Avaliação renal e hepática de poedeiras comerciais em pico de produção alimentadas com dietas contendo subdoses de micotoxinas

Abstract

Grains play an important role in the production system as a basic ingredient in animal diets. Due to crop interferences, grains handling failures in the field and mainly their inadequate storage, they provide vulnerability of these grains to the action of fungi. The impacts caused by fungi within the production chain lead to low profitability of animal production due to the lower quality and productivity of the raw material. The mycotoxins that are most commonly related to the impact on the poultry production system are T2 toxins, fumonisins and aflatoxins. Considering the importance of the quality of raw material supplied to birds and the existence of few studies carried out with commercial laying hens, in addition to the absence of analysis of the dynamics of triggering mycotoxicosis for a prolonged period, this study aimed to study the cumulative and synergistic effect of mycotoxins in laying hens for a period of 32 to 68 weeks of age, during the peak production phase. For this, in a commercial laying hen farm in the Agreste region of the state of Pernambuco, samples of the manufactured rations were collected and analyzed using the immunochromatography technique to detect trichothecenes (T2), aflatoxins and fumonisins. Monthly, five birds were selected at random from each group of birds (A, B and C), afterwards the birds were euthanized and collected from liver and kidney blood samples. The blood was centrifuged to obtain the serum for analysis of serum biochemical tests of aspartate aminotransferase, alanine aminotransferase, albumin, creatine kinase, total proteins, uric acid, cholesterol and urea. The kidney and liver fragments were processed by histological techniques for further histopathological analysis. The results of analysis of mycotoxins present in manufactured diets consisted of lower values than the levels recommended for layers and characterizing underdosing throughout the study. The histopathological renal lesions found were membranoproliferative, membranous and proliferative glomerulopathy, hyperemia, nephritis, nephrosis, necrosis and tulare proteinosis. The histopathological liver lesions found consisted of steatosis, vacuolar degeneration, hepatitis, hypertrophy and microgranuloma of Kupffer cells, hepatocyte necrosis and bile duct proliferation. Serum biochemistry analyzes showed normality in uric acid, alanine aminotransferase and aspartate aminotransferase tests. The total protein, creatine kinase and urea tests obtained higher levels and the albumin test obtained lower levels than those recommended for layers. It was observed that there is a progressive and cumulative effect of kidney injuries depending on the age of the birds, directly correlated with the time of exposure and ingestion of mycotoxins. It is suggested that there is a progressive and cumulative effect of kidney and liver damage as a function of the age of the birds, directly correlated with the time of exposure and ingestion of multimycotoxins.