Impacts of propolis and Spirulina platensis supplementation on growth, nutrient digestibility, and gut microbiota of Japanese quails under heat stress

This experiment determined the effects of Propolis (PRO) and Spirulina platensis (SP) powder on Japanese quail growth performance, nutrient digestibility, and certain serum parameters under heat stress condition. A total of two hundred unsexed Japanese quails (seven days old) were randomly assigned to four treatments. Each treatment included five replicates (10 quails per each). For five weeks, quail chicks were fed basal diet without supplementation (control), quail chicks were fed basal diet supplemented with 400 mg/kg of PRO, quail chicks were fed basal diet supplemented with 1 g/kg of Spirulina platensis powder (SP), and quail chicks were fed basal diet supplemented with same amount of propolis and Spirulina platensis powder (Mix). Data analysis revealed that supplementation of PRO at 400 mg/kg to quails diet greatly improved (P = 0.001) body weight, body weight gain, feed conversion ratio (FCR) as well as improved ether extract, crude protein digestibility (P = 0.028), serum concentration of albumin, serum total cholesterol in addition to reduced (P < 0.001) the count of Bacillus SPP, Escherichia coli (E. coli), Clostridium Spp, and Enterococcus Spp under heat stress condition. Dietary inclusion of SP at a dose of 1 g/kg alone or in combination with PRO significantly (P = 0.001) improved FCR, serum concentration of albumin in addition to reduced digestibility of ether extract and serum concentration of triglyceride (P = 0.001) compared to the control group. In conclusion, when used individually, propolis (400 mg/kg) and Spirulina (1 g/kg) improved performance and health status of Japanese quails under heat stress; however, their combination did not yield additive benefits.