PRESERVATION AND UTILITY OF THE GENETIC FUND OF THE ROMANIAN GREY STEPPE BREED
Şt. Creangă, V. Maciuc, V.A. Bâlteanu
Researches were effectuated on 30 Romanian Grey Steppe cows raised semi-intensively, tied-up stalling, at S.C.D.C.B. Dancu, Iasi. The milk quantity per lactation ranged between 1589.64 kg (1st lactation) and 2535.43 kg in the 5th lactation also representing the maximum lactation. Starting from the 6th lactation, the milk quantity decreases and in the 8th lactation it reaches 1078.5 kg. At the same time, we identified the alleles identified for the six loci codifying the six types of major milk proteins (α S1-cz; β-cz; K-cz; β-lg; α-la; α S2-cz). A new allele a αS1-CN, called ISM, discovered in the Grey Steppe, the Moldavian variety, was fully characterized (SM index represents the Moldavian Grey Steppe).
Studies of quantitative genetics on the characteristics of milk yield of members of the Bovidae family show that both the protein content (0.63%) and the type of casein or seric proteins have a strong genetic determinism and their variants may positively or negatively influence the total protein content of milk. The main lactoprotein from milk, kappa - casein (K-cz), characterized in the specialized literature as a feature having a high degree of hereditary transmission, behaves as such in the nucleus of Romanian Grey Steppe from Dancu Iasi, Romania, a value also confirmed by the heritability coefficient (h2=0.57%).
Key words: breed, Grey Steppe, conservation, genetic fund