Calculation of adjustment factors for standardizing lactations to mature age and 305-day and estimation of heritability and repeatability of standardized milk yield of simmental cattle reared on Kazova State Farm


Cilek S., Tekin M. E.

TURKISH JOURNAL OF VETERINARY & ANIMAL SCIENCES, cilt.30, ss.283-289, 2006 (SCI İndekslerine Giren Dergi) identifier identifier

  • Cilt numarası: 30 Konu: 3
  • Basım Tarihi: 2006
  • Dergi Adı: TURKISH JOURNAL OF VETERINARY & ANIMAL SCIENCES
  • Sayfa Sayıları: ss.283-289

Özet

Adjustment factors of lactation milk yield to mature age and 305-day were calculated and heritability and repeatability of milk yield were estimated for Simmental cows reared on Kazova State Farm. A total of 1549 lactation records of Simmental cows reared on Kazova State Farm between 1992 and 2002 were used. The factors for standardizing incomplete lactations to 305-day were estimated by taking 7 calving age groups into consideration (2, 3, 4, 5, 6-8, 9 and 10 years of age and older). The factors for standardizing to mature equivalent estimated by polynomial regression are between the 24(th) and 143(rd) month and older.