SheepSheep DiseasesSheep, DomesticMedical History TakingSheep, BighornHistory, 20th CenturyHistory, 19th CenturyHistory of MedicineJaagsiekte sheep retrovirusHistory, 17th CenturyGoatsHistory, 18th CenturyHistory, AncientHistoryScrapieHistory, 21st CenturyHistory, MedievalRisk FactorsHistory, 16th CenturyPregnancyGoat DiseasesHistory, 15th CenturyPhylogenyPulmonary Adenomatosis, OvineWoolTime FactorsFetusNatural HistoryRumenFamily HealthCattleCase-Control StudiesPrevalencePlant PoisoningLymphGenetic VariationSpecies SpecificityEvolution, MolecularHistory of NursingAge FactorsErythrocytesReproductive HistoryProspective StudiesOmasumFollow-Up StudiesRetrospective StudiesBiological EvolutionStomach, RuminantPrionsCohort StudiesFoot RotPrPSc ProteinsQuestionnairesMolecular Sequence DataGenotype