Effect of Isolates of Lactobacillus Reuteri and Lactobacillus Salivarius Isolated from the Gastrointestinal Tract of Native Poultry of Northern of Iran on Performance, Serum Lipids and Immune Parameters of Broiler Chickens

The purpose of this study was to investigate the effects of the use of three lactobacillus strains (L. reuteri ABRIG17 (MF686477), L. reuteri ABRIG23 (MF686483), L. reuteri ABRIG3 (MF686463)), Isolated from duodenum and Jejunum sections of the native Guilan chickens and one isolate of L. salivarius NABRII58 (MH595986) isolated from the digestive system of the native ducks of Mazandaran, on serum lipids and immune parameters of broiler chickens. The strains were isolated from 383 gram-positive and catalase negative lactic acid bacteria in a screening procedure for the detection of bacteria with probiotic potential. In the experiment, 500 male Ross 308 male broiler chicks were used in a completely randomized design with 5 treatments, 5 replicates and 20 birds per replicate. The treatments consisted of: 1-The basal diet as control group (treatment C), 2- The basal diet + 1 g / kg of mixed powder containing MF686463 (L. Reuteri ABRIG3 (LR1), 3- The base diet + 1 g /kg of L. Reuteri ABRIG23 (MF686483) (LR2 treatment), 4- The basal diet + 1 g / kg of L. Reuteri (MF686477) ABRIG17 (LR3 treatment) and 5- The basal diet + 1 g / kg of L. Salivarius (MH595986) NABRII58 (Treatment LS). The use of bacterial strains in LR1 and LS treatments resulted in improved weight gain at the end of the experiment (P <0.05). The bacterial strains in LR1 treatment improved daily weight gain in whole experimental period (P <0.05). All three strains of Lactobacillus used, namely, LR1, LR2 and LR3 treatments, caused a significant decrease in abdominal fat pad (P <0.05). In LR3 treatment, the increase in carcass weight was observed (P <0.05). Measuring serum immunoglobulins in broiler chicks after two stages of sheep red blood cell injection showed that LR3 had the highest total immunoglobulin level after the second injection (P <0.05), and IgG levels in the LR1 treatment increased after the first injection compared to the control group (P <0.05). After the second injection, the IgG of all the four experimental groups were higher than control group (P <0.05), but IgM showed no significant difference between experimental treatments and control group. Total serum cholesterol concentration of LR2 treatment was significantly (P <0.05) lower than other treatments. There was no significant difference in serum triglyceride level between control and the LR1, LR2 and LS treatments, and only LR3 triglyceride level was higher than others (P <0.05). The level of HDL or good cholesterol in LS treatment was higher than the control group (P <0.05). Serum LDL level did not show any significant difference between the experimental and control groups. The present study revealed that probiotic bacteria can be isolated from native poultry microbial populations and isolated bacteria can improve the production and immunity of broiler chicks. It is worthy of note that the positive effect of Lactobacillus salivarius strain isolated from the native duck gastrointestinal tract on the weight gain and serum immunoglobulins in broiler chickens suggested that the gastrointestinal bacteria of a species of poultry could be used as a probiotic in other types of poultry.