The investigation of the relations between insulin-liked growth factor-I and body weight and between insulin-liked growth factor-I and sex in young cats

Abstract

High plasma IGF-I concentration has been found in large breed young dogs, but not in young cats. The objective of this study was to investigate the relation between the concentration of IGF-I and body weight in both male and female cats at young age. In this study, the plasma IGF-I concentrations and body weight in 4 female and 4 male cats at 5, 11, 17 and 21 months old were examined. No significant difference in the body weight between the female and male kittens (3.1±0.2 kg and 3.2±0.3 kg) at 5 months old was found, but at 11, 17 and 21 months old (5.3±0.2 kg, 5.3±0.4 kg, 5.4±0.2 kg) the male cats had significantly higher body weight (p<0.01) than the female cats (3.1± 0.3 kg, 3.3± 0.2 kg, 3.4±0.3 kg). The IGF-1 concentration in the male cats (945±41 ng/ml) was significantly higher (p<0.05) than that in the female cats (520±39 ng/ml) at the age of 5 months. At 11 and,17 months old, but not at 21 months old, the mean plasma IGF-1 levels (772±122 and 713±33 ng/ml) in the male cats were significantly higher than those in the female cats (323±77 and 197±36 ng/ml) (p<0.05). In conclusion, the results of this study indicated that there were relations between IGF-I and body weight and between IGF-I and sex in young cats. Moreover, the diversity of plasma IGF-1 concentrations in male and female cats can be found at the age of 5 months and over.