Abdul-Rahman I I, Robinson J E, Obese F Y, Jeffcoate I A, Awumbila B
Department of Animal Science, Faculty of Agriculture, University for Development Studies, P. O. Box TL 1882, Nyankpala Campus, Tamale, Ghana
Institute of Biodiversity, Animal Health and Comparative Medicine, College of Medical, Veterinary and Life Sciences, University of Glasgow, Bearsden Road, Glasgow G61 1QH, Scotland, UK.
Poult Sci. 2016 Mar;95(3):636-44. doi: 10.3382/ps/pev342. Epub 2015 Nov 2.
The physiological basis of seasonal breeding in the guinea fowl (Numida meleagris) still remains unknown, despite the socioeconomic importance of these birds, particularly in Ghana. A study involving a total of 50 local guinea cocks was conducted, and documented gross anatomical and histological differences in the reproductive organs of breeding and non-breeding male guinea fowls. The study also compared peripheral testosterone concentrations in breeding and non-breeding cocks. Seasonal differences in variables measured were determined using two-tailed t-test/Mann-Whitney U-test. All comparisons were made at 5% level of significance. Breeding males had significantly (P = 0.000) higher anatomical biometric parameters than their non-breeding counterparts. Also, breeding birds had thicker (P = 0.000) phalli than their non-breeding counterparts. Histologically, regressing testis was characterized by the presence of sloughed off cells and increased debris in the tubular lumen and within the excurrent duct system, collapsed tubules and reduction in tubular lumen. Germ and Sertoli cell populations and nuclear diameters and actual seminiferous tubular diameter and length in regressing testes were significantly (P = 0.000) lower than in active testes. Leydig cell nuclear diameters and populations were also significantly (P = 0.000) reduced. Relative volume of seminiferous tubules in the testis, testicular sperm production/mg testis and per testis and peripheral testosterone concentrations were all higher (P < 0.05) in breeding than non-breeding testis. The ducts in the epididymal region also saw significant (P < 0.05) reductions in luminal diameters in non-breeding birds. Significant regression in anatomical and histological structures of the guinea cock reproductive tract occurred during the non-breeding season, and lower peripheral testosterone concentrations may be responsible for this phenomenon.
尽管珍珠鸡（Numida meleagris）具有重要的社会经济价值，尤其是在加纳，但珍珠鸡季节性繁殖的生理基础仍然未知。本研究共纳入了50只当地珍珠鸡公鸡，记录了繁殖期和非繁殖期雄性珍珠鸡生殖器官的大体解剖和组织学差异。该研究还比较了繁殖期和非繁殖期公鸡外周睾酮浓度。使用双尾t检验/曼-惠特尼U检验确定所测变量的季节性差异。所有比较均在5%的显著性水平上进行。繁殖期雄性珍珠鸡的解剖生物测量参数显著高于非繁殖期雄性（P = 0.000）。此外，繁殖期珍珠鸡的阴茎比非繁殖期的更粗（P = 0.000）。在组织学上，退化睾丸的特征是管腔内和输出管道系统内有脱落细胞和碎屑增加、小管塌陷以及管腔缩小。退化睾丸中的生殖细胞和支持细胞数量、核直径、实际生精小管直径和长度均显著低于活跃睾丸（P = 0.000）。间质细胞核直径和数量也显著减少（P = 0.000）。繁殖期睾丸中生精小管的相对体积、每毫克睾丸和每个睾丸的精子产量以及外周睾酮浓度均高于非繁殖期睾丸（P < 0.05）。非繁殖期鸟类附睾区域管道的管腔直径也显著减小（P < 0.05）。在非繁殖季节，珍珠鸡公鸡生殖道的解剖和组织结构出现显著退化，外周睾酮浓度降低可能是导致这一现象的原因。
