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31.
The interaction between cultured barber goby Elacatinus figaro (cleaner fish) and the dusky grouper Epinephelus marginatus, and the efficiency of the cleaner fish in removing ectoparasites were evaluated. When the interaction between these two species was observed, cleaner fish showed a preference for the largest groupers. In a second trial, treatments: TWC (Control) – two groupers without a cleaner fish, T1C – two groupers with one cleaner fish, T3C – two groupers with three cleaner fish and T6C – two groupers with six cleaner fish were tested in four replicates. After 8 days, monogeneans were removed and identified as Neobenedenia melleni. The highest mean abundance of parasites was found on the groupers in the TWC group (37 parasites per host) and the lowest on those in the T6C group (4.1 parasites per host). By increasing the number of cleaner fish, a higher cleaning efficiency was obtained, as observed in T6C, where almost 90% of the parasites were removed. Possibly, this removal would have been complete if the number of cleaners had not been reduced in the treatments due to the mortalities observed. This study demonstrates the possibility of using gobies to remove monogeneans and in improving grouper health.  相似文献   
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This review discusses the isolation, structural elucidation, and biological activities of halogenated indole alkaloids obtained from marine invertebrates. Meridianins and related compounds (variolins, psammopemmins, and aplicyanins), as well as aplysinopsins and leptoclinidamines, are focused on. A compilation of the 13C-NMR spectral data of these selected natural indole alkaloids is also provided.  相似文献   
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ObjectiveThe present study aimed to investigate the influence of methadone on cardiorespiratory parameters, electrocardiogram and clinical sedation in dogs. Further possible side effects are reported.Study designProspective experimental cross-over study.DogsEight, 1–4-year-old, various breeds of dogs of both genders weighing 9–36 kg.MethodsEach dog was treated three times: methadone 0.3 mg kg?1 (M0.3), 0.5 mg kg?1 (M0.5) and 1.0 mg kg?1 (M1.0) intramuscularly. Respiratory rate, heart rate and arterial blood pressure were recorded as well as electrocardiographic evaluation of lead II. Clinical sedation in each treatment received a score (0–3) after drug administration and at 30 minute intervals until scores and measurements returned to baseline values.ResultsA significant decrease in heart rate was seen with each dose of methadone and bradycardia (HR<60 bpm) was noted in a few dogs at each dose. A clinically significant arrhythmia occurred in one dog at 1 mg kg?1 that required reversal with butorphanol. There was no significant difference in SAP, MAP and DAP between treatments. Some side effects such as salivation, defecation, vocalization and panting, after administration of methadone were observed. There were no differences in mean values of heart rate, P-wave and QRS complex duration and QT interval between treatments.Conclusion and clinical relevanceMethadone administration was associated with panting and a decrease in heart rate at all doses tested in this study. The cardiac rhythm should be monitored carefully in dogs when methadone is administered on its own, especially at higher doses.  相似文献   
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ObjectiveTo compare two concentrations of ropivacaine administered for tumescent local anesthesia (TLA) in dogs undergoing mastectomy.Study designProspective randomized clinical study.AnimalsSeventeen bitches of various breeds, aged 12 ± 2 years and weighing 10 ± 6.5 kg requiring total unilateral or bilateral mastectomy.MethodsDogs were premedicated with acepromazine (0.04 mg kg?1) and morphine (0.4 mg kg?1) intramuscularly. Anesthesia was induced with propofol (2.5 mg kg?1) and midazolam (0.2 mg kg?1) intravenously, followed by intubation and maintenance with isoflurane and TLA. Dogs were randomly allocated to receive TLA either with 0.1% ropivacaine (group G1) or with 0.05% ropivacaine (group G05). TLA was performed by insertion of a multihole needle under the skin and infusion of ropivacaine and lactated Ringer’s solution at a fixed volume of 15 mL kg?1. Ropivacaine concentrations in arterial blood were measured by high-performance liquid chromatography. Post-operative pain was assessed using two scales (University of Melbourne pain scale and a modified composite measure pain scale) and von Frey filaments, 4 hours after TLA and at 1 hour intervals until sensitivity was regained. A score above 30% of the maximum possible score was considered a positive indicator of pain.ResultsPeak plasma concentrations of ropivacaine were measured 240 minutes after TLA in G1. Low concentrations were measured in G05 for 60 minutes, with subsequent increase. Analgesic rescue and return of sensitivity occurred at 7 ± 2.3 and 7 ± 1.9 hours (mean ± SD) after TLA for G1 and G05, respectively.Conclusions and clinical relevanceTumescent local anesthesia with ropivacaine provided satisfactory post-operative analgesia that lasted for several hours, with no difference in duration between the concentrations. No serious side effects were attributed to TLA. Results indicated that 0.05% ropivacaine provided adequate analgesia for mastectomy, however, more studies are required to support this conclusion.  相似文献   
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The objective of this study was to evaluate the effects of supplying the by-product of peach-palm (Bactris gasipaes) on performance and characteristics of carcass and non-carcass components of feedlot lambs. Twenty Santa Ines lambs of 150 days average age and 22.4?±?3.4 kg body weight were confined in individual pens. A completely randomized design was utilized with four experimental diets composed of: fresh peach-palm by-product enriched with urea, fresh peach-palm by-product + concentrate, silage of peach-palm by-product + concentrate, and silage of peach-palm by-product enriched with 15 % corn meal + concentrate. Intake was evaluated daily, and at the end of 42 days of experiments, lambs were slaughtered and the characteristics of carcass and non-carcass parts were evaluated. Performance and carcass characteristics showed differences between the animals’ intake of total mixed rations (TMR) and only the diet with roughage. For the lambs that intaked TMR, the form of utilization of roughage (fresh or as silage) affected animal performance but did not change the carcass characteristics. Dry matter intake and feed conversion were influenced by the form of utilization of the silage (with and without additive). Providing fresh by-product plus concentrate improves lamb performance but does not interfere in the carcass characteristics, compared with the use of by-product in the form of silage.  相似文献   
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Integrated aquaculture systems have the potential to enhance the environmental sustainability of aquaculture production, if economically feasible. Data from integrated tilapia-prawn production trials were used to develop economic-engineering enterprise budgets for ponds with and without substrate that targeted two different types of markets, using two production scales and two forms of land tenure. Inclusion of substrate increased investment and fixed costs and decreased net returns. Recreational markets (live tilapia for fee fishing and live prawns as bait) were profitable, but sales to supermarkets were not. Production scale and land tenure affected economic outcomes with increased pond size and leasing ponds demonstrating greater profitability. Results provide evidence of the need to carefully evaluate economic trade-offs associated with varying commercial-scale applications to increase the likelihood of adoption of new technologies.  相似文献   
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An indoor trial was conducted for 28 days to evaluate the effects and interactions of biofloc and seaweed Ulva lactuca in water quality and growth of Pacific white shrimp Litopenaeus vannamei in intensive system. L. vannamei (4.54 ± 0.09 g) were stocked in experimental tanks at a density 132 shrimp m?2 (566 shrimp m?3) and the U. lactuca was stocked at a density 0.46 kg m?2 (2.0 kg m?3). Biofloc with seaweed (BF-S) significantly reduced (P < 0.05) total ammonia nitrogen (TAN) by 25.9 %, nitrite–nitrogen (NO2–N) by 72.8 %, phosphate (PO 4 3 -P) by 24.6 %, and total suspended solids by 12.9 % in the water and significantly increased (P < 0.05) settleable solids by 34.2 % and final weight of shrimp by 6.9 % as compared to biofloc without seaweed. The BF-S can contribute by reducing nitrogen compounds (TAN and NO2–N), phosphate (PO 4 3 -P), and total suspended solids in water and increased final weight of shrimp.  相似文献   
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