title: Paratuberculosis in sheep: Histochemical, immunohistochemical and in situ hybridization evidence of in utero and milk transmission.
abstract: To investigate in utero and milk transmission of Mycobacterium avium subsp. paratuberculosis (MAP), tissues from thirteen pregnant sheep, naturally infected and serologically positive to MAP, were examined by means of histochemistry, immunohistochemistry and in situ hybridization. Soon after parturition, ewes were euthanized and tissues samples were collected and prepared. The offspring (18 lambs) were divided into three groups to investigate different routes of MAP transmission. Lambs were sacrificed at three months old and the tissue samples collected, formalin-fixed and paraffin embedded. Hematoxylin and eosin and Ziehl-Neelsen staining methods were performed on fixed tissues for general examination and for detection of acid-fast bacteria. Additionally, immunohistochemical and in situ hybridization techniques were used to detect MAP antigen and MAP DNA respectively. This study of a flock of MAP-infected sheep indicates both in utero and milk transmission of MAP from dams to their offspring. Importantly, this study detected the presence of MAP in the mammary gland and mammary lymph nodes of adult ewes therefore indicating a significant route for the potential exposure to humans from this bacterial infection.
authors.affiliation: Department of Animal Pathology, School of Veterinary Medicine, University of Pisa, Italy; Department of Veterinary Pathology, School of Veterinary Science, University of Liverpool, UK. Electronic address: rverin@liverpool.ac.uk.
authors.forename: Ranieri
authors.initials: R
authors.lastname: Verin
authors.affiliation: Department of Animal Pathology, School of Veterinary Medicine, University of Pisa, Italy.
authors.forename: Marco
authors.initials: M
authors.lastname: Perroni
authors.affiliation: School of Biosciences and Veterinary Medicine, University of Camerino, Italy.
authors.forename: Giacomo
authors.initials: G
authors.lastname: Rossi
authors.affiliation: Istituto Zooprofilattico Sperimentale Lazio and Toscana, Viterbo, Italy.
authors.forename: Luigi
authors.initials: L
authors.lastname: De Grossi
authors.affiliation: DVM, private pratictioner, Pisa, Italy.
authors.forename: Roberto
authors.initials: R
authors.lastname: Botta
authors.affiliation: Istituto Zooprofilattico Sperimentale Lazio and Toscana, Viterbo, Italy.
authors.forename: Bruno
authors.initials: B
authors.lastname: De Sanctis
authors.affiliation: Department of Veterinary Medicine, University of Sassari, Italy.
authors.forename: Stefano
authors.initials: S
authors.lastname: Rocca
authors.affiliation: Department of Veterinary Medicine, University of Sassari, Italy.
authors.forename: Tiziana
authors.initials: T
authors.lastname: Cubeddu
authors.affiliation: Department of Veterinary Pathology, School of Veterinary Science, University of Liverpool, UK.
authors.forename: Hayley
authors.initials: H
authors.lastname: Crosby-Durrani
authors.affiliation: Department of Animal Pathology, School of Veterinary Medicine, University of Pisa, Italy.
authors.forename: Ennio
authors.initials: E
authors.lastname: Taccini
mesh_terms: D000818:Animals; D005260:Female; D018445:Infectious Disease Transmission, Vertical / Q000662:veterinary*; D008892:Milk / Q000382:microbiology; D016927:Mycobacterium avium subsp. paratuberculosis / Q000302:isolation & purification; D010283:Paratuberculosis / Q000382:microbiology / Q000635:transmission*; D011247:Pregnancy; D011251:Pregnancy Complications, Infectious / Q000382:microbiology / Q000662:veterinary*; D012756:Sheep; D012757:Sheep Diseases / Q000382:microbiology / Q000635:transmission*; D014599:Uterus / Q000382:microbiology
keywords: Immunohistochemistry; In situ hybridization; In utero; Milk transmission; Paratuberculosis; Sheep