Avaliação do estresse oxidativo no parênquima testicular e concentração sérica de testosterona, T3 e T4 em ovinos alimentados com diferentes tipos de palma forrageira

Abstract

The aim of this study was evaluate the influence of differents types of forage palm in testicular oxidative stress, endocrine profile and testicular parenchyma of male sheep Thirty-two male sheep (eight months old) with racial pattern non-defined were used in study. The experimental protocol was approved by ethics committee (n° 053/2015). The animals were fed with diet based on elephant grass hay (GCE) or partial replacement by MIÚDA forage palm (GPM), orelha de elefante mexicana (GOEM) e Ipa Sertânia (GIP) during 63 days. On the day of euthanasia, the testis were removed, fixed in glutaraldehyde 4%, submitted to histological resin processing and stained by toluidine blue. After this, were made testicular histological and morphometric analysis. The animals of IPA sertania group has increased body weight (p<0.001). However, the same group has reduction on epithelium height (GCE p<0.001; GOEM p<0.001; GPM p<0.001), tubular diameter (GCE p<0.001; GOEM p<0.001; GPM p=0.002) and tubular area (p<0.001). All the groups showed degeneration in the germinative epithelium, but the group fed with elephant grass had greater intensity in the lesions than the others. Testosterone levels were higher (p=0.025) in GOEM, GPM and GIP than GCE group. The use of palm Míuda (p=0.002) and IPA sertania (p=0.032) in the diet was efficient on increase of T3 levels compared to GEC. T4 levels were increased in GPM when compared to GEC (p=0.005). According to oxidative stress analysis, catalase levels were increased in GPM in relation to others treatments (GCE p=0.002; GOEM p=0.005; GIP p=0.035). Malondialdehyde levels were higher in GEC (p=0.006) and GPM (p=0.008) than GIP group. Generally, the animals fed with forage palm showed better results in quantitative and qualitative analysis. Thus, the degenerations cannot be attributed on the diets. Nevertheless, the forage palm was effective to create metabolic mechanisms to protection of testicular parenchyma.