Effect of Mating Ewe Lambs on Lifetime Productive Performance

Publisher Website
Google Scholar
Abstract
A total of 351 Dala and Steiger ewes were included in a study to investigate the effect of lambing at 1 yr of age on lifetime productive performance. Of the 118 ewes lambing at 1 yr of age 74% weaned lambs. These ewes weaned slightly less lambs at 2 yr of age but subsequent performance was not significantly different from ewes lambing for the 1st time at 2 yr of age (control ewes). Weaning weights of lambs from ewes that had lambed at 1 yr of age was not depressed at older ages compared to control ewes but fleece weight from these ewes were depressed, most markedly at the 2 yr old stage. Ewes that lambed at 1 yr of age were culled about half a year earlier than control ewes, but still had a slightly greater number of production years (number of years a ewe weaned a lamb) by about 0.35 yr, although the latter difference was not significant. The weights of lamb weaned in a ewes lifetime did not differ significantly among experimental groups. There were significant differences between Dala and Steigar ewes for a number of traits studied. Those ewes lambing 1st at 2 yr of age were subdivided into those that showed estrus as ewe lambs and those that did not. In general there was no significant difference in production between these 2 groups. Mating of ewe lambs to lamb at 1 yr of age is a practical and feasible procedure. While it may not increase lifetime productive performance, there is no evidence from this study that it will decrease it. Lambing at 1 yr of age also permits accurate identification of a ewes breeding value for reproductive traits at an earlier age and should lead to a shorter generation interval and both these effects should result in greater genetic progress for productive traits of economic importance.

This publication has 7 references indexed in Scilit: