The genetic diversity of lactic acid producing bacteria in the equine gastrointestinal tract

Open Access
Publisher Website
Google Scholar
Abstract
Seventy-two lactic acid producing bacterial isolates (excluding streptococci) were cultured from the gastrointestinal tract of six horses. Two of the horses were orally dosed with raftilose to induce lactic acidosis and laminitis while the remaining four were maintained on a roughage diet. Near complete 16S rDNA was amplified by PCR from the genomic DNA of each isolate. Following RFLP analysis with the restriction enzymesMbo I,Hha I andHin fI, the PCR products from the 18 isolates that producedl- and/ord-lactate were subsequently cloned and sequenced. DNA sequence analysis indicated that the majority of the isolates were closely related to species within the genusLactobacillus, includingLactobacillus salivarius, Lactobacillus mucosae andLactobacillus delbrueckii. Four isolates were closely related toMitsuokella jalaludinii. Lactic acid producing bacteria (LAB) from the equine gastrointestinal tract was dominated by representatives from the genusLactobacillus, but also includedd-lactate-producing bacteria closely related toM. jalaludinii. Identification and characterization of LAB from the equine gastrointestinal tract should contribute to our understanding and management of fermentative acidosis, ulceration of the stomach and laminitis.