Characterization of the goldfish fecal microflora by the fluorescent in situ hybridization method

ABSTRACT:   Bacterial populations in goldfish feces were characterized by the fluorescent in situ hybridization (FISH) method. A total of nine different group-specific rRNA-targeted oligonucleotide probes were used. Approximately half of the microbial cells (57.8 ± 16.7%) were detected with a probe EUB338 and found to be bacteria. The microbial cells in 33–35 of the 35 samples from five specimens strongly hybridized with probes ALF1b, BET42a and GAM42a, suggesting that goldfish intestinal bacteria are mainly composed of α, β and γ-subclasses of Proteobacteria. The fact that a probe AER66 reacted with 25.6 ± 14.2% of the total microbial cells in all 35 samples, demonstrated that genus Aeromonas was the dominant species in the goldfish intestines. Genus Bacteroides including Bacteroides type A detected with a probe BAC303 was observed in 15 of 35 samples while other taxonomic groups determined with HGC69a, CF39a and P72 were detected in 6–11 of 35 samples. These results strongly suggest that Bacteroides shows the greatest daily fluctuation and interindividual variation in the intestines of goldfish. Moreover, the FISH method was proven to be useful for rapid enumeration of taxonomic groups of fish intestinal bacteria.     

Resistance of Venturia nashicola to thiophanate-methyl and benomyl: build-up and decline of resistance in the field

Changes in the proportion of benzimidazole-resistant strains in populations of Venturia nashicola were monitored in pear orchards. Successive applications of thiophanate-methyl increased the level of resistance in the populations. When the application of benzimidazoles was stopped and other fungicides were applied, the proportion of highly resistant strains gradually decreased and the proportion of intermediately resistant, weakly resistant and sensitive strains increased. It is suggested that this phenomenon is an example of genetic homeostasis within microbial populations.     

Antibacterial abilities of intestinal bacteria from larval and juvenile Japanese flounder against fish pathogens

The present study was undertaken to examine the antibacterial abilities of intestinal bacteria isolated from juveniles and larvae of Japanese flounder Paralichthys olivaceus . Newly hatched larvae of flounder were held in a 100 L plastic circular tank and fed rotifiers, Artemia nauplii and commercial feeds, depending on the developmental stage of the fish. Genera Aeromonas , Moraxella and Vibrio were predominantly isolated from the intestinal tracts of Japanese flounder at larval and juvenile stages, whereas Aeromonas , Bacillus , coryneforms, Moraxella , Pseudomonas and Vibrio were detected at high densities in live diets and artificial feeds. Antibacterial bacteria accounted for 1.7–24.3% of the intestinal isolates against Lactococcus garvieae , Pasteurella piscicida , Vibrio anguillarum and V. vulnificus . In particular, as much as 53.3% of Vibrio spp. other than Vibrio -swarmer isolated from 197-day-old juveniles inhibited the growth of P. piscicida . These results suggest that intestinal bacteria having antibacterial activity play a role in the prevention of infectious diseases.     

Evaluation of Low Level Laser Therapy on Primary Healing of Experimentally Induced Full Thickness Teat Wounds in Dairy Cattle

Objective —The purpose of this study was to evaluate the effect of low-level laser therapy (LLLT) on sutured wounds of the teat in dairy cattle.
Study Design —By using the Latin square design, the effect of LLLT was evaluated by radiography, measurement of microcirculation flow, histopathology, tensiometry, and hydroxyproline analysis.
Animals or Sample Population —Sixteen teats of four dairy cattle.
Methods —Full thickness wounds were made on the cranial surface of the teats. Teats were distributed into four groups; group A and B wounds were closed with a Gambee pattern, group C and D wounds were closed with three-layers of continuous suture pattern. Group B and D wounds were treated with 3.64 J/cm² of LLLT using a helium-neon system continuous wave (632.8 nm) output of 8.5 mW.
Results —The teat wall in non-LLLT groups was significantly thicker than in LLLT groups on day 7, 14 and 21. The mean blood flow differences between control and sutured sites in LLLT groups were significantly lower than those in non-LLLT groups. The morphology of the epidermis in LLLT groups more closely resembled the normal epidermis than that of non-LLLT groups. Collagen fibers in LLLT groups were denser, thicker, better arranged and more continuous with existing collagen fibers than those in non-LLLT groups. The mean tensile strength was significantly greater in LLLT groups than in non-LLLT groups.
Conclusion —The LLLT affects various aspects of the healing process, including minimizing inflammation, formation of edema, improvement of skin regeneration and enhancement of collagen synthesis.
Clinical Relevance —The LLLT could accelerate healing of sutured wounds of the teat in dairy cattle.