Study Of Effects Of Acidifer, Probiotics And Their Combinative Adding On Broilers And Their Function Mechanism

In order to meet the needs of people for green food, decreasing the uses of antibiotics in broiler's feeds, we studied the effects of different style acidifer in broilers, at the same time, combined it with probiotics to study their combinative effects, hopining to decrease or replace the uses of antibiotics in broiler's feed. Experiment 1: The experiment were conducted to study the effects of adding 0.15% different kinds of acidifier on the performance of broilers. 200 one-day old commercial broilers were allocated randomly to four treatments of five replicates, ten birds each (male: female, 1:1), the control group using basic diet (no antibiotics). The results shows that adding acidifier can improve the average daily gain,decrease the feed gain ratio and dying ratio of broilers. Effects of former stage are better than that of the latter stage. Among them, the best is treatment 2, the second is treatment 1, and the last is treatment3. Compare with the control group , treatment 2significantly increased the 0~3 week broiler's average daily gain of 5.80%(P<0.05),increased4~5 week broiler's average daily gain of 4.9%(P>0.05),decreased feed gain ratio of 1.6%(P<0.05), dying ratio of 66.67%, increased feed intake of 3.5%,but both insignificant(P>0.05). Experiment 2: The experiment were conducted to study the effects of acidifer, probiotics and their combintion on the broilers performance, intestinal pH and intestinal microflora population of broilers.765 one-day old commercial broilers were allocated randomly to 17 treatments of three replicates,15 birds each,among them ,treatment 1 use basic diets , treatment 17 use antibiotics(aureomysin, 50mg/kg) The addition levels of acidifer are 0.1%,0.2%,0.3%,the addition level of probiotics are 0.2%,0.4%,0.6%. The results show that: Adding different level of acidifer can improve the performance of broilers, the fitting adding level is 0.2%,it significantly increased the broiler's average daily gain of 12.5%(P<0.05), increased feed intake of 3.68% , but insignificant(P<0.05),significantly decreased the feed gain ratio of 13.21%(P<0.05),decreased dying ratio of 33.31%,but insignificant (P>0.05),its effects is worse than the antibiotics treatment(P<0.05). Adding different level of probiotics can improve the performance of broilers, the fitting adding level is 0.4%.Compare with the control group, it significantly increased the broiler's average daily gain of 18.07% ( P<0.05 ) , increased feed intake of 0.98% , but insignificant(P<0.05),significantly decreased the feed gain ratio of 14.47%(P<0.05),decreased dying ratio of 49.96%,but insignificant (P>0.05). Effects of combinative addition of acidifer and probiotics are better than only adding one of them. The best combination is adding 0.1% acidifer and 0.4% probiotics. Compare with the control group, significantly increased the broiler's average daily gain of 28.30%, feed intake of 8.12% ,decreased the feed gain ratio of 15.72%,dying ratio of66.69%(P<0.05), its effects is as good as adding antibiotics. Adding 0.2% acidifer or combinative adding0.1% acidifer and 0.4% probiotics in broiler's daily diet can both significantly decrese the broiler's intestinal pH(P<0.01). Adding 0.2%acidifer or 0.4% probiotics or combinative adding0.1% acidifer and 0.4% probiotics in broiler's daily diet can all decrease the E.Coli concentrion of jejunum and cecum, increasing the Lactobacillus concentrion of jejunum and cecum, but effects of combinative adding 0.1%acidifer and 0.4% probiotics is the best. significantly decreased the E.Coli concentrion of jejunum and cecum(P<0.01),as good as the antibiotics treatment ,significantly increased the Lactobacillus concentrion of jejunum and cecum, its effects is better than then adding antibiotics. Experiment 3: At the 21 day, after weighed the brioers, selected 6 bird (2 each replicates one is male, the other is femal) from the best treatment of only adding acidifer (2,3,4), only adding probiotics (5,9,13) and combinativeadditon of acidifer and probiotics (6,7,8,10,11,12,14,15,16) and zero control group, antibiotics group to study their effects for CPU and MEU. The result shows that adding 0.2% acidifer or adding 0.4% probiotics or combinatively adding o.2% acidifer and 0.4% in broiler feed can all improve the utilization of CP and ME of broiler's daily diets. The effects of Adding 0.4% probiotics is better than that of adding 0.2% acidifer, among them ,the combinative addition is the best , it significantly increased the utilization of CP(P<0.01), decreased the utilization of ME of broiler's daily diets(P<0.05), Its effects is as good as adding antibiotics(P>0.05).