Skin Breaking Strength in Broilers: Relationship with Skin Thickness

Breaking strength of skin from the breast, back, lateral thigh, and side of 56-day-old male and female broilers was measured in response to diets containing comparatively wide or narrow ratios of calories to protein (C:P). Males had stronger and thinner skin than females, with the differences in thickness being due primarily to differences in the adipose tissue-rich hypodermis. Regardless of sex, feeding diets containing wider C:P ratios resulted in weaker and thicker skin. Increased skin thickness due to these diets was associated with an increase in hypodermis thickness and a decrease in the combined thickness of the dermis and epidermis. Among sites, skin from the breast was strongest, and that from the side was weakest, while skin from the back and thigh exhibited intermediate values for breaking strength. With the exception of differences between the back and thigh, increases in breaking strength occurring between sites were associated with a reduction in total skin thickness and in hypodermis thickness. The results suggest that increased hypodermis thickness or decreased combined thickness of the dermis and epidermis reduces skin strength.