Tritrichomonas foetus (altgr. tri ‚drei‘, thrix ‚Haar‘, monas ‚Einheit‘ und lat. foetus ‚Nachkommenschaft‘) ist ein Einzeller, der bei Rindern die anzeigepflichtige Trichomonadenseuche – eine mit Fruchtbarkeitsstörungen und Fehlgeburten einhergehende Deckseuche – und bei Katzen die Tritrichomonose – eine Durchfallerkrankung – verursacht. Allerdings unterscheiden sich die Isolate von Katzen und Rindern genetisch, so dass eine Übertragung zwischen beiden Tierarten mittlerweile als unwahrscheinlich gilt. Erstmals wurde T. foetus bei Schweinen nachgewiesen und als T. suis bezeichnet. Bei Schweinen ist T. foetus ein harmloser Kommensale der Nasenschleimhaut und des Darmtrakts.[1]
T. foetus ist ein 10–25 µm × 3–15 µm großer, birnenförmiger Einzeller mit drei Vordergeißeln und einer hinteren Schleppgeißel. Die Schleppgeißel besteht aus einem dicken Achsenstab und einer undulierenden Membran. Der Achsenstab wirkt vorn verdickt, am Ende dornförmig und überragt das Hinterende.[2] Die Vermehrung erfolgt durch Zweiteilung.
Tritrichomonas foetus (altgr. tri ‚drei‘, thrix ‚Haar‘, monas ‚Einheit‘ und lat. foetus ‚Nachkommenschaft‘) ist ein Einzeller, der bei Rindern die anzeigepflichtige Trichomonadenseuche – eine mit Fruchtbarkeitsstörungen und Fehlgeburten einhergehende Deckseuche – und bei Katzen die Tritrichomonose – eine Durchfallerkrankung – verursacht. Allerdings unterscheiden sich die Isolate von Katzen und Rindern genetisch, so dass eine Übertragung zwischen beiden Tierarten mittlerweile als unwahrscheinlich gilt. Erstmals wurde T. foetus bei Schweinen nachgewiesen und als T. suis bezeichnet. Bei Schweinen ist T. foetus ein harmloser Kommensale der Nasenschleimhaut und des Darmtrakts.
T. foetus ist ein 10–25 µm × 3–15 µm großer, birnenförmiger Einzeller mit drei Vordergeißeln und einer hinteren Schleppgeißel. Die Schleppgeißel besteht aus einem dicken Achsenstab und einer undulierenden Membran. Der Achsenstab wirkt vorn verdickt, am Ende dornförmig und überragt das Hinterende. Die Vermehrung erfolgt durch Zweiteilung.
Tritrichomonas foetus is a species of single-celled flagellated parasites that is known to be a pathogen of the bovine reproductive tract as well as the intestinal tract of cats. In cattle, the organism is transmitted to the female vagina and uterus from the foreskin of the bull where the parasite is known to reside. It causes infertility, and, at times, has caused spontaneous abortions in the first trimester. In the last ten years, there have been reports of Tritrichomonas foetus in the feces of young cats that have diarrhea[1] and live in households with multiple cats. Tritrichomonas foetus looks similarly to Giardia and is often misdiagnosed for it when viewed under a microscope.[2]
Tritrichomonas foetus is the genus Tritrichomonas within the order Tritrichomonadida in the Kingdom Protoctista. The parasite is 5-25 µm in size and is spindle shaped with four flagella, which are whiplike projections, and an undulating or wavy membrane. Three of the flagella are found on the anterior end and approximately the same length as the body of the parasite. The fourth is on the posterior end.[3] Their movement is jerky and in a forward direction, and they also do "barrel rolls". The organisms look like small tadpoles with small tails when viewed microscopically. The parasite interacts with bacteria that normally reside in the intestinal tract by adhering to the intestinal epithelium of the host.
Bulls do not show any clinical signs of infections and can infect females at mating. In cows, there may be infertility, embryonic death and abortion, and reproductive tract infections such as pyometra.[4][5] Cows may show outward signs of infection, namely a sticky, white vaginal discharge, which may occur for up to two months after the initial infection. The disease results in abortion of the embryo, often within ten days of conception. Evidence of repeat breeding or infertility may be a sign of trichomoniasis. After the abortion of the fetus and the cow's return to a normal estrous cycle, the cow may come into estrus again, at which point it may be bred again. Eventually the cow will be able to cycle normally and carry a fetus to term. However, the irregularities after initial infection present obvious clinical signs of reproductive inconsistencies, which should be examined by a veterinarian immediately.[6] Bulls remain infected for life, but cows can successfully clear the infection, but reinfection is likely.[7]
Diagnosis can be done on both males and females; however, bulls are tested more since they remain carriers. In cattle, a presumptive diagnosis can be made from the signs of infertility and geography. Diagnosis may rely on microscopic examination of vaginal or preputial smears. Complement fixation can be performed to detect parasite antibodies in vaginal secretions.[5]
Several related trichomonads may be mistaken for Tritrichomonas foetus, including: Trichomonas vaginalis, Trichomonas gallinae, and Trichomonas tenax. A study by Richard Felleisen found that identification of T. foetus using Polymerase chain reaction (PCR) resulted in a more accurate identification. The 5.8S rRNA gene of T. foetus was found to have 12 copies in the T. foetus genome. This indicated that the organism could be identified via amplification of this gene by PCR. Not only would this allow for identification of T. foetus, but also differentiation from other trichomonad species.[6] Diagnosis can also be done using the InPouch TF from a prepuce scraping sample from a bull.
Bulls can be treated in different ways. Various imidazoles have been used, but none are both safe and effective in treatment. Ipronidazole is probably most effective but, due to its low pH, frequently causes sterile abscesses at injection sites. Bulls can also remain carriers for life and can easily be susceptible to reinfection even after successful treatment. However bulls can sometimes remain carriers for life once they become infected. Cows can be treated by being left alone for around three months to allow them time to shed the vaginal and uterine lining that is affected. Semen can also be treated successfully with dimetridazole and then used for artificial insemination. Commercially available vaccines (TrichGuard,[8] Tricovac[9]) cannot prevent infection, but confer disease attenuation and some level of protection against complications.[10][11] In a placebo-controlled trial of TrichGuard with forty prophylactically vaccinated, T. foetus-infected beef heifers, 95% of the heifers in the active treatment group conceived, as opposed to 70% in the placebo group. 50% in the TrichGuard-group gave birth to a live calf, compared to 20% in the placebo group.[12] The most effective control method for eliminating the infection in a herd or an individual remains by culling the animal(s) and replacing them with virgin animals after positive test results. Cows can remain in the herd if given enough time to shed the infection or can be culled like bulls to allow faster turnover and assure the herd is clear of the infection.[2][3]
There are two routes of direct transmission for Tritrichomonas foetus between cattle: cow-to-bull or bull-to-cow. The most common route of transmission is from bull to cow. The cow can get infected either when naturally bred to an infected bull or when receiving semen from an infected bull during artificial insemination. However, in the case of artificial insemination, while T. foetus is capable of surviving the process used to freeze semen after collection, it is usually killed by drying or high temperatures. In cow-to-bull transmission, a female that has already been infected with T. foetus is bred with a male, who then contracts the infection.[13]
Tritrichomonas foetus in cattle is often attributed to direct transmission via reproduction with an infected individual; however, studies have documented evidence of T. foetus persisting in the intestinal tract of the housefly, suggesting a possible mode of transmission outside of reproduction.[14] Tests performed on feline T. foetus have also shown its persistence in room temperature, humid environments for up to ten days.[15]
The prognosis for cattle is not good. Infected bulls are advised to be culled; cows should also be culled due to easy reinfection even after clearing the initial infection. Trichomoniasis is a reportable disease in cattle, and as of now, there is no effect treatment. Prevention and smart farm practices are the only remedy. Testing should be done on any bull prior to exposing it to the herd. Limiting exposure of the herd to other cattle and limiting the introduction of open cows into the herd are good preventative practices. An estimated 42% of cows will acquire the disease if bred to an infected bull.[16]
In cats, Tritrichomonas foetus is characterized by diarrhea that comes and goes and may contain blood and mucus at times. The diarrhea is semi formed in a cow pie consistency. In most cases it affects cats of 12 months of age or younger and cats from rescue shelters and homes with multiple cats. Close and direct contact appears to be the mode in which the parasite is transmitted. Tritrichomonas foetus is most common in purebred felines, breeds like Bengals, Persians, etc. Since catteries tend to trade queens and studs to provide greater genetic diversity, the parasite can be spread from one cattery to another.
Doctor Jody L. Gookin and her colleagues identified Tritrichomonas foetus, which causes diarrhea in domestic cats. As a result of her research people are able to diagnose, and a treat the infection.[17]
However, just because the cat doesn't show signs of diarrhea, it still could possibly be infected. Adult cats are less likely to develop diarrhea when infected, but they will still serve as a source of infection for other cats. Clinical signs can show up anywhere from days to years after exposure.[18]
In cats, Tritrichomonas foetus can be detected by the following four methods:
One treatment that has been effective in experimentally infected cats is ronidazole but this remains an unapproved use.
The primary transmission route is the litter box that is shared by both infected and uninfected cats, where a well-timed use by two cats can transfer the parasite from the feces of one cat to the paws of another where they later become ingested during the act of grooming. In cats, Tritrichomonas foetus is able to live several days in wet stool. Mutual grooming may also transfer the parasite. There is no evidence that T. foetus is sexually transmitted or infects the reproductive tract or mammary glands of cats.[18]
The long term prognosis for cats with TF is generally good, the diarrhoea will usually resolve itself in untreated cats. However this can take many months, and cats which no longer show clinical signs can continue to shed the organism for up to two years.[19] It appears that over time the parasite dies off and the infection is remedied on its own. In some cases, the symptoms may improve over time, but the animal is likely to still be a carrier of the parasite, capable of transmitting it to another cat.
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Tritrichomonas foetus Tritrichomonas foetus is a species of single-celled flagellated parasites that is known to be a pathogen of the bovine reproductive tract as well as the intestinal tract of cats. In cattle, the organism is transmitted to the female vagina and uterus from the foreskin of the bull where the parasite is known to reside. It causes infertility, and, at times, has caused spontaneous abortions in the first trimester. In the last ten years, there have been reports of Tritrichomonas foetus in the feces of young cats that have diarrhea and live in households with multiple cats. Tritrichomonas foetus looks similarly to Giardia and is often misdiagnosed for it when viewed under a microscope.
Tritrichomonas foetus es un protista flagelado parásito del grupo Parabasalia. Es parásito del aparato reproductor afectando a bovinos, suinos y equinos, siendo solo patógeno en bovinos. También afecta al tracto digestivo en gatos, produciéndoles diarrea.[1] [2] [3]
Es un organismo piriforme, con un tamaño de 9 a 18 μm x 4 a 8 μm, aunque con variaciones según las condiciones fisiológicas. Es uninucleado, posee tres flagelos anteriores y uno posterior, que recorre todo el cuerpo fijado a una membrana ondulante que forma de 2 a 5 ondas, unida al resto de la célula por una fibrilla rígida llamada costa. El axostilo es una estructura microtubular que se curva alrededor del núcleo y atraviesa longitudinalmente al protista emergiendo en la zona caudal. Actúa como un eje rígido que sustenta a la célula. Posee una fibrilla parabasal, y sobre ella un cuerpo parabasal, que resulta ser el aparato de Golgi. Estos protistas son amitocondriales, obtienen su energía a través de hidrogenosomas dispersos en el citoplasma.
la reproducción de T. foetus es por fisión binaria longitudinal. En condiciones naturales el parásito se transmite de macho a hembra o viceversa por contacto sexual.La infección vaginal se establece rápidamente pudiendo encontrarse trichomonas en las secreciones vaginales entre los 10 y 35 días y a veces incluso después de la infección.
T. foetus es el agente responsable de la trichomoniasis bovina. La infección afecta a la zona genital de bovinos de ambos sexos. En el macho se produce multiplicación en la cavidad prepucial, los vasos deferentes y el epidídimo. Permanecen asintomáticos, máxime con signos de dolor al orinar y descargas purulentas que desaparecen rápidamente. Suele afectar a toros adultos y viejos. La infección permanece durante toda la vida, convirtiéndose en portadores sanos. En la hembra la infección se extiende por vagina, útero y feto. Provoca vaginitis, endometritis y abortos que algunas veces terminan en piómetras. La endometritis puede generar infertilidad definitiva en la vaca, aunque lo habitual es que las hembras superen la infección y queden gestantes de nuevo. Es frecuente la pérdida del embrión en los estadios tempranos de la gestación, lo que difícilmente se percibe como un aborto en ganadería extensiva que no realice diagnósticos de gestación. Los signos de la enfermedad en la granja aparecen al detectarse un aumento del intervalo parto-gestación. También se pueden detectar celos irregulares y vacas que repiten el celo más allá de los 22-23 días.
En gatos T. foetus es parásito intestinal y no se ha encontrado multiplicación en el aparato reproductor. Su sintomatología varía dependiendo del gato, su edad y su estado inmunológico. Así en gatos jóvenes puede causar procesos diarreicos incontrolados y constantes a lo largo del tiempo, mientras que la mayoría de adultos parasitados son asintomáticos.
Es un factor bastante importante en el comercio de gatos como mascotas, pudiendo causar pérdidas económicas en el sector. La infección se transmite por el contacto con heces diarreicas. El origen del parasitismo en gatos es desconocido, la infección puede provenir de bovinos y haber pasado a gatos, o puede haber sido un parasitismo propio de estos que no había sido detectado antes.
Los casos de infección por T. foetus en humanos no son comunes, no obstante se han encontrado algunos casos: En 1998 un paciente trasplantado de medula ósea murió de meningitis, tras realizar la autopsia se encontró T. foetus en tejido encefálico. En 2007 un paciente de 52 años, que vivía en una granja, murió de peritonitis causada por T. foetus. El paciente era un hombre inmunodeprimido, que padecía artritis reumatoide, cirrosis hepática y había sido esplenectomizado. Un caso similar tuvo lugar en 2011, el paciente también era granjero y había sufrido esplenectomía. T. foetus también se ha encontrado en pacientes que fallecieron a causa de una neumonía. Es desconocido si en estos casos T. foetus es la principal causa de muerte o simplemente su presencia se debe a un comportamiento oportunista.
T. foetus puede sintetizar un amplio juego tanto de exo- como de endoenzimas. Entre las más importantes encontramos:
El diagnóstico de la trichomonosis bovina debe hacerse poniendo en evidencia la infección por T.foetus. El procedimiento más común es la identificación del parásito al microscopio óptico, a partir de muestras biológicas de bóvidos infectados, o a partir de cultivos. T. foetus puede aislarse de mucus cérvico vaginal, de pulmón y del contenido gastrointestinal de fetos abortados, placenta y fluidos prepuciales. Los cultivos se deben inocular en medio adecuado a 37°C, y examinarse diariamente durante 7 días. Si las muestras van a permanecer más de 6-8 horas sin inocularse tras la obtención, han de conservarse en caliente. Para realizar un diagnóstico correcto por microscopia óptica hay que basarse en la morfología característica del parásito. La PCR (reacción en cadena de la polimerasa) pone de manifiesto la presencia del parásito con gran precisión y exactitud incluso cuando éste no es ya viable. Kits de diagnóstico basados en inmunohistoquímica también permiten detectar la presencia del parásito.
Datos: Q7844461
Tritrichomonas foetus es un protista flagelado parásito del grupo Parabasalia. Es parásito del aparato reproductor afectando a bovinos, suinos y equinos, siendo solo patógeno en bovinos. También afecta al tracto digestivo en gatos, produciéndoles diarrea.
Trichomonas foetus è un protozoo multiflagellato trasmesso per via venerea e parassita dell'apparato riproduttore dei bovini, causando la trichomoniasi bovina. Nei tori l'infezione è asintomatica, nelle vacche gravide causa riassorbimento embrionale e aborto nei primi quattro mesi di gravidanza, spesso confuso con problemi di infertilità. È cosmopolita.
È piriforme di dimensioni 20x10 µm, dotato di nucleo e di quattro flagelli di cui tre liberi e uno fisso. All'interno del protozoo si trova una struttura bastoncellare rigida, axostilo, che si estende lungo l'asse antero-posteriore della cellula.
I tori mantengono la malattia per tutta la vita e la trasmettono con l'accoppiamento. Nella femmina i parassiti raggiungono l'utero provocando endometriti, solitamente tornano in vagina poco prima dell'estro. I parassiti si trovano nel liquido amniotico e allantoideo. Può capitare che la vacca guarisca spontaneamente e ne rimanga poi immune per tutta la vita.
Trichomonas foetus è un protozoo multiflagellato trasmesso per via venerea e parassita dell'apparato riproduttore dei bovini, causando la trichomoniasi bovina. Nei tori l'infezione è asintomatica, nelle vacche gravide causa riassorbimento embrionale e aborto nei primi quattro mesi di gravidanza, spesso confuso con problemi di infertilità. È cosmopolita.
È piriforme di dimensioni 20x10 µm, dotato di nucleo e di quattro flagelli di cui tre liberi e uno fisso. All'interno del protozoo si trova una struttura bastoncellare rigida, axostilo, che si estende lungo l'asse antero-posteriore della cellula.
Tritrichomonas foetus é uma espécie de protozoário flagelado piriforme, unicelular, conhecido por ser um patógeno do trato reprodutivo bovino, bem como do trato intestinal de gatos. No gado, o organismo é transmitido para a vagina e útero feminino a partir do prepúcio do touro, onde o parasita é conhecido por residir. Causa infertilidade e, às vezes, provoca abortos espontâneos no primeiro trimestre. Nos últimos dez anos, tem havido relatos de Tritrichomonas foetus nas fezes de gatos jovens que têm diarreia[1] e vivem em domicílios com vários gatos.
Se aloja no trato genital tanto masculino quanto feminino e é transmitido pela cópula ou por inseminação artificial mal conduzida (quando o sêmen pode estar contaminado, quando não se sabe a procedência do sêmen, por utilização de instrumentação não esterilizada ou mal esterilizada, etc.).
Em machos, o parasita se aloja principalmente na cavidade prepucial. Pode não haver sintomatologia evidente como pode causar dor ao urinar (nesse caso o animal urina parceladamente) e epididimite. Como se trata de sintomas pouco perceptíveis clinicamente, o macho infectado é o principal disseminador da infecção.
Em fêmeas, pode haver vaginite com secreção purulenta, febre alta e metrite caso o parasita ascenda ao útero. Em vacas prenhas, a ascensão ao útero pode causar tanto metrite quanto infecção de placenta e causar aborto. Quando infectadas antes de ficarem prenhas, em cerca de 2 a 6 semanas após a concepção o feto é abortado. Há casos em que o feto é "macerado" no útero. Simplesmente o feto morre e não é eliminado. A própria secreção elimina os parasitas em grande quantidade e em cerca de 3 meses sem cópula pode haver a cura espontânea.
Tritrichomonas foetus é uma espécie de protozoário flagelado piriforme, unicelular, conhecido por ser um patógeno do trato reprodutivo bovino, bem como do trato intestinal de gatos. No gado, o organismo é transmitido para a vagina e útero feminino a partir do prepúcio do touro, onde o parasita é conhecido por residir. Causa infertilidade e, às vezes, provoca abortos espontâneos no primeiro trimestre. Nos últimos dez anos, tem havido relatos de Tritrichomonas foetus nas fezes de gatos jovens que têm diarreia e vivem em domicílios com vários gatos.
