RESUMO
This study was aimed to explore the effect of astaxanthin (ASTX) and copper (Cu) supplementation on the growth, immunity, antioxidant, and blood biochemical status of growing Murrah buffalo heifers. Twenty-eight Murrah buffalo heifers were selected and randomly divided into 4 groups (n = 7) after blocking by body weight (BW) (129.86 ± 5.37 kg) and age (9.05 ± 1.02 months). The heifers were fed basal total mixed ration diet without supplementation (CON) or with ASTX (0.20 mg/kg BW; AX), Cu (10 mg/kg DM; CU), or ASTX + Cu (0.20 mg/kg BW + 10 mg/kg DM; AX + CU) for 90 days of study period. The result showed that BW and dry matter intake (DMI) were significantly higher (P < 0.05) in AX + CU than that in other groups. The average daily gain (ADG) and feed conversion efficiency (FCE) were statistically higher (P < 0.05) in treatments than the values observed in CON. The feed conversion ratio (FCR) was reported significantly lower (P < 0.05) in the AX + CU group followed by AX, CU, and CON groups. The total leukocytes count (TLC), lymphocytes, and total immunoglobulin (TIG) were statistically higher (P < 0.05) in AX + CU groups than that found in other groups. However, neutrophil % decreased (P < 0.05) in the AX + CU group than its level in other groups. Superoxide dismutase (SOD), catalase (CAT), and total antioxidant (TAA) levels were observed higher (P < 0.05) in treatments supplemented with ASTX, Cu, or both than CON group. Thiobarbituric acid reactive substance (TBARS) concentration was lower (P < 0.05) in treatments than its level found in the CON group. Glucose level was higher (P < 0.05); however, non-esterifies fatty acid (NEFA) was lower (P < 0.05) in AX + CU than that in others groups. The level of cholesterol (CH), HDL cholesterol (HDL-CH), alkaline phosphatase (ALP), alanine aminotransferase (ALT), and aspartate aminotransferase (AST) were reported lower (P < 0.05) in the AX + CU group followed by CU, AX, and CON groups. The copper (Cu) level was higher (P < 0.05) in CU and AX + CU than AX and CON groups. The result of the present study indicated that the supplementation of ASTX, Cu alone, or their combination improved the growth, immunity, antioxidant status, and liver function of growing heifers.
