Evaluation of Environmental Factors on Important Production Traits of Iranian Buffaloes

In this research، the effect of environmental factors on 15507 records of production traits (milk yield، fat yield، fat percentage، protein yield and protein percentage) was studied. Data collected from 163 buffaloes herds from Guilan، Mazandaran، West Azerbaejan، Khuzestan and Ardebil provinces by Animal Breeding Organization of Iran during 16 years (1992-2008). The environmental factors were state، herd nested within state، lactation period، age at calving، season of calving and year of calving، analysed by GLM procedure in SAS software. Least square means and standard errors of milk yield، fat yield، fat percentage، protein yield and protein percentage were 1904. 16±6. 51kg، 123. 21±0. 46kg، 6. 41±0. 01%، 90. 65±0. 50kg، 4. 16±0. 01%، respectively. Result indicated that age at calving was significant for fat percentage only lactation period significantly influenced all traits، except fat percentage (P<0. 01). The effect of all other factors on all traits was significant.