Rajasthan University of Animal and Veterinary Sciences, Bikaner, Rajasthan, India.
National Bureau of Animal Genetic Resources, Karnal, 132001, Haryana, India.
Int J Biometeorol. 2022 Aug;66(8):1515-1529. doi: 10.1007/s00484-022-02293-3. Epub 2022 Jun 27.
The selection of climate resilient animal is necessary to secure the future of sustainable animal production. The present investigation therefore was an effort to unravel answers to the adaptation at physiological, hematological, and molecular levels in cows of hot arid region that helps them to survive harsh environment, to continue production and reproduction. This investigation was carried out in indicine cows over a period of one year, encompassing four seasons, wherein physiological data of 50 animals, hematological data of 15 animals, and gene expression profile of 5 animals from each of Sahiwal and Kankrej breeds per season was generated. In total, 5600 physiological observations, 1344 hematological observations, and 480 molecular samples were processed. The meteorological data revealed a high diurnal variation of temperature across seasons, with THI exceeding 80 during the months of summer and hot-humid seasons, indicating significant heat stress (HS). The physiological parameters showed an increasing trend with the incremental THI, with significantly (p < 0.05) higher values of rectal temperature (RT), respiration rate (RR), pulse rate (PR), and body surface temperature (BST) at ventral (VT), lateral (LT), dorsal (DT), and frontal (FT), in both breeds recorded during HS. The hematological pictures also revealed significant (p < 0.05) seasonal perturbations in erythrocytic and leucocytic parameters. Moreover, the molecular response was driven by a significant (p < 0.05) upregulation of all the key HSPs, HSP70, HSP90, HSP60, and HSP40, except HSP27 during the hotter months of summer and hot-humid seasons. The expression of HSF1, an important transcriptional regulator of HSP70 was also significantly (p < 0.05) upregulated during summer season in both breeds. All the molecular chaperones revealed a significant upregulation during the summer season, followed by a decreasing trend by hot-humid season. The study indicated a well-developed thermotolerance mechanism in animals of both breeds, with Kankrej cows exhibiting better thermotolerance compared to Sahiwal cows.
为了确保可持续动物生产的未来，选择适应气候变化的动物是必要的。因此，本研究旨在揭示炎热干旱地区奶牛在生理、血液和分子水平上的适应机制，帮助它们在恶劣环境中生存，继续生产和繁殖。本研究在萨希瓦尔牛和卡克瑞牛两种牛种中进行，为期一年，涵盖四个季节，每个季节对 50 头奶牛进行生理数据、15 头奶牛进行血液数据和 5 头奶牛进行基因表达谱数据的采集。总共处理了 5600 个生理观测值、1344 个血液观测值和 480 个分子样本。气象数据显示，整个季节的温度昼夜变化很大，夏季和湿热季节的 THI 超过 80，表明存在显著的热应激（HS）。生理参数随 THI 的增加呈上升趋势，HS 期间，两种牛的直肠温度（RT）、呼吸率（RR）、脉搏率（PR）和腹侧（VT）、外侧（LT）、背侧（DT）和额侧（FT）体表温度（BST）显著升高（p<0.05）。血液图片也显示了红细胞和白细胞参数的显著季节性波动。此外，在夏季和湿热季节，所有关键 HSPs（HSP70、HSP90、HSP60 和 HSP40）除 HSP27 外，均显著上调（p<0.05），驱动了分子反应。HSP70 的重要转录调节剂 HSF1 的表达在夏季两个品种中也显著上调（p<0.05）。所有分子伴侣在夏季均显著上调，随后在湿热季节呈下降趋势。该研究表明，两种牛种的动物都具有发达的耐热机制，卡克瑞牛比萨希瓦尔牛具有更好的耐热性。
