Abdelnour Sameh A, Al-Gabri Naif A, Hashem Nesrein M, Gonzalez-Bulnes Antonio
Department of Animal Production, Faculty of Agriculture, Zagazig University, Zagazig 44511, Egypt.
Department of Pathology, Faculty of Veterinary Medicine, Thamar University, Dhamar 2153, Yemen.
Animals (Basel). 2021 Feb 2;11(2):373. doi: 10.3390/ani11020373.
Twenty-four adult rabbit bucks ( = 6 per treatment) were fed a basal diet supplemented with 0 (control), 50, 100, and 150 mg proline/kg dry matter (DM) diet for 12 weeks to determine possible usefulness for alleviating the negative impact of environmental heat stress on redox status, haemato-biochaemical attributes and semen quality. There were significant dose-response effects, with increments in levels of dietary proline (LDP) quadratically improving red blood cell counts ( = 0.017), rectal temperature ( = 0.009), and respiratory rate ( < 0.001). Increasing LDP cubically affected superoxide dismutase activity in blood plasma ( = 0.012) and total antioxidant capacity in both blood and seminal plasma ( < 0.001 and = 0.006, respectively). The optimal response was observed at 30 and 80 mg proline/kg DM for blood and seminal plasma, respectively. With regards to homeostasis indexes, increments in LDP cubically modified blood plasma concentrations of total protein ( = 0.002) and albumin ( < 0.001), with an optimal response found at 70 mg proline/kg DM. A linear relationship ( = 0.005) was also observed between LDP and blood plasma glucose concentrations, with the optimal response being found at 100 mg proline/kg DM. Increasing LDP also showed positive effects on reproductive traits, with quadratic increases in blood plasma testosterone and cortisol concentrations ( < 0.001; optimal responses at 50 and 60 mg proline/kg DM, respectively), a positive linear relationship with in libido, ejaculate volume, sperm concentration and total sperm count ( < 0.001 for all; optimal responses observed at 100 mg proline/kg DM) and a quadratic increase in total functional sperm fraction ( < 0.001; optimal response at 70 mg proline mg/kg DM). Hence, the optimal positive effects of dietary proline supplementation on redox status, blood metabolites, and reproductive traits of rabbit bucks may be achieved at 50-100 mg/kg DM.
选用24只成年雄性家兔（每组6只），分别饲喂添加0（对照）、50、100和150毫克脯氨酸/千克干物质（DM）日粮的基础日粮，持续12周，以确定其对减轻环境热应激对氧化还原状态、血液生化指标和精液质量的负面影响的潜在作用。结果显示出显著的剂量反应效应，日粮脯氨酸水平（LDP）的增加使红细胞计数（P = 0.017）、直肠温度（P = 0.009）和呼吸频率（P < 0.001）呈二次方改善。LDP的增加使血浆中超氧化物歧化酶活性（P = 0.012）以及血液和精浆中的总抗氧化能力呈三次方变化（分别为P < 0.001和P = 0.006）。血液和精浆中脯氨酸的最佳添加量分别为30和80毫克/千克DM。就稳态指标而言，LDP的增加使血浆中总蛋白（P = 0.002）和白蛋白（P < 0.001）浓度呈三次方变化，脯氨酸最佳添加量为70毫克/千克DM。LDP与血浆葡萄糖浓度之间也呈现线性关系（P = 0.005），最佳添加量为100毫克/千克DM。LDP的增加对生殖性状也有积极影响，血浆睾酮和皮质醇浓度呈二次方增加（P < 0.001；最佳添加量分别为50和60毫克/千克DM），与性欲、射精量、精子浓度和总精子数呈正线性关系（均为P < 0.001；最佳添加量为100毫克/千克DM），总功能性精子比例呈二次方增加（P < 0.001；最佳添加量为70毫克/千克DM）。因此，日粮中添加脯氨酸对雄性家兔氧化还原状态、血液代谢物和生殖性状的最佳积极影响可能在50 - 100毫克/千克DM时实现。
