, on the quantiqualitative aspects of milk, an evaluation was conducted in dairy production units (UPL) in two mesoregions of the state of Rio Grande do Sul: West Central Mesoregion Rio-Grandense East Central Mesoregion Rio-Grandense. Milk samples were collected in forty property and analyzed the composition and quality of milk. The UPL were divided into two groups: Specialized System (ES) and Semi-Specialized System (SS). The classification of production systems was based on the genetic composition of the herd, milking system, equipment used for cooling milk, nutritional planning of the herd, use of pastures and fodder reserves, presence of technical assistance in the property and the level of importance of the dairy activity for the farmers. Were also collected data regarding the productivity of properties, such as stocking rate and milk production per hectare. Milk components (fat, protein, lactose and solids) were determined by Near-infrared spectroscopy (NIRS) and the somatic cell count and total bacterial count were realized by eletronic count flow cytometry. There were no significant differences in composition, milk quality and productivity between the producers of the ES in winter and summer. In the SS system only percentage of fat was difference during winter and summer. For other values there was no difference in the SS. When compared, the SS and SE systems differ in composition, quality and productivity. Compared with the SS, the milk produced in the SE had lower chemical composition, but with better microbiological quality and higher production volume.
Com o objetivo de avaliar o efeito do nível de especialização de propriedades leiteiras, o que resulta em uso mais intenso, ou não, dos recursos de produção, sobre os aspectos quanti-qualitativos do leite, foi realizada uma avaliação de unidades produtoras de leite (UPL) de duas mesorregiões do estado do Rio Grande do Sul: Mesorregião Centro Ocidental Rio-Grandense e Mesorregião Centro Oriental Rio-Grandense. Foram coletadas amostras de leite de 40 UPLs e realizadas análises de composição química e qualidade microbiológica do leite. As UPLs foram divididas em dois grupos: Sistema Especializado (SE) e Sistema Semi-Especializado (SS). A classificação dos sistemas de produção foi baseada na composição genética do rebanho, equipamentos utilizados para refrigeração do leite, planejamento nutricional do rebanho, utilização de pastagens e reservas forrageiras, presença de assistência técnica na propriedade e grau de importância da atividade leiteira para os produtores. Também foram coletados dados referentes à produtividade das propriedades, como lotação animal e produção de leite por hectare. Os componentes do leite foram determinados pela espectrofotometria por radiação infravermelha e a contagem de células somáticas e contagem bacteriana total através de contagem eletrônica por citometria de fluxo. Não foram encontradas diferenças para composição química e qualidade microbiológica do leite e produtividade no SE nos meses de inverno e verão. Já no sistema SS apenas o teor de gordura apresentou diferença nos meses de inverno e verão. Comparado com o SS, o leite produzido no SE apresentou composição química inferior, porém com melhor qualidade microbiológica e maior volume produzido.
Fraga, Denize da Rosa. "Manejo reprodutivo e sanitário na bacia leiteira da região central do Rio Grande do Sul". Universidade Federal de Santa Maria, 2010. http://repositorio.ufsm.br/handle/1/10081.
Pełny tekst źródłaThe growth of the dairy production occurred from studies conducted with practical application in the farm. The aim of these studies was to evaluate the relationship of production systems with reproductive efficiency and milk quality of dairy cows in the central region of the RS/Brazil. In the first study, data from 150 holstein cows were investigated to detect the occurrence of postpartum disease within the first 45 days of lactation. Also, the effect of different production system levels highly specialized (n=50), specialized (n=50) and not specialized (n=50) and the pregnancy rate after the first artificial insemination (AI) were analyzed. Thirty-five percent (53/150) of females were diagnosed with postpartum disorders and 65% (97/150) remained healthy. At day 60 after AI, 41% (61/150) of the cows were pregnant. The occurrence of postpartum diseases decreased conception rate in the cows with post partum (P=0.0011) and only 30% (16/53) were pregnant at 60d. The pregnancy rate from all health cows was 46% (45/97). The two diseases with the highest incidence level were uterine infection (49%) and mastitis (30%).The combined conception rate of healthy cows from all systems was higher than those with postpartum disease (46.3% vs. 26.4%, P=0.0227). In all three systems, highly specialized, specialized, and not specialized, there was a correlation between sickness and the delay in conception (P=0.0018, P=0.0005 and P=0.0140), respectively. None of the production systems effectively reduced the occurrence of postpartum disease. These analyze of milk samples were collected from milk tanks (n=69) and from individual cows (n=3517) on highly specialized (HS, n=3), specialized (S, n=5) and not specialized (NS, n=7) production systems. Composition, somatic cell count (SCC) and urea nitrogen (UN) was analyzed in the different production systems, seasons and ranges allowed by the Federal Normative Instruction 51/2002 (IN51). Mean SCC of the tank samples was 604.900 cells mL-1. Only 42% (n=29/69) of the milk samples obtained from tanks reached the IN51 standard. Of these, 70% came from the HS (n=14/20), 39% from the S (n=9/23), 23% from NS (n=6/26) systems and 50% were obtained during fall (n =8/16). The mean individual milk sample SCC was 689.000 cells mL-1. Of these individual samples, 11% (n=375/3517) attended the IN51 standard. The same percentage (11%) of standard attendance was observed at each production system and 15% of these samples were obtained during the winter season (n=99/675). Fat, protein, total solids and SCC were similar between production systems. However, between individual samples there only was similarity on CCS. No difference was found on lactose, SCC and UN of tank samples between seasons. The average SCC on the S and HS production systems was less than on the NS one. SCC was above the IN51 limit during fall. There was an increase in UN (P<0.001) in the HS production system. In spring 48% of the individual samples and in summer 42% of the tank samples attended the UN standard. The individual analysis can be used to control and improve the milk quality.
O crescimento da bovinocultura de leite se deve as pesquisas realizadas com aplicação prática no campo. O objetivo deste estudo foi avaliar a relação dos sistemas de produção com a eficiência reprodutiva e a qualidade do leite dos rebanhos na região central do RS/Brasil. No primeiro estudo, os dados de 150 matrizes da raça holandesa foram analisados para verificar se os sistemas de produção empregados nas propriedades facilitam a ocorrência de doenças no pós-parto (até 45º dia de lactação), assim como o efeito do sistema especializado (n=50), semi-especializado (n=50) e não-especializado (n=50) de produção sobre a taxa de prenhez após a primeira inseminação artificial (IA). Os resultados revelaram menor taxa de prenhez nos animais doentes pós-parto e a ocorrência de doença pós-parto diminuiu a taxa de concepção (P=0,0011). A incidência de infecção uterina pós-parto (49%) foi superior à incidência de animais com mastite (30%). Todas as enfermidades contribuíram para atraso na concepção quando comparadas vacas sadias e com doenças pós-parto (P<0,001). Desta forma, nenhum dos sistemas de produção demonstrou ser um eficiente modelo de prevenção de doenças pós-parto. Concomitantemente realizou-se um estudo para verificar a qualidade do leite produzido em propriedades com diferentes sistemas de produção, estações do ano e padrões da Instrução Normativa 51/2002(IN51) do Ministério da Agricultura, Pecuária e Abastecimento. Amostras de leite bovino de tanque (n=69) e individuais (n=3517) foram coletadas em propriedades classificadas por sistemas de produção: especializado (ES, n=3), semi-especializado (SE, n=5) e não-especializado (NE, n=7). Analisou-se a composição, contagem de células somáticas (CCS) e nitrogênio uréico (NU) do leite. Amostras de tanque padrão IN51 resultaram em 42% (n=29/69) no geral (média de CCS 604,9 mil células mL-1), 70% no ES (n=14/20), 39% no SE (n=9/23), 23% no sistema NE (n=6/26) e 50% no outono (n=8/16). No geral, 11% (n=375/3517) das amostras individuais (média de CCS 689,0 mil células mL-1), 15% no inverno (n=99/675) e 11% nos três sistemas de produção atenderam a IN51. Amostras de tanque apresentaram similaridade entre os sistemas nos parâmetros gordura, proteína, sólidos totais e CCS. Amostras individuais foram similares apenas na CCS. Lactose, CCS e NU nas amostras de tanque entre as estações do ano foram similares. A média de CCS no SE e ES foi inferior ao NE, no entanto no outono ultrapassou o limite da IN51. Houve aumento no NU (P<0,001) no ES. Na primavera, 48% das amostras individuais e no verão 42% dos tanques apresentaram NU entre 11-16 mg dL-1. As análises individuais podem ser utilizadas para controle e melhoria da qualidade do leite.
Freitas, Larissa Nazareth de. "Impacto da mentalidade do produtor e do engajamento dos funcionários sobre a qualidade do leite". Universidade de São Paulo, 2016. http://www.teses.usp.br/teses/disponiveis/11/11139/tde-28112016-101317/.
Pełny tekst źródłaMastitis is a major disease faced by dairy farmers worldwide. One of the indicators directly related to the prevalence of the disease in the herd is the bulk tank somatic cell count (BTSCC). Recent studies showed that one of the risk factors associated with mastitis is the human factor. That is, factors related to management practices, farm management and personal characteristics of the farmer, such as personality, attitude, beliefs, intentions, skills, knowledge and others are important, besides to employee\'s engagement. Therefore, to understand the influence of humans is fundamental to control and prevent the disease. The main goal of this study was i) to determine whether the motivations and barriers perceived by farmers can explain the variation in the BTSCC, ii) to evaluate the farmer mindset about the business future and, iii) if the needs of dairy farms employees are being met. Thus, a study was conducted at 75 dairy farms in southern Brazil. Data collection was conducted through interviews with farmers end employees using a survey based on open questions and Likert scale answers. All surveys were given by the same researcher. Fogg Behavioral Model (FBM) was used to study the farmer mindset and Maslow\'s Motivation Theory was used to study employee\'s engagement. In statistical analysis, structural equation models and descriptive analyzes were used. Through the results found is possible to conclude that variations in BTSCC can be explained by the motivations and barriers perceived by farmers and that the Fogg Behavioral Model (FBM) used in this study can be used to explain the influence of human behaviors towards mastitis control. In addition, it is possible to conclude that dairy farmers in the study area have no positive mindset regarding the company\'s future and are unmotivated with the dairy business. Regarding the employees, they are unmotivated and there is a barrier of communication between the farmer and the employee, because the farmer does not know what her or his employees most valorize. Finally, this study showed that consulting companies focused on improving the milk quality should also pay attention to the human factor through the study of farmer mindset and employee\'s engagement.
Fraga, Cecília Archer de Menezes Castro. "Medicina da produção leiteira : estudos de relação entre o desempenho reprodutivo e as mastites". Master's thesis, Universidade de Lisboa, Faculdade de Medicina Veterinária, 2018. http://hdl.handle.net/10400.5/15046.
Pełny tekst źródłaO impacto das mastites na eficiência reprodutiva dos bovinos leiteiros, tem sido estudado ao longo dos últimos anos, por diversos autores. O objetivo do presente estudo, foi analisar a possível associação causal entre a ocorrência de mastites subclínicas e a alteração do desempenho reprodutivo. Recorrendo a uma base de dados de contraste leiteiro, na qual existiam registos provenientes de 9 explorações nacionais, introduzidos entre 1996 e 2016, procedeu-se à análise da relação da contagem de células somáticas, com o intervalo parto-conceção. Os resultados obtidos demonstraram que, à medida que aumenta a contagem de células somáticas, aumenta o intervalo parto-conceção. Tais resultados foram estatisticamente significativos e mais pronunciados para os dados relativos à segunda lactação. Observou-se ainda que, para cada aumento do número de eventos, cuja contagem de células somáticas se encontra acima do limiar de distinção entre infetado e saudável, o intervalo parto-conceção aumenta 28,7 dias para a primeira lactação e 27,9 dias para a segunda. Tais resultados, sugerem a hipótese de haver uma relação da cronicidade da infeção, com a fertilidade. Assim, à semelhança do reportado por autores anteriores, os resultados obtidos apontam a existência de uma relação entre as mastites subclínicas e o desempenho reprodutivo dos bovinos leiteiros.
ABSTRACT - Dairy Production Medicine: studies of the relationship between reproductive performance and mastitis - The impact of mastitis on reproductive performance of dairy cattle has been studied throughout the last years, by several authors. The objective of this study was to evaluate the possible causal association between the occurrence of subclinical mastitis and altered reproductive performance. Through the analysis of a database, in which there was access to milk recording data from 9 national dairy farms, introduced from 1996 to 2016, the relationship between the somatic cell count and the calving-to-conception interval was analyzed. The obtained results showed that, as the somatic cell count increases, the calving-to-conception interval increases. These results were statistically significant and more pronounced on the second lactation. Furthermore, it was observed that, with increases in the number of mastitis episodes, in which somatic cell counts were above the considered threshold between infected and healthy, the calving-to-conception interval progressively increased 28,7 days for the first lactation and 27,9 days for the second. These results support the existence of a relationship between the chronicity of the episodes and fertility. As such, similarly to results presented by previous authors, this study supports the existence of a direct relationship between mastitis and the reproductive performance of dairy cattle.
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Sant’Anna, Aline Cristina [UNESP]. "Fatores causais do grau de limpeza de vacas leiteiras e suas relações com a contagem de células somáticas". Universidade Estadual Paulista (UNESP), 2009. http://hdl.handle.net/11449/96598.
Pełny tekst źródłaCoordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
Os objetivos com este estudo foram descrever como as condições de higiene de vacas leiteiras variam ao longo do tempo e de acordo com as estações do ano; avaliar se as vacas são consistentes para sua higiene corporal; estudar as possíveis relações entre o escore de limpeza e o comportamento das vacas, em particular aqueles relacionados ao uso do espaço e à termorregulação e por fim, avaliar se há relação entre o escore de limpeza e a contagem de células somáticas do leite (CCS). Para isso foram utilizados animais de duas propriedades particulares localizadas no estado de São Paulo. Durante nove meses foi realizada uma avaliação mensal da higiene de todas as vacas em lactação, perfazendo um total de 3554 observações para 545 animais. A higiene foi expressa por meio de um escore de limpeza de quatro pontos (muito limpa, limpa, suja e muito suja). Para avaliar a relação entre o escore de limpeza e o comportamento foram avaliadas categorias comportamentais de postura, posicionamento e atividades dos animais para, no mínimo, 46 vacas em lactação, durante três dias consecutivos nos meses de julho e agosto de 2007 (estação seca) e dezembro de 2007 e janeiro de 2008 (estação chuvosa). Para o estudo da relação entre a higiene e a contagem de células somáticas individual das vacas foi avaliado um total de 2218 dados de CCS para 404 vacas. Foi encontrada variação individual na higiene das vacas, sendo que na estação seca os animais apresentaram-se mais limpos que na estação chuvosa. Apesar da variação, aproximadamente metade das vacas é consistente para a sua higiene, permanecendo maior parte do tempo em uma mesma condição – limpa para a maioria. Foi encontrada associação entre a higiene das vacas e o seu comportamento. Para explicar essa associação as categorias comportamentais podem ser caracterizadas em: comportamentos que determinam a transferência...
The aims of this study were to describe the variation on dairy cow’s body hygiene conditions over time and according to the seasons, verify if the cows are consistent for hygiene, to identify the relationship between the cleanliness score and the cow’s behavior, particularly those related to land use and thermoregulation and finally, to associate the cow’s cleanliness score and their milk somatic cell count (SCC). During nine months the body hygiene was accessed for lactating cows from two Brazilians commercial farms, a total of 3554 observations for 545 animals. The hygiene was expressed as a four points cleanliness score. To evaluate the relationship between the cleanliness score and behavior, behavioral categories of posture, positioning and activities were assessed for at least 46 dairy cows in two months of dry season and two of rainy season. The SCC was accessed for 404 cows, a total of 2218 data. Individual variation was found in the cow’s hygiene, and in the dry season the animals maintained cleaner than in the rainy season. Although the variation, approximately half of the cows are consistent for their hygiene - clean for the majority. The body hygiene was associated with the cow’s behavior. To explain this association the behavioral categories can be summarized as: behaviors that determine the directly transfer of dirt to the cows’ body (to lie down in a mud surface), while others behaviors are indirectly related to the transfer of dirty (lie down in a shaded place). In addition the behaviors as rumination and feeding does not determine the direct transfer of dirt to the body, however, these may be indicators of heat tolerance and the individual social ranking in the group, and differences in these characteristics are related to exposure of animals to certain dirty areas. The cleanliness score have effect on SCC (F = 4.85; df = 3; p < 0,01), and good hygiene condition... (Complete abstract click electronic access below)
Dambrós, Dayane. "Prevalência de Corynebacterium sp. no leite de vacas, sua correlação com o manejo de ordenha e contagem de células somáticas". Universidade do Estado de Santa Catarina, 2012. http://tede.udesc.br/handle/handle/852.
Pełny tekst źródłaThe bovine mastitis is a disease that causes more losses in dairy farming, significantly reducing the production and milk quality. A causative agent of mastitis is the Corynebacterium sp. , especially the specie Corynebacterium bovis, but their role in intramammary infection is not yet defined, since some studies consider this agent, a minor pathogen of the mammary gland, causing no change in production and composition milk, though others, realize the large capacity of Corynebacterium sp. in causing mastitis, placing it as a risk factor for the development of the activity. Meet the microbiological profile of milk samples, the specific action of the agents in the mammary gland and its effect on milk quality, are of great importance in mastitis control programs. This study aimed to determine the prevalence of Corynebacterium sp. n the milk of cows from dairy herds located in five Brazilian states and to correlate the presence of this agent with the management of the milking herd and the somatic cell count of bulk tank milk and milk of individual cows. We conducted a longitudinal study from January 2010 to July 2011, in dairy herds located in the states of SC, PR, RS, MG and PE, which were performed in four colletions (at six months intervals) of milk samples in each herd. A questionnaire was applied in each farm to obtain data and information on the practices of milking herds, such as teat disinfection and teat drying, which may influence the occurrence of mastitis by Corynebacterium sp. Of the 4949 milk samples analyzed, submitted to microbiological culture, 666 (13,46%) had isolation of Corynebacterium sp. Minas Gerais was the state with the highest pravelence off this agent (21,07%) compared to others states. Risk factors associated with the management of milking, such as teat disinfection before and after milking and dry cow treatment showed no statistically significant influence on the prevalence of Corynebacterium sp. in milk samples analyzed. The isolation of Corynebacterium sp. in milk samples did not affect the SCC of bulk tank milk of the herds, but in the CMT, the presence of this agent caused variations in the number of positive mammary quarters and the degree of score in their test. Therefore Corynebacterium sp. is a causative agent of mastitis of great relevance not only by the frequency of isolation observed in this study, but also by the effect of CMT in individual cows and consequently in the herd SCC
A mastite bovina é a enfermidade que mais causa prejuízos na pecuária leiteira, reduzindo, significativamente, a produção e qualidade do leite. Um dos agentes causadores da mastite é o Corynebacterium sp., principalmente a espécie Corynebacterium bovis, porém seu papel na infecção intramamária ainda não é definido, pois alguns estudos consideram este agente, um patógeno menor da glândula mamária, sem causar alteração da produção e composição do leite, entretanto outros, constatam a grande capacidade do Corynebacterium sp. em causar mastite, colocando-o como um fator restritivo para o desenvolvimento da atividade leiteira. Conhecer o perfil microbiológico de amostras de leite, a ação específica dos agentes na glândula mamária e seu efeito na qualidade do leite, são de grande relevância em programas de controle da mastite. Este estudo teve como objetivos determinar a prevalência de Corynebacterium sp. no leite de vacas de rebanhos leiteiros localizados em cinco estados brasileiros e, correlacionar a presença deste agente com o manejo de ordenha dos rebanhos e com a contagem de células somáticas do leite do tanque e do leite individual das vacas. Foi realizado um estudo longitudinal, de janeiro de 2010 a julho de 2011, em rebanhos leiteiros localizados nos estados de SC, PR, RS, MG e PE, nos quais foram realizadas quatro coletas (semestrais) de amostras de leite em cada rebanho. Foi aplicado um questionário, em cada propriedade, para obter dados e informações sobre o manejo de ordenha dos rebanhos, como a desinfecção pré e pós-ordenha, secagem dos tetos, que possam influenciar na ocorrência de mastite por Corynebacterium sp. Do total de 4949 amostras de leite analisadas, submetidas a cultura microbiológica, 666 (13,46%) apresentaram isolamento de Corynebacterium sp. Minas Gerais foi o estado que apresentou a maior prevalência deste agente (21,07%) comparado aos demais estados. Os fatores de risco associados ao manejo de ordenha das propriedades, como a desinfecção dos tetos pré e pós-ordenha e o tratamento de vaca seca não apresentaram influência estatística significativa na prevalência de Corynebacterium sp. nas amostras de leite analisadas. O isolamento de Corynebacterium sp nas amostras de leite não afetou a CCS do leite do tanque dos rebanhos, porém no CMT, a presença deste agente causou variações no número de quartos positivos e no grau de escore no respectivo teste. Portanto, Corynebacterium sp. é um agente causador de mastite de grande relevância, não só pela freqüência de isolamento observada no presente estudo, mas também pelo efeito no CMT individual das vacas e consequentemente na CCS do rebanho
Cardozo, Leonardo Leite. "Identificação de fatores de risco para mastite subclínica em rebanhos do estado de Santa Catarina". Universidade do Estado de Santa Catarina, 2013. http://tede.udesc.br/handle/handle/888.
Pełny tekst źródłaThis study was aimed to identify risk factors of subclinical mastites in dairy herds located in the region of West, Midwest, Serrana and Southern in Santa Catarina State, Brazil. The experiment was conducted in 30 dairy herds, totaling approximately 1.700 lactating cows, participating in Dairy Control Service of Santa Catarina Association of Cattle Breeders (ACCB) during the period November 2011 to December 2012. Information on the characterization of milk-producing units and their management programs were obtained by survey with the farmes as well as by monitoring the farms. During the development of the work selected farms were visited three times to update the data, and after the visits has assembled a database with information from test dairy controls and survey. The dynamics of subclinical mastitis was determined from the ratio of the somatic cell count (SCC) of the previous month to the current month s SCC. In the analysis of the dynamic of intramammary infections was initially used the Chi-square (X²) to test associations between each independent variable with the dyna =mics of mastitis, followed by logistic regression analysis to estimate the risk of new infections in contrast to healthy cows and chronic infections compared to new infections. The average count of SCC was 493, 728 cells/mL, being that in 32.3% of control cows were healthy (SCC<200,000/mL). the explanatory variables that composed the final logistic regression model for risk of a cow developing a new case of mastitis in relation to healthy cows were parity, hyperkeratosis at the teat, udder depth, udder dirt and adoption of milking line. Cows with> 4 birth had 1.65 times the risk of new intramammary infection compared to ptimiparous cows (P <0.01). For cows with a mean score of hyperkeratosis ends above of 3 (scale of 1 to 4) was observed 1.61 times greater risk of developing new infections, cows with udders below the hock achieved risk of 2.46 (P <0.001) and cows with dirty udders many showed risk of 1.55 times of becoming infected. Farms hat do not perform line for milking animals had infected increased the 1.55 times greater risk of developing infections. The final model of logistic regression showed the best explanation for the risk of developing a chronic infection of subclinical mastitis in relation to new subclinical mastitis including maintenance of milking equipment, stage of lactation and udder depth. Farmsn that perform maintenance of milking equipment only eventual had 2.17 times greater risk of owning cows with chronic infection (P <0.001) cows above 100 days in milk already increased risk, ranging from from 2.70 to 5.88 and cows with udder depth at or below the hock shown risk approximately 1.65 compared to the cows shallowe udders (P <0.01)
O presente trabalho teve como objetivo identificar os fatores de risco para mastite subclínica em propriedades leiteiras localizadas nas mesorregiões Oeste, Meio-oeste, Serrana e Sul do Estado de Santa Catarina. O experimento foi desenvolvido em 30 rebanhos, perfazendo aproximadamente 1.700 vacas em lactação, participantes do Serviço de Controle Leiteiro da Associação Catarinense de Criadores de Bovinos (ACCB) durante o período de novembro de 2011 a dezembro de 2012. Informações sobre a caracterização das unidades produtoras de leite e seus programas de manejo foram obtidas a partir de questionário aplicado aos produtores, bem como através do acompanhamento das propriedades. Durante o desenvolvimento do trabalho as propriedades selecionadas foram visitadas três vezes para atualização dos dados, sendo após as visitas foi montada uma base de dados com informações do controle leiteiro e do questionário. A dinâmica da mastite subclínica foi determinada da relação da contagem de células somáticas (CCS) do mês anterior com a CCS do mês atual. Para análise da dinâmica das infecções intramamárias foi primeiramente utilizado o teste Qui-quadrado (2) para testar associações entre cada variável independente, seguida de análise de regressão logística para a estimativa de risco de novas infecções em contraste às vacas sadias e infecções crônicas em comparação às novas infecções. A contagem média da CCS foi de 493.728 células/mL, sendo que em 43,3% dos controles as vacas encontravam-se sadias (CCS <200.000/mL). As variáveis explicativas que compuseram o modelo final de regressão logística para risco de uma vaca desenvolver um novo caso de mastite em relação às vacas sadias foram à ordem de parto, hiperqueratose da 8 extremidade dos tetos, profundidade do úbere, sujidade do úbere e adoção de linha de ordenha. Vacas com > 4 partos apresentaram risco de 1,65 vezes de nova infecção intramamária em relação às vacas primíparas (P <0,01). Para vacas com escore médio de hiperqueratose acima de 3 (escala de 1 a 4) foi observado risco 1,61 vezes maior de contrair novas infecções, vacas com úberes abaixo da linha do jarrete obtiveram risco de 2,46 (P <0,001) e vacas com úberes muitos sujos apresentaram taxa de risco de 1,55 vezes maior de tornar-se infectadas. Propriedades que não realizam linha de ordenha para animais mais infectado apresentaram taxa de risco de 1,55 vezes mais de contraírem infecção. O modelo final de regressão logística que apresentou melhor explicação para o risco de desenvolver uma infecção de mastite subclínica crônica em relação a novos casos de mastite subclínica incluiu as características manutenção dos equipamentos de ordenha, estágio de lactação e profundidade do úbere. Propriedades que realizam a manutenção dos equipamentos de ordenha de forma apenas eventual apresentaram taxa de risco 2,17 vezes maior de possuir vacas com infecção crônica (P <0,001), vacas a partir de 100 dias de lactação já apresentam um risco aumentado, variando de 2,70 a 5,88 e vacas com profundidade do úbere junto ou abaixo da linha do jarrete mostraram risco de aproximadamente 1,65 em comparação com as vacas com úbere mais raso (P <0,01)
ROSA, Poliana P. S. G. "Qualidade do leite de vacas em torneios leiteiros". Universidade José do Rosário Vellano, 2015. http://tede2.unifenas.br:8080/jspui/handle/jspui/160.
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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES
The objective of this research was to evaluate the physicochemical characteristics of the Dutch and crossbred cows milk originating from dairy tournaments, in the southern region of Minas Gerais, in the period from March to October 2012, using the nonparametric data for protein, fat, lactose, total solids, nonfat dry extract and somatic cell count variables. Normative Instruction 62 establishes maximum levels of somatic cell count of 500,000 cells / ml of milk, minimum fat content of 3.0%, total solids 11.4%, 2.9% protein, dry extract 8.4%. The somatic cell count reflects the health of the mammary gland of the animal. Of the 108 samples of milk collected from cows participants on the last day of the milk match, after complete milking and weighing of milk, 24% of the animals showed somatic cell counts that do not fit the parameters established by the Normative Instruction 62. The other parameters evaluated as lactose, fat, total solids and nonfat dry extract showed significant differences by comparing the milk with high somatic cell count, milk with low somatic cell count. The level of milk protein with high somatic cell count remained in the Normative Instruction 62 standard, because of the increase of plasma proteins in milk as a result of the inflammatory response. Most milk samples from dairy tournaments did not fit in Instruction 62, as the increase in somatic cells interfered in the chemical physical quality.
Objetivou-se nesta pesquisa avaliar as características físico-químicas do leite de vacas holandesas e mestiças oriundas de torneios leiteiros na região do Sul de Minas Gerais, no período de março a outubro de 2012, sendo utilizados os dados não paramétricos para as variáveis de proteína, gordura, lactose, sólidos totais, extrato seco desengordurado e contagem de células somáticas. A Instrução Normativa 62 estabelece níveis máximo de contagem de células somáticas de 500.000 células/mL de leite, teores mínimos de gordura de 3,0%, sólidos totais de 11,4%, proteína 2,9%, extrato seco desengordurado 8,4%. A contagem de células somáticas reflete na saúde da glândula mamária do animal. Das108 amostras de leite coletadas das vacas participantes no último dia do torneio leiteiro, após a ordenha completa e pesagem do leite, 24% dos animais apresentaram contagem de células somáticas que não se enquadram nos parâmetros estabelecidos pela Instrução Normativa 62. Os demais parâmetros avaliados como lactose, gordura, sólidos totais e extrato seco desengordurado não apresentaram diferenças significativas, comparando o leite com contagem de células somáticas altas, com leite com contagem de células somáticas baixas. O nível de proteína em leite com contagem de células somáticas altas se mantiveram no padrão da Instrução Normativa 62, pois houve um aumento das proteínas plasmáticas no leite em decorrência da resposta inflamatória. Conclui-se que a maioria das amostras de leite coletadas em torneios leiteiro não se enquadraram na Instrução Normativa 62.
GUIMARÃES, Caroline Paixão do Amaral. "Impacto da assistência técnica sobre a qualidade do leite". Universidade Federal de Goiás, 2008. http://repositorio.bc.ufg.br/tede/handle/tde/925.
Pełny tekst źródłaIn a globalization context, producing food only focused on quantity makes no more sense. At the same time, the quality becomes the most important step on food processing chain, since it s essential to guarantee life quality. Then, we purposed this study to verify the effect of private technical assistance on milk quality. The study was carried out during the dry and rain periods of the year, on 40 dairy farms located at the counties of Bela Vista de Goiás, São Miguel do Passa Quatro, Piracanjuba and Cristianópolis, in Goiás State, Brazil. The farms were randomly selected from herds with high results of somatic cell count (SCC) and total bacterial count (TBC). The effect of technical assistance on milk quality was evaluated using the results of milk analyses before and after visits of technicians on the farms. Milk samples were taken from bulk milk tanks and analyzed to somatic cell count (SCC) and total bacterial count (TBC) in electronic devices. We observed a significant decrease on the SCC and TBC after farmers had received technical assistance on milking procedures and mastitis control. The rain period didn t affect the observed results. As the SCC decreased, we observed an increase on SNF values of milk. So, we confirmed that technical assistance leaves to better milk quality, in any time of the year
No mundo globalizado, produzir alimentos com a visão única voltada para a quantidade não faz sentido. A qualidade torna-se a etapa mais importante do processo industrial, pois constitui garantia da qualidade de vida. Objetivou-se com o presente estudo verificar o efeito da assistência técnica privada na qualidade do leite. Foram acompanhadas 40 propriedades rurais localizadas nos municípios goianos de Bela Vista de Goiás, São Miguel do Passa Quatro, Piracanjuba e Cristianópolis, no período de secas e águas. Os produtores foram previamente selecionados por sorteio dentre aqueles que apresentavam elevadas contagens de células somáticas (CCS) e bacteriana total (CBT) no leite. O efeito da assistência técnica foi avaliado por meio de análises realizadas no leite antes e após os produtores receberem as visitas dos técnicos. Amostras de leite foram colhidas em tanques de refrigeração por expansão direta e submetidas às análises de CBT e CCS, em equipamentos eletrônicos. Observou-se que os valores de CBT e CCS diminuíram significativamente após os produtores receberem assistência técnica. A intensidade das chuvas não interferiu nos resultados de CCS e CBT. Concomitantemente à redução dos valores de CCS, houve aumento nos valores do extrato seco desengordurado do leite. Verificou-se que a assistência técnica privada proporcionou melhoria da qualidade do leite, independentemente da época do ano
Alessio, Dileta Regina Moro. "Estudo meta-analítico e análise de banco de dados do teor de lactose no leite bovino". Universidade do Estado de Santa Catarina, 2013. http://tede.udesc.br/handle/handle/890.
Pełny tekst źródłaCoordenação de Aperfeiçoamento de Pessoal de Nível Superior
Lactose content in milk require extensive studies, mainly in Brazilian conditions, in wich herds are still situations of nutritional imbalance, problems of energy deficiency and underfeeding, as wel as intramammary infections. The objective was to evaluate the factors influencing the variation of lactose in test day cow s milk and bulk tank milk data, through the use of multivariate analysis. The data control of 37 herds in the state of Santa Catarina were provides by Santa Catarina Association of Cattle Breeder (ACCB), totaling 46242 monthly controls of Holtein (58.5%) and Jersey (41.5%) from 2009 to 2012. Data grom monthly samples of milk tanks in the period 2009-2011 were provide by the Milk Quality Laboratory of the University of Contestado / CIDASC totaling 427138 samples. It was conducted a survey on the national scientific articles of public domain, that relates the dairy cows diet and milk composition, published between 2000 and 2012. The search of the sciencitif articles was performed on the Scientific Eletronic Library Online (SciELO), Brazilian Institute of Information in Science and Technology (IBICT), in Journal Portal of CAPES and directly in the mayor journals of Agrocultural Sciences. The scientific articles were selected over the resume that needed to have to be tabulated: the lactose s content, milk composition, chemical analysis of diet and animal performance, being 36 articles contain 141 treatments. The records were evaluated by multi variate analysis using multiple correspondence analysis, factorial and cluster analysis. The database showing that ILow lactose was related to high somatic cell counts (SCS), evaluated breeds, as well as the milk yield and fat protein content were not associated with the lactose. Cluster analysis revealed one group of data both breeds, with low lactose, and high SCS, stage of lactation and parity, with contrasting groups with values characteristic from Holstein and Jersey breeds, respectively. As in the database analysis, meta-analysis has also demonstrated that the lactose content is not related to total content of fat and protein in milk, there are, however, small relation with milk production. The lactose content were related to food intake, as well as the levels of total digestible nutrients, non-fibrous carbohydrate, crude protein in the diet, having no relation with the content of neutral detergent fiber in diet. It is concluded that low levels of lactose are related to the high SCS, advanced stage of lactation and higher number of lactations. Nutritional factors affecting more pronounced lactose content are the dry matter intake, the energy value of the diet (TDN content) and the content of non-fiber carbohydrates and crude protein
Os teores de lactose no leite necessitam de estudos aprofundados, principalmente em condições brasileiras, nas quais os rebanhos ainda vivem situações de desequilíbrio nutricional, por problemas de deficiência energética e subnutrição, bem como problemas de sanidade da glândula mamária. Assim, objetivou-se avaliar os fatores que influenciam a variação de lactose do leite bovino em rebanhos sobre controle leiteiro e dados de tanque de expansão e determinar os fatores nutricionais que interferem no teor de lactose do leite produzido em condições brasileiras por meio da meta-análise de dados da literatura nacional, empregando análise multivariada. Os dados de controle leiteiro de 73 rebanhos do estado de Santa Catarina foram disponibilizados pela Associação Catarinense de Criadores de Bovinos (ACCB), totalizando 46242 controles mensais de vacas das raças Holandês (58,5%) e Jersey (41,5%) no período de 2009 a 2012. Dados de amostras mensais de tanques de resfriamento de leite no período de 2009 a 2011 foram disponibilizados pelo Laboratório de Qualidade de Leite da Universidade do Contestado/CIDASC, totalizando 427138 amostras. Foi realizado um levantamento dos trabalhos científicos nacionais de domínio público envolvendo a alimentação de vacas leiteiras e a composição do leite, publicados no período 2000 a 2012. Após seleção dos trabalhos, a base ficou composta por 36 trabalhos com 141 tratamentos. Os dados foram avaliados através de análise multivariada, utilizando análise de correspondência múltipla, fatorial e de agrupamento. As análises dos bancos de dados revelaram que baixos teores de lactose apresentaram relação com elevada contagem de células somáticas, em vacas com estágio de lactação avançado e elevada ordem de parto. As raças avaliadas, bem como a 8 produção e concentrações de gordura e proteína no leite não apresentaram relação com o teor de lactose. A análise de agrupamento revelou um grupo formado por dados de controles leiteiros de ambas as raças, com baixo teor de lactose, escore de células somáticas (ECS), estágio de lactação e número de partos mais elevados, contrastando com dois grupos com valores médios característicos das raças Holandês e Jersey, respectivamente. Assim como nas análises de banco de dados, a meta-análise também demonstrou que o teor de lactose não apresenta relação com os teores de gordura e proteína do leite, havendo, entretanto, menor relação com a produção de leite. O teor de lactose apresentou relação com o consumo de matéria seca, com os teores de nutrientes digestíveis totais (NDT), carboidratos não fibrosos (CNF) e teor de proteína da dieta, assim como relação negativa com o teor de fibra em detergente neutro da dieta. Conclui-se que baixos teores de lactose estão relacionados à elevada contagem de células somáticas, estágio de lactação avançado e vacas com maior número de lactações. Os fatores nutricionais que afetam mais pronunciadamente o teor de lactose são o consumo de matéria seca, o valor energético da dieta (teor de NDT) e os teores de carboidratos não fibrosos e proteína bruta
Vargas, Diego Prado de. "EFEITO DA CONTAGEM DE CÉLULAS SOMÁTICAS E CONTAGEM BACTERIANA TOTAL SOBRE OS CONSTITUINTES DO LEITE". Universidade Federal de Santa Maria, 2012. http://repositorio.ufsm.br/handle/1/5728.
Pełny tekst źródłaThe study aims to evaluate the effect of somatic cell count (SCC) and total bacterial count (TBC) on the constituents of milk, checking the influence that the climatic variables have on these hygienic-sanitary indicators. Data were obtained from 1,541 dairy farms located in 15 municipalities in the dairy region of Vale do Taquari, Rio Grande do Sul. It was tabulated the data from somatic cell count (SCC), total bacterial count (TBC) and milk composition, from June 2008 to December 2011, totaling 44,089 samples. The ambient temperature showed positive and significant correlation to score of somatic cell, while rainfall and relative humidity air showed no correlation. Moreover, the climatic variables have no significant correlation to the TBC. The fat, protein, minerals and total solids were directly correlated with the SCC and TBC, while solids-not-fat and lactose showed an opposite behavior. The principal component analysis (PCA) followed by agglomerative hierarchical clustering method, have showed that milk from SCC 401,000 to 750,000 cell mL-1 and TBC from 100,000 to 1,000,000 CFU mL-1, have the same quality, not justifying stratification in these intervals. In addition, it was observed that only limits regulatory standards are not sufficient to improve the quality of milk, suggesting parameters for payment system based on the bonus and penalty relative to the TBC and SCC milk.
Este estudo teve por objetivos avaliar o efeito da contagem de células somáticas (CCS) e da contagem bacteriana total (CBT) sobre os constituintes do leite, verificando a influência que as variáveis climáticas exercem sobre estes indicadores higiênico-sanitários. Os dados utilizados foram de 1.541 unidades produtoras de leite referentes a 15 municípios da bacia leiteira do Vale do Taquari, Rio Grande do Sul. Foram tabulados os dados de contagem de células somáticas (CCS), contagem bacteriana total (CBT) e composição centesimal do leite, referentes ao período de junho de 2008 a dezembro de 2011, totalizando 44.089 amostras analisadas. A temperatura ambiente apresentou correlação positiva e significativa com o escore de células somáticas, enquanto a precipitação pluviométrica e umidade relativa do ar ausência de correlação. Por outro lado, as variáveis climáticas não apresentaram correlação significativa com a CBT. Os teores de gordura, proteína, minerais e sólidos totais foram diretamente correlacionados com a CCS e a CBT, enquanto que os sólidos não gordurosos e a lactose apresentaram comportamento inverso. A análise de componentes principais (ACP) seguida pelo método hierárquico aglomerativo de agrupamento, permitiu constatar que leites com CCS maiores que 400.000 até 750.000 céls mL-1 e CBT superiores a 100.000 até 1.000.000 UFC mL-1, apresentam a mesma qualidade, não justificando a estratificação de intervalos nesta amplitude de variação. Paralelamente, observou-se que somente limites de normas regulatórias não são suficientes para melhoraria da qualidade do leite, sugerindo-se, parâmetros para sistemas de pagamento baseado na bonificação e penalização em relação à CCS e CBT do leite.
Felleki, Majbritt. "Genetic Heteroscedasticity for Domestic Animal Traits". Doctoral thesis, Högskolan Dalarna, Statistik, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:du-14310.
Pełny tekst źródłaAlmeida, Thamara Venâncio de. "Efeito da temperatura e do tempo de armazenamento de amostras de leite cru nos resultados das análises eletrônicas". Universidade Federal de Goiás, 2015. http://repositorio.bc.ufg.br/tede/handle/tede/5088.
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For assessing compliance with the quality requirements established by the Normative Instruction No. 62, a milk sample each property or community tank should be analyzed on a monthly basis by one of the laboratories accredited by the Brazilian Laboratories Network for Milk Quality Control . There are still doubts about what would be the maximum temperature and the time of milk sample storage without jeopardizing the results of the electronic analysis. The objective of this study was to evaluate the effects of temperature and storage time of cooled samples of raw milk on the results of milk quality electronic analysis. Refrigerated raw milk samples were collected from expansion tanks for individual use of farms located in the middle region of the state of Goiás, and stored at four different temperatures (3 °C, 11 °C, 17 °C and 25 °C) for 16 days. Total bacterial count (TBC), somatic cell count (SCC) and chemical composition were performed daily. The results were submitted to analysis of variance in split plot design in randomized blocks, and the means were compared by Duncan test. We concluded that, when azidiol is added as preservative to samples for TBC, they can be analyzed up to 16 days after collection when stored at temperatures of 3 °C and 11 °C, and up to 10 days when stored at 17 °C. Moreover, when bronopol is added as preservative, samples for SCC and chemical composition analysis can be stored for up to 16 days after collection when stored at temperatures of 3 °C and 11 °C, and for up to seven days when stored at 17 °C.
Para a avaliação do cumprimento dos requisitos de qualidade estabelecidos pela Instrução Normativa nº 62, uma amostra de leite de cada propriedade ou tanque comunitário deve ser analisada mensalmente por um dos laboratórios credenciados pela Rede Brasileira de Laboratórios de Controle da Qualidade do Leite. Ainda existem dúvidas sobre quais seriam a temperatura e o tempo máximos de armazenamento das amostras de leite sem que houvesse comprometimento dos resultados das análises eletrônicas. Objetivou-se com este trabalho avaliar os efeitos da temperatura e do tempo de armazenamento de amostras de leite cru refrigerado nos resultados das análises eletrônicas da qualidade do leite. Amostras de leite cru refrigerado foram coletadas de tanques de expansão de uso individual de fazendas localizadas na mesorregião Centro Goiano no Estado de Goiás e armazenadas em quatro temperaturas diferentes (3°C, 11°C, 17°C e 25°C) durante 16 dias. Foram realizadas diariamente análises de contagem bacteriana total (CBT), contagem de células somáticas (CCS) e composição química. Os resultados obtidos foram submetidos à análise de variância em esquema de parcelas subdivididas no tempo em delineamento de blocos ao acaso e as médias comparadas pelo teste de Duncan. Concluiu-se que as amostras destinadas à análise de CBT, adicionadas do conservante azidiol, podem ser analisadas por até 16 dias após a coleta quando armazenadas em temperaturas de 3°C e 11°C e por até 10 dias quando armazenadas a 17°C. E as amostras destinadas às análises de CCS e composição química, adicionadas do conservante bronopol, podem ser analisadas por até 16 dias após a coleta quando armazenadas em temperaturas de 3°C e 11°C e por até sete dias quando armazenadas a 17°C.
Busanello, Marcos. "Indicadores epidemiológicos de mastite subclínica, previsão da contagem de células somáticas do tanque e seu impacto relacionado ao pagamento por qualidade do leite em rebanhos leiteiros brasileiros". Universidade de São Paulo, 2017. http://www.teses.usp.br/teses/disponiveis/11/11139/tde-08062017-101341/.
Pełny tekst źródłaSubclinical mastitis (SM) is the most prevalent disease in dairy herds and can be identified by individual somatic cell counts (SCC) of cows. From this, indicators can be calculated as, for example, prevalence and incidence. Prevalence refers to the number of infected cows in a herd at a given time, while the incidence estimates the rate of new intramammary infections over time. High prevalence and incidence values result in high bulk tank SCC (BTSCC), which consequently leads to penalties from payment programs based on milk quality (PPBMQ). In this way, estimating current values of prevalence and incidence of SM related to future values of BTSCC and financial losses from PPBMQs becomes important to stimulate the improvement of the quality of milk produced in Brazil. Therefore, the objective of this study is to estimate the epidemiological indicators of SM in Brazilian dairy herds, besides to predicting the BTSCC and relating it to the financial losses due to the PPBMQ. For this, two databases were used, the first one with individual SCC data from cows to estimate the prevalence and incidence of SM, and the second with BTSCC data for prediction and calculation of financial losses due to PPBMQ. For statistical analysis, the mixed generalized linear model was used to compare the prevalence and incidence of SM between years, regions, herd size and number of test-day categories sent during the studied period, as well as time series models for prediction of BTSCC and multiple linear regressions to predict the probability of changing the current payment class for milk quality. The results indicate that both prevalence and incidence of SM remained high and with a slight tendency to increase over the years studied, and there were no differences between regions and herd sizes. On the other hand, herds that performed more test-day during the studied period presented a lower prevalence, showing the importance of the routine analysis of individual SCC. For BTSCC, values have remained high in recent years and no trend for improvement. The probability of class change was strongly affected by the mean and standard deviation of BTSCC for classes 1 and 2 (1,000 to 200,000 and 201,000 to 400,000 cells/mL, respectively). Time series models indicated that at some point of the year, farms could not remain in their current class and accumulated financial losses due to PPBMQ. Finally, this study allows to conclude that the prevalence and incidence of SM are high and do not improve over the years, and this ends up increasing the BTSCC values. In addition, there are financial losses in all classes of PPBMQ, showing that producers have not been efficient in capturing the maximum PPBMQs bonus. Therefore, the development of milk quality programs should be a priority in order to improve the quality of milk from Brazilian herds.