Experimental immunotherapy of association infections of the gastrointestinal tract of newborn calves using yolk melange enriched with specific Y class immunoglobulins

Mass gastrointestinal diseases of newborn calves manifested by symptoms of diarrhea are caused by various etiological factors and most often occur in the form of mixed infections. Mixed infections have a more severe diarrhea than mono-infections. The economic consequences of such infections due to the high prevalence, frequent mortality and loss of productivity during further exploitation of the animal can be significant. The most common causative agents of gastrointestinal diseases of newborn calves of viral etiology is rotavirus and coronavirus infections. Mixed (viral-bacterial) infection can lead to 100% mortality of the diseased calves. Specific vaccination of springer cows against gastrointestinal pathogens in calves, which is performed to increase the number of pathogen-specific immunoglobulins in the colostrum at calf birth, and ingestion of colostrum by the calves during the first 4 hours of life are the most important strategies to prevent severe diarrhea. But as practice shows, this is not always enough. The purpose of this work was to study the effectiveness of immunoprophylaxis of associative infections of the gastrointestinal tract of newborn calves with the use of melange prepared from chicken eggs previously immunized with the vaccine "Rotagal" (Pharmagal-BIO s.r.o., Slovakia), used for the prevention of colibacillosis, rotavirus and coronavirus infections of cattle. As a result of the study, it was established that the addition of yolk melange rich in specific immunoglobulins of Y class to the colostrum in the first hours of life of the calves has a pronounced prophylactic effect, facilitates the course of the infectious process in case of the disease, saves costs for the treatment of sick animals, increases survival rate, contributes to the acceleration of live weight gain. The use of an immunobiological preparation based on transovarial immunoglobulins has a positive effect on the indicators of nonspecific resistance of newborn calves compared to the calves with early postnatal disease and antibiotic treatment.