The objective of the present study was to evaluate whether sorghum silage exposure to air for 8, 16 or 24 hr before re-ensiling reduces silage quality and animal feed efficiency. Sorghum was ensiled in 52 metal drums (13 for each exposure time) with 200-L capacity, and after 112 days, 39 drums were opened and silage was exposed to air for 8, 16 or 24 hr. Thirteen silos were not opened and considered control treatment. Subsequently, silage was re-ensiled, and after 56 days, all silos were opened to determine silage quality variables. In addition, the silage was offered to sheep to determine animal feed efficiency. The experimental design was completely randomized with five replications per treatment, and orthogonal polynomials were used to determine linear or quadratic effects of the exposure time. The non-fibrous carbohydrate (NFC) (minimum of 278 g/kg), in vitro dry-matter digestibility (IVDMD) (minimum of 570 g/kg) and lactic acid (1.51 g/kg for each hour) decreased with longer exposure. The pH (0.011 for each hour), ammonia nitrogen (0.057 g/kg for each hour), acetic acid (maximum of 17.9 g/kg) and aerobic stability (maximum of 62.4 hr) increased with longer exposure. Although silage exposure reduced NFC and IVDMD and increased pH and ammonia nitrogen, animal feed efficiency was not compromised. These results indicate that sorghum silage exposure for up to 24 hr does not compromise its use.

中文翻译：

---

热带气候下再青贮对高粱青贮质量、甲烷排放和绵羊效率的影响

本研究的目的是评估在重新青贮前将高粱青贮暴露在空气中 8、16 或 24 小时是否会降低青贮质量和动物饲料效率。高粱在容量为 200 升的 52 个金属桶（每次暴露时间 13 个）中青贮，112 天后，打开 39 个桶并将青贮饲料暴露在空气中 8、16 或 24 小时。13 个筒仓没有打开并被视为对照处理。随后，青贮饲料重新青贮，56 天后，打开所有筒仓以确定青贮饲料质量变量。此外，将青贮饲料提供给绵羊以确定动物饲料的效率。实验设计完全随机，每个处理重复五次，正交多项式用于确定暴露时间的线性或二次效应。非纤维碳水化合物 (NFC)（最低 278 g/kg）、体外干物质消化率 (IVDMD)（最低 570 g/kg）和乳酸（每小时 1.51 g/kg）随着暴露时间的延长而降低. pH 值（每小时 0.011）、氨氮（每小时 0.057 g/kg）、乙酸（最大 17.9 g/kg）和有氧稳定性（最大 62.4 小时）随着暴露时间的延长而增加。尽管青贮暴露降低了 NFC 和 IVDMD 并增加了 pH 值和氨氮，但动物饲料效率并未受到影响。这些结果表明高粱青贮暴露长达 24 小时不会影响其使用。9 g/kg）和有氧稳定性（最长 62.4 小时）随着暴露时间的延长而增加。尽管青贮暴露降低了 NFC 和 IVDMD 并增加了 pH 值和氨氮，但动物饲料效率并未受到影响。这些结果表明高粱青贮暴露长达 24 小时不会影响其使用。9 g/kg）和有氧稳定性（最长 62.4 小时）随着暴露时间的延长而增加。尽管青贮暴露降低了 NFC 和 IVDMD 并增加了 pH 值和氨氮，但动物饲料效率并未受到影响。这些结果表明高粱青贮暴露长达 24 小时不会影响其使用。