Department of Animal Production, Faculty of Agriculture and Forestry, University of Duhok, Kurdistan Region, Iraq
Receive Date: 26 July 2013,
Revise Date: 20 October 2013,
Accept Date: 30 October 2013
Characteristic of the udder, milk traits and their relationship were investigated in 32 Awassi ewes raised in a commercial flock. Commencing one month after lambing milk yield was recorded at monthly intervals until the ewes were dried. Also, the udder traits were measured, including udder width, udder circumference, udder length, distance between teats and length and diameter of both teats. Results revealed that sex of lambs and stage of lactation affected (P<0.05) test day milk yield. The age of dam had no effect on test day milk yield, but affected (P<0.05) left teat diameter and right teat length. Also, sex of lambs affected (P<0.05) right teat length. As the milk yield increased there was an increase in udder circumference and teat diameter (P<0.05). Milk yield positively correlated with all udder measurements except with udder length and right teat length. Also, positive and high correlation coefficients were observed between udder circumference and udder width (r=0.679), distance between teat (r=0.699) and left teat diameter (r=0.417) as well as between udder width and distance between teats (r=0.732). A positive relationship (P<0.01) among teat measurements (r=0.596-0.908) was observed. According to the results of principal component analysis, udder circumference and right teat length were the best predictors for milk yield in Awassi ewes.
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