Study On Quick Estimating Of The Nurtrient Contents In Layer Manure

Intensive husbandry caused serious environmental pollution, while disposal of poultry manure to agricultural land is the most economical and environmental sound solution. It was required to estimate the nutrient contents in poultry manure before disposing it to the land. There are two methods for estimating the nutrient contents in poultry manure. The first one is rapid tests based on testing technology; the second one is mathematical model.Studied the rapid tests method, which is based on the testing technology of physical-mechanical characteristics. 26 typical layer manure samples were collected for studying the relationship between physical-mechanical characteristics and the nutrient contents in layer manure. According to the results of analysis, specific gravity and electric conductivity can estimate the P, K contents in layer manure. The influence of dilution to the electric conductivity of the layer manure solutions was tested. With increase of dilution multiple, the electric conductivity declines in power or linearity trend.Studied the mathematical model method, which is based on the data of layers and their dietary intake. In the forced feeding experiment, the relationship between the nutrient contents in layer manure and their dietary intake was analyzed; the impact of diet difference on the nutrient contents in layer manure was also analyzed in this chapter. A series of empirical models were developed by regression analysis. The most reliable, economical and useful models were selected. The nutrient contents in layer feed have direct effect on the nutrient contents in layer manure.Studied the rapid tests method and the mathematical model method simultaneously in the same experiment. The relationship between physical-mechanical characteristics and the nutrient contents in layer manure were developed; the relationship between the nutrient contents in layer manure and their dietary intake was analyzed and developed, too. Then the estimating precisions of the two methods were compared. The most reliable, economical and simple models were selected. The results of the estimation by models were identical with the experiment results on the whole. The precision of the mathematical model method is better than that of the rapid tests method on estimating the N, P and NH/-N content, while estimating the K content the precision of the rapid tests method is better than that of the mathematical model method. The result suggests that the nutrient contents of feed have important effect on the contents in layer manure.At last, the paper put some suggestions about the improvement and the further study on estimation of the nutrient contents in poultry manure in the future.