The present work aimed to explore the influence and underlying mechanisms involving arginine in testicular development in boars. To this end, thirty 30-day-old male Duroc piglets (7.00 ± 0.30 kg) were randomly sorted into two groups, maintained on either a basal diet (CON, n = 15) or a diet supplemented with 0.8% arginine (ARG, n = 15). Blood and testicular samples were collected during the experimental period to analyse amino acid composition and arginine metabolite levels. The results showed that dietary supplementation with arginine increased number of spermatogonia and height of the seminiferous epithelium (p < 0.05). Sperm density, total number and effective number of sperm of the boars in the ARG group increased significantly compared with those in the CON group (p < 0.05). Although arginine supplementation did not affect plasma amino acid levels, testicular arginine levels in 150-day-old boars exhibited a significant increase (p < 0.05). The level of serum nitric oxide (NO) and activity of nitric oxide synthase (NOS) also increased in 150-day-old boars in the ARG group (p < 0.05). Interestingly, dietary supplementation with arginine increased testicular levels of putrescine in 150-day-old boars (p < 0.05). These results indicated that arginine supplementation increased serum NO levels and testicular arginine and putrescine abundance, thereby improving testicular development and semen quality in boars.

中文翻译：

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精氨酸通过一氧化氮和腐胺促进公猪睾丸发育

目前的工作旨在探索精氨酸对公猪睾丸发育的影响和潜在机制。为此，将 30 天大的雄性杜洛克仔猪 (7.00 ± 0.30 kg) 随机分成两组，维持基础日粮 (CON, n  = 15) 或添加 0.8% 精氨酸 (ARG, n  = 15)。在实验期间收集血液和睾丸样本以分析氨基酸组成和精氨酸代谢物水平。结果表明，日粮中添加精氨酸可增加精原细胞数量和生精上皮高度（p < 0.05)。与CON组相比，ARG组公猪精子密度、精子总数和有效精子数显着增加（p  < 0.05）。虽然补充精氨酸不影响血浆氨基酸水平，但 150 日龄公猪的睾丸精氨酸水平显着增加（p  < 0.05）。ARG 组 150 日龄公猪的血清一氧化氮 (NO) 水平和一氧化氮合酶 (NOS) 活性也增加（p  < 0.05）。有趣的是，日粮中添加精氨酸会增加 150 日龄公猪睾丸中的腐胺水平（p < 0.05)。这些结果表明，精氨酸补充剂增加了血清 NO 水平以及睾丸精氨酸和腐胺的丰度，从而改善了公猪的睾丸发育和精液质量。