Quinolone and Organophosphorus Insecticide Residues in Bivalves and Their Associated Risks in Taiwan.

Bivalves, such as freshwater clams (Corbicula fluminea) and hard clams (Meretrix lusoria), are the most extensive and widely grown shellfish in land-based ponds in Taiwan. However, few studies have examined the contamination of bivalves by quinolone and organophosphorus insecticides. Thus, we adapted an established procedure to analyze 8 quinolones and 12 organophosphorus insecticides using liquid and gas chromatography-tandem mass spectrometry. Surveys in Taiwan have not noted high residual levels of these chemicals in bivalve tissues. A total of 58 samples of freshwater or hard clams were obtained from Taiwanese aquafarms. We identified 0.03 mg/kg of enrofloxacin in one freshwater clam, 0.024 mg/kg of flumequine in one freshwater clam, 0.02 mg/kg of flumequine in one hard clam, 0.05 mg/kg of chlorpyrifos in one freshwater clam, 0.03 mg/kg of chlorpyrifos in one hard clam, and 0.02 mg/kg of trichlorfon in one hard clam. The results indicated that 5.17% of the samples had quinolone insecticide residues and 5.17% had organophosphorus residues. However, the estimated daily intake (EDI)/acceptable daily intake quotient (ADI) indicated no significant risk and no immediate health risk from the consumption of bivalves. These results provide a reference for the food-safety screening of veterinary drugs and pesticides in aquatic animals. Aquatic products should be frequently screened for residues of prohibited chemicals to safeguard human health.

Emergence of Salmonella enterica serovar Potsdam as a major serovar in waterfowl hatcheries and chicken eggs.

Salmonellosis is a common food-borne illness in humans caused by Salmonella-contaminated poultry and their products. In hatcheries, 110 Salmonella isolates were identified, mostly from first enrichment, and few from delayed enrichment. The Salmonella prevalence in goose and duck hatcheries was higher when measured by four multiplex PCR methods than by traditional culture (73.8% vs. 44.35%, P < 0.05); 97.3% of 110 isolates were Salmonella Potsdam of serogroup C1 and other isolates were Salmonella Montevideo of C1 and Salmonella Albany of C2. Plasmid and pulsed field gel electrophoresis genetic analysis revealed that isolates from duck hatcheries were more diverse than those from goose hatcheries. In Salmonella Potsdam, host species-specific genotypes were observed in geese for genotypes 3, 4, and 5 and in ducks for genotypes 7, 8, and 9, suggesting that Salmonella Potsdam may evolve into goose- and duck-specific isolates. An examination of 1121 eggs found that only Salmonella Potsdam was identified in 1.8% (7/591) of eggs from chickens fed on the ground, not housed in cages, and in egg content (6/7) as well as eggshell membrane (1/7). In conclusion, Salmonella Potsdam may be a major Salmonella infection in waterfowl and chicken eggs.

Mirtazapine Reduces Adipocyte Hypertrophy and Increases Glucose Transporter Expression in Obese Mice.

Metabolic syndrome is known to engender type 2 diabetes as well as some cardiac, cerebrovascular, and kidney diseases. Mirtazapine-an atypical second-generation antipsychotic drug with less severe side effects than atypical first-generation antipsychotics-may have positive effects on blood glucose levels and obesity. In our executed study, we treated male high-fat diet (HFD)-fed C57BL/6J mice with mirtazapine (10 mg/kg/day mirtazapine) for 4 weeks to understand its antiobesity effects. We noted these mice to exhibit lower insulin levels, daily food efficiency, body weight, serum triglyceride levels, aspartate aminotransferase levels, liver and epididymal fat pad weight, and fatty acid regulation marker expression when compared with their counterparts (i.e., HFD-fed control mice). Furthermore, we determined a considerable drop in fatty liver scores and mean fat cell size in the epididymal white adipose tissue in the treated mice, corresponding to AMP-activated protein kinase expression activation. Notably, the treated mice showed lower glucose tolerance and blood glucose levels, but higher glucose transporter 4 expression. Overall, the aforementioned findings signify that mirtazapine could reduce lipid accumulation and thus prevent HFD-induced increase in body weight. In conclusion, mirtazapine may be useful in body weight control and antihyperglycemia therapy.

Epidemiological survey of Toxoplasma gondii and Neospora caninum infections in dairy goats in Central-Southern Taiwan.

Toxoplasma gondii and Neospora caninum are intracellular protozoan parasites that cause reproductive disorders in ruminants and humans. Information on the risk factors of T. gondii and N. caninum infections in goats is very limited in Taiwan. The aim of the study was to investigate the epidemiology and identify the risk factors of these two infections in goats. A total of 630 caprine sera were collected from 42 dairy goat farms and the owners were interviewed by a structured questionnaire. The apparent seroprevalences of T. gondii in farm- and individual- levels were respectively 88.1% and 32.22%, while those of N. caninum were 19.05% and 2.54%, respectively. Toxoplasma gondii B1 gene was identified in 7 feed samples and 8 from the water samples whereas N. caninum was not found. Wooden flooring was the main risk factor for T. gondii infection while the frequency of visits by staff to other farms and the breed of goat were risk factors for N. caninum. The improvement of flooring materials or thorough cleaning, periodic disinfection and maintenance of dryness on the floor are highly recommended for the prevention of T. gondii infection in farmed goats. In addition, unnecessary visits to other farms should be limited to prevent the spread of N. caninum. These factors should be highlighted for the prevention of T. gondii and N. caninum in goats, particularly when raised in intensive housing system with flooring on height.

Differential diagnosis of five avian Eimeria species by polymerase chain reaction using primers derived from the internal transcribed spacer 1 (ITS-1) sequence.

Chicken coccidia are protozoan parasites of the genus Eimeria. They cause economical losses in the poultry industry globally. The various species can be distinguished on the basis of the morphology of the oocysts and parasitic site in intestine, but these criteria sometimes are unreliable. Therefore, a species-specific polymerase chain reaction (PCR) was developed. Based on variable sequence regions, specific primers were constructed for the differentiation of five Eimeria species (Eimeria acervulina, E. brunette, E. maxima, E. necatrix, and E. tenella). PCR products were amplified from coccidian vaccine (coccivac-D and coccivac-B) and E. tenella and were subsequently sequenced. Similarities of the five species sequences between the vaccines and Genbank were 94-100%. Analysis of the E. tenella internal transcribed spacer 1 (ITS-1) partial sequence from Taiwan and from Genbank indicated that the similarity was 99.6%. The PCR sensitivity test of E. tenella in Taiwan is 50 oocysts. The five sets of primers will not amplify any non-specific bands of the chicken genome or its intestinal contents. Therefore, the five sets of specifically designed primers are guaranteed to be useful for differential diagnosis of avian coccidiosis caused by Eimeria spp.

Mycobacterium tuberculosis and M. bovis infection in Feedlot Deer (Cervus unicolor swinhoei and C. nippon taiouanus) in Taiwan.

BACKGROUND/PURPOSE: Mycobacterium bovis frequently infects wild and farm deer species with tuberculosis. This study investigated mycobacterial infection in two native deer species Cervus unicolor swinhoei (Formosan Sambar, Sambar) and C. nippon taiouanus (Formasan Sika, Sika). METHODS: Based on different sampling sources of 19 intradermal tuberculin test (ITT) Sambar, mycobacterial infection and/or species were detected by acid-fast stain, duplex polymerase chain reaction (PCR) and multiplex nested PCR (mnPCR) methods, traditional mycobacterial culture and gross lesion. Blood samples of 167 Sambar deer and 147 Sika deer were then tested by duplex PCR and mnPCR methods to investigate the prevalence of mycobacterial infection. Sequence variations of these mycobacterial species were analyzed as well. RESULTS: Duplex PCR and mnPCR assays could differentiate between MTBC (M. bovis and M. tuberculosis) and M. avium, as well as between M. bovis and M. tuberculosis, respectively. These PCR methods showed a higher detection rate than traditional culture and matched the gross lesions examined in 19 ITT-examined Sambar. Therefore, the mycobacterial infection in blood samples of 314 deer samples was detected using these PCR methods. Duplex PCR and mnPCR showed an identical prevalence of 16.1% in Sambar and 8.2% in Sika and a significant difference in prevalence between these two deer species. M. bovis and M. tuberculosis were the species detected in feedlot Sambar and Sika. M. tuberculosis was found only and first in Sambar fed in central Taiwan. Sequence analysis revealed diverse genetic variations in M. bovis and M. tuberculosis associated with deer subspecies. CONCLUSION: Multiplex PCR methods were established, and M. bovis and M. tuberculosis were identified in feedlot deer in Taiwan. Sequence variations indicated diverse sources of both mycobacterial species.