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41.
Assessment of melamine and cyanuric acid toxicity in cats. 总被引:30,自引:0,他引:30
Birgit Puschner Robert H Poppenga Linda J Lowenstine Michael S Filigenzi Patricia A Pesavento 《Journal of veterinary diagnostic investigation》2007,19(6):616-624
The major pet food recall associated with acute renal failure in dogs and cats focused initially on melamine as the suspect toxicant. In the course of the investigation, cyanuric acid was identified in addition to melamine in the offending food. The purpose of this study was to characterize the toxicity potential of melamine, cyanuric acid, and a combination of melamine and cyanuric acid in cats. In this pilot study, melamine was added to the diet of 2 cats at 0.5% and 1%, respectively. Cyanuric acid was added to the diet of 1 cat at increasing doses of 0.2%, 0.5%, and 1% over the course of 10 days. Melamine and cyanuric acid were administered together at 0%, 0.2%, 0.5%, and 1% to 1 cat per dose group. No effect on renal function was observed in cats fed with melamine or cyanuric acid alone. Cats dosed with a combination were euthanized at 48 hours after dosing because of acute renal failure. Urine and touch impressions of kidneys from all cats dosed with the combination revealed the presence of fan-shaped, birefringent crystals. Histopathologic findings were limited to the kidneys and included crystals primarily within tubules of the distal nephron, severe renal interstitial edema, and hemorrhage at the corticomedullary junction. The kidneys contained estimated melamine concentrations of 496 to 734 mg/kg wet weight and estimated cyanuric acid concentrations of 487 to 690 mg/kg wet weight. The results demonstrate that the combination of melamine and cyanuric acid is responsible for acute renal failure in cats. 相似文献
42.
Kenneth E. Joubert BVSc MMedVet Patricia A. Oglesby BVSc Justine Downie BVSc Tania Serfontein DipVetNur 《Journal of Veterinary Emergency and Critical Care》2007,17(2):184-190
Objective: To describe a case of abdominal compartment syndrome in a dog with babesiosis. Case summary: A 9‐year‐old female Bull Terrier presented with complicated babesiosis. Additional findings including respiratory distress, abdominal distension, and a decrease in urine output associated with an elevated abdominal pressure (23.5–25 cmH2O) led to a further diagnosis of abdominal compartment syndrome. This case report describes the clinical course of both conditions through resolution. New information provided: Abdominal compartment syndrome is not well described in the veterinary literature, but clinicians should be aware of this potential complication in critically ill patients. The pathophysiology and veterinary literature of abdominal compartment syndrome are reviewed. 相似文献
43.
Patricia Trotel-Aziz Michel Couderchet Guy Vernet Aziz Aziz 《European journal of plant pathology / European Foundation for Plant Pathology》2006,114(4):405-413
Chitosan (β-1,4-linked glucosamine oligomer) derived from crab shells conferred a high protection of grapevine leaves against
grey mould caused by Botrytis cinerea. Under controlled conditions, it was shown to be an efficient elicitor of some defense reactions in grapevine leaves and
to inhibit directly the in vitro development of B. cinerea. Treatment of grapevine leaves by chitosan led to marked induction of lipoxygenase (LOX), phenylalanine ammonia-lyase (PAL)
and chitinase activities, three markers of plant defense responses. Dose-response curves show that maximum defense reactions
(PAL and chitinase activities) and strong reduction of B. cinerea infection were achieved with 75–150 mg l−1 chitosan. However, greater concentrations of chitosan did not protect grapevine leaves with the same efficiency, but inhibited
mycelial growth in vitro. Present results underlined the potency of chitosan in inducing some defense responses in grapevine leaves which in turn
might improve resistance to grey mould. 相似文献
44.
R. Patricia Penilla Janet Hemingway Alma D. López 《Pesticide biochemistry and physiology》2007,89(2):111-117
The relative rates of cytochrome P450 selection in southern Mexican Anopheles albimanus populations were investigated during a 3 years indoor residual house spraying intervention with a pyrethroid (PYR) or DDT, a mosaic of organophosphate (OP)-PYR, and the annual rotation of OP-PYR-carbamate (CARB). This insecticide resistance mechanism, initially evenly spread in the mosquito population, correlated with PYR resistance during the second treated year, when cytochrome P450 contents increased in most villages of the PYR, rotation and mosaic schemes. However, by the third year, mean cytochrome P450 contents declined to susceptible levels in mosquitoes of the rotation and one mosaic group but not in the PYR-treated villages. In DDT-treated villages, a continuous decrement of cytochrome P450 levels occurred since the first treatment year, and susceptible levels were observed at the end of the intervention. Most correlations of cytochrome P450 levels and PYR resistance were lost during the third year, indicating that another mechanism evolved in resistant mosquito populations. 相似文献
45.
Cibele Soares Pontes Patricia Pereira De Lima Maria de Fátima Arruda 《Aquaculture Research》2008,39(13):1416-1422
In shrimp farms, food partitioning during the course of the day is contradictory, ethology studies may help in determining the proper frequency. Litopenaeus vannamei juveniles were placed in 30 L aquariums (41 m−2), exposed to a 12:12 h light–dark cycle. Feeding was provided at 10% of biomass three, four and seven times per day, with observations made in 15 min h−1 windows, initiated after the ration was offered. Latency to access the feeding tray and to start eating was recorded using instantaneous focal sampling and digestive tract filling (DTF) by the continuous focal method. Weight gain was recorded at the end of the experiment. We performed seven repetitions, with 28 individuals observed for 33 days for each treatment (490 h of observation). The three-times offering induced less latency for accessing the tray and for ingesting the feed as well as a higher DTF when compared with the other frequencies. Animals fed three and four times had similar weight gains, and were greater than those fed seven times. Our results indicate that a more spaced food offering stimulates the search for and ingestion of feed. As compared with other frequencies, the three-times-per-day option assumes lower labour costs and a more efficient use of the feed. 相似文献
46.
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48.
Morgane Salines Elodie Barnaud Mathieu Andraud Florent Eono Patricia Renson Olivier Bourry Nicole Pavio Nicolas Rose 《Veterinary research》2015,46(1)
In developed countries, most of hepatitis E human cases are of zoonotic origin. Swine is a major hepatitis E virus (HEV) reservoir and foodborne transmissions after pork product consumption have been described. The risk for HEV-containing pig livers at slaughter time is related to the age at infection and to the virus shedding duration. Porcine Reproductive and Respiratory Syndrome Virus (PRRSV) is a virus that impairs the immune response; it is highly prevalent in pig production areas and suspected to influence HEV infection dynamics. The impact of PRRSV on the features of HEV infections was studied through an experimental HEV/PRRSV co-infection of specific-pathogen-free (SPF) pigs. The follow-up of the co-infected animals showed that HEV shedding was delayed by a factor of 1.9 in co-infected pigs compared to HEV-only infected pigs and specific immune response was delayed by a factor of 1.6. HEV shedding was significantly increased with co-infection and dramatically extended (48.6 versus 9.7 days for HEV only). The long-term HEV shedding was significantly correlated with the delayed humoral response in co-infected pigs. Direct transmission rate was estimated to be 4.7 times higher in case of co-infection than in HEV only infected pigs (0.70 and 0.15 per day respectively). HEV infection susceptibility was increased by a factor of 3.3, showing the major impact of PRRSV infection on HEV dynamics. Finally, HEV/PRRSV co-infection – frequently observed in pig herds – may lead to chronic HEV infection which may dramatically increase the risk of pig livers containing HEV at slaughter time.
Electronic supplementary material
The online version of this article (doi:10.1186/s13567-015-0207-y) contains supplementary material, which is available to authorized users. 相似文献49.
Intravenous sufentanil‐midazolam versus sevoflurane anaesthesia in medetomidine pre‐medicated Himalayan rabbits undergoing ovariohysterectomy 下载免费PDF全文
Patricia Hedenqvist Marianne Jensen‐Waern Åsa Fahlman Ragnvi Hagman Anna Edner 《Veterinary anaesthesia and analgesia》2015,42(4):377-385
ObjectiveTo compare physiological effects of sufentanil-midazolam with sevoflurane for surgical anaesthesia in medetomidine premedicated rabbits.Study designProspective, randomized controlled experimental study.AnimalsEighteen female Himalayan rabbits, weight 2.1 ± 0.1 kg.MethodsPremedication with 0.1 mg kg−1 medetomidine and 5 mg kg−1 carprofen subcutaneously, was followed by intravenous anaesthetic induction with sufentanil (2.3 μg mL−1) and midazolam (0.45 mg mL−1). After endotracheal intubation, anaesthesia was maintained with sufentanil-midazolam (n = 9) or sevoflurane (n = 9). Ovariohysterectomy was performed. Intermittent positive pressure ventilation was performed as required. Physiological variables were studied perioperatively. Group means of physiologic data were generated for different anaesthetic periods. Data were compared for changes from sedation, and between groups by anova. Post-operatively, 0.05 mg kg−1 buprenorphine was administered once and 5 mg kg−1 carprofen once daily for 2–3 days. Rabbits were examined and weighed daily until one week after surgery.ResultsSmooth induction of anaesthesia was achieved within 5 minutes. Sufentanil and midazolam doses were 0.5 μg kg−1 and 0.1 mg kg−1, during induction and 3.9 μg kg−1 hour−1 and 0.8 mg kg−1 hour−1 during surgery, respectively. End-tidal sevoflurane concentration was 2.1% during surgery. Assisted ventilation was required in nine rabbits receiving sufentanil-midazolam and four receiving sevoflurane. There were no differences between groups in physiologic data other than arterial carbon dioxide. In rabbits receiving sevoflurane, mean arterial pressure decreased pre-surgical intervention, heart rate increased 25% during and after surgery and body weight decreased 4% post-operatively. Post-operative problems sometimes resulted from catheterization of the ear artery.ConclusionSevoflurane and sufentanil-midazolam provided surgical anaesthesia of similar quality. Arterial blood pressure was sustained during sufentanil-midazolam anaesthesia and rabbits receiving sevoflurane lost body weight following ovariohysterectomy. Mechanical ventilation was required with both anaesthetic regimens.Clinical relevanceAnaesthesia with sufentanil-midazolam in medetomidine premedicated healthy rabbits is useful in the clinical and the research setting, as an alternative to sevoflurane. 相似文献
50.
Phenolic polymer material extracted during commercial red wine fermentations (Vitis vinifera L. cv. Pinot noir) was isolated and analyzed to characterize its chemical composition. Phenolic polymer isolates were prepared from samples taken throughout fermentation and isolated by adsorption chromatography. Isolates were subjected to phloroglucinolysis to analyze the proanthocyanidin amount as well as the subunit composition. Results of phloroglucinolysis revealed that the proanthocyanidin content of individual phenolic polymer isolates varied from 27 to 54%. Subsequent analyses were done in an attempt to quantify materials other than known proanthocyanidin subunits. Results of all experiments indicate that up to 82% of the phenolic polymer isolates could be accounted for by mass. While this figure accounts for a significant portion of the polymeric phenolic material, further investigation will be needed to qualify the remaining 18%. 相似文献