Studies on the Genetic Constitution of Black - and - White Dairy Cattles Raised in Tahirova State Farm*

YAHYA TUNCAY TUNA
Trakya University Agricultural Faculty, Department of Animal Science, 59030 Tekirdag, Turkey

Abstract

TUNA, YAHYA TUNCAY, 2004. Studies on the genetic constitution of Black - and - White dairy cattles raised in Tahirova State farm. Bulg. J. Agric. Sci., 10: 367-370

In this study 1504 individual milk yield records were analysed to evaluate the breeding potential of dairy cattle raised in Tahirova State Farm. Milk yields records of 468 Black and White cattle were obtained from the period of 1978 - 1995. Heritability of reproductive (first breeding age-FBE; first calving age-FCA; calving interval-Cl; service period-SP and days in dry-DID) and milk yield (lactation length-LL; 305 day milk yield-305d-MY) traits were estimated from the data. Phenotypic correlations between reproductive traits and between milk yield traits were also calculated.

Key words: Black - and - White, dairy, cattles, Tahirova state, genetic constitution

*This study is section from the Ph. D. Thesis prepared by Y. T. Tuna