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Artykuły w czasopismach na temat "Ruminants"
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Mlambo, Victor, i Caven M. Mnisi. "Optimizing ruminant production systems for sustainable intensification, human health, food security and environmental stewardship". Outlook on Agriculture 48, nr 2 (31.03.2019): 85–93. http://dx.doi.org/10.1177/0030727019840758.
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Whereas the contribution of ruminants to human civilization remains unequivocal, there are concerns regarding the unintended negative consequences of rearing these animals for food. These concerns range from the ruminant’s contribution to greenhouse gas emissions to negative impacts of its products on the health of consumers. Rearing ruminants for food is thus seen as the root cause of ills such as climate change, species extinction, deforestation, food insecurity, cardiovascular disease, obesity, cancer and diabetes. Indeed, critics of ruminant production envision a future where humanity does not have to rely on animal products for food. They are convinced that this would be the panacea to food and nutrition insecurity, environmental pollution and meat-induced nutritional disorders and diseases in humans. The critics seem to be unaware of the wide diversity of ruminant production systems in use as well as the array of benefits that can be derived from these enterprises. For instance, there are large human communities that inhabit climatically hostile areas, which have no food crop production potential. Food and nutrition needs of these communities are largely dependent on nourishment provided by products and income derived from ruminants and other herbivores. The aim of this review article is to interrogate the validity of the concerns around the use of ruminants for food and highlight appropriate strategies and technologies that may be applied to mitigate some of these challenges. We conclude that solutions already exist that have the potential to deliver efficient, environmentally friendly and consumer-conscious ruminant production systems based on high standards of animal welfare. Such sustainable production systems will ensure that ruminants continue to play a crucial role in food and nutrition security of humans as they have done for millennia.
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Gibbons, P. M., i M. E. Pesato. "Development of competencies for new graduates in small ruminant practice by utilizing a survey of current practitioners". American Association of Bovine Practitioners Conference Proceedings, nr 55 (17.07.2023): 234. http://dx.doi.org/10.21423/aabppro20228707.
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There are no standardized clinical competencies for new graduates interested in small ruminant herd health, medicine and surgery. This void is obvious as other professional veterinary associations publish competency guidelines for new graduates. Small ruminants are becoming increasingly popular with the development of niche markets, low startup cost and increased interest in livestock production for home consumption by owners in suburban areas, which leads to more mixed and small animal practitioners being tasked with seeing small ruminants. A survey was sent to small ruminant practitioners in North America to gauge the type of small ruminants seen by the practice, procedures performed on small ruminants, and small ruminant disease prevalence in the practice. Results from this survey will be used to establish clinical competencies for new graduates interested in small ruminant practice.
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Chen, Lei, Qiang Qiu, Yu Jiang, Kun Wang, Zeshan Lin, Zhipeng Li, Faysal Bibi i in. "Large-scale ruminant genome sequencing provides insights into their evolution and distinct traits". Science 364, nr 6446 (20.06.2019): eaav6202. http://dx.doi.org/10.1126/science.aav6202.
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The ruminants are one of the most successful mammalian lineages, exhibiting morphological and habitat diversity and containing several key livestock species. To better understand their evolution, we generated and analyzed de novo assembled genomes of 44 ruminant species, representing all six Ruminantia families. We used these genomes to create a time-calibrated phylogeny to resolve topological controversies, overcoming the challenges of incomplete lineage sorting. Population dynamic analyses show that population declines commenced between 100,000 and 50,000 years ago, which is concomitant with expansion in human populations. We also reveal genes and regulatory elements that possibly contribute to the evolution of the digestive system, cranial appendages, immune system, metabolism, body size, cursorial locomotion, and dentition of the ruminants.
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Flint, AP. "Interferon, the oxytocin receptor and the maternal recognition of pregnancy in ruminants and non-ruminants: a comparative approach". Reproduction, Fertility and Development 7, nr 3 (1995): 313. http://dx.doi.org/10.1071/rd9950313.
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Ruminant and non-ruminant members of the Artiodactyla appear to use different mechanisms for the maternal recognition of pregnancy. In ruminants, the trophoblast of the developing blastocyst produces a characteristic Type I interferon of the interferon-tau family; this acts by blocking endometrial synthesis of the oxytocin receptor. A similar mechanism applies to domestic ruminants (sheep, cow, goat) and deer. In roe deer, which have embryonic diapause and are monoestrus, there is no requirement for a pre-implantation blastocyst signal to ensure maternal recognition of pregnancy. This paper compares the mechanisms leading to the maternal recognition of pregnancy in ruminants with that suggested to occur in a non-ruminant (the domestic pig).
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Zammit, V. A. "Ketogenesis in the liver of ruminants – adaptations to a challenge". Journal of Agricultural Science 115, nr 2 (październik 1990): 155–62. http://dx.doi.org/10.1017/s0021859600075080.
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The descriptive aspects of hepatic fatty acid metabolism, and of ketogenesis in particular, have been extensively described for ruminants. There is, however, a distinct lack of information on the more mechanistic aspects of the subject. The biochemical profile of the livers of ruminant species shows both similarities to, and striking differences from, that of simple-stomached animals. Consequently, it may not always be valid to extrapolate from the situation in, say, rat liver to that in ruminant liver in order to interpret experimental observations in ruminants. Of perhaps greater interest is the recognition that the adaptations in the ruminant system are important not only in enabling us to rationalize the physiological changes observed in ruminants, but are in themselves of interest in the analysis of metabolic regulatory strategies. Consequently, this review deals with the peculiarities of the regulation of hepatic ketogenesis in ruminants, and the biochemical mechanisms that may explain their existence.
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Huang, Xiao Dan, Gonzalo Martinez-Fernandez, Jagadish Padmanabha, Ruijun Long, Stuart E. Denman i Christopher S. McSweeney. "Methanogen Diversity in Indigenous and Introduced Ruminant Species on the Tibetan Plateau". Archaea 2016 (2016): 1–10. http://dx.doi.org/10.1155/2016/5916067.
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Host factors are regarded as important in shaping the archaeal community in the rumen but few controlled studies have been performed to demonstrate this across host species under the same environmental conditions. A study was designed to investigate the structure of the methanogen community in the rumen of two indigenous (yak and Tibetan sheep) and two introduced domestic ruminant (cattle and crossbred sheep) species raised and fed under similar conditions on the high altitude Tibetan Plateau. The methylotrophic Methanomassiliicoccaceae was the predominant archaeal group in all animals even thoughMethanobrevibacterare usually present in greater abundance in ruminants globally. Furthermore, within the Methanomassiliicoccaceae family members fromMmc.group 10 andMmc.group 4 were dominant in Tibetan Plateau ruminants compared toMmc.group 12 found to be highest in other ruminants studied. Small ruminants presented the highest number of sequences that belonged to Methanomassiliicoccaceae compared to the larger ruminants. Although the methanogen community structure was different among the ruminant species, there were striking similarities between the animals in this environment. This indicates that factors such as the extreme environmental conditions and diet on the Tibetan Plateau might have a greater impact on rumen methanogen community compared to host differences.
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Ogolla, Kennedy O., Judith K. Chemuliti, Mariah Ngutu, Winnie W. Kimani, Douglas N. Anyona, Isaac K. Nyamongo i Salome A. Bukachi. "Women’s empowerment and intra-household gender dynamics and practices around sheep and goat production in South East Kenya". PLOS ONE 17, nr 8 (4.08.2022): e0269243. http://dx.doi.org/10.1371/journal.pone.0269243.
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Small ruminant production facets like decision-making, ownership, labour allocation, access to- and control over assets are gendered. This study investigates intra-household gender dynamics and practices around sheep and goat production among smallholder farmers in South East region of Kenya. A quantitative study was conducted on 358 dual-headed (married) households to generate gender-disaggregated data on ownership, decision-making and labour allocation around small ruminant production. Qualitative data was collected through focused group discussions to bring out the community perspectives. From the findings, the average number of small ruminants owned by the households as reported by men was slightly higher than women. The average number of small ruminants solely owned by men was significantly higher than by women. Men reported a relatively higher number of jointly owned small ruminants compared to women. More women than men reported that they could give as a gift, sell-off and slaughter jointly owned small ruminants without consulting their spouses. Small ruminants were considered the most important livestock asset in supporting a household’s livelihood by relatively more women than men. Men had more decision-making autonomy over jointly owned small ruminants compared to women. Production tasks around small ruminants such as feeding, watering, selling milk and cleaning housing structures were mostly performed by the women. Qualitative data identified men as the de facto owners of small ruminants with a higher power position in making the important production decisions. The study offers three implications on the design of livestock interventions to empower women, the interventions should ensure that; 1) women are not just owners of livestock assets but also share power and decision-making rights in all aspects of production, 2) production labour is shared equitably between men and women and, 3) women access benefits from livestock production even when animals are owned by men.
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Caja, Gerardo, Andreia Castro-Costa, Ahmed A. K. Salama, Joan Oliver, Mario Baratta, Carles Ferrer i Christopher H. Knight. "Sensing solutions for improving the performance, health and wellbeing of small ruminants". Journal of Dairy Research 87, S1 (30.07.2020): 34–46. http://dx.doi.org/10.1017/s0022029920000667.
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AbstractDiversity of production systems and specific socio-economic barriers are key reasons explaining why the implementation of new technologies in small ruminants, despite being needed and beneficial for farmers, is harder than in other livestock species. There are, however, helpful peculiarities where small ruminants are concerned: the compulsory use of electronic identification created a unique scenario in Europe in which all small ruminant breeding stock became searchable by appropriate sensing solutions, and the largest small ruminant population in the world is located in Asia, close to the areas producing new technologies. Notwithstanding, only a few research initiatives and literature reviews have addressed the development of new technologies in small ruminants. This Research Reflection focuses on small ruminants (with emphasis on dairy goats and sheep) and reviews in a non-exhaustive way the basic concepts, the currently available sensor solutions and the structure and elements needed for the implementation of sensor-based husbandry decision support. Finally, some examples of results obtained using several sensor solutions adapted from large animals or newly developed for small ruminants are discussed. Significant room for improvement is recognized and a large number of multiple-sensor solutions are expected to be developed in the relatively near future.
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Oliveira, Dimas Estrasulas de, i Sila Carneiro da Silva. "Alkanes as markers in nutritional studies with wild ruminant and non-ruminant animals". Scientia Agricola 64, nr 6 (grudzień 2007): 657–62. http://dx.doi.org/10.1590/s0103-90162007000600015.
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Knowledge of information relative to the digestibility, intake and botanical and morphological composition of the diet is important in nutritional studies, since it provides the basis for understanding aspects related to the ingestive behavior and selectivity of animals. N-alkanes have been used successfully as markers in studies with many species of animals, particularly domesticated ruminants, most of the times as replacements for conventional markers as chromium oxide for example. However, for wild ruminants and non-ruminant animals information on this technique is still scarce and, as a consequence, its potential for use unknown. This review reports the use of this technique in studies of feed digestibility, intake and diet composition with wild ruminants and non-ruminant animals, summarizing results and inferring on the feasibility and applicability of the technique.
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Sun, Kang, Huihui Liu, Huiyu Fan, Ting Liu i Chen Zheng. "Research progress on the application of feed additives in ruminal methane emission reduction: a review". PeerJ 9 (31.03.2021): e11151. http://dx.doi.org/10.7717/peerj.11151.
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Background Ruminal methane (CH4) emissions from ruminants not only pollute the environment and exacerbate the greenhouse effect, but also cause animal energy losses and low production efficiency. Consequently, it is necessary to find ways of reducing methane emissions in ruminants. Studies have reported that feed additives such as nitrogen-containing compounds, probiotics, prebiotics, and plant extracts significantly reduce ruminant methane; however, systematic reviews of such studies are lacking. The present article summarizes research over the past five years on the effects of nitrogen-containing compounds, probiotics, probiotics, and plant extracts on methane emissions in ruminants. The paper could provide theoretical support and guide future research in animal production and global warming mitigation. Methods This review uses the Web of Science database to search keywords related to ruminants and methane reduction in the past five years, and uses Sci-Hub, PubMed, etc. as auxiliary searchers. Read, filter, list, and summarize all the retrieved documents, and finally complete this article. Results Most of the extracts can not only significantly reduce CH4 greenhouse gas emissions, but they will not cause negative effects on animal and human health either. Therefore, this article reviews the mechanisms of CH4 production in ruminants and the application and effects of N-containing compounds, probiotics, prebiotics, and plant extracts on CH4 emission reduction in ruminants based on published studies over the past 5 years. Conclusion Our review provides a theoretical basis for future research and the application of feed additives in ruminant CH4 emission reduction activities.
Rozprawy doktorskie na temat "Ruminants"
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Narciso, Luis Gustavo. "Impacto de diferentes protocolos de corticoterapia antenatal para obtenção de cabritos prematuros viáveis". Universidade Estadual Paulista (UNESP), 2018. http://hdl.handle.net/11449/152986.
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
Determinaram-se a vitalidade e os perfis hematológicos, hemogasométricos e bioquímicos de 37 cabritos prematuros com, aproximadamente, 141 dias de vida intrauterina, oriundos de cabras submetidas a diferentes protocolos de corticoterapia, a saber: Grupo I -Constituído por dez cabritos com ± 141 dias de vida intrauterina, nascidos por meio de cesarianas, de cabras que receberam, por via intramuscular (IM) em dose única, 20 mg de dexametasona, dois dias antes da cirurgia eletiva (139 dias); Grupo II - Composto por nove cabritos com ± 141 dias de vida intrauterina, nascidos por meio de cesarianas, de mães que receberam, por via IM/SID, a saber : 2 mg de dexametasona, dos 133 aos 136 dias de gestação; 4 mg dos 137 aos 139; e 20 mg aos 140 dias de prenhez; Grupo III - constituído por nove cabritos com ± 141 dias de vida intrauterina, nascidos por meio de cesarianas, de cabras que receberam, por via IM/BID, 16 mg de dexametasona aos 139, com doses repetidas a cada 12 horas até a cirurgia eletiva; e Grupo IV - composto por nove cabritos com ± 141 dias de vida intrauterina, nascidos por meio de cesarianas, de cabras que receberam 4, 8, 16 e 20 mg de dexametasona, por via IM/SID, aos 137, 138, 139 e 140 dias de gestação, respectivamente. Os mesmos foram avaliados no que tange à vitalidade, pelo escore APGAR. Obtiveram-se amostras sanguíneas de cabritos ao nascimento, aos 60 minutos, às 12, 24 e às 48 horas, visando à determinação do hemograma, como também das variáveis hemogasométricas, insulina, cortisol, ureia, creatinina, glicose e lactato séricos, bem como da atividade sérica de gamaglutamiltransferase e da concentração de proteína total. Para determinação e avaliação das taxas e das possíveis causas de morbimortalidade, os recém-nascidos foram observados até os 30 dias de vida
Was determined the vitality and hematological profiles, hemogasometrics and biochemists of 37 kids approximately premature 141 days of intrauterine life, from goats subjected to different treatment protocols, namely: Group I- Consisting of ten goats with ± 141 days old, born through c-section, of goats that will receive, intramuscularly (IM) and once, 20 mg of dexamethasone, two days prior to elective surgery (139 days); Group II-composed of nine goats with ± 141 days old, born through c-section, of mothers who receive, via IM/SID: 2 mg of dexamethasone, 133 to 136 days of gestation; 4 mg of 137 to 139; and 20 mg to 140 days of pregnancy; Group III-consisting of nine goats with ± 141 days old, born through c-section, of goats that will receive, via IM/IDB, 16 mg of dexamethasone to 139, with repeated doses every 12 hours before elective surgery; and Group IV-composed of nine goats with ± 141 days old, born through c-section, of goats will receive 4, 8, 16 and 20 mg of dexamethasone, via IM/SID, to 137, 138, 139 and 140 days of gestation, respectively. The same will be evaluated with respect to vitality, APGAR score. This will give blood samples from goats at birth, to 60 minutes, at 12, 24 and 48 hours, aiming at determining the CBC, as well as the variables hemogasometrics, insulin, cortisol, urea, creatinine, serum lactate and glucose, as well as the Serum activity of associated disease and the concentration of total protein.For determination and assessment fees and the possible causes of morbidity and mortality, the newborns will be observed until the 30 days of life. Keywords: ruminants, dexamethasone, induced childbirth
FAPESP: 16/00808-6
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Morello, Amábile França. "Influência das lactonas macrocíclicas utilizadas em bovinos no desenvolvimento de microrganismos e decomposição das fezes". Dracena, 2018. http://hdl.handle.net/11449/180726.
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Orientador: Ricardo Velludo Gomes de Soutello SoutelloResumo: Os parasitos influenciam de maneira significativa a bovinocultura no Brasil, sendo a aplicação de endectocidas da família das lactonas macrocíclicas umas das formas mais utilizadas para o controle, porém podem proporcionar contaminação ao ambiente, visto que sua eliminação é principalmente via fezes e urina. Com isto, este trabalho objetivou verificar o desenvolvimento de microrganismos edáficos e a decomposição das fezes de bovinos ao longo do tempo após o tratamento com diferentes lactonas macrocíclicas. Foram avaliadas as fezes de doze animais, divididos em quatro grupos homogêneos, sendo o G1- controle (sem a administração de endectocida), G2-Ivermectina 1%, G3-Ivermectina 3,15% e G4- Moxidectina 1%. As colheitas das fezes dos animais foram realizadas nos dias 0, 7, 14, 21, 28,42 e 56 pós tratamento, e submetidas a três ambientes de decomposição, sendo ambiente controlado (BOD), Natural (NAT): exposto as condições climáticas naturais e enterradas no solo (Solo). Nos dias das cada colheitas e 112 dias após cada colheita, foi realizada a avaliação matéria orgânica. As avaliações da microbiota das fezes foram realizadas nos dias das colheitas e 7 após cada colheita. Observou-se que as ivermectinas em suas duas concentrações (1 e 3,15%) interferiram no desenvolvimento da população microbiana, já a moxidectina 1% não alterou a dinâmica populacional das bactérias, que também não foi influenciada pelo ambiente exposto em nenhum dos tratamento. A decomposição não foi afetada pela... (Resumo completo, clicar acesso eletrônico abaixo)
Mestre
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Morrison, Christopher D. "Leptin and neuropeptide Y as a link between body fat, fertility and appetite in ruminants /". free to MU campus, to others for purchase, 2001. http://wwwlib.umi.com/cr/mo/fullcit?p3025641.
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Gonçalves, Joana Isabel Ribeiro da Costa. "Laparoscopia em ruminantes : utilização de uma técnica mini-invasiva na correcção do deslocamento do abomaso à esquerda". Master's thesis, Universidade Técnica de Lisboa. Faculdade de Medicina Veterinária, 2011. http://hdl.handle.net/10400.5/3621.
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Dissertação de Mestrado Integrado em Medicina VeterináriaO objectivo deste trabalho é descrever as principais aplicações da laparoscopia em ruminantes e o uso desta técnica na correcção do deslocamento abomasal, de forma regular, na clínica de animais de pecuária. A área da endoscopia tem tido uma evolução notável nas últimas décadas, para a qual têm também contribuído os avanços verificados a nível tecnológico. Em laparoscopia de ruminantes são geralmente usados laparoscópios rígidos e as principais vantagens desta cirurgia incluem o facto de ser mini-invasiva, a redução da duração do procedimento, poucas complicações e tempo de recuperação pós-cirúrgico mais curto. As principais desvantagens incluem o preço do equipamento, a curva de aprendizagem e a perda de sensação táctil em comparação com a cirurgia aberta. São indicados neste trabalho os tipos de equipamento comummente usados e sugestões de cuidados pré e pós cirúrgicos. A anatomia abdominal observada através do laparoscópio e possíveis abordagens cirúrgicas são também referidas. No que diz respeito ao deslocamento abomasal, para além de várias técnicas disponíveis para a sua correcção, é descrita a patogenia da doença, os factores de risco, a influência de doenças concomitantes e é apresentado um conjunto de casos observados na Clínica para Ruminantes (medicina interna e cirurgia) em Gießen submetidos a cirurgia laparoscópica segundo o método de Janowitz. A abomasopéxia por meio de colocação de toggle abomasal, seja pelo método de Janowitz, Christiansen ou Newman, Anderson e Silveira, são técnicas que podem ser praticadas com facilidade na clínica de campo.
ABSTRACT - Laparoscopy in ruminants: using a mini-invasive procedure for correction of the leftsided displaced abomasum. - The aim of this dissertation is to describe the main applications of laparoscopy in ruminants and the use of this method for the correction of the displaced abomasum, in a regular basis, in farm animals’ practice. The evolution on the endoscopy field during the past decades was remarkable, for what is also important the great advances verified in technology area. Rigid laparoscopes are commonly used in ruminants’ laparoscopy. Some advantages that are related with this kind of surgery are the mini-invasiveness, the reduction of the surgical time, the few complications and a recovery period faster than with conventional surgery. The main drawbacks are the price of the equipment, the learning curve and the lost of the tactile sensation comparing with open surgery. In this paper, there is a review of the equipment commonly used and some suggestions for pre and post-surgical care. The laparoscopic abdominal anatomy and some possible approaches are also referred. About the abomasum displacement, a description of various techniques used on its correction is
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Galbraith, Jayson Kent. "Methane production in native ruminants". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp04/mq22596.pdf.
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Suarez, Victor Humberto. "L'Interfécondité des Ostertagiinae des Ruminants". Montpellier 2, 1990. http://www.theses.fr/1990MON20209.
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L'interfecondation des parasites de la sous-famille des ostertagiinae (lopez neyra, 1947), nematode trichostrongyloidea, des ruminants est etudie. La methodologie d'etude repose sur l'appariement de femelles vierges de souches monomorphes d'une espece avec des males d'une autre espece. Des ovins fistules de la caillette et traites avec des corticoides a action prolongee sont utilises comme recepteur des nematodes. L'evaluation des resultats se fait a partir de l'absence ou de la presence d'ufs dans les feces, des possibilites de developpement en larves infestantes, puis en adultes, fertiles ou non. Nous n'avons pas obtenu l'hybride intergenerique mais un hybride interspecifique entre o. Leptospicularis et o. Ostertagi. Il n'y a pas de barrieres reproductives entre o. Leptospicularis et o. Kolchida, o. Ostertagi et o. Lyrata et t. Circumcincta et t. Trifurcata: l'interfecondite de ces nematodes, deja regroupes en couples par des analyses multidimensionnelles par leurs ressemblances selon l'environnement et l'hote, confirme l'existence de polymorphisme. Le determinisme genetique du polymorphisme est envisage a partir de l'etude de l'evolution des frequences phenotypiques des souches de laboratoire et a partir de croisements selectifs
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Santos, Isabella Barbosa dos. "Viabilidade do parasitismo por Haemonchus placei em caprinos (Capra hircus) experimentalmente infectados". Universidade Estadual Paulista (UNESP), 2018. http://hdl.handle.net/11449/153384.
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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
A caprinocultura é considerada um segmento de grande importância em agronegócios no país, gerando importante fonte de carne e leite, principalmente na região Nordeste. Entretanto, este criatório sofre grandes perdas econômicas devido às parasitoses que acometem o trato digestório. Dentre estas, destaca-se, o gênero Haemonchus, cujas espécies H. contortus e H. placei parasitam abomaso de caprinos e bovinos, respectivamente, havendo possibilidade de infecção cruzada dessas duas espécies helmínticas. O objetivo do presente estudo foi avaliar a viabilidade do parasitismo por H. placei em caprinos e compará-la à patogenicidade por H. contortus. Foram utilizados 14 caprinos, recém-nascidos, mantidos em gaiolas metálicas de piso suspenso, assim distribuídos: GI - quatro cabritos inoculados com 5000 larvas infectantes (L3) de H. placei, GII – quatro infectados com 5000 larvas infectantes (L3) de H. contortus, GIII – quatro animais inoculados com 2500 larvas L3 de H. contortus + 2500 H. placei e GIV – dois cabritos que receberam apenas água (controle). Exames de contagem de ovos de estrongilídeos por grama de fezes (OPG) foram realizados diariamente, após o 7º dia da inoculação. Os períodos pré-patentes foram de 24 dias para H contortus e de 31 dias para H. placei. O grupo inoculado apenas com H. placei apresentou médias de OPG inferiores quando comparado aos demais grupos. Decorridos 42 dias pós-infecção, os 14 caprinos foram eutanasiados e necropsiados, sendo coletados “in totum” os exemplares de Haemonchus. O grupo I apresentou média de 25,5 espécimes H. placei, o grupo II média de 619,5 de exemplares de H. contortus, o grupo III média de 120 exemplares de H. placei e 604,75 de H. contortus e no grupo IV nenhum helminto foi diagnosticado. Não foram constatadas quaisquer outras espécies e nem formas imaturas de Haemonchus no trato gastrintestinais dos caprinos. Fragmentos do abomaso foram coletados e armazenados em formol tamponado para análise histopatológica. Foram observados no grupo I lesões microscópicas leves apenas com poucos focos inflamatórios. Nos grupos II e III foram diagnosticadas lesões extensas, como edemas, focos inflamatórios difusos, infiltrado de eosinófilos, diminuição das células parietais. No grupo IV nenhuma alteração histopatológica foi diagnosticada. Nas condições desse estudo, a espécie caprina foi razoavelmente susceptível ao parasitismo por Haemonchus placei, sendo esse parasitismo mais proeminente nos animais que receberam infecção mista (H. placei + H. contortus).
Goat breeding is considered a very important segment in Brazilian agribusiness, generating a significant source of meat and milk. However, this industry suffers great economic losses due to parasitic diseases that affect the digestive tract, compromising their development. Among these, the Haemonchus genus stands out, with H. contortus and H. placei parasitizing goats and cattle, respectively, with the possiblity of cross infection between these helminth species in abomasu of hosts. The objective of the present study was to estimate the viability of H. placei parasitism in goats, and compare it with H. contortus pathogenicity. Fourteen newborn goats were used, distributed in the following way: GI - four goats inoculated with infective larvae (L3) of H. placei; GII – four animals infected with infective larvae (L3) of H. contortus; GIII - four caprines inoculated with larvae L3 of H. contortus + H. placei; and GIV - two goats that received only water (control). Each animal received 5000 L3 of Haemonchus species, in a single dose, orally. Egg per Gram of Feces (EPG) exams were performed daily after the 7th day of inoculation, establishing that the pre-patent period of H. contortus was 24 days and H. placei was 31 days. The group inoculated only with H. placei presented lower EPG means when compared to the other groups. After 42 days post-infection, all 14 goats were euthanized and necropsied, and Haemonchus specimens were collected “in totum". Group I presented an average of 25.5 specimens, while the mean of group II was 619.5, group III obtained an average of 120 specimens of H. placei and 604.75 of H. contortus and group IV did not present any specimens. No other species and no immature forms of Haemonchus were found in gastrintestinal tracts of experimental animals. Fragments of abomasum were collected and stored in buffered formalin for histopathological analysis, in which GI group showed mild microscopic lesions with only a few inflammatory foci, while groups II and III had extensive lesions, such as edema, diffuse inflammatory foci, eosinophilic infiltrate and hyperplasia of parietal cells. Group IV showed no changes. Under conditions of this study, the caprine species did not present itself as susceptible to parasitism by Haemonchus placei, with such parasitism being more prominent when in consortium with Haemonchus contortus.
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Silva, Eva Liliane dos Santos. "Impacto de diferentes protocolos de corticoterapia antenatal na produção de hidroperóxidos e na capacidade antioxidante em cabritos e cabras pós-parto". Universidade Estadual Paulista (UNESP), 2018. http://hdl.handle.net/11449/154752.
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
Este trabalho teve como objetivo mensurar a produção de hidroperóxidos e a capacidade antioxidante do plasma de cabras e seus cabritos, por meio do teste d-ROMs (Reactive Oxygen Metabolites) e BAP (Biological Antioxidant Potential), após as cabras serem submetidas a diferentes protocolos de corticoterapia antenatal, os animais foram aleatoriamente alocados em quatro grupos experimentais: grupo I - constituído por quatro cabras e sete cabritos, com uma única dosagem de 20 mg de dexametasona, por via IM/SID, dois dias antes da cirurgia eletiva (139 dias); grupo II - composto por quatro cabras e seis cabritos utilizando a dosagem de 2 mg de dexametasona, dos 133 aos 136 dias; 4 mg dos 137 aos 138; e 20 mg aos 139 dias de prenhes, por via IM/SID; grupo III - constituído por quatro cabras e sete cabritos, com dosagem de 16 mg de dexametasona aos 139, com doses repetidas a cada 12 horas até a cirurgia eletiva, por via IM/BID, e grupo IV - composto por quatro cabras e seis cabritos utilizando a dose de 4, 8, 16 e 20 mg de dexametasona, por via IM/SID, aos 137, 138, 139, 140 dias de gestação, respectivamente. Para analisar d-ROMs e BAP foram feitas coletas de sangue nas cabras por punção da veia jugular aos 15 minutos (M15) após o parto, e nos cabritos foram realizadas as coletas de sangue por punção da veia jugular nos respectivos momentos com referência ao nascimento de cada neonato: 15 minutos (M15), 24 horas (M24) e 48 horas (M48).
The objective of this work was to measure the production of hydroperoxides and the antioxidant capacity of goats and their goats by means of the d-ROMs test (Reactive Oxygen Metabolites) and BAP (Biological Antioxidant Potential), after the goats were submitted to different protocols of antenatal corticosteroid therapy, the animals were randomly assigned to four experimental groups: group I - consisting of four goats and seven goats, with a single dose of 20 mg of dexamethasone, IM / SID, two days before elective surgery (139 days); group II - composed of four goats and six goats using the dosage of 2 mg dexamethasone, from 133 to 136 days; 4 mg of 137 to 138; and 20 mg at 139 days of pregnancy, by IM/SID; group III - consisting of four goats and seven goats, with a dose of 16 mg of dexamethasone at 139, with repeated doses every 12 hours until elective surgery, by IM/BID, e group IV - composed of four goats and six goats using the dose of 4, 8, 16 and 20 mg dexamethasone, by IM / SID route, to the 137, 138, 139, 140 days of gestation, respectively. Blood samples were taken from the goats by puncture of the jugular vein at 15 minutes (M15) after calving and the kidneys were collected by puncturing the jugular vein at the respective moments with reference to the birth of each neonate: 15 minutes (M15), 24 hours (M24) and 48 hours (M48).
FAPESP: 16/00808-6
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Nascimento, Priscilla Marques do. "Metabolismo oxidativo e perfil bioquímico de ovelhas Santa Inês no período periparto: efeito da suplementação com vitamina E". Universidade de São Paulo, 2012. http://www.teses.usp.br/teses/disponiveis/10/10136/tde-12082014-133356/.
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Para avaliar o metabolismo oxidativo, perfil bioquímico e o efeito da suplementação com vitamina E intramuscular no período periparto, foram utilizadas 24 ovelhas, hígidas, da raça Santa Inês, no último mês de gestação. As ovelhas foram distribuídas em dois grupos que receberam, com intervalo de 14 dias, duas aplicações pela via intramuscular profunda de 2 mL de solução fisiológica (grupo controle-GC), ou 200 UI de vitamina E (grupo tratado-GT). Estes grupos foram subdivididos em P1 e P2. No P1, as ovelhas receberam a segunda dose de solução fisiológica ou vitamina entre 1 e 7 dias da data do parto. No P2, a segunda dose foi administrada entre 15 e 25 dias da data do parto. As amostras de sangue foram coletadas nos seguintes momentos: previamente à primeira aplicação (M0), 15 dias após a primeira aplicação (M1), no momento do parto (M2), 7 dias após o parto (M3), duas semanas após o parto (M4) e 4 semanas após o parto (M5). Foram analisadas as variáveis do perfil bioquímico: proteína total, albumina, globulina, uréia, creatinina, creatinofosfoquinase (cK), ácido úrico, aspartatoaminotransferase (AST), gamaglutamiltransferase (GGT), colesterol, triglicérides, glicose, beta hidroxibutirato (BHB) , ácidos graxos não esterificados (NEFA). Do metabolismo oxidativo foram determinas as atividades da superóxido dismutase (SOD), glutationa peroxidase (GSH-Px), glutationa reduzida (GSH) e habilidade de redução férrica plasmática (HRFP). Em P1, não foram observadas diferenças entre os grupos tratado e controle nas concentrações de proteína total, globulina, cK, ácido úrico, glicose, triglicérides, BHB, NEFA, SOD, GSH-Px e GSH. Porém em P1, foram observadas maiores concentrações em de albumina em M0 (P=0,039); uréia em M1 (P=0,018), M2 (P=0,005) e M3 (P=0,040); a creatinina em M2 (P=0,030) e M3 (P=0,047); GGT em M1 (P= 0,01) e M2 (P=0,024); colesterol em M2 (P=0,041) e HRFP em M3 (P= 0,022) para as ovelhas tratadas em relação às controle. Em P1, a AST foi maior para o controle em relação ao tratado em M2 (P=0,030). Em P2, foram observadas maiores atividades para o grupo controle nas variáveis SOD em M3 (P=0,013) e GSH-Px em M4 (P=0,027) e maior HRFP em M4 (P=0,023) para o grupo tratado. A aplicação de duas doses de vitamina E (200 UI, via IM) aumentou as concentrações de HRFP no pós-parto tanto em P1 como em P2.Oxidative metabolism, biochemical profile and the effect of intramuscular vitamin E supplementation on sheeps per partum period were evaluated using 24 healthy Santa Ines sheep, in the last month of pregnancy. The lambs were randomly divided into two groups, control group-CG and treated group-TG. CG received 2 mL of saline and TG received 200 IU of vitamin E, both treatments were done with two doses within interval of 14 days, by deep intramuscular injection of. These groups were further divided into P1 and P2. In P1 the sheep received the second or vitamin saline dose between 1 and 7 days before delivery date. In P2, the second dose was administered between 15 and 25 days before delivery. Blood samples were collected at the following times: before the first application (M0), 15 days after (M1), at birth (M2), 7 days postpartum (M3), two weeks after delivery (M4) and four weeks after delivery (M5). The variables of biochemical profile analyzed were: total protein, albumin, globulin, urea, creatinine, creatine kinase (CK), uric acid, aspartate aminotransferase (AST), gamma-glutamyltransferase (GGT), cholesterol, triglycerides, glucose, beta hydroxybutyrate (BHB), acids non-esterified fatty acids (NEFA). Oxidative metabolism variable were: activities of superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), reduced glutathione (GSH) and ferric reducing ability of plasma (HRFP). No differences were observed between the P1 treated and control groups in the concentrations of total protein, globulin, CK, uric acid, glucose, triglycerides, BHB, NEFA, SOD, GSH-Px and GSH. However higher concentrations of albumin in M0 (P = 0.039), urea in M1 (P = 0.018), M2 (P = 0.005) and M3 (P = 0.040), creatinine in M2 (P = 0.030 ) and M3 (P = 0.047), GGT in M1 (P = 0.01) and M2 (P = 0.024), cholesterol in M2 (P = 0.041) and HRFP at M3 (P = 0.022) for ewes treated we observed. AST concentration was greater for control in M2 (P = 0.030). In P2, higher activities were observed for the control group in the variables SOD in M3 (P = 0.013), GSH-Px in M4 (P = 0.027) and higher FRAP in M4 (P = 0.023) for the treated group. The application of two doses of vitamin E (200 IU, im) increased the concentrations of FRAP postpartum in both P1 and P2.
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Moreira, Tainá Silvestre. "Energy requirements, energetic partition and methane emission from growing Holstein, Gyr and F1 Holstein-Gyr dairy heifers". Universidade de São Paulo, 2016. http://www.teses.usp.br/teses/disponiveis/10/10135/tde-16112016-114843/.
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In Brazil, country with the fifth largest world production of milk, diets formulations are also carried out on the basis of nutritional requirements established in other countries, especially those from predominantly temperate climate. Research validation nutritional systems have evidenced application incompatibility of systems generated in temperate conditions at tropical conditions. Thus, the aim of this study was to determinate energy requirements, energetic partition and methane (CH4) enteric emission from growing Holstein, Gyr and F1 Holstein-Gyr dairy heifers in tropical conditions. The trial was conducted at The Multi-use Livestock Complex of Bioefficiency and Sustainability at Embrapa Dairy Cattle, Coronel Pacheco - MG, Brazil. Were evaluated 36 heifers, 12 Holstein, 12 Gyr and 12 Holstein-Gyr in 3 distinct experiments. In the first one, the 36 heifers were distributed in 12 latin squares, in a 3x3 factorial arrangement which was 3 nutritional plans and 3 genotypes. The nutritional plans were (1) 1.0x maintenance; (2) 1.5x maintenance and (3) 2.0x maintenance and the heifers were fed a diet consisting of 85.0% of corn silage and 15.0% of concentrate on a dry matter (DM) basis. Enteric CH4 emission was evaluated by SF6 tracer technique. Dry matter intake (DMI) and nutrients presented interaction among genotype and nutritional plan. Gyr heifers demonstrated higher crude protein (CP) digestibility (76.55%), F1 Holstein-Gyr intermediary value (75.14%) and Holstein animals presented the lowest value (74.59%). Daily CH4 production (g/d) was influenced by nutritional plan and differed as well between genotypes whereas Gyr heifers compared to the others had lesser CH4 emissions. Heifers fed at lower nutritional plan presented highest (85.5%) CH4 emissions by average daily gain (g/ kg of ADG) when compared to heifers fed at the higher nutritional plan. We found annual emissions of 45.84 kg of CH4. The second experiment has as objective measure the heat production (HP) and the enteric CH4 emission from dairy heifers using face mask (FM) method. The same animals, treatments and diets that were used in the first study were used in this second and third one. The HP expressed in Mcal by metabolic body weight (Mcal/BW0.75) was affect by genotype and Gyr heifers presented lower HP (163.2) when compared to Holstein (201.0) while F1 Holstein-Gyr heifers did not differ (181.3). Observed interaction among genotype and nutritional plan to CH4 emission in (g/d) and grams per kilo of metabolic body weight (g/kg of BW0.75). When expressed in dry matter ingested was not found genotype or nutritional plans effects to CH4 production. In the third study, our objective was to determine energy requirements, energetic partition and enteric CH4 emission using the \"gold standard\" methodology as calorimetric respirometry. Each heifers spent one 24 hours period in an open-circuit respirometric chamber (RC) to measurements. The CH4 emission was influenced by genotype and nutritional plan. Holstein and F1 Holstein-Gyr heifers demonstrated 73.4% superior emissions when compared to Gyr heifers. The net energy requirements for maintenance (NEm/kcal BW0.75) was 103.9 for Holstein heifers, 79.86 for Gyr heifers and 103.8 for F1 Holstein-Gyr heifers. The metabolizable energy requirements for maintenance (MEm/kcal BW0.75) was 132.6 for Holstein heifers, 116.0 for Gyr heifers and 138.2 for F1 Holstein-Gyr heifers. Were not found differences among Holstein and F1 heifers on NEm and MEm, so was formulated a combined equation for both, where the net and metabolizable energy requirements for maintenance were 105.2 and 135.0 kcal/BW0.75, respectively. We concluded that our results about nutritional requirements had similarity with available literature from respirometric chambers. These generated data from dairy cattle will be used for a future data base vising the establishment of feed patterns for representative dairy cattle genotypes in national herd composition. Also, the enteric methane emission data obtained in this study will be used in the greenhouse gases national inventory.No Brasil, país com a quinta maior produção mundial de leite, as formulações de dietas ainda são realizadas com base nas exigências nutricionais estabelecidas em países de clima predominantemente temperado. Pesquisas de validação de sistemas nutricionais têm evidenciado incompatibilidade de aplicação dos sistemas gerados em condições temperadas às condições tropicais. Assim, objetivou-se com o presente trabalho determinar as exigências de energia, a partição da energia consumida e emissão de metano (CH4) entérico de novilhas leiteiras em crescimento das raças Holandês, Gir e F1 Holandês-Gir, em condições tropicais. O experimento foi realizado no Complexo Experimental Multiusuário da Embrapa Gado de Leite, localizado no Campo Experimental José Henrique Bruschi, em Coronel Pacheco - MG. Foram avaliadas 36 novilhas leiteiras, sendo 12 da raça Holandês, 12 da raça Gir e 12 F1 Holandês-Gir em 3 experimentos distintos. No primeiro experimento, as 36 novilhas foram distribuídas em 12 quadrados latinos, em arranjo fatorial 3x3, ou seja, 3 planos nutricionais e 3 grupos genéticos. Os planos nutricionais foram (1) 1.0x mantença; (2) 1.5x mantença e (3) 2.0x mantença e as novilhas foram alimentadas com uma dieta constituída de 85.0% de silagem de milho e 15.0% de concentrado com base na matéria seca (MS). A metodologia empregada para mensuração de CH4 foi a técnica do gás traçador SF6. O consumo de matéria seca (CMS) e nutrientes apresentou interação entre genótipo e plano nutricional. Novilhas da raça Gir apresentam maior digestibilidade da proteína bruta (76,55%), as F1 Holandês-Gir valor intermediário (75,14%) enquanto que os animais da raça Holandês apresentaram o menor valor (74,59%). A produção diária de metano em grama dia (g/d) foi influenciada pelo plano nutricional e também diferiu entre grupo genético, sendo que novilhas da raça Gir quando comparadas às demais tiveram menor emissão de CH4 entérico. Novilhas alimentadas sob o menor plano nutricional apresentaram maior emissão de CH4 (85,5%) por ganho de peso diário (g/kg de GPD) quando comparada as novilhas sob o maior plano nutricional. A produção média de CH4 anual encontrada no presente estudo foi de 45,84 kg. O segundo experimento teve como objetivo mensurar a produção de calor (PC) e a emissão de CH4 entérico por novilhas leiteiras através do método da máscara facial. Os mesmos animais, tratamentos e dietas que foram utilizadas no primeiro estudo foram utilizados neste estudo e no estudo que será descrito posteriormente a esse. A PC expressa em Mcal por peso vivo metabólico (Mcal/PVM) foi afetada por genótipo e novilhas da raça Gir apresentaram menor PC (163,2) quando comparada as novilhas Holandês (201,0) enquanto que as novilhas F1 Holandês-Gir não diferiu das demais (181,3). Observou-se interação entre genótipo e plano nutricional para emissão de CH4 em grama dia e em grama por quilo de peso vivo metabólico. Quando expresso em relação à matéria seca ingerida, não foram encontrados efeitos de genótipo ou plano nutricional para emissão de CH4. O terceiro estudo objetivou determinar as exigências de energia, a partição energética e a emissão metano entérico pela metodologia padrão de respirometria calorimétrica. Cada novilha permaneceu por um período de 24 horas no interior da câmara para as mensurações. A emissão de CH4 (g/d) foi influenciada por genótipo e plano nutricional. Novilhas Holandês e F1 Holandês-Gir demonstram emissões superiores em 73,4% quando comparadas as novilhas da raça Gir. A exigência de energia líquida para mantença (ELm/kcal BW0,75) foi 103,9 para novilhas Holandês, 79,86 para novilhas Gir e 103,8 para novilhas F1 Holandês-Gir. A exigência de energia metabolizável para mantença (EMm/kcal BW0,75) foi 132, 6 para novilhas Holandês, 116,0 para novilhas Gir e 138,2 para novilhas F1 Holandês-Gir. Não foram encontradas diferenças entre novilhas Holandês e F1 Holandês-Gir para exigências de ELm e EMm, então foi formulada uma equação combinada para ambas, onde ELm e EMm foram 105,2 e 135,0 kcal/BW0,75, respectivamente. Concluiu-se que os atuais resultados de exigências em energia tiveram similaridade com a literatura disponível e serão utilizados para inclusão no banco de dados de gado de leite, a ser formado com trabalhos já existentes e outros que ainda serão desenvolvidos, visando ao futuro estabelecimento das normas e padrões nacionais de alimentação para bovinos leiteiros dos grupos genéticos mais representativos do rebanho nacional. Os dados de emissão de metano entérico obtidos poderão ser utilizados na elaboração do inventário nacional de emissão de gases de efeito estufa pelas atividades pecuárias.
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Nicholas, R., R. Ayling i L. McAuliffe, red. Mycoplasma diseases of ruminants. Wallingford: CABI, 2008. http://dx.doi.org/10.1079/9780851990125.0000.
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Ørskov, E. R. Energy nutrition in ruminants. London: Elsevier, 1990.
Znajdź pełny tekst źródłaCzęści książek na temat "Ruminants"
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Riebold, Thomas W. "Ruminants". W Veterinary Anesthesia and Analgesia, 912–27. Chichester, UK: John Wiley & Sons, Ltd, 2017. http://dx.doi.org/10.1002/9781119421375.ch49.
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Ishaq, Suzanne L., i André-Denis G. Wright. "Wild Ruminants". W Rumen Microbiology: From Evolution to Revolution, 37–45. New Delhi: Springer India, 2015. http://dx.doi.org/10.1007/978-81-322-2401-3_4.
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Chastain, C. B. "Small Ruminants". W Concise Textbook of Large Animal Handling, 207–42. Boca Raton: CRC Press, 2023. http://dx.doi.org/10.1201/9781003110910-6.
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Chesworth, J. M., T. Stuchbury i J. R. Scaife. "Digestion and Absorption in Ruminants and Non-Ruminants". W An Introduction to Agricultural Biochemistry, 395–411. Dordrecht: Springer Netherlands, 1998. http://dx.doi.org/10.1007/978-94-009-1441-4_28.
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Wallace, R. John, i C. James Newbold. "Probiotics for ruminants". W Probiotics, 317–53. Dordrecht: Springer Netherlands, 1992. http://dx.doi.org/10.1007/978-94-011-2364-8_12.
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Varshney, J. P. "Electrocardiography in Ruminants". W Electrocardiography in Veterinary Medicine, 245–59. Singapore: Springer Singapore, 2020. http://dx.doi.org/10.1007/978-981-15-3699-1_18.
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Kiara, Henry, Lucilla Steinaa, Vishvanath Nene i Nicholas Svitek. "Theileria in Ruminants". W Parasitic Protozoa of Farm Animals and Pets, 187–213. Cham: Springer International Publishing, 2017. http://dx.doi.org/10.1007/978-3-319-70132-5_8.
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Stilwell, G., A. Vieira, E. Can, C. Krug, S. Saraiva, M. Battini i S. Mattiello. "Ruminants’ Welfare Assessment". W Advances in Animal Health, Medicine and Production, 3–26. Cham: Springer International Publishing, 2020. http://dx.doi.org/10.1007/978-3-030-61981-7_1.
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McMurray, Cecil H. "Copper Deficiency in Ruminants". W Novartis Foundation Symposia, 183–207. Chichester, UK: John Wiley & Sons, Ltd., 2008. http://dx.doi.org/10.1002/9780470720622.ch10.
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Celi, Pietro. "Oxidative Stress in Ruminants". W Oxidative Stress in Applied Basic Research and Clinical Practice, 191–231. Totowa, NJ: Humana Press, 2011. http://dx.doi.org/10.1007/978-1-61779-071-3_13.
Pełny tekst źródłaStreszczenia konferencji na temat "Ruminants"
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Kapo, Naida, Jasmin Omeragić, Faruk Tandir, Indira Mujezinović, Ahmed Smajlović i Ermin Šaljić. "Anthelmintic Resistance in Gastrointestinal Nematodes of Ru-minants". W Socratic Lectures 7. University of Lubljana Press, 2022. http://dx.doi.org/10.55295/psl.2022.d9.
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Gastrointestinal nematode (GIN) infections remain one of the most prevalent and important issue affecting ruminants worldwide. Until date, the majority of GIN control has relied on the administra-tion of chemical anthelmintic medications on a regular basis, in recent years, the problem of anthel-mintic resistance has reached new heights where it can no longer be ignored as a major issue in the control of parasites of livestock. Anthelmintics are generally used at farmers' discretion, with no restrictions to access to commercially available drugs and without any assistance from veterinarians. Thus, inadequate use of anthelmintics is not rare, animals are often treated excessively, interfering with production, accelerating selection of resistant parasites, and posing significant problems for the ruminant industry. The unusually high frequency of multi-drug resistance (MDR) in sheep and goat nematodes threatens the sustainability of small-ruminant enterprises in several parts of the world. Although resistance in horses and cattle nematodes has not yet reached the levels reported in small ruminants, data shows that resistance issues, particularly MDR worms, are rising in these hosts. Both innovative non-chemical parasite control methods and molecular tests capable of detecting resistant worms are urgently needed. Keywords: Anthelmintics; Multidrug resistance; Gastrointestinal nematodes; Ruminants; Preva-lence
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Matovu, Jacob, i Ahmet Alçiçek. "Investigations and Concerns about the Fate of Transgenic DNA and Protein in Livestock". W International Students Science Congress. Izmir International Guest Student Association, 2021. http://dx.doi.org/10.52460/issc.2021.011.
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The fate of transgenic DNA (tDNA) and protein from feed derived from Genetically Modified organisms (GMOs) in animals has been a major issue since their commercialization in 1996. Several studies have investigated the risks of horizontal gene transfer (HGT) of tDNA and protein to bacteria or animal cells/tissues, but some of the reported data are controversial. Previous reports showed that tDNA fragments or proteins derived from GM plants could not be detected in tissues, fluids, or edible products from livestock. Other researchers have shown that there is a possibility of small fragments entering animal tissues, fluids and organs. This motivated us to update our knowledge about these concerns. Therefore, this review aimed to evaluate the probable transfer and accumulation of tDNA/proteins from transgenic feeds in animal samples (ruminant and non-ruminant) by evaluating the available experimental studies published scientifically. This study found that the tDNA/protein is not completely degraded during feed processing and digestion in Gastro-Intestinal Tract (GIT). In large ruminants (cattle), tDNA fragments/proteins were detected in GIT digesta, rumen fluid, and faeces. In small ruminants (goats), traces of tDNA/proteins were detected in GIT digesta, blood, milk, liver, kidney, heart and muscle. In pigs, they were detected in blood, spleen, liver, kidney, and GIT digesta. In poultry, traces were detected in blood, liver and GIT digesta but not in meat and eggs. Notwithstanding some studies that have shown transfer of tDNA/protein fragments in animal samples, we cannot rely on these few studies to give general evidence for transfer into tissues/fluids and organs of farm animals. However, this study clearly shows that transfer is possible. Therefore, intensive and authentic research should be conducted on GM plants before they are approved for commercial use, investigating issues such as the fate of tDNA or proteins and the effects of feeding GM feed to livestock.
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Stanković, Branislav, Slavča Hristov, Dejan Bugarski, Milan Ninković, Branislav Kureljušić, Miroslav Kjosevski i Ilias Chantziarase. "Implementation of biosecurity measures in ruminants farms". W Zbornik radova 26. medunarodni kongres Mediteranske federacije za zdravlje i produkciju preživara - FeMeSPRum. Poljoprivredni fakultet Novi Sad, 2024. http://dx.doi.org/10.5937/femesprumns24033s.
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Biosecurity is the result of all activities designed not only to prevent the introduction and spread of infectious diseases within and between herds, but ultimately to contribute to public health and food safety. Although experts and government agencies recommend the implementation of biosecurity practises on dairy, beef and sheep farms, their use appears to be limited. There is serious lack of training and consequently, rather low level of awareness of biosecurity risks among farmers. They are aware of necessity of good health of animals, but they mostly think of endemic diseases like mastitis, claws disorders, digestive problems, etc.). It seems that they are not aware of contagious disease risks, so pathogens models of spreading and entrance doors in to individual animal or population have to be pointed out. Farmers' opinion is that the government should have a greater input into biosecurity; veterinarians saw the ability or willingness of their clients to invest in biosecurity measures as a major barrier. Therefore, additional evidence of the effectiveness and/or potential economic benefits of proposed on-farm biosecurity measures have be better demonstrated. That would give a solid base for field veterinarians and their organisations to be more proactive in promotion and spreading of information on biosecurity, in both direct contact with farmers and organized training. This important role should be fulfilled in cooperation with farmers associations and veterinary authorities. A legal framework can be helpful, as well as stimulating measures for those who actively and successfully embrace biosecurity concept in their work. In many cases there are problems regarding biosecurity procedures application, particularly in control of movement of humans, animals, vehicles and equipment. Procedures have to be performed much more persistent and in responsible manner, particularly during summer, when field works take a lot of farmers' time. Biosecurity procedures must be more serious and determined as approaching to the object of protection.
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Silva, Filipe, Andreia Garcês, Catarina Magalhães i Isabel Pires. "Diseases in Ruminants Associated with Pteridium aquilinum Ingestion". W IECT 2023. Basel Switzerland: MDPI, 2023. http://dx.doi.org/10.3390/iect2023-14800.
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Muromtsev, A. B., A. Yu Efremov, S. V. Engashev i E. S. Engasheva. "TREMATODOSIS OF CATTLE AND SMALL CATTLE IN THE KALININGRAD REGION". W SPbVetScience. FSBEI HE St. Petersburg SUVM, 2023. http://dx.doi.org/10.52419/3006-2022-7-49-54.
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This article provides information on the distribution of trematodosis in cattle and small cattle, as well as the European red deer in the Kaliningrad region. A complex of therapeutic and prophylactic veterinary anthelmintic measures is described. The characteristics of domestic anthelmintics used to combat faststoliasis, dicroceliasis and paramphistomatosis are given. Their shortcomings and effectiveness are noted, modern approaches are proposed in the fight against trematodosis in ruminants through the use of new drugs: Fascocid, Iversan, Monizen, Helmicid, which allows for effective therapy and prevention of invasive diseases, avoiding losses of livestock products and increasing milk, meat and antler productivity of ruminants.
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Quental, Tiago B., i Matheus Januario. "AGE-DEPENDENT EXTINCTION IN RUMINANTS AT DIFFERENT TAXONOMICAL SCALES". W GSA Annual Meeting in Phoenix, Arizona, USA - 2019. Geological Society of America, 2019. http://dx.doi.org/10.1130/abs/2019am-336837.
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FARRE, M., J. KIM, A. A. PROSKURJAKOVA, Y. ZHANG, A. I. KULEMZINA, Q. LI, Y. ZHOU i in. "COEVOLUTION OF CHROMOSOME CHANGES AND GENE REGULATION IN RUMINANTS". W 5TH MOSCOW INTERNATIONAL CONFERENCE "MOLECULAR PHYLOGENETICSAND BIODIVERSITY BIOBANKING". TORUS PRESS, 2018. http://dx.doi.org/10.30826/molphy2018-04.
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Nyambo, Devotha G., Nguse Ngulumbi, Neema Mduma, Ramadhani Sinde i Tumaini Lyimo. "Machine learning model for predicting Peste des Petits Ruminants". W 2023 First International Conference on the Advancements of Artificial Intelligence in African Context (AAIAC). IEEE, 2023. http://dx.doi.org/10.1109/aaiac60008.2023.10465342.
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Ünlü, Elif Işılay, i Ahmet Çınar. "Lesion Detection on Skin Images Using Improved U-Net". W International Students Science Congress. Izmir International Guest Student Association, 2021. http://dx.doi.org/10.52460/issc.2021.022.
Pełny tekst źródłaStreszczenie:
The fate of transgenic DNA (tDNA) and protein of feeds from Genetically Modified organisms (GMOs) in animals has been an important topic since their commercialization in 1996. Several studies have investigated about risks of horizontal gene transfer (HGT) of tDNA and proteins to bacteria or animal cells/tissues, however, the reported data is at times controversial. Earlier reports showed that tDNA fragments or protein derived from GM plants have not been detected in tissues, fluids, or edible products of farm animals. Other researchers have come out to demonstrate that there is the possibility of small fragments leaking out into the animal tissues, fluids and organs. This motivated us to update our knowledge about these concerns. Therefore, this review aimed at assessing the likely transfer and accumulation of tDNA/ proteins from transgenic feeds to animal (ruminants and non-ruminants) samples through evaluating the available experimental scientific published studies. This study has found out that the tDNA or protein is not completely degraded during feed processing and digestion in the Gastro-Intestinal Tract (GIT). In large ruminants (Cattle), tDNA fragments/protein have been detected in the GIT digesta, ruminal fluid and feces. In small ruminants (Goats), traces of tDNA/proteins have been detected in the GIT digesta, blood, milk, liver, kidney, heart and muscle. In pigs, they have been detected in blood, spleen, liver kidney and in the GIT digesta. In poultry, traces have been seen in blood, liver and GIT digesta but not in meat and Eggs. Regardless of some studies that have shown the transfer of tDNA/protein fragments to animal samples, we cannot base on these few studies to give a piece of general evidence about their transfer into tissues/fluids and organs of livestock animals. However, this study clearly shows possible transfer, hence intensive and authentic research on GM crops should be done before they are allowed for commercial use, studying issues like the fate of tDNA or proteins and the effect of feeding GM feeds to livestock.
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Fioranelli, Francesco, Haobo Li, Julien Le Kernec, Valentina Busin, Nicholas Jonsson, George King, Martin Tomlinson i Lorenzo Viora. "Radar-based evaluation of lameness detection in ruminants: preliminary results". W 2019 IEEE MTT-S International Microwave Biomedical Conference (IMBioC). IEEE, 2019. http://dx.doi.org/10.1109/imbioc.2019.8777830.
Pełny tekst źródłaRaporty organizacyjne na temat "Ruminants"
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Ellis, William, i Daniel Ben Ghedalia. Dynamics of Digestion in Ruminants. United States Department of Agriculture, październik 1988. http://dx.doi.org/10.32747/1988.7695598.bard.
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Ludena, Carlos, Thomas Hertel, Paul Preckel, Kenneth Foster i Alejandro Nin-Pratt. Productivity Growth and Convergence in Crop, Ruminant and Non-Ruminant Production: Measurement and Forecasts. GTAP Working Paper, listopad 2006. http://dx.doi.org/10.21642/gtap.wp35.
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There is considerable interest in projections of future productivity growth in agriculture. Whether one is interested in the outlook for global commodity markets, future patterns of international trade, or the interactions between land use, deforestation and ecological diversity, the rate of productivity growth in agriculture is an essential input. Yet solid projections for this variable have proven elusive – particularly on a global basis. This is due, in no small part, to the difficulty in measuring historical productivity growth. The purpose of this paper is to report the latest time series evidence on total factor productivity growth for crops, ruminants and non-ruminant livestock, on a global basis. We then follow with tests for convergence amongst regions, providing forecasts for farm productivity growth to the year 2040. The results suggest that most regions in the sample are likely to experience larger productivity gains in livestock than in crops. Within livestock, the non-ruminant sector is expected to continue to be more dynamic than the ruminant sector. Given the rapid rates of productivity growth observed recently, non-ruminant and crop productivity in developing countries may be converging to the productivity levels of developed countries. For ruminants, the results show that productivity levels may be diverging between developed and developing countries.
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Forte, Vincent A., Devine Jr., Cymerman James A. i Allen. Research Stanchion and Transporter for Small Ruminants. Fort Belvoir, VA: Defense Technical Information Center, marzec 1988. http://dx.doi.org/10.21236/ada195103.
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Boisclair, Yves R., i Arieh Gertler. Development and Use of Leptin Receptor Antagonists to Increase Appetite and Adaptive Metabolism in Ruminants. United States Department of Agriculture, styczeń 2012. http://dx.doi.org/10.32747/2012.7697120.bard.
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Objectives The original project had 2 major objectives: (1) To determine the effects of centrally administered leptin antagonist on appetite and adaptive metabolism in the sheep; (2) To develop and prepare second-generation leptin antagonists combining high binding affinity and prolonged in vivo half-life. Background Periods of suboptimal nutrition or exaggerated metabolic activity demands lead to a state of chronic energy insufficiency. Ruminants remain productive for a surprisingly long period of time under these circumstances by evoking adaptations sparing available energy and nutrients. The mechanism driving these adaptations in ruminant remains unknown, but could involve a reduction in plasma leptin, a hormone acting predominantly in the brain. In laboratory animals, reduced leptin signaling promotes survival during nutritional insufficiency by triggering energy sparing adaptations such as reduced thyroid hormone production and insulin resistance. Our overall hypothesis is that similar adaptations are triggered by reduced leptin signaling in the brain of ruminants. Testing of this hypothesis in ruminants has not been possible due to inability to block the actions of endogenous leptin and access to ruminant models where leptin antagonistic therapy is feasible and effective. Major achievements and conclusions The Israeli team had previously mutated 3 residues in ovine leptin, with no effect on receptor binding. This mutant was renamed ovine leptin antagonist (OLA) because it cannot activate signaling and therefore antagonizes the ability of wild type leptin to activate its receptor. To transform OLA into an effective in vivo antagonist, the Israeli made 2 important technical advances. First, it incorporated an additional mutation into OLA, increasing its binding affinity and thus transforming it into a super ovine leptin antagonist (SOLA). Second, the Israeli team developed a method whereby polyethylene glycol is covalently attached to SOLA (PEG-SOLA) with the goal of extending its half-life in vivo. The US team used OLA and PEG-SOLA in 2 separate animal models. First, OLA was chronically administered directly into the brain of mature sheep via a cannula implanted into the 3rdcerebroventricule. Unexpectedly, OLA had no effect of voluntary feed intake or various indicators of peripheral insulin action but reduced the plasma concentration of thyroid hormones. Second, the US team tested the effect of peripheral PEG-SOLA administration in an energy sensitive, rapidly growing lamb model. PEG-SOLA was administered for 14 consecutive days after birth or for 5 consecutive days before sacrifice on day 40 of life. Plasma PEG-SOLA had a half-life of over 16 h and circulated in 225- to 288-fold excess over endogenous leptin. PEG-SOLA administration reduced plasma thyroid hormones and resulted in a higher fat content in the carcass at slaughter, but had no effects on feed intake, body weight, plasma glucose or insulin. These results show that the team succeeded in developing a leptin antagonist with a long in vivo half-life. Moreover, in vivo results show that reduced leptin signaling promotes energy sparing in ruminants by repressing thyroid hormone production. Scientific and agricultural implications The physiological role of leptin in ruminants has been difficult to resolve because peripheral administration of wild type leptin causes little effects. Our work with leptin antagonists show for the first time in ruminants that reduced leptin signaling induces energy sparing mechanisms involving thyroid hormone production with little effect on peripheral insulin action. Additional work is needed to develop even more potent leptin antagonists, to establish optimal administration protocols and to narrow down phases of the ruminant life cycle when their use will improve productivity.
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Goetsch, Arthur L., Yoav Aharoni, Arieh Brosh, Ryszard (Richard) Puchala, Terry A. Gipson, Zalman Henkin, Eugene D. Ungar i Amit Dolev. Energy Expenditure for Activity in Free Ranging Ruminants: A Nutritional Frontier. United States Department of Agriculture, czerwiec 2009. http://dx.doi.org/10.32747/2009.7696529.bard.
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Heat production (HP) or energy expenditure for activity (EEa) is of fundamental nutritional importance for livestock because it determines the proportion of ingested nutrients available for productive functions. Previous estimates of EEa are unreliable and vary widely with different indirect methodologies. This leads to erroneous nutritional strategies, especially when intake on pasture does not meet nutritional requirements and supplementation is necessary for acceptable production. Therefore, the objective of this project was to measure EEa in different classes of livestock (beef cattle and goats) over a wide range of ecological and management conditions to develop and evaluate simple means of prediction. In the first study in Israel, small frame (SF) and large frame (LF) cows (268 and 581 kg) were monitored during spring, summer, and autumn. Feed intake by SF cows per unit of metabolic weight was greater (P < 0.001) than that by LF cows in both spring and summer and their apparent selection of higher quality herbage in spring was greater (P < 0.10) than that of LF cows. SF cows grazed more hours per day and walked longer distances than the LF cows during all seasons. The coefficient of specific costs of activities (kJ•kg BW-0.75•d-1) and of locomotion (J•kg BW-0.75•m-1) were smaller for the SF cows. In the second study, cows were monitored in March, May, and September when they grazed relatively large plots, 135 and 78 ha. Energy cost coefficients of standing, grazing, and horizontal locomotion derived were similar to those of the previous study based on data from smaller plots. However, the energy costs of walking idle and of vertical locomotion were greater than those found by Brosh et al. (2006) but similar to those found by Aharoni et al. (2009). In the third study, cows were monitored in February and May in a 78-ha plot with an average slope of 15.5°, whereas average plot slopes of the former studies ranged between 4.3 and 6.9°. Energy cost coefficients of standing, grazing, and walking idle were greater than those calculated in the previous studies. However, the estimated energy costs of locomotion were lower in the steeper plot. A comparison on a similar HP basis, i.e., similar metabolizable energy (ME) intake, shows that the daily energy spent on activities in relation to daily HP increased by 27% as the average plot slope increased from 5.8 and 6.02 to 15.5°. In the fourth study, cows grazing in a woodland habitat were monitored as in previous studies in December, March, and July. Data analysis is in progress. In the first US experiment, Boer and Spanish does with two kids were used in an experiment beginning in late spring at an average of 24 days after kidding. Two does of each breed resided in eight 0.5-ha grass/forb pastures. Periods of 56, 60, 63, 64, and 73 days in length corresponded to mid-lactation, early post-weaning, the late dry period, early gestation, and mid-gestation. EEa expressed as a percentage of the ME requirement for maintenance plus activity in confinement (EEa%) was not influenced by stocking rate, breed, or period, averaging 49%. Behavioral activities (e.g., time spent grazing, walking, and idle, distance traveled) were not highly related to EEa%, although no-intercept regressions against time spent grazing/eating and grazing/eating plus walking indicated an increase in EEa% of 5.8 and 5.1%/h, respectively. In the second study, animal types were yearling Angora doeling goats, yearling Boer wether goats, yearling Spanish wether goats, and Rambouilletwether sheep slightly more than 2 yr of age. Two animals of each type were randomly allocated to one of four pastures 9.3, 12.3, 4.6, and 1.2 ha in area. The experiment was conducted in the summer with three periods, 30, 26, and 26 days in length. EEa% was affected by an interaction between animal type and period (Angora: 16, 17, and 15; Boer: 60, 67, and 34; Spanish: 46, 62, and 42; sheep: 22, 12, and 22% in periods 1, 2, and 3, respectively (SE = 6.1)). EEa% of goats was predicted with moderate accuracy (R2 = 0.40-0.41) and without bias from estimates of 5.8 and 5.1%/h spent grazing/eating and grazing/eating plus walking, respectively, determined in the first experiment; however, these methods were not suitable for sheep. These methods of prediction are simpler and more accurate than currently recommended for goats by the National Research Council.
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Gershon, Eran, i Alan Ealy. Fibroblast growth factor signaling requirements for embryonic and placental development in ruminants. United States Department of Agriculture, styczeń 2016. http://dx.doi.org/10.32747/2016.7600044.bard.
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Provenza, Frederick, Avi Perevolotsky i Nissim Silanikove. Consumption of Tannin-Rich Forage by Ruminants: From Mechanism to Improved Performance. United States Department of Agriculture, kwiecień 2000. http://dx.doi.org/10.32747/2000.7695840.bard.
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Trees and shrubs are potentially important sources of food for livestock in many parts of the world, but their use is limited by tannins. Tannins reduce food intake by decreasing digestibility or by causing illness. Supplementing cattle, sheep, and goats with polyethylene glycol (PEG), which has a high affinity for binding tannins and thus attenuating their aversive effects, increases intake of high-tannin foods and improves weight gains and wool growth. The objectives of this proposal were: Objective 1: To further delineate the conditions under which PEG affects intake of high-tannin foods. Objective 2: To ascertain if animals self-regulate intake of PEG in accord with the tannin content of their diet under pen, paddock, and field conditions. Objective 3: To determine how nutritional status and PEG supplementation affect preference for foods varying in nutrients and tannins. Objective 4: To assess the effects of PEG on food selection, intake, and livestock performance in different production systems. The results from this research show that supplementing livestock with low doses of PEG increases intake of high-tannin foods and improves performance of cattle, sheep, and goats. Neutralizing the effects of tannins with supplemental PEG promotes the use of woody species usually considered useless as forage resources. Supplementing animals with PEG has the potential to improve the profitability - mainly milk production - of high-yielding dairy goats fed high-quality foods and supplemented with browse in Mediterranean areas. However, its contribution to production systems utilizing low-yielding goats is limited. Our findings also support the notion that supplemental PEG enhances the ability of livestock to control shrub encroachment and to maintain firebreaks. However, our work also suggests that the effectiveness of supplemental PEG may be low if alternative forages are equal or superior in nutritional quality and contain fewer metabolites with adverse effects.
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Dahl, Geoffrey E., Sameer Mabjeesh, Thomas B. McFadden i Avi Shamay. Environmental manipulation during the dry period of ruminants: strategies to enhance subsequent lactation. United States Department of Agriculture, luty 2006. http://dx.doi.org/10.32747/2006.7586544.bard.
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The project resulted from earlier observations that environmental factors, especially photoperiod and temperature, had profound effects on milk yield in dairy cattle during lactation. More recently we had determined that photoperiod manipulation during the dry period altered milk yield in the next lactation, and this was associated with shifts in circulating concentrations of prolactin; specifically exposure to short days during the dry period decreases prolactin but increases milk yield. Because prolactin is also affected by temperature, with heat stress causing an increase in prolactin similar to that of long day exposure, we focused our efforts on determining prolactin signaling provides a common pathway for generation of environmental effects on mammary growth, development and subsequent function during the dry period of dairy ruminants. Over the project period we made significant progress toward testing our hypotheses that (I): In cows, there is a discrete duration of time during the dry period in which exposure to short days will result in optimal enhancement of mammary development and milk yield in the following lactation, and that this effect is mediated through demonstrable changes in mammary gland development, prolactin signaling, and mammary gene expression; and (II): Modulation of photoperiod and temperature during the dry period will affect milk yield in goats in the subsequent lactation via shifts in nutrient and endocrine partitioning, and mammary gene expression, during the dry period and into lactation. Cows exposed to short days for only the final 21 days of the dry period did not produce more milk that those on long day or natural photoperiod when dry. However, cows on short days for the entire 60 days dry did produce more milk than the other 3 groups. This indicates that there is a duration effect of short day exposure on subsequent milk yield. Results of the second study in cows indicate that mammary growth increases differentially during the dry period under long vs. short days, and that short days drive more extensive growth which is associated with altered prolactin signaling via decreases in an suppressors of cytokine signaling that represent an inhibitory pathway to mammary growth. Evidence from the studies in Israel confirms that goats respond to short days during the dry period in a similar manner to cows. In addition, heat stress effects on during the dry period can be limited by exposure to short days. Here again, shifts in prolactin signaling, along with changes in IGF-I secretion, are associated with the observed changes in mammary function in goats. These results have a number of biological and practical implications. For dairy producers, it is clear that we can recommend that cows and goats should be on reduced light exposure during the dry period, and further, cows and goats should be cooled to avoid heat stress during that time. Environmental influences on mammary growth are apparent during the dry period, and those effects have persistent impact in the subsequent lactation. Prolactin signaling is a consistent mechanism whereby extended light exposure and heat stress may depress mammary growth and development during the dry period. Thus, the prolactin signaling system offers an opportunity for further manipulation to improve production efficiency in dairy ruminants.
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Polly, Polly, Nancy Bourgeois Lüthi, Li Huachun, Kyaw Naing Oo, Aloun Phonvisay, Sith Premashthira, Ronello Abila, Phillip Widders, Karan Kukreja i Corissa Miller. Movement pathways and market chains of large ruminants in the Greater Mekong Sub-region. O.I.E (World Organisation for Animal Health), styczeń 2015. http://dx.doi.org/10.20506/standz.2782.
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Brosh, Arieh, David Robertshaw, Yoav Aharoni, Zvi Holzer, Mario Gutman i Amichai Arieli. Estimation of Energy Expenditure of Free Living and Growing Domesticated Ruminants by Heart Rate Measurement. United States Department of Agriculture, kwiecień 2002. http://dx.doi.org/10.32747/2002.7580685.bard.
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Research objectives were: 1) To study the effect of diet energy density, level of exercise, thermal conditions and reproductive state on cardiovascular function as it relates to oxygen (O2) mobilization. 2) To validate the use of heart rate (HR) to predict energy expenditure (EE) of ruminants, by measuring and calculating the energy balance components at different productive and reproductive states. 3) To validate the use of HR to identify changes in the metabolizable energy (ME) and ME intake (MEI) of grazing ruminants. Background: The development of an effective method for the measurement of EE is essential for understanding the management of both grazing and confined feedlot animals. The use of HR as a method of estimating EE in free-ranging large ruminants has been limited by the availability of suitable field monitoring equipment and by the absence of empirical understanding of the relationship between cardiac function and metabolic rate. Recent developments in microelectronics provide a good opportunity to use small HR devices to monitor free-range animals. The estimation of O2 uptake (VO2) of animals from their HR has to be based upon a consistent relationship between HR and VO2. The question as to whether, or to what extent, feeding level, environmental conditions and reproductive state affect such a relationship is still unanswered. Studies on the basic physiology of O2 mobilization (in USA) and field and feedlot-based investigations (in Israel) covered a , variety of conditions in order to investigate the possibilities of using HR to estimate EE. In USA the physiological studies conducted using animals with implanted flow probes, show that: I) although stroke volume decreases during intense exercise, VO2 per one heart beat per kgBW0.75 (O2 Pulse, O2P) actually increases and measurement of EE by HR and constant O2P may underestimate VO2unless the slope of the regression relating to heart rate and VO2 is also determined, 2) alterations in VO2 associated with the level of feeding and the effects of feeding itself have no effect on O2P, 3) both pregnancy and lactation may increase blood volume, especially lactation; but they have no effect on O2P, 4) ambient temperature in the range of 15 to 25°C in the resting animal has no effect on O2P, and 5) severe heat stress, induced by exercise, elevates body temperature to a sufficient extent that 14% of cardiac output may be required to dissipate the heat generated by exercise rather than for O2 transport. However, this is an unusual situation and its affect on EE estimation in a freely grazing animal, especially when heart rate is monitored over several days, is minor. In Israel three experiments were carried out in the hot summer to define changes in O2P attributable to changes in the time of day or In the heat load. The animals used were lambs and young calves in the growing phase and highly yielding dairy cows. In the growing animals the time of day, or the heat load, affected HR and VO2, but had no effect on O2P. On the other hand, the O2P measured in lactating cows was affected by the heat load; this is similar to the finding in the USA study of sheep. Energy balance trials were conducted to compare MEI recovery by the retained energy (RE) and by EE as measured by HR and O2P. The trial hypothesis was that if HR reliably estimated EE, the MEI proportion to (EE+RE) would not be significantly different from 1.0. Beef cows along a year of their reproductive cycle and growing lambs were used. The MEI recoveries of both trials were not significantly different from 1.0, 1.062+0.026 and 0.957+0.024 respectively. The cows' reproductive state did not affect the O2P, which is similar to the finding in the USA study. Pasture ME content and animal variables such as HR, VO2, O2P and EE of cows on grazing and in confinement were measured throughout three years under twenty-nine combinations of herbage quality and cows' reproductive state. In twelve grazing states, individual faecal output (FO) was measured and MEI was calculated. Regression analyses of the EE and RE dependent on MEI were highly significant (P<0.001). The predicted values of EE at zero intake (78 kcal/kgBW0.75), were similar to those estimated by NRC (1984). The EE at maintenance condition of the grazing cows (EE=MEI, 125 kcal/kgBW0.75) which are in the range of 96.1 to 125.5 as presented by NRC (1996 pp 6-7) for beef cows. Average daily HR and EE were significantly increased by lactation, P<0.001 and P<0.02 respectively. Grazing ME significantly increased HR and EE, P<0.001 and P<0.00l respectively. In contradiction to the finding in confined ewes and cows, the O2P of the grazing cows was significantly affected by the combined treatments (P<0.00l ); this effect was significantly related to the diet ME (P<0.00l ) and consequently to the MEI (P<0.03). Grazing significantly increased O2P compared to confinement. So, when EE of grazing animals during a certain season of the year is estimated using the HR method, the O2P must be re measured whenever grazing ME changes. A high correlation (R2>0.96) of group average EE and of HR dependency on MEI was also found in confined cows, which were fed six different diets and in growing lambs on three diets. In conclusion, the studies conducted in USA and in Israel investigated in depth the physiological mechanisms of cardiovascular and O2 mobilization, and went on to investigate a wide variety of ruminant species, ages, reproductive states, diets ME, time of intake and time of day, and compared these variables under grazing and confinement conditions. From these combined studies we can conclude that EE can be determined from HR measurements during several days, multiplied by O2P measured over a short period of time (10-15 min). The study showed that RE could be determined during the growing phase without slaughtering. In the near future the development microelectronic devices will enable wide use of the HR method to determine EE and energy balance. It will open new scopes of physiological and agricultural research with minimizes strain on animals. The method also has a high potential as a tool for herd management.