Ciclicidade do gás amônia e sua influência em traqueias de frangos de corte

Abstract

The objective was to evaluate the ammonia levels, evaluate histopathological lesions and histomorphometry in broiler chickens. To the experimente, wich was carried out in the city of Garanhuns, PE, 182 chicks of the Ross lineage were used, with 91 birds for each semestre of the year divided into three groups with 28 animals each plus a control group (D0) with 7 animals each. The birds were housed in three unheated broiler houses, measuring 2m x 2m in two cycles, one between the months of february and march, and the second between june and august, of 2019. The bedding used was the most utilized in the region, the rice straw, in shed 1, new bedding was used, in shed 2 litter already fermented from the sheds on the farm itself was used after a production cycle, which was sprayed daily with seven liters of water; and in shed 3, the same bed as in shed 2 was used, but without spraying. The production cycle had a total of 42 days, the birds were euthanized in D0, D7, D21, D35, D42, in wich collections were carried out. The concentration of ammonia gas was checked daily in each shed, in three turns (morning, noon and late afternoon), at the height of the birds and of the employee. Two fragments of trachea (superior portion and inferior portion) were collected, stored in plastic containers with 10% buffered formalina solution and then 70% alcohol until the histological processing. The samples were processed by routine histological techinique, being embedded in paraffin, cut at 3μm, stained in hematoxylin and eosin and analyzed under na optical microscope. It was found that there was no difference between the measurments at diferente heights in the shed, but there is na increase in NH3(ammonia gas) in winter and also in sheds that used reused and reused wet litter. In histomophometry there was no difference between the birds, from diferente sheds in the same cycle, only seasonal, in D35 and D42, the birds raised in the high temperature season had greater tracheal mucosa thickness. In histopathology, the most common lesions were Tracheitis, mucous gland hyperplasia, deciliation and metaplasia of the tracheal epithelium, but there was no statistical difference between groups or between cycles. Keywords: Animal welfare, chronobiology, histomorphometry, poultry, toxic gas.