Nano zinc supplementation in ruminant's livestock, influence on physiological, immune functions and oxidative stability of West African dwarf goat bucks.

The recent temperature extremes and other associated climatic events pose a detrimental effect to ruminant livestock. To abate this, it is necessary to adopt a functional (biotechnology) approach like the use of nano minerals as feed additives for normal immune function. Nano zinc oxide (nZnO) has demonstrated growth-promoting properties and has been reported to improve antioxidant capacities with high bioavailability recorded in ruminant. This study therefore aimed to research into nano zinc supplementation on growth performance, haematology, serum, oxidative and antioxidant enzymes of West African dwarf (WAD) goats. A total of 18 yearling WAD goats (7.2 ± 0.54 kg) were allocated into 3 treatments of 6 animals per treatment on weight equalization bases. Each group was randomly allotted to three (0, 300 and 600 mg/kg nZnO) experimental diets. Data on haematological parameters, serum minerals and serum biochemical parameters were collected on day 0 and day 84 of the experiment. Data collected were subjected to analysis of variance in a completely randomized design (CRD), and significant means were separated using Tukey's test. It was revealed that West African dwarf goats fed 600 mg/kg nZnO recorded the highest (p < 0.05) PCV and white blood cell values (32.00% and 5.70 × 103/L, respectively) while goats fed 300 mg/kg nZnO recorded the lowest values. At day 84, nZnO supplementation increased serum total protein, globulin and total cholesterol concentration, with higher values (7.57 g/dl, 4.17 g/dl and 95.73 mg/dl) recorded for goats fed 300 mg/kg nZnO. Lower aspartate aminotransferase (66.33 U/L) was observed for goats fed diets containing 300 g/kg nano zinc oxide. Serum minerals (phosphorus, zinc, copper and iron) were elevated in 600 mg/kg nZnO group. Supplementation of nZnO had no significant (p > 0.05) effect on blood superoxide dismutase (SOD) and total bilirubin concentration while reduced (p < 0.05) malondialdehyde (MDA) and urea values were recorded in 300 and 600 mg/kg nZnO supplemented treatments. Goats fed 600 mg/kg nZnO recorded a lower (p < 0.05) glutathione peroxidase value for kidney (24.78 U/mg) and forelimb cut (24.89 U/mg) while kidney, liver and forelimb cut SOD values (4.61, 2.45 and 5.84 U/mg, respectively) were highest at 300 mg/kg nZnO group. The study concluded that supplemented nZnO aided maintenance of and improved the health of the experimental animals through elevated PCV, serum parameters, reduced MDA, urea and other oxidative biomarkers in both serum and organs of West African dwarf goats. [ABSTRACT FROM AUTHOR]