A comparison of the performance of Dorset, Corriedale and Romney sheep during lactation

The milk producltion oh Dorset. Corriedale and Romney ewes was co’mpared while they reared twins during a 12-week lactation. Total average m#ilk yields were 188 t 8.61, 160 +4.22 and 135 * 6.80 kg, respectively. Breed differences were significant. Lamb liveweight gains were positively related to milk yield’s for the Dorsets and the Rolmneys but there was a negative correlation for the Corricdales. At weaning the mean total weigbts of lamb per ewe were 55.2 & 1.67, 52.4 & 1.78 and 49.0 f 1.25 kg for Dorsets, Corriedales and Romneys, respectively. The advantages of the Dorset in terms of milk production and lamb growth rates were’ highlighted. With o’ther characteristics such as a lo’ng breeding seasosn and above-average prolificacy, the suitability of the breed’s use fo’r intensified lamb production is discuss#ed. The co’nsideralble difference in performance between the Corriedales and the Romneys under the environmental conditions of this experiment is also’ discussed.