The analysis of the condition of colostral immunity of sows after vaccination against porcine epidemic diarrhea virus

Abstract

Porcine epidemic diarrhea (PED) is an acute, highly contagious viral disease of pigs of all age groups, but it is manifested by particularly high mortality of newborn piglets and characterized by vomiting, diarrhea, and lack of appetite. Porcine epidemic diarrhea (PED) remains a problem for pig farms in many countries, including Ukraine. Specific prophylaxis PED had proven to be a difficult task and despite many studies, the problem of PED remains unresolved. Since piglets get infected during the first days after birth, their protection can only be provided by colostral antibodies of immuned sows. Therefore, the urgent task of veterinary medicine scientists is to develop effective methods of preventing the disease, which is to use local strains of the pathogen. The article presents the results of studies of colostral immunity of piglets by determining the presence of antibodies against the PED virus in the colostrum of sows who were immunized with a vaccine inactivated against PED from the intestinal virus of artificially infected suckling piglets. Infectious activity of matrix broods of the virus for the production of the preparation was determined by RT-PCR. According to the results of research, material was selected for the manufacture of the vaccine. Subsequently, the drug was monitored according to technological regulations, including the infectious activity of the virus, which ranged from 1.96×10–8 to 3.16×10–9. We conducted a comparative study of the presence of antibodies to the PED virus in the colostrum of sows in the treatment of animals by “back-feeding” and vaccination of sows with inactivated preparation. Samples of colostrum from sows were taken within 1–4 hours after farrowing. The article presents research results that allow us to conclude that both methods of treatment of sows create immunity in newborn piglets. Thus, the presence of antibodies to the PED virus in colostrum in the first hours after birth provide protection against infection and death.