THE EFFECT OF AVERAGE DAILY GAIN AND AGE AT FIRST CALVING ON REPRODUCTIVE AND MILK PRODUCTION TRAITS OF BROWN SWISS AND HOLSTEIN FRIESIAN CATTLE

Bayram B., Yanar M., Akbulut O.

BULGARIAN JOURNAL OF AGRICULTURAL SCIENCE, cilt.15, sa.5, ss.453-462, 2009 (SCI-Expanded) identifier identifier

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 15 Sayı: 5
  • Basım Tarihi: 2009
  • Dergi Adı: BULGARIAN JOURNAL OF AGRICULTURAL SCIENCE
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Sayfa Sayıları: ss.453-462
  • Anahtar Kelimeler: heifers, daily gain, age at first calving, reproduction traits, milk yield, Holstein Friesian, Brown Swiss, DAIRY HEIFERS, ACCELERATED-GROWTH, FEEDING LEVEL, PERFORMANCE, RATES, DIETS
  • Atatürk Üniversitesi Adresli: Evet

Özet

The purpose of the study was to determine the effects of average daily gain and age at first calving on the reproductive and milk production traits of Brown Swiss (BS) ad Holstein Friesian (HF) cattle. For this purpose, daily gains and ages at first calving were divided into two groups which were below the average called as the "slow" or "early" groups and above the average named as "moderate" or "late" groups respectively. BS heifers in the moderate group reached the first insemination age and first calving age 103.7 and 101.7 days earlier (P<0.01) than these in the slow group respectively. The corresponding values for HF heifers were 37.8 and 29.5 days respectively and were not significant. While the average daily gain had negative effects on reproduction traits following the first calving, the daily gain of BS had no effect on the milk production traits in all parities. HF heifers in the moderate group had higher (P<0.05) actual (585 kg) and 305 days milk yield (324 kg) in the second parity.