Institute of Veterinary Medicine, Federal University of Pará, Av. Dos Universitários, S/n, Castanhal, PA, 68746-360, Brazil.
Laboratory of Biotechnology and Animal Reproduction, Brazilian Agricultural Research Corporation, Embrapa Livestock Southeast Rod, Washington Luiz, Km 234, São Carlos, SP, 13560-970, Brazil.
J Therm Biol. 2022 Jul;107:103258. doi: 10.1016/j.jtherbio.2022.103258. Epub 2022 May 25.
The objective was to evaluate the differences between hair lambs, born from single or twin births, regarding the latency periods for standing up and suckling, the vitality, glycemic, cortisol, and triiodothyronine concentrations, as well as the phenotypic characteristics related to the maintenance of homeothermy in the immediate postpartum. Single (n = 10) or twin (n = 12) Morada Nova lambs were evaluated after birth, during the first successful suckling (M0 = Timepoint 0), and at regular intervals of 20 min (M20, M40, M60). Lambs from single births had higher birth weight (3.09 vs 2.58 kg; P ≤ 0.05) and higher serum triiodothyronine concentration (267 vs 209 ng/dL; P ≤ 0.05) compared to twin lambs. There was a positive correlation between weight and blood glucose (0.57; P ≤ 0.05) for both single and twin lambs. The type of birth did not affect vitality, which was negatively associated with cortisol concentration (-0.53; P ≤ 0.05). Twin lambs had higher internal and ocular temperatures (39.29 vs 38.67 °C and 38.84 vs 38.13 °C; P ≤ 0.05, respectively). Body surface temperatures increased over time in both groups (P ≤ 0.05). An increase in the temperature of the hips region (ysingle = 27.88 + 0.019time; R2 = 0.96; P = 0.019 and ytwin = 28.74 + 0.019time; R2 = 0.94; P = 0.029) was observed for both single and twin lambs, which coincides with the region of brown adipose tissue deposition. The lowest absolute thermal variabilities between twin and single lambs in M0 and M60 were recorded in the midloin and integral dorsal area. The parturition type did not influence the latencies to stand up (P = 0.908) and for the first suckling (P = 0.888), and the vitality score (P = 0.353). Thus, single and twin lambs do not differ in neonatal behavior, but they presented specific metabolic strategies to regulate body temperature over time. Midloin and integral dorsal areas are anatomical regions suggested for use in serial thermographic monitoring. Infrared thermography may be an important complementary resource in neonatal care.
目的在于评估单羔和双羔出生的羔羊在站立和哺乳潜伏期、活力、血糖、皮质醇和三碘甲状腺原氨酸浓度以及与产后即刻维持体温相关的表型特征方面的差异。在第一次成功哺乳（M0=时间点 0）后，以及每隔 20 分钟（M20、M40、M60），对单羔（n=10）或双羔（n=12）Morada Nova 羔羊进行评估。与双羔相比，单羔出生体重更高（3.09 比 2.58 公斤；P≤0.05），血清三碘甲状腺原氨酸浓度更高（267 比 209 纳克/分升；P≤0.05）。单羔和双羔的体重与血糖呈正相关（0.57；P≤0.05）。出生类型不影响活力，活力与皮质醇浓度呈负相关（-0.53；P≤0.05）。双羔的内部和眼部温度更高（39.29 比 38.67°C 和 38.84 比 38.13°C；P≤0.05）。两组的体表温度随着时间的推移而升高（P≤0.05）。双羔和单羔的臀部区域温度都有所升高（ysingle=27.88+0.019时间；R2=0.96；P=0.019 和 ytwin=28.74+0.019时间；R2=0.94；P=0.029），这与棕色脂肪组织沉积的区域相对应。在 M0 和 M60 时，双羔和单羔之间最低的绝对温度变化记录在中腰和整体背部区域。分娩类型对站立潜伏期（P=0.908）和第一次哺乳潜伏期（P=0.888）以及活力评分（P=0.353）均无影响。因此，单羔和双羔在新生儿行为方面没有差异，但它们表现出特定的代谢策略来调节体温。中腰和整体背部区域是建议用于连续热成像监测的解剖区域。红外热成像可能是新生儿护理的重要补充资源。
