Stansberry McKeeley C, Ogundare Wonders, Beckett Linda M, Garcia Reis Leriana, Tobolski Evy M, Anele Uchenna, Richert Brian T, Schinckel Allan P, Casey Theresa M, Minor Radiah C
Department of Animal Sciences, Purdue University, West Lafayette, IN 47906, USA.
Department of Animal Sciences, North Carolina Agricultural and Technical State University, Greensboro, NC 27411, USA.
J Anim Sci. 2024 Jan 3;102. doi: 10.1093/jas/skae356.
Lactating sows and their litters are particularly vulnerable to heat stress (HS). HS decreases fertility, feed intake, milk production, and litter growth of sows. Approaches are needed to mitigate the negative effects of HS on animal welfare and oxidative damage to tissues. The objective of this study was to measure the efficacy of conductive heat removal using electronic cooling pads (ECP) and feeding Moringa oleifera (4% of the diet, M), a feedstuff high in antioxidants, to sows from late gestation to weaning on their welfare and production performance. A study was conducted using a 2 × 2 factorial design of treatments, with mixed parity Yorkshire × Landrace sows (n = 48). The sows were exposed to moderate HS conditions from gestation day 110 to day 21 of lactation. To achieve moderate HS, the farrowing room temperature was increased incrementally daily from 25 °C to 32 °C between 0800 and 1100 hours and decreased from 32 °C to 26 °C between 1700 and 2000 hours. Sows were limit fed during gestation (1.36 kg 2X/d) and fed ad libitum post farrowing. Treatments included HS + control corn-soybean meal (CS)-based diet (HS + CS), HS + M, ECP + CS, ECP + M (n = 12/treatment). Sow respiration rate (RR) and rectal temperature (RT) were measured four times daily (0600, 1300, 1600, and 1900 hours). The use of ECP decreased lactating sow RR (HS = 66.6 bpm, ECP = 28.3 bpm, P < 0.0001), RT (HS = 39.2 °C, ECP = 38.8 °C, P = 0.003), and lactation body weight (BW) loss (HS = -21.67 kg, ECP = -5.1 kg P = 0.002). ECP by time-of-day interactions (P < 0.01) existed for RR and RT, with ECP having a greater impact from 1300 to 1900 hours, than at 0600 hours. ECP increased the intake of lactation feed (P = 0.02). An ECP by diet interaction (P = 0.0004) indicated that ECP increased the intake of lactation feed for the sows fed the CS diet (6.48 vs. 4.42 kg/d, P = 0.0004), but did not affect the feed intake of sows fed the M diet. The treatment did not affect litter weaning weight (P = 0.14). Moringa increased percent fat in milk (M = 12.28%, CS = 11.06%, P = 0.05). The reduction in sow RR and RT, and increase in feed intake with lower loss of BW indicate that ECP improved sow well-being in the HS environment. Neither ECP nor M affected litter growth, despite M increasing fat content of milk and ECP-CS increasing feed intake.
哺乳母猪及其仔猪特别容易受到热应激（HS）的影响。热应激会降低母猪的繁殖力、采食量、产奶量和仔猪生长速度。需要采取措施减轻热应激对动物福利和组织氧化损伤的负面影响。本研究的目的是测量使用电子冷却垫（ECP）和给妊娠后期至断奶的母猪饲喂辣木（占日粮的4%，M）（一种抗氧化剂含量高的饲料原料）对其福利和生产性能的降温效果。采用2×2析因设计进行试验，选用不同胎次的约克夏×长白杂交母猪（n = 48）。从妊娠第110天至泌乳第21天，母猪处于中度热应激条件下。为实现中度热应激，在上午8点至11点之间，产仔室温度每天从25℃逐步升高至32℃，下午5点至8点之间从32℃降至26℃。妊娠期间母猪实行限量饲喂（1.36千克，每天2次），分娩后自由采食。处理组包括热应激+基于玉米-豆粕（CS）的对照日粮（热应激+CS）、热应激+M、电子冷却垫+CS、电子冷却垫+M（每组12头）。每天测量母猪呼吸频率（RR）和直肠温度（RT）4次（上午6点、下午1点、下午4点和晚上7点）。使用电子冷却垫降低了哺乳母猪的呼吸频率（热应激组=66.6次/分钟，电子冷却垫组=28.3次/分钟，P<0.0001）、直肠温度（热应激组=39.2℃，电子冷却垫组=38.8℃，P = 0.003）和泌乳期体重（BW）损失（热应激组=-21.67千克，电子冷却垫组=-5.1千克，P = 0.002）。呼吸频率和直肠温度存在电子冷却垫与时间的交互作用（P<0.01），电子冷却垫在下午1点至晚上7点的影响大于上午6点。电子冷却垫增加了泌乳期采食量（P = 0.02）。电子冷却垫与日粮的交互作用（P = 0.0004）表明，电子冷却垫增加了饲喂CS日粮母猪的泌乳期采食量（6.48千克/天对4.42千克/天，P = 0.0004），但对饲喂M日粮母猪的采食量没有影响。处理组对仔猪断奶体重没有影响（P = 0.14）。辣木增加了乳汁中的脂肪百分比（M组=12.28%，CS组=11.06%，P = 0.05）。母猪呼吸频率和直肠温度的降低以及采食量的增加和体重损失的减少表明，电子冷却垫改善了热应激环境下母猪的健康状况。尽管辣木增加了乳汁中的脂肪含量，电子冷却垫-对照日粮组增加了采食量，但电子冷却垫和辣木均未影响仔猪生长。
