Published online by Cambridge University Press: 02 September 2010
Wild yak males were crossed with domesticated female yaks to produce a breeding herd of crossbred animals. The milk production of the progeny of this herd was measured in the present study. Yaks were milked once daily after prior suckling of the calf. Yaks were allowed to graze for 15 hiday on high-altitude (3200 to 3500 m) pastures. No supplementary food was given. Average daily milk yield of 1·77 (s.e. 0·16) kg and milk yield over 120 days, 212·2 (s.e. 20·2) kg were significantly higher (P < 0·01) than the corresponding figures for unimproved domestic yaks (1·53 (s.e. 0·10) kg and 184·6 (s.e. 10·5) kg respectively). The fat content of milk from crossbred yaks, 52 (s.e. 2·9) glkg, was not significantly different from that of unimproved animals, 53·5 (s.e. 4·1) g/kg.