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Molini Umberto Aikukutu Gottlieb Khaiseb Siegfried Kahler Barbara Van der Westhuizen Jolandie Cattoli Giovanni Dundon William G. 《Tropical animal health and production》2019,51(7):2105-2108
Between July and August 2018, two outbreaks of infectious laryngotracheitis caused the death of over 116,000 commercial poultry (layers and broilers) near the city of Windhoek, Namibia. A third outbreak occurred in September 2018 in the north of the country approximately 800 km from the original outbreaks. Sample collection and molecular epidemiological analyses revealed that the outbreaks were most likely caused by poor vaccination practices leading to the reversion to virulence of an ILT vaccine strain. The analyses also indicate that inaccurate declarations were made by one of the farms involved and that illegal movement of animals most likely occurred.
相似文献74.
Beata ebkowska‐Wieruszewska Giovanni Barsotti Francesco Camillo Alessandra Rota Duccio Panzani Amnart Poapolathep Andrzej Lisowski Mario Giorgi 《Journal of veterinary pharmacology and therapeutics》2019,42(4):440-446
Levosulpiride (LSP) is the l‐enantiomer of sulpiride, and LSP recently replacing sulpiride in several EU countries. Several studies about LSP in humans are present in the literature, but neither pharmacodynamic nor pharmacokinetic data of LSP is present for veterinary species. The aim of this study was to assess the pharmacokinetic profile of LSP after intravenous (IV), intramuscular (IM), and oral (PO) administration in goats. Animals (n = 6) were treated with 50 mg LSP by IV, IM, and PO routes according to a randomized cross‐over design (3 × 3 Latin‐square). Blood samples were collected prior and up to 24 hr after LSP administration and quantified using a validated HPLC method with fluorescence detection. IV and IM administration gave similar concentration versus time curve profiles. The IM mean bioavailability was 66.97%. After PO administration, the drug plasma concentrations were detectable only in the time range 1.5–4 hr, and the bioavailability (4.73%) was low. When the AUC was related to the administered dose in mg/kg, there was a good correlation in the IV and IM groups, but very low correlation for the PO route. In conclusion, the IM and IV administrations result in very similar plasma concentrations. Oral dosing of LSP in goats is probably not viable as its oral bioavailability was very low. 相似文献
75.
Marked lateral ventricular enlargement associated with atrophic cerebral cortex and periventricular encephalitis is described in a 2-month-old fox affected by disorientation, generalized ataxia, difficulty in walking, circling, and blindness. Clinical conditions progressed to stupor and spontaneous death within a few days. At necropsy, severe inflammatory and necrotizing lesions were observed in periventricular sites associated with diverticula and cleft formation in perithalamic areas and rhinencephalic cortex. Immunolabeling for Toxoplasma gondii, Neospora caninum, Encephalitozoon cuniculi, canine distemper virus, and rabies virus was negative. Given the presence of periventricular and choroidal neutrophilic/mononuclear cell infiltration, it is thought that a bacterial infection may have been the cause of the inflammatory lesions, with internal hydrocephalus secondary to the severe periventricular lesions. A similar condition has been previously reported in the pathogenesis of spontaneously occurring acquired canine hydrocephalus, but no viral or bacterial causes have been investigated to date. 相似文献
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OBJECTIVE: To identify and quantify ocular fungi from healthy donkeys living in the center of Italy. ANIMALS STUDIED: One hundred and two Amiata donkeys were examined. PROCEDURES: Conjunctival swabs from both eyes were seeded onto Sabouraud dextrose agar (SDA) and malt extract agar (MEA), and incubated at 25 degrees C over a 10-day period. Filamentous fungi identification was achieved to the genus level; yeast colonies were identified for macro-micromorphologic and physiological characteristics. RESULTS: Eighty-one donkeys out of 102 (79.4%) were positive for fungi; 47/102 (46.1%) had positive cultures from both eyes. Most frequently recovered fungal genera were Aspergillus spp., Penicillium spp., Cladosporium spp., Acremonium spp. Different fungal genera and/or species were recovered from the same donkey in 43 cases (42.1%). Yeasts were isolated from five subjects; the yeasts were never associated with molds. The number of colony forming units (CFU) ranged from 1 to 100. CONCLUSIONS: Aspergillus was the most commonly isolated fungal genus (33%). This result agrees with the findings of similar surveys carried out in horses. There was a remarkable presence of fungi and perfect forms. These observations may be explained by the optimal conditions for presence and development of fungi in the conjunctival fornix microenvironment in Amiata donkeys. 相似文献
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The kinetic parameters of nitrate uptake (Imax, Km and Cmin) were evaluated in young seedlings of Triticum durum L., cv. Appulo, exposed to nitrate and/or to soil‐extracted humic acids (HAs) of different molecular weight. The uptake was enhanced after induction at low levels of nitrate (50 μM KNO3), while it was inhibited after induction at higher concentrations (2000 μM). The kinetic parameters of uptake were selectively influenced by pre‐treatment with HAs: total (TE) and, at a greater extent, low (LMS, < 3500 Da) molecular size humic fraction increased either the nitrate uptake rate (Imax) and the efficiency of the whole transport system (low Km and Cmin), while an opposite result was evidenced in high molecular size (HMS, > 3500 Da)‐treated plants. An additive effect was shown when nitrate and humic substances were provided simultaneously: the uptake rate was enhanced in TE‐ and LMS‐treated plants, but was strongly delayed in HMS‐treated plants. Removal of nitrate and/or humic fractions de‐induced the system and NO3— uptake rate decreased. Exposure to HAs was not able to induce nitrate reductase activity in root and leaf tissues. Inhibitors of protein synthesis p‐fluorophenylalanine and cycloheximide reversed the positive effect of LMS fraction on nitrate uptake. This would support the hypothesis of a promoting effect of HAs on the molecular expression of proteins of the nitrate transport system. 相似文献
79.
Giovanni Romagnoni Kristina
ie Kvile Knut‐Frode Dagestad Anne Maria Eikeset Trond Kristiansen Nils Chr. Stenseth
ystein Langangen 《Fisheries Oceanography》2020,29(4):324-339
The survival of fish eggs and larvae, and therefore recruitment success, can be critically affected by transport in ocean currents. Combining a model of early‐life stage dispersal with statistical stock–recruitment models, we investigated the role of larval transport for recruitment variability across spatial scales for the population complex of North Sea cod (Gadus morhua). By using a coupled physical–biological model, we estimated the egg and larval transport over a 44‐year period. The oceanographic component of the model, capable of capturing the interannual variability of temperature and ocean current patterns, was coupled to the biological component, an individual‐based model (IBM) that simulated the cod eggs and larvae development and mortality. This study proposes a novel method to account for larval transport and success in stock–recruitment models: weighting the spawning stock biomass by retention rate and, in the case of multiple populations, their connectivity. Our method provides an estimate of the stock biomass contributing to recruitment and the effect of larval transport on recruitment variability. Our results indicate an effect, albeit small, in some populations at the local level. Including transport anomaly as an environmental covariate in traditional stock–recruitment models in turn captures recruitment variability at larger scales. Our study aims to quantify the role of larval transport for recruitment across spatial scales, and disentangle the roles of temperature and larval transport on effective connectivity between populations, thus informing about the potential impacts of climate change on the cod population structure in the North Sea. 相似文献
80.
Pierluigi Carbonara Sbastien Alfonso Francesco Gai Laura Gasco Giovanni Palmegiano Maria Teresa Spedicato Walter Zupa Giuseppe Lembo 《Aquaculture Research》2020,51(7):3007-3016
Welfare in farmed fish got particular attention during the last decades from both governmental and public sides. In aquaculture context, welfare concerns are mainly related to handling procedures, water quality and stoking densities. In Europe, authorities had to clarify the threshold limits of stocking densities to maintain fish good welfare, including for organics aquaculture through the EC regulation 710/2009. However, effects of stocking density on fish welfare are complex and sometimes contradictory. Moreover, there is a lack of knowledge about the impact of density on fish welfare in organic aquaculture. Thus, the aim of the study is to asses welfare state of rainbow trout (Oncorhynchus mykiss) at two initial stocking densities (low density, LD: 12 kg/m3 and high density, HD: 17 kg/m3) fed using organic feed by combining the monitoring of growth performances, behaviour (swimming activity) and physiological indicators (i.e. cortisol, glucose, lactate, hematocrit, red blood cellule count and lysozyme). At the end of experiment, the stocking density reached 21 kg/m3 and 30 kg/m3 for the LD and HD respectively. Overall, growth performances, swimming activity and level of physiological indicators of stress and welfare were similar between HD and LD over the experiment duration. To conclude, we observed no alteration of fish welfare between the two stocking densities monitored. This study suggests that a final stocking density of 30 kg/m3 can be considered for organic aquaculture of rainbow trout respecting welfare. 相似文献