Use and preservation of local dairy cattle breeds (review)

Currently, the depletion of gene pools and the disappearance of farm animal breeds remain a global problem for humanity, and therefore it is necessary to ensure the conservation of biological diversity of domesticated animal species as the basis of agricultural activity. The objective of the review is to analyze scientific bibliographic domestic and foreign databases to assess the current state and number of local breeds of dairy cattle, identify problems and search for opportunities to preserve populations that are in a critical state and cause concern due to their reduction. There are reports that the preferential breeding of specialized cattle or several intra-breed lines reduces the breed and genetic diversity of the livestock, and, consequently, can lead to the complete disappearance of local cattle breeds characterized by unique valuable traits, including resistance to many diseases (O. Mwai et al., 2015; E.A. Lozada-Soto et al., 2022). The predominant use of black-and-white and red-and-white Holsteins of foreign selection in dairy herds of the Russian Federation, characterized by a weak constitution, low reproductive qualities, genetic diseases and a number of other undesirable properties, has led to a decrease in animal resistance, milk production volumes and productive use. The world practice of using one to three breeds in the selection process is unacceptable in our country due to the diversity of ecological zones, as well as differences in natural, climatic, feed, organizational and technological conditions over a vast territory (G.E. Sulimova et al., 2016; L.F. Brito et al., 2021). Currently, local breeds continue to be replaced by more economically profitable factory breeds, which significantly narrows genetic diversity. Therefore, it is necessary to preserve local breed resources (A.Kh. Abdurasulov et al., 2019; M.B. Ulimbashev et al., 2018; I.Yu. Dolmatova et al., 2011). Genetically valuable domestic cattle populations of Yakut, Istoben, Red Tambov, Tagil, Red Gorbatovskaya cattle the number of which varies from several dozen to hundreds of heads are on the verge of extinction (I.A. Paronyan, 2016). The Kostroma, Suksun, Yaroslavl, Red Steppe, Bestuzhev and Simmental breeds with livestock from several hundred to several thousand heads can be attributed to those declining in number and range (I.A. Paronyan, 2016). The problem of protecting and preserving the biodiversity of cattle breeds is also relevant in other countries. There are many breeds worldwide that produce high-quality livestock products, and their efficient use will contribute to their conservation. The significant contribution of local dairy breeds to national milk production is demonstrated by studies in India (A. Kumar et al., 2022) and Ethiopia (H. Ayalew et al., 2018). Italy is one of the few countries in the world where a significant diversity of animal breeds existed in a relatively small area. However, many of these breeds, mainly those adapted to specific environmental conditions, have been lost or are at risk of extinction. One of the disappearing dairy cattle breeds of this country is the Agerolese the uniqueness of which lies in the fact that as a result of centuries of selection, caused by an unfavorable environment and lack of pastures, animals with excellent organoleptic characteristics of milk have been bred, which are valued in the production of butter and such types of cheese as mozzarella and caciocavallo (V. Peretti et al., 2013). The process of restoring the domestic gene pool of local cattle breeds will be expectedly long and expensive, but it is necessary to prevent its irreversible loss.