Preliminary Evaluation of Dietary Natustat; Versus Histostat (Nitarsone) for Control of Histomonas meleagridis in Broiler Chickens on Infected Litter

摘要

Histomoniasis (infectious enterohepatitis) is a disease of broiler chickens, turkeys and game fowl which are reared on litter or exposed to range. It is caused by the protozoan organism Histomonas meleagridis . Histomonads are spread in chicken feces, Heterakis gallinarum (cecal worm) eggs or earthworms. Symptoms may include: poor feed conversion ratio and body weight, diarrhea with sulfur-colored droppings, cecal and liver lesions, darkening of the facial regions and sometimes death. Morbidity, mortality and culling may reach 20% in chickens. In the U.S.A., nitarsone (4-nitrophenyl-arsonic acid; Histostat??, Alpharma, Inc., Fort Lee, NJ) is used as an aid in prevention of histomoniasis. In this trial, Natustata"￠ (Alltech, Inc., Nicholasville, KY), a proprietary plant derived product, was used at 1.925 kg/Tonne and compared with nitarsone in the diets of unsexed Hubbard HiY broiler chicks to 42 d of age on histomonad infected litter from broiler breeder s. Infected and uninfected control groups were also included. There were 4 pens each containing 150 chicks (unreplicated live performance) and 25 birds per pen were randomly sampled at 28, 35 and 42 d of age for cecal (0-4) and liver lesion (0-3) scoring. The histomonad infected litter group had significantly elevated cecal and liver lesion scores compared to the uninfected control group, indicating the challenge model was effective. At each sampling point, Natustata"￠ was statistically equivalent to nitarsone for lowering cecal or liver lesion scores and these treatments gave results significantly better than infected control.