Reproductive and adaptation qualities of Canadian breeding hogs commercially reared in Lower Volga region

Purchase of foreign genetic material, including Canadian Yorkshire, Landrace and Duroc pigs, in order to increase the productivity of dpmestic pig breeds has recently been a steady trend in Russia. The adaptive ability of pigs is the most important feature determining their availability for industrial growing technology. The purpose of our work was to study the adaptiveness and performance of purebred Yorkshire, Landrace and Duroc pigs of Canadian selection under the conditions of OAO Cossack Holding Krasnodonskoe (Ilovlinskii Region, Volgograd Province), a large regional commercial farm for growing and fattening pigs. The study was carried out in 2013-2014. In assessing natural resistance, the auto microflora of deep skin layers was estimated. The number of erythrocytes, leukocytes, the percentage of leukocytes, the phagocytic index, total blood proteins, protein fractions, and the concentration of immunoglobulins (Ig) G-, M- and A-isotypes in blood serum were also determined as parameters of natural resistance. The reproductive performance of pigs was assessed according to the data of evaluation and livestock records. On fattening, the early maturity, overall, average per day and relative live weight gain were recorded. Sperm production in boar-producers was estimated using conventional methods, based on the volume of ejaculate and sperm concentration and motility. The economic efficiency of different pig breeds was assessed on the basis of analysis of actual and on-farm annual activities. In 2014, the analysis of populations of different breeds showed that there were 832 Yorkshire breeding sows, 50 Landrace breeding sows and 58 Duroc breeding sows. The Yorkshire sows produced 2028 piglets, their livability by weaning reached 90.83 %; for the Landrace breed, there were 85 piglets and 85.88 %, respectively (4.95 % less compared to that in Yorkshire piglets), and for the Duroc breed, these figures were 88 and 85.30 % (5.53 % less compared to that in Yorkshire piglets). Among the five families of the Yorkshire sows, the largest part of the population belonged to the families of Volga (42.17 %), Soya (17.07 %) and Oka (15.86 %). The Landrace breed sows herd was concentrated in the families of Loga (23.81 %) and Luna (23.81 %). The greatest part of the Duroc sows was related to Dakota (28.00 %) and Dama (28.00 %) families. The Yorkshire boars had a fat thickness above 6-7th thoracic vertebrae equal to 14.8 mm, which was 6.61 % less compared to the Landrace breed, and 5.40 % less compared to Duroc breed. The prolificacy of Yorkshire boars was 12.16 heads, which was 0.23 and 1.46 heads more than in Landrace and Duroc breeds, respectively. In assessing the exterior indices, the Yorkshire boars were superior to the boars of Landrace and Duroc breeds by 0.33 and 0.20 points, respectively. The natural resistance characteristics have shown a higher potential for adaptability of the Yorkshire breed to new climatic conditions and technologies. Calculation of economic efficiency of pork production has shown that the income for the Yorkshire piglet sale by live weight was 1,520 and 10,640 rubles higher compared to that for the Landrace and Duroc piglets, and the profitability was 0.86 and 4.99 % higher, respectively; for the carcasses the income exceeding amounted to 0.92 and 5.30 %, respectively.