Effects of Vitamin A on Beef Quality, Weight Gain, and Serum Concentrations of Thyroid Hormones, Insulin-like Growth Factor-I, and Insulin in Japanese Black Steers

Abstract

The effects of vitamin A on the beef quality, weight gain, and serum concentrations of thyroid hormones, insulin-like growth factor-I (IGF-I), and insulin in Japanese Black steers were investigated.Eight Japanese Black steers which were 14 months old were divided into two groups: high vitamin A group (H) and low vitamin A group (L). The animals in H were injected with 303 mg of vitamin A intramuscularly every month. All steers were given vitamin A added manifestation of clinical VA deficiency. Although there was no difference in feed intake between H and L, the average daily gain (ADG) in H was greater than that in L. The beef marbling in L was significantly better than that in H. The backfat depth in H was significantly thicker than that in L. The serum IGF-I concentrations in L gradually decreased and after the age of 18 months were significantly lower than those at the beginning of the experiment.The serum triiodothyronine concentrations in L were significantly lower than those in H during some periods. The change in the plasma glucose concentrations after the insulin injections (0.2U/kg body weight) was similar in H and L. The glucose infusions (0.2g/kg body weight) caused a marked increase in the plasma insulin concentrations in H and L, and both H and L showed similar areas under curves of plasma insulin levels which were above the basal levels. These results suggested that restricted vitamin A intake led to lower ADG, better beef marbling and lower serum IGF-I and triiodothyronine concentrations.

Effect of feeding rice whole crop silage on growth rate, levels of vitamin A, β‐carotene, vitamin E and IGF‐1 in plasma and skeletal muscle protein degradation in Japanese black calves

“…Vitamin A supplementation in the rations of beef cattle can result in significantly increased growth rates (Oka, Dohgo, et al., ; Wang, Wang, Gong, Wang, & Tan, ). This increase in growth rates is affected by IGF‐1 (Oka, Dohgo, et al., ).…”

“…Vitamin A supplementation in the rations of beef cattle can result in significantly increased growth rates (Oka, Dohgo, et al., ; Wang, Wang, Gong, Wang, & Tan, ). This increase in growth rates is affected by IGF‐1 (Oka, Dohgo, et al., ). In one study, the plasma IGF‐1 and vitamin A concentrations were significantly lower in calves with retarded growth than in clinically healthy calves (Ishibashi et al., ).…”

“…Ishibashi, Ushinohama, Kamimura, and Hamana () reported that the plasma IGF‐1 and vitamin A concentrations were significantly lower in calves with retarded growth than in healthy calves. The plasma IGF‐1 concentration decreases with vitamin A restriction (Oka, Dohgo, Juen, & Saito, ). Administration of β‐carotene increases mass and induces functional hypertrophy in the soleus muscle by promoting IGF‐1‐mediated protein synthesis and reducing ubiquitin‐mediated protein degradation (Kitakaze, Harada Nm Imagita, & Yamaji, ).…”

Genetic parameters of serum vitamin A and total cholesterol concentrations and the genetic relationships with carcass traits in an F1 cross between Japanese Black sires and Holstein dams

“…This concentration is inversely correlated with beef marbling (Pyatt and Berger, 2005). Oka et al (1998a) offered 2 possible explanations for the inverse correlation between marbling score and serum vitamin A concentration. First, retinoic acid, a derivative of vitamin A, may regulate the adipogenic differentiation of fibroblasts and inhibit the terminal differentiation of intramuscular adipose tissue.…”

Surveillance of diarrhea‐causing pathogens in dairy and beef cows in Yamagata Prefecture, Japan from 2002 to 2011

“…infections were identified only in commercial beef cows. Japanese beef cows are usually fed a diet that is low in vitamin A . In particular, no vitamin A is added to their feed during the middle finishing period (16–18 months old) .…”