A new Brucella canis species-specific PCR assay for the diagnosis of canine brucellosis

Brucellosis is a zoonotic disease that is transmitted from animals to humans, and the development of a rapid, accurate, and widely available identification method is essential for diagnosing this disease. In this study, we developed a new Brucella canis species-specific (BcSS) PCR assay and evaluated its specificity and sensitivity. A specific PCR primer set was designed based on the BCAN_B0548-0549 region in chromosome II of B. canis. The PCR detection for B. canis included amplification of a 300-bp product that is, not found on other Brucella species or, genetically or serologically related bacteria. The detection limit of BcSS-PCR assay was 6 pg/μl by DNA dilution, or 3 × 10³ colony-forming units (CFU) in the buffy coats separated from whole blood experimentally inoculated with B. canis. Using the buffy coat in this PCR assay resulted in approximately 100-times higher sensitivity for B. canis as compared to detect directly from whole blood. This is the first report of a species-specific PCR assay to detect B. canis, and the new assay will provide a valuable tool for the diagnosis of B. canis infection.     

Therapeutic trial of granulocyte-colony stimulating factor for dilated cardiomyopathy in three dogs

Three dogs were presented to us for evaluation of cardiac problems. Electrocardiographic recordings revealed severe tachyarrhythmia and atrial fibrillation with ventricular tachycardia in 2 of the 3 dogs. The echocardiographic findings of the 3 dogs revealed markedly decreased fractional shortening and a marked increase in E-point septal separation. Based on the results of electrocardiographic and echocardiographic evaluation, the 3 dogs were diagnosed as dilated cardiomyopathy (DCM). The dogs were treated with conventional cardiac medication, but cardiac function did not improve and the clinical signs remained. We subsequently attempted treatment with granulocyte-colony stimulating factor (G-CSF; 10 microg/kg, subcutaneously). The specific purpose of G-CSF therapy for DCM was to improve cardiac function and a significant improvement in cardiac function was confirmed. The three dogs had no treatment side effects. This case report suggests that G-CSF might have therapeutic effects for medically refractory DCM in dogs.     

An ecosystem-based assessment of the Korean blue crab trammel net fishery in the Yellow Sea and management implications

Landings in the blue crab, Portunus trituberculatus, fishery in Korean waters of the Yellow Sea have declined substantially from 11,000 t in the 1980s to 2,300 t in 2004. Blue crab habitat quality in the Yellow Sea has been degraded by anthropogenic activities including sand mining, land reclamation, and coastal pollution. Various traditional management measures have been implemented, including closed seasons during spawning and size limits, but these measures alone have been unsuccessful to conserve blue crab stocks. Consequently, a total allowable catch and a stock-rebuilding program using an ecosystem-based management approach were implemented in 2003 and 2006, respectively to rebuild blue crab stocks and restore habitats. This program involved assessment of both blue crab stock status and trammel-net fishery impacts at an ecosystem-level using an ecosystem-based fisheries assessment method ( [Zhang et al., 2009] and [Zhang et al., 2010]), which considered fishery data from catch and effort time-series, crab population biology, and ecosystem characteristics, including habitats and environmental conditions. Recent (2008) management status indices have shown significant positive change compared to conditions in 2000 with respect to sustainability of the stock and fishery and with regards to biodiversity and ecosystem habitat quality.     

Physicochemical Properties and In Vitro Starch Digestibility of Cooked Rice from Commercially Available Cultivars in Canada

The influence of amylose content, cooking, and storage on starch structure, thermal behaviors, pasting properties, and rapidly digestible starch (RDS), slowly digestible starch (SDS), and resistant starch (RS) in different commercial rice cultivars was investigated. Long grain rice with high‐amylose content had a higher gelatinization temperature and a lower gelatinization enthalpy than the other rice cultivars with intermediate amylose content (Arborio and Calrose) and waxy type (glutinous). The intensity ratio of 1047/1022 cm^–1 determined by Fourier Transform Infrared (FT‐IR), which indicated the ordered structure in starch granules, was the highest in glutinous and the lowest in long grain. Results from Rapid ViscoAnalyser (RVA) showed that the rice cultivar with higher amylose content had lower peak viscosity and breakdown, but higher pasting temperature, setback, and final viscosity. The RDS content was 28.1, 38.6, 41.5, and 57.5% in long grain, Arborio, Calrose, and glutinous rice, respectively, which was inversely related to amylose content. However, the SDS and RS contents were positively correlated with amylose content. During storage of cooked rice, long grain showed a continuous increase in pasting viscosity, while glutinous exhibited the sharp cold‐water swelling peak. The retrogradation rate was greater in rice cultivars with high amylose content. The ratio of 1047/1022 cm^–1 was substantially decreased by cooking and then increased during storage of cooked rice due to the crystalline structure, newly formed by retrogradation. Storage of cooked rice decreased RDS content and increased SDS content in all rice cultivars. However, no increase in RS content during storage was observed. The enthalpy for retrogradation and the intensity ratio 1047/1022 cm^–1 during storage were correlated negatively with RDS and positively with SDS (P ≤ 0.01).     

Comparative stomach contents and growth of the juvenile black seabream, Acanthopagrus schlegeli, reared in illuminated and unilluminated cages

The present study was designed to determine the positive effects of artificial illumination on the juvenile black seabream, Acanthopagrus schlegeli , by comparing stomach contents and growth between juveniles exposed to light and those maintained in the absence of light. The major prey items for juvenile black seabream reared in illuminated cages were amphipods (IRI%=50.5), copepods (IRI%=44.7) and polychaetes (IRI%=3.0), whereas those for the juveniles maintained in unilluminated cages were copepods (IRI%=96.0), amphipods (IRI%=3.4) and polychaetes (IRI%=0.6). The specific growth rates (SGR) of the juveniles reared in illuminated cages (0.99%) were significantly higher than those of the juveniles maintained in unilluminated cages (0.78%).     

Trophic structure in natural habitats of the abalone Haliotis discus hannai with distinct algal vegetation of kelp and crustose coralline algae: implication of ontogenetic niche shifts

The abundance, species composition, and stable isotope ratios of benthic organisms were investigated to determine the trophic structures in abalone (Haliotis discus hannai) habitats, which are characterized by contrasting vegetation of crustose coralline algae (CCA) and kelp beds. A size–frequency analysis revealed that juvenile abalones with shell lengths (SLs) smaller than ~30 mm primarily inhabited CCA beds, whereas adults were abundant in kelp beds. Stable isotope analyses indicated that CCA beds were composed of a single food chain, whereas kelp beds supported multiple food chains. The abalone were divided into three size groups to estimate potential species interactions during their ontogeny. A small gastropod, Homalopoma sangarense, was the most abundant species, but is suspected to be less competitive with abalone, especially in CCA beds. An abundant starfish Asterina pectinifera appeared to function as a potential predator of juvenile abalones in both CCA and kelp beds. We concluded that CCA beds are essential for immediate post-settlement processes of abalones, whereas kelp beds are more important for providing refuge and food sources for adult abalones. The present study highlights that ontogenetic niche shifting can be a successful life-history strategy to sustain the abalone population in a subtidal rocky shore ecosystem.     

An outbreak of fatal hemorrhagic pneumonia caused by Streptococcus equi subsp. zooepidemicus in shelter dogs

An outbreak of fatal hemorrhagic pneumonia with 70~90% morbidity and 50% mortality occurred in an animal shelter in Yangju, Gyeonggi Province, Korea. Clinically, the affected dogs showed severe respiratory distress within 48 h after arriving in the shelter. The dead were found mainly with nasal bleeding and hematemesis. At necropsy, hemothorax and hemorrhagic pneumonia along with severe pulmonary consolidation was observed, though histopathological analysis showed mainly hemorrhagic bronchopneumonia. Lymphoid depletion was inconsistently seen in the spleen, tonsil and bronchial lymph node. Gram-positive colonies were shown in blood vessels or parenchyma of cerebrum, lung, liver, spleen, and kidney. Also, Streptococcus (S.) equi subsp. zooepidemicus was isolated from the various organs in which the bacterium was microscopically and histologically detected. In addition, approximately 0.9 Kb specific amplicon, antiphagocytic factor H binding protein, was amplified in the bacterial isolates. In this study, we reported an outbreak of canine hemorrhagic bronchopneumonia caused by S. equi subsp. zooepidemicus in an animal shelter in Yangju, Korea.     

The efficacy of amoxicillin sodium against streptococcosis in cultured olive flounder Paralichthys olivaceus and its pharmacokinetics

The efficacy of amoxicillin sodium for controlling field and experimental Streptococcus iniae and S. parauberis infections in olive flounder (Paralichthys olivaceus) was evaluated after a single intramuscular administration. Furthermore, the minimal inhibitory concentrations (MIC) against 21 Streptococcus strains were determined. In addition, the pharmacokinetics and residue depletion in olive flounder were investigated. Single intramuscular doses of amoxicillin sodium at 20, 40, 80, and 160 mg/kg b.w. fish significantly reduced cumulative mortality rates to 18.8–31.3% (P < 0.05) for S. iniae and to 5.0–15.0% (P < 0.01) for S. parauberis, whereas the S. iniae‐ and S. parauberis‐infected positive control groups showed cumulative mortality rates of 68.8% and 60.0%, respectively. In a S. parauberis outbreak, amoxicillin sodium reduced the cumulative mortality rate to 7.5% and 4.8% at 20 and 40 mg/kg b.w. fish, respectively, whereas that of the untreated control group was 35.2%. Peak plasma concentrations (C_max) following a single intramuscular dose of 40 and 80 mg/kg b.w. fish were 62.64 (T_max, 1.59 h) and 87.61 (T_max, 3.02 h) μg/mL, respectively, with large AUC_0?t/MIC and C_max/MIC ratios, and sufficient T > MIC (time for maintaining plasma drug concentration greater than MICs) for S. iniae and S. parauberis. The estimated withdrawal period of amoxicillin sodium from muscle of olive flounder was about 8 days at 40 mg/kg b.w. fish (at 22 ± 1 °C). These results demonstrated a single intramuscular administration of amoxicillin sodium to be effective against streptococcosis in olive flounder.