Effect of Caponisation on Bone Development in Native Male Chickens

Abstract

The aim of the study was to determine the effect of caponisation on the morphometric traits and mechanical parameters of tibial and femoral bones in Greenleg Partridge cocks. The experiment involved 200 cocks. At the age of 8 weeks, 100 birds were subjected to surgical castration. At week 24, the birds were slaughtered and tibial and femoral bones were collected from 10 non-caponised cocks and 10 capons. The caponisation surgery had no effect on the weight and length of any of the long bones but resulted in reduction (P≤0.05) of the ash content in both bones and Ca in the femur. It also influenced the geometric structure of the bones, i.e. there was an increase (P≤0.05) in the second moment of inertia in the tibial bone and the cross-sectional area and mean relative wall thickness in the femoral bone of the capons. The three-point bending test revealed a negative effect of caponisation on the mechanical strength of the bone. Values characterising the highest bone material strength, i.e. yielding load (femur), maximum force moment (tibia) and yielding deformation, bending point resistance, and load-to-deformation (both bones), declined in the capons. The investigations demonstrated a negative effect of caponisation on the quality of long bones. The tibial bone seems to be slightly more sensitive to the caponisation effects than the femoral bone. It can be assumed based on the analysis of biomechanical traits that the bones of capons are more susceptible to deformations or fractures due to their modified geometry and mechanical brittleness.

The effect of caponization on bone homeostasis of crossbred roosters. I. Analysis of tibia bone mineralization, densitometric, osteometric, geometric and biomechanical properties

“…This result is in accordance with similar studies [35,44,53]. In the conducted research, it was noted that castration did not in uence the tibia length in all analyzed rearing period groups of animals, which is consistent with other studies [7,20,30,31,54]. Varied results also apply to the bone mass.…”

“…A similar reduction in bone mass of tibia bone among capons, compared to cockerels was shown by Zawacka et al [44], but only among individuals slaughtered at 24 weeks of age, whereas in the case of 12-week-old animals authors found no such effect. However, similarly to the presented study, other studies report that caponization has no signi cant effect on tibia and femur bone mass [14,30,31,52,54,55].…”

“…In contrast, our study also showed that 24-week-old capons achieved signi cantly higher body weight compared to cockerels. Similar results were observed in a different study [30,31,37]. The differences in body weight of capons, shown in many studies, are likely due to the use of various breeds, lines or crossbred, as well as differences in the duration of rearing, different feeding and the age of the birds at which the castration procedure was performed [39].…”

“…al. [31]. Our study showed no signi cant effect of castration on these parameters, except for the horizontal internal diameter of the 16-week-old individuals' tibia bone, where signi cantly higher values were observed among capons compared to cockerels.…”

“…In the available literature, there is little data on the effect of castration of cockerels on the processes of skeletal development, its growth and mineralization in connection with the development of tibia bone strength properties, and few papers deal with native breeds [30,31]. However, there is a lack of such information with regard to crossbreed hybrids.…”