Effect of doeling traits at weaning on subsequent replacement doe fitness traits in a multi-breed meat goat herd

Abstract

This study evaluated how doeling traits at weaning influence their fitness as replacement does. Boer (n = 60), Kiko (n = 102), Spanish (n = 96), Boer-cross (n = 138) and Myotonic (n = 20) doelings were weaned at 3 months of age and classified by weaning litter type (single- or multiple-kid type), weaning weight ratio group (WWR; low, moderately low, moderately high, or high) and breed-type. Survival and reproductive output in the replacement does as 2-yr-olds were recorded. The herd was semi-intensively managed on humid subtropical pasture. Boer doelings had lower (P < 0.05) survival rates than Boer-cross, Kiko and Spanish doelings to different developmental end-points. Survival rates from weaning to yearling age and first breeding were significantly lower for low WWR doelings than for high WWR doeling. Boer doelings had significantly lower kidding and weaning rates and smaller litter sizes at kidding and weaning than other breeds. Low WWR doelings had lower (P < 0.05) reproductive values at kidding and weaning than doelings in the three higher WWR groups. The three higher WWR groups did not differ for any reproductive trait. Litter type of weaned doelings did not affect their subsequent survival and reproductive rates. Selection based on breed-type and WWR affected replacement doeling performance. Straightbred Boer doelings and low WWR doelings exhibited reduced fitness levels through their first production year.