Effect of zinc methionine supplementation on biochemical and hematological indices of growing rabbits

This study was conducted to investigate the influence of different amounts of zinc methionine on the blood biochemistry, hematological parameters and productivity of growing rabbits. Studies have been conducted on 15 rabbits of the Termon white breed, which were randomly divided into three groups of 5 animals in each - one control and two experimental. Animals of the control group were fed with the commercially granulated feed, whereas animals in the experiment group G1 and G2 were fed with the same basal ration supplemented with 10 and 20 mg/kg Zinc-Methionine, respectively. The supplement was added from 50 days of animal age during 40 days. Samples of blood from the marginal ear vein were taken for biochemical and hematologic researches at ten days' intervals during experimental periods. Body weight gain was determined by weighing. High Zn supplementation decreased (P < 0.05) mean corpuscular volume (MCV), mean corpuscular haemoglobin (MCH) and mean corpuscular haemoglobin concentration (MCHC), as compared to control group, while other hematological parameters of rabbits remained unaffected. Results showed that serum albumin concentration were significantly increased on the 70th and on the 80th days of study (P < 0.05) in rabbits received zinc-methionine compared to control animals, while total protein content did not change. The creatinine concentration in the blood of rabbits of the both experimental groups was decreased (P < 0.05) on the 90th day of experiment, as compared to the control. Total cholesterol and triglycerides concentrations were decreased significantly during all period of feeding ZnMet-supplemented diet in both experimental groups. Serum ALT and AST constituent were not significantly affected by dietary treatments comparing to the control. However, serum ALP activity significantly (P < 0.05) increasedon the 80th day of experiment in rabbits fed Zn-Met at the both doses. Also, LDH content was significantly increased (P < 0.05) on the 80th and 90th day of the research in high dose-treated rabbits (G2 group), compared to the low dose-treated animals or control group (P < 0.05). Conclusively, the results revealed that fortification of diet with Zn-Met at level of 10 and 20 mg/kg could significantly enhance the nutrients digestibility of growing rabbits without harmful effect on blood constituents.