Efikasnost različitih formulacija lambda-cihalotrina u suzbijanju iksodidnih krpelja

Ticks (Acari:Ixodida) are arthropods of special biomedical importance, well known as transmitters of several zoonotic diseases. Various acaricides have been used to control them but their number has decreased over the years. Having this in mind, we examined in 2003-2005 the possibility of using a 5% microemulsion and an EC formulation of lambda-cyhalothrin to control ticks on dogs and sheep, and in houses. The 5% microemulsion of lambda-cyhalothrine caused tick mortality after 2-3 minutes. The efficacy of the 5% EC formulation of lambda-cyhalothrin was unsatisfactory.Krpelji (Acari:Ixodida) su artropode poznati kao vektori mnoštva zoonotskih oboljenja. Parazitiraju tokom hranjenja na sisarima, pticama i gmizavcima. Suzbijaju se primenom širokog spektra akaricida čiji se broj svake godine sve više ograničava. Imajući to u vidu tokom 2003-2005. godine izvršena su ispitivanja mogućnosti primene 5% mikroemulzije i EC formulacije lambda-cihalotrina u svrhu suzbijanja krpelja. Primenom 5% mikroemulzije lambda-cihalotrina dolazilo je do uginuća krpelja u roku 2-3 minuta. Efekat EC formulacije nije dao zadovoljavajuće rezultate

Prévalence et les facteurs du risque pour la toxoplasmose chez les porcs et caractérisation d'évolution d'infection naturelle en modèle des porcs

The parasite from the phylum Apicomplexa, Toxoplasma gondii is adapted for infection of all warm-blooded animals including humans. Postnatal infection occurs through ingestion of i) tissue cysts present in muscles of infected animals, or ii) environmentally resistant forms - oocysts via contaminated water, fruits and vegetables. Disease is generally benign, but infection may have serious consequences for the developing foetus in the case of maternal infection in pregnancy and in immunosuppressed individuals. Along with sheep and poultry, T. gondii parasites are mostly isolated from pig meat. In intensive systems with various levels of confinement, intensity of T. gondii infection is still considerably lower than in outdoor or organic farms throughout Europe. Poor rodent control and presence of cats on intensive farms are major sources of T. gondii infection for pig. When straw is used for bedding, it can contain oocysts or even rodent carcasses, and if the food silos or distributers are opened, pig nutrition can be contaminated. In contrast to intensive farming, in outdoor and organic farms, pigs are exposed to environmental T. gondii contamination through soil, food, and water sources. So far, routine surveillance of pigs for T. gondii infection has not been established anywhere in the World, neither in the slaughterhouse nor on the farm-levels. Thus the sources of pig infection on the farms are still unknown. Moreover, it is unknown how big the role of the meat from T. gondii infected pigs is in human nutrition...Dans le phylum des Apicomplexa le parasite Toxoplasma gondii est adapté à l'infection de tous les animaux à sang chaud y compris l'homme. L'infection se produit après la naissance par l'ingestion de kystes i) présents dans les muscles des animaux infectés, ou ii) des formes résistantes de l'environnement – les oocystes contaminants l'eau, les fruits et légumes, les coquillages. La maladie est généralement bénigne, mais l'infection peut avoir des conséquences graves pour le développement du fœtus dans le cas de l'infection maternelle pendant la grossesse et chez les individus immunodéprimés.Hormis les muscles et organes de moutons et de volaille, le parasite T. gondii est principalement isolé de la viande de porc. Dans les systèmes intensifs avec différents niveaux de confinement, l'intensité de l'infection par T. gondii est toujours considérablement plus basse que dans les élevages en plein air ou biologique pour toute l'Europe. L’absence de lutte contre les rongeurs et la présence de chats dans les exploitations intensives est les principales sources de l'infection par T. gondii chez le porc. Lorsque la paille est utilisée comme litière, elle peut contenir des oocystes ou carcasses de rongeurs, et si les silos ou les distributeurs d’alimentation sont ouverts, l'alimentation du porc peut être contaminée. Contrairement à l'agriculture intensive, dans les exploitations en plein air ou ayant le statut de « porc biologique » les animaux sont exposés à une contamination environnementale par T. gondii (pâture, nourriture et eau). Jusqu'à présent, la surveillance systématique des porcs vis à vis de l'infection par T. gondii n'a été établie dans aucun pays et il n’existe pas de contrôle à l'abattoir ou à la ferme (même si une visite sanitaire a été instaurée en 2015 en France). Aussi, les sources d'infection dans les élevages restent méconnues et le rôle de la viande de porc dans la contamination humaine est à définir...

Experimental Toxoplasma gondii infections in pigs: Humoral immune response, estimation of specific IgG avidity and the challenges of reproducing vertical transmission in sows

Ten pregnant sows were experimentally inoculated per os with T. gondii in order to investigate vertical and galactogenic transmission of the parasite and the evolution and maturation of the specific IgG humoral response in the sows and piglets. Five seronegative sows received 10(4) T. gondii (CZ isolate clone H3) sporulated oocyts during late-pregnancy (Exp. 1), three sows received 10(4) oocysts during mid-pregnancy (Exp. 2) and three sows from Exp. 1 (and two seronegative sows) were re-inoculated with 10(5) oocysts during a further pregnancy (late-pregnancy) (Exp. 3). Besides, six 4.5 week-old piglets inoculated per os with 5 x 10(3) oocysts were also included in the serological investigations. All animals seroconverted (PrioCHECK Toxoplasma Ab porcine ELISA, Prionics, Switzerland) by 2-3 weeks post inoculation (wpi) and remained seropositive for at least 38 weeks or until euthanasia. Four chronically infected sows from Exp. 1 and 2 were serologically monitored during a further pregnancy and no reactivation, but a decrease of the antibody levels was observed at farrowing (Exp. 4). In all experiments, the specific IgG-avidity was initially low, increased during the course of infection and after re-inoculations. An avidity index (AI) >= 40% could be used to rule out recent infections (<8 weeks) in most (15 of 16) animals. In some piglets (18.6% of 70) delivered by inoculated sows (Exp. 1 and 2), maternal antibodies were still detectable at 2 months (but not by 3 months) of age, with constant high avidity values, comparable to those of the dams at farrowing. In all experiments, the sows remained asymptomatic and delivered non-infected offspring at term. A total of 208 normal and 5 stillborn piglets delivered by the inoculated sows (Exp. 1-4) tested serologically negative before colostrum uptake. Placentas (n = 88) from all sows and tissues (brain, liver, lung, heart, and masseter muscle) from 56 delivered piglets were analysed histopathologically and by real-time PCR for T. gondii with negative results. Colostrum and milk samples from all sows were negative by real-time PCR for T. gondii DNA. In addition, no seroconversion was observed in 16 piglets from seronegative dams that were transferred to infected dams one day after birth to detect a possible infection through colostrum or milk during the suckling period. Although vertical transmission of T. gondii was demonstrated in naturally infected pigs, many factors involved in the outcome of vertical transmission and congenital toxoplasmosis in pigs are still unknown

The Use of Flocked Swabs with a Protective Medium Increases the Recovery of Live Brucella spp. and DNA Detection

International audienceIn order to protect public and veterinary health from highly zoonotic bacteria such as members of the genus Brucella and prevent their dissemination into the environment, direct diagnostics are of utmost importance. However, in addition to the highly specific diagnostic tests, the sampling methods, time necessary for specimens to reach the laboratories, and transport conditions are important factors to consider in order to increase the sensitivity of performed tests, especially bacterial culturing and qPCR

Molecular Investigations of Two First <i>Brucella suis</i> Biovar 2 Infections Cases in French Dogs

Despite Brucella suis biovar 2’s (BSB2) active circulation in wildlife, no canine infections have been reported. The present paper is the first to describe two cases of BSB2 infections in French dogs. The first case occurred in 2020 and concerned a 13-year-old male neutered Border Collie with clinical signs of prostatitis. The urine culture revealed the excretion of significant levels of Brucella in the sample. The second case concerned a German Shepherd with bilateral orchitis, in which it was possible to detect Brucella colonies following neutering. HRM-PCR and classical biotyping methods classified both isolated strains as BSB2, in contrast to expected B. canis, which is usually the etiological agent of canine brucellosis in Europe. The wgSNP and MLVA analyses highlighted the genetic proximity of two isolates to BSB2 strains originating from wildlife. No pig farms were present in the proximity of either dog’s residence, ruling out potential spill over from infected pigs. Nevertheless, the dogs used to take walks in the surrounding forests, where contact with wildlife (i.e., wild boars or hares, or their excrements) was possible. These cases highlight the importance of adopting a One Health approach to control the presence of zoonotic bacteria in wild animals and avoid spillovers into domestic animals and, potentially, humans

Effect of Toxoplasma gondii on ram semen fertilizing capacity after experimental infection

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Evaluation of a Lateral Flow Immunochromatography Assay (LFIA) for Diagnosis and Surveillance of Brucellosis in French Alpine Ibex (Capra ibex)

International audienceFrance has been officially free of bovine brucellosis since 2005. Nevertheless, in 2012, as the source of two human cases, a bovine outbreak due to B. melitensis biovar 3 was confirmed in the French Alpine Bargy massif, due to a spillover from wild, protected Alpine ibex (Capra ibex). In order to reduce high Brucella prevalence in the local ibex population, successive management strategies have been implemented. Lateral flow immunochromatography assay (LFIA) was thus identified as a promising on-site screening test, allowing for a rapid diagnosis far from the laboratory. This study compared a commercial LFIA for brucellosis diagnosis with the WOAH-recommended tests for small ruminants (i.e., Rose Bengal test (RBT), Complement fixation test, (CFT) and Indirect ELISA, (iELISA)). LFIA showed the same analytical sensitivity as iELISA on successive dilutions of the International Standard anti-Brucella melitensis Serum (ISaBmS) and the EU Goat Brucella Standard Serum (EUGBSS). Selectivity was estimated at 100% when vaccinated ibex sera were analyzed. When used on samples from naturally infected ibex, LFIA showed high concordance, as well as relative sensitivity and specificity (>97.25%) in comparison with RBT and CFT. This work shows high reliability and ensures a better standardization of LFIA testing for wild ruminants

Étude de la contamination par Toxoplasma gondii desviandes ovines, bovines et porcines – résultats des plansde surveillance pour les années 2007, 2009 et 2013

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Evaluation of immunogenicity and protection of the Mic1-3 knockout Toxoplasma gondii live attenuated strain in the feline host

International audienceToxoplasmosis is a zoonotic disease caused by the parasite Toxoplasma gondii. Up to a third of the global human population is estimated to carry a T. gondii infection, which can result in severe complications in immunocompromised individuals and pregnant women. Humans and animals can become infected by ingesting either tissue cysts containing T. gondii bradyzoites, from raw or undercooked meat, or sporulated oocysts from environmental sources. T. gondii oocysts are released in the faeces of cats and other felids, which are the parasite's definitive hosts, leading to environmental contamination. Therefore, vaccination of the feline host against T. gondii is an interesting strategy to interrupt the parasitic life cycle and subsequently limit contamination of intermediate hosts. With this goal in mind, we tested in cats, an attenuated live strain of T. gondii deleted for the Mic1 and Mic3 genes (Mic1-3KO) that was previously shown to be an efficient vaccine candidate in mouse and sheep models. Subcutaneous or oral vaccination routes induced a high specific antibody titer in the cat sera, indicating that the Mic1-3KO strain is immunogenic for cats. To assess protection induced by the vaccine candidate strain, we followed oocysts shedding by vaccinated cats, after oral challenge with a T. gondii wild-type strain. Surprisingly, a high antibody titer did not prevent cats from shedding oocysts from the challenge strain, regardless of the vaccination route. Our results show that the Mic1-3KO vaccine candidate is immunogenic in the feline host, is well tolerated and safe, but does not confer protection against oocysts shedding after natural infection with wild type T. gondii. This result highlights the particular relationship between T. gondii and its unique definitive host, which indicates the need for further investigations to improve vaccination strategies to limit environmental and livestock contaminations

The emergence of Brucella canis as a public health threat in Europe: what we know and what we need to learn

ABSTRACTThe zoonotic bacteria, Brucella canis, is becoming the leading cause of canine brucellosis in Europe. In dogs, it causes reproductive problems as well as non-specific lameness or discospondilitis. In humans, B. canis can be origin of chronic debilitating conditions characteristic to its genus such as undulant fever, splenomegaly, and lymphadenopathy. Although B. canis shows some pathogenic characteristics similar to B. abortus and B. melitensis, it lacks surface O-polysaccharide, like nonzoonotic B. ovis. This review shows that host–B. canis interactions are still poorly understood, with many knowledge and capability gaps, causing relatively poor sensitivity and specificity of existing diagnostic tools. Currently, there is no vaccine for this rough Brucella species. Besides, antimicrobial therapy does not guarantee bacterial elimination, and infection relapses are frequently reported, increasing the risks of antibiotic resistance development. B. canis has been detected in dogs in almost all European countries which increased human exposure, but currently there is no systematic surveillance. Moreover, B. canis caused brucellosis is not included in Animal Health Law, and therefore there is no legal framework to tackle this emerging infectious disease. To map out the diagnostic strategies, identify risks for human infections and propose management scheme for infected pet and kennel dogs, we present current understanding of canine B. canis caused brucellosis, outline major knowledge gaps and propose future steps. To address and highlight challenges veterinary and public health services encounter in Europe, we developed two B. canis infection scenarios: of a single household pet and of a kennel dog in larger group