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BackgroundBackground
3 captive-born juvenile Maras3 captive-born juvenile Maras Unexpected death 1999-2000Unexpected death 1999-2000 Africam Safari (Puebla, Mexico)Africam Safari (Puebla, Mexico)
Intralesional protozoal cysts with myriads Intralesional protozoal cysts with myriads of crescent shaped bradyzoites in the of crescent shaped bradyzoites in the cytoplasm of host cellscytoplasm of host cells
Host cells were hypertrophied, Host cells were hypertrophied, occasionally multinucleate, surrounded by occasionally multinucleate, surrounded by a thick eosinophilic capsulea thick eosinophilic capsule
Suspected Protozoal DiseaseSuspected Protozoal Disease
Besnoitia sp.Besnoitia sp. (Family (Family SarcocystidaeSarcocystidae)) Indirect life cycleIndirect life cycle
Definitive carnivore hostDefinitive carnivore host Intermediate host Intermediate host
Horses, ruminants, opossums, rodents, rabbits, lizardsHorses, ruminants, opossums, rodents, rabbits, lizards
Case ConfirmationCase Confirmation
Gross Necropsy FindingsGross Necropsy Findings Histological findingsHistological findings Other testingOther testing
Post-mortem Post-mortem urinalysisurinalysis Lung Lung cultureculture Electron microscopy of lungElectron microscopy of lung
DiagnosisDiagnosis
Pulmonary besnoitasis (disseminated in Pulmonary besnoitasis (disseminated in Mara #3)Mara #3) By light microscopy and EM, By light microscopy and EM, BesnoitiaBesnoitia cysts cysts
can be differentiated from other tissue cyst can be differentiated from other tissue cyst forming coccidia in the family forming coccidia in the family SarcocystidaeSarcocystidae
Specifically, bradyzoites are surrounded by a Specifically, bradyzoites are surrounded by a parasitophorous vacuole within the cytoplasm of a parasitophorous vacuole within the cytoplasm of a hypertrophied and multinucleate fibroblast hypertrophied and multinucleate fibroblast surrounded by a thick capsule composed of surrounded by a thick capsule composed of collagen and electrodense capsulescollagen and electrodense capsules
Establishing Endemic LevelsEstablishing Endemic Levels
Retrospective review of all Mara necropsy Retrospective review of all Mara necropsy cases at Africam Safaricases at Africam Safari 54 Animals, 1996-200354 Animals, 1996-2003 10 more cases that had occasional or low 10 more cases that had occasional or low
numbers of similar cysts in the lungs with numbers of similar cysts in the lungs with minimal or moderate inflammation minimal or moderate inflammation surrounding themsurrounding them
Severity of these lesions correlated with the Severity of these lesions correlated with the presence of lytic and mineralized cystspresence of lytic and mineralized cysts
One Mara also had cysts in the pancreas and One Mara also had cysts in the pancreas and peripancreatic adipose tissueperipancreatic adipose tissue
Is There An outbreak?Is There An outbreak?
There was no evidence of Besnotiasis There was no evidence of Besnotiasis prior to 1999prior to 1999
All of the 13 total cases with cystsAll of the 13 total cases with cysts Present in the lungs with concurrent interstitial Present in the lungs with concurrent interstitial
or granulomatous pneumoniaor granulomatous pneumonia
Descriptive EpidemiologyDescriptive Epidemiology
Herd historyHerd history Case descriptionCase description Environmental factorsEnvironmental factors
Environmental FactorsEnvironmental Factors
DietDiet Water Water ad libitumad libitum Oranges, carrots, chopped alfalfa and rabbit pelletsOranges, carrots, chopped alfalfa and rabbit pellets
EnclosureEnclosure 120m120m22
Fenced with 1.20m high wire mesh and bamboo on one sideFenced with 1.20m high wire mesh and bamboo on one side Sandy substrateSandy substrate Often see squirrels (Often see squirrels (Spermophilus variegatusSpermophilus variegatus), Mice (), Mice (Mus Mus
musculusmusculus) and various birds inside the enclosure.) and various birds inside the enclosure. Often see opossum (Often see opossum (Didelphis virginianaDidelphis virginiana), ringtail cat ), ringtail cat
((Bassariscus astutusBassariscus astutus) and stray cats () and stray cats (Felis domesticusFelis domesticus) inside ) inside the park.the park.
1996-20031996-2003
13 positive animals in an 8 year period 13 positive animals in an 8 year period 54 total deaths54 total deaths
24%24% 3 animals from current colony of 373 animals from current colony of 37
8%8%
Background of Background of BesnotiaBesnotia
Species of Species of besnotiabesnotia have heterogeneous life have heterogeneous life cyclescycles Uses predator-prey relationships to ensure transmissionUses predator-prey relationships to ensure transmission Intermediate host becomes infected by ingesting Intermediate host becomes infected by ingesting
sporulated oocysts in feed or water contaminated with sporulated oocysts in feed or water contaminated with fecesfeces
Most Most besnoitia sppbesnoitia spp. Have a broad range of intermediate hosts. Have a broad range of intermediate hosts
Cats are definitive hosts of Cats are definitive hosts of B. darlingiB. darlingi and and B. B. wallacewallace Role of cats and carnivores in the life cycle of other Role of cats and carnivores in the life cycle of other
BesnoitiaBesnoitia species is unclear species is unclear
HypothesisHypothesis
Wild carnivores in the park?Wild carnivores in the park? Definitive hosts by fecal shedding of oocystsDefinitive hosts by fecal shedding of oocysts
Hematophagous insects?Hematophagous insects? Transmission by these insects may occur in ungulatesTransmission by these insects may occur in ungulates
Pre-existing chronic granulomatous Pre-existing chronic granulomatous inflammation?inflammation? Involved in the development of fatal interstitial Involved in the development of fatal interstitial
pneumoniapneumonia Concurrent infection with agent causing Concurrent infection with agent causing
interstitial pneumonia?interstitial pneumonia? Undetected by available diagnostic techniquesUndetected by available diagnostic techniques
Investigate HypothesisInvestigate Hypothesis
Review literature for similar casesReview literature for similar cases Environmental InvestigationEnvironmental Investigation
ReferenciasReferencias Ayroud M, Leighton F, Tessaro S: The morphology and pathology of Ayroud M, Leighton F, Tessaro S: The morphology and pathology of Besnoitia spBesnoitia sp. in reindeer . in reindeer
((Rangifer tarandus tarandusRangifer tarandus tarandus). J Wildl Dis ). J Wildl Dis 31:31:319-326, 1995319-326, 1995 Diesing L, Heydorn AO, Matuschka FR, Bauer C, Pipano E, de Waal DT, Potgieter FT: Diesing L, Heydorn AO, Matuschka FR, Bauer C, Pipano E, de Waal DT, Potgieter FT: Besnoitia Besnoitia
besnoitibesnoiti: studies on the definitive host and experimental infections in cattle. Parasitol Res : studies on the definitive host and experimental infections in cattle. Parasitol Res 75:75:114-114-117, 1998 117, 1998
Dubey JP, Greene C: Enteric coccidiosis. In: Infectious diseases of the dog and cat, ed. Greene Dubey JP, Greene C: Enteric coccidiosis. In: Infectious diseases of the dog and cat, ed. Greene C, pp. 835-846. WB Saunders Company, Philadelphia, PA,USA, 1990C, pp. 835-846. WB Saunders Company, Philadelphia, PA,USA, 1990
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Mbuthia P, Gathumbi P, Bwangamoi O, Wasike P: Natural besnoitiosis in a rabbit. Vet Parasitol Mbuthia P, Gathumbi P, Bwangamoi O, Wasike P: Natural besnoitiosis in a rabbit. Vet Parasitol 45:45:191-198, 1993191-198, 1993
Nganga CJ, Kasigazi S: Caprine besnoitiosis: studies on the experimental intermediate hosts and Nganga CJ, Kasigazi S: Caprine besnoitiosis: studies on the experimental intermediate hosts and the role of the domestic cat in transmission. Vet Parasitol the role of the domestic cat in transmission. Vet Parasitol 52:52:207-210, 1994 207-210, 1994
Venturini L, Petruccelli M, Piscopo M, Unzaga JM, Venturini MC, Bacigalupe D, Basso W, Dubey Venturini L, Petruccelli M, Piscopo M, Unzaga JM, Venturini MC, Bacigalupe D, Basso W, Dubey JP: Natural JP: Natural Besnoitia sp.Besnoitia sp. infection in domestic rabbits from Argentina. Vet Parasitol infection in domestic rabbits from Argentina. Vet Parasitol 107107:273-278, :273-278, 20022002