Li Mengwei, Hassan Faiz-Ul, Tang Zhenhua, Peng Lijuan, Liang Xin, Li Lili, Peng Kaiping, Xie Fang, Yang Chengjian
Key Laboratory of Buffalo Genetics, Breeding and Reproduction Technology, Ministry of Agriculture and Guangxi Buffalo Research Institute, Chinese Academy of Agricultural Sciences, Nanning, China.
Institute of Animal and Dairy Sciences, University of Agriculture, Faisalabad, Pakistan.
Front Vet Sci. 2020 Sep 4;7:599. doi: 10.3389/fvets.2020.00599. eCollection 2020.
This study was aimed to evaluate the effect of mulberry leaf flavonoids (MLF) on oxidative stress, metabolic hormones, and milk production in Murrah buffaloes. Forty multiparous Murrah buffaloes (4 ± 1 lactations) with similar body weight (average 600 ± 50 Kg) and stage of lactation (90 ± 20 d) were randomly selected for this trial. Four treatment groups (10 buffaloes per group) with different doses of MLF included; control (0 g/d), MLF15 (15 g/d), MLF30 (30 g/d), and MLF45 (45 g/d). Buffaloes were fed with total mix ration consisting of grass (), brewery's grain and concentrate mixture for 5 weeks. Meteorological data including ambient temperature and relative humidity were recorded using the online dust monitoring system to calculate temperature-humidity index (THI). After 1 week of the adaptation, milk yield was recorded daily while physiological parameters (respiratory rate, rectal, and body surface temperature), and milk composition were measured weekly. At the end of the trial, blood samples were collected to analyze serum metabolic hormones including estradiol (E2), growth hormone (GH), prolactin (PRL), Tri-iodothyronine (T3), and Thyroxine (T4). Moreover, serum heat shock proteins (HSP), antioxidants enzymes including malondialdehyde (MDA), total antioxidant capacity (T-AOC), superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GSH-Px) and blood biochemical indices were also analyzed. Results revealed a decrease ( = 0.012) in serum MDA level while increasing ( < 0.01) the HSP and serum GHS-Px contents in supplemented buffaloes. Treatment showed a linear and quadratic decrease ( = 0.001) in the serum T-AOC while reducing CAT contents linearly ( = 0.012) as compared to the control. However, no effect of treatment on serum SOD content was observed. Treatment resulted a linear increase ( = 0.001) in serum GH and PRL hormones while increasing serum E2 levels linearly ( < 0.001) and quadratically ( = 0.025). Treatment increased ( = 0.038) the daily milk yield as compared to the control. However, increase ( < 0.05) in serum T3 and T4 contents, fat corrected milk (4%) and milk protein (%) was observed only in MLF45. Moreover, we observed no change in serum biochemical indices except insulin which linearly increased ( = 0.002) in MLF45. Our findings indicated that MLF at 45 g per day is an appropriate level to enhance milk performance and alleviate heat stress in buffaloes.
本研究旨在评估桑叶黄酮(MLF)对摩拉水牛氧化应激、代谢激素和产奶量的影响。本试验随机选取了40头体重相近(平均600±50千克)且泌乳阶段相似(90±20天)的经产摩拉水牛(4±1胎次)。试验设置了四个不同MLF剂量的处理组(每组10头水牛),分别为对照组(0克/天)、MLF15组(15克/天)、MLF30组(30克/天)和MLF45组(45克/天)。给水牛饲喂由牧草、啤酒糟和精料组成的全混合日粮,持续5周。利用在线粉尘监测系统记录包括环境温度和相对湿度在内的气象数据,以计算温湿度指数(THI)。适应1周后,每天记录产奶量,每周测量生理参数(呼吸频率、直肠温度和体表温度)以及乳成分。试验结束时,采集血样分析血清代谢激素,包括雌二醇(E2)、生长激素(GH)、催乳素(PRL)、三碘甲状腺原氨酸(T3)和甲状腺素(T4)。此外,还分析了血清热休克蛋白(HSP)、抗氧化酶,包括丙二醛(MDA)、总抗氧化能力(T-AOC)、超氧化物歧化酶(SOD)、过氧化氢酶(CAT)和谷胱甘肽过氧化物酶(GSH-Px)以及血液生化指标。结果显示,添加MLF的水牛血清MDA水平降低(P = 0.012),而HSP和血清GSH-Px含量增加(P < 0.01)。与对照组相比,处理组血清T-AOC呈线性和二次曲线下降(P = 0.001),CAT含量呈线性降低(P = 0.012)。然而,未观察到处理对血清SOD含量的影响。处理使血清GH和PRL激素呈线性增加(P = 0.001),血清E2水平呈线性增加(P < 0.001)和二次曲线增加(P = 0.025)。与对照组相比,处理使日产奶量增加(P = 0.038)。然而,仅在MLF45组观察到血清T3和T4含量、乳脂校正乳(4%)和乳蛋白(%)增加(P < 0.05)。此外,除MLF45组胰岛素呈线性增加(P = 0.002)外,未观察到血清生化指标有变化。我们的研究结果表明,每天45克的MLF是提高水牛产奶性能和缓解热应激的适宜水平。