Perumal P, De A K, Bhattacharya D, Chakurkar E B
ICAR-Central Island Agricultural Research Institute, Port Blair-744 105, Andaman and Nicobar Islands, Port Blair, India.
Trop Anim Health Prod. 2023 Mar 24;55(2):131. doi: 10.1007/s11250-023-03544-0.
The present study was designed to assess the interrelationship between hematological, serum biochemical, and endocrinological profiles and oxidative stress markers and lactational stages in crossbred (CB) dairy cows of Andaman and Nicobar Islands (ANI). Healthy (n = 6) CB cows (50-62.50% exotic inheritance; Holstein Friesian × Andaman local) of 4 parity with age of 7-9 years and body weight of 350-400 kg were selected from Cattle Breeding Farm, ICAR-Central Island Agricultural Research Institute (ICAR-CIARI), Port Blair, ANI. These experimental cows were synchronized with Ovsynch protocol, and parturition was planned to happen in the month of May-June. Lactation was allowed for 305 days. Hematological profiles, serum biochemical profiles, oxidative stress markers and endocrinological profiles were measured at a 15-day interval from day 07 to 305 of lactation (after 6 days of colostrum). The lactation period was divided into first (day 07 to 90), second (day 91 to 180), and third (day 181 to 305) stage of lactation. Average daily milk yield (L) did not vary among the stages of lactations; however, first (8.56 ± 1.26) and second (9.79 ± 0.87) stages had higher milk yield compared to third (7.93 ± 0.79) stage of lactation. Hematological profiles did not vary among the stages of lactation; however, these values were within the range of bovine species at lactation. Serum glucose, triglyceride, total cholesterol, total protein, globulin, and blood urea nitrogen (BUN) increased (P < 0.05) and albumin and creatinine decreased (P < 0.05) gradually as lactation stages advanced. Activity of aspartate aminotransferase (AST), alanine aminotransferase (ALT), and alkaline phosphatase (ALP) and concentration of calcium, phosphorous, and magnesium were nearly similar among the stages of lactation. Similarly, triiodothyronine (T3), and thyroxine (T4) increased and prolactin and cortisol decreased (P < 0.05) gradually as stages of lactation advanced. Total antioxidant capacity (TAC) increased and malondialdehyde (MDA) decreased (P < 0.05) as lactation stages advanced. The results of the present study indicated that the lactating CB cows suffered nutritional stress (deficiency of protein, carbohydrate, lipids, and minerals), physiological stress (higher cortisol), oxidative stress (higher MDA and deficiency of total antioxidant capacity), and hormonal imbalance (higher prolactin and cortisol and deficiency of thyroid hormones) during the early stages of lactation. Thus, the first and second stages are more stressful events compared to the third stage of lactation in the CB cows in ANI. Therefore, regular monitoring of blood components and accordingly suitable feeding strategies with balanced nutrients and minerals, supplementation of suitable antioxidants, and appropriate management practices need to be implemented to mitigate these stresses and to prevent metabolic disorders with maximum milk production during different stages of lactation in CB cows under humid tropical island ecosystem of Andaman and Nicobar Islands.
本研究旨在评估安达曼和尼科巴群岛（ANI）杂交（CB）奶牛的血液学、血清生化、内分泌特征与氧化应激标志物及泌乳阶段之间的相互关系。从位于ANI布莱尔港的印度农业研究理事会中央岛屿农业研究所（ICAR-CIARI）的种牛养殖场选取了6头健康的CB奶牛（外来遗传比例为50-62.50%；荷斯坦弗里生×安达曼本地牛），胎次为4，年龄7-9岁，体重350-400千克。这些实验奶牛采用Ovsynch方案进行同期发情处理，计划在5-6月分娩。泌乳期为305天。在泌乳第7天至305天（初乳期6天后），每隔15天测量血液学特征、血清生化特征、氧化应激标志物和内分泌特征。泌乳期分为泌乳第一阶段（第7天至90天）、第二阶段（第91天至180天）和第三阶段（第181天至305天）。各泌乳阶段的平均日产奶量（升）无差异；然而，泌乳第一阶段（8.56±1.26）和第二阶段（9.79±0.87）的产奶量高于第三阶段（7.93±0.79）。血液学特征在各泌乳阶段无差异；不过，这些数值在奶牛泌乳期的正常范围内。随着泌乳阶段的推进，血清葡萄糖、甘油三酯、总胆固醇、总蛋白、球蛋白和血尿素氮（BUN）升高（P<0.05），白蛋白和肌酐降低（P<0.05）。泌乳各阶段天冬氨酸转氨酶（AST）、丙氨酸转氨酶（ALT）和碱性磷酸酶（ALP）的活性以及钙、磷和镁的浓度几乎相似。同样，随着泌乳阶段的推进，三碘甲状腺原氨酸（T3）和甲状腺素（T4）升高，催乳素和皮质醇降低（P<0.05）。随着泌乳阶段的推进，总抗氧化能力（TAC）升高，丙二醛（MDA）降低（P<0.05）。本研究结果表明，泌乳期的CB奶牛在泌乳早期遭受营养应激（蛋白质、碳水化合物、脂质和矿物质缺乏）、生理应激（皮质醇水平较高）、氧化应激（MDA较高和总抗氧化能力缺乏）和激素失衡（催乳素和皮质醇水平较高以及甲状腺激素缺乏）。因此，与ANI的CB奶牛泌乳第三阶段相比，第一和第二阶段是压力更大的时期。因此，需要定期监测血液成分，并相应地实施合适的饲养策略，提供营养和矿物质均衡的饲料，补充合适的抗氧化剂，并采取适当的管理措施，以减轻这些应激，预防代谢紊乱，在安达曼和尼科巴群岛潮湿的热带岛屿生态系统下，使CB奶牛在泌乳不同阶段实现最高产奶量。
