Coyote (Car1i.s1ntran.s)depredation is a chronic problem for sheep producers in the western United States. Due to increasingly localized control efforts, behaxior of individual coyotes in sheep-ranching entironments is becoming a more important consideration. We radiotracked 14 coyotes on a year-round sheep-ranching facility in north-coastal California during September 1993-December 1995. Breed...

Scrapie is a fatal neurodegenerative disease of sheep and goats belonging to the group of transmissible spongiform encephalopathies (TSE). TSEs are characterised by distinctive pathology, the involvement of a hostencoded prion protein (PrP) in disease development and genetic control of susceptibility. Polymorphisms in three different codons of the ovine prion protein (PrP) gene (136, 154, 171) ...

Implementation of genomic selection in sheep breeding provides a number of challenges, compared to dairy cattle, because of the higher genetic diversity between and within sheep breeds, the cost of maintaining reference populations and the limited ability of individual breeders to invest in genotyping. Within this study, we compare theoretical and realized genomic prediction accuracies for trai...

BACKGROUND Following EU decision 2003/100/EC Member States have recently implemented sheep breeding programmes to reduce the prevalence of sheep with TSE susceptible prion genotypes. The present paper investigates the progress of the breeding programme in the Netherlands. The PrP genotype frequencies were monitored through time using two sets of random samples: one set covers the years 2005 to ...

Factors affecting ewe prolificacy (number of lambs born per ewe lambing) were evaluated using records on 9705 Targhee, 12,721 Suffolk, and 7231 Polypay lambings from flocks participating in the US National Sheep Improvement Program. Factors considered were ewe age and season of lambing. Prolificacy was affected by age of the ewe (P<0.001) and was highest for ewes lambing between 4 and either 7 ...

Scrapie is a transmissible spongiform encephalopathy in sheep and an example of a disease that may be controlled through breeding for disease resistance. Member states of the European Union have introduced strategies for breeding against scrapie based on the selection of genetically resistant breeding rams. An ambitious strategy adopted in The Netherlands consisted of selecting resistant rams f...

Biological indicators that can be used to predict the sensitivity of animals to environmental changes are of interest to the sheep industry for economic and welfare reasons. The coefficient of variation of fibre diameter (HCVFD) is a potential indicator of environmental sensitivity and tends to be negatively correlated with fatness. To further understand the association of HCVFD with the sensit...

BACKGROUND Susceptibility of sheep to scrapie infection is known to be modulated by the PrP genotype of the animal. In the Netherlands an ambitious scrapie control programme was started in 1998, based on genetic selection of animals for breeding. From 2002 onwards EU regulations required intensive active scrapie surveillance as well as certain control measures in affected flocks.Here we analyze...