Comparative characteristics of the sensitivity of the bird to aspergillosis pathogens

Abstract

It has been established that the most common mycoses among poultry are aspergillosis and mucormycosis, which are observed in sporadic cases under conditions of violation of egg incubation technologies, zoohygienic conditions for poultry keeping, and feed storage. Aspergillosis (pneumomycosis, brood pneumonia, mycosis) is an infectious disease that most often affects the respiratory system and, less often, the serous membranes of other organs, namely the liver, intestines, spleen, kidneys, central nervous system, and air cavities of the tubular bones. Aspergillosis affects all species of poultry and wild birds. The disease is more common in young animals in the first days of life. In the studied poultry farms, aspergillosis has a different intensity. The disease can kill 30 to 50 % of all young animals and, in some cases, only a few. This is due to the infection of the fungus in the environment, its pathogenicity, the bird's age, and its resistance. The material for the research was carcasses and aspergillosis-sick birds from Poltava HPE LLC, Poltava Poultry Factory JSC, Poltava Incubator Agricultural Complex, and Poltava district private farms. Statistical indicators from the surveyed farms and micro-sections. It has been established that the causative agent of aspergillosis in chickens and young guinea fowl is mainly the fungus Aspergillus fiimigatus, less often Aspergillus flavus. Sources of infection in the surveyed farms are infected hatching eggs infected with fungal spores and moldy litter. Determining factors contributing to the infection are unsatisfactory conditions for keeping young birds: high humidity and faulty ventilation system. Chickens are more sensitive to aspergillosis than young guinea fowl because, for chickens, the number of detected pathologies in various organs and systems is much higher. The disease in chickens is superacute, acute, and chronic; in young guinea fowl, it is in a mild form (without chronic forms). Clinical signs of avian aspergillosis are not typical, which complicates the lifelong diagnosis of the disease. The results show that raising guinea fowl is a more profitable business because the rate of loss of young is much lower than that of chickens and the rate of sexual maturity for guinea fowl is also higher. Aspergillosis in one-three-day-old chickens is characterized by serous tracheitis, bronchitis, aerosacculitis, and serous fungal pneumonia. Histological examination of the lungs showed swelling of endothelial and alveolar cells, the presence of fungal spores in blood vessels, necrosis, and desquamation of the respiratory epithelium.