Influence of crossbreeding and non genetic factors on doe fitness traits of Boer F1 and foundation breeds in southeastern United States

The effect of breed on fitness traits and the effects of breed, weaning weight ratio (WWR) and weaning type (WTYPE) on doeling development were studied in two objectives. In Objective 1, Boer (n = 20), Kiko (n = 162), Spanish (n = 150), Boer × Kiko (n = 133) and Boer × Spanish (n=112) meat goat does were evaluated for breed effects on doe fitness traits across six years. Body weights of Boer × Kiko does were heavier (P \u3c 0.05) than Boer does but Spanish × Boer does did not differ to Boer does at breeding. At breeding, kidding and weaning the older does were heavier (P \u3c 0.05) than younger does. Kiko does had lower (P \u3c 0.05) litter weight (LW) at kidding than Kiko × Boer does. Breeding body weight increased (P \u3c 0.05) the litter size (LS) and LW at kidding. At weaning LS and LW of Boer F1 did not differ among purebreds but were higher (P \u3c 0.01) than that of Boer does. At kidding the worm fecal egg count of Kiko × Boer does was higher than that of Kiko does. For Objective 2, Boer (n = 60), Kiko (n = 102), Spanish (n = 96), Boer-cross (n = 138) and Myotonic (n = 20) weaned doelings across seven years were evaluated to determine if WTYPE, WWR and breed influenced subsequent survival and reproduction up to the second weaning of their own kids. Ratios were classified as low (LL), moderately low (ML), moderately high (MH) and high (HH). Reproductive rates, survivability up to different stages and LS were higher (P \u3c 0.05) for Boer-cross than Boer does but similar to non-Boer purebred does. Fitness performance was lower (P \u3c 0.05) for LL does than ML, MH and HH does. The latter three did not differ. Reproductive and survival rates were not affected by WTYPE. Hence, Boer-cross does exhibited similar merit for reproductive and health traits as Kiko, Spanish and Myotonic does but better than Boer does in low input management conditions. Weaning weight ratio affected the fitness traits but WTYPE did not