Some factors influencing peak yield and days attain to peak yield in Friesian cattle in the central region of Iraq

[摘要] This study was under taken on 950 lactation records kept at Iraq-Jordinian company / Dujaila- Wasit Governorate during a period from 2001-2003.to evaluate the effect of some nongenetic factors (age at 1st calving,parity,season of calving ,year of calving and service period ) on peak milk yield and days to attain peak yield .The least-squares means for peak milk yield and days to attain peak yield were :14.252± 4.763 kg and 47.528 ± 24.121 days.Peak milk yield was significantly influenced (p<0.05) by season and year of calving ( p<0.01). Days to attain peak yield was significantly ( p<0.05) influenced by year of calving.

[学科分类] 土木及结构工程学