Ispitivanje uticaja Ornithobacterium rhinotracheale na pojavu patomorfoloških promena u respiratornim organima brojlerskih roditelja i fazana nakon veštačke infekcije

Abstract

Prvi podaci o oboljenju prouzrokovanom O. rhinotracheale datiraju iz 1991. godine kada je u južnoj Africi, Jan du Preez (Žan di Prez) otkrio novo oboljenje brojlera koje se manifestovalo blagim respiratornim simptomima. Bakteriološkim ispitivanjem organa obolelih brojlera otkrivena je gram-negativna, pleomorfna, štapiasta bakterija, sporog rasta, koja se nije mogla identifikovati kao neka od poznatih bakterijskih vrsta. Današnji naziv Ornithobacterium rhinotracheale prihvaen je 1994. godine, kada je izvršena i klasifikacija uzronika. Prema podacima iz literature infekcija O. rhinotracheale dovodi do znaajnih ekonomskih gubitaka u živinarskoj proizvodnji koji su posledica poveanog mortaliteta, suprimiranog rasta, smanjene proizvodnje jaja i odbacivanja trupova na klanici. U literaturi ima veoma malo podataka o klinikoj slici kod brojlerskih roditelja, dok podaci o patomorfološkim promenama ne postoje. Prema navodima iz literature O. rhinotracheale je izolovan iz nekoliko razliitih vrsta divljih ptica, ali nema podataka o ornitobakteriozi fazana. Zbog toga su sprovedena ispitivanja imala za cilj da se utvrdi uticaj O. rhinotracheale na razvoj patomorfoloških promena u respiratornim organima i zdravstveno stanje kokoši brojlerskih roditelja i fazana iz odgoja. Za eksperiment je odabrano 22 fazana starosti 19 nedelja i 22 kokoši brojlerskih roditelja hibrida „Ross 308“ starosti 15 nedelja. Ptice su podeljene u etiri grupe koje su držane na podnom sistemu, u odvojenim prostorijama. Nakon sedmodnevne aklimatizacije, inficirana je po jedna grupa od 16 fazana i 16 brojlerskih roditelja intratrahealnom aplikacijom suspenzije 48-asovne kulture O. rhinotracheale, soj B3263/91 u sterilnom fiziološkom rastvoru, u koncentraciji od 5 X 1011 CFU/ml. Po jedna grupa od šest fazana i šest brojlerskih roditelja služile su kao kontrolne grupe kojima je intratrahealno aplikovan po 1 ml sterilnog fiziološkog rastvora. Posle inficiranja ptice su svakodnevno opservirane i merena im je telesna masa neposredno pre inficiranja i sedam dana kasnije. Sedmog dana od inficiranja eutanazirano je po šest ptica iz inficiranih i etiri ptice iz kontrolnih grupa, intravenskom aplikacijom preparata „61“ proizvoaa Intervet. Dvanaestog dana od inficiranja eutanazirane su po etiri ptice iz inficiranih i dve ptice iz kontrolnih grupa...

The first data relating to disease caused by O. rhinotracheale originate from 1991, when Jan du Preez discovered a new disease in broiler chickens in South Africa, which manifested itself with mild respiratory symptoms. Bacteriological examination of infected birds’ organs revealed a gram-negative, pleomorphic, slow growing, rod bacterium, which could not be identified as any of the known bacterial species. The present name Ornithobacterium rhinotracheale was accapted and the agent was classified in 1994. The literature states that the O. rhinotracheale infection can cause significant economic losses in the poultry industry as a consequence of increased mortality, suppressed growth, reduced egg production and increased carcase condemnation rate at processing. There are few data about clinical features in broiler breeders nor can data about the gross lesions be found in the literature. According to the literature, O. rhinotracheale has been isolated from several different wild bird species, but there are no data relating to ornithobacteriosis in pheasants. For these reasons investigations were carried out to determine the influence of O. rhinotracheale on the development of pathomorphological lesions in the respiratory organs and on the health status of broiler breeders and pheasants from the rearing stage. A total of 22 pheasants, 19 weeks of age and 22 "Ross 308" broiler breeder hens, 15 weeks of age were used in this study. The birds were divided into four groups which were housed in a floor system, in separate rooms. After seven days of acclimatization, one group of 16 pheasants and 16 broiler breeder hens were infected intratracheally with a suspension of 48-hour culture of O. rhinotracheale strain B3263/91 in sterile saline in concentration of 5 X 1011 CFU/ml. Six pheasants and six broiler breeders served as control groups and were inoculated intratracheally with 1 ml of sterile saline per bird. After infection, the birds were observed daily and weighed at the time of infection and seven days post-inoculation. On the seventh day post-inoculation, 6 birds from infected groups, and 4 birds from control groups were euthanized by intravenous application of the euthanasia drug "T61" produced by Intervet. On the twelfth day post-inoculation, 4 birds from infected groups and two birds from control groups were euthanized. Immediately prior to euthanasia, blood samples were taken for serological examination by a puncture, from the brachial vein...