University of Nigeria, Nsukka, Nigeria.
Vet Pathol. 2022 Sep;59(5):773-781. doi: 10.1177/03009858221100432. Epub 2022 Jun 3.
Trypanosomosis of the West African Dwarf (WAD) sheep is often neglected due to emphasis on trypanotolerance. Nevertheless, significant pathological changes may occur in tissues of infected WAD sheep. The purpose of this study was to evaluate the brain, pituitary, and adrenal lesions of (Tbb) and (Tc) infections in WAD rams. Fifteen WAD rams were infected intraperitoneally with Tbb or Tc (10 trypanosomes/animal) or were uninfected controls (5 rams per group). Adrenocorticotrophic hormone (ACTH) and cortisol were assayed in serum by enzyme immunoassay technique. The brain, pituitary, and adrenal glands were processed for histopathology. Serum ACTH levels of infected rams were significantly ( < .05) higher than that of controls on days 14 and 70 post infection (PI). Serum cortisol levels of infected rams were significantly ( < .05) higher than that of controls only on day 14 PI. Mortality was 60% in Tbb- and 40% in Tc-infected rams. The brain of the infected groups showed chromatolysis of cortical neurons and Purkinje cells with severe encephalitis. Degenerative, necrotic, and inflammatory changes were seen in the pituitary and adrenal glands of the infected rams. Adrenal corticomedullary ratio was significantly ( < .05) higher in Tc-infected rams than controls. Based on the high mortality levels, likely due to severe encephalitis, the WAD sheep may not be regarded as trypanotolerant.
西非小尾寒羊（WAD）的锥虫病常因强调对锥虫的耐受性而被忽视。然而，感染 WAD 绵羊的组织可能会发生重大的病理变化。本研究旨在评估 Tbb 和 Tc 感染对 WAD 公羊脑、垂体和肾上腺病变的影响。15 只 WAD 公羊经腹腔接种 Tbb 或 Tc（每只动物 10 个锥虫）或作为未感染对照（每组 5 只公羊）。采用酶联免疫吸附技术检测血清中促肾上腺皮质激素（ACTH）和皮质醇。对脑、垂体和肾上腺进行组织病理学处理。感染公羊的血清 ACTH 水平在感染后第 14 天和第 70 天明显高于对照组（<0.05）。感染公羊的血清皮质醇水平仅在感染后第 14 天明显高于对照组（<0.05）。Tbb 感染组的死亡率为 60%，Tc 感染组的死亡率为 40%。感染组的大脑显示皮质神经元和浦肯野细胞的色氨酸溶解和严重脑炎。感染公羊的垂体和肾上腺可见退行性、坏死和炎症改变。Tc 感染组的肾上腺皮质-髓质比值明显高于对照组（<0.05）。由于可能发生严重脑炎，WAD 绵羊的高死亡率水平表明其可能不被视为耐锥虫。
