Fascioliasis Of Cattle: Laboratory Diagnostics, Prevention And Drugs For Treatment

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Fascioliasis Of Cattle: Laboratory Diagnostics, Prevention And Drugs For Treatment
Fascioliasis Of Cattle: Laboratory Diagnostics, Prevention And Drugs For Treatment

Video: Fascioliasis Of Cattle: Laboratory Diagnostics, Prevention And Drugs For Treatment

Video: Fascioliasis Of Cattle: Laboratory Diagnostics, Prevention And Drugs For Treatment
Video: Parasitic Diseases Lectures #43: Fascioliasis 2024, March
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Page content

  • What causes the disease
  • Symptoms and routes of infection
  • Laboratory diagnostics
  • Drugs for treatment
  • Prevention methods
  • You can defeat parasites!

Fascioliasis of cattle and small ruminants is considered one of the most dangerous helminthiases of farm animals.

It is also found in pigs, rabbits, horses, donkeys, etc., as well as in wild animals. This disease is widespread and is recorded annually. A person can also become infected with fascioliasis.

What to do in such a situation? To get started, we recommend reading this article. This article details the methods of dealing with parasites. We also recommend contacting a specialist. Read the article >>>

What causes the disease

The causative agents of fascioliasis are trematodes (digenetic, or hepatic flukes), parasitic flatworms belonging to the Fasciolidae family and having two varieties: common fasciola (F. hepatica) and giant fasciola (F. gigantica) from the Fasciolidae family.

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1-Digenetic fluke, 2- Hepatic fluke

Fasciola vulgaris, prevalent in the European territory of Russia, resembles a brownish-greenish leaf in shape. The body length is small - 2-3 cm, the width is about 1 cm. In the gigantic fasciola, common in the southern and southeastern regions, the body is more elongated and larger in size, from 5 to 7 cm. There are small spines on the cuticle of the parasite, which is good seen in the photo and video.

The intermediate host for common fasciola is the small pond snail (Limnaea truncatnla), and for the giant one - the ear-shaped pond snail (L. auricularia).

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1-Fasciola vulgaris, 2-Fasciola giant

The life cycle of a helminth is as follows:

  • Eggs laid by sexually mature individuals come out with the feces of infected animals. Eggs are oval and rather large, golden yellow in color, with a cap on one of the poles.
  • Since the larva (miracidium) has not formed in the eggs, they are immature; to develop further, they need a freshwater environment in the form of a puddle, swamp, pond, etc. The presence of oxygen and a favorable temperature for development (15-30 ° C) for 2-3 weeks allow the formation of miracidia, which, after going outside, is introduced into the body, and then into the liver of the intermediate host - the pond snail.
  • In the liver of the pond snail, a sequential change in developmental stages occurs: first, the sporocyst, then the redia (if conditions are favorable, then the daughter redia also appears) and, finally, cercariae. This whole process continues in the body of the mollusk and takes 2 to 3 months.
  • One pond snail is able to give life to about 1.5 thousand cercariae, which, after coming out, literally in a matter of hours, pass into the stage of adolescaria, which attach to aquatic plants or are simply located on the water surface. Here they are swallowed by animals. Thus, we can talk about the alimentary route of infection.
  • After entering the intestines of the final host, the adolescaria is released from the protective membrane, then with the blood flow they penetrate into the bile ducts of the liver. They will need 3-4 months to reach sexual maturity; in general, fasciola is able to exist in the body of a definitive host for up to 3-5 years.
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Fascioliasis of cattle has its own seasonality of infection. As a rule, this is autumn, especially after a cool rainy summer, which creates ideal conditions for the appearance of a huge number of mollusks - intermediate hosts.

Eating grass or reeds, coming to a watering hole, cattle become infected with adolescaria. Spring is the period of the most severe outbreaks of fascioliasis.

Symptoms and routes of infection

Fasciols, parasitizing in the liver of cattle, have a pathogenic effect on its body, poisoning it with toxic products of its vital activity, causing nutritional disorders, edema, hydremia (an increased amount of water in the blood, causing a decrease in the concentration of erythrocytes), contributing to the penetration of intestinal microbes into others. organs, etc.

Clinical signs of fascioliasis are primarily due to the number of fascioli, which parasitize in the liver, and the number of which can reach two thousand.

It is believed that serious deviations in cattle develop when the number of parasites is more than 250 (in sheep - at least 50), but if we are talking about young animals, then a smaller number is sufficient for the appearance of characteristic symptoms.

In cattle, less pronounced clinical manifestations are observed than in small ones, however, during the incubation period, that is, during the first days after the invasion, the manifestations of the disease are obvious: fever, deterioration of appetite with possible vomiting, depressed behavior.

Giant fasciola infection is especially dangerous because after severe anemia within 3-10 days, the animal may die.

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Swelling of the lower jaw in cattle is the first sign of the disease

If timely treatment is not carried out, the disease turns into a chronic, less pronounced form: animals become lethargic, apathetic, lose their appetite and give milk of poor quality and in smaller quantities. So, milk yield can drop by 250 liters per year.

Dysfunction of the gastrointestinal tract is observed with a change in disorders of constipation. Against the background of exhaustion and progressive anemia, animals may experience anxiety, which is again replaced by apathy. Due to the large number of fascioli in the bile ducts, they expand and become denser, and over time, their calcification can occur.

As a rule, fasciola infestation occurs in late summer and autumn, when animals have access to natural pastures. This is considered the primary disease; the chronic course is possible all year round.

It is characterized by lethargy, anemicity, swelling of the eyelids, brittleness and loss of hair, as well as yellowness of the mucous membranes. The most intense mortality due to fascioliasis occurs in winter and spring.

Laboratory diagnostics

The main method of intravital diagnosis of fascioliasis is the study of fecal masses in order to detect helminth eggs, which the presence of a cap makes it well recognized. It is perfectly visible if a few drops of potassium hydroxide solution (caustic potassium) are added to the drug used for diagnosis.

However, the most reliable is postmortem diagnosis during veterinary examination: you can see with the naked eye both the fascioli themselves and the characteristic thickening of the bile ducts caused by them, etc.

Drugs for treatment

Treatment of fascioliasis should be carried out in a comprehensive manner, based on test results, taking into account the age and weight of the animal and other factors. The primary task is deworming, that is, the destruction and removal of parasites from the animal's body.

The following drugs have proven to be the most effective:

  • hexachloroparaxylene, which is used for both treatment and prevention; given twice with an interval of 10 days; the dosage is calculated by the weight of the animal;
  • hexachloroethane; is also given twice, but with an interval of 3 days. Important: to prevent atony (loss of tone by the muscles of the stomach) or tympania (swelling of the scar), concentrates and protein feed are excluded from the diet per day.

Along with these, other drugs are used: Acemidophen, Dertil, Ursovermit, Faskoverm, Geksihol, Ivomek, Disalan.

They are available in the form of tablets, suspensions, powders, preparations for s / c or i / m administration. When using these funds, it is necessary to strictly follow the instructions for the frequency of use and dosage, as well as special instructions regarding lactation, slaughter, etc.

Prevention methods

Prevention of fascioliasis in cattle involves the use of the above drugs, primarily hexachloroparaxylene, in winter and spring to prevent an outbreak of the disease.

If the epidemic does break out, it is recommended to transfer cattle to stall keeping.

To prevent invasion, it is required to take a number of measures aimed at destroying the vectors of the disease - molluscs:

  • drain wetlands in pastures and build drainage systems;
  • prevent cattle from accessing irrigated lands with the help of an “electric shepherd” - a wire fence through which an electric current is passed;
  • to process the habitats of mollusks with molluscicidal solutions;
  • for watering, use not irrigation canals, but imported water that has passed sanitary and epidemiological control;
  • periodically change the territory for pasture;
  • for preventive purposes, deworming cattle at least twice a year (before transferring cattle to stall keeping and then again after 2.5-3 months).

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