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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83.
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
84.
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
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1H‐NMR metabolomic profiling of the crayfish Astacus leptodactylus subjected to polyphenol‐enriched diets 下载免费PDF全文
Susan Costantini Lucia Parrillo Eliana Guerriero Dominique Melck Giovanni Colonna Maria Grazia Volpe Marina Paolucci 《Aquaculture Nutrition》2018,24(1):524-538
1H‐NMR analysis of the hepatopancreas, muscle and haemolymph of Astacus leptodactylus after feeding with polyphenol‐enriched diet is reported. 1H‐NMR spectra of lipophilic extracts showed the presence of cholesterol, fatty acid residues, phospholipids and triglycerides. 1H‐NMR spectra of aqueous extracts identified 35 metabolites in the hepatopancreas, 31 in the muscle and 22 in the haemolymph. A total of 20 metabolites (amino acids and their derivatives) were present in the hepatopancreas, the muscle and the haemolymph. A total of 10 metabolites were present in both the hepatopancreas and the muscle (five amino acids, 2‐hydroxybutyrate, choline, myo‐inositol, glycogen and uracil). 2‐Hydroxyisobutyrate and creatine were present in both the hepatopancreas and the haemolymph. Phosphorylethanolamine, phosphocholine and fumarate were present only in the hepatopancreas and isoleucine only in the muscle. Statistical analysis showed that the percentage of weight gain was statistically higher in polyphenol‐enriched diet groups compared to the control and that polyphenols had a stimulating effect on the general metabolism. No stress‐related metabolites were higher in crayfish fed with polyphenol‐enriched diet. Conversely, phosphatidylcholine, cholesterol and DHA, linked to resistance to environmental stress and diseases, were higher compared to the control diet. This study indicates that 1H‐NMR is a useful tool to study the metabolomics in relation to diet differences. 相似文献
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Should I fight or should I flight? How studying insect aggression can help integrated pest management 下载免费PDF全文
Giovanni Benelli 《Pest management science》2015,71(7):885-892
Aggression plays a key role all across the animal kingdom, as it allows the acquisition and/or defence of limited resources (food, mates and territories) in a huge number of species. A large part of our knowledge on aggressive behaviour has been developed on insects of economic importance. How can this knowledge be exploited to enhance integrated pest management? Here, I highlight how knowledge on intraspecific aggression can help IPM both in terms of insect pests (with a focus on the enhancement of the sterile insect technique) and in terms of biological control agents (with a focus on mass‐rearing optimisation). Then, I examine what implications for IPM can be outlined from knowledge about interspecific aggressive behaviour. Besides predator–pest aggressive interactions predicted by classic biological control, I focus on what IPM can learn from (i) interspecific aggression among pest species (with special reference to competitive displacement), (ii) defensive behaviour exhibited by prey against predaceous insects and (iii) conflicts among predaceous arthropods sharing the same trophic niche (with special reference to learning/sensitisation practices and artificial manipulation of chemically mediated interactions). © 2015 Society of Chemical Industry 相似文献
90.
Elisa Brunelli Giulia Pinton Paolo Bellini Alberto Minassi Giovanni Appendino Laura Moro 《Fitoterapia》2009,80(6):327-332
The activity of 8-prenylapigenin (8-PA) and its 3'-methoxylated analogue isocannflavin B (IsoB) was investigated in estrogen-dependent T47-D and estrogen-independent MDA-MB-231 human breast cancer cell lines. 8-PA showed a biphasic effect on T47-D cell proliferation, while no significant effect was observed on MDA-MB-231 cells. Conversely, IsoB exhibited only an inhibitory effect on T47-D cell proliferation, accompanied by the appearance of an intense intracytoplasmic vacuolization of autophagic origin. Moreover, biochemical analysis showed that IsoB reduced Akt phosphorylation and p21Cip1 expression in T47-D cells. These data show that the prenylflavone moiety is a versatile platform for the induction and modulation of bioactivity. 相似文献