Clinical and pathomorphological diagnostics of mycotoxicosis in parent poultry flock caused by T-2 trychotecene

Abstract

The most relevant mycotoxin from the trychotecene group, T-2, causes prominent citotoxic effects. The toxin is a secondary product of fungi from the genus Fusarium that contaminates feed. Oraly intaken, T-2 is absorbed fast in the upper digestive system and within only 3 to 4 hours later reaches liver, kidneys and muscle tissue. Clinical and pathological changes are sometimes not obvious. The case of mycotoxicosis in a breeder flock of chickens, here presented, is aimed to underline the significance of clinical and pathological diagnosis supported with laboratory analysis that gave an objective causative diagnosis. On the farm, the disease occurred suddenly and with total cessation of feed consumption. First cases were recorded in the flock at the age of 42 weeks. Grouping, intensive breathing and lying with overstretched legs and extended neck were symptoms observed in birds. Evident necrosis of beak tips and painful multi-focal necrosis in oral cavity were recorded during the clinical examination. On section, dark unclothed blood was first observed. Other postmortem findings included: filled gizzard with mucosal erosions and easy-removable cuticle, enlarged congested liver with multi-focal necrosis and subcapsulary bleeding. The mortality rate increased by 4%, and the drop of laying rate was by about 18%. The fertility rate decreased by 22%. There was the increased number of rejected hatching eggs, 12%. Culture of the complete diet resulted in approximately 150000 colonies per 1g of Fusarium. T-2 was detected by using ELISA in concentration of 480 μg/kg, which corresponded to the upper limit of maximum permitted concentrations for chickens, according to national legislations. This bylaw interpretation of “tolerable” concentrations of mycotoxins provokes controversy among experts and public. [Projekat Ministarstva nauke Republike Srbije, br. TR 31071]

Keywords

• clinical and pathological diagnostics
• poultry
• mycotoxins
• T-2
• legislative