SELECTION IN DAIRY CATTLE
SELECTION IN DAIRY CATTLE
Gayane Mkrtchyan
Candidate of Agricultural Sciences, Associate Professor of the Department of Genetics and Animal Breeding named after V.F. Beauty in FGBOU VO MGAVMiB-MVA named after K.I. Skryabin,
Russia, Moscow
Ferdaus Bakai
Candidate of Biological Sciences, Associate Professor of the Department of Genetics and Animal Breeding named after V.F. Beauty in FGBOU VO MGAVMiB-MVA named after K.I. Skryabin,
Russia, Moscow
ABSTRACT
In the practice of animal husbandry, use and breeding animals have long been distinguished. Accordingly, the division of farms into commodity and breeding was established. Breeding includes animals that have a known origin, reliable data on productivity and breeding value recorded in stud books. From a genetic point of view, all animals used for breeding should be considered breeding because their breeding value is determined by the additive genotype and because the progress of any breed depends on changes in its genotypic structure due to mutations and recombinations of genes, selection pressure on all individuals of this breed. [1,3]
Keywords: selection, animal husbandry, milk, cattle breeding.
It is more reasonable to consider all animals used for breeding as breeding, not only because the additive genotype is created in all possible mating combinations, but also because it is economically beneficial. In the country as a whole, the share of cows in breeding farms accounts for 2% of the total number of cows in collective farms and state farms, and the share of milk production is 2.6%. [ 2,4]. Obviously, providing the population with milk and dairy products depends almost entirely on the quality of the animals used. Therefore, their improvement is of paramount importance. It should be noted that significant progress has been made in the qualitative transformation of dairy cattle by crossing. However, crossbreeding alone cannot ensure further progress and productivity. It is feared that this method appears as the only way to create highly productive dairy cattle. Meanwhile, the Holstein-Friesian breed, outstanding in terms of milk production, was improved by “pure” breeding. Zootechnical science has developed a coherent theory of breeding work, which ensures the continuous evolution and progress of breeds. [1,4]. The central link in breeding work is the selection of animals, in particular the selection for breeding value. However, in fact, the selection of animals is not carried out intensively enough and is not controlled even in breeding farms. Moreover, in a number of cases, the plans set such tasks that make any selection impossible. So, in stud farms in our time, a long-term plan for breeding work provides for increasing the number of cows of the black-and-white breed in 10 years by more than 2 times. By itself, this problem can be solved, but it will not allow selecting cows either by origin, or by their own productivity, and even more so by breeding value, since all breeding stock will be involved in the breeding process. The situation is no better with the selection of bulls. Other activities related to the assessment and intensity of selection of producers are not specified and are not supported by any genetic selection justifications[2,3]. If we take into account that 10 lines of Black-and-White cattle are bred and that it is desirable to have at least four branches in each line, each of which must be represented by four bulls, then the total number of main bulls will be 160. Therefore, it will be necessary to introduce annually into herd of producers 32 bulls, checked for the quality of offspring. As can be seen, the plan for obtaining bulls for repair does not provide the possibility of their selection according to the quality of the offspring.
In dairy cattle breeding, a lot of work is being done on breeding records. However, origin information. productivity, and in some cases, breeding value are not always used for selection purposes (the results of the assessment do not end with selection). In such a situation, the breeds find themselves in the position of a freely interbreeding population experiencing spontaneous, as well as purposeful selection pressure. As a result, breed progress may slow down or even stop.
Intensive selection of animals, based on the evolutionary theory of Charles Darwin, unfortunately, has not yet become a universally functioning method of continuous improvement of dairy cattle. In order to put the theory of selection at the service of the national economy, it is necessary to cover the following, in our opinion, the most important sections of breeding work with obligatory planning and reporting.
1. Selection of animals according to their own productivity in all commercial and breeding farms.
2. Selection of animals according to the quality of offspring at breeding farms, artificial insemination stations, breeding farms (primarily for obtaining high-value bulls), in all categories of farms and enterprises (for the predominant use of improver bulls).
3. Selection of animals by origin in all breeding farms. and breeding enterprises to create and maintain the structure of breeds and ensure intrabreed heterosis.
All these sections of the selection program from a biological point of view represent a single whole of the implementation of the theory of artificial selection. At the same time, to a certain extent, they will be isolated by the place and scale of their implementation, as well as differences in the time of achieving the selection effect. Thus, the first section of the program will give a selection effect in the very first year of implementation. The second and third sections will begin to give returns on meat production in 2-3 years and on milk production in 3-5 years.
To the theory of selection! has become a productive force, it is necessary that its main provisions become known not only to breeders, but to all managers of agricultural production. It is also necessary that the main parameters of the breeding process be included in the state plan.
What is necessary for the implementation of the program of selection of animals for their own productivity in dairy cattle breeding? One of the decisive conditions for the implementation of selection is the reproduction of animals. Obviously, for this it is necessary to have more descendants than it is necessary to replace parental individuals. If there are as many descendants as needed to replace the parents, then evolution by selection cannot occur. If there are fewer descendants, then the population will be doomed to extinction.
Figure 1. Receiving and using heifers
According to Figure 1, it can be seen that with an average of 2013 to 2015.Only 23.2% calved, received heifers for the reporting period from 2011 to 2015, an average of 42%. All first-calf heifers without selection are transferred to the main herd to ensure the replacement of retired cows and the increase in the number of dairy herds.
In nature, there is not a single species of animal that produces only one offspring per parent. How is this main condition of evolution used in the selection of farm animals according to their own productivity.
References:
- Basonova O.A. Milk productivity of Holsteinized black-and-white cattle / Basonova O.A., Vorobieva N.V., Taygunov M.E. // Zootechnics. - No. 2010. - No. 7. - P.15-18.
- Voronina, E. The influence of cow selection options on their milk productivity / Voronina E., Strekozov N., Abrampalsky F. Abylkasymov D. // Dairy and beef cattle breeding. - 2007. - No. 4. - P.8-9.
- Sipachev S.G. Selection in Dairy Cattle Breeding / Sipachev S.G.// Animal Husbandry
- Nazarchenko, O.V. Breeding and genetic parameters of economic and biological characteristics of the Black-and-White breed of various ecogenesis in the Trans-Urals. Monograph. Kurgan, 2012. - 220 p