Variation of Phosphorus in Dry and Wet Deep-Litter Pig Systems

In order to improve the pig litter management and promote the use of phosphorus of litter in farmland,the study investigated the variation of phosphorus in surface,middle and bottom of dry deep litter and wet deep litter with the same long time of use.It is found that water content and the temperature in wet litter were significantly higher than that in dry litter and litter depth had significant effect on the water content,pH and temperature(P0.01),among which the temperature in the middle was the highest.There was no difference between the total phosphorus content in wet litter and in dry litter.Phytate phosphorus in wet litter was significantly lower than that in dry litter,but available phosphorus was inverse(P0.01).Litter depth had significant effect on total phosphorus,phytate phosphorus and available phosphorus(P0.01).The activities of phytase and neutral phosphatase and urease in wet litter were higher than that in dry litter and litter depth had significant effect on the activities of the three enzymes(P0.01).The contents of total phosphorus,phytate phosphorus,available phosphorus and the activities of the three enzymes were the highest in the middle.The interaction of litter sort and litter depth were significant on pH,phytate phosphorus and phytase(P0.01).The result indicates the degradation of phosphorus in litters mainly occurred in the middle and wet litter was more beneficial to the degradation of phytate phosphorus than dry litter and the water content in dry litter should be increased in pig production.