Respiratorne infekcije goveda-najčešći uzroci i mogućnosti za rešavanje problema

Abstract

Bovine respiratory disease (BRD) with multifactorial etiology is permanent health problem and challenge for veterinarians. The most vulnerable group on dairy farms are calves before 4 months old and in feedlots, at the beginning of fattening period most frequently at body weight from 100 to 250 kg. Type of breeding, manipulation with animals, immunological status of cattle and exposure to pathogens have influence on morbidity and later mortality of the animals. Multifactorial etiology of respiratory diseases makes prophylactic measures very complex. This is the reason why preventive measures have to be implemented, with the aim to reduce economic loses from BRD to acceptable level for the breeders. From the veterinarian point of view the implementation of immunoprophylactic measures is very simple and effective method in suppression of BRD. In practice, vaccination of cattle is not always completely successful and this is the reason why animal owners are sometimes not satisfied with veterinary services and they often distance from them. A lot of factors have influence on unsuccessful vaccination, such as non-matching pathogen microorganisms with antigens used for immunization, animal status in period of immunization, possibility of immune response, time of immunization within the technological process of breeding etc. Research results worldwide and in our country show change in etiology, especially in viruses. During the period from 1970 to 1980, the most important viruses were bovine herpes virus 1, parainfluenza 3 and bovine diarrhea virus, later bovine respiratory sintitial virus and finally corona virus in cattle. Mycoplasma bovis is important pathogen in BRD too. Bacterial infections in lungs follow virus infections, but under specific conditions these infections alone can lead to economic loses. Therefore the use of antibiotics is necessary. Antimicrobial drugs can be used in therapeutic and in metaphylactic purposes. This is where the responsibility of veterinarians plays a very important role.