Genetic parameters for milk production and body size in New Zealand Holstein-Friesian and Jersey

摘要: Abstract 178 and 158 half-sib groups of 7345 Holstein-Friesian 3967 Jersey primiparous cows were milk recorded body size traits subjectively assessed. In the analysis models differing with respect to sire effect used assess selection ancestors. Heritabilities for fat, protein 0.26, 0.26 0.28 0.24 Jersey, respectively. Body weight stature showed heritabilities 0.25 0.29 0.16 0.23 which are comparable those yield traits. This indicates that current breeding schemes could be genetically influence Heritability estimates all production consistently increased in both breeds when paternal grandsires included model, thus alleviating selection. Genetic correlations between large positive, ranging from 0.68 0.87. With 0.46, moderately positively correlated yields breeds, indicating considered as criteria restrict response potentially increase overall economic merit, especially selecting or yield.