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81.
Adverse food reaction (AFR) is a common differential diagnosis for pruritic dogs. The only way to diagnose AFR is an elimination diet of 6-8 weeks with a protein and a carbohydrate source not previously fed. In humans, patch testing has been shown to be a useful tool to diagnose food allergies. In veterinary medicine, serum food allergen-specific antibody testing is widely offered to identify suitable ingredients for such diets. The aim of this study was to determine sensitivity, specificity, negative and positive predictability of patch testing with and serum antibody testing for a variety of common food stuffs. Twenty-five allergic dogs underwent an elimination diet and individual rechallenge with selected food stuffs, food patch testing and serum testing for food-antigen specific IgE and IgG. Eleven clinically normal control dogs only were subjected to patch and serum testing. The sensitivity and specificity of the patch test were 96.7 and 89.0% respectively, negative and positive predictability were 99.3 and 63.0%. For IgE and IgG the sensitivity was 6.7 and 26.7%, specificity were 91.4 and 88.3%, the negative predictive values 80.7 and 83.7% and the positive predictive values were 15.4 and 34.8%. Based on these results, a positive reaction of a dog on these tests is not very helpful, but a negative result indicates that this antigen is tolerated well. We conclude that patch testing (and to a lesser degree serum testing) can be helpful in choosing ingredients for an elimination diet in a dog with suspected AFR. 相似文献
82.
Camargo MG Golo PS Angelo IC Perinotto WM Sá FA Quinelato S Bittencourt VR 《Veterinary parasitology》2012,188(1-2):140-147
The formulations of acaripathogenic fungi to control ticks have been widely studied. The present study evaluated the efficacy of oil-based formulations of Metarhizium anisopliae sensu lato (s.l.), isolate Ma 959, and Beauveria bassiana, isolate Bb 986, on different Rhipicephalus microplus stages, comparing the efficacy between aqueous suspensions and 10, 15 and 20% mineral oil formulations. Twelve groups were formed: one aqueous control group; three mineral oil control groups, at 10, 15 or 20%; two aqueous fungal suspensions of M. anisopliae s.l. or B. bassiana; and three formulations of M. anisopliae (s.l.) or B. bassiana containing 10, 15, and 20% mineral oil. To prepare aqueous suspensions and oily formulations, fungal isolates were cultivated on rice grains in polypropylene bags. The conidial suspensions and formulations had a concentration of 10(8)conidia/mL. Bioassays were repeated twice. After treatment, the following biological parameters of engorged females were evaluated: hatching percentage, egg production index, nutritional index, and percentage of tick control. The following parameters were evaluated in the bioassays with eggs: period of incubation, period of hatch, and hatching percentage. Mortality was evaluated in bioassays with larvae. M. anisopliae s.l. and B. bassiana oil-based formulations were more effective than aqueous suspensions against R. microplus eggs, larvae and engorged females, however, there was no significant difference between the three oil concentrations used. M. anisopliae s.l. and B. bassiana formulated in mineral oil reached 93.69% and 21.67% efficacy, respectively, while M. anisopliae s.l. and B. bassiana aqueous suspensions attained 18.70% and 1.72% efficacy, respectively. M. anisopliae s.l. oil-based formulations caused significant effects in all biological parameters of engorged females while B. bassiana oil-based formulations modified significantly the nutritional index only. Eggs treated with M. anisopliae s.l. and B. bassiana oil-based formulations showed hatching rates that decreased 102.5 and 3.65 times, respectively. In the bioassay with larvae, M. anisopliae s.l. oil-based formulations caused nearly 100% mortality five days after treatment, while larva treated with B. bassiana oil-based formulations reached 100% mortality at day 20 after treatment. Larva from oil-based control groups showed mortality at day 15 after treatment, which indicated a possible toxic effect of the oil for this R. microplus stage. The results showed that the fungal mineral oil formulations tested were more effective than the aqueous suspension. Oil-based formulations at 10, 15 and 20% enhanced the activity of M. anisopliae s.l. Ma 959, and B. bassiana Bb 986, isolates against R. microplus eggs, larvae, and engorged females tick. Mineral oil was effective as an adjuvant in formulations of M. anisopliae s.l., Ma 959, and B. bassiana, Bb 986, for the control of R. microplus under laboratory conditions. 相似文献
83.
In the literature, studies of Chlamydia infection in birds have usually been confined to the search for Chlamydia (C., formerly Chlamydophila) psittaci, so that little is known about the presence of other chlamydial agents. In the present study, cloacal swabs and faeces samples of urban pigeons have been examined by real-time PCR, DNA microarray assays and partial ompA sequencing. Whilst C. psittaci was the predominant chlamydial agent in this pigeon population (75.8% of all Chlamydiaceae positives), the combined use of highly specific and sensitive molecular assays facilitated the detection of atypical serovars of C. psittaci, as well as other species of Chlamydia, such as C. abortus. Detection of C. pecorum and C. trachomatis from an avian host is reported here for the first time. Rather unexpectedly, 19.5% of all Chlamydiaceae-positive cases turned out to be infected with non-classified organisms. The considerable prevalence of these novel agents raises the question of their epidemiological importance and possible role as pathogens. Future surveys in domestic and wild birds will have to take the extended variety of chlamydial organisms into account. 相似文献
84.
Ringer SK Portier KG Fourel I Bettschart-Wolfensberger R 《Veterinary anaesthesia and analgesia》2012,39(1):12-20
ObjectiveTo determine constant rate infusion (CRI) protocols for romifidine (R) and romifidine combined with butorphanol (RB) resulting in constant sedation and romifidine plasma concentrations.Study designBlinded randomized crossover study.AnimalsTen adult research horses.MethodsPart I: After determining normal height of head above ground (HHAG = 100%), loading doses of romifidine (80 μg kg?1) with butorphanol (RB: 18 μg kg?1) or saline (R) were given intravenously (IV). Immediately afterwards, a butorphanol (RB: 25 μg kg?1 hour?1) or saline (R) CRI was administered for 2 hours. The HHAG was used as marker of sedation depth. Sedation was maintained for 2 hours by additional romifidine (20 μg kg?1) whenever HHAG > 50%. The dose rate of romifidine (μg kg?1 hour?1) required to maintain sedation was calculated for both treatments. Part II: After loading doses, the romifidine CRIs derived from part I were administered in parallel to butorphanol (RB) or saline (R). Sedation and ataxia were evaluated periodically. Romifidine plasma concentrations were measured by HPLC-MS-MS at 0, 5, 10, 15, 30, 45, 60, 90, 105, and 120 minutes. Data were analyzed using paired t-test, Fisher's exact test, Wilcoxon signed rank test, and two-way anova for repeated measures (p < 0.05).ResultsThere was no significant difference in romifidine requirements (R: 30; RB: 29 μg kg?1 hour?1). CRI protocols leading to constant sedation were developed. Time to first additional romifidine bolus was significantly longer in RB (mean ± SD, R: 38.5 ± 13.6; RB: 50.5 ± 11.7 minutes). Constant plasma concentrations of romifidine were achieved during the second hour of CRI. Ataxia was greater when butorphanol was added.ConclusionRomifidine bolus, followed by CRI, provided constant sedation assessed by HHAG. Butorphanol was ineffective in reducing romifidine requirements in unstimulated horses, but prolonged the sedation caused by the initial romifidine bolus.Clinical relevanceBoth protocols need to be tested under clinical conditions. 相似文献
85.
Antonio De Simone Floriana Gernone Mario Ricciardi 《Veterinary radiology & ultrasound》2013,54(2):159-163
An 8‐month‐old intact male English Setter was presented with bilateral shoulder lameness. Radiographic and CT examinations demonstrated bilateral irregular margination and separation of the supraglenoid tubercle from the scapula, with involvement of the cranial articular surface of the glenoid cavity. After 30 days of cage rest, complete fusion of proximal portions of both supraglenoid tubercles and persistent un‐united cranial portions of both glenoid cavities were evident. Histopathologic findings from biopsies of glenoid cavity defects were consistent with osteochondrosis or focal chondrodysplasia. 相似文献
86.
Simone M. Cacciò Anna Rosa Sannella Valeria Mariano Silvia Valentini Franco Berti Fabio Tosini Edoardo Pozio 《Veterinary parasitology》2013,191(1-2):128-131
An outbreak of cryptosporidiosis occurred in a mixed sheep/cattle farm of Central Italy in October 2011. A total of 450 ovines (250 sheep and 200 lambs) and 140 bovines (130 cows and 10 calves) were housed in two separated units, at the time of the outbreak. About half of the lambs had diarrhea due to Cryptosporidium sp. with a mortality rate of 80%; calves were not infected. Genomic DNA was extracted from an archived slide and from fecal specimens, and the parasite was identified as Cryptosporidium parvum by PCR and sequence analysis at the CpA135 gene. Genotyping at the GP60 gene showed the presence of a very rare genotype, IIaA20G2R1. Shortly after the outbreak was identified, the son of the farm's owner, aged 18 months, experienced an acute gastroenteritis and was hospitalized due to recurrent episodes of diarrhea, fever, vomiting and lack of appetite. The feces tested negative for bacteria and viruses, whereas cryptosporidiosis was diagnosed by microscopy and an immunochromatographic test. Molecular typing identified the C. parvum genotype IIaA20G2R1 in the feces of the child. This is the first case of transmission of cryptosporidiosis in Italy involving lambs as source of oocysts infectious to humans. 相似文献
87.
Tatiana da Rosa Guimar?es Carlos Guillermo Quiroz Caroline Rigotto Simone Quintana de Oliveira Maria Tereza Rojo de Almeida éverson Miguel Bianco Maria Izabel Goulart Moritz Jo?o Luís Carraro Jorge Alejandro Palermo Gabriela Cabrera Eloir Paulo Schenkel Flávio Henrique Reginatto Cláudia Maria Oliveira Sim?es 《Marine drugs》2013,11(11):4176-4192
The n-butanol fraction (BF) obtained from the crude extract of the marine sponge Petromica citrina, the halistanol-enriched fraction (TSH fraction), and the isolated compounds halistanol sulfate (1) and halistanol sulfate C (2), were evaluated for their inhibitory effects on the replication of the Herpes Simplex Virus type 1 (HSV-1, KOS strain) by the viral plaque number reduction assay. The TSH fraction was the most effective against HSV-1 replication (SI = 15.33), whereas compounds 1 (SI = 2.46) and 2 (SI = 1.95) were less active. The most active fraction and these compounds were also assayed to determine the viral multiplication step(s) upon which they act as well as their potential synergistic effects. The anti-HSV-1 activity detected was mediated by the inhibition of virus attachment and by the penetration into Vero cells, the virucidal effect on virus particles, and by the impairment in levels of ICP27 and gD proteins of HSV-1. In summary, these results suggest that the anti-HSV-1 activity of TSH fraction detected is possibly related to the synergic effects of compounds 1 and 2. 相似文献
88.
Simone Vincenzi Alain J. Crivelli Jean-Francois Rubin Giulio A. De leo 《Biological conservation》2008,141(1):198-210
While several population viability analyses (PVAs) have been performed on anadromous salmonids, less attention has been given to stream-living salmonids. In this work, we explore the role of PVA as a tool in the recovery of threatened stream-living salmonid species. The analysis has been performed with reference to marble trout Salmo marmoratus, a salmonid with a limited geographic distribution and at risk of extinction due to hybridization with the non-native introduced brown trout. Demographic parameters, such as survival, fecundity and density-dependent patterns were estimated from an eight year on-going monitoring program of two translocated marble trout populations in pristine, previously fishless streams (Zakojska and Gorska) in the Soca and Idrijca river basins (Slovenia). To explore the importance of disturbance events such as floods on marble trout population dynamics, we performed a PVA under three scenarios: (1) occurrence of both severe and moderate floods; (2) occurrence of only moderate floods; (3) no flood events. Our analysis shows that population viability is threatened only by severe flood events, otherwise the two populations prove to be fairly stable with population abundance fluctuating around stream carrying capacity. A sensitivity analysis performed on model parameters highlighted that density-dependence in first-year survival and the magnitude of reduction in population size after a severe flood are the two most crucial parameters affecting population abundance and quasi-extinction probability, respectively. While only extreme floods can drive the population to extinction, the increase in juvenile survival when population abundance collapses after a major flood may allow the populations to quickly recover from few reproductive individuals back to stream carrying capacity. 相似文献
89.
Species with strong preferences for early or late successional stages after fire may be extinction prone under current fire regimes. However, the extent of specialisation to time since fire is poorly understood, and, for reptiles, succession models for predicting responses are in the development phase. In this study we tested predictions of a reptile succession model, and identified species that may be fire specialists. Reptiles were sampled in five burnt and unburnt mallee Eucalyptus woodlands, Australia. Two, 400 m transects within each burn treatment were sampled using 11 pairs of pitfall-traps that were opened for five weeks over two summers. A habitat accommodation model of succession that was previously developed for mallee reptiles correctly predicted the observed responses of three of 16 common reptile species. A further four species showed non-significant trends in the predicted direction. However, eight other species showed unexpected responses. One species showed a strong interaction between burn age and location, requiring a two-dimensional successional model in contrast with the usual linear models explaining reptile responses to fire. One third of common species were not affected by fire and so may not have increased risks of extinction due to the fire suppression/incineration cycle. However, approximately half to two-thirds of common reptiles did have a fire response, so the risk of deterministic extinction in small fragments may be substantial. Further model development is needed to better predict fire responses and to assist the design of fire mosaics that can accommodate early and late successional fire specialists. 相似文献
90.
Application of a sensomics approach on the water-soluble extract of a matured Gouda cheese including gel permeation chromatography, ultrafiltration, solid phase extraction, preparative RP-HPLC, and HILIC combined with analytical sensory tools enabled the comprehensive mapping of bitter-tasting metabolites. LC-MS-TOF and LC-MS/MS, independent synthesis, and sensory analysis revealed the identification of a total of 16 bitter peptides formed by proteolysis of caseins. Eleven previously unreported bitter peptides were aligned to beta-casein, among which 6 peptides were released from the sequence beta-CN(57-69) of the N terminus of beta-casein and 2 peptides originated from the C-terminal sequence beta-CN(198-206). The other peptides were liberated from miscellaneous regions of beta-casein, namely, beta-CN(22-28), beta-CN(74-86), beta-CN(74-77), and beta-CN(135-138), respectively. Six peptides were found to originate from alpha(s1)-casein and were shown to have the sequences alpha(s1)-CN(11-14), alpha(s1)-CN(56-60), alpha(s1)-CN(70/71-74), alpha(s1)-CN(110/111-114), and alpha(s1)-CN(135-136). Sensory evaluation of the purified, synthesized peptides revealed that 12 of these peptides showed pronounced bitter taste with recognition thresholds between 0.05 and 6.0 mmol/L. Among these peptides, the decapeptide YPFPGPIHNS exhibited a caffeine-like bitter taste quality at the lowest threshold concentration of 0.05 mmol/L. 相似文献