R. R. Shaydullin, G. S. Sharafutdinov, A. B. Moskvicheva
Kazan State Agrarian University, ul. K. Marksa, 65, Kazan’, 420015, Russian Federation
Abstract. The paper studies change in protein content in the milk of first-calf heifers of different kappa-casein (CSN3) and diacylglycerol O-acyltransferase (DGAT1) genotypes during lactation. The work was performed in 2013–2015 on 142 first-calf heifers of Black-and-White breed in the Republic of Tatarstan. In the DNA test we used venous blood. Lactation performance was studied individually according to the results of monthly control milkings. The mass fraction of protein in milk was determined 3 times. The protein content decreased at the beginning of lactation and increased by its end (10th month). The cows of CSN3(AA) genotype showed a decrease during the 1st month of lactation (3.04%); the cows of CSN3(AB) genotype – during the 2nd month (3.08%); the cows in CSN3(BB) groups – during the 3rd month (3.19%); the cows of DGAT1(AA) and DGAT1(AK) genotypes – during the 1st month (3.05% and 3.06% respectively), the cows of DGAT1(KK) genotype – during the 4th month of lactation (3.12%). Throughout the lactation, the mass fraction of protein in the milk of the heifers of CSN3(BB) genotype (3.19–3.40%) was significantly higher – by 0.09–0.17%, in the milk of the heifers of DGAT1(KK) genotype (3.12–3.29%) it was higher by 0.04–0.12%. The highest yield of milk protein was observed in the cases of CSN3(BB) and DGAT1(AK) genotypes. It was the highest during the 3rd, 8th and 9th months of lactation for CSN3(BB) genotype and from 5th to 9th months for DGAT1(KK) genotype. High protein content in the milk during the whole lactation was typical for animals with complex CSN3(BB)/DGAT1(AK) (3.21–3.42%) and CSN3(BB)/DGAT1(AA) (3.15–3.36%) genotypes with significant superiority over the peers of other genotypes, respectively, by 0.07–0.24% and 0.07–0.16%. The first-calf heifers having in their genotype B allele of CSN3 gene and K allele of DGAT1 gene were most often characterized by higher content and output of milk protein during lactation compared to the animals having A allele of CSN3 and DGAT1 genes in their genome.
Keywords: genotype; gene; CSN3; DGAT1; cows; protein; milk; protein content in milk; lactation.
Author Details: R. R. Shaydullin, D. Sc. (Agr.), head of department (е-mail: Этот адрес электронной почты защищён от спам-ботов. У вас должен быть включен JavaScript для просмотра.); G. S. Sharafutdinov, D. Sc. (Agr.), prof.; A. B. Moskvicheva, Cand. Sc. (Agr.), assoc. prof.
For citation: Shaydullin R. R., Sharafutdinov G. S., Moskvicheva A. B. Protein Content in the Milk of First-Calf Heifers of Different CSN3 and DGAT1 Genotypes during Lactation. Dostizheniya nauki i tekhniki APK. 2019. Vol. 33. No. 5. Pp. 55–58 (in Russ.). DOI: 10.24411/0235-2451-2019-10513.