Histopatologia e morfometria do fígado de ovinos alimentados com palma forrageira resistente à cochonilha do carmim

Abstract

The aim of this study is to evaluate the liver of sheep fed with forage palm varieties through histological and morphometric evaluations. The experiment was carried out in the Goats and Sheep Sector of the Department of Zootechny of the Federal Rural University of Pernambuco. It was used 40 male sheep with no defined racial pattern, mean body weight of 21.01 ± 2.01 kg and average age of 6 months. The use of the animals was approved by the Committee for Ethics in Animal Experiments (CEUA) (license number: 053/2015). They were distributed in a completely randomized design with 4 treatments and 10 replications, housed in individual stalls equipped with individual feeders and drinking fountains. The experimental treatments were a base diet, composed of elephant grass hay in a partial replacement by small spineless cactus, Orelha of elefante mexicana and IPA-Sertânia. For light microscopy studies, the fragments were processed for inclusion in paraffin, 5 μm thick histological sections were stained in standard staining (HE) and two special stains, PAS and Gomori trichrome. For the hepatic parenchyma morphometry, the relative density (%) was calculated by a total of 4000 points on the histological preparations, per animal. Two palm genotypes had hydrocyanic acid in their composition. Consumption of DM, OM, PB, NDF, NDT, liver weight, body weight at slaughter, alkaline phosphatase enzyme, glucose and cholesterol were higher in animals fed on forage palm. All treatments showed coagulation necrosis and portal triad congestion, and OEM and IPA were different for bile duct. It can be concluded that the use of forage palm in the feed of sheep up to 70 days of confinement does not cause apparent damages to the liver of the animals, the presence of HCN causes coagulation necrosis of lobular pericenter and congestion of the hepatic portal triad.