Impact of dietary enzyme and fermentation treatments on the performance, digestibility, and biochemical profile of broilers consuming guar meal

This study aimed to evaluate the effects of enzyme treatment and fermentation of guar meal on growth performance, nutrient digestibility, and blood biochemistry in broiler chickens. A total of 900 day-old male Hubbard broiler chicks were divided into nine groups based on three levels of guar meal inclusion (3%, 6% and 9%) treated with enzymes (phytase, protease and β-mannanase) or fermented with Bacillus subtilis. The experiment followed a 3 × 3 factorial design, and growth parameters, nutrient digestibility, and blood biochemical analysis were conducted over a 21–day period. Significant (p < 0.05) improvements in feed intake and weight gain were observed in the enzyme-treated and fermented groups compared to untreated controls, particularly at 3% and 6% guar meal levels. Nutrient digestibility was higher for crude protein (p < 0.05) and calcium (p < 0.05) in enzyme-treated and fermented diets, with 3% and 6% inclusion levels showing better digestibility. Blood biochemical analysis indicated lower LDL (p < 0.05) in the fermented group and significant variations in triglycerides (p < 0.05) and HDL (p < 0.05) levels with different inclusion rates of guar meal. These findings suggest that enzyme treatment and fermentation of guar meal can enhance broiler growth performance, nutrient utilisation, and certain blood parameters, with the optimal effect seen at 3% and 6% inclusion levels.