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Animal welfare enhancement requires that problems are reliably identified and ranked in order to prioritise corrective actions. Welfare problems vary with the conditions in which animals are maintained. The objectives were to highlight major welfare problems for dairy cows on farms in France, and find out how farm characteristics (housing and milking systems, breed) could impact specific welfare aspects on these farms. We conducted a cross-sectional survey on 131 French dairy farms. We used the Welfare Quality® protocol, which addresses all aspects of welfare, and yields scores for principles and criteria that represent how well farms meet welfare requirements (from 0 for a very adverse situation to 100 for an excellent one). We used descriptive statistics to highlight low welfare scores, and variance analyses to compare farms. Most farms were found ‘Acceptable’ according to the Welfare Quality® classification. Principles scores for Health, Feeding and Behaviour ranged from 33 to 39. The median score for eight of the welfare criteria was below 50 (‘Pain’, ‘Integument alterations’, ‘Diseases’, ‘Comfort around resting’, ‘Social behaviours’, ‘Human-animal relationship’, ‘Positive emotional state’, ‘Hunger’), while the median score was above 50 for the four other criteria (‘Thirst’, ‘Lameness’, ‘Expression of other behaviours’, ‘Ease of movement’). The scores varied widely between farms, within and between systems. Farms with cubicles obtained lower scores for ‘Comfort around resting’, ‘Injuries’; farms with Holstein cows obtained lower scores for ‘Hunger’; farms using an automatic milking system obtained lower scores for ‘Expression of other behaviours’ and ‘Diseases’ in Holstein herds. This survey yields information on bottlenecks in dairy cow welfare with all dimensions of welfare considered together. The results can be used by stakeholders to prioritise corrective actions in welfare plans, focusing either on the whole population of farms or on farms with characteristics that are at high risk for specific welfare problems.

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.

The purpose of this study was to concurrently estimate the effect of different digital dermatitis (DD) treatment regimens and herd management practices on the occurrence of a new DD lesion. A controlled clinical trial was conducted and involved 4678 dairy cows from 52 French dairy farms where DD was endemic. Farms were allocated by minimisation to one of 4 treatment regimens, varying through the mode (footbath or collective spraying) and the frequency of application (2 days every 4 weeks or fortnightly). They were visited 7 times every 4 weeks by 14 trained investigators. Frailty Cox proportional hazards models were used to estimate the relative effect of potential risk factors and treatment practices on the time until the first occurrence of a DD lesion. At herd level, high initial DD prevalence strongly increased the risk for DD occurrence (HR=1.93, CI 1.23-3.04), as well as absence of hoof-trimming (HR=1.75, CI 1.36-2.27) and poor leg cleanliness (HR=2.44, CI 1.80-3.31). At animal level, Holstein breed (HR=1.92, CI 1.35-3.57) and high-productive cows (HR=1.26, CI 1.01-1.56) were identified to be at higher risk for DD compared to Normande breed and low-productive cows, respectively. Compared to individual topical antibiotic treatments alone, collective treatments tended to decrease the risk of DD occurrence only when applied over 2 days at least every fortnight (HR range=0.64-0.73).

International audience; Extensive information is available in the literature on the specific risk factors of the main health disorders afflicting dairy cattle herds. However, it remains difficult to manage a herd's overall health because measures to control one risk factor can exacerbate the risk of another disease. To achieve and maintain good overall herd health, livestock systems and management practices need to simultaneously take into account all of the main health disorders. We aimed to identify the characteristics of systems and practices conducive to good herd health using the Welfare Quality® assessment protocol for cattle. This protocol allows an assessment of the level of health and welfare at the herd level according to the opinion of a selected group of 13 experts from animal sciences. Our objectives were to (i) describe the distribution of dairy herds’ health scores in a representative sample of French dairy cattle herds, and (ii) to investigate systems (housing system, milking system, herd size, breed, farm location) and management practices associated with variations of the overall health score of dairy herds. This protocol was carried out on 130 farms between December 2010 and March 2011. A multivariable analysis of variance (ANOVA) was performed to investigate the factors of variation of the overall health score at the herd level. The overall health scores of the farms in the sample were classified as moderate for the vast majority of farms (95.4%) (mainly due to subclinical mastitis, dystocia and pain induced by disbudding/dehorning) and varied little between farms. Some livestock systems were associated with a higher overall health score: straw yards and milking parlors (P < 0.0001), highland vs. lowland locations (P = 0.013), Montbeliarde rather than Holstein breeds (P = 0.006). Some management practices also were associated with a higher level of health: medium herd average parity (P = 0.03), low proportion of dirty cows (P = 0.002) and low proportion of cows with abnormal body condition (P = 0.04). These results suggest that some systems contribute to better health and that improvement of health can be obtained in the short term by the modification of routine management practices.

Measurement of the immunoglobulin G concentration of dairy cow colostrum. A study was conducted to see if the concentration of colostral immunoglobulin G (IgG) in Holstein dairy cows differed according to the sampling method. Concentrations of IgG were measured by radial immune-diffusion (RID). Three sampling regimens were tested: composite sample, single sample and time of sampling. IgG was measured in: a composite sample (taken from the 4 quarters of the udder at first milking in 78 cows),in a single sample (taken from 1 quarter at first milking in 78 cows) or in several samples, 7 to 9 samples taken through out the duration of first milking in 9 cows, to test a potential ‘time of sampling’ effect. In conclusion, at the level of 50 g/L, which is considered to be “good quality” or acceptable colostrum, the concentration of IgG was unaffected by sampling time or sampletype. Based on the calves’ capacity to drink, observed in the present study, it is recommended that 2 to 4 L of colostrum be consumed within 2 hours of birth and that colostrum should be collected preferably from the posterior quarters. The quantity given is crucial due to the quality of dairy cow colostrum.; Une étude a été menée pour savoir si l’évaluation de la teneur en immunoglobulinesG (IgG) du colostrum chez la vache laitière Prim’Holstein différait, selon qu’elle se réalisait sur un échantillon de lait composite des quatre quartiers issus de la première traite (pratique courante), sur le lait issu d’un seul quartier, ou à plusieurs moments de la première traite. La teneur en IgG a été mesurée sur 78 vaches par immuno-diffusion radiale(IDR), à la fois sur un échantillon prélevé de la première traite des 4 quartiers(lait composite) et sur un échantillon des autres quartiers. De plus,9 vaches ont fait l’objet de 7 à 9 prélèvements en cours de première traite pour évaluer un effet potentiel « moment du prélèvement ». Il ressort qu’au seuil de 50 g/L pour considérer un colostrum de « bonne qualité »ou de qualité acceptable, il n’y avait aucune influence ni du moment de prélèvement, ni du type de prélèvement, sur la mesure de la teneur enIgG. Compte tenu de la capacité de buvée des veaux observée dans l’étude, il peut être recommandé de donner 2 à 4 litres dans les 2 premières heures de vie du veau, le colostrum pouvant être collecté préférentiellement des quartiers postérieurs. La quantité administrée est cruciale en raison de la qualité des colostrums de vaches laitières.

The effectiveness of the vaccination of dairy cows combined or not with antibiotics (i.e. oxytetracycline) to control Coxiella burnetii (Cb) shedding at herd level was investigated in 77 Q fever clinically affected herds. In addition to nulliparous heifers' vaccination, one out of the four following medical strategies was randomly assigned to dairy cows in each herd: vaccination (using a phase I vaccine) alone, vaccination combined with oxytetracycline, oxytetracycline alone or nothing. Their effectiveness to reduce Cb load in quarterly samples of bulk tank milk (BTM) and of pooled milk of primiparous (MP) was assessed through logistic hierarchical models. A significant reduction in Cb load was observed in herds where the vaccination of ≥80% of dairy cows was implemented; whereas the use of antibiotics was uneffective. Our findings support the interest of a whole vaccination strategy and provide evidence for decreasing the use of antibiotics in dairy cattle herds.

International audience

International audience

Effectiveness of phase 1 vaccine, combined or not with tetracycline, to control Coxiella burnetii vaginal shedding at calving in cows was assessed through a 13 months study in 22 Q fever clinically affected commercial dairy herds. Four medical strategies implemented at herd level but randomly assigned to cows (vaccination, vaccination and tetracycline, tetracycline, nothing) were compared. There was no significant interaction effect between vaccination and antibiotherapy. Tetracycline used once at drying off was associated with a lower risk of being detected shedder at calving (OR=0.40, CI 95% [0.21-0.75]), but had no significant effect on the bacterial load shed. Vaccination did not significantly prevent shedding but was significantly (OR=0.15, CI 95% [0.03-0.85]) associated with lower bacterial load shed. Thus, vaccination using a phase 1 vaccine and antibiotherapy using tetracycline is associated with a decrease in shedding in dairy cows and could contribute to reduce the bacterial load generated in the environment. To the best of our knowledge, this is the first study providing useful information for evidenced-based and rational use of medical strategy combining antibiotic and vaccination in infected dairy cattle herds.

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.

To describe both shedding and serological patterns following abortions detected as being associated with Coxiella burnetii (Cb), 24 cows experiencing an abortion due to Cb were followed over a one month period. Samples taken on the day of abortion (D0) were followed 3-fold by weekly samplings from day 14 (D14) to D28 after the abortion. Milk and vaginal mucus were collected at each weekly sampling and tested using real-time PCR while blood samples were collected 2-fold on D21 and D28 and tested using ELISA. We found a very short duration of C. burnetii shedding in vaginal mucus after abortion, highlighting the need to collect samples as rapidly as possible following an abortion to avoid false negative results. In contrast with previous results, concomitancy of vaginal and mucus shedding was frequent, especially for cows shedding a high bacterial load on DO leading to the hypothesis that the clinical onset of the infection influences the modalities of Cb shedding. Lastly, serological results indicating a lack of sensitivity to detect Cb shedder cows (especially for cows for which Ct values were high) suggest that ELISA is not a useful tool to diagnose abortions at the individual level.

International audience; Reliable detection of Coxiella burnetii is a critical point for the control of the spread of this zoonotic disease (Q fever), ruminants being considered as the main source for human infection as confirmed by the recent human outbreak in the Netherlands since 2007. Considering both public and animal health, providing consolidated prevalence data could be relevant within the decision process of public policy makers or producers organizations. The objective of this study was to conduct a critical review of the literature focused on the prevalence of C. burnetii infection at animal, herd and within-herd levels in cattle, goat and sheep. A qualitative assessment of the 69 selected publications, based on the analysis of the sampling frame and testing procedures, was also performed. While the number of publications increased recently, major methodological issues were still evidenced. These critical issueswere related to (i) the absence of description of the sampling strategy and (ii) the lack of sensitivity of the testing procedure. The lack of well designed studies makes not possible to estimate accurately the current prevalence of the infection. Nevertheless, the literature review reported the detection of C. burnetii infection in the all 5 continents with a wide range whatever the species. The apparent prevalence was slightly higher in cattle (20.0% and 37.7% ofmean apparent prevalence at animal and herd level respectively) than in small ruminants (around 15.0% and 25% respectively for animal and herd level in sheep and goat). The present conclusions and the current situation support the persistent need of conducting well designed studies, aiming at estimating the true prevalence of C. burnetii infection in the three main domestic ruminant species

a b s t r a c t Coxiella burnetii is the causal agent of Q fever, a worldwide spread zoonosis. Prevention of C. burnetii shedding in cattle is critical to control the spread of the pathogen between animals, and from animals to humans. Vaccination with a phase 1 vaccine has been shown to be effec- tive in preventing shedding when implemented in still susceptible animals, even in infected cattle herds. The identification of these animals (dairy cows and nulliparous females) as targets for vaccination consequently is crucial. Hygiene measures conventionally also are implemented, but their relative impact on C. burnetii diffusion remains unknown. The objectives of this study therefore were to (i) describe the distribution of the within-herd apparent seroprevalence among cows and nulliparous females and (ii) to explore the associ- ation between management practices and herd characteristics on the one hand, and these seroprevalences on the other. In a sample of 100 naturally and clinically infected dairy herds, blood samples were taken systematically from all nulliparous females (older than 12 months) and cows, and serologically tested. Information on herd characteristics and management practices were collected through a questionnaire filled in by each farmer. The variation in within-herd seroprevalence among cows and the risk for a herd of having at least one seropositive nulliparous female were investigated using multivariate (linear and logistic respectively) regression models. Median within-herd seroprevalence was 0.32 (Q1 = 0.22; Q3 = 0.43). We observed a low to null (median = 0.01; Q1 = 0; Q3 = 0.10) within- herd seroprevalence in nulliparous females contrary to a high value (median = 0.42) and variability (Q1 = 0.28; Q3 = 0.56) in cows. Only a few herd characteristics and management practices were found to be related to seroprevalence. Within-herd seroprevalence in cows was found to be significantly (P < 0.10) higher in herds (i) with a number of cows < 46, (ii) with seasonal calving, and (iii) with grazing or contact through the fence with other rumi- nant herds. The risk of having at least one seropositive nulliparous female was increased in herds (i) with seasonal calving and (ii) where the foetus and/or the placenta of aborted cows were not systematically removed. Our findings support, in addition to the implemen- tation of high level of hygiene measures, the relevance of vaccination (at least in nulliparous females) as a method to control the spread of C. burnetii within an infected herd, as vacci- nation is effective in susceptible animals and given that nulliparous females are mostly not infected even in infected herds.

Seventeen four- to five-week-old calves that were not shedding bovine respiratory syncytial virus (BRSV) were vaccinated intranasally against the disease and sampled by nasal swabbing on 16 different days for up to 20 days after vaccination. BRSV vaccine virus was detected in 15 of the 17 calves. Five of the calves were PCR positive on only one swab, eight were PCR positive on two to five swabs and two were PCR positive on more than five swabs. Twelve of the calves were positive only before day 14 and three were positive after day 14. The nasal shedding of BRSV vaccine virus was very variable.

Summary Thirty-seven bulk tank milk (BTM) and individual milk samples of all contributing cows were tested for Coxiella burnetii detection by a real-time PCR assay and used to assess the relationship between the BTM PCR-response and (i) the within-herd prevalence of milk-shedder cows and (ii) the proportion of heavy milk-shedder cows. The within-herd prevalence of milk-shedder cows (i) was found to be significantly higher in herds with a positive BTM and (ii) increased significantly with the estimated titre in Coxiella burnetii obtained in positive BTM. The proportion of heavy milk-shedder cows among the milk-shedder cows increased significantly with an increased estimated titre in Coxiella burnetii in positive BTM. Therefore, a real-time PCR assay applied to BTM samples collected repeatedly over time appears to be a valuable tool to assess on a larger scale the status of herds towards Coxiella shedding, and to evaluate the efficiency of control actions aimed at controlling and/or preventing Coxiella shedding in dairy herds.

National audience; In this literature review, we found that, in general, grazing improves cattle health and reduces cattle mortality. Grazing cattle were less likely to become infected with common livestock diseases: lameness and other foot/leg conditions; mastitis; metritis; respiratory problems; and certain cutaneous parasitoses (i.e., pulicosis, scabies, dermatophytosis). However, grazing can also increase certain health risks that farmers must learn to manage. These risks include endoparasitoses (caused by gastrointestinal strongyles); fly and tick infestations (which can increase the likelihood of infectious keratoconjunctivitis); bacterial diseases (e.g., ehrlichiosis, anaplasmosis); viral diseases (e.g., bluetongue disease, Schmallenberg disease); or protozoan diseases (e.g., babesiosis, theileriosis). Furthermore, cattle that graze on young grass plants are at increased risk for grass tetany, frothy bloat, and enterotoxemia.; De manière générale, le pâturage est bénéfique à la santé des bovins, en réduisant la fréquence des maladies les plus fréquentes : boiteries et affections des membres, affections de la mamelle, métrites ainsi que les troubles respiratoires et certaines parasitoses cutanées. Globalement, le pâturage diminue le risque de mortalité des bovins adultes. Mais il présente des risques spécifiques que l'éleveur doit apprendre à gérer : des parasitoses internes (strongles gastro-intestinaux), des infestations par les insectes (avec risques de kérato-conjonctivite infectieuse), de diverses maladies bactériennes, virales et de protozooses ; enfin, le pâturage de l'herbe jeune induit un risque pour la tétanie d'herbage, la météorisation spumeuse et les entérotoxémies, maladies rares mais souvent mortelles.

La dermatite digitée est une maladie enzootique dans de nombreux élevages bovins laitiers. Il s’agit d’une cause fréquente de boiterie et sa gestion est donc primordiale. Afin de donner aux éleveurs les moyens les plus adaptés pour gérer cette maladie, 52 exploitations laitières du grand Ouest ont été suivies toutes les 4 semaines pour un total de 8 visites. Des traitements collectifs à base de chélates de cuivre et de zinc (gamme Hoof Fit ®) ont été testés selon différentes fréquences (mensuelle et bimensuelle) et modalités d’application (pédiluve et pulvérisation en salle de traite). Les facteurs de variations de l’efficacité curative et préventive des traitements ont été recherchés par analyse de survie. Les résultats montrent qu’un traitement collectif bimensuel permet de mieux prévenir et guérir les lésions de dermatite digitée que ce soit par pédiluve ou par pulvérisation comparé à un traitement collectif mensuel ou à un traitement individuel des lésions détectées. Par ailleurs, de nombreux facteurs modifient l’efficacité préventive et curative des traitements. Les principaux sont : l’hygiène podale du troupeau, la prévalence initiale de la maladie dans le troupeau, le traitement topique individuel des lésions détectées à l’oxytétracycline, le stade initial de la lésion, le pâturage, la propreté du postérieur et le parage. Ainsi, des préconisations pourront être adaptées à chaque exploitation. Néanmoins les facteurs faisant varier l’hygiène podale semblent être nombreux et doivent encore être identifiés et étudiés afin d’optimiser les stratégies de traitement de la maladie de Mortellaro.