Analysis of the use of industrial crossbreeding to improve the profitability of the pig industry

The aim of the research was to conduct an economic assessment of the use of industrial crossbreeding in the pig industry. The study was carried out in LLC "Mayak-Agro" (Ukraine) and in the laboratories of the Cherkasy National University named after Bohdan Khmelnitsky and the Cherkasy Experimental Station of Bioresources of the National Academy of Sciences of Ukraine. Ukrainian breeds of pigs were used: (Ukrainian BigWhite-1 (UBW-1), Red White-Belt (RWB) and Duroc of the Ukrainian selection "Steppe" (DUSS)). Breeds of English origin: (Big White (EBW), Landrace (L), Pietrain (P)). Crossbreeds, obtained by crossing the breeds, mentioned above. A comprehensive assessment of the reproductive capacity of a sow was carried out taking into account multiple births, the number of piglets at one month of age and the average daily gain during this period. Growth and development were monitored in terms of changes in live weight by individual weighing at birth and every month to a live weight of 100 and 120 kg. Regardless of maternal form, in the groups where boars of the breeds Red White-Belt and Pietrain were used, higher indicators of comprehensive assessment of reproductive capacity were obtained. The best fattening qualities characterized piglets, obtained from a combination of sows (1/2UBW-1+1/2L) with boars of the Pietrain breed (P). In comparison with other variants of crosses, in this group the animals reached a live weight of 100 kg 7.6 days earlier. Their feed costs per 1 kg of live weight gain were 3.33 feed units, which corresponds to the expected figure of 3.34 feed units when fattening up to 100 kg in 170 days. In terms of industrial pork production, breeding of animals of the group (1/4UBW-1+1/4L+1/2P) was more profitable, in which the highest level of profitability was obtained - 22.3 % for fattening up to 100 kg and 12.5 % for fattening up to 120 kg. Cultivation of three-breed hybrids to a live weight of over 100 kg led to a decrease in profitability among all research groups. The use of the genotype 1/4UBW-1+1/4L+1/2P in industrial production makes it possible to obtain animals of various weight conditions without significant additional costs and profitability level reduction. In the course of the research, it was found, that the best option for three-breed crossing is the use of boars of the Pietrain and Red White-Belt breeds. The use of boars of these breeds is ideal for producers looking for bacon pork. The use of boars of the Duroc breed of the Ukrainian selection "Steppe" (DUSS) makes it possible to obtain fatty pork with the possibility of fattening to different weight categories

Effects of Environmental Factors on Reproduction of the Sea Urchin Strongylocentrotus Intermedius

The results of long-term studies (2003–2015) of the reproductive biology of the sea urchin Strongylocentrotus intermedius in wild populations located in the northwestern Sea of Japan along 400 km of the coast of the Primorye region of Russia and differing by the level of anthropogenic pressure are reported. Our analysis showed that since 1970–1980s, the shift in spawning season from autumn to early summer occurred in S. intermedius populations inhabiting anthropogenically polluted areas of Peter the Great Bay, resulting in the appearance of three types of populations that differ from each other in the proportions of individuals with early spawning (the end of May–June) and late spawning (September–early October). Our results indicate that neither photoperiod nor temperature may be considered as the primary external factors determining a shift in S. intermedius temporal patterns of gonad maturation and the timing of spawning and that phytoplankton concentration is the main factor for initiation of sea urchin spawning activity. We hypothesized that the shift in spawning season from autumn to early summer in S. intermedius populations inhabiting polluted areas can be explained by a phenotypic response of this species to environmental changes caused by chronic eutrophication