Nicolas Masset

Le suivi de reproduction sera abordé de façon différente selon le fonctionnement de la reproduction de l’élevage. Le regroupement des vêlages doit, de façon générale, être recherché pour améliorer les performances de l’élevage. Il facilite également le déroulement du suivi. Ainsi, au cours de la campagne, les visites se succèdent avec des thèmes différents, correspondant au stade physiologique des vaches au moment de la visite. Les contenus du suivi de reproduction doivent inclure le suivi de la période de vêlage, la préparation de la mise à la reproduction (taureau inclus), les diagnostics de gestation et la rédaction de bilans pour les différentes périodes suivies. Le suivi des veaux et de l’élevage des génisses permet également la mise à la reproduction de futures mères productives, c’est-à-dire fertiles et capables d’élever leur veau. Les points clés ou outils permettant la maîtrise de la reproduction des vaches allaitantes sont également évoqués.

Background: Acute infectious bronchopneumonia is widely reported in adult cattle, yet most descriptions focus on postmortem findings. Hypothesis/Objectives: To describe signalment, clinical, hematological, and ultrasonographic findings in affected cows, and to identify pathogens and clinical findings associated with outcome. Animals: Twenty-one cows from 11 farms. Methods: Prospective case series. All cows underwent clinical examination, thoracic ultrasonography, bronchoalveolar lavage for culture and PCR, and CBC. Thoracic ultrasonography was repeated to assess lesion dynamics after antibiotic treatment. Outcomes were classified as favorable (clinical recovery and maintained milk production) or unfavorable (death or reduced milk production leading to premature drying-off and early culling). Descriptive statistics were computed, and univariate analyses were performed to identify variables associated with outcome. Results: Mean age at inclusion was 47 months (range, 24-104). Cases occurred mainly in winter (10/21) and during the early postpartum period (10/21); 17/21 were dairy cows. Typical clinical signs associated with acute respiratory disease (coughing, wheezes, and crackles) were rarely observed. Thoracic ultrasonography revealed frequent consolidations (17/21) and pleural effusion (13/21), with lesion size decreasing over time. Mannheimia haemolytica and Pasteurella multocida were identified by PCR in bronchoalveolar lavage samples in 13/21 and 18/21 cases, respectively. Unfavorable outcomes (11/21) were associated with nasal discharge, left shift on CBC, reduced ruminal contractions, higher respiratory rate on day 0, and deeper consolidation lesions on days 0 and 5. Conclusions and clinical importance: Ultrasonography is a valuable cow-side tool that supports diagnosis and provides key information on the clinical course of acute infectious bronchopneumonia in adult cows.

Les praticiens rapportent depuis quelques années une augmentation des cas de bronchopneumonies infectieuses chez les bovins adultes. Les données épidémiologiques confirment une incidence croissante, avec un rôle prédominant de Mannheimia haemolytica dans les formes aiguës. Le diagnostic reste difficile, car les signes cliniques sont souvent discrets et non spécifiques lors de l’examen initial. L’échographie thoracique constitue un examen complémentaire pertinent, permettant d’objectiver des lésions de consolidation pulmonaire et des épanchements pleuraux présents dès l’évaluation initiale. Le lavage broncho-alvéolaire est la technique de prélèvement de choix pour établir un diagnostic étiologique fiable sur le terrain. Plusieurs critères simples associés à l’évolution des cas ont été identifiés : une fréquence respiratoire élevée, la présence d’un jetage et une profondeur importante des lésions de consolidation lors du diagnostic initial sont associées à une évolution défavorable (mort, chute de production nécessitant un tarissement précoce ou une réforme anticipée). L’ensemble des données disponibles souligne l’importance d’un diagnostic précoce et d’une prise en charge rapide, afin d’optimiser les chances de guérison et de pronostic favorable.

Omphalitis is the third most frequent disease in newborn calves after neonatal diarrhea and bovine respiratory disease (BRD), but limited data on the prevalence and risk factors are available in the literature. Failure of passive immunity transfer (FPIT) is recognized as a major risk factor for diseases and mortality in calves. However, the association between omphalitis and FPIT remains poorly described. To assess this association, 964 suckler beef calves from 22 farms were included in a longitudinal cohort study for 5 months. Each calf was examined twice (mean ages: 4.4 and 11.1 days old) to diagnose omphalitis through clinical examination and ultrasonographic evaluation (USE) if necessary. Measurements of the total solids percentage (TS-%Brix) and total protein (TP) were performed on the serum during the first visit to evaluate the calves’ passive immunity status. FPIT (fair and poor) was defined as serum %Brix < 8.1 or TP < 5.1 g/dL; among calves with omphalitis, 14% had FPIT and among calves without omphalitis 12% had FPIT. The omphalitis prevalence was 32.3% in calves without any other disease (overall prevalence of 30.9%). No statistical association between the prevalence of omphalitis and FPIT was observed. Further research is needed to identify the risk factors and promote the prevention measures for omphalitis in cow–calf systems, such as calving difficulty, hygiene of housing, and navel disinfection.

Background: In the veal calf industry, bovine respiratory disease is the main cause of morbidity and mortality. Lung ultrasonography (LUS) is an accurate technique to diagnose bronchopneumonia in calves. Due to the economic constraints faced by the industry, a screening technique able to rapidly examine large numbers of calves is required.Objective: To determine if lung ultrasonography focusing on the cranial part of the thorax (1st to 2nd intercostal space (ICS) on the right and 2nd to 3rd on the left) and/or on the middle part of the thorax (3rd to 5th ICS on the right and 4th to 5th on the left) (alternative techniques) are rapid screening techniques as sensitive as LUS of the entire lung (reference technique) to identify calves with lung consolidation lesions.Methods: Data on 300 veal calves aged 33.1 ± 8.0 days and weighing on average 67.5 ± 4.0 kg at LUS from two farms were analysed. Systematic LUS of the entire lung was performed on all calves and a lung consolidation score was given to different parts of the thorax. Agreements between the alternative and the reference techniques were measured by Cohen's κ, McNemar's test and weighted κ.Results: Agreement between LUS focusing on the cranial + middle part or on the cranial part only of the thorax and the reference technique were almost perfect with a cutoff of 1 cm. The relative sensitivity of these two alternative techniques was high (> 93%).Conclusion: Lung ultrasonography of the cranial + middle part or on the cranial part only of the thorax are quick and sensitive techniques to identify veal calves with lung consolidation lesions shortly after arrival at the facility.