Department of Animal Sciences, Universidade Federal do Vale do São Francisco-UNIVASF, Petrolina, PE, 56300-990, Brazil.
Universidade Federal Rural de Pernambuco-UFRPE, Northeast Biotechnology Network-RENORBIO, Recife, PE, 52171-900, Brazil.
Trop Anim Health Prod. 2022 Sep 22;54(5):314. doi: 10.1007/s11250-022-03320-6.
The aim was to evaluate the effect of residual feed intake (RFI) on the histological, physical and mechanical characteristics of the sheep skin confined in full sun or shade. Dorper sheep (n = 64), male, with an initial bodyweight of 17.8 ± 2.43 kg was confined for 40 days to determine the RFI. After classification, 30 animals with positive RFI and 30 animals with negative RFI were selected, which were distributed in 2 confinement environments. This was a factorial arrangement of 2 (groups of animals-positive RFI and negative RFI) × 2 (environments-full sun and shade), with 15 animals for each combination of factors. The sheep remained in confinement for 60 days. After slaughter, skins were divided in half, and fragments were collected from the right portion for histological sections. The left part of each skin was subjected to tanning. Interaction effect RFI × environment was found in the evaluation of leather fragments in the horizontal direction on elongation at break, leather thickness and tear strength (p < 0.05). An isolated effect of the environment was found on elongation at break of leather fragments in the evaluation on the vertical direction (p = 0.01) and on the number of secondary follicles during the histological evaluation of the dorsal and lateral regions of the skin (p < 0.05). An effect of the interaction RFI × environment was observed for the thermostatic layer of the hip region (p = 0.03). Sheep with positive RFI and kept in confinement in full sun have a leather with greater elongation at break and tear strength, important aspects in determining the quality of the product by the leather industry.
本研究旨在评估剩余采食量（RFI）对完全暴露于阳光或遮阴环境下绵羊皮肤的组织学、物理和机械特性的影响。将 64 只雄性杜泊羊（Dorper sheep）关在一个地方 40 天，以确定其 RFI。在分类后，选择了 30 只具有正 RFI 和 30 只具有负 RFI 的动物，并将它们分配到 2 个封闭环境中。这是一个 2（具有正 RFI 和负 RFI 的动物组）×2（环境-完全暴露于阳光和遮阴）的因子设计，每个因素组合有 15 只动物。绵羊在封闭环境中停留 60 天。屠宰后，将皮肤分成两半，从右侧采集碎片进行组织学切片。每个皮肤的左侧部分进行鞣制。在断裂伸长率、皮革厚度和撕裂强度的水平方向上，RFI×环境的互作效应在皮革碎片的评估中发现（p<0.05）。在垂直方向上，环境对皮革碎片的断裂伸长率（p=0.01）以及皮肤背部和侧面的组织学评估中次级毛囊的数量（p<0.05）有单独的影响。在臀部的恒温层（thermostatic layer），RFI×环境的互作效应观察到（p=0.03）。在完全暴露于阳光的环境中饲养具有正 RFI 的绵羊的皮革具有更大的断裂伸长率和撕裂强度，这是皮革工业确定产品质量的重要方面。
