Akademik Veri Yönetim Sistemi
ARCHIV FUR TIERZUCHT-ARCHIVES OF ANIMAL BREEDING, cilt.54, sa.5, ss.515-524, 2011 (SCI-Expanded)
Though East Friesian sheep are known to have very high milk yield, their various degree crosses may have different levels of milk yield under different conditions due to genotype x environment interaction. The major purpose of this study was to investigate whether increasing milking frequency for a short period (21 days) increases milk yield in two East Friesian crosses, Tahirova and Sonmez sheep. Tahirova is 75% East Friesian and 25% Kivircik, while Sonmez is 75% Tahirova and 25% Sakiz (Chios). Two milking groups were formed and were treated the same in terms of feeding and management. The sheep in the 4x group were milked 4 times a day after weaning for a short period, namely 21 days and then were milked twice a day for the rest of the lactation. The sheep in the 2x group were milked twice a day throughout the whole milking season. Repeated measures analyses indicated that overall differences between the 2x (520.68g) and 4x (873.03g) groups were highly significant for milk yield (P<0.01). Parity differences were significant in the treatment group and the 3rd lactation animals responded better to the 4x treatment (P<0.01), but they were non-significantly different than the 2nd lactation animals in the 2x group. Sheep in the 4x group had higher milk fat yield (P=0.02) but the groups were similar in terms of fat percentage (P=0.11). Differences between the breeds were highly significant (P<0.01) also. Tahirova breed, which has a higher percentage of East Friesian had a daily milk yield of 566.66g, while Sonmez breed with a lower percentage of East Friesian produced a higher daily milk yield of 827.05g. Results of this study suggests that increasing milking frequency for a short time increases milk yield throughout lactation, especially for older animals, and sheep with too high East Friesian breeding may have lower milk yield than those with lower East Friesian breeding.