Effects of Surgical Caponization on Growth Performance, Fiber Diameter and Some Physical Properties of Muscles in Taiwan Country Chicken Cockerels

Abstract

An experiment was conducted to determine the effects of caponization on the growth performance, breast and thigh muscles physical properties and fiber diameter of the Pectoralis major and Gastrocnemius pars externa in Taiwan country chicken cockerels. Caponized birds were surgically altered at 10 weeks of age. Birds were fed grower and finisher diets ad libitum during an eighteen-week experimental period. The results indicated that the live weight and feed intake in the capons were significantly (p<0.05) higher and the shank length was significantly (p<0.05) longer than in intact birds. There were no significant (p>0.05) differences in feed conversion and mortality between two treatments at 28 weeks of age. Compared with intact birds, the capons had greater (p<0.05) tenderness in the breast and thigh muscles. Cohesion of the breast muscle in the capons was significantly (p<0.05) better than in the intact birds, but the thigh muscles were not significantly (p>0.05) affected. No treatment differences (p>0.05) were associated with cooking loss, muscle chewiness, and elasticity. The capons had a significantly (p<0.05) smaller fiber diameter in the Pectoralis major, but were not significantly (p>0.05) different in the fiber diameter of the Gastrocnemius pars externa. It is concluded that castration did not depress growth compared with the intact birds, but did improve muscle tenderness. This difference was most pronounced in the thigh muscles.

Effects of caponization on growth performance, carcass composition and meat quality of males of a layer line

“…The same result is also reported by Muriel Duran (2004) and Miguel et al (2008) for two native Spanish breeds and recorded live weights until the ages of 32 and 29 weeks, respectively. On the contrary, in other reports, capons were heavier than intact males (Lin and Hsu, 2002;Rahman et al, 2004;Chen et al, 2006). The diversity of these results could be attributed mainly to the variation of the breeds used in these studies.…”

“…With respect to the other quality attributes, it is well documented that caponization has no significant effects on pH 24 and cooking loss (Welter, 1976;Lin and Hsu, 2002;Miguel et al, 2008).…”

Influence of housing system on the growth and histological structure of duck muscles

“…Noteworthy is the fact that the differences in the diameter and cross-sectional area of muscle fibres were greater in biceps femoris muscle mainly in drakes (Figures 2 -5), where they were confirmed significant (MR71 at P <0.01; P44 at P <0.05). According to Lin & Hsu (2002), it may be due to a high concentration of testosterone in blood which stimulates muscle fibres to grow. Gille & Salomon (1998) report additionally that, contrary to gallinaceous poultry, ducks are characterized by more intensive growth of limbs after hatching, and that keeping ducks outdoor predisposes them to increased physical activity.…”

An efficient method of early caponization in slow-growing meat-type chickens

“…However, the tunica albuginea of the testes becomes hard when the birds are caponized at later stages, and this makes removing the testes a more difficult and time-consuming procedure (Rikimaru et al, 2009b). As a result, the BW of capons is lower than that of noncastrated male chickens for some weeks after caponization (Lin and Hsu, 2002;Muriel, 2004;Rikimaru et al, 2009b). Therefore, it is necessary to develop an efficient method for caponization that can be performed in a short time in chickens at an early age.…”