Effect of chromium methionine supplementation on the lactation performance, hepatic respiratory rate and antioxidative capacity of early-lactating dairy cows

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Effect of Chromium Methionine Supplementation on the Lactation Performance, Hepatic Respiratory Rate and Antioxidative Capacity of Early-Lactating Dairy Cows

Backgrounds: Chromium is an important trace element that may regulate dairy cow metabolism. The objective of this study was to investigate the effect of chromium methionine (Cr-Met) supplementation on lactation performance, hepatic respiratory rate and anti-oxidative capacity in early-lactating Holstein dairy cows. Results: Sixty-four multiparous cows were grouped into 16 blocks based on parity, days in milk and milk production, and four cows within a block then were assigned randomly to one of four dietary treatments with 0, 4, 8 or 16 g/d of Cr-Met per cow in addition to a basal diet. The experiment lasted for 14 weeks, with the first two weeks as adaptation period. Milk yield and composition were recorded weekly. Dry matter intake was measured every other week. The plasma variables were measured in weeks 4, 8 and 12 of the experiment. Supplementation of Cr-Met did not affect dry matter intake of early-lactating dairy cows. As the supplementation of Cr-Met increased, yields of milk, fat, lactose and energy corrected milk increased in a linear manner (P < 0.01). In terms of plasma variables, insulin concentration decreased in a linear manner with Cr-Met supplementation (P = 0.04). As for variables relative to hepatic respiration rate, concentrations of pyruvate and NADH in the plasma were increased in linear (P < 0.01) and quadratic manners (P < 0.01), and lactic dehydrogenase activity was linearly increased as the feeding levels of Cr-Met increased (P < 0.01). Moreover, plasma glutathione peroxidase and superoxide dismutase activity were increased in a linear manner (P < 0.01). Conclusion: The results suggest that Cr-Met supplementation improved lactation performance of early-lactating dairy cows through enhancing antioxidant capacity and hepatic cellular respiration.

Impacts of feeding zinc-methionine or chromium-methionine on performance, antioxidant status and physiological responses to transportation stress on lambs

Context Road transportation of farm animals is an unavoidable activity in animal husbandry, which may lead to the stress. Metabolic modifiers, such as minerals, may be an effective strategy to improve the performance and immune system of animals. Aims The present study examined the effects of chromium-methionine (Cr-Met) and zinc-methionine (Zn-Met) supplementation on animal performance and response to transportation stress. Methods Eighteen lambs (18–20 weeks of age) were randomly assigned to the following three dietary treatments for 10 weeks: (1) basal diet (control, 0.021 g/kg Zn and 0.0001 g/kg Cr); (2) basal diet with addition of 10 Cr-Met mg/kg DM (containing 1 mg/kg Cr); and (3) basal diet with addition of 500 Zn-Met mg/kg DM (containing 50 mg/kg Zn). After a 6-week supplementation period, the lambs were transported by road for 3 h. Key results Mineral supplements did not affect final bodyweight, average daily gain or feed conversion ratio. The blood cortisol and aspartate aminotransferase concentrations were increased (P &lt; 0.05) immediately after transportation (AT1) in all groups; however, they were lower in supplemented lambs than in the control (P &lt; 0.05). Animals fed Cr-Met or Zn-Met diets had a higher albumin concentration at AT1 than did the control group (P &lt; 0.05). Lambs on the Zn-Met diet showed a higher blood triiodothyronine and triiodothyronine to thyroxin ratio at AT1 and at 24 h after transportation (AT2) than did lambs receiving the control diet (P &lt; 0.05). Lambs fed the Cr-Met diet had a lower blood malondialdehyde at AT1 and AT2 than did the control lambs (P &lt; 0.05). Total antioxidant capacity (TAC) was higher in the Zn-Met-supplemented group than in other groups (P &lt; 0.05). Supplementation with dietary Zn-Met increased serum TAC concentration in the kidney tissue compared with the control (P &lt; 0.05), but had no effect on superoxide dismutase and glutathione peroxidase activities. The Cr-Met group showed also a lower malondialdehyde concentration (P &lt; 0.05) and higher TAC, superoxide dismutase and glutathione peroxidase activities in the liver tissue (P &lt; 0.05). Conclusions Dietary supplementation with 10 mg Cr-Met/kg (1 mg Cr) in comparison to 500 mg Zn-Met/kg (50 mg Zn) improved the stress response of lambs subjected to a short-time road transportation, whereas growth performance was not affected. Implications The administration of Cr-Met or Zn-Met to diet of lambs before transportation could reduce the adverse effects of road transportation stress.