In Sverdlovsk region Holsteinized black-and-white cattle of Ural type are bred. This livestock is represented by highly productive animals with a high genetic potential for productivity. The aim of the research is to study the productive qualities of the Holsteinized black-and-white cattle with a high proportion of blood relationship to Holstein breed. Milk yield increases with age of cows. The difference between the first and second lactation amounts to 1.084 kg or 11.4%, and between the second and third lactation it is 326 kg (3.0%). In general, the milk yield of mature (full-aged) cows was higher by 1.410 kg or 14.9% than the milk yield of first-calves It is known that mature full-aged cows have a productivity 30% higher than the first-calves. I. e. the genetic potential of the farm broodstock of full-aged cows is within 12.595 kg, and this potential is not fully used. The farm uses cows that are quite different in terms of milk yield. The fluctuations in milk yield from lactation to lactation are 7.060 kg (1st lactation), 10.210 kg (2nd lactation) and 6.785 kg (3rd lactation). In terms of the milk quality indicators – MFF (mass fraction of fat) and MFP (mass fraction of protein) no significant differences in lactation were established, although a certain positive tendency was observed for increase of MFF with age gaining in reference to the first-calves.
In the Sverdlovsk region, purebred bull producers of the Holstein breed of German, Danish and Canadian selection and the breeding stock of the domestic black-and-white breed of the Ural offspring were used for improvement. The Ural offspring of the black-and-white breed was distinguished by high milk yield and fat mass fraction and protein mass fraction in milk. In 2002, the Ural type of the Holstein black-and-white cattle was officially registered in the Ural region. This type has significant differences from the original rocks. The purpose of the article is to study the relationship between milk yield and milk quality indicators in cows-daughters of the Holstein black-and-white cattle of the Ural type from different Holstein bulls. It is established that the relationship of indicators depends on the belonging of cows-daughters to a particular bull producer. However, it can be noted that there is a positive relationship with an average and high level of correlation between milk yield for the first lactation and fat mass fraction in milk, milk yield for lactation and protein mass fraction in milk, and between fat mass fraction and protein mass fraction in milk in the groups of bull daughters from producers Emen and Reverse. For the group of daughters of the bull Jesmen, a high negative correlation was found between milk yield per lactation and fat mass fraction in milk, an average negative correlation between milk yield and protein mass fraction in milk, and a low positive correlation between fat mass fraction and protein mass fraction in milk. Correlation coefficients change with age. For the second lactation, the correlation coefficients differed from those established for the first lactation. So, they went to negative between milk yield and fat mass fraction in milk in the daughters of all evaluated bulls, between milk yield and protein mass fraction in milk remained the same, but decreased. The correlation coefficient between the quality indicators of milk in bull’s daughters changed to negative. Selection of cows by milk yield for the first lactation will allow you to get an increase in milk yield for full-age lactation.
The results of studying the effect of the prebiotic feed additive “Vetokislinka” on the microflora of feces, hematological parameters and the growth rate of calves of the milk period are presented. Calves of the control group received the basic diet without the inclusion of the studied prebiotic. The calves of the experimental groups were fed with the prebiotic Vetokislinka in a dose of 0.8 in addition to the basic diet; 1.0 and 1.2 ml per 1 liter of drinking water from 6-10 to 90 days of age, daily frequency, 2 times a day (50% of the daily value). According to the research results, it was found that an effective dose of the prebiotic feed additive “Vetokislinka” was a dose of 1 ml per 1 liter of drinking dose, which had a positive effect on the microbial landscape of feces in calves, in which there was a significant increase in the number of normal flora: lactobacilli and bifidobacteria, as well as a decrease in Escherichia. Within the physiological norm, the use of the prebiotic “Vetokislinka” promoted an increase in erythrocytes by 9.1%, hemoglobin by 11.3%, platelets by 15.2% compared to the first control group (p < 0.05). The average daily gain of calves was significantly higher by 9.8%, while reducing feed costs per 1 kg of live weight by 8.8%. The economic efficiency from the introduction of the prebiotic supplement “Vetokislinka” into the diet of calves, at a dose of 1 ml / head per 1 liter of drinking water, per calf was 561.6 rubles.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.