PREVENTIVE EFFICACY OF SEROIZATISON AGAINST VIRAL RESPIRATORY DISEASES OF CALVES

The main goal of the research was to study preventive activity of Seroizatison complex preparation against certain viruses appearing in etiology of mixed respiratory diseases observed among calves at farms of the Republic of Dagestan. Efficacy tests of the preparation and dosage schemes development were carried out at cattle farms with unfavorable respiratory disease background. The study was focused on Seroizatison complex preparation consisting of immune serum and Izatison mixed in 85 ml to 15 ml ratio respectively. Convalescent blood serum from cattle or polyvalent hyperimmune serum against infectious bovine rhinotracheitis (IRT), parainfluenza-3 (PG-3), bovine viral diarrhea virus (VD-BS), and bovine adenovirus infection (ADVI) obtained from hyperimmuned stud bulls of 1.6 - 2 years old was used as immune serum in the tests. Testing Izatison for effective concentration showed that 15% concentration of Izatison in the complex preparation had the maximum preventive efficacy. Preventive efficacy of Seroizatison with 15% concentration of Izatison was by 14.8% higher in the test group of calves than in the control group. Tests carried out on calves deliberately infected with virulent viral strains showed that introduction of Seroizatison 24 hours before infecting the calves with IRT, PG-3, and bovine ADV prevented development of clinical signs of respiratory diseases in all animals. The best preventive efficacy was observed in the group of calves treated with Seroizatison preparation, 97.5%; treatment with Izatison preparation in combination with Aethonium, convalescent serum, and hyperimmune serum returned 82.5%, 82.5%, and 85.0% preventive efficacy respectively. Introduction of hyperimmune serum into the Seroizatison composition enhances preventive efficacy of the complex preparation against respiratory diseases in calves by 15% compared to Izatison.