Variation among chicken stocks in the fractional rates of muscle protein synthesis and degradation

Abstract

Fractional rates (% X day-1) of synthesis and degradation were determined by measuring the output of N tau-methylhistidine (MeHis) in the excreta at 4 and 8 weeks of age in the chicken. At 4 weeks of age, the fractional rate of synthesis of the meat-type stock was twice that of the egg-type stock (White Leghorn), but the fractional rates of synthesis at 8 weeks of age were similar (4.1-5.1% X day-1) among stocks. The fractional rate of degradation (1.3-1.5% X day-1) of the meat-type stock at 8 weeks of age was less than half the rate of the egg-type stock (2.9% X day-1). The fractional rates of synthesis and degradation at 4 weeks of age in the Satsuma native fowl were relatively high compared with those in the other stocks. In particular, the rate of degradation (8.6% X day-1) at 4 weeks of age was approximately twice that of other stocks. These results show that fractional rates of synthesis and degradation of muscle protein in the chicken differ among genetically diverse groups. The effect of changes in rates of synthesis and degradation on the change in fractional growth rate also differed. From regression coefficients (bks . FGR and bKd . FGR) of these rates in skeletal muscle protein on the fractional growth rate, it was recognized that the change in growth rate accompanies the changes in both synthesis and degradation in White Leghorn and commercial broilers but only the change in synthesis in White Plymouth Rock (dw) and Satsuma native fowl.

Response of Atrogin-1/MAFbx Expression in Various Skeletal Muscles to Fasting in Broiler Chickens

“…Selective breeding of broiler chickens for meat production has led to the generation of strains with accelerated growth rates, in particular which exhibits enhanced growth of the pectoralis (breast) muscle (Griffin and Goddard, 1994, Emmerson, 1997, Konarzewski et al, 2000, Berri et al, 2001. The high rate of accumulation of breast muscle protein in rapidly growing broiler chickens appears to be achieved almost entirely by a marked decrease in the fractional rate of protein degradation (Maeda et al, 1984, Hayashi et al, 1985. In this context, the expression of atrogin-1/MAFbx in different types of muscle fibers (slow-and fast-twitch muscles) and in broiler chickens requires further investigation.…”

“…The accumulation of muscle protein, a key step in muscle growth, is determined by the balance between the rates of protein synthesis and degradation. The high rate of accumulation of breast muscle protein in rapidly growing broiler chickens appears to be achieved almost entirely by a marked decrease in the fractional rate of protein degradation (Maeda et al, 1984, Hayashi et al, 1985. However, the mechanism underlying the reduced protein degradation rate in the pectoralis muscle of broiler chickens has not been determined.…”

Variation among lines selected for body size in the fractional rate of degradation of protein and acid protease activity in the muscle of quail (Coturnix coturnix japonica)

“…Measurement of the fractional rate of degradation of muscle protein was by the method described by Maeda et al (1984Maeda et al ( , 1986. Complete 24-hr excreta collections were individually obtained for 3 days at 2 and 10 weeks of age and stored at -20°C until analyzed for N~-methylhistidine (N'-MH) content.…”

“…The muscle protein turnover rates are affected by not only physiological factors but also genetic factors. The genetic basis for the fractional rates of muscle protein turnover was demonstrated by variations among breeds and lines in the muscle protein turnover rate (Maeda et al, 1984(Maeda et al, , 1986, the effect of a single gene on the muscle protein turnover rate (Maeda et al, 1987a,b), the heterosis effects of the muscle protein turnover rate (Maeda et al, 1988), and genetic parameters of muscle protein turnover rate (Maeda et al, 1989). Recently, Maeda et al (1989) demonstrated that the protein turnover rate in muscle was associated with growth and feed utilization and, additionally, that it may be a characteristic of selection for growth and feed utilization.…”

Changes of Calpain and Calpastatin Activities in Skeletal Muscle with Advancing Age in Growing Period of Broiler and Layer Chickens.

“…The genetic bases of rates of muscle protein turnover have been emphasized by MAEDA et al (1984MAEDA et al ( , 1986MAEDA et al ( , 1991b. The muscle protein degradation rates of layer chickens are higher than those of broiler one, and exhibited downward trends with aging of chickens (HAYASHI et al, 1985;MAEDA et al, 1990).…”