Department of Animal Science, Iowa State University, Ames, IA 50011, USA.
J Anim Sci. 2024 Jan 3;102. doi: 10.1093/jas/skae250.
Study objectives were to evaluate the effects of mitoquinol (MitoQ) on production parameters, gastrointestinal tract (GIT; stomach and small and large intestines) weight, and circulating leukocytes during a 24-h acute heat stress (HS) challenge. Crossbred gilts [n = 32; 49.1 ± 2.4 kg body weight (BW)] were blocked by BW and randomly assigned to 1 of 4 environmental-therapeutic treatments: 1) thermoneutral (TN) control (n = 8; TNCON), 2) TN and MitoQ (n = 8; TNMitoQ), 3) HS control (n = 8; HSCON), or 4) HS and MitoQ (n = 8; HSMitoQ). Pigs were moved into individual pens and allowed to acclimate for 6 d. The study consisted of 2 experimental periods (P). During P1 (2 d), all pigs remained in TN conditions (20.6 ± 1.5 °C) and were fed ad libitum. During P2 (24 h), pigs were fed ad libitum and exposed to either TN or constant HS (37.3 ± 1.3 °C). Mitoquinol (40 mg/d) was orally administered twice daily (0700 and 1800 hours) during P1 and P2. As expected, pigs exposed to HS had increased rectal temperature, skin temperature, and respiration rate (+1.5 °C, +8.7 °C, and +86 bpm, respectively; P < 0.01) compared to their TN counterparts. Compared to TN, HS pigs had decreased feed intake (67%; P < 0.01) and significant BW loss (+1.5 vs. -1.9 kg, respectively; P < 0.01). Total GIT weight was decreased in HS relative to TN pigs (P < 0.01), and this was influenced by decreased luminal contents (2.43 vs. 3.26 kg, respectively; P < 0.01) and reduced empty GIT mass (3.21 vs. 3.48 kg, respectively; P = 0.03). Stomach contents remained similar between TN and HS pigs (P > 0.54) but tended to increase in MitoQ relative to CON pigs (0.90 vs. 0.63 kg, respectively; P = 0.08). Stomach content as a percentage of the previous 24 h feed intake was increased in HS compared to the TN controls (93% vs. 31%; P < 0.01). In contrast, small and large intestinal contents were decreased in HS compared to TN pigs (23% and 49%, respectively; P < 0.01). Liver weight decreased in HS relative to TN pigs (1.15 vs. 1.22 kg, respectively; P = 0.02), and was decreased in MitoQ compared to CON pigs (1.13 vs. 1.24 kg; P < 0.01). Circulating lymphocytes tended to be decreased in HS relative to TN pigs (16%; P = 0.07). In summary, acute HS increased all body temperature indices, negatively influenced animal performance, and differentially altered GIT motility as evidenced by decreased gastric emptying and increased intestinal transit. However, MitoQ supplementation did not appear to ameliorate these effects.
研究目的是评估 mitoquinol（MitoQ）对生产参数、胃肠道（胃和小肠及大肠）重量和循环白细胞的影响在 24 小时急性热应激（HS）挑战期间。杂交母猪[n=32；49.1±2.4kg 体重（BW）]按 BW 分组并随机分配到 4 个环境治疗处理之一：1） 常温对照（TN）（n=8；TNCON），2）TN 和 MitoQ（n=8；TNMitoQ），3）HS 对照（n=8；HSCON）或 4）HS 和 MitoQ（n=8；HSMitoQ）。猪被转移到单独的围栏中并允许适应 6 天。该研究包括 2 个实验期（P）。在 P1（2 天）期间，所有猪都保持在 TN 条件（20.6±1.5°C）并自由采食。在 P2（24 小时）期间，猪自由采食并暴露于 TN 或恒定 HS（37.3±1.3°C）。Mitoquinol（40mg/d）在 P1 和 P2 期间每天口服两次（0700 和 1800 小时）。正如预期的那样，与 TN 相比，暴露于 HS 的猪的直肠温度、皮肤温度和呼吸率分别升高了 1.5°C、8.7°C 和 86bpm（P<0.01）。与 TN 相比，HS 猪的采食量减少（67%；P<0.01），体重明显减轻（分别为+1.5 和-1.9kg；P<0.01）。与 TN 猪相比，HS 猪的总胃肠道重量减少（P<0.01），这与肠道内容物减少（分别为 2.43 和 3.26kg；P<0.01）和空肠质量减少（分别为 3.21 和 3.48kg；P=0.03）有关。TN 和 HS 猪的胃内容物相似（P>0.54），但与 CON 猪相比，MitoQ 组的胃内容物倾向于增加（分别为 0.90 和 0.63kg；P=0.08）。与 TN 对照组相比，HS 组的胃内容物占前 24 小时采食量的百分比增加（93%比 31%；P<0.01）。相反，与 TN 猪相比，HS 组的小肠和大肠内容物减少（分别为 23%和 49%；P<0.01）。与 TN 猪相比，HS 猪的肝脏重量减少（1.15 比 1.22kg；P=0.02），与 CON 猪相比，MitoQ 组的肝脏重量减少（1.13 比 1.24kg；P<0.01）。与 TN 猪相比，HS 猪的循环淋巴细胞数减少（16%；P=0.07）。总之，急性 HS 增加了所有体温指数，对动物性能产生负面影响，并通过降低胃排空和增加肠道转运来改变胃肠道运动的差异。然而，MitoQ 补充似乎并没有改善这些影响。
