155. Brucellosis of sheep and goats caused by Brucella melitensis, canine brucellosis.

Question 1

Brucellosis of sheep and goats caused by B.melitensis?

Answer 1

BRUCELLOSIS OF SHEEP AND GOATS CAUSED BY B. MELITENSIS

• Chronic, asymptomatic, newly infected flock causes abortion storm

OCCURRENCE, ETIOLOGY AND EPIDEMIOLOGY

• Common in Mediterranean littoral ʹ Middle east, central asia, around arabian gulf, some countries in central
• America, Africa, india
• Free: Northern and Central Europe, North America, South-east asia, Australia, New Zealand
• Caused by B. melitensis (3 biotypes)
• Main preferred hosts are goat and sheep
• Infection: P.O. (milk) or sexually transmitted (semen, vaginal discharge)

Question 2

Pathogenesis , Clinical signs and Pathology of B. Melitensis?

Answer 2

PATHOGENESIS

• As in cattle, spontaneous regeneration is common
• Infection of a kid: till reach the age of reproduction, can heal

CLINICAL SIGNS AND PATHOLOGY

• No clinical signs, abortion (sporadic), palpable inflammatory nodules in the udder
• Sometimes orchitis and epididiymitis
• Chronic infection ʹ reproduction characteristics decrease with 30-40%

Question 3

Diagnosis of B.melitensis?

Answer 3

DIAGNOSIS

• Epidemiological data and clinical signs
• Isolation of the causative agent from fetus, fetal membranes and milk
• Serology ʹ Slide agglutination (Rose-Bengal test), CFT, ELISA,
• Intradermal brucellin test ʹ 0.1 ml, lower eyelid, 48h, 2mm ʹ used for surveillance of unvaccinated flocks
• and herds

Question 4

Treatment and prevention of B.melitensis?

Answer 4

TREATMENT AND PREVENTION

• Support the self-limiting nature of the disease : closed flock or herd
• Vaccination: modified live vaccine (Rev. 1 strain)
• Kids and lamb s.c. or conjunctival route, up to 6 months of age
• protection for years
• Not in pregnant
• ABORTION!
• Separation and rearing of weaned kids or lambs of animals which were vaccinated for years ʹ a
• brucellosis free flock can be established
• Aim: maintain disease free status!

Question 5

Canine Brucellosis

Occurence ethiology and epideemiology?

Answer 5

CANINE BRUCELLOSIS

OCCURRENCE, ETIOLOGY AND EPIDEMIOLOGY

• Worldwide (America, Asia, Africa), sporadic in Europe, New Zealand and Australia are free
• Caused by B. canis, but can also colonize and shed B. melitensis, B. abortus & B. suis
• Host spectrum is narrow: dogs and members of wild Canidae : ZOONOSIS
• Infection via oronasal contact, through mucous membranes (oral cavity, vagina, conjunctiva)
• Infective dose ʹ P.O. 106 CFU, Conjunctiva 104
• 105 CFU
• Shedding
• Bitch: vaginal discharge (estrus and mating), fetus & fetal fluid (1010 CFU/ml) for 6 wks after abortion
• Male: Settle down in prostate and epididymis ʹ semen & urine (103-106 CFU/ml) for 2 years

Question 6

Clinical signs of canine brucellosis?

Answer 6

CLINICAL SIGNS

• No characteristic clinical signs, frequently asymptomatic, enlargement of lymph nodes
• Pregnant bitches
• Abortion (btw. 45-60 days), reproduction failures (decreased Fertility), reduced litter size, increased
• neonatal mortality
• Most that have aborted have subsequent normal gestations
• Males: infertility, epididymitis, orchitis, prostatitis, scrotal dermatitis (saliva!)
• Chronic infection , aspermic, rare , disco spondylitis (lameness, paresis, paralysis), uveitis

Question 7

Diagnosis of canine brucellosis?

Answer 7

DIAGNOSIS

• Examination of semen: p.i. 5 weeks, inflammatory cells, morphological alteration of sperm
• Isolation of B. canis: vaginal discharge, fetus, fetal membranes; from blood p.i. 2-4 weeks : for years (5.5)
• Serological examination: slide agglutination, tube agglutination, AGID, IF, ELISA
• Earliest positive result: 3-12 weeks p.i.

Question 8

Treatment of canine brucellosis?

Answer 8

TREATMENT

• Fate of infected animal : removal from kennel and breeding programs, castration and treatment with antibiotics
• reduce the risk of transmission
• Combination of tetracyclines (minocycline) and aminoglycoside (streptomycin) for at least 4 weeks
• Extermination of infected animals ʹ health risk for the owner (ZOONOSIS!)

Question 9

Prevention of Canine brucellosis?

Answer 9

PREVENTION

• Serological examination
• In breeding dogs every 6 months and 3-4 weeks before mating
• When a new dog is introduced into a kennel ʹ two times in 1 month interval
• If a dog leaves the kennel ʹ before readmission
• Do not get dogs from a kennel where reproductive problems occur!
• No vaccine is available ʹ aim is seronegativity!