Influence of dietary enzyme supplementation of barley-based diets on growth performance and footpad dermatitis in broiler chickens exposed to early high-moisture litter

Abstract

SUMMARY The physicochemical properties of dietary nonstarch polysaccharides in barley and soybean meals have been correlated with increases in excreta viscosity and adherence, and hence footpad dermatitis (FPD), in broiler chickens. Moreover, high litter moisture has been identified as a possible causative agent of FPD. A total of 448 birds were raised in floor pens in a design involving a 2 × 2 × 2 factorial arrangement of barley (0 or 25% of diet), feed enzyme mixture (supplementation with 0 or 0.1% of Farmazyme BR-M), and litter moisture (with or without added water) and a 3-stage feeding program (8 treatments; 32 replicates; 4 replicate pens per treatment combination, with 14 birds per pen). In addition to measuring live performance, the feet were scored on all birds at 14, 28, and 42 d of age, and the severity of FPD lesions was recorded as none, mild, or severe. A subsample of birds was processed at the end of the experiment to evaluate carcass yields. Pooled litter samples were collected for moisture determination (d 5 and 42) and pH (d 42). The incidence and severity of FPD on d 14 and 28 were due only to litter moisture. No effects on litter moisture or pH were due to barley, although growth performance was adversely affected at 25% dietary inclusion. Carcass yields did not differ between treatments (P > 0.05). Performance of birds was significantly improved by supplementing the feed enzyme mixture, irrespective of the addition of barley or the wetting treatment. Hence, management factors play a significant role in the etiology of FPD in broilers.