Assessment Of Ammonia And Greenhouse Gases Emissions From Broilers And The Study Of Reduction Effect Using Bacillus

The experiment was conducted to measure broilers ammonia and greenhouse gases emissions byrespiratory chamber, and study the effect of Bacillus （feeding or spraying） on reducing harmful gasesfrom broilers.The experiment was divided into two parts. Experiment1: the measurement of broilers ammoniaand greenhouse gas emissions.300,1-day-old healthy Arbor Acres broilers were selected and randomlyassigned in3respiratory chambers （number of males and females was same）, and the broilers werereared on the net and manure was not cleaned until42d. The results showed that: during42days’growth, the ammonia emissions are2777.78±55.58mg, the average daily ammonia emissions are66.14±1.32mg/bird/d; The total CO₂emissions during42days’ growth are1318.94±480.91g, theaverage daily CO₂emissions are31.40±11.45g/bird/day, The total N₂O emissions are374.01±17.68mg,the average daily N₂O emissions are9.13±0.43mg/bird/day.Experiment2:300,1-day-old healthy Arbor Acres broilers with similar weight were randomlyassigned in3respiratory chambers: Control group, fed with the basal diet; Feeding group, fed with basaldiet containing Bacillus preparation; Spraying group, sprayed Bacillus preparation to the air in thechamber. Each group had four repetitions, and each repetition has25chickens. The gas emissions weremonitored each day during the test for a period of42days. On the21th day and42th day, all the broilerswere weighted and16birds of each treatment were slaughtered. The growth performance, the number offlora and pH in Intestinal and feces, faecal N and serum CO₂content and pH etc were measured. Theresults showed that:（1） There were no significant differences （P>0.05） among different groups inbroilers’ production performance, dry matter and apparent digestibility of energy; crude proteinutilization of broilers fed Bacillus was significantly higher than that of the other two groups’ broilers（P<0.05）;（2） There were no significant differences among different groups in uric acid, urea nitrogencontent in ileum and cecum（P>0.05）; while their contents of feeding and spraying group in feces werehigher than that of control group（P>0.05）.（3） There are no significant differences among differentgroups in serum pH（P>0.05）; broilers’ serum CO₂contents of feeding and spraying group weresignificantly higher than that of the control group on the42th day（P<0.01）;（4） Broilers’ileum pH of thespraying group was significantly lower than that of the control group on the42th day（P<0.05）, andbroilers’ cecal pH of the feeding group is significantly lower than that of the control group on the42thday（P<0.01）.（5） Both feeding and spraying Bacillus can reduce the number of E.coli and salmonellaand increase the number of lactic acid bacteria in cecal chime and feces （P<0.01）, and the number oftotal aerobic bacteria were decreased in feces（P<0.01）.（6） Both feeding and spraying Bacillus canreduce the moisture content （P<0.05） and pH （P<0.01） in manure.（7） During the42-day growth period,the CH₃emissions of feeding and spraying group were23.13%,27.65%higher than the control group.The CO₂emission of the spraying group was44.71%higher than the control group and41.93%higherthan the feeding group. The N₂O emission of the spraying group was43.40%higher than the controlgroup and39.78%higher than the feeding group. The results showed that: Both feeding and sprayingBacillus can reduce ammonia emissions. Feeding Bacillus can not reduce greenhouse gases emissions, while spraying Bacillus can increase greenhouse gases emissions.