Isolation and Characterization of Canine-specific Lactic Acid Bacteria from Fecal and Oral Samples of Dogs
G. Kalaiselvi *
Central University Laboratory, Centre for Animal Health Studies, Chennai -51, India.
R. Naveen Kumar
Sree Sastha Institute of Engineering and Technology, Chembarambakkam, Chennai- 600 123, India.
G. Balakrishnan
Central University Laboratory, Centre for Animal Health Studies, Chennai -51, India.
C. Soundararajan
Madras Veterinary College, Chennai -7, India.
N. Pazhanivel
Central University Laboratory, Centre for Animal Health Studies, Chennai -51, India.
*Author to whom correspondence should be addressed.
Abstract
Lactic acid bacteria constitute a major group of probiotic bacteria to be used as probiotic supplement for animals. The lactic acid bacteria are always species specific, but none of the commercial probiotic product of dogs are of canine origin. The isolation and characterization of lactic acid bacteria from canine fecal samples are important for preparation of species specific probiotic supplement. A total 160 numbers of Canine oral and fecal lactic acid bacteria Strains were isolated from 60 healthy dogs. Lactic Acid Bacteria were found in 37% of canine fecal samples and 9 % of canine oral samples. Then these samples were cultivated on lactobacillus selective media with acetic acid. The pro-biotic strains analysed based on the frequency and quantity in feces, growth density, acid tolerance antimicrobial activity, biochemical test and antibiotic sensitivity test. Among 160 fresh oral and fecal samples, 60 fecal samples and 15 oral samples were showed positive for lactic acid bacteria grown in lactobacillus selective media MRS broth and Rogosa agar. The 160 CFU / ml of culture were obtained by spread plate technique by using fresh fecal samples of healthy dogs but 10 CFU/ml obtained dogs which as having enteritis. The broad spectrum group of antibiotic used to check the antibiotic susceptibility and few of commonly used antibiotic have maximum zone of inhibition in probiotic culture. The isolates shows positive for catalase test, nitrate reduction test, citrate test. The lactic acid bacteria strain present in oral and fecal samples were identified by partial 16s rRNA gene sequencing of a fragment amplifier by PCR using universal primer. 900bp PCR product was obtained in 1% agarose gel. Lactobacillus fermentum, Lactobacillus plantarum, Lactobacillus casei, Lactobacillus mucosae, Lactobacillus delbrueckii and Lactobacillus salivarius were most frequently encountered bacteria in canine oral cavity and feces. Sequence similarity values of 93 % with Lactobacillus casei, 89% with Lactobacillus pentosus, 85% with Lactobacillus delbrueckii were found.
Keywords: Fecal and oral lactic acid bacteria, selective media, species specific, biochemical test