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71.
Boysen SR Rozanski EA Chan DL Grobe TL Fallon MJ Rush JE 《Journal of the American Veterinary Medical Association》2002,221(10):1441-4, 1420
Mycotoxins are fungal metabolites that induce undesirable effects. The effects of these mycotoxins vary depending on the chemical structure of the toxin and degree of toxicity. Mycotoxins that induce muscle tremors, ataxia, and convulsions are termed tremorgenic mycotoxins. Our report documents the clinical course of 4 dogs from a single household that were simultaneously affected by tremorgenic mycotoxins. Diagnosis of tremorgenic mycotoxicosis was confirmed by stomach content analysis from 1 of the dogs. The mycotoxins identified were penitrem A and roquefortine, which are both produced by Penicillium spp. Treatment goals following tremorgenic mycotoxin ingestion include minimizing absorption, controlling tremors and seizures with methocarbamol and pentobarbital sodium administration, and providing supportive care. Two of the affected dogs required ventilatory support. With early aggressive treatment, prognosis is good and recovery is complete without sequelae. It is helpful for the clinician to be familiar with the typical clinical signs at the time of admission, treatment, and clinical course of dogs with tremorgenic mycotoxicosis. 相似文献
72.
Barber D Campbell J Davey J Luke T Agren E Beveridge I 《Australian veterinary journal》2008,86(1-2):64-66
An adult male Eastern Grey kangaroo from a wildlife reserve near Melbourne was submitted for necropsy examination and was discovered to have abnormal dentition. There was no evidence that any premolars or molars had ever been present on the right mandible, whilst the incisors were normal. The age of the kangaroo was estimated to be 1 year 9 months using the right maxillary molars and 2 years 4 months old using the contralateral side, presumably due to the asymmetry of the dental arcades. 'Lumpy jaw', a common periodontal disease of kangaroos, from which Bacteroides sp was cultured, was present on the base of the vertical ramus of the left mandible. Complete unilateral absence of premolar and molar teeth in the mandible of a kangaroo has not been described. This condition affected molar progression in both sets of maxillary molars. 相似文献
73.
Hearn Andrew J. Cushman Samuel A. Goossens Benoit Ross Joanna Macdonald Ewan A. Hunter Luke T. B. Macdonald David W. 《Landscape Ecology》2019,34(2):275-290
Landscape Ecology - The Sunda clouded leopard is vulnerable to forest loss and fragmentation. Conservation of this species requires spatially explicit evaluations of the effects of landscape... 相似文献
74.
Samantha Bui Frode Oppedal Velimir Nola Luke T. Barrett 《Journal of fish diseases》2020,43(6):697-706
Problematic sea lice infestations on farmed Atlantic salmon (Salmo salar) have motivated extensive research and development into new methods to prevent, monitor and control sea lice. Most of these technologies require detailed information on the behaviour, spatial distribution and demography of lice on host fish. This study investigated how salmon lice (Lepeophtheirus salmonis) infestation density varies across the host's surface under sea cage farming conditions. Lice abundance, demography and attachment location were tracked over time, with repeated sampling of 300 individually tagged salmon across three replicate experimental sea cages. The data reveal clear differences in attachment locations according to sex and stage, but with an overall preference for the dorsal surface among mobile stages—dorsal head for adult females and dorsal-posterior section for males and pre-adults. Total lice abundance was highly variable between repeated measures of individual fish, consistent with frequent host-switching or mortality. Total lice numbers also declined between sampling dates, likely due to handling, with lost mobile lice being almost exclusively adult males. As the distribution of sea lice on hosts is likely determined by numerous factors, future image-based automated detection systems should be validated in settings that reflect the complex host–parasite interactions that occur in open farming systems. 相似文献
75.
Timothy J. Bruce Jie Ma Luke P. Oliver Evan M. Jones Benjamin R. LaFrentz Kenneth D. Cain 《Journal of fish diseases》2020,43(8):839-851
Burbot (Lota lota maculosa) are a potential new species for commercial aquaculture. As burbot culture expands, there is a need to further define pathogen susceptibility and characterize aspects of the burbot immune response in an effort to assess fish health. A recent clinical diagnostic case from juvenile burbot reared at a commercial production facility resulted in the isolation and identification of Flavobacterium columnare along with several Aeromonas spp. The F. columnare isolate was assigned to genetic group 1 via multiplex PCR, a genetic group commonly associated with columnaris disease cases in rainbow trout (Oncorhynchus mykiss). Virulence of the F. columnare isolate was assessed in vivo in both juvenile burbot and rainbow trout. Additionally, several of the Aeromonas sp. case isolates were identified via sequencing (16S rRNA, gyrB and rpoD) and a putative A. sobria isolate (BI-3) was used to challenge burbot, along with a known virulent Aeromonas sp. (A141), but BI-3 was not found to be virulent. Burbot were refractory to F. columnare when challenged by immersion, and it is likely that this is a secondary pathogen for burbot. Although refractory in burbot, the identified F. columnare isolate (BI-1) was found to be virulent in rainbow trout. 相似文献
76.
Harsha S.C. Galkanda‐Arachchige Luke A. Roy Donald Allen Davis 《Aquaculture Research》2020,51(9):3540-3550
Pacific white shrimp, Litopenaeus vannamei, exhibit a remarkable ability to tolerate low‐salinity environments, facilitating its culture far from coastal areas using various production systems at salinities less than 15 g/L. Recirculating aquaculture systems (RAS) and biofloc systems are usually operated using reconstituted sea salt (RSS), which is a considerable financial burden to commercial producers due to its higher price. Current study was carried out with the objective of testing the efficacy of a low‐cost salt solution to replace expensive RSS to grow shrimp under laboratory conditions. Low‐cost salt mixture (LCSM) was formulated to yield sodium, potassium, calcium and magnesium concentrations closely comparable to that of diluted seawater using agriculture grade sodium chloride, magnesium chloride, magnesium sulphate, potassium oxide, calcium chloride and sodium bicarbonate. Growth trials were conducted at three different salinities of 3, 6 and 15 g/L, incrementally replacing RSS with LCSM (0, 2.5, 25, 50, 75 and 100%) at four replicates per treatment. Twenty juvenile shrimp were reared for 42 days in 150 L polyethylene tanks. Ionic profile of water, ionic profile and osmolality of shrimp haemolymph were determined to justify growth and survival data through analysing ionic variations and osmoregulatory capacity of shrimp. At the conclusion, no significant differences were observed in survival, growth, osmoregulation and levels of cations in shrimp haemolymph between RSS and LCSM treatments at all salinities examined. Results reflect the potential use of LCSM to replace RSS which could be an excellent solution to bring down the cost of production in inland shrimp aquaculture. 相似文献
77.
78.
Jingping Guo Ying Huang Guillaume Salze Luke A. Roy Donald Allen Davis 《Aquaculture Nutrition》2020,26(2):225-232
Two feeding trials were conducted to investigate the effect of replacing fishmeal with a combination of soy and corn protein concentrate (1:1 ratio) on growth performance of the Pacific white shrimp (Litopenaeus vannamei). A basal diet containing 200 g/kg fishmeal was systematically reduced (200, 150, 100, 50 and 0 g/kg) with protein concentrate on an isonitrogenous basis. Additionally, two diets containing 0 or 50 g/kg fishmeal were supplemented with lysine and methionine to evaluate possible limitations in EAAs. Each diet was randomly fed to five replicate tanks (15 shrimp per 75 L aquaria) reared in an indoor clear water system (Trial 1), or four replicate circular tanks (100 shrimp per 800 L) reared in outdoor green water system (Trial 2). In trial 1, results indicated a slight decrease in shrimp performance as fishmeal was replaced at the highest levels. Meanwhile, the supplementation of lysine and methionine to the diets did not result in shifts in survival, growth or FCR. In trial 2, there were no significant differences in growth performance across the tested diets. This study demonstrated that plant‐based protein concentrates can be used to replace fishmeal in practical shrimp diet in clear and green water under high stocking density. 相似文献
79.
Jie Ma Timothy J. Bruce Luke P. Oliver Kenneth D. Cain 《Journal of fish diseases》2019,42(7):1065-1076
Co‐infection of rainbow trout with infections haematopoietic necrosis virus (IHNV) and Flavobacterium psychrophilum is known to occur, and it has been speculated that a combined infection can result in dramatic losses. Both pathogens can persist in fish in an asymptomatic carrier state, but the impact of co‐infection has not been well characterized or documented. In this study, it was hypothesized that fish co‐infected with F. psychrophilum and IHNV would exhibit greater mortality than fish infected with either pathogen alone. To test this, juvenile rainbow trout were co‐infected with low doses of either IHNV or F. psychrophilum, and at 2 days post‐initial challenge, they were given a low dose of the reciprocal pathogen. This combined infection caused high mortality (76.2%–100%), while mortality from a single pathogen infection with the same respective dose was low (5%–20%). The onset of mortality was earlier in the co‐infected group (3–4 days) when compared with fish infected with F. psychrophilum alone (6 days) or IHNV (5 days), confirming the synergistic interaction between both pathogens. Co‐infection led to a significant increase in the number of F. psychrophilum colony‐forming units and IHNV plaque‐forming units within tissues. This finding confirms that when present together in co‐infected fish, both pathogens are more efficiently recovered from tissues. Furthermore, pathogen genes were significantly increased in co‐infected groups, which parallel the findings of increased systemic pathogen load. Extensive tissue necrosis and abundant pathogen present intracellularly and extracellularly in haematopoietic tissue. This was pronounced in co‐infected fish and likely contributed to the exacerbated clinical signs and higher mortality. This study provides novel insight into host–pathogen interactions related to co‐infection by aquatic bacterial and viral pathogens and supports our hypothesis. Such findings confirm that mortality in fish exposed to both pathogens is greatly elevated compared to a single pathogen infection. 相似文献
80.
Pressurized liquid extraction (PLE) was used to extract anthocyanins from the freeze-dried skin of a highly pigmented red wine grape with six solvents at 50 degrees C, 10.1 MPa, and 3 x 5 min extraction cycles. Temperature (from 20 to 140 degrees C in 20 degrees C increments) effects on anthocyanin recovery by acidified water and acidified 60% methanol were also studied. Acidified methanol extracted the highest levels of total monoglucosides and total anthocyanins, whereas the solvent mixture (40:40:20:0.1 methanol/acetone/water HCl) extracted the highest levels of total phenolics and total acylated anthocyanins. Acidified water extracts obtained by PLE at 80-100 degrees C had the highest levels of total monoglucosides, total acylated anthocyanins, total anthocyanins, total phenolics, and ORAC values. Acidified methanol extracts obtained by PLE at 60 degrees C had the highest levels of total monoglucosides and total anthocyanins, whereas extracts obtained at 120 degrees C had the highest levels of total phenolics. High-temperature PLE (80-100 degrees C) using acidified water, an environmentally friendly solvent, was as effective as acidified 60% methanol in extracting anthocyanins from grape skins. 相似文献