44 research outputs found
Rehydration of calves : Presentation of an expert system
In addition to dehydration, diarrheic enteritis in calves is generally associated with acid-base disturbances
and fluid and electrolyte imbalances. The evaluation of these disorders, based on the measure
of blood pH and Na+, K+, C1-, HCO3- concentrations, and on the calculation of the serum anion
gap (difference between the concentrations of the major cation and the major anions) and of the
base excess, helps optimise the treatment and further refine the prognosis.
Acidosis is the most frequent disorder, with or without an increased serum anion gap depending on
the etiology of the diarrhoea. This problem is corrected by the administration of bicarbonate or carbonate
solutions. Less common disorders include alkalosis and dyskalemia.
An expert system, providing a clinical and therapeutic protocol, was developed to evaluate acid-base
and hydroelectric disorders associated with diarrheic enteritis in calves.En plus de la déshydratation,
l'entérite diarrhéique du veau est généralement associée à des déséquilibres
hydro-Ă©lectrolytiques et acido-basiques. L'Ă©valuation de ces troubles par la mesure du pH
sanguin et des concentrations sériques de Na+, K+, C1-, HCO3-, et par le calcul du
trou anionique (concentration sérique des cations diminuée de celle des anions) et de
l'excÚs de base, permet d'ajuster au mieux le traitement et de préciser le pronostic. Le
déséquilibre le plus fréquemment observé est l'acidose avec ou sans augmentation du trou
anionique selon l'étiologie de la diarrhée. L'acidose est corrigée par l'administration de
solutés bicarbonatés ou de carbonates. Les autres troubles moins fréquents sont l'alcalose
et les dyskaliémies. Un systÚme expert, sous forme d'un protocole clinique et thérapeutique,
a été développé pour évaluer les troubles acido-basiques et hydro-ioniques associés aux
entérites diarrhéiques du veau
Beyond PrPres Type 1/Type 2 Dichotomy in Creutzfeldt-Jakob Disease
Sporadic Creutzfeldt-Jakob disease (sCJD) cases are currently subclassified according to the methionine/valine polymorphism at codon 129 of the PRNP gene and the proteinase K (PK) digested abnormal prion protein (PrPres) identified on Western blotting (type 1 or type 2). These biochemically distinct PrPres types have been considered to represent potential distinct prion strains. However, since cases of CJD show co-occurrence of type 1 and type 2 PrPres in the brain, the basis of this classification system and its relationship to agent strain are under discussion. Different brain areas from 41 sCJD and 12 iatrogenic CJD (iCJD) cases were investigated, using Western blotting for PrPres and two other biochemical assays reflecting the behaviour of the disease-associated form of the prion protein (PrPSc) under variable PK digestion conditions. In 30% of cases, both type 1 and type 2 PrPres were identified. Despite this, the other two biochemical assays found that PrPSc from an individual patient demonstrated uniform biochemical properties. Moreover, in sCJD, four distinct biochemical PrPSc subgroups were identified that correlated with the current sCJD clinico-pathological classification. In iCJD, four similar biochemical clusters were observed, but these did not correlate to any particular PRNP 129 polymorphism or western blot PrPres pattern. The identification of four different PrPSc biochemical subgroups in sCJD and iCJD, irrespective of the PRNP polymorphism at codon 129 and the PrPres isoform provides an alternative biochemical definition of PrPSc diversity and new insight in the perception of Human TSE agents variability
Efficacy of sainfoin (Onobrychis viciifolia) pellets against multi resistant Haemonchus contortus and interaction with oral ivermectin: Implications for on-farm control
International audienceThe worldwide spread of resistance to anthelmintic (AH) drugs in gastrointestinal nematodes (GINS) imposes to explore alternative solutions. Amongst those, the possible use of tannin-containing nutraceuticals appears as a relevant option to replace (or decrease the frequency of) chemical-based treatments. Our objectives were to test the AH efficacy of sainfoin pellets against a multiresistant strain of Haemonchus contortus in experimentally infected lambs and to examine possible interaction between ivermectin (IVM) and condensed tannins (CT)-rich ressource. In vivo study was performed with twenty-four lambs were inoculated (Day 0) with multiresistant H. contortus infective larvae. On D21 Post-Infection, the lambs were assigned to two dietary treatments (sainfoin vs lucerne control pellets). On D39, half of the animals per group received 0.25 ml/kg of an oral ivermectin treatment. On D47, animals were slaughtered to count worms. The consumption of sainfoin was associated with higher packed cell volume (PCV) values (P < 0.05) and reduced faecal egg counts (FECs) (P < 0.05). For the experimental feeding period, FECs were overall reduced by 50% in the sainfoin group. The diet did not have significant effect on the worm number but sainfoin significantly reduced female fertility. Decrease in plasma IVM concentrations was observed in the sainfoin-fed animals and was associated with a decrease of IVM efficiency when compared with the control group. Incubating tannin in vitro with ivermectin and rumen fluid showed a blocking of ivermectin by the tannins. This suggests that tannins lower the IVM intestinal absorption compromising thereby drug plasma bioavailability and efficacy. Tannin-containing nutraceuticals alter the biology of multiresistant nematodes, thus representing an option for their sustainable control. In vivo and in vitro interactions between nutraceuticals and chemicals impose caution when both tannin -rich diet and drug-based treatments are combined. Further studies are required to clarify the mechanisms that support such interactions
Visite d'élevage lors de dégradation des résutlats sanitaires
National audienceLa dĂ©gradation des rĂ©sultats sanitaires en Ă©levage bovin est un motif frĂ©quent de visite dâĂ©levage. La dĂ©marche diagnostique repose sur une description clinique prĂ©cise et sur la dĂ©finition dâindicateurs Ă©pidĂ©miologiques pertinents. La quantification des donnĂ©es est indispensable pour situer les performances de lâĂ©levage par rapport Ă un rĂ©fĂ©rentiel. LâĂ©tablissement dâun bilan diagnostique explicatif repose sur lâinterprĂ©tation des donnĂ©es factuelles techniques et sanitaires le plus souvent informatisĂ©es, et sur lâĂ©valuation critique des animaux et des pratiques dâĂ©levage. Les mesures de maĂźtrise sont indissociables du bilan diagnostique
Maladies respiratoires enzootiques des bovins: Méthode générales d'approche
National audienceEn matiĂšre dâaffections respiratoires enzootiques des bovins, la dĂ©marche usuelle se dĂ©compose en trois temps : -une phase thĂ©rapeutique et curative immĂ©diate -une phase (rĂ©trospective) de diagnostic Ă©tiologique -une phase (prospective) de prĂ©vention et de prise en compte des facteurs de risque, pour lâannĂ©e et/ou les lots de bovins suivants. La phase thĂ©rapeutique associe anti-infectieux et anti-inflammatoires pour les animaux malades. La mĂ©taphylaxie doit ĂȘtre discutĂ©e en termes mĂ©dicaux et Ă©conomiques et en termes dâusage prudent des antibiotiques. La phase diagnostique ne peut ĂȘtre limitĂ©e aux Ă©lĂ©ments cliniques. Les donnĂ©es nĂ©cropsiques apportent plus de prĂ©cisions, et le recours au laboratoire est indispensable quand on veut Ă©tablir un diagnostic Ă©tiologique de certitude (nĂ©cessaire notamment pour les plans de prophylaxie vaccinale futurs ou la rĂ©alisation dâun antibiogrammeâŠ). La visite dâĂ©levage est le complĂ©ment prospectif indispensable. Il nâest pas possible de lâenvisager dans tous les cas, mais surtout : âą face Ă un Ă©pisode de gravitĂ© exceptionnelle âą lors de rĂ©cidive ou de rĂ©currence. La visite bĂątiment se double dâune visite plus globale sâintĂ©ressant aux flux dâanimaux (allotissements, regroupements, achatsâŠ) et aux plans dâalimentation (de la prise colostrale au sevrage et aux transitions alimentaires) et Ă la gestion de la santĂ© par lâĂ©leveur
Visite d'élevage lors de mortalité sans affection préalablement identifiée
National audienceUn taux Ă©levĂ© de mortalitĂ© conduit Ă une analyse individuelle des cas, sur le plan clinique (symptĂŽmes, caractĂ©ristiques des animaux atteints, Ă©volution clinique , durĂ©e, modalitĂ©s dâapparition et de terminaison-), nĂ©cropsique (lĂ©sions macroscopiques majeures et conclusion nĂ©cropsique) et Ă©pidĂ©miologique (rĂ©partition des cas dans le temps, lâespace, au sein de la population). Les examens nĂ©cropsiques sont indispensables dans la plupart des cas pour le diagnostic. Les retours dâexpĂ©rience sont dĂ©veloppĂ©s