Department of Animal and Poultry Nutrition, Faculty of Animal Sciences, Gorgan University of Agricultural Sciences and Natural Resources, Gorgan, Iran.
Department of Animal and Poultry Nutrition, Faculty of Animal Sciences, Gorgan University of Agricultural Sciences and Natural Resources, Gorgan, Iran.
J Therm Biol. 2023 May;114:103585. doi: 10.1016/j.jtherbio.2023.103585. Epub 2023 May 4.
The aim of the current study was to investigate the effects of dietary curcumin nano-micelles (C-NM) on the growth performance, blood metabolites, antioxidant status, and immune and physiological responses of fattening lambs under heat stress conditions. Thirty-two crossbred male lambs [Île-de-France × (Dalagh × Romanov)] with an average weight of 31.2 ± 1.55 kg and age of 4-5 months were assigned to experimental treatments in a completely randomized design including four treatments and eight replications. The treatments were T0, T20, T40, and T80, representing dietary supplementation of C-NM at 0, 20, 40, and 80 mg per head per day, respectively. The study lasted for 37 days including 7 days of adaptation period. Lambs were weighed on days 0 and 30 of the experiment before morning feeding to determine the average daily gain (ADG) and feed conversion ratio (FCR). Blood samples were collected from the jugular vein on day 30 of the experiment and physiological parameters, including rectal temperature (RT), skin temperature (ST), respiration rate (RR), and pulse rate (PR), were measured once a week on a certain day during the study. Lambs in the T40 group showed higher final live weight (FLW) and ADG, while exhibiting lower FCR (P < 0.01). Regression analysis predicted the optimum levels of dietary inclusion of C-NM to be 44.7, 38.3, and 42.0 mg/day for FLW, ADG, and FCR, respectively. Dietary supplementation of C-NM decreased RT, ST, and RR, while increasing PR (P < 0.01). The levels of immunoglobulins G (IgG) and A (IgA) increased linearly with the dietary inclusion of C-NM (P < 0.01), while levels of immunoglobulin M (IgM) remained unaffected (P > 0.05). Dietary inclusion of C-NM had a quadratic reducing effect on the serum concentration of malondialdehyde (MDA) and a cubic increasing effect on the serum activities of glutathione peroxidase (GPx) (P < 0.05). Superoxide dismutase (SOD) was linearly increased in T80, while total antioxidant capacity (TAC) showed a linear increase in T40 and T80 groups (P < 0.01). Based on the results of this study, we recommend the administration of C-NM in the diet of fattening lambs during hot months in tropical and subtropical areas. However, further studies are needed to assess the long-term effects of C-NM during various physiological and production statuses.
本研究旨在探讨日粮姜黄素纳米胶束（C-NM）对热应激条件下育肥羔羊生长性能、血液代谢物、抗氧化状态、免疫和生理反应的影响。将 32 只平均体重为 31.2±1.55kg、年龄为 4-5 月龄的杂交雄性羔羊[Île-de-France×（Dalagh×Romanov）]按完全随机设计分为 4 个处理组，每个处理组 8 个重复。处理组分别为 T0、T20、T40 和 T80，分别代表每头每天补充 C-NM0、20、40 和 80mg。试验持续 37 天，包括 7 天适应期。在实验开始前的早晨喂养前，在第 0 天和第 30 天对羔羊进行称重，以确定平均日增重（ADG）和饲料转化率（FCR）。在试验期间的某一天，每周一次采集颈静脉血样，测量生理参数，包括直肠温度（RT）、皮肤温度（ST）、呼吸频率（RR）和脉搏率（PR）。T40 组的羔羊表现出更高的末重（FLW）和 ADG，同时表现出更低的 FCR（P<0.01）。回归分析预测日粮中 C-NM 的最佳添加水平分别为 FLW、ADG 和 FCR 的 44.7、38.3 和 42.0mg/天。日粮补充 C-NM 降低了 RT、ST 和 RR，同时增加了 PR（P<0.01）。免疫球蛋白 G（IgG）和 A（IgA）水平呈线性增加，而免疫球蛋白 M（IgM）水平保持不变（P>0.05）。日粮 C-NM 的添加量对血清丙二醛（MDA）浓度呈二次降低效应，对血清谷胱甘肽过氧化物酶（GPx）活性呈三次增加效应（P<0.05）。超氧化物歧化酶（SOD）在 T80 中呈线性增加，而总抗氧化能力（TAC）在 T40 和 T80 组中呈线性增加（P<0.01）。基于本研究结果，我们建议在热带和亚热带地区育肥羔羊的日粮中添加 C-NM。然而，需要进一步的研究来评估 C-NM 在不同生理和生产状态下的长期效果。
