Evaluation of bulls-producers for the manifestation of the paired signs of their daughters

UDC 636.2.082.034

S. Bondar

As a result of reseach it was determined that cows-daughters from different bulls-sires are distinguished by the level of milk productivity.
Among the evaluated bulls of Holstein breed the highest indicators of milk productivity were characterized in daughters of K. Delko Red 3615945. Difference by the quantity in milk yield comparing with daughters of bull Marselin Et 538 was 2027 kg (P>0,95) but yield them in the content of fat in milk.
On the high development of milking in sires of milking in sires of bull K. Delko Red 3615945 the «A» is also testified. At the same time it should be noted some lowering the coefficient of reproductive ability in cows-daughters with high level of milking. It is indicated to violation in their reproductive ability. The difference between comparing groups of the investigative animals was 0,01; 0,04; 0,06 and 0,03 accordingly.
As a result of the analysis of the group structure of daughters by «A» and KBZ and their peculiarities it was determined the breed value of bulls-sires that were used for improving dairy cattle of the Ukranian selection. From the bull K. Delko Red 3615945 it was obrained more daughters which unite high indicators of productivity and reproductive abilities and form group «1-1», their specific weight was 58,3 %. However the data ot the specific weight of cows in thee groups: (2-1)+(1-1)+(1-2) were only 66,6 per cent and therefone by the quantity of marks it was appropriated the second category of the breed value to this sire. This is explained not only by the significant quantity of cows-daughters which were in the group «1-2» and «2-1», only 8,3 percent and available sires with low indicators of milking and reproductive abilities – it is the structure «2-2» (33,4 %). By reason o of evaluation displaying of combined peculiarities in daughters the first category of breed  value was fixed for three bulls.
Thus by the results of research it was fixed that using bulls-sires of Holstein breed determines different level of milk productivity and reproductive ability in cows-daughters. By the breed value the advantage have these sires which cause the high level of display linked features in off springs.

Key words: bulls-producers, cows, milk productivity, reproductive ability, paired signs, pedigree value.

Evaluation of bulls-producers for the manifestation of the paired signs of their daughters.