Key Blood Enzymes as a Sign of Dairy Cattle Selective Breeding
The effectiveness of interior-complementary selection of cows by the level of serum enzymes has been revealed. In contrast to traditional selection, the more criteria are taken into account during selection, the more effective it is. When selecting first-calf heifers for one of the enzymes, the difference in milk yield is up to 446 kg of milk, with the total selection for the concentration of serum enzymes, it consistently increases to 656, 1059 and 1228 kg of milk. The same pattern is also characteristic when comparing hereditarily similar animals. In heifers at an early age, the level of the enzyme AST in the blood serum can be successfully predicted productivity in the adult state. The terms of use of productive animals directly depend on the level of transaminase concentration in young animals aged 9‒12 months. A new classification of performance types has been formulated, as well as an analysis of the nature of inheritance of milk productivity in the interior-complementary selection of animals has been given
Key Blood Enzymes as a Sign of Dairy Cattle Selective Breeding
The effectiveness of interior-complementary selection of cows by the level of serum enzymes has been revealed. In contrast to traditional selection, the more criteria are taken into account during selection, the more effective it is. When selecting first-calf heifers for one of the enzymes, the difference in milk yield is up to 446 kg of milk, with the total selection for the concentration of serum enzymes, it consistently increases to 656, 1059 and 1228 kg of milk. The same pattern is also characteristic when comparing hereditarily similar animals. In heifers at an early age, the level of the enzyme AST in the blood serum can be successfully predicted productivity in the adult state. The terms of use of productive animals directly depend on the level of transaminase concentration in young animals aged 9‒12 months. A new classification of performance types has been formulated, as well as an analysis of the nature of inheritance of milk productivity in the interior-complementary selection of animals has been given
Ethological individuality as a sign of ayrshire cattle breeding
Studies having been carried out on animals of Ayrshire breed show that indexes of food, motion and total activity selection can be successfully used as selection signs. Selection of cows on ethological individuality is accompanied by an increase of their milk production. Animals with increased food activity, compared to cows with a low one, have got the rise of milk yield per lactation by 686 kg. Ultra-active cows should be mentioned particularly, productivity of them opposite to infrapassive ones increases by 49%.
Ethological individuality as a sign of ayrshire cattle breeding
Studies having been carried out on animals of Ayrshire breed show that indexes of food, motion and total activity selection can be successfully used as selection signs. Selection of cows on ethological individuality is accompanied by an increase of their milk production. Animals with increased food activity, compared to cows with a low one, have got the rise of milk yield per lactation by 686 kg. Ultra-active cows should be mentioned particularly, productivity of them opposite to infrapassive ones increases by 49%.
Use of ethological indices in ayrshire cattle breeding
The article presents data of ethological monitoring of Ayrshire first lactation cows, which are kept in tied confinement during summer. Breeding cows according to the ethological individuality is accompanied by an increase of milk productivity indicators. Animals with high feeding activity have a 967 kg increase per lactation, compared with animals with low feeding activity. The productivity of active and ultra active cows increases by 15.6 -17,2 %, while the coefficient of lactation stability increases by 5 - 9 %, unlike the productivity of infrapassive animals.
Use of ethological indices in ayrshire cattle breeding
The article presents data of ethological monitoring of Ayrshire first lactation cows, which are kept in tied confinement during summer. Breeding cows according to the ethological individuality is accompanied by an increase of milk productivity indicators. Animals with high feeding activity have a 967 kg increase per lactation, compared with animals with low feeding activity. The productivity of active and ultra active cows increases by 15.6 -17,2 %, while the coefficient of lactation stability increases by 5 - 9 %, unlike the productivity of infrapassive animals.
