Percentages of antimicrobial resistance to Salmonella and Escherichia coli in poultry products were high in Thailand, thus, alternative to antibiotic growth promoter is required. The objective of this experiment aimed to examine the effect of dietary chitosan in broilers on blood and intestinal changes. Total of 392, day-old male Ross 308 broilers were allotted into four groups. Broilers in the control group (group 1) received commercial corn-soybean meal-based basal diet. Chicks in group 2 received basal diet supplemented with 200 ppm amoxicillin. Chitosan was added into the basal diet at 1 and 2 g/kg in groups 3 and 4, respectively. Data on growth performance as well as blood and digesta samples were collected on d 21 and 39. The results showed that 2 g/kg dietary chitosan significantly improved feed conversion ratio (FCR) during d 22-39 and 1-39 (p < .05). This level of chitosan also increased the ratio of villus height (VH) and crypt depth (CD) (p < .05) while decreased the CD (p < .05). The supplementation of 1 and 2 g/kg chitosan in diet tended to reduce the ammonia-nitrogen in colonic digesta. Furthermore, both levels of chitosan enhanced number of Bacillus spp. while decreased number of E. coli (p < .001) leading to increased ratio of Lactobacillus and E. coli (p < .001). There were no significant effects on the heterophil (H): lymphocyte (L) ratio and coefficient of apparent ileal digestibility. In conclusion, the supplementation of 2 g/kg chitosan in broiler diets could be used as an alternative additive to antibiotic with its improvement on gut function. ARTICLE HISTORY

No abstract

The aim of this study was to investigate the application of integrating earthworms (Pheretima peguana) into two-stage pilot-scale subsurface-flow constructed wetlands (SFCWs) receiving swine wastewater in terms of their treatment performance, namely organic content, total kjeldahl nitrogen (TKN), and solid reduction as well as the quantity of sludge production. There was a minor difference in terms of removal efficiency according to each parameter when comparing the unit with earthworms to the one without earthworms. Both achieved the TKN, biochemical oxygen demand (BOD), chemical oxygen demand (COD), total volatile suspended solids (TVSS), suspended solids (SS), and total solids (TS) removal by more than 90 %. The earthworms helped in reducing the sludge production on the surface of constructed wetlands 40 % by volume, which resulted in lowering operational costs required to empty and treat the sludge. The plant biomass production was higher in the wetlands without earthworms. Further research could be undertaken in order to effectively apply earthworms inside the wetlands.

No abstract