{"id":"c1cde78c-d695-4d4b-be27-3a642da56f81","title":"Investigation of the contamination of raw milk by  Cryptosporidium spp. and evaluation of  contamination risk factors","year":2026,"publisher":"Université de Rouen-Normandie","excerpt":"Introduction\n\n\n\nCryptosporidiosis is a zoonotic disease affecting both humans and animals, and in particular young calves. Infectious neonatal diarrhea accounts for over 25% of veterinary visits to the farm, and is the main cause of mortality in calves under one month of age. Among etiologic agent o…","url":"https://rd-agri.fr/detail/DOCUMENT/c1cde78c-d695-4d4b-be27-3a642da56f81","links":{"self":"/rd-agri/documents/c1cde78c-d695-4d4b-be27-3a642da56f81"},"description":"Introduction\n\n\n\nCryptosporidiosis is a zoonotic disease affecting both humans and animals, and in particular young calves. Infectious neonatal diarrhea accounts for over 25% of veterinary visits to the farm, and is the main cause of mortality in calves under one month of age. Among etiologic agent of such infective diarrhea, Cryptosporidium spp. are one of the most frequent. Besides, outbreaks linked to raw-milk dairy products have been reported worldwide and also in France (2017, Nantes). This raises the questions of the probability of milk contamination when parasites are circulating on farms, and the practices that could lead to such contamination.\n\nObjectives\n\nThe objectives were: i) to investigate the potential Cryptosporidium contamination of milk on dairy farms in a context of parasite circulation in calves; ii) identify any practices that may pose a risk of milk contamination \n\nMaterials & Methods\n\nSampling was performed in volunteer dairy farms by veterinarians based on the detection of cryptosporidiosis in calves feces. Stool samples from calves and cows were sampled concomitantly with milk production. Samples (both stools and milk) were analysed by qPCR and positive samples were genotyped on the gp60 gene. If necessary, multi locus variant analysis (MLVA) were performed to distinguish same gp60 subtypes. A survey questionnaire based on risk factors’ hypothesis was designed and implemented in participating farms to compare the practises in farms depending on the milk contamination status (univariate statistical analysis). \n\nResults \n\nTo date, 69 dairy farms were sampled representing 225 stool samples and 85 milk samples analysed. Cryptosporidium DNA was detected from stool samples in 94% of the 69 sampled dairy farms. C. parvum, C. bovis, C. andersoni, C. ryanae and C. hominis Cryptosporidium species and 17 different gp60 genotypes were identified. Cryptosporidium DNA was detected in 13% (9/69) of sampled milk from the 69 dairy farms investigated with frequency depending on milk destination. From the 9 positive samples, all identified gp60 genotypes were different. Genotypes characterized in milk were also different from ones simultaneously identified in calves. According to DNA detection in milk, positive farms differed from negative farms in practices linked to milking hygiene, calf managements, and cleanliness of the cows bedding.\n\n\n\nConclusion\n\nCryptosporidium DNA was occasionally detected in milk, with a significant lower frequency in farms delivering/processing raw milk, indicating a higher control of pathogens from fecal origin. Cryptosporidium DNA detection does not inform on the infectivity of the parasite and the risk for consumers. Genotypes were mainly different from those circulating in calves, suggesting other routes of contamination or role of biofilms in the contamination of milk. Better control of hygiene measures in raw milk sector contribute to a better management of Cryptosporidium contamination.  ","language":"eng","keywords":[],"project":{"code":"20ART1531490","name":"Evaluation de la contamination du lait cru de vache par le parasite Cryptosporidium spp. et des pratiques associées dans un contexte de supposée circulation parasitaire"},"notice-url":null,"document-url":"https://rd-agri.fr/rest/content/getFile/57649f84-d7e3-44be-afa8-e12cba62e295/Poster_cryptolait_IJPmeeting+Allemagne_vf.pdf","productions":[],"taxa":[],"production-systems":[],"areas":[{"kind":"region","code":"28"}],"pests":[]}