Abstract
L.V. Karlova, O.V. Lesnovska*, I.V. Deberina and O.G. Gavrilina
We analyzed the influence of the constitution type of cows of Ukrainian black-and-white milk breed on their milk production and reproductive ability. Broad-type cows probably dominated over age equivalent of narrow-bodied type by chest-broad and loin-broad indexes by 2.75 (11.2%; P>0.001) and 1.35 (5.04%; P>0.01). The model deviation for broad-bodied and narrow-bodied cows was +8.77 and -6.32, respectively. According to the main linear measurements of the first-born of a broad-leaved type of constitution, We revealed that broad-bodied cattle dominated of their narrow-bodied age mates by the height at withers (by 0.9%), chest depth – by 7.6%, chest width – by 8.5%, loid width – by 8.7%, body length by 10.1%, girth by 3.2%, and the cannon bone circumference by 1.6%. The difference in ratio between relative decline of growth and annual of cattle with different constitutional types was revealed. The broad-bodied yearlings had higher (84.1 ± 1.89) than narrow-bodied (81.2 ± 1.43) ones. Broad-bodied yearlings exceed (P>0.05) the narrow-bodied by the milk yield and fat content - by 9.8 and 10.1% respectively. The productivity factor which is higher by 0.01 (0.9%) indicates that with increase in productivity the broad-bodied cattle had no reduction in reproductive capacity. We registered a high level of differences in the reproductive capacity between the cattle of different body types; however, the difference in living weight was insignificant and was within the range of 1.0%. The first grade cattle increase the fat contamination with milk yield growth, second-grade cattle decrease the milk fat along with yield growth, and third-grade cattle increase has a stable fat contamination. The first-grade cows considered the most valuable. Their rate among the broad-bodied is 11.8%, and 11.1 among the narrow-bodied which promotes the selection of desirable body-type cattle with high productivity and fatty values. Thus, it is obvious to select the cattle with desired constitutional type, which would combine high productive and reproductive qualities.