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In modern breeding work, considerable attention is paid to genetic resources of cattle, genetic assessment of which, with proper crossbreeding and selection, can increase efficiency of the entire industry. One way to realize the genetic resources of animals is to use information about polymorphism of milk productivity genes. The aim of the study was to determine polymorphism of -lactoglobulin gene in in Kholmogorsky cows and to identify its effect on economically valuable milk indicators. The experiments were carried out on the breeding stock of Kholmogorsky breed in Kholmogorsky Plemzavod. The genotype of the studied animals for LGB gene was determined by PCR RFLP using Hae III restriction endonuclease. It was established that the allele B of the -lactoglobulin gene was dominant in the genome of the studied sample of cows and its frequency of occurrence was 68%, while the most common genotype was AB (47.4%). To assess the effect of different LGB genotypes on milk productivity and milk quality of Kholmogorsky cows, productivity indicators for the last completed lactation were combined into subgroups depending on the genotypes and compared with each other. Most likely, the uniqueness of the Kholmogorsky breed, expressed not only in terms of milk productivity, exterior and constitution, but also in the gene pool, influenced the discrepancy between the obtained results and general patterns. Firstly, in our case, B allele has a positive effect both on qualitative and technological characteristics of milk, and on quantitative indicators of milk productivity. Secondly, the largest value of milk yield and the mass fraction of dry matter belongs to animals with the AB genotype. We recommended to include the procedure for assessing polymorphism of LGB gene in a set of breeding and production work activities to increase the economic efficiency of the enterprise. Such a step will also contribute to the further comprehensive study of this gene as a breeding marker.

The article discusses the dairy industry in the Chuvash Republic, Russia. The Russian Federation is experiencing a shortage of milk. Currently, the per capita milk consumption in the country is by more than a quarter behind the rational intake recommended by the Ministry of Health, which is 325 kg. However, the Chuvash Republic boasts 373 kg of per capita milk production, which is by 71% higher than the average data for the rest of the country, and the high quality of Chuvash milk is unanimously confirmed by leading domestic experts. The authors analyzed the success factors of milk production in the Chuvash Republic to be extrapolated on the entire domestic industry. The research relied on such demographic data as the ratio of urban vs. rural population; dairy herd data, e.g., livestock population, farm types, dairy productivity, etc.; dairy production and processing business data. The methods included systematization, generalization, grouping, statistical data processing, and analysis of temporal dynamics indicators. The Chuvash Republic has a large percentage of rural population and a lot of subsidiary dairy farms: 22 000 farms own more than 60% of dairy cows in the region and provide 55% of milk processing volumes. Subsidies allocated by the local government allow farm owners to ensure the high dairy productivity of cows. Most of the milk in the Chuvash Republic can be classified as near-organic. Leading regional milk producers have their own agricultural lands to provide environmentally friendly feed, as well as specialized premises for herd keeping and milking, retail outlets to sell their products, etc. A third of enterprises maintain the milk productivity at 7800–9200 kg, which is as high as in Denmark, the Netherlands, Great Britain, and Germany. Most Chuvash dairy farmers owe their high results to the state support funds allocated for the purchase of breeding cattle. The twelve largest milk producers in the region provide 100% of the output of drinking milk, so private farms mainly focus on meeting the needs of dairy processing enterprises. The latter also receive seasonal subsidies. The Chuvash milk miracle can be explained by the following factors: big rural population; private subsidiary farms; high-quality breeding dairy livestock; high-quality feed; good milk production and processing equipment. However, the comprehensive system of state support measures remains the most important success factor.

The cryopreservation of gametes and embryos is an important element of biodiversity conservation. One species in need of conservation is the honey bee Apis mellifera L. Changing environmental factors, especially the anthropogenic factor, have led to a reduction in the numbers of this insect species. In this study, we provide an example of the creation of a biobank of honey bee drone sperm. For sperm cryopreservation, drones of the most common subspecies of honey bees common in Russia were selected. These were the dark forest bee, Apis mellifera mellifera, from the Republic of Bashkortostan, with three subspecies (A. m. carnica, A. m. carpatica, and A. m. caucasica) from the southern regions of Russia, as well as two breeding stocks, the Far Eastern bee and Prioksky bee. For subspecies identification, morphometric and genetic methods were used. The subspecies of the studied samples were confirmed via the analysis of the tRNAleu-COII locus of mitochondrial DNA and nine microsatellite markers of nuclear DNA. It was shown that bees of the Prioksky breeding stock belong to the subspecies A. m. caucasica based on phylogenetic analysis, and the Far Eastern breeding stock is a stable hybrid, descending on the maternal line from the evolutionary lineage C or O. The results of the morphometric analysis are consistent with the results of the genetic analysis. For the cryopreservation of sperm, we used a cryoprotectant solution with honey. As a result, the viability of frozen–thawed sperm decreased by 20.3% compared to fresh sperm, and overall motility decreased 25-fold. The measurement of the sperm concentration in the spermatheca of artificially inseminated queens showed that it varied from 0.22 to 4.4 million/μL. Therefore, the use of honey in sperm cryopreservation has great potential.

To promote persimmon breeding project, we analyzed the sugar composition (a ratio of sucrose to hexose sugars, SH ratio) and flesh juiciness of 43 persimmon cultivars (Diospyros kaki Thunb.) consisting of 24 pollination-constant non-astringent (PCNA)-types and 19 non-PCNA-types, together with other fruit quality traits. The cultivar collection includes newly-released cultivars after 1990 and commercially-produced local cultivars in Japan. These cultivars were broadly classified into three types: sucrose accumulators, intermediate accumulators, hexose accumulators. Analysis of variance showed that the genotypic effect on the SH ratio and flesh juiciness is high with negligibly small environmental variance, indicating that SH ratio and flesh juiciness can be determined by a one-year trial without tree replication. Highly varietal diversity in the SH ratio and flesh juiciness was observed within and between persimmon cultivar types. Sweetness value (SSC × SH ratio) of the cultivars/selections seems to be a useful predictor of fruit sweetness. In terms of palatability, however, persimmon cultivar’s improvement should be performed on the sweetness value in association with flesh juiciness.