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[[Tritrichomonas]] foetus is a notifiable disease to the World Organisation of Animal Health ([http://www.oie.int/ OIE]).
[[Tritrichomonas]] foetus is a notifiable disease to the World Organisation of Animal Health ([http://www.oie.int/ OIE]).
Trichomonosis is not considered zoonotic at present.
Trichomonosis is not considered zoonotic at present.
=Signalment and Distribution=
=Signalment and Distribution=
Trichomonosis is presumed to exist worldwide and shows no known breed predilection among cattle. Disease is most common among extensively grazing systems and is only present in herds using natural service.
Trichomonosis is presumed to exist worldwide and shows no known breed predilection among cattle. Disease is most common among extensively grazing systems and is only present in herds using natural service.
T foetus is extremely rare in exclusively artificially inseminated units, but will survive both freezing to -196⁰C and antibiotics used in semen extenders, so proper hygiene and extensive testing of donor bulls is imperative.
T foetus is extremely rare in exclusively artificially inseminated units, but will survive both freezing to -196⁰C and antibiotics used in semen extenders, so proper hygiene and extensive testing of donor bulls is imperative.
Bull age is the most important risk factor for infection with infection much more likely in animals over 3 years old. This is due to the maturation of the crypts in the epithelium of the reproductive tract which the protozoa resides in in carrier animals. Older bulls are often chronic carriers for the remainder of their lives. Young bulls are much more likely to spontaneously clear infection and thus trophozoites are short-lived.
Bull age is the most important risk factor for infection with infection much more likely in animals over 3 years old. This is due to the maturation of the crypts in the epithelium of the reproductive tract which the protozoa resides in in carrier animals. Older bulls are often chronic carriers for the remainder of their lives. Young bulls are much more likely to spontaneously clear infection and thus trophozoites are short-lived.
No vectors are known to be involved in transmission of T foetus.
=Clinical Signs=
=Clinical Signs=
Bulls carry the infection asymptomatically. This provides a continuous source of infection which is transmitted during mating and direct contact.
Bulls carry the infection asymptomatically. This provides a continuous source of infection which is transmitted during mating and direct contact.
Transmission to females during mating is highly efficient and most will become infected after mating with an infected bull.
Transmission to females during mating is highly efficient and most will become infected after mating with an infected bull.
In females, early embryonic death by resorption and/or mummification between 21 and 100d gestation are the hallmarks of disease. Temporary or prolonged infertility is sometimes seen after abortion. The organism resides in the [[Uterus - Anatomy & Physiology|uterus]] and [[Vagina and Vestibule - Anatomy & Physiology|vagina]].
Occasionally, post-coital pyometra may be seen, presenting as a vaginal discharge or flocculated uterine fluid on a routine fertility examination
Occasionally, post-coital pyometra may be seen, presenting as a vaginal discharge or flocculated uterine fluid on a routine fertility examination
Infection is usually transient, lasting 8-18 weeks<ref><Skirrow, S.Z., BonDurant, R.H. (1990)’’’Induced Tritrichomonas foetus infection in beef heifers.’’’ J Am Vet Med Assoc, 196(6):885-889; 25<\ref>
Infection is usually transient, lasting 8-18 weeks<ref><Skirrow, S.Z., BonDurant, R.H. (1990)’’’Induced Tritrichomonas foetus infection in beef heifers.’’’ J Am Vet Med Assoc, 196(6):885-889; 25<\ref>
Less than 0.1% cows will become carriers <ref>Skirrow S. (1987)’’’ Identification of trichomonad-carrier cows’’’. J Am Vet Med Assoc, 191(5):553-554; 6<\ref>
Less than 0.1% cows will become carriers <ref>Skirrow S. (1987)’’’ Identification of trichomonad-carrier cows’’’. J Am Vet Med Assoc, 191(5):553-554; 6<\ref>
=Diagnosis=
=Diagnosis=
A presumptive diagnosis is often made in high risk geographical areas where herd fertility performance is impaired.
A presumptive diagnosis is often made in high risk geographical areas where herd fertility performance is impaired.
Immunohistochemistry may revel soluble antigen (SGA) within the epithelial cells, which is originally shed from the surface of T foetus.
Immunohistochemistry may revel soluble antigen (SGA) within the epithelial cells, which is originally shed from the surface of T foetus.
Parasite IgG and IgA can be found in vaginal secretions andserum complement fixation assays performed.
Parasite IgG and IgA can be found in vaginal secretions andserum complement fixation assays performed.
=Treatment=
=Treatment=
Only bulls are usually treated.
Only bulls are usually treated.
Treatments of choice which are proven to be effective in –vivo are acriflavine ointment applied topically to the glans penis, shaft and prepuce and nitromidazole compound given orally or topically in solution.
Treatments of choice which are proven to be effective in –vivo are acriflavine ointment applied topically to the glans penis, shaft and prepuce and nitromidazole compound given orally or topically in solution.
Note that nitrimadazoles are illegal in food animals in some countries and that precautios should be taken when applying acriflavine due to its staining and irritant nature.
Note that nitrimadazoles are illegal in food animals in some countries and that precautions should be taken when applying acriflavine due to its staining and irritant nature.
=Control=
=Control=
Testing and culling of bulls is imperative to eradication of [[Tritrichomonas]] foetus.
Testing and culling of bulls is imperative to eradication of [[Tritrichomonas]] foetus.
Cows can also be vaccinated, using two subcutaneous injections 2-4 weeks apart. The course should finish 4 weeks prior to breeding. Vaccine is safe in pregnant cattle and can be used after exposure to reduce shedding.
Cows can also be vaccinated, using two subcutaneous injections 2-4 weeks apart. The course should finish 4 weeks prior to breeding. Vaccine is safe in pregnant cattle and can be used after exposure to reduce shedding.
Implementation of artificial insemination where possible should replace natural service on infected farms.
Implementation of artificial insemination where possible should replace natural service on infected farms.
=References=
=References=
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