A Study on the Dynamics of the Development of Red Steppe Cows and Their Ayrshire and Holstein Crossbreeds

When purchasing animals from abroad, agricultural enterprises often underestimate their demand for feed quality and feeding standards for ensuring genetically determined milk productivity. Therefore, increasing attention should be paid to raising local breeds. During the creation of new production relations, it is very important to preserve achievements of scientists and breeders. The widespread use of red steppe cows is due to good feed payment, unpretentiousness, and their adaptability to the steppe zone with its arid climate. There was a real threat of extinction of purebred red steppe cattle: with the intensification of dairy cattle breeding, as well as low milk productivity, these animals are inferior to the best dairy breeds by productivity, but they are better by endurance, resistance to diseases, and adaptability to extreme environmental conditions. Therefore, scientific research is needed on improving the productive and technological qualities of this breed using the best global gene pool of dairy cattle. This article presents the results of a study on the development of heifers of purebred red steppe cows and their Ayrshire and red-motley Holstein crossbreeds. Differences in the live weight indicators of the purebred and crossbred heifers were due to the effect of crossbreeding and intensive growing technology, which made it possible to maximize the genetic potential of the crossbred animals. Keywords: breed, steppe red, Holstein, Ayrshire, live weight, feed costs, die

Advanced liver disease in Russian children and adolescents with chronic hepatitis C.

Russia has one of the highest prevalences of paediatric chronic hepatitis C infection (CHC). Our aim was to provide a detailed characterization of children and adolescents with CHC including treatment outcomes. Thus, an observational study of children with CHC aged <18 years was conducted in three hepatology centres from November 2014 to May 2017. Of 301 children (52% male), 196 (65%) acquired HCV vertically, 70 (23%) had a history of blood transfusion or invasive procedures, 1 injecting drug use and 34 (11%) had no known risk factors. Median age at HCV diagnosis was 3.1 [interquartile range, IQR 1.1, 8.2] and 10.8 [7.4, 14.7] at last follow-up. The most common genotype was 1b (51%), followed by 3 (37%). Over a quarter of patients (84, 28%) had raised liver transaminases. Of 92 with liver biopsy, 38 (41%) had bridging fibrosis (median age 10.4 [7.1, 14.1]). Of 223 evaluated by transient elastography, 67 (30%) had liver stiffness ≥5.0 kPa. For each year, increase in age mean stiffness increased by 0.09 kPa (95% CI 0.05, 0.13, P < 0.001). There was significant correlation between liver stiffness and biopsy results (Tau-b = 0.29, P = 0.042). Of 205 treated with IFN-based regimens, 100 (49%) had SVR24. Most children (191, 93%) experienced adverse reactions, leading to treatment discontinuation in 6 (3%). In conclusion, a third of children acquired HCV via nonvertical routes and a substantial proportion of those with liver biopsy had advanced liver disease. Only half of children achieved SVR24 with IFN-based regimens highlighting the need for more effective and better-tolerated treatments with direct-acting antivirals. Further studies are warranted in Russia on causes and prevention of nonvertical transmission of HCV in children