A comparison of methods of estimating milk intake of lambs and milk yield of ewes at pasture

Abstract

The milk intake of lambs sucking strong-wool Merino ewes at pasture was estimated by the lamb-suckling technique. This measure of milk production was compared with the estimate of the milk yield of the same ewes obtained after oxytocin injections. The ewes were divided subjectively into two classes, those that would stand for the lamb throughout the lamb-suckling test period and those that would not. During the first four weeks of lactation the ratios of the oxytocin estimate to the lamb suckling estimate were 99:100 (P> 0.10) for the former class and 106 : 100 (P<0.01) for the latter class. The corresponding ratios during the last six weeks were 104 : 100 (P> 0.05) and 116 : 100 (P<0.01). It was concluded that for the former class the two techniques are in good agreement.