Arrebola Francisco, Abecia José-Alfonso
Agriculture, Livestock and Fisheries Research Institute (IFAPA) Hinojosa del Duque, Carretera el Viso, km 2, 14270 Córdoba, Spain.
Environmental Science Research Institute of Aragon (IUCA), University of Zaragoza, Faculty of Veterinary Sciences, Miguel Servet, 177, Zaragoza, Spain.
Vet World. 2017 May;10(5):521-525. doi: 10.14202/vetworld.2017.521-525. Epub 2017 May 13.
This study quantified the effects of season and photoperiodic treatment on semen and seminal plasma (SP) characteristics in 12 bucks of two Spanish goat breeds (Murciano-Granadina, and Payoya) for the past 1 year.
A total of 6 bucks (three of each breed) were exposed to the natural day length and the other six males (three of each breed) were exposed to alternating conditions of 2 months of long days (16 h light) and 2 months of short days (8 h light). Weekly concentrations of glutamic oxaloacetic transaminase/aspartate aminotransferase (GOT/AST), lactate dehydrogenase (LDH), potassium, testosterone, and protein in SP were measured. Reaction time and scrotal circumference were recorded, and plasma testosterone concentrations were measured before semen collection.
Sperm volume, LDH, and potassium concentration in SP, and reaction time did not differ significantly between breeds, seasons, and photoperiodic treatment. Sperm concentrations were higher (p<0.001) in spring and summer than they were in autumn and winter. Mean percentage of positive hypo-osmotic swelling test sperm was the highest in summer and under the artificial photoperiod (p<0.01). GOT/AST concentrations differed (p<0.01) between breeds and seasons. Breed, season, and photoperiod had significant (p<0.001) effects on protein and testosterone levels in SP. Plasma testosterone concentrations were highest in summer (p<0.001), and differed significantly (p<0.01) between breeds. Scrotal perimeter differed significantly (p<0.001) between breeds and photoperiod.
Recognition of those seasonal and breed-specific differences in the performance of bucks should help to improve the management of individual semen samples for use in artificial insemination programs.
本研究对过去一年中两个西班牙山羊品种（穆尔西亚诺 - 格拉纳迪纳和帕约亚）的12只公羊的季节和光周期处理对精液及精浆（SP）特性的影响进行了量化。
总共6只公羊（每个品种3只）暴露于自然日长，另外6只公羊（每个品种3只）暴露于交替的光照条件下，即2个月长日照（16小时光照）和2个月短日照（8小时光照）。每周测量精浆中谷氨酸草酰乙酸转氨酶/天冬氨酸转氨酶（GOT/AST）、乳酸脱氢酶（LDH）、钾、睾酮和蛋白质的浓度。记录反应时间和阴囊周长，并在采精前测量血浆睾酮浓度。
精液体积、精浆中的LDH和钾浓度以及反应时间在品种、季节和光周期处理之间没有显著差异。春季和夏季的精子浓度高于秋季和冬季（p<0.001）。低渗肿胀试验精子阳性的平均百分比在夏季和人工光周期下最高（p<0.01）。GOT/AST浓度在品种和季节之间存在差异（p<0.01）。品种、季节和光周期对精浆中的蛋白质和睾酮水平有显著影响（p<0.001）。夏季血浆睾酮浓度最高（p<0.001），且品种间差异显著（p<0.01）。阴囊周长在品种和光周期之间差异显著（p<0.001）。
认识到公羊性能的这些季节性和品种特异性差异，应有助于改善用于人工授精计划的个体精液样本的管理。
