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The most dangerous parasites of farm animals are tapeworms or tapeworms. They are dangerous not because they cause economic damage to animal husbandry. Infected animals just practically do not suffer from these types of worms. Man suffers from them as the ultimate host of the parasite. The larvae of one of the tapeworm species cause finnosis in cattle and subsequent human infection with a long-lived worm up to 10 m long and with a life expectancy of 10 years. But with the help of a bull tapeworm it is good to lose weight. You can eat anything and as much as you want. But of course this is sarcasm.
What is bovine cysticercosis
A more correct name for the finnosis of cattle is cysticercosis. But Finnoz is easier to pronounce and remember.
The “ancestors” of cysticercosis are tapeworms of various species from the genus Tenia, they are also Cystodes. These parasites are most common in relatively warm regions:
- Africa;
- Philippines;
- Latin America;
- Eastern Europe.
But you can also meet them in Our Country. Especially taking into account the widespread import of elite breeds of cattle from Western countries to the Federation.
Cattle are infected not by helminths themselves, but by their larvae, which even have their own Latin name: personal for each species. Therefore, in fact, cysticercosis of cattle is the infection of livestock with the larvae of the bovine tapeworm.
In cattle, larvae of other tapeworm species may also be found, but their localization differs from the location of bovine cysticercus.
This is not a ribbon, but the “culprit” of the Finnose cattle – a bull tapeworm, whose length is 10 m. The head is on the right
Life cycle of tapeworm and infection of cattle with finnose
The adult parasite can only live in the human small intestine. The mouth of the worm sticks to the mucous membrane and grows, gaining a length of 2-5 thousand segments. If a tapeworm has settled in a person, it is very difficult to expel him. When using anthelmintic drugs, the parasite sheds segments, but the head remains attached to the wall of the small intestine. From the head of the tapeworm and begins to grow again. Of course, it is possible to “finish off” the worm with potent drugs. But if no measures are taken, then according to various sources, its lifespan in the intestines can be from 10 to 20 years. Each year, the tapeworm produces up to 600 million eggs.
Oncospheres enter the external environment with human excrement. So in medicine and veterinary medicine they call tapeworm eggs.
In the intestine, the worm sheds mature segments filled with eggs. These “capsules” and “pass” through the gastrointestinal tract the rest of the way. Cattle become infected with oncospheres by eating contaminated feed.
Through the intestinal wall, oncospheres penetrate into the blood, which carries them throughout the body. But the further development of the larvae occurs in the muscles. There, oncospheres turn into cysticerci, causing finnosis / cysticercosis in cattle. The parasite does not cause any particular harm to its intermediate host, patiently waiting for the herbivore to get a predator for lunch. Or a person.
Infection of a person occurs when eating poorly processed thermally meat. And the tapeworm life cycle starts all over again. Comment! In humans, this invasive disease is called teniarhynchosis.
The life cycle of the bovine tapeworm, including the Finnose of cattle and human teniarinhoz
Types of Finnose cattle
Strictly speaking, there is only one type of bovine finnosis: the one caused by Cysticercus bovis, a larva of Taeniarhynchus saginatus/ Taenia saginata (in this case, the Latin names are synonymous). And in a simple way: finnosis in cattle is caused by a larva of a bull tapeworm. Although, given the ultimate host of this parasite, it would be more correct to call the worm “human”.
But cysticercosis, which can affect cattle, is not limited to finnose. Somewhat less often, but cattle can become infected with other tapeworms. The ultimate hosts of the tapeworm species Taenia hydatigena are carnivores, to which humans can rightfully be attributed today. In nature, scavengers become infected by eating the carcass of a fallen infested animal. A person can acquire a tenant if he uses the internal organs of farm animals.
Just like a bull tapeworm, the tapeworm of carnivores “sows” the segments into the environment. Herbivores, eating food contaminated with excrement of predators, become infected with tenuicol cysticercosis. Animals susceptible to infection with this type of cysticercosis:
- sheep;
- goats;
- pigs;
- cattle;
- other herbivores, including wild species.
Once in the intestine, the oncospheres migrate with blood to the liver, pierce the parenchyma, and enter the abdominal cavity. There, after 1-2 months, the oncospheres turn into invasive cysticerci.
Tenuikolny cysticercosis differs from the finnosis of cattle in that it is distributed almost everywhere. It does not have areas of maximum distribution, like the Finnose. The only thing that helps out is that cattle are less likely to become infected with tenuicol cysticercosis than with finnosis.
Another type of cysticercosis is “cellulose”, also called finnosis. But Taeniasolium larvae do not parasitize cattle. They hit:
- cats;
- bears;
- pigs;
- dogs;
- camels;
- rabbits;
- person.
Cysticercosis caused by Cysticercus cellulosae is also called porcine finnosis. For the tapeworm, a person is both an intermediate and a final host. If we get lucky”.
They just call these diseases in a different way. And the intermediate hosts for other cestodes are different.
When carefully cutting the carcass of cattle infected with finnose, you can see cysticerci. These are the white dots in the photo.
Symptoms of Finnos cows
The manifestation of clinical signs of cysticercosis depends on the degree of infection. If it is mild, the animal may not show symptoms at all. With a strong infection of cattle with cysticercosis bovis observed:
- increased body temperature;
- weakness;
- muscle tremors;
- oppression;
- lack of appetite;
- frequent breathing
- intestinal atony;
- diarrhea;
- groans.
These signs last for the first 2 weeks, while the larvae from the intestines migrate to the muscles. Then the symptoms of finnosis disappear, the animal “recovers”. The owner is happy that everything worked out.
Signs of infection with tenuicol cysticercosis are noticeable only during the acute course of the disease, while the larvae migrate through the liver to the site of localization:
- heat;
- refusal to feed;
- frequent heartbeat and breathing;
- anxiety;
- icteric mucous membranes;
- anemia;
- diarrhea.
With a strong infection with tenuicol cysticercosis, young animals may die within 1-2 weeks. Further, the disease passes into the chronic stage and proceeds with uncharacteristic signs or asymptomatically.
Diagnosis of cysticercosis in cattle
An intravital diagnosis of cysticercosis in cattle is made using immunological methods. But it is possible to determine exactly which type of cysticercosis an animal suffers only posthumously.
The diagnosis is usually made only after the slaughter of the animal. With cysticercosis of cattle, the localization of the larvae occurs in the striated muscles. In a simple way, in the very beef that comes to the table in the form of steaks, entrecote and other goodies. True, one must be very careless in order to take up the preparation of this meat. If the cattle is infected with cysticercosis, it is not necessary to look at the meat under a microscope: the diameter of the bubbles located between the muscle fibers is 5-9 mm.
This is how the meat of an animal infected with cysticercosis of cattle looks like in the photo
They are clearly visible to the naked eye. But you can play naturalist, take a microscope and admire the double shell and one scolex of a cysticercus that causes finnosis of cattle.
When infected with cysticerci, the carnivorous Taenia hydatigena larvae are even more difficult to miss. Cysticercus tenuicollis are localized in internal cavities and organs and are about the size of a chicken egg. And if you want, you won’t miss it.
In the acute course of tenuicol cysticercosis in dead young animals, changes are found in the internal organs:
- the enlarged liver has a clay color;
- on the surface of the liver, petechial hemorrhages and tortuous bloody passages in the parenchyma;
- in the abdominal cavity, a bloody fluid in which fibrin and small translucent white vesicles float.
These vesicles are the migratory cysticerci of the carnivorous tapeworm. When washing the crushed liver, young larvae are also found.
Cysticercus tenuicollis in cardiac muscle
Treatment of cysticercosis in cattle
Until recently, all reference books indicated that the treatment of Finnoses has not been developed, since the larvae in cysticerci (capsules-spheres) are well protected from the action of anthelmintic drugs. Sick cattle are slaughtered and the meat is sent for deep processing. In a sense, they make meat and bone meal from carcasses, which then goes to fertilizers and animal feed.
Today, Finnose cattle are treated with praziquantel. The dosage is 50 mg/kg of live weight. Praziquantel is administered for 2 days. The drug can be pierced or added to the feed. The manufacturer of the drug is the German company Bayer. But it must be borne in mind that complete confidence in the cure of an animal from finnosis of cattle can only be obtained after slaughter and examination of cysticerci under a microscope (live or dead).
However, for the owner of dairy cattle, only the acute stage of cattle finnosis is dangerous, when the larvae migrate into the muscles. At this time, cysticerci can also enter the milk ducts. Later, it will no longer be possible to become infected through milk.
Preventive measures
Prevention of cysticercosis in cattle has to be carried out not only on the farm where the infection was found, but throughout the region. Domestic slaughter of animals is prohibited. All cattle meat that comes from farms and from settlements in the affected area is carefully controlled. Restrict the movement of stray animals. Simply put, stray dogs are shot, and the owner’s dogs are required to be put on a chain.
Animals sent for slaughter are marked with tags in order to find out the foci of infection with finnosis and to identify people with teniarhynchosis. Carcasses infected with cysticercosis are neutralized following veterinary and sanitary rules.
Farm personnel are quarterly examined for infection with taeniarhynchosis. People found to have a tapeworm are suspended from serving animals.
Unroasted meat of an animal with finnosis is the source of the appearance of this cute pink worm in the human gastrointestinal tract
Threat to human
The cysticercus that got into the human body along with uncooked cattle meat quickly turns into a young tapeworm. The worm grows and after 3 months begins to shed mature segments.
It is “unprofitable” for the parasite to be quickly detected, and the most common sign of infection with teniarinhoz is the allocation of these same segments. “Capsules” may appear to be separate organisms, as they partially show signs of small flatworms: they crawl. The patient also feels itching around the anus.
Due to the fact that the beast is already large inside, the patient may experience:
- nausea and urge to vomit;
- bouts of abdominal pain;
- increased appetite with weight loss;
- sometimes appetite decreases;
- weakness;
- digestive disorders: diarrhea or constipation.
Sometimes there are signs of allergies. Few people associate other signs with helminthic invasion:
- nosebleed;
- dyspnea;
- palpitation;
- noise in ears;
- flickering black dots before the eyes;
- discomfort in the region of the heart.
With multiple infection with bovine tapeworm, dynamic intestinal obstruction, cholecystitis, internal abscesses, and appendicitis are noted.
The discarded segments, showing a fair amount of mobility, can get through the Eustachian tube into the middle ear or into the respiratory tract. To do this, they first need to get into the oral cavity, which they do, standing out with vomit.
In pregnant women infected with bovine tapeworm, the following are possible:
- spontaneous abortion;
- anemia;
- toxicosis;
- premature birth.
Here is such a “cute and very useful for weight loss” worm that can start in a person:
Conclusion
Finnosis in cattle is dangerous not so much to the animals themselves as to humans. It is almost impossible to remove larvae from muscle fibers. Even after the application of praziquantel and the death of the larvae, the spheres themselves will remain in the muscles.