文摘
Goat breeding research in Mexico began in 1980 with studies on breed and crossbreed comparisons involving local goats and goats from specialized breeds imported from the USA, using data from a large goat breeding centre, in Tlahualilo, Durango, located in Northern Mexico. Genetic groups were purebred and crossbreed goats involving recurrent backcrosses with imported breeds and local Granadina breed with nondescript local goats. Traits analyzed include milk production, kidding intervals, kidding distributions, kid weights, survival and stayability. Results showed the higher milk production efficiency of Alpine, Saanen and Toggenburg, compared to local populations, but there were smaller advantages from the use of Nubian or Granadina goats. Granadina and Nubian goats had higher kid survival rates, longer breeding seasons and were more efficient for meat production. Evidence for higher stayability for adult Alpine and lower for Saanen goats was reported. More recently, research on meat goat breeding involving local goats and other genetic groups such as Boer, Nubian and breed crosses have been done. Research on genetic parameter estimation began with estimates of heritability for birth weight in kids and repeatabilities for several milk production and reproduction traits, and has continued until now. It is currently related to milk production and composition traits recorded in dairy breeding populations of Alpine, Saanen and Toggenburg goats in the State of Guanajuato. These parameters are being used together with mixed-model methodology for the genetic evaluation of these populations for milk, fat and protein production. Recent studies (2006) regarding the distribution of polymorphism for the α-s1 locus in several goat populations in Mexico and its effects on milk traits in Mexican dairy goats were conducted.