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Full-Text Articles in Animal Sciences
Direct And Correlated Responses To Two-Stage Selection For Ovulation Rate And Number Of Fully Formed Pigs At Birth In Swine, A. Ruiz-Flores, R. K. Johnson
Direct And Correlated Responses To Two-Stage Selection For Ovulation Rate And Number Of Fully Formed Pigs At Birth In Swine, A. Ruiz-Flores, R. K. Johnson
Department of Animal Science: Faculty Publications
Our objectives were to estimate responses and genetic parameters for ovulation rate, number of fully formed pigs at birth, and other production traits following two-stage selection for increased ovulation rate and number of fully formed pigs. Eight generations of selection were practiced in each of two lines. One selection line was derived from a line that previously selected eight generations for an index to increase ovulation rate and embryonic survival (the IOL pigs). The other selection line was derived from the unselected control line of the index selection experiment (the COL pigs). The control line (C) was continued with random …
Identification Of Quantitative Trait Loci Affecting Reproduction In Pigs, J. P. Cassady, R. K. Johnson, Daniel Pomp, G. A. Rohrer, L. Dale Van Vleck, E. K. Spiegel, K. M. Gilson
Identification Of Quantitative Trait Loci Affecting Reproduction In Pigs, J. P. Cassady, R. K. Johnson, Daniel Pomp, G. A. Rohrer, L. Dale Van Vleck, E. K. Spiegel, K. M. Gilson
Department of Animal Science: Faculty Publications
The objective of this research was to identify chromosomal regions harboring QTL affecting reproduction in pigs. A three-generation resource population was developed by crossing low-indexing pigs from a randomly selected control line (C) with high-indexing pigs of a line selected for increased index of ovulation rate and embryonic survival (I). Differences between Lines I and C at Generation 10 were 6.7 ova and 3.3 fetuses at 50 d of gestation and 3.1 fully formed and 1.6 live pigs at birth. Phenotypic data were collected on F2 females, born in three replicates, for ovulation rate (n = 423), age at …
Candidate Gene Analysis For Loci Affecting Litter Size And Ovulation Rate In Swine, R. C. Linville, Daniel Pomp, R. K. Johnson, M. F. Rothschild
Candidate Gene Analysis For Loci Affecting Litter Size And Ovulation Rate In Swine, R. C. Linville, Daniel Pomp, R. K. Johnson, M. F. Rothschild
Department of Animal Science: Faculty Publications
A candidate gene approach was used to determine whether specific loci explain responses in ovulation rate (OR) and number of fully formed (FF), live (NBA), stillborn, and mummified pigs at birth observed in two lines selected for ovulation rate and litter size compared with a randomly selected control line. Line IOL was selected for an index of OR and embryonic survival for eight generations, followed by eight generations of two-stage selection for OR and litter size. Line C was selected at random for 16 generations. Line COL, derived from line C at Generation 8, underwent eight generations of two-stage selection. …