不同堆放时间对鸡粪细菌总数的影响

Effect of different stacking time on the total number of bacteria in chicken manure

为了研究陈旧鸡粪转化饲料的生物安全性及其菌落组成,试验采用新鲜鸡粪约1 000 kg,随机分为2组(各500 kg),分别堆放在露天处(E组)和避雨处(C组),每7 d测定细菌总数情况。结果表明:新鲜鸡粪细菌总数为2.72×106cfu/g;菌落形态大多呈圆形,淡黄色,半透明,边缘整齐,表面光滑,提示以大肠杆菌群为主。E组鸡粪细菌总数在堆放第6周达到最小值,为0.24×106cfu/g;在第12周达到最大值,为437.50×106cfu/g。C组鸡粪细菌总数在堆放第9周达到最小值,为0.03×106cfu/g;在第8周达到最大值,为32.14×106cfu/g。E组试验期鸡粪细菌总数平均值为63.14×106cfu/g;比C组的7.66×106cfu/g高约8.24倍。说明新鲜鸡粪堆放过程中的细菌总数受降雨及气温变化等情况的影响。

To study the biological safety of old chicken manure converted to feed and the composition of its colonies, about 1000 kg of fresh chicken manure was used and randomly divided into two groups of about 500 kg each. The two groups were stacked in the open air （ group E） and the shelter from the rain （ group C）, respectively. The total number of bacteria was determined every 7 d. The results showed that the total number of bacteria in the fresh chicken manure was 2.72 ~ 106 cfu/g; and the morphology of the colonies was mostly round, faint yellow and translucent with neat edges and smooth surface, suggesting that the Escherichia coli group dominated the colonies. The total number of bacteria in chicken manure reached a minimum of 0.24×10^6 cfu/g in the Group E stacked at the 6th week, and reached a maximum of 437.50×10^6 cfu/g at the 12th week. The total number of bacteria in chicken manure reached a minimum of 0.03×10^6 cfu/g in the Group C stacked at the 9th week, and reached a maximum of 32.14×10^6 cfu/g at the 8th week. The average of the total number of bacteria in chicken manure of the Group E was 63.14×10^6 efu/g during the trial period, which was about 8.24 times higher than Group C of 7.66×10^6 cfu/g. The results indicate that the changes in rainfall and temperature affect the total number of bacteria in chicken manure during the stacking process.