EFFICIENCY OF USING HOLSTEIN BULLS ON COWS WITH DIFFERENT LEVEL OF MILK PRODUCTIVITY

As a result of the work, the effect of the level of productivity of mothers on the results of using Holstein when crossing was studied. From first-calf cows originating from mothers with milk yield up to 3000 kg, milk is fed 33.6% less in 305 days of lactation than from first-calves received from mothers with milk yield 5000-5500 kg. The high effect of crossing black-mottled cows with Holstein bulls occurs in cows descended from mothers with lower productivity.