title: Aerobic oral and rectal bacteria of free-ranging Steller sea lion pups and juveniles (Eumetopias jubatus) in Alaska.
abstract: Bacteriologic cultures from oral, rectal, and lesion samples from free-ranging Steller sea lion (SSL, Eumetopias jubatus) pups and juveniles in Alaska (2001-2005) were examined to determine frequency of infection by a specific subset of common and pathogenic aerobic bacteria. Associations between isolated bacteria and age, sex, body condition, location, and sampling season were investigated. Salmonella spp. isolates were further evaluated to determine spatial clustering (n=48) and to identify serovars (n=13) and antimicrobial susceptibility patterns (n=11). We sampled 356 SSL pups (n=272) and juveniles (n=84), and identified 988 isolates of 13 bacterial genera of specific interest. Pasteurella spp. (43.8%), beta-hemolytic Streptococcus spp. (30.6%), and Mannheimia spp. (18.2%) were the most commonly isolated oral bacteria (n=499 isolates), whereas Escherichia coli (47.6%), beta-hemolytic E. coli (32.4%), Salmonella spp. (10.4%), and Campylobacter spp. (7.8%) were the most frequently isolated rectal bacteria (n=460 isolates). Salmonella was most commonly found in pups from western stocks and in samples collected during fall/winter seasons. A significant Salmonella cluster was detected at the Perry Island haulout. Five serovars were isolated: Enteritidis, Infantis, Newport, Reading, and Stanley. Pulsed-field gel electrophoresis provided evidence that Salmonella isolates were most likely being maintained within the SSL population in Alaska.
authors.affiliation: Wildlife Health Center, School of Veterinary Medicine, University of California, Davis, One Shields Avenue, Davis, California 95616, USA. secarrasco@ucdavis.edu
authors.forename: Sebastian E
authors.initials: SE
authors.lastname: Carrasco
authors.forename: Kathleen A
authors.initials: KA
authors.lastname: Burek
authors.forename: Kimberlee B
authors.initials: KB
authors.lastname: Beckmen
authors.forename: J Lindsay
authors.initials: JL
authors.lastname: Oaks
authors.forename: Margaret A
authors.initials: MA
authors.lastname: Davis
authors.forename: Katherine N K
authors.initials: KN
authors.lastname: Baker
authors.forename: Jonna A K
authors.initials: JA
authors.lastname: Mazet
mesh_terms: D000367:Age Factors; D000413:Alaska / Q000453:epidemiology; D000818:Animals; D000831:Animals, Newborn; D000835:Animals, Wild; D005260:Female; D008297:Male; D009055:Mouth / Q000382:microbiology*; D012007:Rectum / Q000382:microbiology*; D012475:Salmonella / Q000145:classification / Q000302:isolation & purification*; D012481:Salmonella Infections, Animal / Q000453:epidemiology*; D046070:Sea Lions / Q000382:microbiology*; D012621:Seasons; D012737:Sex Factors; D013045:Species Specificity