Brucella spp. Flashcards
Structure
Cocci or short rod, gram-negative, non-motile bacteria
Family
Fastidious aerobes
Fastidious aerobes
require special conditions and substances for their growth
B. abortus
cattle, bison, elk, Asian buffalo
B. suis
swine, cattle, caribou, reindeer, european hare, rodents
B. canis
domestic dogs, coyotes, foxes
B. ceti
cetaceans
B. pinnipedialis
pinnipeds
Zoonotic types
B. abortus, B. suis, B. canis, and B pinnipedialis
Which strand is most widespread
B. abortus
Main reservoirs
wild ungulates and domestic species
Transmission methods
ingestion, inhalation, and direct contact through skin abrasions and mucous membranes
shed in milk, urine, or semen
B. abortus main transmission method
licking and ingestion of fetal membranes or aborted fetus, and of uterine discharge
Is chronic infection possible
yes, found in aborted fetuses and full-term offspring, can have reinvasion after birth
Pathogenesis
one in body-> replicates in vacoules in macrophages, dendritic celled, and placental trophoblasts
crosses mucous membrane->phagocytized-> disseminates to to urogenital and lymphoid tissues -> come resistance to bactericidal properties-> replication
Pathogenesis phases
Incubation
Acute
Chronic
Acute
invades and disseminates into host’s tissue
chronic
severe organ damage and death of host organism
Incubation
2-4 weeks
Abortion rate
30-80%
Clinical signs
abortions, stillbirths, weak offspring at birth, decreased lactation, orchitis, infertility, inflammation of joints
Clinical signs in marine animal
neurological
disorientation, ataxia, tremors, seizures
Pathologic Lesions in fetuses
serohemorrhagic fluid in body cavities, fibrinous plueritis, splenomegaly, hepatomegaly, lymphadenomegaly, in the placenta is edematous and placentomes have necrosis and or hemorrhage
Pathologic lesions male reproductive tract
abscesses, inflammatory lesions, atrophy
Pathologic lesions female reproductive tract
uterine nodules, abscesses, fibrinous necrotic, exudate, and hemorrhage
Pathologic lesions
lymph nodes, liver, spleen, mammary glands, joints, tendon sheaths and bones have granulomatous inflammation
hygromas, cloudy CSF, hyperemia of meninges
Diagnostics
Serological tests: bison need multiple for confirmation
PCR, MALDI-TOF
Histopath slides with Ziehl-Neelsen stain
Bacterial isolation using cultures
ELISA, serum agglutination test
Treatment
antibiotics, culling infected animals
Management
REPORTABLE DISEASE
-avoid putting new herds in contaminated environments
-vaccination of domestic species
-treatment of sick animals
-decontamination of farming lands
Bison Management Plan
-national park service prevents bison from leaving park during periods when they could come in contact with susceptible cattle
-allow some negative bison to move off park onto areas used by cattle during winter
-untested bison will be allowed in areas overlapping with cattle-> must be back in park before cattle released into area
