The effects of genotype and week of lactation on milk yield, udder dimensions and linear body measurements of non-dairy ewes

Abstract

One hundred and ninety two records were taken weekly for twenty four (24) weeks from West African Dwarf (WD), the Yankasa (YN) and the West African Dwarf X Yankasa crossbred (XB) sheep . The traits evaluated were milk yield (MK), linear body measurements (LB) such as height at withers, (HT), body length (BL), heart girth (HG), shoulder width (SW), Tail length (TA), Neck length (NL), Neck circumference (NC), Face length (FA), Hind leg length (HL), Foreleg length (FL), Face length (FA), Ear length (EA), Head width (HW) and Rump height (RH) together with the following Udder dimensions (UD): Udder circumference (UC), Teat length (TL) and Teat circumference (TC). There was significant (P<0.05) influence of genotype on MK, WHT, HT, BL, TA, FL, HL, FA, EA and RH. The WD ewes produced more milk than either the YN or XB ewes. Average daily milk yield (ml) was 122.25, 90.88 and 108.8. The YN genotype was superior in all LBs except SW and NC than the WD and XB in the three genotypes. Height at withers was 59.08, 69.21 and 61.81 cm; BL 48.54, 55.08 and 54.49 cm and RH 62.88, 75.11 and 68.46 cm for WD, YN and XB ewes respectively. Since milk offtake is related to body weight and some linear body measurements, selection for WT, HG, SW, NL, NC, UC and TL in WD ewes could lead to higher milk and mutton production. 

Keywords: West African Dwarf, Yankasa, Yankasa x West African Dwarf, milk yield, weight, linear body measurement