Branka Šeol

Records and genetic diversity of striped dolphins (Stenella coeruleoalba) from the Croatian coast of the Adriatic Sea

The striped dolphin (Stenella coeruleoalba) is a small, pelagic and cosmopolitan cetacean. Though it is the most common dolphin species in the Mediterranean Sea, it is not considered resident in the Croatian part of the Adriatic Sea. Fifteen striped dolphins were found dead in the Croatian part of the Adriatic Sea in the last eight years (1999– 2007). More specimens were found in southern than in the northern part of the Adriatic. Analysis of twelve microsatellite loci and sequencing of a 882 base pair (bp) fragment of the mitochondrial DNA (mtDNA) control region were performed for genetic characterization. The mean allelic diversity (7 ± 0.78) and mean expected heterozygosity haplotypes with 22 polymorphic sites in ten individuals. The haplotype diversity (0.911 ± 0.077) was high, while nucleotide diversity was strikingly low (0.006 ± 0.003). Results presented here support the notion of the striped dolphin not being resident species in Croatian part of the Adriatic Sea.

Antimicrobial susceptibility of Pseudomonas aeruginosa isolates from dogs with otitis externa

Pseudomonas aeruginosa is a common cause of otitis externa in dogs, and treatment of these infections is becoming problematic because of the increasing number of multiresistant strains. The aim of the present study was to compare the in vitro activities of cefepime, ceftazidime, enrofloxacin, ciprofloxacin, gentamicin and ticarcillin/clavulanic acid against 104 strains of P aeruginosa isolated from dogs with otitis externa. Antimicrobial susceptibility and minimum inhibitory concentrations, in µg/ml, were evaluated by the E test (bioMérieux). The most active compound was ceftazidime, with 100 per cent efficiency. The majority of tested strains were susceptible to ticarcillin/clavulanic acid (89.4 per cent), followed by ciprofloxacin (88.5 per cent) and cefepime (60.6 per cent). The highest resistance was observed to enrofloxacin (51.9 per cent) and gentamicin (43.3 per cent). Large numbers of strains were intermediately susceptible to antibiotics registered for use in veterinary medicine in Croatia – enrofloxacin (47.1 per cent) and gentamicin (41.3 per cent).

Epidemiological and microbiological study of an outbreak of infectious keratoconjunctivitis in sheep.

After several thousand sheep had been imported from Australia and New Zealand to Croatia during 1995, many native sheep that had been in contact with the imported animals acquired a severe ocular disease closely resembling infectious keratoconjunctivitis. In affected flocks glucose-fermenting mycoplasma were isolated from 48 per cent of conjunctival swabs and Branhamela ovis from 58 per cent. Twelve of 42 culturally and biochemically identical isolates were identified as Mycoplasma conjunctivae by polymerase chain reaction. From the conjunctivae of two animals M conjunctivae and M arginini were isolated in mixed culture. For many reasons most farmers removed the imported animals from their flocks and only sporadic cases of the disease were recognised in 1996. At the end of 1997, six flocks which were clinically free of the disease but had been affected during 1995, and five flocks with no history of the severe ocular disease were examined clinically and microbiologically, and were found to be free of M conjunctivae infection. At the time, B ovis was cultured almost exclusively from sheep originating from flocks which had been affected during 1995 and/or 1996. It was usually isolated in pure culture or as the predominant bacterial species, and was often accompanied by mild conjunctivitis. There were no microbiologically confirmed new cases of infectious keratoconjunctivitis during 1998 and 1999.

Susceptibility to Antimicrobial Agents of Streptococcus suis Capsular Type 2 Strains Isolated from Pigs

The minimal inhibitory concentrations (MICs) for thirty-three epidemiologicaly unrelated clinical isolates of Streptococcus suis capsular type 2 were determined in relation to ampicillin, ampicillin-sulbactam, amoxicillin, clavulanate-amoxicillin, penicillin G, cephalexin, gentamicin, streptomycin, erythromycin, tylosin and doxycycline, using the microtitre broth dilution procedure described by the U.S. National Committee for Clinical Laboratory Standards (NCCLS). Gentamicin was the most active compound tested, with an MIC for 90% of the strains tested (MIC(90)) of 0.4 mg/L. Overall, 70% of strains were resistant to doxycycline (MIC(90) > or = 100.0 mg/L), followed by penicillin G (51% of strains) (MIC(90) + or = 100.0 mg/L). Resistance to amoxicillin and ampicillin was 36.4% (MIC(90) 12.5 mg/L) and 33.3% (MIC(90) 50.0 mg/L), respectively. 15.2% of S. suis strains were resistant to streptomycin, tylosin and cephalexin with MIC90 values of 25.0 mg/L, 12.5 mg/L and 25.0 mg/L, respectively. A combination of ampicillin and sulbactam (MIC(90) 6.3 mg/L) and a combination of amoxicillin and clavulanate (MIC(90) 3.1 mg/L) as well as erythromycin (1.6 mg/L) were of the same efficacy, with a total of 9.1% resistant S. suis strains. This high percentage of resistance to doxycycline and penicillin G precludes the use of these antibiotics as empiric therapy of swine diseases.

Outbreak of Salmonella Enteritidis and isolation of Salmonella Sofia in chinchillas (Chinchilla laniger)

The paper describes and outbreak of Salmonellosis in chinchilla caused by Salmonella enteritidis and S. sofia.

In vitro cultivation of porcine limbal stem cells

Abstract Similarly as in other organ structures stem cells are present in cornea residing basal epithelial layer termed palisade of Voight. A growing interest in allografts and xenografts implies a thorough study of regenerative potentials of these cells, as well as a clear description of their patterns in in vitro tissue cultures to be grafted. Recently we have developed a simple method for cultivation of porcine corneal epithelial stem cells obtained by biopsy from the limbal region. Eight enucleated eyes were obtained from four slaughtered pigs. 5 mm2 samples of limbal epithelium were taken by keratotomy method. The primary cultures of these cells showed phenotypic and morphometric characteristics of porcine corneal epithelial cells following May-Grunwald-Giemsa staining. After 5d of sowing they reached 80% of confluence. With the «Night & Day» lenses a total confluence was achieved 5d earlier in comparison to the cells that were grown in the secondary cultures. Accordingly, the use of porcine limbal stem cells has potentials in veterinary medicine (as novel approach in reparative/regenerative medicine of pets, horses and selected breeds), but also are in accordance with the extensive studies on the potential use of xenografts, mainly swine tissues/organs, in humans.

Isolation of Clostridium tertium from a Striped Dolphin (Stenella coeruleoalba) in the Adriatic Sea

Bacteriologic examination of an abscess found between blubber and musculature of a striped dolphin (Stenella coeruleoalba) found dead on 30 March 2002 in the Adriatic Sea, Croatia, was performed and an aerotoler-ant, nontoxogenic Clostridium tertium was isolated in pure culture. National Collections of Industrial Food and Marine Bacteria (NCIMB Ltd., Aberdeen, Scotland, UK) confirmed the results. Sequencing results showed it to be C. tertium with 100% similarity. The strain was named Clostridium tertium strain Zagreb, acceded to the culture collection and assigned the accession number NCIMB 13970. This is the first record of C. tertium in marine mammals.