Department of Agriculture, Illinois State University, 301 N. Main Street Ropp Agriculture Building Normal, IL 61790, USA.
Department of Animal Sciences, Purdue University, 270 S. Russell Street Creighton Hall of Animal Sciences, West Lafayette, IN 47907, USA.
Animal. 2019 Nov;13(11):2556-2568. doi: 10.1017/S1751731119001150. Epub 2019 May 28.
Heat stress due to increasing extremes in ambient temperature and humidity results in reduced semen quality in boars. This has caused reduced efficiency of the swine industry, requiring more boars to breed the same number of sows. Vitamins such as vitamin C (VC) and E (VE) have been shown to improve semen quality in boars. Recently, vitamin D has been shown to improve semen quality in boars. The purpose of this experiment was to evaluate the effects of increased supplemental vitamins on boar reproduction during the summer season in a commercial boar stud. One hundred and sixty Pig Improvement Company (PIC) terminal line boars (n = 32 per treatment) and 39 maternal, heat-sensitive boars (n = 7 or 8 per treatment) were randomly allocated to treatment and fed a corn and soybean meal-based diet adjusted based on individual boar body condition score. A control (CNT) diet was used that met PIC recommendations for boars. Increased supplementation of specific vitamins was given in the form of a top-dress and consisted of CNT wheat middlings, CNT plus VC (560 mg/day), CNT plus 25-hydroxy vitamin D3 (VD) (125 µg/day), CNT plus VE (275 mg/day) and CNT plus VC, VD and VE (CDE). The experiment was split into three periods based on maximum daily high temperatures in the barn, where period 1 was weeks 1 to 4, period 2 was weeks 5 to 11 and period 3 was weeks 12 to 14. Semen was collected from boars as needed using the stud's normal production schedule and was analyzed for sperm quantity and quality characteristics. There were no dietary effects on semen volume, sperm concentration or total sperm production (P ≥ 0.553). Total motility of sperm was not impacted by diet (P = 0.115); although, VC tended (P = 0.064) to have a greater progressive motility than CDE. Percentages of morphologically normal sperm and normal acrosomes were not affected by dietary supplementation (P ≥ 0.157). Period effects were observed for most semen quality parameters, with quality generally becoming reduced over time. The present study demonstrates that increased supplementation of vitamins beyond PIC recommendations was not beneficial for boar reproduction during the summer.
由于环境温度和湿度极端升高导致的热应激会降低公猪的精液质量。这导致了养猪业效率降低，需要更多的公猪来繁殖相同数量的母猪。研究表明，维生素 C（VC）和维生素 E（VE）等维生素可以提高公猪的精液质量。最近，维生素 D 已被证明可以提高公猪的精液质量。本实验旨在评估在商业公猪养殖场夏季增加补充维生素对公猪繁殖的影响。160 头 Pig Improvement Company（PIC）终端线公猪（n = 32 头/处理）和 39 头母系、对热敏感的公猪（n = 7 或 8 头/处理）被随机分配到处理组，并根据个体公猪身体状况评分，以玉米和豆粕为基础的日粮进行调整。使用满足 PIC 对公猪推荐的对照（CNT）日粮。以顶部敷料的形式增加特定维生素的补充，包括 CNT 小麦 middlings、CNT 加 VC（560mg/天）、CNT 加 25-羟基维生素 D3（VD）（125µg/天）、CNT 加 VE（275mg/天）和 CNT 加 VC、VD 和 VE（CDE）。实验根据谷仓内最高日高温分为三个时期，第 1 期为第 1 至 4 周，第 2 期为第 5 至 11 周，第 3 期为第 12 至 14 周。根据研究站的正常生产计划，根据需要从公猪身上采集精液，并分析精子数量和质量特征。饮食对精液量、精子浓度或总精子产量没有影响（P≥0.553）。总精子活力不受饮食影响（P=0.115）；然而，VC 似乎（P=0.064）具有更高的前向运动精子比例。形态正常精子和正常顶体的百分比不受饮食补充的影响（P≥0.157）。大多数精液质量参数都存在时期效应，随着时间的推移，质量普遍降低。本研究表明，在夏季，增加 PIC 推荐量以上的维生素补充对公猪繁殖没有益处。
