Determination of ammonia gas concentration in manure of broilers fed with different diets and raised in different raising frequency

This study was conducted to investigate the effects of feeding diets supplemented with mealworm larvae meal fermented with 2 different probiotic bacteria on pH value, moisture and nitrogen content, ammonia gas emission and urease enzyme activity of the manures of broiler chickens reared under 2 different stocking densities. The study was conducted between 16 April 2021 - 22 May 2021. A total of 450 one-day old Ross 308 male broiler chicks were weighed and randomly distributed into 6 groups of similar mean weight each of which included 5 replicates. In a 2 × 3 factorial arrangement, broiler chicks reared under NSD (12 chicks/m2) or HSD (18 chicks/m2) were fed one of 3 different all-mash diets, which were based on corn-soybean meal: CONT – a commercial basal diet which contained no fermented DMLM; FDMLMLP – diet supplemented of fermented DMLM with Lactobacillus plantarum (0.4 %); FDMLMLB – diet supplemented of fermented DMLM with Lactobacillus brevis (0.4 %). Manures were collected between days 21-28, 28-35 and 35-42 in order to determine their pH value, moisture and nitrogen content, the emission of ammonia gas and the activity of the urease enzyme. According to the results of the research; the experimental diets did not significantly affect pH value, moisture and nitrogen content of broiler manures collected between days 21-28, 28-35 and 35-42. However, feeding with FDMLMLP and FDMLMLB diets significantly decreased the emission of ammonia gas and the activity of the urease enzyme of broiler manures collected between days 21-28, 28-35 and 35-42 when compared to the CONT diet. In addition, raising 18 broiler chickens per m2 significantly increased pH value, moisture content, ammonia gas emission and urease enzyme activity of the manures collected between days 21-28, 28-35 and 35-42 when compared to raising 12 broiler chickens per m2. However, the stocking density did not significantly influence the nitrogen content of the manures. While the interaction between the stocking density x experimental diets did not significantly affect pH value, moisture and nitrogen content and ammonia gas concentration of the manures, it significantly affected the urease enzyme activities of the manures. Regardless of stocking density, feeding with FDMLMLP and FDMLMLB diets significantly decreased the activity of urease enzyme belonging to the manures of broiler chickens collected between days 21-28., 28-35. and 35-42. As a result; the pH value, moisture content, ammonia gas concentration and urease enzyme activity of the manures of broilers reared in normal or high stocking density can be reduced by adding mealworm larvae meal fermented with Lactobacillus plantarum or Lactobacillus brevis to the diet.