Trichomonosis in birds their prevention and control

Alok Kumar Singh^1#, Deepali Tiwari², Snigdha Shrivastava^3, Rupam Sachan⁴ and Pradeep Kumar⁵

¹Department of Veterinary Parasitology, College of Veterinary Science & A.H., Rewa

²B.V. Sc & A.H., Student, College of Veterinary Science & A.H., Rewa

³Department of Veterinary Medicine, COVSc & A.H., Rewa

⁴PhD Scholar, Department of Veterinary Parasitology, NDVSU, Jabalpur

⁵Department of Veterinary Parasitology, DUVASU, Mathura

^#corresponding author- email: alok122@gmail.com

Occurrence

Though other dove and pigeon species are also important hosts and can be spread by migrating birds, such as wood pigeons, turtle doves, and stock doves, the rock pigeon is believed to be the primary driver of this parasite’s global expansion. This protozoan has caused high-mortality events for wild bird populations also. There have been numerous reports of pigeons dying while consuming grain at bird feeders and grain feeders.  It has been demonstrated that T. gallinae can survive in damp or moist conditions, such as water (several hours) or moist grain (5 days). Bird feeders and baths can spread the disease. A trophozoite is the infectious stage that is directly transferred from one bird to another. According to reports, T. gallinae is most common in the late spring, summer, and fall. Through crop milk, the parasite can be transferred from parent to child. During courtship actions, pigeons can also exchange it. The parasite is acquired by raptors from their prey. The parasite is contracted by turkeys and chickens by the consumption of contaminated feed or water from infected pigeons.

Etiology

Bird infections caused by Trichomonas species are referred to as trichomonosis, “frounce” in raptors, and “canker” in doves and pigeons. Trichomonas gallinae is typically the cause of avian trichomoniasis. Other important species of the protozoan, such as Trichomonas gypaetinii in raptors and Trichomonas stableri in Pacific coast band-tailed pigeons (Patagioenas fasciata monilis), have been suggested recently. These two organisms are genetically identical to the human-normally-infecting Trichomonas vaginalis. Trichomonas species are detected in the feces of both wild and captive reptiles and are thought to be a typical element of the flora.

Resistance to physical and chemical action

Temperature: Under laboratory circumstances, it may grow in nutrient broth at 32–40°C (37°C is ideal). pH: Vulnerable to a pH below 6.5 10% bleach solutions inactivate chemicals and disinfectants. Although T. gallinae lacks an environmentally resistant cyst stage, it has been demonstrated to endure in damp or moist conditions, such as moist grain (up to five days) or water (several hours). However, it does not live outside of its host for prolonged periods of time. It is believed that the pseudocyst stage, which was just reported, shields it from adverse environmental circumstances.

Hosts

The different host such as Columbiformes Band-tailed pigeon (Patagioenas fasciata), Domestic chickens (Gallus gallus), turkeys (Meleagris gallopavo) and Peregrine falcon (Falco peregrinus) etc. are the important host.

Transmission

● By ingestion of contaminated water and feed

● Contact with infected birds to susceptible bird.

Sources

● Infectious hosts and their secretions/excretions i.e. saliva, mucus, faeces, crop and gastrointestinal contents.

• Contaminated water and feed, including infectious prey/carrion (gastrointestinal and crop contents) etc. play an important role transmit the disease.

Diagnosis

Little is known about pathogenicity of T. gallinae. If a virulent strain is contracted, death may happen as soon as 4 days after infection or as late as 3 weeks. The protozoan comes in a variety of strains. Notable virulent strains include the Mirza strain, which causes oropharyngeal lesions, and the Jones’-Barn and Eiberg strains, which infect the liver.

Clinical diagnosis

Clinical symptoms, microscopic analysis of the protozoan, and necropsy are used to make the diagnosis in avian species. The organism has four anterior flagella, an axostyle, an undulating membrane, and an oval to pyriform shape. Its length ranges from 7 to 11 μm. An infection with this protozoan can cause a variety of lesions and clinical symptoms. Excessive salivation and mucosal inflammation of the mouth and throat may be seen in cases of mild parasite infection. A severe type of the infection can cause vomiting, ruffled feathers, diarrhea, loss of appetite, weight loss, dysphagia, dyspnoea, and a pendulous crop.

Greenish fluid and caseous lesions on the oropharyngeal membranes are signs of lesions that can form and hinder a bird’s ability to feed. Young birds are typically affected by trichomoniasis in pigeons and doves. It is believed that infection with nonvirulent strains or recovery from a mild infection are the basis for conferring immunity in birds.
The most frequent causes of protozoan proliferation in reptiles’ gastrointestinal tracts are inadequate husbandry or immunosuppression brought on by another illness. Weight loss, diarrhoea, and low appetite are clinical indicators of an elevated Trichomonas load. Trichomonas can occasionally spread to the gallbladder or bile duct, causing inflammation of the biliary system. There have been reports of ocular lesions in geckos caused by this protozoan.

Lesions:

• Early oral lesions- small cream to yellow spots on oral mucosa to large, thick, caseous lesions.
• Acute infections- Discharge, nodules in mouth.
• Chronic infections- Caseous lesions in mouth and oesophagus; may travel to beak and eyes.
• Lesions of pharynx and crop- Cream coloured to yellow and caseous and may extend to roof of mouth and sinuses.
• Necropsy findings- Fibrin covering the heart, liver, and air sacs may be observed.

Laboratory diagnosis:

• The different Samples are required for laboratory diagnosis i.e. Crop wash, Throat swab, Mucus and Faecal sample.

Differential diagnoses:

• Mycoplasmosis, Tuberculosis, Salmonellosis, Pigeon herpesvirus, Avian paramyxoviruses, Fowl adenovirus, Aspergillus spp., Candida spp., Capillaria and Vitamin A deficiency etc.

Prevention and control measure:

• Sanitation:
• It is advised to make sure feed is appropriately stored and contained in captivity or locations where feeding wild birds is prevalent such as backyard bird feeders to avoid dampness and unauthorized access by other birds. Day to day, change the water and feed.
• To lessen the chance of transmission, it is generally advised to dissuade sizable groups of doves and pigeons from congregating at feeding and watering locations.
• Group housings should be cleared of infected birds.
• Prior to housing wild reptiles with captive reptiles, check them for Trichomonas spp.
• Keep captive reptiles clean and eat a healthy diet to avoid an increase in parasite burden.

• Treatment
• Treatment of birds Infection with lentogenic strains to provide protection against virulent pathogens.
• Strategic antiprotozoal administration.
• Birds kept in custody for rehabilitation with apparent clinical disease, especially doves and pigeons, should be isolated until clinical indications go away.
• Examine doves and pigeons being fed to raptors for T. gallinae infection.

Impacts of the disease:

Risks to public health population

• There is no proof that T. gallinae is harmful to humans.
• T. vaginalis is a sexually transmitted infection that infects humans but is not thought to be a major cause of illness in birds and reptiles.
• Pet bird owners, pigeon breeders, raptors, and pigeon racers should limit their birds’ exposure to wild birds and take precautions to reduce infection.

Risks to industry

• Poor thrift of birds infected with this parasite has a negative economic impact on poultry businesses, including treatment costs and a reduction in production value (e.g., weight loss).