The effect of cyadox supplementation on metabolic hormones and epidermal growth factor in pigs

Abstract

AbstractThis study was conducted to evaluate the effect of cyadox on endocrine hormones and growth factor in pigs. Forty-eight crossbred pigs (35±7 days) were randomly allotted to one of four treatments, with six replicate pens per treatment and two pigs per pen. Pigs were offered one of four diets including a control diet or the control diet supplemented with cyadox at either 25, 50 or 100 mg/kg for 8 weeks. Growth performance data and serum were collected every 2 weeks. Serum epidermal growth factor (EGF), insulin, thyroid hormones (tri-iodothyronine (T3) and thyroxine (T4)), and cortisol concentrations were determined. Results indicated that average daily gain (ADG) and gain/food ratio increased linearly and quadratically with increasing cyadox levels. The treatment containing cyadox at 50 mg/kg improved ADG by proportionately 0·241 and food efficiency by 0·25 (P<0·05) during the entire experiment. In our study, EGF (during weeks 4 to 8), insulin (during weeks 4 to 6), thyroid hormones (in week 4) concentrations increased quadratrically (P<0·05) and the cortisol concentrations (in week 4) decreased linearly (P<0·01) with increasing supplementation of cyadox. Pigs given 50 mg/kg cyadox diet had greater (P<0·05) EGF concentrations than pigs on other diets throughout the experiment. An increase (proportionately 0·22) in serum insulin concentrations in cyadox group was also observed (P<0·05) in week 4. From week 2 to week 4, the T4concentrations of cyadox group increased by 50% (P<0·05). Moreover, feeding cyadox to pigs elevated their serum T3concentrations (P<0·05) in the 4th week and 8th week. The cortisol concentrations of cyadox group were decreased (P<0·05) in week 4. These results suggest that cyadox improve pig performance by altering concentrations of peripheral metabolic hormones and growth factor.