Effect of dietary supplemental compound probiotics on growth performance, intestinal barrier and immune function of broilers challenged with Clostridium perfringens.

The study was conducted to investigate the effect of dietary supplemental compound probiotics on growth performance, intestinal barrier and immune function of Clostridium perfringens infected broilers. A total of 240 one-day-old Cobb broilers were randomly divided into four groups, which were control group, infected group, compound probiotics 1 + infected group and compound probiotics 2 + infected group, with five replicates in each group, 12 broilers in each replicate. Compound probiotics 1 mainly consisted of Lactobacillus zeae and Lactobacillus plantarum, and compound probiotics 2 mainly contained Lactobacillus paracasei. All infected broilers were inoculated orally with Clostridium perfringenss type A during 14~20 d, and broilers in uninfected group were inoculated with an equal volume of liquid medium. The experiment lasted for 42 d. The results showed that compared with control group, the average body weight and average daily gain of broilers at 21 d and 1~21 d in infected group were significantly decreased (P<0.05), and the average daily gain and average daily feed intake of broilers at 1~42 d in infected group were significantly decreased (P<0.05). Compared with control group, ileum villi height was significantly decreased (P<0.05), spleen index was significantly increased (P<0.05). Compared with infection group, the ratio of jejunum villus height to crypt depth of broilers in compound probiotic 1 + infected group on 21 d and 28 d was significantly increased (P<0.05), and the spleen index was significantly decreased (P<0.05). The average daily gain of broilers from 1 to 42 d in the compound probiotics 2 + infected group was significantly increased (P<0.05), the ratio of jejunum villus height to crypt depth at 28 d was significantly increased (P<0.05), jejunum ZO-1 mRNA level at 21 d was significantly up-regulated (P<0.05), IL-8 mRNA levels in jejunum of broilers at 21 d was significantly down-regulated (P<0.05). The experiment indicates the addition of Lactobacillus paracasei-based compound probiotics to diet can mitigate the negative impact on production performance of Clostridium perfringens-infected broilers. The addition of Lactobacillus-based compound probiotics can improve the intestinal health of broilers. [ABSTRACT FROM AUTHOR]