UDC 636.082
DOI: 10.36871/vet.zoo.bio.202212113
Authors
Felix D. Yakimov,
Olga V. Tulinova,
All-Russian Research Institute of Genetics and Breeding of Farm Animals – branch of
Federal Research Center of Animal Husbandry – VIZ named after Academician L. K. Ernst,
St. Petersburg, Russian Federation
Abstract
The purpose of the study was the influence of Ayrshire bulls on economically useful signs of daughters, which were carried out according to a sample of 1446 first-calving cows from 58 bulls. On average, the cows in the sample were calved at the age of 27,3±0,1 months. With a live weight of 487±0,4 kg and milked for lactation 6409±33,4 kg of milk .The one-way analysis of variance (ANOVA) method the strength of the influence of breeding bulls was calculated, which strongly influenced the growth and development of proband in different periods of ontogenesis: height at withers (58,0 %), live weight at birth, at 10, 12, 18 months (from 49,0 to 51,9 %) and on the level of productivity of daughters (41,6 %), which is quite high. A high correlation between the live weight of heifers at birth, at 10, 12, 18 months with the height at the withers of cows after the first calving was revealed (+0,555; +0,487; +0,487; +0,509) and with milk yield for the first lactation (+0,591; +0,522; +0,550; +0584), as well as the height at the withers with milk yield (+0,457). Therefore, the productivity of cows after the 10st lactation depends on their development in heifers. It was found that the descendants of breeding bulls who exceeded the average sample values for milk yield also had a large live weight at 12 and XNUMX months and height at the withers.
Keywords
age, live weight, milk yield, measurements, cow, bull, Ayrshire breed, power of influence, variability
