Impact of different chromium sources on physiological responses, blood biochemicals and endocrine status of heat stress in dairy calves

Dietary Chromium Picolinate Supplementation Improves Glucose Utilization in Transition Calf by Ameliorating Insulin Response

The decrease in insulin sensitivity during the transition of preruminant calves into ruminant animals is the common denominator. Meanwhile, this adaptation predisposes dairy calves towards various health issues and metabolic disorders that occur in later life. Chromium (Cr) has been shown to potentiate insulin functioning and is thereby helpful in reducing the risk of these metabolic disorders. The aim of this study was to assess the effect of Cr supplementation on the insulin sensitivity and health status in Hariana calves during their transition period. A total of 24 preruminant Hariana calves were randomly allocated into four groups (6 calves per group) for a period of 90 days. Calves either received a basal diet devoid of supplemental Cr (control; Cr_0.0 group) or were supplemented with 0.05 mg (Cr_0.05 group), 0.10 mg (Cr_0.10 group), and 0.15 mg (Cr_0.15 group) of Cr per kg BW^0.75 as Cr-picolinate (Cr-Pic). To determine the effect of Cr supplementation on the insulin response, glucose-insulin-non-esterified fatty acids (NEFAs) kinetics was studied during the intravenous glucose tolerance test (IVGTT) and oral glucose tolerance test (OGTT). A rapid glucose disappearance (p < 0.05) with unaltered insulin kinetics during IVGTT and OLTT indicates greater insulin sensitivity in calves supplemented with 0.10 and 0.15 mg of Cr per kg BW^0.75. Improved insulin sensitivity in the Cr_0.10 and Cr_0.15 groups was further confirmed by higher (p < 0.05) values of the insulin sensitivity check index (QUICKI), revised quantitative insulin sensitivity check index (RQUICKI), and lower (p < 0.05) values of the homeostasis model assessment-insulin resistance (HOMA-IR) during IVGTT. Mean serum non-esterified fatty acids (NEFA_m), and insulin receptor substrate-1 (IRS-1) levels were the highest (p < 0.05) and cortisol concentrations were the lowest (p < 0.05) in the Cr_0.15 groups. Unlike IVGTT, there was no effect of treatment, period, and treatment × period interaction on mean serum glucose and insulin levels during OGTT. However, Cr-supplemented calves had a higher (p < 0.05) glucose clearance rate (_gCR). Serum IRS-1 concentrations during OGTT were also higher (p < 0.05) in the Cr_0.10 and Cr_0.15 groups than in the other groups. Serum Cr levels increased dose dependently and were the highest (p < 0.05) in calves fed a diet supplemented with 0.15 mg Cr per kg BW^0.75. There was no effect of treatment on average daily gain (ADG) and body condition score (BCS) while frequency and duration of diarrhea were lower and fecal score was better in Cr-supplemented calves. The current findings show that Cr supplementation improved glucose utilization and health status in calves during their transition period by improving insulin sensitivity.

Effects of dietary chromium supplementation on dry matter intake and milk production and composition in lactating dairy cows: A meta-analysis

Introduction

Chromium (Cr) is an essential mineral that has been demonstrated to enhance milk production in dairy cows. This study aims to evaluate the effects of dietary Cr supplementation on dry matter intake (DMI), milk production and composition using a meta-analysis based on existing literature.

Methods

A random effects meta-analysis was performed to investigate the effects of dietary Cr supplementation on DMI, milk production and composition. The heterogeneity was assessed using the I 2 statistic and Q test, while Egger's test was used to evaluate publication bias.

Results

The meta-analysis discovered that Cr-supplemented cows had a significantly higher DMI compared to those not supplemented, with an increase of 0.72 kg/day [95% confidence interval (CI), 0.46-0.97]. The regression model indicated that DMI significantly increased by 0.9 g/kg of body weight (BW) and by 80.5 g for an increase of 1 mg of Cr supplement. The supplementation phase was associated with an increase in DMI, with an increase of 0.4582 kg/day for BFP (before parturition) and 0.853 kg/day for AFP (after parturition). The methionine and yeast forms of Cr increased DMI by 0.714 and 1.137 kg/day, respectively. The DMI was increased by 2.137 and 0.620 kg/day for multiparous (MP)+ primiparous (PP) cows and MP cows, respectively. Milk production was also increased by Cr supplementation, with an increase of 1.20 kg/day (95% CI, 0.65-1.76). The regression model indicated that milk production increased by 2.3 g/day for an increase of 1 kg of BW and by 122.4 g/day for an increase of 1 mg of Cr supplement. Milk production also increased with the duration of the experiment and days in milk. The amino acid and methionine forms of Cr complexes increased milk production by 1.645 and 1.448 kg/day, respectively. Milk production increased by 1.087 and 1.920 kg/day for MP and PP cows, respectively. Milk composition was not significantly affected by Cr supplementation. Egger's test for publication biases was not significant for all responses of interest.

Discussion

The meta-analysis showed that Cr supplementation improves DMI and milk production in dairy cows. The results suggest that the supplementation phase, form of Cr, and parity should be considered when supplementing dairy cows with Cr. The results have important implications for the dairy industry and can contribute to the development of more effective feeding strategies for dairy cows.

Dietary High Chromium-Methionine Supplementation in Summer-Exposed Finishing Lambs: Impacts on Feed Intake, Growth Performance, and Blood Cells, Antioxidants, and Minerals

This study aimed to investigate the effect of dietary high doses of chromium-methionine (CrMet) supplementation on blood hemato-biochemical parameters and growth performance of finishing lambs reared under warm condition with average temperature-humidity index (THI) of 85.8 unit. Fifteen male lambs (31.9 ± 1.2 kg) fed with either un-supplemented diet (CON) or supplemented with 1.5 (Cr1.5) and 3 (Cr3) mg of Cr/kg dry matter (DM) for 8 weeks. The results showed that high levels of supplemental Cr had no negative impacts on red (RBC) and white blood cells (WBC). Blood total antioxidant capacity (TAOC) tended to be higher in CrMet-fed lambs than those of CON (P < 0.1). Serum malondialdehyde (MDA), as a lipid peroxidation marker, was, respectively, 20.24 and 22.1%, lower in lambs given 1.5 and 3 mg of chromium comparing those of CON (P < 0.05). Moreover, erythrocyte glutathione peroxidase (GSH-PX, U/dL) displayed higher activity in Cr3 (421.2) group than those of CON (334.6) and Cr1.5 (351.2) groups (P < 0.05). Accordingly, GSH-PX activity per gram hemoglobin (U/gHb) was 45.9% greater in lambs of Cr3 than the CON (P < 0.05). Furthermore, feeding 3 mg of Cr led to increased erythrocyte superoxide dismutase (SOD) activity (P < 0.05): as such, SOD was 1193.1, 1281.5, and 1433.0 U/gHb in CON, Cr1.5, and Cr3, respectively. Chromium supplementation linearly decreased serum iron concentration (P < 0.05), but neither blood calcium, phosphorous, copper, zinc, and glucose concentrations nor aspartate aminotransferase and alanine aminotransferase activities were affected by supplemental CrMet. In comparison with CON (1250), lambs in Cr1.5 (1199) and Cr3 (1192) groups had lower daily feed intake (g/d, P < 0.01). In addition, feed to gain ratio was 21.5% lower in the Cr3 group than the control (P < 0.05). Collectively, these findings suggest that feeding summer-exposed finishing lambs with 3 mg of Cr/kg DM improves blood antioxidant status and feed to gain efficiency without adverse effects on lambs' health and metabolism.