EFFECT OF A UREASE INHIBITOR AND CEILING FANS ON ASCITES IN BROILERS .1. ENVIRONMENTAL VARIABILITY AND INCIDENCE OF ASCITES

A low ventilation model to induce ascites was introduced and character ized. In addition, the effect of supplemental air mixing via ceiling f ans (CF) and the feeding of a urease inhibitor (0, 125, and 250 ppm) o n incidence of ascites were investigated. Twelve environmental chamber s were utilized in the trial: six were fitted with CF. Each dietary tr eatment was replicated twice per CF treatment. One hundred and twenty day-old male commercial broilers were reared per chamber. Atmospheric O2, CO2, and NH3, temperature, and humidity, as well as weekly litter moisture and pH, were monitored. Chamber CO2 levels increased immediat ely then stabilized. Chamber NH3 levels increased between 2 to 4 wk of age and rapidly declined when ventilation rates were increased to 1 c fm per bird. The CF and dietary treatments had little effect on air or litter variables except for NH3. Supplementing the diet with urease i nhibitor resulted in a greater than 50% reduction in cumulative mortal ity due to ascites and a slight reduction in weekly BW gains. The CF t reatment had no effect on production variables such as weekly feed int ake, gain, and feed to gain ratio, or survivability due to ascites.