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Bulk tank milk (BTM) is an easy, inexpensive, and representative sample for detection of Coxiella burnetii infections (Q fever) in dairy herds using real-time PCR. Bulk tank milk PCR can be performed either for initial herd screening or for monitoring the effectiveness of preventive measures. However, one major limitation under field conditions is the need to deliver BTM samples in adequate condition (quickly, safely, and under refrigeration) to a qualified laboratory. In addition, sending non-inactivated biological samples via normal mail may be prohibited. We developed an innovative, easy, and accurate diagnostic tool (QTest) for Q fever to support veterinarians and farmers in overcoming these constraints. The farmer or veterinarian simply places some drops of BTM on a Whatman FTA Elute Micro Card (FTA card) and lets the card dry before mailing it to the laboratory. In a 2-step study, we tested the hypotheses that (1) BTM samples stored on FTA cards are stable over time and at different temperatures, and (2) PCR results obtained via FTA cards are consistent with those obtained from raw BTM samples. The stability of C. burnetii DNA in milk preserved on an FTA card was maintained for at least 29 d at room temperature or 37°C to mimic field conditions. In our field study, of the original 70 positive BTM samples (when tested on raw BTM just after sampling), 58 samples were positive (on either raw BTM or FTA card) by the time of the direct comparison study (10 to 14 d later). Of these 58 samples, 45 raw BTM samples still tested positive after aging, and 53 FTA card BTM samples tested positive, indicating that detection was higher using FTA cards (91.4%) than raw milk (77.6%). Therefore, with inactivation and shipping advantages, this technique facilitates an easier and more practical approach to diagnosis of Q fever at the herd level and would support Q fever control strategies, especially in countries lacking adequate and close laboratory facilities.

Les ruminants sont des animaux sensibles, doués de capacités émotionnelles et cognitives, pouvant être soumis à différents types de douleur (excès de nociception ou neuropathique) et ceci dans différents contextes (élevage/expérimentation). L’évaluation de ces douleurs est bien souvent délicate car, pour la plupart des cas, il n’existe pas d'indicateur unique et spécifique mais plutôt un ensemble d'indicateurs dont les valeurs informatives sont souvent complémentaires. Une évaluation adéquate de la douleur est essentielle afin d'optimiser sa prise en charge et utiliser au mieux l'arsenal thérapeutique actuellement à la disposition des prescripteurs. En effet, les molécules ayant des mécanismes d’action différents, il est nécessaire de pouvoir quantifier l’intensité douloureuse et évaluer le type de douleur mis en cause. A travers cette synthèse, nous montrerons en quoi : i) l’évaluation du type et du niveau de douleur est indispensable à une prise en charge optimale de la douleur, ii) qu’une évaluation reposant sur une approche multiparamétrique est la plus adaptée à notre objectif., Ruminants are sentient beings, endowed with emotional and cognitive abilities, which can perceive different types of pain (nociceptive or neuropathic) in different types of contexts (breeding / experimentation). Assessing pain is often difficult because, in most situations of pain, there is not a unique and specific indicator but rather a set of complementary indicators. An accurate assessment of pain is essential to optimize care and use of the therapeutic arsenal currently available to prescribers. Indeed, the therapeutic arsenal with different mechanisms of action, it is necessary to quantify pain intensity and the type of pain assessment. Through this review, we will show how: i) accurate assessment is essential for optimal management of pain, ii) method of assessment depends on the type of pain that is suspected and can be based on a multiparametric approach, a limited number, or even a single indicator as appropriate.

The objective of this study was to evaluate the effect of the implementation of different footbathing practices using a new biocide solution (Pink-Step™, Qalian, France) in the healing and the occurrence of bovine digital dermatitis (bDD) lesions. The investigation was conducted through a controlled within cow clinical trial in which the hind feet of cows from each farm were allocated either to the control group or to a moderate (MR) or (IR) intensive footbath-regimen groups. The trial involved 1036 cows (2072 feet) from 10 dairy farms located in western France where bDD was endemic. Split-footbaths were placed at the exit of the milking parlor of each farm, allowing the biocide to be administered to one side of the cows while using the other empty side as a negative control. The administration frequency for MR was of 2 days/week/1st-month, then 2 days/2 weeks/2nd-month, and then 2 days/month, and for IR was of 2 days/week/1st-2nd months, and then 2 days/2 weeks. Footbaths were administered during 140 days (approx.), and feet were evaluated for the at least once a month in the milking parlor. Nested survival models were used to estimate the relative impact of the footbath regimens and other concomitant risk factors on the time that bDD lesions occurred or healed. No effect of Pink-Step™ was evidenced on the bDD occurrence during the trial. The risk for bDD occurrence was increased by poor feet cleanliness at both the cow (HR 1.69, CI 1.21–2.39) and farm level (HR 2.06, CI 1.44–2.94). Otherwise, the use of Pink-Step™ in an IR was effective in improving the healing of bDD lesions (HR 1.79, CI 1.12–2.88). The time to healing was also improved in inactive lesions (HR 2.19, CI 1.42–3.37). Conversely, the time to healing was delayed in feet receiving hoof-trimming (HR 0.41, CI 0.26–0.62), in cows with a contralateral bDD lesion (HR 0.32, CI 0.22–0.46) or in late lactation (HR 0.61, CI 0.43–0.85), and finally in farms with more than 100 cows (HR 0.48, CI 0.34–0.67). These findings reinforce the crucial role of hygiene in bDD dynamics and highlight the importance of implementing multiple control measures simultaneously, such as hygiene improvements in the barn, early detection and treatment of bDD lesions and the correct usage of individual and collective treatments. The implementation of Pink-Step™ represents a promising strategy for reducing the persistence of bDD lesions in affected herds.

International audience; Lameness in dairy cattle is an important health and welfare concern directly affecting the economic benefits of farmers. Although foot dirtiness is a recognized risk factor for diseases inducing lameness, there is a lack of scoring systems that focus specifically on the foot. Therefore, the aim of this study was to evaluate the reliability of a 3-point dirtiness scoring system recently conceived for the assessment of the dirtiness present at the lower legs and claws of dairy cows. The scores of both the lateral and back views from 4 unfamiliar raters at 4 different times were used to evaluate interrater reliability (3 times) and intrarater scoring consistency (1 time). The findings of this investigation revealed that coefficients for interrater agreement (0.38, 0.62 and 0.63) and rating concordance (0.55, 0.75 and 0.74) of back-view scorings improved over time and were superior or similar to those obtained from lateral-view evaluations (coefficients for interrater agreement = 0.20, 0.35, and 0.69; coefficients for rating concordance = 0.48, 0.59, and 0.78). Additionally, the scoring consistency of the raters using the back-view grid was excellent (Cronbach's α = 0.93). The results suggest that the 3-point back-view dirtiness scoring grid may provide dairy consultants and farmers a reliable and easy tool for assessing cow foot dirtiness.

Bovine digital dermatitis (DD), is a highly prevalent disease among dairy cattle characterized by ulcerative and painful lesions. While multiple management factors are involved in the disease, its precise etiology remains uncertain and the effectiveness of current control strategies remains highly variable. The major role ofTreponemaspp. in the development of the disease is consistently recognized. Nevertheless, it remains unclear how other bacterial communities are relevant to the onset and progression of the disease, and how the skin microbiota is affected by the environment during the course of the disease. The objective of this study was to describe the dynamics of microbiota recovered from DD affected feet under field conditions. This study described the diversity, structure, and composition of DD lesion microbiota over 45 days according to different clinical and management factors. The results of this investigation confirmed the existence of a specific skin microbiota associated with DD lesions, dominated byTreponemaspp. and very different from the microbiota of healthy skin. Interestingly, the diversity and structure of the microbiota in DD lesions did not vary with the footbath disinfectant or the individual topical antibiotic treatments used. In addition, microbiotas from proliferative lesions evidenced a different structure and diversity in comparison to non-proliferative lesions. Our results confirm the major role ofTreponemaspp. And highlight the potential role ofMycoplasmopsisspp. in the DD lesion onset. Further studies are needed to confirm whether the clinical course of DD lesions is driven by a particular microbiota and how that microbiota may induce disease.HighlightsMultiple bacteria have been identified in DD lesions. However, many of these microorganisms are inhabitants of the foot skin and the farm environment. For the first time, the microbiota of DD lesions was monitored for 45 days under field conditions to describe its evolution over time. The results of this investigation highlighted a particular microbiota dominated byTreponemaspp. present on the skin of DD affected animals and highly different from those microbiotas of healthy skin. The microbiota of DD lesions evolved over the study period and differential bacteria were identified. Further studies are warranted to determine the role of the bacteria composing these microbiotas on lesion onset and outcome.

International audience; Mycobacterium avium ssp. paratuberculosis (MAP) is the etiological agent of paratuberculosis, a disease that affects ruminants worldwide. Despite global interest in the control of this disease, gaps exist in our knowledge of fecal shedding patterns and concurrent serological patterns. This longitudinal study in dairy cattle herds with high MAP seroprevalence in France aimed at accurately describing fecal shedding patterns over 1 year; relating those shedding patterns to individual animal characteristics (age, breed, parity); and exploring the association between fecal shedding patterns and serological patterns. To describe temporal fecal shedding patterns and continuity of shedding, along with the standard quantitative PCR (qPCR) threshold cycle we used a cutoff value that related to low or nonculturable fecal shedding. We also defined a threshold cycle indicative of shedding in high quantities to describe infection progression patterns. Twenty-one herds completed the study, and 782 cows were tested 4 times each. We obtained 4 sets of paired fecal qPCR and serum ELISA results from 757 cows. Although we targeted highly likely infectious animals, we found a large diversity of shedding patterns, as well as high variability between herds in the proportion of animals showing a given pattern. The fecal qPCR results of almost 20% of the final study sample were positioned at least once in the range that indicated low or nonculturable fecal shedding (between the adjusted and the standard cutoff value). Although these animals would typically be classified as non-shedders, they could be important to infection dynamics on the farm. Animals that shed at least twice consecutively and animals that shed in high quantities rarely reverted to negativity. Repeated fecal qPCR can be used to detect temporal fecal shedding traits, and the decision to cull an animal could practically be based on temporal, semiquantitative results. Overall, we found a mismatch between fecal shedding and ELISA seropositivity (637 animals were ELISA-negative 4 times, but only 13% of those animals were qPCR-negative 4 times). We found that having more than 2 ELISA-positive samples was strongly related to persistent and continuous shedding. We suggest that although serological testing is much less sensitive than qPCR, it can also be used, particularly over the course of multiple testing events, to identify animals that are most likely to contribute to the contamination of the farm environment

International audience; Footbaths represent a potentially useful strategy for the prevention of claw infectious diseases by treating a large number of animals concomitantly. Nevertheless, under field conditions, footbath solutions are exposed to increasing number of animal passages and therefore, to different volume losses and concentrations of manure contamination which could alter their presumed bactericidal activity. Across increasing number of cow passages, the organic matter (OM) concentration, the microbial load (ML) and the residual volumes were assessed in six commercial farms. The results indicate that the OM concentration and ML increased linearly with the number of passages of animals, and with the number of defecations in the footbath. The OM concentrations and the ML were not impacted by the farm’s feet hygiene status (clean, fair and dirty), suggesting that probably the increasing number of cow passages and defecations influenced more the contamination of footbaths than the hygiene of the feet. In all the farms the volumes decreased drastically after 200 cow passages (50%). The OM concentrations after 150 and 200 cow passages did not exceed the regulatory concentrations in which disinfectant products should demonstrate to still be effective (20 g/l), and coincide with the often advised renewal rates. The findings of this study suggested that beyond the footbath contamination by OM, the renewal rates must be mainly adapted according to the remaining volume to guarantee that the entire foot is covered and therefore assure the topical action of the solution. This study highlights the importance of footbath designs for the successful implementation of these strategies in practice

Actinobacillosis usually is a sporadic infection that affects the tongue in cattle (“wooden tongue”) with possible spread to the digestive tract. Two 4-year-old Rouge-des-Prés cows from a single French beef herd were referred for chronic (2-6 months) swelling and cutaneous nodules in the distal hind limbs. In addition to cutaneous signs, physical examination disclosed cachexia, lameness, lymphadenitis of the hind limbs, and pneumonia in both cows. Cytologic examination of direct skin smears was inconclusive, and no parasites were observed in examination of multiple skin scrapings. Histopathological examination of skin and lung biopsy specimens identified chronic, diffuse, severe pyogranulomatous dermatitis, associated with Splendore-Hoeppli phenomenon and intralesional Gram-negative bacteria. Cultures from skin, lymph nodes, and lungs (both cows were euthanized for welfare reasons) identified a Pasteurellaceae organism, confirmed as Actinobacillus lignieresii by partial sequencing of the rpoB gene. This report emphasizes that actinobacillosis can appear as a small outbreak in cattle with cutaneous and respiratory signs.

International audience; High-immune quality colostrum (IgG1 concentration ⩾50 g/l) is crucial for the health and development of the young calf. Studies oncolostrum quality tend to focus on external factors such as breed, parity or dry period length, but few have focused on within-cowvariations. Here we ran experiments to gain a deeper insight into within-cow variation in IgG1 concentrations in dairy cow colostrum.Trials were performed in an experimental farm, located in the Western part of France. Colostrum from each quarter and a compositesample (mix of four quarters) were concomitantly collected on 77 Holstein dairy cows just after calving to assess the influence of sampletype on IgG1 concentrations. Variation in IgG1 concentrations during the first milking was studied on samples from nine cows collectedevery minute from the start of milking. Repeatability of colostral IgG1 concentration was estimated from 2009 and 2010 data on16 healthy cows. IgG1 concentrations were tested using a radial immunodiffusion method. Sensitivity and specificity were similarregardless of sample type tested (individual quarter or composite milk). Mean average IgG1 concentration was 54.1 g/l in compositecolostrum, and was significantly higher in hind quarter teats (56.2 g/l) than front quarter teats (53.1 g/l). Average IgG1 concentration didnot change significantly during colostrum milking, and the variations observed (15% or less) were likely due to the laboratory method(CV 15%). IgG1 concentrations in dam colostrum increased slightly from 2009 to 2010 due to BW and parity effects. In 56% of cases,colostrum quality could have been assessed on either individual or composite colostrum samples collected at any time during the firstmilking without affecting the reliability of the measurement. However, in other cases, differences were significant enough to mean thatestimates of average IgG1 concentration in colostrum from any one quarter would not be reliable. It is concluded that colostrum quality,from an IgG1 concentration point of view, could be assessed with a composite sample taken at any time during the first milking.

Hereditary spastic paraplegias (HSPs) are clinically and genetically heterogeneous human neurodegenerative diseases. Amongst the identified genetic causes, mutations in genes encoding motor proteins such as kinesins have been involved in various HSP clinical isoforms. Mutations in KIF1C are responsible for autosomal recessive spastic paraplegia type 58 (SPG58) and spastic ataxia 2 (SPAX2). Bovines also develop neurodegenerative diseases, some of them having a genetic aetiology. Bovine progressive ataxia was first described in the Charolais breed in the early 1970s in England and further cases in this breed were subsequently reported worldwide. We can now report that progressive ataxia of Charolais cattle results from a homozygous single nucleotide polymorphism in the coding region of the KIF1C gene. In this study, we show that the mutation at the heterozygous state is associated with a better score for muscular development, explaining its balancing selection for several decades, and the resulting high frequency (13%) of the allele in the French Charolais breed. We demonstrate that the KIF1C bovine mutation leads to a functional knock-out, therefore mimicking mutations in humans affected by SPG58/SPAX2. The functional consequences of KIF1C loss of function in cattle were also histologically reevaluated. We showed by an immunochemistry approach that demyelinating plaques were due to altered oligodendrocyte membrane protrusion, and we highlight an abnormal accumulation of actin in the core of demyelinating plaques, which is normally concentrated at the leading edge of oligodendrocytes during axon wrapping. We also observed that the lesions were associated with abnormal extension of paranodal sections. Moreover, this model highlights the role of KIF1C protein in preserving the structural integrity and function of myelin, since the clinical signs and lesions arise in young-adult Charolais cattle. Finally, this model provides useful information for SPG58/SPAX2 disease and other demyelinating lesions., Author summary Hereditary spastic paraplegias (HSPs) are human neurodegenerative diseases mainly associated with lower extremity weakness and spasticity. Motor-sensory axons degeneration, implying heterogeneous cellular and molecular mechanisms and various genetic causes, is the neuropathological hallmark of this disease. Recently, mutations in KIF1C were associated with human spastic paraplegia type 58 (SPG58) and spastic ataxia 2 (SPAX2), where the radiological brain examination showed demyelination features. We report herein that progressive ataxia of Charolais cattle, a neurodegenerative disease with autosomal recessive inheritance, is caused by a substitution in the KIF1C gene, which leads to a functional knock-out. Interestingly this mutation is associated, in a heterozygous state, with a better muscular development, and thus a zootechnic advantage. Identification of the mutation will therefore be helpful to eradicate this disease. Further study of the lesions in ataxic bovine central nervous system highlighted a peculiar link to oligodendrocytes which were hypertrophied and harbored many membrane protrusions. The demyelinating plaques were enriched by these membranes and actin accumulation indicating close relationship between KIF1C, actin transport and axonal wrapping by oligodendrocyte tongues. Since kif1c knock-out mouse do not display any neurological symptoms, progressive ataxia of Charolais cattle thus provides a useful model for studying SPG58/SPAX2 and other demyelinating diseases.

SUMMARYA study was carried out, from 2012 to 2015, in 10 Frenchdépartementsto estimate the serological prevalence of Q fever and the frequency of abortive episodes potentially related toCoxiella burnetiiin a large sample of cattle, sheep and goat herds. The serological survey covered 731 cattle, 522 sheep and 349 goat herds, randomly sampled. The frequency of abortive episodes potentially related toC. burnetiiwas estimated by investigating series of abortions in 2695 cattle, 658 sheep and 105 goat herds using quantitative polymerase chain reaction analyses and complementary serological results when needed. The average between-herd seroprevalence was significantly lower for cattle (36·0%) than for sheep (55·7%) and goats (61·0%) and significantly higher for dairy herds (64·9% for cattle and 75·6% for sheep) than for meat herds (18·9% for cattle and 39·8% for sheep). Within-herd seroprevalence was also significantly higher for goats (41·5%) than for cattle (22·2%) and sheep (25·7%). During the study period, we estimated that 2·7% (n= 90), 6·2% (n= 48) and 16·7% (n= 19) of the abortive episodes investigated could be ‘potentially related toC. burnetii’in cattle, sheep and goat herds, respectively. Overall, strong variability was observed betweendépartementsand species, suggesting that risk factors such as herd density and farming practices play a role in disease transmission and maintenance.

Chantier qualité GA; Recently, the French National Institute for Agricultural Research appointed an expert committee to review the issue of pain in food-producing farm animals. To minimise pain, the authors developed a ‘3S’ approach accounting for ‘Suppress, Substitute and Soothe’ by analogy with the ‘3Rs’ approach of ‘Reduction, Refinement and Replacement’ applied in the context of animal experimentation. Thus, when addressing the matter of pain, the following steps and solutions could be assessed, in the light of their feasibility (technical constraints, logistics and regulations), acceptability (societal and financial aspects) and availability. The first solution is to suppress any source of pain that brings no obvious advantage to the animals or the producers, as well as sources of pain for which potential benefits are largely exceeded by the negative effects. For instance, tail docking of cattle has recently been eliminated. Genetic selection on the basis of resistance criteria (as e.g. for lameness in cattle and poultry) or reduction of undesirable traits (e.g. boar taint in pigs) may also reduce painful conditions or procedures. The second solution is to substitute a technique causing pain by another less-painful method. For example, if dehorning cattle is unavoidable, it is preferable to perform it at a very young age, cauterising the horn bud. Animal management and constraint systems should be designed to reduce the risk for injury and bruising. Lastly, in situations where pain is known to be present, because of animal management procedures such as dehorning or castration, or because of pathology, for example lameness, systemic or local pharmacological treatments should be used to soothe pain. These treatments should take into account the duration of pain, which, in the case of some management procedures or diseases, may persist for longer periods. The administration of pain medication may require the intervention of veterinarians, but exemptions exist where breeders are allowed to use local anaesthesia (e.g. castration and dehorning in Switzerland). Extension of such exemptions, national or European legislation on pain management, or the introduction of animal welfare codes by retailers into their meat products may help further developments. In addition, veterinarians and farmers should be given the necessary tools and information to take into account animal pain in their management decisions.

The collective treatment (CT) of an affected herd is commonly advised to control bovine digital dermatitis (DD). Several CT are commercialized, frequently without major evidence supporting their effectiveness. The objective of this systematic review was to evaluate the published evidence that supports CT in the treatment and prevention of DD lesions in dairy herds. Across the evidence, the main limitations in the studies design were identified and the possible sources of inconsistency were investigated. An extensive literature search of publications through electronic databases and gray literature was conducted between July 2015 and January 2016. Studies that did not include an untreated or placebo control group were excluded from the review. The literature search and screening process identified 13 publications with 24 treatment trial comparisons and 18 prevention trial comparisons. The published evidence included studies mostly considered to have a low or unclear risk of bias. Descriptive analyses were performed according to the prevention and treatment outcomes, and case and success definitions were identified for each study and summarized in odds ratios (OR). Pairwise meta-analyses were conducted according to the prevention and treatment outcomes, comparing directly the intervention used in each study, and ignoring any other differences in the intervention characteristics. The results of the meta-analyses indicated a low degree of heterogeneity across the evidence for the prevention outcome [I2 = 0%, 95% CI: 0 to 37.2%, 95% prediction interval (PI): 0.72 to 1.74)] and a moderate degree for the treatment outcome (I2 = 25.3%, 95% CI: 0 to 63%, 95% PI: 0.39 to 3.73). Similarly, appraisal of the graphical L'Abbe plot suggested a considerable degree of heterogeneity across the evidence for the treatment outcome. For both outcomes, the frequent small sample sizes of the trials indicate imprecision across the included studies. Additionally, for the treatment and prevention outcomes, an asymmetric funnel plot suggested possible publication bias. The overall quality of the evidence, for both outcomes (prevention and treatment), was therefore considered to be low, indicating that the true effect of CT may be substantially different from that estimated across the included studies. Consequently, this review and meta-analysis does not support an association between the CT considered in the review and a beneficial effect in the prevention and treatment of DD lesions. The effectiveness of CT therefore remains uncertain, and the epidemiological circumstances in which it can be useful must be investigated. These findings highlight the importance of developing high quality, controlled trials to evaluate the effectiveness of CT for DD control.

Since 2007, mortality associated with a previously unreported haemorrhagic disease has been observed in young calves in several European countries. The syndrome, which has been named 'bovine neonatal pancytopenia' (BNP), is characterised by thrombocytopenia, leukocytopenia and a panmyelophthisis. A herd-level case-control study was conducted in four BNP affected countries (Belgium, France, Germany and the Netherlands) to identify herd management risk factors for BNP occurrence. Data were collected using structured face-to-face and telephone interviews of farm managers and their local veterinarians. In total, 363 case farms and 887 control farms were included in a matched multivariable conditional logistic regression analysis. Case-control status was strongly associated with the odds of herd level use of the vaccine PregSure r BVD (PregSure, Pfizer Animal Health) (matched adjusted odds ratio (OR) 107.2; 95% CI: 41.0-280.1). This was also the case for the practices of feeding calves colostrum from the calf's own dam (OR 2.0; 95% CI: 1.1-3.4) or feeding pooled colostrum (OR 4.1; 95% CI: 1.9-8.8). Given that the study had relatively high statistical power and represented a variety of cattle production and husbandry systems, it can be concluded with some confidence that no other herd level management factors are competent causes for a sufficient cause of BNP occurrence on herd level. It is suggested that genetic characteristics of the dams and BNP calves should be the focus of further investigations aimed at identifying the currently missing component causes that together with PregSure vaccination and colostrum feeding represent a sufficient cause for occurrence of BNP in calves.

The objective of the current study was to quantify the change in the prediction of dry matter intake (DMI) resulting from the inclusion of rumination time (RT) in the 2001 National Research Council (NRC) DMI prediction model. Forty-one Holstein cows fed the same total mixed ration were involved in a 10-wk study. Individual DMI were measured daily. The accuracy and precision of the original NRC prediction model, based on body weight, fat-corrected milk, and week of lactation as independent variables, was compared with the accuracy and precision of the same model with RT as an additional independent variable. The RT estimate was significant in the model developed but had a low value (0.031 kg/h). Root mean square prediction errors were very similar in the 2 models (1.70 and 1.68 kg/d) as were the other indicators (R(2), linear bias, random error, and concordance correlation coefficient) selected to compare the models in this study. These results indicate no gain in DMI prediction precision or accuracy when RT is included in the NRC model.

Les décisions de gestion de la santé animale correspondent à un large éventail de situations et de problèmes. Illustrant ce constat, sept maladies majeures des troupeaux bovins laitiers sont examinées pour identifier les facteurs les plus courants limitant l’efficacité des plans de maîtrise ainsi que les perspectives d’amélioration de la maîtrise sur le terrain. Pour les infections intra-mammaires, la recherche vise à la mise au point de vaccins multivalents, le ciblage des vaches à traiter par les antibactériens, la méthodologie des interventions en ferme, et l’augmentation de la résistance innée par la sélection génomique. Pour les strongyloses gastro-intestinales, les recherches prioritaires s’orientent aussi vers les stratégies de traitement anthelminthique raisonné et ciblé, la voie génétique semblant moins prioritaire que chez les petits ruminants. La maîtrise de la maladie de Mortellaro, affection de l’appareil locomoteur, ne pourra plus recourir aux désinfectants classiquement utilisés dans les pédiluves et des approches alternatives sont nécessaires. La maîtrise de la fièvre Q est à rechercher par la vaccination de l’ensemble du troupeau sur plusieurs années et l’hygiène de la parturition. La paratuberculose pourrait à terme être maîtrisée par la sélection génomique, en raison de l’absence de traitement et de vaccin efficaces et de l’existence de bases génétiques de résistance/résilience prometteuses. La maîtrise de l’infection par le virus BVDV semble pouvoir être atteinte par des mesures sanitaires combinées ou non avec la vaccination. La quasi-éradication des sérotypes exotiques du virus de la fièvre catarrhale ovine pourrait être obtenue par la surveillance ciblée et la vaccination massive et rapide. Les spécificités de l’étiologie, de l’épidémiologie et des moyens de maîtrise des maladies étudiées n’autorisent guère de conclusions génériques, Decisions in animal health management depend on a large variety of situations and problems. To illustrate this, seven major diseases of dairy herds were analysed to identify the main limiting factors for the effectiveness of the current control schemes and the perspectives toward better control in the field. Regarding intramammary infections, research directions focus on the development of multivalent vaccines, tools to better select cows to be treated with antibiotics, on-farm intervention methodology and the enhancement of animal resistance via a contribution of genome-wide selection techniques. For gastro-intestinal strongyloses, priority was also given to rational and selective anthelmintic treatments, genetic improvement of innate resistance seeming less a priority than for small ruminants. The control of Mortellaro disease, a locomotor disorder, should receive attention to develop alternatives because of the forecasted ban of the principal disinfectants used for footbaths. Q fever control can be reached by prolonged vaccination of the whole herd and adequate management of parturition hygiene. Johne disease is probably a good candidate disease for genomic selection, especially given the absence of treatment and very effective vaccine and the presence of a quite promising background of resistance/resilience. Infection by BVDV seems to be controllable by only sanitary measures, associated or not with a vaccination scheme. Eradication of exotic serotypes of BTV can be reached by targeted surveillance and quick and massive vaccination. Specificities in etiology, epidemiology and control techniques of the diseases under study do not quite allow drawing generic conclusions.

A controlled field trial was conducted to evaluate in dairy cattle the benefit provided by different regimens of a collective topical treatment using a solution of copper and zinc chelates to cure digital dermatitis (DD) compared with individual treatment alone, and further to investigate factors that could explain variations in the clinical cure of DD lesions over 6 mo. The study was conducted between November 2009 and October 2010 and involved 4,677 dairy cows from 52 French dairy farms on which DD was endemic. The farms were quasi-randomly allocated to 1 of 4 treatment regimens for 6 mo: no collective treatment (control), walk-through footbath during 4 consecutive milkings every 4 wk (FB/4W) or every 2 wk (FB/2W) and collective spraying during 2 milkings every 2 wk (CS/2W). For ethical and welfare reasons, all farmers also had to treat all detected active DD lesions with individual topical spraying of oxytetracycline. Digital dermatitis and leg hygiene were scored on all lactating cows during milking 7 times every 4 wk by 14 trained investigators. During these farm visits, data related to farm management were also collected. The curative effectiveness of collective treatments was assessed through a Cox survival frailty model as the probability of cure of an active DD lesion during at least 2 consecutive visits. The model was adjusted for farm and cow risk factors as well as initial DD prevalence. Monthly DD cure rates were 58, 55, 76, and 76% in the control, FB/4W, FB/2W, and CS/2W regimens, respectively. The spontaneous monthly cure rate for untreated active DD lesions was 61%. Hazard of cure of DD was increased by 1.28 and 1.41 when walk-through footbath and collective spraying, respectively, were applied over 2 d every 2 wk compared with the control regimen. Applying a walk-through footbath 2 d every 4 wk was not sufficient to improve the cure of DD compared with individual treatments alone. Three main factors were identified as speeding DD healing: cleanliness of the feet, initial small size of the DD lesion, and additional individual topical treatment. Grazing tended to speed DD healing. These results highlight the need of combining several control measures, including individual and collective topical treatments, and improving foot hygiene and the early detection of DD lesions to ensure a high cure rate and rapid curing of digital dermatitis on endemically affected farms.

SUMMARYThe relationship between the level of antibodies in bulk tank milk (BTM) and the within-herd seroprevalence of Coxiella burnetii in cows was assessed. Blood from milking cows and BTM were sampled in 55 infected herds and tested using commercial enzyme-linked immunosorbent assay (ELISA) kits. The relationship between antibody levels and WHP, which was quantified using a general linear model, was only moderate (R2=0·15). Nevertheless, the lowest antibody level in BTM was associated with the lowest mean within-herd prevalence. The present finding indicates that ELISA applied to BTM could identify infected herds with quite low within-herd seroprevalence. For such herds, the vaccination of dairy cows as well as nulliparous heifers using a phase I vaccine could effectively prevent C. burnetii shedding.

International audience; Enteric and respiratory diseases are the most frequent health disorders of calves. They are associated with mortality or lower growth rate and induce treatment costs. Enteric and respiratory pathogens can be transmitted via contacts between calves, which depend on calf housing systems and management. This study aimed at describing the main calf housing systems across Europe and at assessing the consequences of such housing facilities in terms of risk for calf infectious diseases. This was done through the use of a questionnaire distributed to experts in epidemiology and cattle farming systems in each European country. A literature review was performed on the risk factors associated with calf infectious diseases transmission and targeted in the questionnaire. Answers from 14 countries were obtained. A wide range of housing systems were described. However, four main systems could be identified and ranked in ascending order of risk for neonatal diarrhoea and respiratory infectious diseases: individual pen until weaning, individual pen for 4 weeks, individual pen for 2 weeks, and collective pen from the separation of the calf with its dam. Although the housing systems are known to play a role in disease transmission, they are currently not fully described in literature concerning risk factors for calf infectious diseases. In a given farm, the risk assessment for calf infectious diseases should consider classical risk factors such as hygiene, feeding practices and air conditioning, on top of a precise description of the housing system.

International audience; Q fever is a worldwide zoonosis that may cause reproductive disorders such as abortion, endometritis or infertility in livestock. The implementation of a vaccination with a phase I vaccine is the nowadays the most relevant way to control the spread of the infection within herds. Annual boosters are recommended for ruminants by the manufacturer whereas in humans, to prevent side effects, no booster must be done before 5 years and the lack of humoral and cellular immunity has to be confirmed before any additional vaccination. The aim of this study was to investigate, in dairy cattle, the interest of such annual booster by assessing the level of different immune markers among 142 animals (from infected and uninfected herds) vaccinated either 2 year (i.e. 2 times) or 1 year before with an efficient commercial phase I Q fever vaccine. One year after vaccination, more than 80 % of the vaccinated cows had still immune markers, whereas 68 % of the heifers from uninfected herd did not. These data suggested that an annual booster would not be necessary for all vaccinated animals within a herd. In order to detect the immune animals and then to optimize the number of animals needing a boost, the skin test method, performed at least 3 days before the vaccination could be used. (C) 2009 Elsevier B. V. All rights reserved

International audience; While shedding routes of Coxiella burnetii are identified, the characteristics of Coxiella shedding are still widely unknown, especially in dairy cattle. However, this information is crucial to assess the natural course of Coxiella burnetii infection within a herd and then to elaborate strategies to limit the risks of transmission between animals and to humans. The present study aimed at (i) describing the characteristics of Coxiella burnetii shedding by dairy cows (in milk, vaginal mucus, faeces) in five infected dairy herds, and at (ii) investigating the possible relationships between shedding patterns and serological responses. A total of 145 cows were included in a follow-up consisting of seven concomitant samplings of milk, vaginal mucus, faeces and blood (Day 0, D7, D14, D21, D28, D63, D90). Detection and quantification of Coxiella burnetii titres were performed in milk, vaginal mucus and faeces samples using real-time PCR assay, while antibodies against Coxiella were detected using an ELISA technique. For a given shedding route, and a given periodicity (weekly or monthly), cows were gathered into different shedding kinetic patterns according to the sequence of PCR responses. Distribution of estimated titres in Coxiella burnetii was described according to shedding kinetic patterns. Coxiella burnetii shedding was found scarcely and sporadically in faeces. Vaginal mucus shedding concerned almost 50% of the cows studied and was found intermittently or sporadically, depending on the periodicity considered. Almost 40% of cows were detected as milk shedders, with two predominant shedding patterns: persistent and sporadic, regardless of the sampling periodicity. Significantly higher estimated titres in Coxiella burnetii were observed in cows with persistent shedding patterns suggesting the existence of heavy shedder cows. These latter cows were mostly, persistently highly-seropositive, suggesting that repeated serological testings could be a reliable tool to screen heavy shedders, before using PCR assays.

Caprine-like Generalized Hypoplasia Syndrome (SHGC) is an autosomal-recessive disorder in Montbéliarde cattle. Affected animals present a wide range of clinical features that include the following: delayed development with low birth weight, hind limb muscular hypoplasia, caprine-like thin head and partial coat depigmentation. Here we show that SHGC is caused by a truncating mutation in the CEP250 gene that encodes the centrosomal protein C-Nap1. This mutation results in centrosome splitting, which neither affects centriole ultrastructure and duplication in dividing cells nor centriole function in cilium assembly and mitotic spindle organization. Loss of C-Nap1-mediated centriole cohesion leads to an altered cell migration phenotype. This discovery extends the range of loci that constitute the spectrum of autosomal primary recessive microcephaly (MCPH) and Seckel-like syndromes., SHGC syndrome affects cattle and has clinical features similar to human Seckel syndrome. Here Floriot et al. identify the causative mutation in the centrosomal protein C-Nap1 that affects centriole cohesion and cell migration, extending the range of loci involved in human Seckel-like syndromes.

Different tests performed on bulk tank milk samples (BTM) are available to determine the C. burnetii status of herds. However, these tests, which are based on the detection of either antibodies directed against C. burnetii (ELISA) or bacterial DNA (PCR), have limitations. A currently disease-free herd infected in the past may continue to test positive with ELISA due to the persistence of antibodies in animals that were infected and that subsequently cleared the infection. Infectious herds can also be misclassified using PCR because of the absence of bacteria in the BTM when the test is performed. Recently, PCR has been used for bacterial DNA detection in the farm environment, which constitutes the main reservoir of C. burnetii. The objectives of this study were to assess and compare the sensitivities and specificities of one commonly used PCR test in BTM (PCR BTM) and of a PCR applied to environmental samples (PCR DUST) in dairy cattle farms. BTM and dust samples were collected (using environmental swabs) in 95 herds. The evaluation of the performance of the 2 tests was conducted using latent class models accounting for within herd disease dynamics. Parameter estimation was carried out using MCMC, within a Bayesian framework. Two types of priors were used for the specificity of PCR DUST. A model with a uniform prior on 0–1 fitted the data better than a model with a uniform prior on 0.95–1. With the best model PCR DUST had a lower sensitivity than PCR BTM (0.75 versus 0.83) and a specificity of 0.72. The moderately low value for the specificity of PCR DUST suggests that the presence of bacteria on farm is not always associated with persistent infections and shedding of bacteria in milk.

National audience; Ruminants are sentient beings, endowed with emotional and cognitive abilities, which can perceive different types of pain (nociceptive or neuropathic) in different types of contexts (breeding / experimentation). Assessing pain is often difficult because, in most situations of pain, there is not a unique and specific indicator but rather a set of complementary indicators. An accurate assessment of pain is essential to optimize care and use of the therapeutic arsenal currently available to prescribers. Indeed, the therapeutic arsenal with different mechanisms of action, it is necessary to quantify pain intensity and the type of pain assessment. Through this review, we will show how: i) accurate assessment is essential for optimal management of pain, ii) method of assessment depends on the type of pain that is suspected and can be based on a multiparametric approach, a limited number, or even a single indicator as appropriate.; Les ruminants sont des animaux sensibles, doués de capacités émotionnelles et cognitives, pouvant être soumis à différents types de douleur (excès de nociception ou neuropathique) et ceci dans différents contextes (élevage/expérimentation). L’évaluation de ces douleurs est bien souvent délicate car, pour la plupart des cas, il n’existe pas d'indicateur unique et spécifique mais plutôt un ensemble d'indicateurs dont les valeurs informatives sont souvent complémentaires. Une évaluation adéquate de la douleur est essentielle afin d'optimiser sa prise en charge et utiliser au mieux l'arsenal thérapeutique actuellement à la disposition des prescripteurs. En effet, les molécules ayant des mécanismes d’action différents, il est nécessaire de pouvoir quantifier l’intensité douloureuse et évaluer le type de douleur mis en cause. A travers cette synthèse, nous montrerons en quoi : i) l’évaluation du type et du niveau de douleur est indispensable à une prise en charge optimale de la douleur, ii) qu’une évaluation reposant sur une approche multiparamétrique est la plus adaptée à notre objectif.

International audience; Reliable detection of Coxiella burnetii shedders is a critical point for the control of the spread of this bacterium among animals and from animals to humans. Coxiella burnetii is shed by ruminants mainly by birth products (placenta, birth fluids), but may also be shed by vaginal mucus, milk, and faeces, urine and semen. However, the informative value of these types of samples to identify shedders under field conditions is unknown. Our aim was then to describe the responses obtained using a real-time PCR technique applied to milk, vaginal mucus and faeces samples taken from 242 dairy cows in commercial dairy herds known to be naturally infected with Coxiella burnetii, and to assess their putative associations. Positive results were found in all types of tested samples even in faeces. No predominant shedding route was identified. Among the shedder cows, 65.4% were detected as shedders by only one route. By contrast, cows with positive results for all three samples were scarce (less than 7%). Testing a cow based on only one type of biological sample may lead to misclassify it with regards to its shedding of Coxiella burnetii and thereby underestimate the risk of bacterial spread within a herd.

International audience; This study aimed to catalogue the digital dermatitis (DD) treatment practices used by French dairy farmers and to identify the motivators and barriers to the adoption of these treatments. A semi-structured survey was conducted involving 65 farmers in the main dairy production areas of France in the spring of 2009. The different treatment modalities implemented by farmers since the first diagnosis of DD in their herds were described. The reasons for adopting or abandoning these treatments were then investigated based on criteria of perceived effectiveness, labour; time, cost and toxicity related to their use. For individual treatments, farmers used 30 different products, applied through three different routes, for 1 to 21 consecutive days. For collective treatments, farmers used 31 products, applied through four different routes, at a rate ranging from once a day to once a year. Several products, especially antibiotics, were used without observing the manufacturer's instructions. The principal criteria for the adoption of a treatment was the perceived effectiveness in healing DD lesions and in limiting recurrence, while the principal barriers to adopting a treatment were the time and labour required for its application, followed by cost. Topical oxytetracycline treatments applied individually were used and adopted the most. They were perceived to be effective in healing DD lesions. However, these treatments were judged labour and time consuming, particularly when many animals had to be treated. Collective treatments combining formalin and copper sulphate often were applied topically using walk-though footbaths. These treatments often were judged to be insufficiently effective in healing DD lesions, difficult to implement, labour and time consuming and costly. The plethora of DD treatment practices and the misuse of some treatments could suggest that there is a lack of guidelines available to farmers on the optimal use and expected effectiveness of treatments. Clinical trials should be conducted to develop recommendations based on scientific rather than empirical data, and to identify the DD control measures which consume the least amount of time and labour.

Chantier qualité GA; One important objective for animal welfare is to maintain animals free from pain, injury or disease. Therefore, detecting and evaluating the intensity of animal pain is crucial. As animals cannot directly communicate their feelings, it is necessary to identify sensitive and specific indicators that can be easily used. The aim of the present paper is to review relevant indicators to assess pain in several farm species. The term pain is used for mammals, birds and fish, even though the abilities of the various species to experience the emotional component of pain may be different. Numerous behavioural changes are associated with pain and many of them could be used on farms to assess the degree of pain being experienced by an animal. Pain, as a stressor, is associated with variations in the hypothalamic-pituitary-adrenal axis as well as in the sympathetic and immune systems that can be used to identify the presence of pain rapidly after it started. However, most of these measures need sophisticated equipment for their assessment. Therefore, they are mainly adapted to experimental situations. Injuries and other lesional indicators give information on the sources of pain and are convenient to use in all types of situations. Histopathological analyses can identify sources of pain in experimental studies. When pronounced and/or long lasting, the pain-induced behavioural and physiological changes can decrease production performance. Some indicators are very specific and sensitive to pain, whereas others are more generally related to stressful situations. The latter can be used to indicate that animals are suffering from something, which may be pain. Overall, this literature review shows that several indicators exist to assess pain in mammals, a few in birds and very few in fish. Even if in some cases, a single indicator, usually a behavioural indicator, may be sufficient to detect pain, combining various types of indicators increases sensitivity and specificity of pain assessment. Research is needed to build and validate new indicators and to develop systems of pain assessment adapted to each type of situation and each species.

Q fever is an ubiquitous zoonosis caused by an resistant intracellular bacterium,Coxiella burnetii. In certain areas, Q fever can be a severe public health problem, and awareness of the disease must be promoted worldwide. Nevertheless, knowledge ofCoxiella burnetiiremains limited to this day. Its resistant (intracellular and environmental) and infectious properties have been poorly investigated. Further understanding of the interactions between the infected host and the bacteria is necessary. Domestic ruminants are considered as the main reservoir of bacteria. Infected animals shed highly infectious organisms in milk, feces, urine, vaginal mucus, and, very importantly, birth products. Inhalation is the main route of infection. Frequently asymptomatic in humans and animals, Q fever can cause acute or chronic infections. Financial consequences of infection can be dramatic at herd level. Vaccination with inactive whole-cell bacteria has been performed and proved effective in humans and animals. However, inactive whole-cell vaccines present several defects. Recombinant vaccines have been developed in experimental conditions and have great potential for the future. Q fever is a challenging disease for scientists as significant further investigations are necessary. Great research opportunities are available to reach a better understanding and thus a better prevention and control of the infection.