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321.
Epizootic rabbit enteropathy (ERE) emerged and spread in Europe within the last 13 years causing major economical loss. The
aims of the study was to evaluate antibiograms of TEC4, an inoculum composed of an extract of intestinal content of affected
rabbits, and to test the potential of different antibiotic-based TEC4 fractions to reproduce the disease. Twenty nine different
antibiotic discs were incubated for determining bacteria resistance. In a complementary study, nine tubes of liquid medium
were inoculated with TEC4, incubated and added individually with amoxicillin/clavulanic acid, bacitracin, ceftiofur, doxycycline,
novobiocin, streptomycyin, tylosin, vancomycin and 0.9% saline solution as control. The content of each tube was washed by
centrifugation and suspended in saline. The three most effective antibiotics are florfenicol, amoxycillin/clavulanic acid
and tylosin. A high concentration of Clostridium sordelli and Bacillus firmus were isolated in all fractions. Species never cultured from TEC4 were identified as Fusobacterium necrogenes (in vancomycin fraction), Cellulomonas sp (in novobiocin fraction) and Bacteroides distasonis (in doxycycline fraction). The ERE was reproduced when bacitracin, doxycycline and 0.9% fractions were inoculated. Rabbits
showed ERE clinical signs with the specific drop in daily weight gain. 相似文献
322.
Popa I Pin D Remoué N Remoué N Osta B Callejon S Videmont E Gatto H Portoukalian J Haftek M 《Veterinary research communications》2011,35(8):501-509
Alterations of the lipid expression in the skin of human and canine atopic subjects may be one of the key factors in the disease
development. We have analyzed the ultrastructure of the clinically uninvolved skin of atopic dogs and compared it with the
lipid composition of their tape-stripped stratum corneum (SC). The effect of a 2 month treatment of atopic dogs by food supplementation
with a mixture of essential fatty acids was evaluated on skin samples taken before and after the treatment period. Electron
microscopy revealed that the non-lesional skin of atopic dogs exhibited an abnormal and largely incomplete structure of the
lamellar lipids with little cohesion between the corneocyte strata. The SC of atopic dogs was characterized by a significant
decrease in the lipid content when compared to the healthy controls. Following oral supplementation with the mixture of essential
fatty acids, the overall lipid content of the SC markedly increased. This feature was observed both with the free and, most
importantly, with the protein-bound lipids (cholesterol, fatty acids and ceramides), the latter constituting the corneocyte-bound
scaffold for ordinate organisation of the extracellular lipid bi-layers. Indeed, the semi-quantitative electron microscopy
study revealed that the treatment resulted in a significantly improved organization of the lamellar lipids in the lower SC,
comparable to that of the healthy dogs. Our results indicate the potential interest of long-term alimentary supplementation
with omega-6 and omega-3 essential fatty acids in canine atopic dermatitis. 相似文献
323.
Understanding the determinants of hedgerow plant diversity in agricultural landscapes remains a difficult task, because the
potential drivers affect the complete range of biodiversity components (alpha to gamma diversity). We surveyed herbaceous
plant communities (of a height <1.5 m) in 84 hedgerows in the Seine river floodplain of France. Two types of potential drivers
for species richness, accounting for landscape mosaic and hedgerow network, were recorded at both hedgerow and site scale.
The distribution of species richness through the components of alpha hedgerow diversity (i.e. the average diversity within
a habitat) and gamma hedgerow diversity (i.e. the total diversity across habitats) were assessed using additive partitioning
methods, while the relationship between species diversity and its potential landscape drivers at both scales was modeled using
Generalized Additive Models. Our results indicated that gamma hedgerow diversity is explained by the heterogeneity of the
landscape structure, which is correlated with the mosaic of agricultural land use. At this scale, intrinsic properties of
the configuration of the hedgerow networks have a weak influence on species richness. Alpha hedgerow diversity is also explained
by landscape variables, accounting for both the configuration of agricultural mosaics and hedgerow networks, but to a lesser
extent. Time lags for species responses are shown at both scales, and for the two types of drivers. Extinction or colonization
debt may be indicated at both scales, while the remnant effects of former practices may also be responsible for such patterns
at a local scale. We suggest that hedgerow management should take the specific parameters of both scales into account. At
a local scale, management actions should aim to decrease the influence of adjacent land use when the impact is negative, through
the implementation of extended buffer zones, while at the landscape and farm scales, agri-environmental schemes should be
dedicated to the conservation of specific agricultural land uses. 相似文献
324.
Palierne S Mathon D Asimus E Concordet D Meynaud-Collard P Autefage A 《Research in veterinary science》2008,85(3):407-417
ObjectiveThe incidence of femoral traumatology and hip dysplasia shows the need to design canine specific femoral implants in veterinary surgery. A good knowledge of femoral morphology, and particularly of intra-species variability, is required to develop a well-adapted canine femoral intramedullary implant. The aim of this study is to evaluate the morphological variability of the canine femur and to propose a segmentation of this population.ProcedureThis study proposes different possibilities for the segmentation of a canine population of 103 dogs of various common breeds in relation to their femoral morphology. These segmentations were obtained with a statistical methodology, which takes into account 24 measured and calculated morphological parameters of 206 canine femurs.ResultsThe segmentation of this canine population into four or six homogeneous groups related to the femoral morphology were the two most relevant solutions. The total length of the femur and the femoral head diameter were the best discriminant parameters for this segmentation.ConclusionKnowledge of the variability of the femoral morphology in the canine species and the possibility of splitting the canine population into homogeneous morphological groups are useful for the design of specific canine femoral implants. The femoral morphological profiles of each group constitute an essential database for fitting the best orthopedic implant to the bone. 相似文献
325.
Alain Regnier Iris Berton Didier Concordet Jean-Yves Douet 《Veterinary anaesthesia and analgesia》2018,45(2):158-164
Objective
To assess the degree and duration of corneal anaesthesia provided by topical application of a non-ophthalmic 2% lidocaine gel in horses.Study design
Experimental, ‘blinded’, randomized prospective study.Animals
Twelve adult horses without relevant ocular abnormalities.Methods
Baseline corneal touch threshold (CTT) measurements were obtained bilaterally by use of a Cochet–Bonnet aesthesiometer just prior to topical treatment. A volume of 0.2 mL of 2% lidocaine gel was administered in one randomly selected eye and the same volume of a viscous lubricant in the other eye to serve as control. The CTT value was measured on both eyes 5, 10, 20, 30, 45, 60, 75 and 90 minutes after drug application. The potential for local adverse effects following lidocaine gel application was also evaluated.Results
Mean CTT baseline measurements were not significantly different (p > 0.05) between the control eyes (3.41 ± 0.56 cm) and those subsequently treated with the lidocaine gel (3.50 ± 0.64 cm). In control eyes, no significant changes in corneal sensitivity (p > 0.05) occurred over time during the study period. By contrast, a marked reduction in corneal sensitivity was observed after lidocaine application, with mean CTT values significantly lower (p < 0.001) than those of the control eyes from 5 to 75 minutes. A steady-state maximal corneal anaesthesia was present from 10 to 45 minutes after lidocaine gel application with mean CTT values ranging from 0.21 to 0.45 cm. Corneal epithelial irregularities were detected in three lidocaine-treated eyes, but spontaneous resolution occurred within 24 hours.Conclusions and clinical relevance
Deep and sustained corneal anaesthesia is achieved after application of 2% lidocaine gel to the equine eye, with minimal changes in the corneal epithelium. It might be useful for minor ophthalmic surgeries performed in the standing sedated horse. 相似文献326.
Hélène Deflers Frédéric Gandar Géraldine Bolen Frédéric Farnir Didier Marlier 《Veterinary anaesthesia and analgesia》2018,45(4):510-519
Objective
To establish a noninvasive imaging protocol for rabbit gastrointestinal transit evaluation. To assess the effect of a single injection of buprenorphine on the digestive transit of rabbits via this new technique.Study design
Prospective, parallel study.Animals
Fifteen specific pathogen-free male New Zealand White rabbits weighing 2.68 ± 0.28 kg.Methods
A 10 mL kg–1 barium meal was administered and the rabbits were subjected to serial radiographic and ultrasound examinations without treatment and 1 week later following a single intramuscular dose of 100 μg kg–1 of buprenorphine. Radiographic data from the stomach and caecum were collected and assigned a retention score ranging from 0 (no barium) to 3 (large amount of barium). The resulting scores and pyloric and duodenal contraction counts were analysed using a mixed linear model and are expressed as least square mean (lsm) ± standard error. Transit was estimated based on the apparition time of faeces in the pelvic area and analysed using a Wilcoxon test. A p < 0.05 was considered significant.Results
Buprenorphine treatment induced a higher lsm number of pyloric (1.73 ± 0.19 versus 0.78 ± 0.19, p < 0.01) and lsm duodenal contractions (17.35 ± 1.04 versus 13.44 ± 1.04, p < 0.01). Buprenorphine administration decreased the lsm barium retention score in the stomach (2.44 ± 0.05 versus 2.64 ± 0.05, p < 0.01), but had no effect on the lsm barium retention score in the caecum. The time to apparition of faeces in the pelvic area was not influenced by buprenorphine administration (p = 0.66).Conclusions and clinical relevance
A single high dose of buprenorphine appears to have no adverse effect on gastrointestinal motility in healthy rabbits. 相似文献327.
Paulo Salgado Vu Q. Thang Tran V. Thu Nguyen X. Trach Vu C. Cuong Philippe Lecomte Didier Richard 《Tropical animal health and production》2013,45(2):561-568
In North Vietnam, during winter, alternative forage resources are needed to balance the feed ration of dairy cows. The objective of this study was to investigate the effect of oat forage as a component of traditional winter roughage diets on feed intake, milk production and feeding cost in dairy cows. The study was conducted on-farm using 24 mid-lactation Holstein–Friesian cows. The feeding experiment consisted of two successive periods and two dietary treatments per period. Traditional basal diets included fresh tropical grasses, maize silage and hay. The oat forage had no effect on the dry matter intake of the basal diet, but the total crude protein intake was higher in cows fed with oat diets than in those fed with control diets. The yield of butterfat-corrected milk (FCM) was not significantly different between diets during period 1, but there was a trend (P?=?0.078) of higher FCM yields in cows fed with the oat diet compared to those with control diet during period 2 (17.3 vs. 16.3 kg/day). The decline rate in milk yield was significantly higher (P?<?0.001) in cows fed with control diets than in those fed with oat diets in both experimental periods. The total feeding cost of cows fed with oat diets was on average 12 % lower than those fed with control diets (P?<?0.01). So, the oat forage is an important winter resource for cows in North Vietnam allowing higher milk yield whilst reducing feeding cost, compared to traditional roughage diets. 相似文献
328.
I. Caudron S. Grulke F. Farnir P. Vanschepdael D. Serteyn 《The Veterinary quarterly》2013,33(4):131-135
Summary Adaptation of an in‐foot shoe force sensor and the gait analysis system ‘Fscan’ makes it possible to monitor the distribution of the vertical forces under the equine foot in motion. The aim of this study is to investigate the effects of two different trimmings on forces under the foot during the trot. The first one increased the height of the lateral hoof wall and the second one restored the mediolateral balance of the foot. These two trimmings were examined by using a radiographical method that quantifies the interphalangeal articular asymmetries due to asymmetrical bearing. The location of the centre of force of the weight‐bearing foot and the distribution of the forces applied to the lateral and medial solar surfaces during a stride were analyzed. After optimal trimming, the centre of force of the weight‐bearing foot tended to approach the centre of the palmar figure, perpendicular to the distal interphalangeal joint centre. The sum of the forces recorded under the lateral and medial parts respectively of the foot during one stride tended to balance out after corrective trimming. 相似文献
329.
Amadou?Sarr Boubacar?Diop Regis?Peltier Marc?Neyra Didier?LesueurEmail author 《New Forests》2005,29(1):75-87
The purpose of this work was to determine the most efficient methods of inoculation to significantly improve nodulation and growth of Acacia senegal and Acacia nilotica, grown under greenhouse conditions. Our results showed that inoculation using dissolved alginate beads containing rhizobia significantly improved the growth of both acacia species better than the growth of plants in other treatments. The experiment with A. nilotica was conducted in two unsterilised soils from different areas. Plants grown in soil from Bel Air were well-nodulated and showed better growth than plants grown in soil from Sangalkam. However, no difference between these soils was shown between the several methods of inoculation and their effect on the nodulation and growth of plants. An interaction between A. senegal and A. nilotica provenances and the effect of inoculation with rhizobia was also demonstrated. Bel Air provenance of A. senegal, Dahra and RIM provenances of A. nilotica grew best of several provenances tested. These results suggest that (1) it may be possible to improve growth and yield of A. senegal and A. nilotica by careful selection of each symbiotic partner; and (2) nursery-grown seedlings of A. senegal and A. nilotica should be inoculated, just after sowing, with dissolved alginate beads containing a mixture of selected rhizobia.
Résumé.
Lobject de notre travail était de déterminer la méthodologie dinoculation la plus efficace pour améliorer significativement la nodulation et la croissance dAcacia senegal et dAcacia nilotica poussant dans des conditions de serre. Nos résultats ont montré que linoculation utilisant des billes dalginate dissoutes améliorait significativement la croissance des deux espèces dAcacia par rapport à celle des plantes des autres traitements. Lexpérience avec A. nilotica a été faite dans deux types de sol non stériles. Nous avons observé que les plants poussant dans le sol de Bel Air étaient plus nodulés et mieux développés que ceux poussant dans le sol de Sangalkam. Cependant, aucune différence significative entre les deux sols na été mise en évidence en termes deffet des différentes méthodologies dinoculation sur la nodulation et la croissance des plantes. Il a aussi été démontré lexistence dune interaction entre les provenances dA. senegal et dA. nilotica et leffet de linoculation avec rhizobium. Cest ainsi que les provenances Bel Air dA. senegal, Dahra et RIM dA. nilotica ont le mieux poussé parmi les différentes provenances testées. Lensemble de ces résultats suggèrent: (1) il devrait être possible daméliorer la croissance et la production dA. senegal et dA. nilotica par une sélection des deux partenaires symbiotiques; (2) Les jeunes plantules dA. senegal et dA. nilotica produites en pépinière devraient être inoculées juste après le semis avec des billes dalginate dissoutes contenant un cocktail de souches sélectionnées. 相似文献
330.
Dries Vansteenkiste Joris Van Acker Marc Stevens Didier Le Thiec Gérard Nepveu 《Annals of Forest Science》2007,64(1):11-19
SEM and light-microscopical observations, supported by chemical microanalysis with an EDXA system, revealed that light-saturated pixels observed in X-ray negatives of sessile oak (Quercus petraea Liebl.) wood were caused by inorganic deposits present inside multiseriate ray and axial parenchyma cells. Calcium oxalate crystals, silica grains and amorphous granules with varied mineral compositions have been identified. The wood strips of three out of six sampled trees contained measurable amounts of mineral inclusions which were quantified using image analysis. Based on the variations of mineral content observed between trees and within and between annual rings of the same tree, some hypotheses were formulated concerning the factors involved in the formation of inorganic deposits in oak wood. Their occurrence varies depending on the mineral concerned and seems to be controlled largely by a tree effect. The time of formation appears to coincide with a shifting of the oak wood’s functions as a result of heartwood formation processes (inter-annual scale) or changes in leaf phenology and climate (intra-annual scale). In addition, the technical consequences of their presence as well as their effects on wood density measurements through microdensitometry are discussed. 相似文献