[Respiratory affections of swine. Remarks made in the Loire region [France]]

atrophic rhinitis cerdo farm management gestion de l'exploitation agricole gestione aziendale manejo de fincas pays de la loire piggeries pneumonia pneumonie pocilga polmonite porcherie porcilaie porcin rhinite atrophique rinite atrofica sintomi swine symptome symptoms vaccination vaccinazione ventilation ventilazione