The experiment was conducted to study the effect of the cooling pad system on the properties and function of litter in pigonlitter system (PLS). The cooling pad system is applied to control the high temperature of pig houses in deeplitter in summer of South China. In this experiment, based on the distance from the cooling pad, the whole house was divided into three areas, the area A approached to cooling pad, the area B located in house center and C approached to fans, in the meantime, in order to monitor the litter change of different depths, litter samples were separately taken from surface layer (0~20cm), the upper layer (20~40 cm), the middle layer (40~60 cm) and the bottom layer (>60 cm). The study consisted of 56 days, sampling once every week.The results showed that no significant differences (P>0.05) were observed in the moisture contents of litter and temperature of pig house among three areas (A, B and C) after applying the cooling pad system in PLS; however, the logarithm of Fungi and activity of urease in litter significantly increased from cooling pad to fans. There were no significant difference (P>0.05) in organic matter, catalase, bacterium, actinomyces and celluloses (P>0.05) among three areas after applying the cooling pad system in PLS, however, the content of organic matter and C/N of litter gradually decreased over the fermentation time. The temperature of litter in surface and bottom layer were significantly lower (P<0.05) than the upper and middle layer, however, the moisture contents of litter in surface layer was significantly lower than (P<0.05) bottom layer, the quantities of microbes and activity of urease of litter gradually reduced from the surface layer to bottom layer, whereas, the activity of catalase of litter did not significantly differ (P>0.05) among four layers; the organic matter of litter in middle and bottom layer was significantly higher than (P<0.05) that of surface layer; the maximum content of ammonium nitrogen in litter appeared in the surface layer, followed by upper layer, middle layer and bottom layer; however, as for nitrate nitrogen of litter, the maximum value appeared in surface layer, followed by upper layer, bottom layer and middle layer. In conclusion,the results suggested that in summer of South China the application of the cooling pad system in PLS had no significant effect on the properties and function of litter, the difference in properties of litter among different depths resulted from the inherent rule of biobed during operational process.
GONG Jun-yong, LIAO Xin-di, YANG Ping, WU Yin-bao.
Effect of Cooling Pad System on Properties and Function ofLitters in PigonLitter System. Journal Of Domestic Animal Ecology. 2012, 33(6): 36-43