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International audience; Botulism type C was suspected in a 46-year old man after consumption of sick poultry from a flock where botulism type C was confirmed. The patient developed characteristic signs of botulism, but investigation of biological samples did not confirm the presence of Clostridium botulinum or botulinum toxin. Despite having classical botulism symptoms, the man recovered very quickly. This raises the question of botulism transmission to humans by ingestion of contaminated poultry.

Bluetongue virus (BTV) and epizootic haemorrhagic disease virus (EHDV) in deer have already been isolated in Reunion Island and have caused more or less severe clinical signs in cattle (EHDV) or in sheep (BTV), as observed in 2003. In January 2009, cattle in Reunion Island showed clinical signs suggesting infection by one or the other of these arboviral diseases. A study was set up to determine the etiology of the disease. Analysis by reverse transcriptase-polymerase chain reaction (RT-PCR) performed on blood samples from 116 cattle from different districts of the island detected the presence of the EHDV genome in 106 samples and, in 5 of them, the simultaneous occurrence of BTV and EHDV. One strain of EHDV (7 isolates) and one of BTV were isolated in embryonated eggs and a BHK-21 cell culture. Group and subgroup primer-pairs were designed on the segment 2 sequences available in GenBank to identify and type the EHDV strains. Phylogenetic analysis of the genomic segment 2 (encoding the VP2 serotype-specific protein) of the isolates confirmed the serotypes of these two orbiviruses as BTV-2 and EHDV-6 and allowed them to be compared with previously isolated strains.

International audience; The use of urinary cortisol (UC) as an additional tool to evaluate sows welfare was assessed in two experiments. In a preliminary methodological experiment, the kinetics of cortisol excretion in urine was studied during an Adreno Cortico Trophic Hormone (ACTH) challenge test in 10 pregnant sows. In a second experiment, 96 primiparous sows of an experimental unit were assigned to two different housing systems: 48 animals were housed in individual pens (IP) and 48 animals in collective pens (CP) with 6 animals per pen. UC was measured at the beginning and at the end of pregnancy and compared with other welfare indicators such as behaviour or skin damage. In both experiments, UC was measured using a high pressure liquid chromatography assay. In experiment 1, UC was constant on the day before injection of ACTH, with no variations related to circadian rhythm. It began to rise 2 h after the injection, peaked between 2 to 5 h after then returned to the basal concentration on the day after the injection. In experiment 2, UC concentrations were not different between CP- and IP-housed sows but they were higher in sows exhibiting the less stereotypies in comparison with sows exhibiting the most stereotypies. The results of this study suggest that UC is a good indicator of acute stress, more convenient than plasma cortisol measurement since it is a non-invasive method avoiding restraint or catheterisation of sows. They also suggest that UC could also give additional information on the assessment of chronic stress and improve the evaluation of animal welfare if used in conjunction with other welfare indicators.; Le cortisol urinaire comme critère d'évaluation supplémentaire du bien-être de la truie gravide dans deux systèmes de logement. L'intérêt du cortisol urinaire (CU) comme critère d'évaluation du bien-être des truies a été testé dans deux expériences. Dans une première expérience méthodologique, la cinétique d'excrétion du CU dans les urines de dix truies gravides a été mesurée suite à un test à l'hormone adrénocorticotrope (ACTH). Dans une deuxième expérience, 96 truies primipares d'une station expérimentale ont été réparties, pendant la gestation, dans deux systèmes de logement : 48 truies en stalles individuelles (SI) et 48 autres en cases collectives (CC) de 6 animaux. Leur CU a été mesuré en début et fin de gestation puis comparé aux autres critères d'évaluation du bien-être comme le comportement ou les blessures cutanées. Dans chacune des expériences, le CU a été dosé par une méthode de chromatographie liquide haute pression (HPLC). Dans la première expérience, aucun rythme circadien du CU n'a été observé le jour précédant le test à l'ACTH. Le CU a commencé à augmenter deux heures après l'injection d'ACTH, atteint un pic entre 2 et 5 h après puis est revenu à un taux de base le lendemain. Dans la deuxième expérience, le CU des truies logées en SI n'était pas différent de celui des truies logées en CC, mais le CU des truies exprimant le moins de stéréotypies était plus élevé que celui des truies en exprimant le plus. Le résultat de cette étude suggère que le dosage du CU est un bon indicateur de stress aigu, plus facile à mettre en pratique car il n'impose ni prise de sang ni cathétérisation des animaux. D'autre part, le CU est un critère supplémentaire dans l'évaluation du stress chronique et permet d'améliorer l'appréciation du bien-être animal lorsqu'il est associé à d'autres indicateurs.

A homologous vaccine against peste des petits ruminants (PPR) was investigated in northern Cameroon. The vaccine strain was the attenuated PPRV 75/1 strain. The cost-effectiveness of the vaccine was studied by vaccinating flocks of small ruminants kept in their traditional environment. After 1 year, the mortality rates of the flocks were compared with those of a control group. The results demonstrated that the mortality rates were significantly decreased in the vaccinated flocks. The annual benefit for the herder was estimated to be about 13 400 FCFA (about US$ 22) for a flock of 45 animals.

A mixed vaccine against peste des petits ruminants (PPR) and capripox infection was investigated in northern Cameroon. The vaccine strains were the attenuated PPRV 75/1 strain for PPR and the RM 65 strain for Capripox disease. 25 goats were vaccinated with different doses of the vaccine to study the seroconversion. In another experiment, 20 goats were vaccinated and then challenged with wild virulent strains of PPR and goat pox. The measure of the seroconversion as well as the challenge experiments demonstrated that PPR valence was effective at least till the 10 0.8 tissue culture infective dose 50. However, the capripox valence appeared not to be protective despite the apparition of neutralising antibodies. The economical benefits of using a low dose of vaccine against PPR are discussed. Further studies with new vaccinal strains of capripox viruses are recommended before investigating clinical field trials.

A survey was conducted in north and far-north provinces of Cameroon to determine the risk factors responsible for the appearance of clinical signs in small ruminants. Eight flocks, with a total of 141 animals, were visited weekly for 21 months by field agents who noted the appearance of individual clinical signs. The animals were weighed monthly and their faeces were collected for coproscopic examination. At the same time, their sera were tested against the following microbes: Mycoplasma mycoides subsp. mycoides LC, M. capricolum subsp. capricolum subsp. nove, M. agalactiae, M. capricolum subsp. capripneumoniae , Capripoxvirus and peste des petits ruminants (PPR) virus. The independent variables were province, season, species, sex, age class, presence of external parasites, infestation level by intestinal parasites and seroconversions. The survey emphasized the influence of species and season on nasal discharges (more frequent for sheep and in the cold dry season). The prevalence of contagious agalactia syndrome was higher for animals more than one year old and during the cold dry season; furthermore, it was strongly correlated with mycoplasma seroconversion. The seroconversion against PPR was concomitant with that against Capripoxvirus. Slow growth was associated with strongylosis infestation, the presence of external parasites and the PPR-Capripoxvirus seroconversion. Considering the high cost of vermifuges and insecticides, only a vaccination campaign appears to be suitable. Long-term control measures against parasitical diseases should focus on livestock practices. Hence, it is recommended to compare the productivity of flocks vaccinated with a mixed PPR-Capripoxvirus vaccine, and reared under different livestock conditions.

Mycoplasma mycoides subsp. mycoides LC and Mycoplasma ovipneumoniae were isolated for the first time from a goat in northern Cameroon. Experimental inoculation with M. mycoides subsp. mycoides LC induced death in two inoculated goats with pneumonic, arthritic and mastitic symptoms, whilst Mycoplasma ovipneumoniae was not pathogenic despite its multiplication in the upper respiratory tract (nasal sinuses). Following a single inoculation in a goat with both isolates, the course of the disease was not significantly modified. Mycoplasmaemia and the presence of mycoplasma in the milk were investigated. Necropsy observations of infected animals included areas of pulmonary hepatization with macroscopic thickening of the interlobular septa in one goat, and invasion of the lung by numerous small abscesses with no macroscopic thickening of the interlobular septa in the other animal. In both cases, white fibrinous plaques were present in the thoracic cavity but no pleural fluid was observed. It is recommended to pay particular attention to the diagnosis of M. mycoides subsp. mycoides LC infection in an area where contagious bovine pleuropneumonia is endemic and contagious caprine pleuropneumonia is threatening.

Eight hundred and ninety zebus from the north and far-north provinces of Cameroon were tested with two tuberculin assays to estimate the effect of infection by atypical mycobacteria on tuberculosis diagnosis in the region. Six hundred and seven of these animals were tested simultaneously against brucellosis with a delayed hypersensitivity test to brucellin (DHTB) and three standard serological assays as a comparison of the two classes of tests. The results demonstrated that only one quarter of the animals which were designated as tuberculous by the single tuberculin test were considered tuberculous by the comparative tuberculin test (CTT). For 34% of the CTT-reactive animals, borderline reactions were obtained and the results of the tests were uncertain. With regard to brucellosis, the relative sensitivity of the DHTB was 33%; the relative specificity was 96%. The limitation of the delayed hypersensitivity and serological methods are discussed. The most sensitive diagnostic procedure is a combination of both tests, where subjects are scored as positive if they are positive to either or both tests. The DHTB presents the advantage of requiring neither laboratory facilities nor animal identification.

Quatre troupeaux de zébus du nord-Cameroun, comprenant en tout 136 animaux, ont été vaccinés par voie sous-cutanée avec les doses suivantes de la souche B19 : 5 x 10 puissance 9 unités formant colonies (UFC), 10 puissance 9 UFC, 5 x 10 puissance 8 UFC et 10 puissance 7 UFC. Vingt-huit jours après la vaccination, les taux de séroconversion ont été respectivement les suivants : 97,4, 96,2, 84,2 et 73,3 %. Sur les 52 animaux, dont 39 âgés de plus d'un an le jour de la vaccination, ayant pu faire l'objet d'un contrôle sérologique ultérieur, 1 seul présentait des anticorps 6 mois après la vaccination. A la dose de 10 puissance 9 UFC, le coût de revient du vaccin B19 produit au Laboratoire national vétérinaire de Boklé est de 65 F CFA la dose ; à la dose habituellement préconisée de 5x10 puissance 10 UFC, il est de 1740 F CFA. Les différentes perspectives d'utilisation de la souche B19 dans la prophylaxie médicale contre la brucellose bovine au nord-Cameroun sont discutées.

Pour la première fois au Cameroun, une souche de Pasteurella multocida de sérotype B6 a été isolée d'un foyer de septicémie hémorragique sur des zébus dans la région de Maga (Province de l'Extrême-Nord du pays). Par une épreuve sur souris, il a été montré qu'il n'y avait pas de protection croisée entre cette souche et une souche de Pasteurella multocida de type E6 utilisée pour produire le vaccin contre la pasteurellose bovine au Cameroun. L'utilisation d'un vaccin mixte incluant les sérotypes E6 et B6 est donc recommandée pour les pays d'Afrique centrale et d'Afrique de l'Ouest.