Productive and Reproductive Capacity and Characteristics of the Thoracic Region for the Venezuelan Creole Goat

Populations of Creole goats in three regions were sampled. Breeding females were identified, characterized, and monitored. Traits were birth weight (BW), and one (M1), two (M2), three (M3), four (M4), and five-month weights (M5), milk-yield level (MY), kidding intervals (CI), mature weight (MW), chest width (CW), chest depth (CD), chest height (CH), wither height (WH), and thoracic perimeter (TP). MTDFREML Package was used. Fixed effects included year of birth and fractions of loci homozygous Creole, homozygous exotic, and heterozygous Creole-exotic as genetic group and as co-variables, and animal as random. For growth traits maternal environment was also fit as random, and sex, litter size, parity, and season as fixed factors. Growth traits and MY differed statistically among regions, and among genetic groups. Region effect was consistent along all age weights. Heritability estimates for BW, M1, M2, M3, M4, and M5 were of 0.59, 0.25, 0.53, 0.32, 0.53, and 0.59; and for MY, CI, CD, CW, WH, CH, and TP of 0.37, 0.00, 0.55, 0.48, 0.54, 0.41, and 0.78 respectively. Enough additive genetic variation seems to exist to select from for genetic changes in production traits. Maternal environment shows to be important for growth traits. Variation in growth traits due to region effect seems to exist. A high specific combining ability seems to exist for growth and milk-yield traits. Morphological traits show to be highly influenced by the additive effect of genes, and the phenotypic variation similar or greater than those reported in the cited literature from others population of Creole goats. More research is needed.