Influence of continuous dietary halofuginone on broiler skin tensile strength and growth performance

Halofuginone was administered to both sexes of 2 broiler strains, Ross and Hubbard, in 4 dietary treatments, 0, 1.5, 3 and 6mg kg-1. Controls received dietary monensin at 100 mg kg-1. Group feed intake and body mass were recorded weekly. Skin tensile strength was monitored on Days 28, 35, 42 and 49 using a standardised cut of breast skin from carcasses randomly drawn from each treatment, strain and sex combination. Halofuginone inclusion level was inversely correlated (r = -0.36) with skin tensile strength and affected both sexes of the 2 strains (P less than 0.01). Between sexes, the skins of cockerels were consistently stronger than those of hens (P less than 0.01). The effect of age (P less than 0.07) and that of strain (P less than 0.06) tended towards significance at the 5% level. The singular effect of halofuginone on skin tensile strength was masked by the interactions treatment and sex (P less than 0.01); treatment and age (P less than 0.02); treatment and strain (P less than 0.06); age and strain (P less than 0.01). An inclusion level of 6mg kg-1, double the recommended level, could reduce growth and skin tensile strength significantly.