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Letteratura scientifica selezionata sul tema "Cattle Genetics"

Autore: Grafiati

Pubblicato: 4 giugno 2021

Ultima modifica: 20 febbraio 2023

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Articoli di riviste sul tema "Cattle Genetics"

Pirchner, F. "The Genetics of Cattle". Journal of Animal Breeding and Genetics 117, n. 6 (dicembre 2000): 416. http://dx.doi.org/10.1046/j.1439-0388.2000.00259.x.

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Willis, Malcolm B. "The Genetics of Cattle". Heredity 84, n. 1 (gennaio 2000): 131–32. http://dx.doi.org/10.1046/j.1365-2540.2000.0696b.x.

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Edwards, J. H. "The genetics of cattle". Journal of Genetics 80, n. 3 (dicembre 2001): 155–58. http://dx.doi.org/10.1007/bf02717912.

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MacHugh, David E., Mark D. Shriver, Ronan T. Loftus, Patrick Cunningham e Daniel G. Bradley. "Microsatellite DNA Variation and the Evolution, Domestication and Phylogeography of Taurine and Zebu Cattle (Bos taurus and Bos indicus)". Genetics 146, n. 3 (1 luglio 1997): 1071–86. http://dx.doi.org/10.1093/genetics/146.3.1071.

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Genetic variation at 20 microsatellite loci was surveyed to determine the evolutionary relationships and molecular biogeography of 20 different cattle populations from Africa, Europe and Asia. Phylogenetic reconstruction and multivariate analysis highlighted a marked distinction between humpless (taurine) and humped (zebu) cattle, providing strong support for a separate origin for domesticated zebu cattle. A molecular clock calculation using bison (Bison sp.) as an outgroup gave an estimated divergence time between the two subspecies of 610,000-850,000 years. Substantial differences in the distribution of alleles at 10 of these loci were observed between zebu and taurine cattle. These markers subsequently proved very useful for investigations of gene flow and admixture in African populations. When these data were considered in conjunction with previous mitochondrial and Y chromosomal studies, a distinctive male-mediated pattern of zebu genetic introgression was revealed. The introgression of zebu-specific alleles in African cattle afforded a high resolution perspective on the hybrid nature of African cattle populations and also suggested that certain West African populations of valuable disease-tolerant taurine cattle are under threat of genetic absorption by migrating zebu herds.

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Stock, Frauke, e Diane Gifford-Gonzalez. "Genetics and African Cattle Domestication". African Archaeological Review 30, n. 1 (marzo 2013): 51–72. http://dx.doi.org/10.1007/s10437-013-9131-6.

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Bradley, Daniel G., Ronan T. Loftus, Patrick Cunningham e David E. MacHugh. "Genetics and domestic cattle origins". Evolutionary Anthropology: Issues, News, and Reviews 6, n. 3 (1998): 79–86. http://dx.doi.org/10.1002/(sici)1520-6505(1998)6:3<79::aid-evan2>3.0.co;2-r.

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Bishop, M. D., S. M. Kappes, J. W. Keele, R. T. Stone, S. L. Sunden, G. A. Hawkins, S. S. Toldo, R. Fries, M. D. Grosz e J. Yoo. "A genetic linkage map for cattle." Genetics 136, n. 2 (1 febbraio 1994): 619–39. http://dx.doi.org/10.1093/genetics/136.2.619.

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Abstract We report the most extensive physically anchored linkage map for cattle produced to date. Three-hundred thirteen genetic markers ordered in 30 linkage groups, anchored to 24 autosomal chromosomes (n = 29), the X and Y chromosomes, four unanchored syntenic groups and two unassigned linkage groups spanning 2464 cM of the bovine genome are summarized. The map also assigns 19 type I loci to specific chromosomes and/or syntenic groups and four cosmid clones containing informative microsatellites to chromosomes 13, 25 and 29 anchoring syntenic groups U11, U7 and U8, respectively. This map provides the skeletal framework prerequisite to development of a comprehensive genetic map for cattle and analysis of economic trait loci (ETL).

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Mannen, H., S. Tsuji, R. T. Loftus e D. G. Bradley. "Mitochondrial DNA Variation and Evolution of Japanese Black Cattle (Bos taurus)". Genetics 150, n. 3 (1 novembre 1998): 1169–75. http://dx.doi.org/10.1093/genetics/150.3.1169.

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Abstract This article describes complete mitochondrial DNA displacement loop sequences from 32 Japanese Black cattle and the analysis of these data in conjunction with previously published sequences from African, European, and Indian subjects. The origins of North East Asian domesticated cattle are unclear. The earliest domestic cattle in the region were Bos taurus and may have been domesticated from local wild cattle (aurochsen; B. primigenius), or perhaps had an origin in migrants from the early domestic center of the Near East. In phylogenetic analyses, taurine sequences form a dense tree with a center consisting of intermingled European and Japanese sequences with one group of Japanese and another of all African sequences, each forming distinct clusters at extremes of the phylogeny. This topology and calibrated levels of sequence divergence suggest that the clusters may represent three different strains of ancestral aurochs, adopted at geographically and temporally separate stages of the domestication process. Unlike Africa, half of Japanese cattle sequences are topologically intermingled with the European variants. This suggests an interchange of variants that may be ancient, perhaps a legacy of the first introduction of domesticates to East Asia.

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Crow, J. F. "Erwin Schrödinger and the hornless cattle problem." Genetics 130, n. 2 (1 febbraio 1992): 237–39. http://dx.doi.org/10.1093/genetics/130.2.237.

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Vermeersch, A., e G. Opsomer. "Digital dermatitis in cattle". Vlaams Diergeneeskundig Tijdschrift 88, n. 5 (31 ottobre 2019): 247–58. http://dx.doi.org/10.21825/vdt.v88i5.15996.

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Digital dermatitis or Mortellaro’s disease is a highly prevalent bovine dermatological disorder situated in the foot region that causes lameness and impairs animal welfare. In this first part of a twin paper, the role of genetics, immunity, bacteria and hygiene in the development of this complex disease are described. There is still no consensus regarding the role of the immune system and the typically isolated Treponema spp. in the pathogenesis of digital dermatitis. Moisture and dirt are undoubtedly important for disease transmission in and between dairy farms; furthermore, the genetic component of the disease will be more deeply discussed.

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Più fonti

Tesi sul tema "Cattle Genetics"

Wang, Wei. "Plasminogen polymorphism in dairy cattle". Thesis, McGill University, 1994. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=26174.

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A genetic approach to lowering protease (plasmin) levels in milk, requires the presence of polymorphism of bovine plasminogen. This study was conducted to determine to what extent genetic polymorphism exists in dairy cattle. Bovine plasminogen was first purified from Holstein cow plasma by affinity chromatography on Lysine-Sepharose and antibodies to bovine plasminogen were raised by monthly intramuscular injection of the isolated bovine plasminogen into rabbits. For plasminogen phenotyping, blood samples were collected at random from 50 Holstein and Ayrshire cattle, and plasminogen was isolated from the plasma using lysine-Sepharose and then treated with neuraminidase. After separation by isoelectric focusing (pH 3.5-9.5) in polyacrylamide gels, Plasminogen polymorphs were detected immunologically using rabbit anti-bovine plasminogen antibodies. Additionally, the plasminogen isoforms were evaluated with a functional assay (caseinolytic overlay technique) after activation of the plasminogen with urokinase. Six plasminogen phenotypes were identified which represent products of 5 variant alleles. The 5 plasminogen variants were characterized based on their isoelectric points and designated PLG A$ sb2$ (pI 6.5 and 7.0), B$ sb2$ (pI 7.6 and 7.8), C$ sb1$ (pI 6.8), D$ sb2$ (pI 7.8 and 8.0), and E$ sb2$ (pI 6.8 and 7.0). PLG A$ sb2$ and PLG B$ sb2$ were the most common variants in these cattle. The 6 phenotypes were $ rm A sb2A sb2, B sb2B sb2, A sb2B sb2, B sb2C sb1, A sb2D sb2 and D sb2E sb2$. The phenotypic frequencies in Holstein and Ayrshire were very different, $ rm A sb2A sb2 and B sb2B sb2$ being respectively the most frequent phenotype. In addition, DNA polymorphism at bovine plasminogen gene was detected when genomic DNA was digested with the restriction enzyme Msp I and hybridized with mouse plasminogen cDNA. This is the first description of plasminogen polymorphism reported in dairy cattle. If different variants have altered activity, the detrimental effect

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Afolayan, Raphael Abiodun. "Genetics of growth and development in cattle". Title page, table of contents and abstract only, 2003. http://web4.library.adelaide.edu.au/theses/09PH/09pha2579.pdf.

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Pryce, Jennie Elizabeth. "Genetics of health and fertility in dairy cattle". Thesis, University of Edinburgh, 1997. http://hdl.handle.net/1842/23523.

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In this study genetic parameters were estimated and the importance of genotype by feeding system interactions investigated for a range of health and fertility traits in dairy cattle. Data were from the Langhill Dairy Cattle Research Centre and two UK recording schemes, one a recording scheme operated by the Scottish Livestock Services Ltd. (SLS) and the other a health and fertility recording and management system, the Dairy Information System (DAISY). Genetic parameters for 305 day yield of milk and its components, health traits (mastitis, somatic cell counts (SCC), lameness and milk fever) and fertility traits (calving interval, days to first service and conception to first service) were estimated using data from DAISY and SLS. Heritabilities and correlations agreed well between the two data sets implying that the nature of the recording scheme had little effect on the parameter estimates obtained. Heritabilities for all health and fertility traits were less than 0.10 with the exception of SCC which had a heritability of 0.15. The genetic correlation between SCC and mastitis was estimated to be 0.65. Genetic correlations of health and fertility traits with production were in all cases unfavourable. Using these estimates, a breeding programme designed to maximise response in production was predicted to increase calving intervals, mastitis and lameness by 0.39, 0.27 and 0.13 genetic standard deviations per unit selection differential. Restricting these traits to zero genetic change was predicted to result in 11% less overall economic response in production than an unrestricted index. Genotype by feeding system interactions were investigated for a wider range of health and fertility traits using data from Langhill. Selection and control line animals housed and managed as one herd were assigned to either a high concentrate or low concentrate feeding system. There were no significant genetic line by feeding system interactions. However, regressions of the traits on pedigree index for fat plus protein yield (PI) were significantly different from zero for six measures of fertility and mastitis. It was concluded that selection for production has led to a deterioration in some health and fertility traits in UK dairy herds. This deterioration could be halted, or the situation improved by direct recording and selection. However, in the absence of a national recording scheme for health and fertility, an alternative would be to use predictor traits, as they are generally easier to measure and record and have higher heritabilities. Results from this study supports the use of SCC as a selection criterion for mastitis (on a small data set), but the regressions on sire predicted transmitting abilities for type were less conclusive. Therefore future research should investigate associations between health, fertility, production, type, SCC and other potential predictor traits more fully and compare the role of direct measurements of these traits or indirect predictions of them in national indices.

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Obike, Onyemauchechi Mercy. "Genetics of health and lameness in dairy cattle". Thesis, University of Edinburgh, 2009. http://hdl.handle.net/1842/4113.

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For the modern dairy cow, advances in genetics and breeding for productivity has resulted in an increasing incidence of health disorders and reduced longevity. One of the most important health problems is lameness, which has led to significant economic, production and welfare consequences. A reduction in lameness will improve the economic future of the dairy industry through increased profitability and decreased welfare-related problems. Although positive attempts have been made by researchers and the industry towards improving lameness, it has remained a persistent ailment for dairy farmers. Further analysis of the genetic and environmental factors influencing lameness is warranted so that selection indices and management practices can be modified leading to improved health and welfare of the dairy cow. Several factors that cause dairy cow lameness have been implicated. I reviewed previous studies on these causative factors as well as the association between lameness, longevity and fertility. It has also been suggested that lameness affects milk production of dairy cows, but reports on the association between lameness and daily milk yield of cows have varied among researchers. Using locomotion score data on 248 cows from the Langhill herd, I investigated the relationship between locomotion score which has a high genetic correlation with lameness and various explanatory variables and also the association between daily milk yield and lameness. The study revealed that the most significant factors affecting locomotion are management regime (high concentrate feed and all year indoor housing; low concentrate feed and outdoors in summer) and time of year when cows are locomotion scored. It also showed that lameness adversely affects the milk yield of later lactation cows, and that high yielding cows are more susceptible to lameness. Housing environment plays a significant role in the health and welfare of dairy cows. With national type evaluation records, I estimated the association between housing systems and lameness-related type traits as well as genetic parameters for the locomotion traits. The analysis indicated that cows kept at pasture had favourable linear and composite type trait scores compared with cows in cubicles, straw yards and slatted floors or loafing yards. Locomotion score had strong genetic and phenotypic correlations with the leg and feet composite. Bone quality, which is a new trait in the UK type classification scheme, was moderately heritable (0.23) and had a moderate and positive genetic association with locomotion and leg and feet composite. This suggests that breeding for flatter, more refined bones could reduce locomotion disorders and help improve the longevity of the dairy cow. Analysis of national data again showed reduced incidence of digital dermatitis (DD) for cows at pasture and those with flatter, more refined bones, higher locomotion score and better leg and feet composite. Estimates of genetic parameters indicated heritable variation of DD among cows and moderate genetic associations between DD and production traits and longevity. Incorporating DD in future selection indices will be useful for increased productive life. Using random regression, I analysed changes in type traits associated with lameness (locomotion, rear legs, side view, foot angle and leg and feet composite) in relation to time (months) that cows had spent in cubicles before being classified. The general trend supported the fact that cubicle housing is unfavourable to these traits. There was significant evidence of a genotype x environment interaction, suggesting variation between bulls in the sensitivity of their daughters to cubicle housing with time.

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Guarini, Aline Rocha [UNESP]. "Genetic relationship between reproductive traits in Nellore cattle". Universidade Estadual Paulista (UNESP), 2013. http://hdl.handle.net/11449/92557.

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The aim of this study was to estimate genetic parameters between scrotal circumference obtained at 18 months of age (SC) and reproductive traits measured directly in Nellore females, such as number of calvings at 53 months (NC53), heifers rebreeding (HR) and stayability (STAY) in order to investigate the possibility of using traits measured directly in females as a selection criteria in cattle breeding programs, besides, studying and evaluating if number of calvings at 53 months could be used as an alternative way for measuring longevity in cattle herds. Two methods were applied for estimating variance components in order to predict breeding values: restricted maximum likelihood (REML) and Bayesian inference. The average estimates of heritability by bivariate model using REML were equal to 0.013 ± 0.003, 0.057 ± 0.007, 0.039 ± 0.007 and 0.530 ± 0.013 for NC53, STAY, HR and SC, respectively. Using the Bayesian method, the estimates were 0.22 ± 0.009, 0.19 ± 0.025, 0.15 ± 0.021 and 0.52 ± 0.019 for NC53, STAY, HR and SC, respectively. Based on the correlations between reproductive traits measured in females, the selection of animals for NC53 will cause anticipation on genetic evaluation of bulls for longevity, based on the performance of their daughters, from 76 to 53 months

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Ali, Abdirahman. "Quantitative genetics and genomics of production and disease in beef cattle". Thesis, The University of Sydney, 2013. http://hdl.handle.net/2123/12296.

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Cattle grazing in extensive open pasture of tropical areas are subjected to several environmental stressors such as heat and humidity, high incidence of disease, cattle ticks and worm infestations. These stressors have major impacts on productivity and animal welfare. The overall focus of this PhD thesis was to conduct classical genetic and modern quantitative genomics analyses for growth and carcass related traits, and disease and parasite tolerance/resistance traits in beef cattle. The specific objectives were: (1) to estimate genetic parameters for growth, carcass related traits, and tropical environment stressors, e.g., infectious bovine keratoconjunctivitis or “pinkeye”, cattle tick counts, and helminth or worm egg counts in Australian tropical adapted beef cattle; (2) to identify genetic markers or gene(s) linked to growth and ultrasound measures of carcass related traits in tropical Australian cattle, and bovine tuberculosis (BTB) traits in African zebu cattle using a genome-wide scan methodology; and (3) to evaluate the feasibility of genome-wide epistasis association for growth and carcass related traits using a two-step two-locus model for Australian tropical beef cattle. Field test data obtained from different sources were used in this thesis. Genetic parameter estimates were computed using mixed models by fitting an additive polygenic animal term as a random effect, whereas in genome association analyses, the genetic markers were fitted as fixed effect and significance of marker effects on the traits were evaluated for association. The heritabilities of tropical stressors traits ranged from low to moderate, suggesting genetic selection is feasible, though the selection response will be slow in this resource population. There was no evidence of unfavourable genetic correlations between environment stressors and growth traits; hence selection against environmental stressors would not have a detrimental effect on production performance. A genome-wide scan identified seven SNP markers on chromosome 14 associated with serum concentration of insulin-like growth factor-1, subcutaneous fat depth, and body condition score measured in Australian Brahman cattle. The rs29020688 marker located in the intronic region of Bos taurus XK, Kell blood group complex subunit-related family, member 4 (XKR4) gene was strongly associated with increased blood levels of insulin-like growth factor-1 (IGF-1), and rs29010471 marker located in the intronic of Bos taurus protein kinase, DNA-activated, catalytic polypeptide (PRKDC) gene was strongly associated with subcutaneous fat deposits. These positional genes could be candidate genes influencing IGF-1 and subcutaneous fat depth, and can potentially be used as biomarkers for these traits. Similarly, this thesis investigated associations between SLC11A1 candidate gene and a panel of microsatellite markers and several diagnostic tests of bovine tuberculosis (BTB) phenotypes. Polymorphisms at SLC11A1 alleles 211, 215 and 217 and alleles in ILSTS006 (Alleles: 286, 288, 290, and 292) and BM2113 (Alleles: 133 and 141) were significantly associated with decreased BTB disease incidence in African zebu cattle; hence these could be considered in a marker assisted selection for screening BTB tolerant animals. This study was able to successfully model epistasis interactions between two-SNP loci using two-step approach. Using experimental field data, it was demonstrated and validated that two-step two-locus epistatic interactions are computationally feasible at a genome-wide scale. If automated recording technology for extensive gazing beef cattle becomes available in the future, this will enable the collection of high dimensional data on animals. In addition large number of animals are expected to be genotyped and imputed up to very high marker densities using imputation techniques. These resources will enable the estimation of genetic parameters more accurately and will allow biomarkers and genes underlying many complex traits in animals in extensive grazing system to be identified.

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Brown, Pamela. "Cloning and characterisation of MHC class 1 genes in cattle". Thesis, University of Edinburgh, 1990. http://hdl.handle.net/1842/30048.

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Sirol, Mirella Leme Franco Geraldini [UNESP]. "Análise da heterogeneidade de variância em características de crescimeno de bovinos da raça nelore". Universidade Estadual Paulista (UNESP), 2007. http://hdl.handle.net/11449/104056.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
Universidade Estadual Paulista (UNESP)
Foram utilizados dados de 116406 bovinos da raça Nelore, participantes do Programa de Melhoramento Genético da Raça Nelore (PMGRN), nascidos entre 1995 e 2005, com o objetivo de estimar parâmetros genéticos para os pesos padronizados aos 120(P120), 210(P210), 365(P365), 450(P450) e 730(P730) dias de idade e para os ganhos em peso do nascimento aos 120(GP120), dos 120 aos 210 (GP210), dos 210 aos 365(GP365), dos 365 aos 450(GP450) e dos 450 aos 730(G730), além de avaliar a tendência genética das características citadas, tanto para efeito direto como materno. Os componentes de variância foram estimados pelo método de máxima verossimilhança restrita utilizando o programa AIREMLF90, sob modelo animal, o qual incluiu como efeitos fixos, os grupos de contemporâneos e idade da vaca ao parto e como aleatórios, efeito genético aditivo direto para todas as características estudadas e efeito genético materno para P120, P210, P365, GP120, GP210 e GP365. As estimativas de herdabilidade direta foram 0,21, 0,22, 0,22, 0,34, 0,28, para cada peso, respectivamente, e 0,19, 0,20, 0,18, 0,18 e 0,20, para os respectivos ganhos em peso. As herdabilidades maternas foram 0,26, 0,25 e 0,12, para P120, P210 e P365 e 0,23, 0,17, 0,12 para GP120, GP210 e GP365. As correlações direto-maternas foram todas negativas, exceto para P365 (0,06). As tendências genéticas diretas foram todas positivas. As tendências maternas foram quase nulas para todas as características. As estimativas de herdabilidade para os pesos padronizados e para os ganhos em peso indicam que a seleção pode promover mudanças genéticas. As herdabilidades maternas para P120, P210, P365 e GP365 indicam que a seleção nestas características pode contribuir para melhorar a habilidade materna do rebanho. Os ganhos genéticos diretos observados, para todas as características estão aquém dos ganhos potenciais da raça Nelore...
Data of 116406 bovines of the Nellore beef cattle, participants of the Programa de Melhoramento Genético da Raça Nelore (PMGRN), been born between 1995 and 2005 were used with the objective to estimate genetic parameters for the 120-days weight (P120), 210-days weight (P210), 365-days weight (P365), 450-days weight (P450) and 730-days weight (P730) and for the weight gain from birth to 120(GP120), from 120 to 210(GP210), from 210 to 365(GP365), from 365 to 450(GP450) and from 450 to 730 days weight(GP730), besides evaluating the genetic trends of the traits, so much for the direct effect as for the maternal. The variance components were estimated by the restricted maximum likelihood method using the program AIREMLF90. The animal model included fixed effects for contemporary groups and age of the dam at calving, and also included random effects for genetic direct effects for all the studied traits and genetic maternal effect for P120, P210, P365, GP120, GP210 and GP365. The estimative of direct heritability were 0,21, 0,22, 0,22, 0,34, 0,28, for each weight, respectively and 0,19, 0,20, 0,18, 0,18 and 0,20, for the respective weight gains. The maternal heritability were 0,26, 0,25 and 0,12, for P120, P210 and P365 and 0,23, 0,17, 0,12 for GP120, GP210 and GP365. The direct-maternal correlations were all negatives except for P365 (0,06). The direct genetic trends were all positive ones. The maternal trends were almost null for all the traits. The estimative of heritability for the adjusted weights and for the weight gains indicated that the selection could promote genetic changes. The maternal heritability for P120, P210, P365 and GP365 indicated that the selection in these traits could contribute to improve the maternal ability of the herd. The direct genetic gain observed, for all the traits were on this side of the potential gain of the Nellore beef cattle... (Complete abstract click electronic access below)

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Brotherstone, Susan H. "Genetics of production, type and herd life in dairy cattle". Thesis, University of Edinburgh, 1994. http://hdl.handle.net/1842/12813.

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The main objective of this work was to undertake analyses which would lead to an improvement in the accuracy of production and type breeding value predictions for Holstein-Friesian dairy cattle and to investigate the relationship between production and type traits and herd life. Production records were obtained from the National Milk Records files and linear type records from the Holstein Friesian Society. An animal model estimation of heterosis and recombination loss between North American Holstein and European cattle for first lactation milk, fat and protein yield showed that the omission of these effects in breeding value prediction would bias the results. Including both these effects in the breeding value estimation increased the predicated sire proof for fat plus protein yield of a typical F1 Holstein X Friessian sire by 3kg. An analysis of approximately 275 000 first lactation records and the 2^nd to 5^th lactation records of survivors found the regression coefficients of yield in lactations 1 to 5 on heterosis and recombination loss to be fairly consistent over lactations. After fitting first lactation yield in the model and compared to a pure Friesian, there is an increased chance of survival to third lactation of 3.6% for a pure Holstein, 3.8% for an F1 and an F2, and 2.4% for a Friesian backcross. In the investigation of herd life, defined as the completion of a specified number of lactations, in relation to linear type traits and production, results were not completely consistent either over lactations or over different subsets of the population. In general, there was a significant positive association between survival and angularity, fore udder attachment and udder depth and a negative association with chest width, rump width and teat length. Regressions on yield were positive, while those on fat and protein content were usually negative.

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Budeli, Mutshinya Ananias. "Genetics evaluation of tick resistance in South African Bonsmara cattle". Thesis, University of Limpopo (Turfloop Campus), 2010. http://hdl.handle.net/10386/883.

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Thesis (M.Sc. (Agric.)) --University of Limpopo, 2010
The objectives of the study were to estimate genetic parameters for tick resistance and to evaluate the effect of the level of tick infestation on the estimates of genetic parameters in South African Bonsmara cattle. Field data of repeated tick count records (n = 11 280) on 1 176 animals were collected between 1993 and 2005 by ten breeders participating in the National Beef Recording and Improvement Scheme. The distribution of tick count records were normalized using a Box-Cox transformation. Data were divided into 7 sub-data sets based on the mean tick count per contemporary group, to facilitate the investigation of the effect of level of tick infestation on the derived genetic parameters. A repeatability animal model including the fixed effects of contemporary group and age of animal at tick counting and random effects of the direct additive genetic, permanent environmental and residual effects was used to estimate genetic parameters using REML procedures. The additive genetic variances for tick count ranged from 0.01 to 0.08. Variances for the permanent environment ranged from 0.00 to 0.03. Phenotypic variance decreased with increasing mean tick count level while additive genetic variance increased with increasing mean tick count level. The heritability also increased with mean tick count level until a mean tick count level of ≥30. The highest heritability estimate obtained in the current study was 0.17 for data with mean tick count level ≥25. These results suggest that sufficient genetic variation for tick count exists in the Bonsmara cattle. Therefore genetic selection for tick resistance is feasible even though genetic progress may be slow.
the Limpopo Department of Agriculture (LDA) and the Department of Science and Technology (DST)

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Più fonti

Libri sul tema "Cattle Genetics"

Garrick, D. J., e A. Ruvinsky, a cura di. The genetics of cattle. Wallingford: CABI, 2015. http://dx.doi.org/10.1079/9781780642215.0000.

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1933-, Millar P., Lauvergne J. J e Dolling, C. H. S. 1925-, a cura di. Mendelian inheritance in cattle 2000. Wangeningen: Wageningen Pers, 2000.

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EAAP-Seminar, Study Commissions on Cattle Production and Animal Genetics (1988 Kiel Germany). New selection schemes in cattle: Nucleus programmes : proceedings of the EAAP-Seminar Study Commissions on Cattle Production and Animal Genetics, Kiel, Federal Republic of Germany, 1-2 December, 1988. Wageningen: Pudoc, 1989.

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Zavala, Daniel A. F. Villagomez. Synaptonemal complex analysis of chromosome translocations in pigs and cattle. Uppsala: Sveriges Lantbruksuniversitet, 1993.

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V, Stepani͡u︡k E., e Zakharov I. A, a cura di. Ot͡s︡enka sily st͡s︡eplenii͡a︡ genov maloplodnykh selʹskokhozi͡a︡ĭstvennykh zhivotnykh na osnove populi͡a︡t͡s︡ionno-genealogicheskikh dannykh. Syktyvkar: Akademii͡a︡ nauk SSSR, Komi filial, In-t biologii, 1987.

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Womack, James E. Bovine genomics. Ames, Iowa: Wiley-Blackwell, 2012.

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Bovine genomics. Ames, Iowa: Wiley-Blackwell, 2012.

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Verschoor, Chris P. Unraveling the genetics of bovine Johne's disease. Hauppauge, N.Y: Nova Science Publishers, 2010.

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Sigurðardʹottir, Sunna. Studies of the class II genes of the major histocompatibility complex in cattle. Uppsala: Swedish University of Agricultural Sciences, Dept. of Animal Breeding and Genetics, 1991.

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Quinn, Katherine. The genetic evaluation of calving ease and related traits in Ireland. Dublin: University College Dublin, 1998.

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Capitoli di libri sul tema "Cattle Genetics"

Rege, J. E. O., Joel Ochieng e Olivier Hanotte. "Livestock genetics and breeding." In The impact of the International Livestock Research Institute, 59–102. Wallingford: CABI, 2020. http://dx.doi.org/10.1079/9781789241853.0059.

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Abstract This chapter describes the contributions of the International Livestock Research Institute's (ILRI) to animal breeding. The specific topics include the genetic characterization and history of livestock, breeding technologies, genetic improvement of indigenous livestock, tools and methods for conducting breed surveys, classification of African livestock populations, molecular genetic characterization, the genetic history of cattle in Africa and linking livestock to human history, genetic history and geography of African sheep, genetic history and geography of African chickens, genetic history and geography of the African dromedary, establishment of a joint laboratory with CAAS in Beijing and expansion into Asia, ILRI's genetic characterization as a catalyst for international interest, genetics of trypanotolerance and genetics of resistance to gastrointestinal parasites.

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Schmutz, Sheila M. "Genetics of Coat Color in Cattle". In Bovine Genomics, 20–33. Oxford, UK: Wiley-Blackwell, 2012. http://dx.doi.org/10.1002/9781118301739.ch3.

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Simm, Geoff, Geoff Pollott, Raphael Mrode, Ross Houston e Karen Marshall. "Beef cattle breeding." In Genetic improvement of farmed animals, 292–318. Wallingford: CABI, 2021. http://dx.doi.org/10.1079/9781789241723.0292.

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Abstract This chapter highlights the application of genetic principles such as strategies for genetic improvements, selection response within breeds, tools and technologies in animal breeding, genetic analysis, and predicting values in beef cattle.

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Simm, Geoff, Geoff Pollott, Raphael Mrode, Ross Houston e Karen Marshall. "Dairy cattle breeding." In Genetic improvement of farmed animals, 234–91. Wallingford: CABI, 2021. http://dx.doi.org/10.1079/9781789241723.0234.

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Abstract This chapter discussed the effects of applying the different principles in animal breeding such genetic analysis, predicting breeding values, use of tools and breeding technology, selection response within breeds, and strategies for genetic improvements in dairy cattle.

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Daigle, Courtney, Andy D. Herring e Fuller W. Bazer. "Breeding and Welfare: Genetic Manipulation of Beef and Dairy Cattle". In The Welfare of Cattle, 93–108. Boca Raton : Taylor & Francis, 2018.: CRC Press, 2018. http://dx.doi.org/10.1201/b21911-11.

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Singh Kuntal, Ravinder, Radha Gupta, D. Rajendran e Vishal Patil. "Binary Coded Genetic Algorithm to Solve Ration Formulation Problem". In Livestock Ration Formulation for Dairy Cattle and Buffalo, 27–43. Boca Raton: CRC Press, 2022. http://dx.doi.org/10.1201/9781003231714-4.

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Schutz, M. M., V. Maciuc, K. Gay e T. Nennich. "18. Survey of genetic selection on pasture-based dairy farms in the USA and Romania". In Cattle husbandry in Eastern Europe and China, 223–30. The Netherlands: Wageningen Academic Publishers, 2014. http://dx.doi.org/10.3920/978-90-8686-785-1_18.

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Simm, Geoff, Geoff Pollott, Raphael Mrode, Ross Houston e Karen Marshall. "The origins and rôles of today's livestock breeds." In Genetic improvement of farmed animals, 1–10. Wallingford: CABI, 2021. http://dx.doi.org/10.1079/9781789241723.0001.

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Abstract The huge variety of animal and other species that we see today, together with those now extinct, evolved by the process of natural selection. The key to natural selection, and to the artificial selection practised by breeders, is the inherited variation in many characteristics that exists between individual animals. Domestication of animals began 12,000 to 10,000 years ago. Whether or not it has been done knowingly, artificial selection, as well as natural selection, has been practised among domestic animals ever since then. Although distinct breeds or strains of cattle and sheep existed long before then, the practices of pedigree recording and selection of related animals with the aim of breed improvement date from the mid-1700s. The formation of herd books began early in the following century. Livestock continue to have a wide range of important rôles globally, with a range of positive and negative societal and environmental impacts, which need to be managed and balanced.

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Singh Kuntal, Ravinder, Radha Gupta, D. Rajendran e Vishal Patil. "Least Cost Feed Formulation for Dairy Cattle during Pregnancy by Using Real Coded Genetic Algorithm". In Livestock Ration Formulation for Dairy Cattle and Buffalo, 45–68. Boca Raton: CRC Press, 2022. http://dx.doi.org/10.1201/9781003231714-5.

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Kasarda, Radovan, e Nina Moravčíková. "Genetic Uniqueness of Local Cattle Populations as Part of Homeland Heritage". In Environmental History, 127–45. Cham: Springer International Publishing, 2021. http://dx.doi.org/10.1007/978-3-030-58092-6_9.

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Atti di convegni sul tema "Cattle Genetics"

Neumann, G. B., P. Korkuć, P. Arends, M. J. Wolf, K. May, S. König e G. A. Brockmann. "238. Phylogenetic analysis and nucleotide diversity of 69 cattle breeds including German Black Pied cattle using WGS". In World Congress on Genetics Applied to Livestock Production. The Netherlands: Wageningen Academic Publishers, 2022. http://dx.doi.org/10.3920/978-90-8686-940-4_238.

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Talenti, A., J. Powell, D. Wragg, E. Paxton, M. Chepkwony, A. Miyunga, R. Njeru et al. "417. Expanding the cattle reference graph genome". In World Congress on Genetics Applied to Livestock Production. The Netherlands: Wageningen Academic Publishers, 2022. http://dx.doi.org/10.3920/978-90-8686-940-4_417.

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Rönnegård, L., I. Hansson e W. F. Fikse. "109. Heritability of social interactions in dairy cattle". In World Congress on Genetics Applied to Livestock Production. The Netherlands: Wageningen Academic Publishers, 2022. http://dx.doi.org/10.3920/978-90-8686-940-4_109.

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T.M. Brown-Brandl, J.A. Nienaber, R.A. Eigenberg, T.L. Mader, J.L. Morrow e J.W. Dailey. "Relative Heat Tolerance Among Cattle of Different Genetics". In 2003, Las Vegas, NV July 27-30, 2003. St. Joseph, MI: American Society of Agricultural and Biological Engineers, 2003. http://dx.doi.org/10.13031/2013.14093.

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Hay, E., S. Toghiani, A. J. Roberts, T. Paim, L. A. Kuehn e H. D. Blackburn. "193. Genetic architecture of a composite beef cattle population". In World Congress on Genetics Applied to Livestock Production. The Netherlands: Wageningen Academic Publishers, 2022. http://dx.doi.org/10.3920/978-90-8686-940-4_193.

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Lu, D., A. Garcia, S. Miller e K. Retallick. "368. Haplotypes affecting pulmonary arterial pressure in Angus cattle". In World Congress on Genetics Applied to Livestock Production. The Netherlands: Wageningen Academic Publishers, 2022. http://dx.doi.org/10.3920/978-90-8686-940-4_368.

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Oget-Ebrad, C., G. C. M. Moreira, L. Karim, W. Coppieters, C. Charlier, M. Georges e T. Druet. "201. Fine-scale study of meiotic recombination in cattle". In World Congress on Genetics Applied to Livestock Production. The Netherlands: Wageningen Academic Publishers, 2022. http://dx.doi.org/10.3920/978-90-8686-940-4_201.

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Januarie, D. A., E. D. Cason e F. W. C. Neser. "219. Genetic characterization of the indigenous Sanga cattle of Namibia". In World Congress on Genetics Applied to Livestock Production. The Netherlands: Wageningen Academic Publishers, 2022. http://dx.doi.org/10.3920/978-90-8686-940-4_219.

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Segelke, D., H. Alkhoder e J. Wabbersen. "134. Image-based cattle conformation prediction using deep learning methods". In World Congress on Genetics Applied to Livestock Production. The Netherlands: Wageningen Academic Publishers, 2022. http://dx.doi.org/10.3920/978-90-8686-940-4_134.

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Soma, P., B. B. Kooverjee e M. M. Scholtz. "223. Runs of homozygosity in Nguni and Bonsmara cattle populations". In World Congress on Genetics Applied to Livestock Production. The Netherlands: Wageningen Academic Publishers, 2022. http://dx.doi.org/10.3920/978-90-8686-940-4_223.

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Rapporti di organizzazioni sul tema "Cattle Genetics"

Mishra, Bishnu P., Julie A. L. Cavanagh e James M. Reecy. Identifying genetic cause of Dwarfism in American Angus cattle. Ames (Iowa): Iowa State University, gennaio 2004. http://dx.doi.org/10.31274/ans_air-180814-407.

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Garrick, Dorian J., Rohan L. Fernando, Kadir Kizilkaya e James M. Reecy. High-Density SNP Genotypes for Predicting Genetic Merit of Beef Cattle. Ames (Iowa): Iowa State University, gennaio 2009. http://dx.doi.org/10.31274/ans_air-180814-506.

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Sun, Xiaochen, Hailin Su e Dorian J. Garrick. Genetic Difference of Five Beef Cattle Breeds Characterized by Genome-wide SNPs and Haplotypes. Ames (Iowa): Iowa State University, gennaio 2016. http://dx.doi.org/10.31274/ans_air-180814-498.

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Tait, Richard G., Shu Zhang, Travis Knight, Daryl R. Strohbehn, Donald C. Beitz e James M. Reecy. Genetic Correlations of Fatty Acid Concentrations with Carcass Traits in Angus-Sired Beef Cattle. Ames (Iowa): Iowa State University, gennaio 2008. http://dx.doi.org/10.31274/ans_air-180814-501.

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Su, Hailin, Dorian J. Garrick, Bruce Golden e Lauren Hyde. Estimation of Genetic Parameters for Carcass Traits and Their Corresponding Ultrasound Measurements in Crossbred Beef Cattle. Ames (Iowa): Iowa State University, gennaio 2016. http://dx.doi.org/10.31274/ans_air-180814-486.

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Brosh, Arieh, Gordon Carstens, Kristen Johnson, Ariel Shabtay, Joshuah Miron, Yoav Aharoni, Luis Tedeschi e Ilan Halachmi. Enhancing Sustainability of Cattle Production Systems through Discovery of Biomarkers for Feed Efficiency. United States Department of Agriculture, luglio 2011. http://dx.doi.org/10.32747/2011.7592644.bard.

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Feed inputs represent the largest variable cost of producing meat and milk from ruminant animals. Thus, strategies that improve the efficiency of feed utilization are needed to improve the global competitiveness of Israeli and U.S. cattle industries, and mitigate their environmental impact through reductions in nutrient excretions and greenhouse gas emissions. Implementation of innovative technologies that will enhance genetic merit for feed efficiency is arguably one of the most cost-effective strategies to meet future demands for animal-protein foods in an environmentally sustainable manner. While considerable genetic variation in feed efficiency exist within cattle populations, the expense of measuring individual-animal feed intake has precluded implementation of selection programs that target this trait. Residual feed intake (RFI) is a trait that quantifies between-animal variation in feed intake beyond that expected to meet energy requirements for maintenance and production, with efficient animals being those that eat less than expected for a given size and level of production. There remains a critical need to understand the biological drivers for genetic variation in RFI to facilitate development of effective selection programs in the future. Therefore, the aim of this project was to determine the biological basis for phenotypic variation in RFI of growing and lactating cattle, and discover metabolic biomarkers of RFI for early and more cost-effective selection of cattle for feed efficiency. Objectives were to: (1) Characterize the phenotypic relationships between RFI and production traits (growth or lactation), (2) Quantify inter-animal variation in residual HP, (3) Determine if divergent RFIphenotypes differ in HP, residual HP, recovered energy and digestibility, and (4) Determine if divergent RFI phenotypes differ in physical activity, feeding behavior traits, serum hormones and metabolites and hepatic mitochondrial traits. The major research findings from this project to date include: In lactating dairy cattle, substantial phenotypic variation in RFI was demonstrated as cows classified as having low RMEI consumed 17% less MEI than high-RMEI cows despite having similar body size and lactation productivity. Further, between-animal variation in RMEI was found to moderately associated with differences in RHP demonstrating that maintenance energy requirements contribute to observed differences in RFI. Quantifying energetic efficiency of dairy cows using RHP revealed that substantial changes occur as week of lactation advances—thus it will be critical to measure RMEI at a standardized stage of lactation. Finally, to determine RMEI in lactating dairy cows, individual DMI and production data should be collected for a minimum of 6 wk. We demonstrated that a favorably association exists between RFI in growing heifers and efficiency of forage utilization in pregnant cows. Therefore, results indicate that female progeny from parents selected for low RFI during postweaning development will also be efficient as mature females, which has positive implications for both dairy and beef cattle industries. Results from the beef cattle studies further extend our knowledge regarding the biological drivers of phenotypic variation in RFI of growing animals, and demonstrate that significant differences in feeding behavioral patterns, digestibility and heart rate exist between animals with divergent RFI. Feeding behavior traits may be an effective biomarker trait for RFI in beef and dairy cattle. There are differences in mitochondrial acceptor control and respiratory control ratios between calves with divergent RFI suggesting that variation in mitochondrial metabolism may be visible at the genome level. Multiple genes associated with mitochondrial energy processes are altered by RFI phenotype and some of these genes are associated with mitochondrial energy expenditure and major cellular pathways involved in regulation of immune responses and energy metabolism.

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Weller, Joel, Harris Lewin, Micha Ron, George Wiggans e Paul VanRaden. A Systematic Genome Search for Genes Affecting Economic Traits Dairy Cattle with the Aid of Genetic Markers. United States Department of Agriculture, aprile 1999. http://dx.doi.org/10.32747/1999.7695836.bard.

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The objectives were to continue collection of semen for the US dairy bull DNA repository, to conduct a systematic search of the Holstein genome for economically significant economic trait loci (ETL), to develop and refine statistical techniques for the analysis of the data generated, and to confirm significant effects by genotyping daughters i Israel and additional US sons. One-thousand-seventy-six sons of eight US grandsires were genotyped for 174 microsatellites located on all 29 autosomes. ETL were detected for milk production traits on seven chromosomes. ETL for milk and fat yield and fat and protein percentage on BTA3 was mapped to between the markers BL41 and TGLA263. The 95% confidence interval for the ETL affecting fat percentage on BTA14 localized this ETL between the contromere and chromosome position 11 cM. This ETL was verified in the Israeli cattle population by genotyping an independent sample of cows from seven families. The radiation hybrid data for the centromeric region of BTA14 is defined by a single linkage group. Order of Type I genes within this region, CYC-FADK-TG-SQLE, is conserved between human and cattle. Thus, HSA8, the human homologue of BTA14, can be used to identify candidate genes for the ETL.

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Gutierrez, Gustavo A., P. Jeff Berger e Mary H. Healey. Joint Genetic Analysis of Conception and Maintenance of Pregnancy in Dairy Cattle Using a Linear-Threshold Model. Ames (Iowa): Iowa State University, gennaio 2008. http://dx.doi.org/10.31274/ans_air-180814-948.

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Weller, Joel I., Derek M. Bickhart, Micha Ron, Eyal Seroussi, George Liu e George R. Wiggans. Determination of actual polymorphisms responsible for economic trait variation in dairy cattle. United States Department of Agriculture, gennaio 2015. http://dx.doi.org/10.32747/2015.7600017.bard.

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The project’s general objectives were to determine specific polymorphisms at the DNA level responsible for observed quantitative trait loci (QTLs) and to estimate their effects, frequencies, and selection potential in the Holstein dairy cattle breed. The specific objectives were to (1) localize the causative polymorphisms to small chromosomal segments based on analysis of 52 U.S. Holstein bulls each with at least 100 sons with high-reliability genetic evaluations using the a posteriori granddaughter design; (2) sequence the complete genomes of at least 40 of those bulls to 20 coverage; (3) determine causative polymorphisms based on concordance between the bulls’ genotypes for specific polymorphisms and their status for a QTL; (4) validate putative quantitative trait variants by genotyping a sample of Israeli Holstein cows; and (5) perform gene expression analysis using statistical methodologies, including determination of signatures of selection, based on somatic cells of cows that are homozygous for contrasting quantitative trait variants; and (6) analyze genes with putative quantitative trait variants using data mining techniques. Current methods for genomic evaluation are based on population-wide linkage disequilibrium between markers and actual alleles that affect traits of interest. Those methods have approximately doubled the rate of genetic gain for most traits in the U.S. Holstein population. With determination of causative polymorphisms, increasing the accuracy of genomic evaluations should be possible by including those genotypes as fixed effects in the analysis models. Determination of causative polymorphisms should also yield useful information on gene function and genetic architecture of complex traits. Concordance between QTL genotype as determined by the a posteriori granddaughter design and marker genotype was determined for 30 trait-by-chromosomal segment effects that are segregating in the U.S. Holstein population; a probability of <10²⁰ was used to accept the null hypothesis that no segregating gene within the chromosomal segment was affecting the trait. Genotypes for 83 grandsires and 17,217 sons were determined by either complete sequence or imputation for 3,148,506 polymorphisms across the entire genome. Variant sites were identified from previous studies (such as the 1000 Bull Genomes Project) and from DNA sequencing of bulls unique to this project, which is one of the largest marker variant surveys conducted for the Holstein breed of cattle. Effects for stature on chromosome 11, daughter pregnancy rate on chromosome 18, and protein percentage on chromosome 20 met 3 criteria: (1) complete or nearly complete concordance, (2) nominal significance of the polymorphism effect after correction for all other polymorphisms, and (3) marker coefficient of determination >40% of total multiple-regression coefficient of determination for the 30 polymorphisms with highest concordance. The missense polymorphism Phe279Tyr in GHR at 31,909,478 base pairs on chromosome 20 was confirmed as the causative mutation for fat and protein concentration. For effect on fat percentage, 12 additional missensepolymorphisms on chromosome 14 were found that had nearly complete concordance with the suggested causative polymorphism (missense mutation Ala232Glu in DGAT1). The markers used in routine U.S. genomic evaluations were increased from 60,000 to 80,000 by adding markers for known QTLs and markers detected in BARD and other research projects. Objectives 1 and 2 were completely accomplished, and objective 3 was partially accomplished. Because no new clear-cut causative polymorphisms were discovered, objectives 4 through 6 were not completed.

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Saatchi, Mahdi, e Rohan L. Fernando. Empirical Progeny Equivalent for Genotyped Animals in Multi-breed Beef Cattle Genetic Evaluations Using Single-step Bayesian Regression Model. Ames (Iowa): Iowa State University, gennaio 2018. http://dx.doi.org/10.31274/ans_air-180814-483.

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