Genetic and Phenotypic Relationships Among Endocrine and Traditional Fertility Traits and Production Traits in Holstein-Friesian Dairy Cows

• Published in: Journal of dairy science 2002-04, Vol.85 (4), p.958-967
• Main Authors: Royal, M.D., Flint, A.P.F., Woolliams, J.A.
• Format: Article
• Language: English
• Subjects: Animal productions; Animals; Biological and medical sciences; Breeding; Cattle - genetics; Cattle - physiology; Female; fertility; Fertility - genetics; Fundamental and applied biological sciences. Psychology; genetic correlation; Genetic Variation; Genetics of eukaryotes. Biological and molecular evolution; Health Status; Lactation - genetics; Milk - chemistry; Milk - secretion; milk production; Phenotype; Population genetics, reproduction patterns; Pregnancy; progesterone; Progesterone - analysis; Reproduction - genetics; Terrestrial animal productions; Vertebrata; Vertebrates
• ISSN: 0022-0302; 1525-3198
• DOI: 10.3168/jds.S0022-0302(02)74155-6

The objective of this study was to estimate the heritability of a number of traditional and endocrine fertility traits in addition to d-56 predicted milk yield (MY56), and the genetic and phenotypic correlations between these traits. Various fixed effects such as season, year, herd, lactation number, diet, percentage Holstein (PCH) of the cow, and occurrence of uterine infection (UI), dystocia (DYS), and retained placenta (RP) were also investigated. Data collected for 1212 lactations of 1080 postpartum (PP) Holstein-Friesian dairy cows in eight commercial farms between 1996 and 1999 included thrice weekly milk progesterone samples, calving and insemination dates, various reproductive health records, monthly/bimonthly production records, three-generation pedigrees, and PCH information. Genetic models were fitted to the data to obtain heritabilitites and correlations using ASREML. Estimates of heritability for interval to commencement of luteal activity PP (lnCLA), length of the first luteal phase PP (lnLutI) and occurrence of persistent CL type I (PCLI) were 0.16, 0.17, and 0.13, respectively. Heritabilities for pregnancy to first service (PFS), interval to first service (IFS), and MY56 were 0.14, 0.13, and 0.50, respectively. Genetic regressions of lnCLA and lnLutI on PTA of the sire for milk, fat, and protein yields, and PIN95 were investigated. Regressions of lnCLA were positive and significant on fat yield, while regressions of lnLutI on both protein yield and PIN95 were negative and significant. Genetic correlations of endocrine fertility traits (lnCLA, lnLutI, and PCLI) with MY56 were high (0.36, P