One of the feed additives that have long been used is Antibiotic Growth Promoter (AGP). But nowadays, the use of AGP as a growth promoter has been banned because it has negative impacts such as antimicrobial resistance. Campylobacter jejuni is a pathogenic bacterium that often infects birds, especially broilers. This research aims to investigate the role of synbiotic composed of a prebiotic, and Saccharomyces sp. and Lactobacillus sp. as probiotics (commercial products) in performance of broilers challenged with C. jejuni as a substitute for AGP. Twenty-one Day Old Chicks (DOC) of Cobb-strain broilers were divided into three groups, each consisting of 7 chicks. Group I was given basal diets, group II was given basal diets and AGP (with 250 g/ton of enramycin), and group III was given basal diets and synbiotic (100 gram/100 kg). C. jejuni challenge test was carried out at the 3 rd week. The results suggested that at week 4, group III showed more and significantly different body weight from that of group I, but it did not differ significantly from that of group II. Similarly, at week 4 the weight gain of group III was higher and significantly different compared to that of group I, but did not differ significantly from that of group II. Also, the carcass percentage at week 5 did not differ significantly among the groups, but group III had a higher percentage of carcasses than groups I and II. The addition of synbiotic can replace AGP as a feed additive because it can improve the performance of broilers challenged by C. jejuni.

Feed is the main requirement for broilers farms. However, continuous use of AGP can cause antibiotic resistance in poultry and humans. The effectiveness of feed additives in preventing some disease agents has not been much scrutinized. Among the diseases that often arise is Salmonellosis. This study aims to inspect the role of synbiotics consisting of prebiotics and Saccharomyces sp. and Lactobacillus sp. as the probiotics (commercial product) on the performance and blood values of broilers challenged with Salmonella enteritidis. A total of 36 Cobb-strain DOCs were divided randomly into three groups of 12 with different diets. Group I was given broiler comercial feed, Group II was given comercial feed + AGP (enramycin dosage 250 g/ton), and Group III was given broiler comercial feed + Synbiotics (dosage 100 g/100 kg). Each of the three groups is then further divided into two groups of six, one of which is challenged with Salmonella enteritidis on day 22 (1 x 10 9 CFU/mL) for peroral. Vaccines were then given to all groups: ND + IB on day 7, IBD on day 14, and ND booster on day 18. Blood was collected on day 21 and 35, and body weights were taken every week until week 5. The results of this study showed slight differences in the weight gain amongs the groups, with Group III and group II gaining slightly more weights than Group I. The groups that were challenged with Salmonella enteritidis gained less weight compared to the groups that were not challenged in all groups. No significant difference in blood values was found among the groups. Group II and Group III showed slighty better blood values compared to Grup I. It is concuded, then, that the use of synbiotics (commercial product) as feed additives can replace antibiotic growth promotor (AGP) because the results are almost the same.

The use of probiotics as feed additives in farms has been widely known both at a small and large scale. As a substitute for the Antibiotic Growth Promoter (AGP) that has been banned for animal feed, probiotics are used in broilers feeds to improve their performance. Campylobacter jejuni is a type of pathogenic bacteria that often infect birds, especially broilers, and reduce broiler's performance. This study aims to reveal the role of probiotics in the performance of broilers infected by Campylobacter jejuni. A total of 21 broiler Day Old Chicks (DOC) were divided into 3 groups of 7 with different diets: Group K as the control group were given basal diet, Group BA were given a mixture of basal diet and AGP, and Group BP were given a mixture of basal diet and probiotics. This treatment was implemented for 5 straight weeks. In week 3, a Campylobacter jejuni challenge test was conducted using body weight (BW), body weight gain (BWG), and carcass percentage (CP) as the performance parameters. In terms of BW, from week 1 to week 3 no significant differences were found among the groups. In week 4, however, Group BP had a significantly higher BW that Group K, but insignificantly higher than Group BA. In terms of BWG, from week 1 to week 3 there was also no significant differences among the groups. However, in week 4, BWG in Group BP was found to be significantly higher than that of the other two groups. Finally, in terms of CP, Group BP was found to have higher CP than the other two groups, although the difference is not significant. These results show that probiotics can improve broilers' performance by suppressing Campylobacter jejuni infection.