Effect of Lactobacilli on production and selected compounds in blood, the liver, and manure of laying hens

Abstract

Summary Lactobacillus species have been reported to reduce nitrogen-containing compounds in poultry manure and produce a safe environment for birds and humans. The effects of Lactobacillus species (Lactobacillus paracasei, Lactobacillus plantarum, and Lactobacillus rhamnosus) on production performance, nitrogenous compounds in manure, specific biological components in serum, and uric acid (UA) concentration in the liver were investigated in an eight-week-long study. Forty-eight white Leghorn hens (52- to 54-week-old) were randomly assigned to 2 treatments; standard drinking water was considered the control, and the treatment included the control and probiotics. Individual probiotics were combined to produce a total concentration of approximately 1.84 × 107 cfu/mL and 6.13 × 106 cfu/mL for each isolate. All layers received the same commercial feed for 8 wk. Nitrogenous compounds measured in manure included ammonia (NH3), ammonium nitrogen (NH4-N), total Kjeldahl nitrogen (TKN), and total nitrogen (TN). Blood serum was analyzed for NH3, UA, total protein, albumin, and creatine kinase. Uric acid concentration was also measured in the liver. No significant effects were observed for body weight, feed intake, egg production, and feed conversion ratio. Ammonia emissions and concentration, NH4-N, TKN, and TN concentration were unaffected; however, the interaction of treatment and week showed significant reduction in NH4-H. Moreover, NH3 concentration was lowered significantly in serum of hens fed with probiotics compared with that of the control. There was no significant effect on UA concentration in the liver. Overall, the results indicated that supplementation of Lactobacillus species could be useful in decreasing NH3 concentration in serum and depositing it in manure where other postconsumption methods (alum and urease inhibitors) could be used to reduce it. Reducing NH3 concentration in serum and in manure should result in more profit for industry in reference to health and productivity of laying hens and welfare of workers. As well, reduction of NH3 concentration satisfies the poultry industry's goal of reducing NH3 emission in the environment.