Gotz K.-U.,Institute For Tierzucht
Zuchtungskunde | Year: 2016
The report of the Scientific Advisory Board of the German Ministry of Agriculture has been widely discussed. The report analyses problems of modern animal husbandry, gives recommendations for improvements of legislation and controlling and describes which policy measures could support the transformation process of animal husbandry in Germany. However, the report does not present an ethical theory which would give a justification for the claims and allow for a priorisation of measures. This paper deals with some ethical questions from a pragmatic point of view and describes the role of animal science in the transformation process.
Preliminary study to determine extent of linkage disequilibrium and estimates of autozygosity in Brazilian Gyr dairy cattle [Estudo preliminar sobre a extensão do desequilíbrio de ligação e estimativas de autozigose em bovinos leiteiros da raça Gir]
Neves H.H.R.,Sao Paulo State University |
Desiderio J.A.,Sao Paulo State University |
Pimentel E.C.G.,Institute For Tierzucht |
Scalez D.C.B.,Sao Paulo State University |
Queiroz S.A.,Sao Paulo State University
Archivos de Zootecnia | Year: 2015
Genotypes of 25 artificial insemination sires were used to study the extent of linkage disequilibrium (LD) and the correspondence between pedigree and SNP-based estimators of inbreeding in Brazilian Gyr dairy cattle. Overall, 24,020 SNPs had minor allele frequencies (MAF) greater than 5 % and were used to calculate two measures of LD (r² and D’) for all pairs of markers in each autosome. LD was also used to estimate the effective population size (Ne) at different prior generations. Individual inbreeding coefficients (F) were estimated using either pedigree information (Fped, pedigree traced back up to 9 generations) or marker information. Marker-based estimates of F were derived based on the excess homozygosity (Fhet) in SNP markers and the estimated proportion of the genome located in runs of homozygosity (Froh). The mean LD between adjacent markers averaged across all autosomes was approximately 0.20 and 0.75, measured using r² and D’. Useful LD was identified between markers separated by up to 100 kb when screening this sample of Gyr dairy cattle. The effective population size showed a consistent trend of decay along time, falling below 56 in the last three generations. Weaker correspondence between individual inbreeding estimates based on runs of homozygosity and pedigree was verified in the present study (estimated correlations between Fped and Froh varied from 0.32 to 0.42). It appears to be feasible to apply genomic selection to Gyr cattle in Brazil, but further studies on the extent of linkage disequilibrium using a larger sample of this population are needed. © 2015, Universidad de Cordoba. All rights reserved.
Plieschke L.,Institute For Tierzucht |
Edel C.,Institute For Tierzucht |
Bennewitz J.,University of Hohenheim |
Emmerling R.,Institute For Tierzucht |
Gotz K.-U.,Institute For Tierzucht
Zuchtungskunde | Year: 2014
The aim of this study was to investigate imputation quality from two widely used imputation software packages (Flmpute and findhap) in imputing from 50k to HD. Three different aspects with respect to imputation quality were investigated: (1) differences between software programs, (2) differences in the number of HD-genotyped ancestors for four different groups of animals and (3) differences in marker coverage between chromosomes. For this purpose the Illumina chip annotations of two 50k chips (BovineSNP5O vi and v2) and the HD chip (BovineHD) were examined to find large physical gaps between adjacent SNPs or areas on the chromosome with a low marker density. After that, both programs were tested under routine conditions to assess the completeness of imputation and the amount of computational resources required. It turned out that imputation quality is influenced by differences between chromosomes and by differences between groups of animals with respect to the degree of HD genotyped ancestors in the reference population. Both differences had a greater impact on the performance of flndhap as compared to Flmpute. Furthermore using Flmpute resulted in higher imputation accuracy in the considered categories of this study. © Verlag Eugen Ulmer, Stuttgart.
Neuner S.,Institute For Tierzucht |
Gotz K.-U.,Institute For Tierzucht
Zuchtungskunde | Year: 2011
Genomic selection in dairy cattle breeding programs improves reliabilities for functional traits. Despite previous expectations, results in literature indicate that selection response in functional traits might decrease in intense genomic breeding programs. We examined the consequences of moderate genomic breeding programs on functional traits in the Bavarian Simmental population by means of deterministic calculations. Our calculations comprised all fourteen traits of the current aggregate genotype in Bavarian Simmental. Our results show that genetic gain in protein yield can be increased by 10% assuming a realistic proportion of unproven bulls. Genomic selection in our scenarios hardly affected the expected responses in functional traits. However, some traits showed undesired responses which could be alleviated by using a different breeding goal with higher weights on functional traits. © Verlag Eugen Ulmer, Stuttgart.
Zankl A.,Tiergesundheitsdienst Bayern e.V. |
Gotz R.,Tiergesundheitsdienst Bayern e.V. |
Pausenberger A.,Pfizer |
Dodenhoff J.,Institute For Tierzucht |
Wittmann W.,Institute For Tierzucht
Praktische Tierarzt | Year: 2011
A study dealing with the effects of vaccination against boar taint was carried out at the Bavarian Regional Institute for Agriculture, centrally coordinated by the Bavarian Animal Health Services e. V. It focused on the data collected from nursery, fattening and slaughter of a total of 256 male piglets from two batches of a bavarian piglet producer with 300 sows (German Landrace/Large White crossbreads). At day 0 the pigs were randomly assigned to three treatment groups: 125 animals in group 1 were surgically castrated as usual, 121 pigs in group 2 were kept entire for vaccination with Improvac ® during fattening and a small group of 10 animals was kept entire to serve as control group 3. Pigs in group 2 were vaccinated at the beginning of the fattening period and four to six weeks before slaughter. Whereas, apart from the losses, the results from the nurseries of both castrated and uncastrated piglets were nearly the same, significant differences were found in the results from fattening and slaughter. Vaccinated animals performed significantly better during fattening period in important parameters like daily weight gain and had a better food conversion rate. Carcases of vaccinated animals contained more meat and less fat. Significantly more vaccinated than castrated pigs were arranged in grade E. Due to the improvements in fattening and slaughter performance vaccinated animals yielded more favourable economic results. © Schlütersche Verlagsgesellschaft mbH & Co. KG.