Tritrichomonas foetus (1)

Question 1

How do you identify?

Answer 1

Pear-shaped

10-25 x 3-15 micro m

Single nucleus

3 anterior flagella
- Arising from basal body situated at anterior rounded end

1 posterior flagellum

Axostyle, undulating membrane

Question 2

Explain the life cycle in cattle

Answer 2

Genital tracts of cattle

 - Uterus, cervix, and sometimes vagina of cow
 - Prepuce of bulls

Transmitted by coitus

After abortion, can be found in amniotic and allantoic fluids and stomach contents of foetus

Inhabits prepuce
- Transmission to cows via coitus

From vagina trichomonads reach uterus via cervix

Trichomonads flushed from uterus to vagina (2-3 days before estrus)
- Bull infected by servicing cows

No cystic stage

Question 3

What are the sites of infection in cows?

Answer 3

Uterus

Cervix

Vagina

Question 4

What is the site of infection in Bulls?

Answer 4

Prepuce

Question 5

Describe the Pathogenesis in Bulls

Answer 5

Preputial discharge associated with small nodules on the preputial/penile membranes may develop shortly after infections, no other clinical signs

Question 6

Describe the Pathogenesis in cows

Answer 6

Low grade endometritis (sometimes purulent endometritis occurs) -
effects implantation in uterus

Abortion before 4th month of pregnancy common
- Often undetected because fetus is small

Result in decreased herd yield

 - Repeated returns to service
 - Irregular estrus cycles

Self-cure - develop immunity (not long lasting)

Question 7

Describe the general trichomonosis in cattle

Answer 7

A venereal disease

Causes infertility, open cows, and occasional abortions in cows and heifers

Can be economically devastating and costly to eradicate from a herd

Question 8

Describe the trichomonosis in Bulls

Answer 8

Organisms survive in microscopic folds of skin that line the bull’s penis and internal sheath

Asymptomatic lifetime carrier: semen quality and sexual behavior
appear normal

As bull ages, the skin grows, folds increase in the penis and sheath, creating additional places for the organism to thrive

Older Bulls (over 3 years) more likely to become chronically infected than younger Bulls (6.7% vs. 2.0% prevalence in CA)

Question 9

Describe the trichomonosis in cows

Answer 9

The organism lives in the vagina, cervix, and uterus
- Short lived until her immune system eventually destroys it

A cow or heifer can become repeatedly infected

Cow does not appear ill

Cow may show a subtle, mild, vaginal discharge in 1-3 weeks (pyometra)

An inflammatory response leading to abortions

Repeated breedings

Wide ranges of gestational ages at pregnancy checks

Question 10

What are the clinical signs in cattle?

Answer 10

In bull - none

In cows

 - Early abortions
 - Repeated returns to service
 - Decreased herd yield (8-29%)

Question 11

How do you diagnose?

Answer 11

Identification of organisms in samples from preputial scrapings/washings from bull
- Scraping with long pipette replaced washing method

Vaginal/cervical secretions from cow can be tested

PCR

 - Gel PCR
 - Quantitative PCR
 - Differentiate contaminate trichomonads
 - Detect dead cells

Culture

 - In-Pouch TF Test - convenient
        - Easy
        - Suited for trichomonad growth
        - Direct microscopic examination 
 - Slow (days)
 - Detect live cells only
 - Diamonds Media - some labs prefer

Diagnosis is on herd basis

Question 12

Explain diagnosis on herd basis

Answer 12

The Bulls go back to work at the end of a long breeding season

A lot of open cows at the end of a short breeding season

A 10-40% reduction in pregnant cows at pregnancy check time

A spread out calving season

Question 13

Describe herd based diagnosis in Bulls

Answer 13

Best to test after2 weeks of sexual rest

Usually culture for up to 7 days

If even one bull is positive, you have to assume that the herd has been exposed

Three consecutive tests recommended for Bulls, once a week for 3 consecutive weeks

 - 1st: ~80-90% sensitivity
 - 2nd: ~ 96-99% sensitivity
 - 3rd: >99% sensitivity

Question 14

Describe herd based diagnosis in cows

Answer 14

Usually clear infection rapidly - often in one season

Test soon after embryo death

Months delay for suggestive history in a herd

Question 15

How do you prevent in cattle?

Answer 15

Prevention is key

REPORTABLE disease

Control - an integrated approach

 - All Bulls tested - positive Bulls culled
        - Young bulls (4 years old
 - Infected for life - Cull

AI from uninfected donor only satisfactory control
- Transmission can occur by insemination instruments/by
gynecological examination

Appropriate hygiene techniques

Question 16

Explain the life cycle in cats

Answer 16

Colonize distal ileum/colon

Trophozoites reproduce by binary fission (mucus or large intestine)

Cannot survive long
- Up to 3 days in moist feces in environment after being discharged

Transmission via fecal-oral route via shared litter boxes

Question 17

What is the site of infection in cats?

Answer 17

Large intestine

Question 18

What are the clinical signs in cats?

Answer 18

Chronic waxing/waning, malodorous large bowel diarrhea

 - Often with blood
 - Mucus
 - Some staining

Appear to have a normal appetite

Pure breeds/young animals

Question 19

Describe feline trichomonosis

Answer 19

All breeds susceptible

~ 1/3 purebred feline population may be infected

T. foetus lives for at least a day in wet stools

The primary infection is probably by the fecal-oral route

Infected cats may be asymptomatic

Symptomatic cats show diarrhea - cow pie like that are often gassy
and malodorous

Question 20

What are the risk factors in cats?

Answer 20

Age - one year old or younger

Breed - purebred

History of diarrhea

Co infection with other enteric Protozoa

Question 21

How do you diagnose in cats?

Answer 21

Identification in fecal samples by direct smear or culture

Direct smear - low sensitivity

Fecal culturing - BioMed’s Feline InPouch TF (

Question 22

How do you treat in cats?

Answer 22

Ronidazole - 30 mg/kg oral for 14 days

Question 23

What are the hosts?

Answer 23

Cattle

Cats