Feed formulations to reduce N excretion and ammonia emission from poultry manure.

This summary focuses on reducing nitrogen (N) and ammonia emissions from poultry manure through the use of improved amino acid digestibilities and enzyme supplementation. Proper feed processing techniques, phase feeding, and the minimization of feed and water waste can contribute to additional minor reductions in these emissions. Reductions in environmental pollution can be achieved through improved diet formulation based on available nutrients in the ingredients, reducing crude protein (CP) levels and adding synthetic amino acids. Use of amino acid and CP digestibilities can reduce N excretion up to 40% and a 25% increase in N digestibility can be achieved with enzyme supplementation in broiler diets. Digestibilities can be measured by two methods: the excreta and ileal amino acid digestibilities. Both methods allow amino acid levels to be reduced by 10% or more. Enzyme supplementation decreases intestinal viscosity, improves metabolizable energy levels, and increases amino acid digestibilities. Many feed manufacturers still use total amino acid content to formulate feeds. To meet amino acid requirements, crystalline amino acids are needed. The use of feather, meat and bone meal must not be overestimated or underestimated and the limiting amino acids such as cystine, tryptophan, and threonine must be carefully analyzed.

Effects of chemically amended litter on broiler performances, atmospheric ammonia concentration, and phosphorus solubility in litter.

The effects of 6 different litter amendments on broiler performance, level of atmospheric ammonia (NH3) concentration, and soluble reactive phosphorus (SRP) in litter was determined. Through 3 experiments conducted on 2 different commercial farms, one chemical amendment was added to the litter and then was compared with a control. Broiler performance was not affected by any of the amendments except the ferrous sulfate amendment for which mortality was 25.5%. Application of aluminum chloride (AlCl3 x 6H2O) to the litter lowered atmospheric ammonia concentrations at 42 d by 97.2%, whereas ferrous sulfate (FeSO4 x 7H2O) lowered it by 90.77%. Ammonia concentrations were reduced by 86.18, 78.66, 75.52, and 69.00% by aluminum sulfate [alum or Al2(SO4)3 x 14H2O)], alum + CaCO3, aluminum chloride + CaCO3, and potassium permanganate (KMnO4), respectively, when compared with each control at 42 d. Each amendment except KMnO4 significantly reduced SRP contents. Alum and aluminum chloride were the effective compounds evaluated on the commercial farms with respect to reducing ammonia contents, phosphorus solubility, and mortality.

Effects of storage length and weight loss during incubation on the hatchability of ostrich eggs (Struthio camuelus).

A total of 150 ostrich eggs was collected from two commercial ostrich farms. The eggs were brushed to remove soil and placed into one storage area (15.51 to 15.56 C without controlling humidity) for different periods of time (up to 19 d) before being incubated. After storage, the eggs were kept for 12 h at room temperature, and then washed, disinfected, and dried before being placed into a commercial incubator to determine the effect of length of storage on hatchability. The two supply farms varied by 11.1% in hatchability. The weight of eggs stored for the same lengths of time was not significantly different (P > or = 0.05) between hatched and unhatched eggs. Hatchabilities of ostrich eggs were not affected by days of storage up to 19 d at 15.51 to 15.56 C without controlling the humidity level but, rather, by the amount of weight loss during incubation.

Effect of caecectomy on growth, moisture in excreta, gastrointestinal passage time and uric acid excretion in growing chicks.

1. The effect of caecectomy on nitrogen utilisation and excretion was examined in growing chicks fed on a commercial diet. 2. Caecectomy had no significant effect on food intake or body weight gain. 3. Caecectomy caused significantly higher moisture content in excreta (P<0.01). 4. Gastrointestinal passage time of digesta was significantly shorter in caecectomised chicks than in control chicks (P<0.05). 5. Caecectomy tended to improve nitrogen utilisation rate in growing chicks. 6. The treatment significantly decreased uric acid excretion (P<0.01) and excretory uric acid-N/total nitrogen excretion (P<0.01). 7. It is concluded that the effects of caecectomy on nitrogen metabolism in growing chicks are similar to those in adult chickens.

Effects of cellulase from Trichoderma viride on nutrient utilization by broilers.

Studies were conducted to evaluate the effects of cellulase from Trichoderma viride in a diet for broilers containing high levels of wheat bran. Broiler-type, mixed-sex chicks were fed from 3 to 8 weeks of age. Wheat bran was added at 0, 10, and 20% levels. A fourth group received the 20% wheat bran plus the cellulase enzyme added at the level of .008%. A portion of the chicks was used in a digestibility study with chromic oxide as an indicator. The summarized data showed that cellulose treatment had a significant effect on reducing feed consumption (P less than .01) and an apparent effect in improving feed-to-gain ratio. Cellulase supplementation significantly improved the digestibility of cell wall components (P less than .01). Calcium, phosphorus, iron, zinc, and copper associated with cell walls were solubilized by cellulase. Iron balance was negative in the groups without cellulase; however, iron, which is bound by the bran, apparently was made available for absorption by cellulase.