Milk progesterone measures to improve genomic selection for fertility in dairy cows

摘要: Improved reproductive performance has a substantial benefit for the overall profitability of dairy cattle farming by decreasing insemination and veterinary treatment costs, shortening calving intervals, lowering rate involuntary culling. Unfortunately, low heritability classical fertility traits derived from data makes genetic improvement traditional animal breeding slow. Therefore, there is an interest in finding novel measures that have higher or using genomic information to aid selection fertility. The objective this thesis was explore use milk progesterone (P4) records improve cows. In first step, in-line define endocrine investigated, parameters estimated. Several defined were heritable, showed reasonable repeatability. Also, correlation production with considerably lower than correlations traits. next step 17 quantitative trait loci (QTL) associated traits, identified on Bos taurus autosomes (BTA) 2, 3, 8, 12, 15, 17, 23, 25 genome-wide association study single nucleotide polymorphisms. Further, fine-mapping target regions BTA 2 several variants potential candidate genes underlying Subsequently, optimal evaluations investigated; empirical theoretical predictions single-trait models, I more predictive ability accuracy prediction also substantially improved when combined multi-trait prediction. Finally, deterministic predictions, combining cow training population measured commencement luteal activity (C-LA), bulls daughter observations investigated. Results fertility, no investing goal based However, considering biological like C-LA, are available limited number farms.