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Aquaculture, one of the most important food production practices worldwide, faces serious challenges of mitigating the detrimental impacts of intensive farming on the environment and increased prevalence of antibiotic resistance. To develop an environment-friendly aquaculture system, a land-based and farm-scale sequentially integrated multi-trophic aquaculture (IMTA) system was established for farming Chanos chanos in southwestern Taiwan. In this system, fishes are cultured in combination with organic extractive shellfish and inorganic extractive seaweed. This study aimed to evaluate the prevalence of sulfonamide-resistant bacteria, microbial community structure, and occurrence of sulfonamide resistance genes in the IMTA and traditional aquaculture systems. Water and sediment samples were collected before raising and after harvesting C. chanos. Our results showed that the occurrence of sulfonamide-resistant phenotypes in the IMTA system was comparable with that in influent seawater, while the traditional system exhibited a high sulfonamide resistance rate. Additionally, the traditional system resulted in a deviation of the bacterial community structure from that of seawater. In the water samples from the IMTA system and influent seawater, Proteobacteria and Bacteroidetes were the two dominant phyla, representing approximately 75% and 15% of the community, respectively. In the traditional system, Actinobacteria, constituting 39% of the community, was the dominant bacterial phylum. Thirty-one sulfonamide-resistant bacterial species were isolated. In conclusion, a sequentially IMTA system showed superior ability to maintain the prevalence of antibiotic resistance and the integrity of the bacterial community structure compared to the traditional farming system, representing a potentially valuable aquaculture system for preserving the sustainability of the marine environment.

Traditional methods to combat disease with antimicrobial agents in aquaculture have caused serious concern and alternative approaches using probiotics have been sought. A photosynthetic purple sulfur bacteria Marichromatium purpuratum RuA2 that thrives at salt concentrations of 0.5% to 5.0% and has a more temperate tolerance for oxygen was isolated from a marine fish pond located on the southwestern shore of Qigu, Taiwan. The effects of M. purpuratum RuA2 on the water quality parameters, the occurrence of the sulfonamide resistance gene sul1 and the microbial community were investigated in situ. Supplementation with strain RuA2 resulted in an increased removal rate of total organic carbon and nitrate ions, as well as a lower occurrence of sul1, in the bacterial community. The abundance and diversity of the bacterial community in the control and M. purpuratum RuA2-supplemented water samples were investigated. Proteobacteria, Bacteroidetes, Cyanobacteria, Actinobacteria and Planctomycetes were identified to be the top five predominant phyla in the control and M. purpuratum RuA2-supplemented water samples. However, supplementation with M. purpuratum RuA2 increased the diversity of the bacterial community composition. Fourteen unique genera were detected solely in strain RuA2-supplemented water samples and the relative abundance of seven shared genera was associated with supplementation with strain RuA2. In conclusion, M. purpuratum RuA2 showed a desirable capacity for improving water quality, reducing the occurrence of the resistance gene sul1 and advantageous effects on the microbial community structure. Tolerant to salinity and oxygen, M. purpuratum RuA2 exhibits an attractive potential for resolving the challenges facing aquaculture today.

Wastewater effluent from aquaculture ponds can affect aquatic ecosystems. To mitigate this problem, we designed 2 sets (southern and northern) of land-based and farm-scale sequential integrated multi-trophic aquaculture (IMTA) systems in order to reduce water pollution and to diversify and optimize aquaculture products in coastal southern Taiwan. In each system, the 1st pond cultivated milkfish as the main aquaculture product, the 2nd pond cultivated Portuguese oysters as the product to reduce suspended particles, and the 3rd pond cultivated the seaweed Gracilaria sp. as feed and to absorb nutrients. Photosynthetic bacteria (PSB) were added to the southern system in order to reduce nutrients. The objective of this study was to evaluate and compare performance parameters of the compartments and the overall IMTA systems preliminarily. Our results showed that the southern system with the addition of PSB had lower PO4−3-P, slightly higher turbidity, and higher brown algal biomass than the northern system. In the southern system, PO4−3-P and cyanobacteria levels were lowest at the end of the seaweed pond. In the northern system, NO2−-N and phytoplankton levels were lowest at the end of the seaweed pond. Turbidity was reduced in the oyster pond and further reduced in the Gracilaria pond in both systems. The high seaweed yield in the northern system indicated substantial nutrient absorption. Advantages and limitations in terms of water purification and aquaculture production of these IMTA systems are evaluated in the present paper.

isolates being Methicillin-Resistant Coagulase-Negative Staphylococci (15.0%) and Methicillin-Susceptible Coagulase-Negative Staphylococci (15.0%), followed by gram-negative isolates (n Z16; 40.0%),and Candida spp. (n Z 6; 15.0%). Conclusions: In conclusion, the incidence of CRBSI in gastrointestinal surgery revealed a non-ICU, high-risk sector that needs further investigation. Detectection of risk factors and pathogenesis of CRBSI in patients undergoing gastrointestinal surgery was expected to provide better prevention measures to reduce CRBSI in non-ICU.

In the present study, attempts were made to clarify the effect of heavy metal stressors and salinity shock on the disease susceptibility of grouper fry (Epinephelus sp.) to infectious pancreatic necrosis virus (IPNV) infection. Zinc, cadmium and copper (5 ppm ZnCl2, 3 ppm CdCl2 and 1 ppm CuCl2) were used to treat groupers before and after virus infection. Cumulative mortalities in the experimental groups were 96-100% within 42 days. Only 5-15% mortalities were observed in most of the groups that were exposed to either heavy metals or virus infection alone. Subsequently, virus was re-isolated from the experimentally infected groupers, and copper concentration was measured in fish that had been exposed to CuCl2. We also investigated the effect of salinity shock (i.e. an abrupt change of salinity level from 33 ppt to either 40 ppt or 20 ppt) on susceptibility of grouper to IPNV. Similar results were obtained, mortalities of groupers in the experimental groups reached 80-100%. The results of the present study suggest that an IPN virus with only low pathogenicity could cause high mortality in groupers when combined with environmental stress.

The hard clams (Meretrix lusoria) that are cultured in Taiwan have suffered high mortalities each spring and/or summer since 1969. Environmental factors, pollution and infectious diseases have been implicated, but no single factor has been shown to lead directly to large-scale death of the cultured hard clam. In the present study, attempts were made to examine the effects of heavy metals on the susceptibility of the hard clam to birnavirus infection. First we determined the stability of the clam birnavirus in sea, brackish, fresh waters at 4, 15 and 26°C and in solutions containing different concentrations of Zn2+, Cd2+, Cu2+, and Hg2+. For each heavy metal cation, two concentrations which had no influence on clam birnavirus infectivity were selected and used to treat the hard clams before and after virus infection. In experiment I, clams were immersed in 105.0 TCID50 /ml virus solution for 24 h and subsequently exposed to one of the heavy metals. Cumulative mortalities of clams were 20∼52% in most experimental groups although mortalities reached 91% in infected clams exposed to high concentrations of copper. In experiment II, groups of 60 clams were exposed to one of the heavy metals for 7 days and then infected with the virus, while controls were only expose to heavy metals. Mortalities of clams in the experimental groups reached 65∼90% within 28 days, while only 10% mortalities were observed in the groups that were exposed to either heavy metals or virus infection alone.

Two full-length cDNA sequences encoding a crustacean hyperglycemic hormone (CHH) precursor were cloned from tissues of the mud crab Scylla olivacea. Sco-CHH (S. olivacea CHH) was cloned from eyestalk ganglia, whereas Sco-CHH-L (S. olivacea CHH-like peptide) was cloned from extra-eyestalk tissues (pericardial organ and thoracic ganglia). Each conceptually translated precursor is expected to be processed into a signal peptide, a CHH precursor-related peptide (CPRP), and a mature CHH or CHH-like peptide. The two precursors are identical in amino acid sequence through the 40th residue of the mature peptide, but different from each other substantially in the C-terminus. Both CHH variants contain the six highly conserved cysteine residues characteristic of the CHH family peptides, and share higher sequence identities with other brachyuran CHH sequences than with those of other taxonomic groups. As determined by reverse transcription-polymerase chain reaction (RT-PCR), the transcripts of Sco-CHH and Sco-CHH-L were present in eyestalk ganglia and several extra-eyestalk tissues (the thoracic ganglia, pericardial organ, brain, circumesophageal connectives, and gut). Sco-CHH was the predominant form in eyestalk ganglia, while Sco-CHH-L was the predominant form in several extra-eyestalk tissues. Neither transcript was expressed in the muscle, hepatopancreas, ovary, testis, heart, or gill. Antisera were raised against synthetic peptides corresponding to a stretch of sequence-specific to the C-terminus of Sco-CHH or Sco-CHH-L. Western blot analyses of tissues expressing Sco-CHH and Sco-CHH-L detected a Sco-CHH immunoreactive protein in the sinus gland, and a Sco-CHH-L immunoreactive protein in the pericardial organ. Immunohistochemical analyses of the eyestalk ganglia localized both Sco-CHH and Sco-CHH-L immunoreactivity to the sinus gland, and only Sco-CHH immunoreactivity to the X-organ somata; analyses of the pericardial organs also localized both Sco-CHH and Sco-CHH-L immunoreactivity to the anterior and posterior bars, as well as to longitudinal trunks joining the two bars. The combined data provided supporting evidence that Sco-CHH and Sco-CHH-L are co-localized in the same tissue.

This study was conducted to evaluate nursing intervention to enhance the efficacy of a home-based pelvic floor muscle exercise (PFME) in treating mixed urinary incontinence among a community-based population. Eighty-eight women with mixed incontinence were recruited for this study and were asked to practice PFME at home as instructed. A registered nurse monitored the study group via telephone checkups twice a week. The Symptoms (LUTS) Questionnaire and a disease-specific questionnaire of impact index were used for repeat measurements before intervention, at 3 and 6 months after PFME. Symptoms such as frequency, nocturia, urge incontinence, and urinary stress incontinence improved significantly in the study group at 6 months. Quality of life with regard to worry about pads/towels leakage and getting wet also improved in the study group at 6 months. Nursing intervention can significantly improve the efficacy of a home-based PFME program in community women with mixed storage symptoms.