Swain P S, Rajendran D, Rao S B N, Gowda N K S, Krishnamoorthy P, Mondal S, Mor A, Selvaraju S
ICAR-National Institute of Animal Nutrition and Physiology, Bangalore, 560030, India.
Dairy Cattle Nutrition Division, ICAR- National Dairy Research Institute, Karnal, Haryana, 132001, India.
Biol Trace Elem Res. 2023 May;201(5):2416-2426. doi: 10.1007/s12011-022-03355-8. Epub 2022 Jul 25.
The study was conducted to assess nano zinc (ZnN) as a feed supplement with an aim to compare the supplemental dose of inorganic zinc (ZnI). ZnN was synthesized from 0.45 molar (M) zinc nitrate [Zn(NO).6HO] and 0.9 M sodium hydroxide (NaOH) and was confirmed to be of ZnN by TEM-EDAX measurements. Wister albino rats (rats; 84, 53.6 ± 0.65 g) were divided into seven groups (4 replicate with 3 rats each) and given feed supplemented with zinc for 60 days with either of the following diets: (1) normal control (NC): basal diet (BD) + no supplemental Zn; (2) ZnI-25: BD + 25 mg/kg Zn from inorganic ZnO; (3) ZnN-25: BD + 25 mg/kg of ZnN; (4) ZnN-12.5: BD + 12.5 mg/kg of ZnN; (5) ZnN-6.25: BD + 6.25 mg/kg of ZnN; (6) ZnN-3.125: BD + 3.125 mg/kg of ZnN; (7) ZnN-50: BD + 50 mg/kg of ZnN. T and insulin-like growth factor-1 (IGF-1) hormone levels were similar among groups (P > 0.05), whereas T and testosterone were significantly affected, based on supplemented dose. Zn supplementation improved both cell-mediated and humoral immunity. However, both cell-mediated immunity at 24 h and humoral immunity were statistically similar in ZnI-25 and ZnN-6.25 groups. Superoxide dismutase 1 gene expression was found to be similar in all experimental groups. The vascular degeneration were found in liver tissues moderately in NC, mildly in ZnN-6.25 and ZnN-3.125 groups, and no observable changes were noticed in kidney and spleen tissues. However, there was a mild damage in intestinal epithelium of ZnN-25 group rats, hyperplasia of goblet cells, and moderate damage in intestinal villi were observed in ZnN-50 group rats. From the study, it can be concluded that ZnN at half the dose of ZnI showed similar or better responses in terms of immunity, SOD-1 expression, hormonal profiles, and the tissue architecture of vital organs in rats, i.e., 25 mg/kg of Zn from ZnI and 12.5 mg/kg of ZnN impacted similar biological responses like immunity, SOD-1 expression, hormonal profiles, and the tissue architecture of vital organs in rats.
本研究旨在评估纳米锌（ZnN）作为饲料添加剂，并比较其与无机锌（ZnI）的添加剂量。ZnN由0.45摩尔（M）硝酸锌[Zn(NO₃)₂·6H₂O]和0.9 M氢氧化钠（NaOH）合成，并通过透射电子显微镜-能谱仪（TEM-EDAX）测量确认其为ZnN。将Wistar白化大鼠（84只，体重53.6±0.65 g）分为七组（每组4个重复，每个重复3只大鼠），并给予补充锌的饲料60天，饲料添加以下任一种日粮：（1）正常对照组（NC）：基础日粮（BD）+不添加锌；（2）ZnI-25组：BD + 25 mg/kg来自无机氧化锌的锌；（3）ZnN-25组：BD + 25 mg/kg的ZnN；（4）ZnN-12.5组：BD + 12.5 mg/kg的ZnN；（5）ZnN-6.25组：BD + 6.25 mg/kg的ZnN；（6）ZnN-3.125组：BD + 3.125 mg/kg的ZnN；（7）ZnN-50组：BD + 50 mg/kg的ZnN。各组间甲状腺激素（T）和胰岛素样生长因子-1（IGF-1）水平相似（P>0.05），而T和睾酮受添加剂量的显著影响。补充锌可改善细胞介导免疫和体液免疫。然而，ZnI-25组和ZnN-6.25组在24小时时的细胞介导免疫和体液免疫在统计学上相似。所有实验组中超氧化物歧化酶1（Superoxide dismutase 1）基因表达相似。在NC组的肝脏组织中中度发现血管变性，在ZnN-6.25组和ZnN-3.125组中轻度发现，在肾脏和脾脏组织中未观察到明显变化。然而，ZnN-25组大鼠的肠上皮有轻度损伤，ZnN-50组大鼠观察到杯状细胞增生和肠绒毛中度损伤。从该研究可以得出结论，ZnN剂量为ZnI一半时，在免疫、超氧化物歧化酶-1（SOD-1）表达、激素水平和大鼠重要器官的组织结构方面显示出相似或更好的反应，即25 mg/kg来自ZnI的锌和12.5 mg/kg的ZnN对大鼠的免疫、SOD-1表达、激素水平和重要器官的组织结构产生相似的生物学反应。
