Life Sciences Commons^™

Overall Animal Welfare Reviewed. Part 3: Welfare Assessment Based On Needs And Supported By Expert Opinion, M.B.M. Bracke, B. M. Spruijt, J.H.M. Metz

Assessment of Animal Welfare Collection

Welfare concerns what matters to animals from their point of view. What matters to animals is their state of need. Satisfaction and frustration of needs are associated with emotional states, the subjective experience of which directly determines the welfare status of an animal. Because emotional states are difficult to assess, overall welfare assessment (OWA) is best approached as an assessment of needs.

For actual OW A a list of needs must be formulated. Different authors have formulated different lists. From these lists a concept need-list was constructed. For validation the needs-based approach for OWA was discussed in interviews with experts …

Identification Of Quantitative Trait Loci Affecting Female Reproductive Traits In A Multigeneration Meishan-White Composite Swine Population, G. A. Rohrer, J. J. Ford, T. H. Wise, J. L. Vallet, R. K. Christenson

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

A multigeneration crossbred Meishan- White composite resource population was used to identify quantitative trait loci (QTL) for age at first estrus (AP) and the components of litter size: ovulation rate (OR; number of ova released in an estrous period) and uterine capacity (UC). The population was established by reciprocally mating Meishan (ME) and White composite (WC) pigs. Resultant F1 females were mated to either ME or WC boars to produce backcross progeny (BC) of either ¾ WC ¼ ME or ¼ WC ¾ ME. To produce the next generation (F₃) , ¾ WC ¼ ME animals were mated …

Responses In Ovulation Rate, Embryonal Survival, And Litter Traits In Swine To 14 Generations Of Selection To Increase Litter Size, Rodger K. Johnson, Merlyn K. Nielsen, David S. Casey

Department of Animal Science: Faculty Publications

Eleven generations of selection for increased index of ovulation rate and embryonal survival rate, followed by three generations of selection for litter size, were practiced. Laparotomy was used to count corpora lutea and fetuses at 50 d of gestation. High-indexing gilts, approximately 30%, were farrowed. Sons of dams in the upper 10% of the distribution were selected. Selection from Generations 12 to 14 was for increased number of fully formed pigs; replacements were from the largest 25% of the litters. A randomly selected control line was maintained. Responses at Generation 11 were approximately 7.4 ova and 3.8 fetuses at 50 …