Evaluation of Lactobacillus Species Isolated from Swine Intestine for their Probiotic Properties in Piglets

Intestinal mucosal scrapings (48) were collected from twelve, 6 month old, Large White Yorkshire pigs after slaughter. Isolates (23) that were gram positive rods, were alone subjected to physiological tests (growth at pH: 4.5, 9.5; temperature; 15, 45°C; and NaCl: 2, 6.5%), four isolates exhibited no growth at all conditions studied and were rejected. Biochemical tests on the remaining nineteen isolates showed them to be catalase negative, indicating that they belong to the genus Lactobacillus. Six of the isolates, which were oxidase and nitrate reduction positive, were rejected. Sugar fermentation tests performed on thirteen isolates, lead to speciation of two isolates as Lactobacillus acidophilus and Lactobacillus plantarum. Both these isolates were able to thrive at pH 2 and had significantly (P<0.05) highest growth at pH 5. L. plantarum revealed significantly (P<0.05) higher growth than L. acidophilus at all incubation hours, at pH 4, 5, 8 and 9. Both isolates showed, significantly (P<0.05) highest growth at bile concentration of 0.05%. At all bile concentrations and incubation hours studied, except 0.05 % bile at 10 hours incubation, L. plantarum revealed significantly (P<0.05) higher growth compared to L. acidophilus. Both the organisms revealed antimicrobial activity towards E. coli and Enterobacter sp., antimicrobial activity of L. acidophilus was significantly (P<0.05) higher compared to L. plantarum against E. coli. Freeze drying did not affect the viability of both organisms. Twenty four Large White Yorkshire piglets 42 days of age, with an average weight of 9.4 kg, were distributed randomly into four treatment groups; T1 without probiotic supplementation; T2 supplemented with L. acidophilus (1.0 x10 6 CFU/g of feed); T3supplemented with L. plantarum (1.0 x10 6 CFU/g of feed) and T4 supplemented with (L.plantarum1.0 x10 3 CFU/g andL.acidophilus1.0 x10 3 CFU/g of feed) and reared for 90 days. Average daily gain was significantly (P<0.1) highest (0.551 ± 0.148 kg) with significantly (P<0.05) lowest feed conversion ratio (2.373 ± 0.719) in T3 piglets. L. plantarumor L. acidophilus supplementation alone or in combination caused increased excretion of Lactobacilli and decreased excretion of E. coli in faeces, it had no impact on serum triglycerides but significantly (P<0.05) reduced total and LDL cholesterol and significantly (P<0.05) increased HDL cholesterol. Lactobacillus supplementation (T2, T3 and T4) caused significantly higher (P<0.05) villi width and crypt length and villi height was significantly higher (P<0.05) in T3 and T4. K e y w o r d s Lactobacillus acidophilus, Lactobacillus plantarum, Piglets, Probiotic, Feed conversion ratio, Serum cholesterol. Accepted: 28 August 2017 Available Online: 10 September 2017 Article Info Int.J.Curr.Microbiol.App.Sci (2017) 6(9): 3169-3183