Helminths In Dogs And Cats, Classification And Methods Of Dealing With Them

2024 Author: Sebastian Paterson | [email protected]. Last modified: 2023-12-16 13:47

Why not see and hear enough, working in a pharmacy or clinic! I’m standing at the checkout the other day, there’s no one, I’m glad for a short break.

A lady from among regular customers comes and asks to see what kind of worms her dog with diarrhea gave out. I try to excuse myself by the fact that, firstly, without special equipment, I still cannot determine the species, only flat helminths or round ones, and, secondly, it makes no difference, because modern veterinary anthelmintic drugs act on both others. The lady insists and brings the worms in a jar.

Well, well, she deserved these screams of mine:

- Oh! How lovely! Look at this characteristic "chopped off" head! But - see? See? - the rudiments of the eye! How lovely! Yes, these are not worms at all! It was your dog that ate the rotten stuff together with the larvae of the flies!

For this labor feat of mine, I was rewarded with a package of smoked sausages and a children's microscope LOMO.

On this example, we can make sure that this problem is relevant and interesting. This cannot but rejoice doctors, because the interest of animal owners in the diseases of their pets is a guarantee that the animals will be properly looked after, vaccinated, given anthelmintic drugs, and so on. This means that doctors will have fewer problems and less work.

So, about the worms. Colleagues can reproach me for using incorrect, everyday terms. It is correct, of course, to say not worms, but helminths, and not anthelmintic drugs, but anthelmintics, but … The magazine is read not by parasitologists, but by ordinary people. I will write in a way that makes them understandable.

What interests us about these harmful worms? Firstly, how do they threaten our pets and us, secondly, how can you get infected with them (and for this you need to know the developmental cycle of worms), and, thirdly, how to get rid of these harmful companions of life without harming your pet. Well, let's talk about it.

Opisthorchiasis is a helminthic invasion caused by the fluke Opisthorchis felineus, a parasite in the bile ducts of the liver, gallbladder and pancreas of humans and many animals, including cats and dogs. Opisthorchiasis is distributed focal in the basins of large freshwater rivers - the Volga, Ob, Irtysh, Northern Dvina, Dnieper. Infection occurs when eating infected fish from dysfunctional water bodies. In sick animals and humans, all signs of liver damage are expressed: the liver is enlarged, painful, there may be colic, icteric mucous membranes, unstable stools (diarrhea and constipation alternate), emaciation. The course is very difficult.

Helminths are divided into flat (flukes and tapeworms), round and spiny-headed. Some of the most dangerous, including for humans, are flukes (Trematodes). The most famous disease caused by flukes is opisthorchiasis, although there are several more similar diseases. Chains (Cestodes) are long flat worms armed with suction cups and hooks. Many of them parasitize on our pets. Echinococcosis, alveococcosis are dangerous for humans, and, extremely rarely, multiceptosis. Roundworms (Nematodes) cause toxocariasis, toxascaridiosis, tychinellosis. A person suffers from all these diseases, and toxocariasis and toccariasis are especially dangerous for children and pregnant women.

Trichinosis is a helminthic invasion caused by the round helminth Trichinella spiralis, which in the adult state parasitizes in the intestines of carnivores and omnivores and humans, and in the larval - in their muscles. Animals and humans become infected by eating meat infested with Trichinella larvae. In the intestine, the larvae grow into adults and give birth to new larvae. Unfortunately, this process is often asymptomatic and not a cause for concern. Then the larvae are carried by the bloodstream into the muscles and covered with a dense, durable capsule. Sometimes there is an asymptomatic course of trichinosis, but usually at this moment the clinical signs are most pronounced (severe allergies, fever, muscle pain), and treatment is already useless. In no case should you eat and feed untested pork and game to animals !!!Contaminated meat must be destroyed!

The severity of the disease depends on the degree of invasion (lesion), age (puppies, kittens and old animals are seriously ill), the state of the body's immune system. In some cases, helminthiasis are completely asymptomatic, in others, the symptoms are blurred, especially for lesions with tapeworms (unstable stools, nausea on an empty stomach, pruritus, allergic reactions, slow growth, perverted appetite), in third, the signs are more characteristic: enlargement and soreness of the liver, yellowness of the mucous membranes (opisthorchiasis), bloated stomach, colic, blood in the feces, nervous disorders, pallor of the mucous membranes, often - the release of worms with vomit and feces (ascariasis).

How does the infection take place? All worms are divided into GEO- and BIOHELMINTS. What is the difference?

Toxocariasis and toxascariasis are helminthic infestations caused by round helminths Toxocara canis, Toxocara mystax, Toxascaris leonina. Sexually mature nematodes are parasites in the intestines of dogs and cats. The course of the disease can be from asymptomatic to very severe: anemia, exhaustion, colic, convulsions, intestinal trauma, up to its rupture and death. The period of migration of larvae in the body is even more dangerous: they pass through the liver, heart, lungs, uterus, causing damage to these organs and a strong allergic reaction. Thus, intrauterine infection of kittens and puppies occurs. Although the larvae cannot grow into sexually mature individuals in the human body, the same processes occur when the eggs of these helminths enter the human digestive tract. Children under 4-5 years of age are most seriously ill. The disease is dangerous for pregnant women. Human infection occurs when hygiene rules are not followed and during the games of children in places where dogs are walking.

Geohelminths do not have an intermediate host, eggs with feces fall on the ground (grass, etc.), having swallowed these eggs, the next victim becomes infected (or even the previous host itself is re-infected). The causative agents of toxocariasis, toxascariasis, and ankylostomatidosis belong to geohelminths. All of them are dangerous for humans. The larvae of toxocar, toxascride and hookworm contribute to allergization (asthma, skin allergies, and so on) of the body, spread throughout the body through the blood vessels, where they can encapsulate and cause damage to these organs (imagine a foreign body in the brain or in the tissues of the eye). Toxocara larvae can even droop into the uterus, causing deformities and fetal death (by the way, unborn puppies and kittens become infected in this way). Children under 4 years of age are especially seriously ill. Hookworm larvae enter the human body through the skin, causing dermatitis and introducing microflora. Infection of a person can occur not only if the rules of hygiene are not followed (unwashed hands), but also when children play - Easter cakes, secrets, and the like - at the place of walking the dogs. That is why it is so important to organize as many special dog walking areas as possible! Communication is great, but you have to go to the toilet individually.

Biohelminths necessarily have an intermediate (and sometimes an additional) host. Knowing this, these parasites can be dealt with by destroying or protecting intermediate hosts.

Dipylidiosis is a helminthic invasion caused by the tapeworm Dipylidium caninum, a parasite in the intestines of dogs and cats. It is extremely rare for a person to get sick. The clinical signs are the same as in other cestodoses. A feature of dipylidiosis is that fleas are the intermediate host. The flea larva, crawling in the dust and feeding on its organic particles, swallows helminth eggs. In the body of a flea, a larva forms from an egg. A dog or cat, biting off adult fleas that bother it, swallows them and becomes infected with dipylidiosis. It is impossible to cope with this disease without the destruction of fleas.

In the causative agent of opisthorchiasis, the intermediate host is freshwater molluscs, the additional host is freshwater fish, therefore, by destroying mollusks and carefully boiling and frying the fish, we protect ourselves and our pets from invasion. A person becomes infected not from a pet, but from improperly cooked fish.

In causative agents of diphyllobothriasis and corynosomatosis, the development cycle is similar: the intermediate host is freshwater cyclops crustaceans, the additional one is fish that eat these crustaceans.

The causative agent of dipylidiosis is carried by fleas. That is why the animal should be protected from fleas, and if there are fleas, after anti-flea drugs, it is imperative to use anthelmintics.

Echinococcosis - helminthic invasion caused by the tapeworm Echinococcus granulosus and alveococcosis - the helminthic invasion caused by the tapeworm Alveococcus multiocularis parasitizing in the final hosts (echinococcosis - dogs, alveococcosis - dogs, cats, furry animals depending on the degree of intestinal lesions) in them and the state of the immune system, digestive disorders, exhaustion, pruritus, perverted appetite, allergies, can be completely asymptomatic. These helminths are much more dangerous for intermediate hosts, which include humans. Getting into all organs and tissues with the blood stream, the embryos grow into larvae that look like bubbles of various sizes (up to 20 cm in diameter). Depending on the location of the bladder, a person has digestive disorders, difficulty breathing and coughing, bone fractures, blindness,paralysis and so on. Since dogs and cats secrete helminth eggs with feces, human infection occurs when hygiene rules are not followed, and in children - when playing in places where dogs are walking.

The intermediate hosts of shades are cows, sheep, goats and pigs. Our pets (and in some cases we too) are the ultimate owners, so the main defense is to buy only meat that has been verified by veterinary and sanitary experts. A person should only eat well-done or cooked meat. To protect cattle and pigs, dogs should not be walked in the grazing (walking) areas of these animals.

The same applies to the causative agents of multiceptosis (intermediate host - cattle, extremely rarely - humans), echinococcosis (cattle, pigs, humans), alveococcosis (rodents, cattle, pigs, humans), just remember that in these cases a person is not the final, but an intermediate owner, that is, he gets infected from dogs! In the body of the intermediate host, the larvae enter various organs and tissues, where they grow to the size of a chicken egg, or even the head of a newborn baby !!! These huge bubbles squeeze organs and tissues, disrupting their activity, up to blindness, paralysis and convulsions.

In the causative agents of hydatigerosis, moles and rodents are intermediate hosts, therefore their destruction is one of the preventive measures.

Trichinosis affects all omnivores and carnivores, including humans, but infection does not occur by contact, but when eating meat, and neither freezing nor boiling does not destroy the larvae. The disease is very difficult. Often - fatal. It is strictly forbidden to eat and feed animals untested pork (including boar meat), bear meat and other game. Contaminated meat must be destroyed.

Fearfully? Well, you now know the ways of infection, and whoever is warned is armed!

Now about how to get rid of uninvited neighbors. I sit, leafing through textbooks and reference books 13-18 years ago. What a horror: hexachloroethane (also used to fight flies, ticks, mosquitoes, when applied, changes in the blood picture, exhaustion, paralysis are possible), fern extract (has an irritating property for the stomach and intestines, can cause vomiting, diarrhea, in pregnant women - miscarriages), tetrachlorethylene and carbon tetrachloride (toxic substances, especially for young animals), each of these drugs acted only on flat or only round helminths, and also required the use of a laxative, and for some diseases, no treatment at all was developed.

Fortunately, there are now many anthelmintic drugs available. Almost all of them, unlike medical ones, consist of 2-3 active substances that destroy both flat and round and spiny-headed worms. The most common of these are praziquantel and pyrantel.

PIRANTEL (pirantel, combantrin) is a drug for the destruction of larval and sexually mature forms of intestinal nematodes. Mechanism of action: blocks the conduction of nerve impulses in helminths, due to which paralysis of the muscles occurs. Since roundworms are retained in the intestine of the host only due to active movement (they swim against the current all the time), paralyzed, they are easily removed from the intestine. Pyrantel is poorly absorbed from the digestive tract, therefore it does not act on the host and is mainly excreted in the feces.

PRAZIKVANTEL (praziquantel, cesol, droncite) is a drug for the destruction of young and mature forms of flatworms. Mechanism of action: damages the cell membranes of helminths, due to which membrane transport is disrupted, the leaching of calcium ions begins, carbohydrate metabolism is disrupted and parasites die. It does not affect warm-blooded animals (we have no cell membranes). Praziquantel is well absorbed from the digestive tract, quickly decomposes and excreted in urine and feces, without accumulating in the body.

Modern veterinary anthelmintic drugs also have a mild laxative effect. As a rule, these drugs are given once for prophylaxis or twice with an interval of 7-10 days in case of confirmed invasion. A special diet is not required in advance (although it is advisable to give it in the morning on an empty stomach, and feed it after a walk). The only exception is that for the expulsion of trematodes parasitizing in the liver (opisthorchiasis), choleretic agents should first be given. The advantage of veterinary drugs over medical ones is also that they exist in different dosages and different forms of release. There are tablets, syrups and sugar. For babies, tablets are designed for 1 kg of weight, syrup - 1-2 ml per kg of weight. For adult cats, syrup is given at the rate of 1 ml per kg of body weight, and tablets are usually calculated for 4 kg of body weight (average cat weight). For adult dogs, syrup is given at the rate of 1 ml per 3 kg of weight, tablets and sugar - 1 piece per 10 kg of weight, some of these preparations are also suitable for cats (up to 5 kg of weight - half, fat - whole). And, of course, one should (as prescribed by a doctor) use vitamins, immunostimulants, symptomatic drugs.

Of course, for complete confidence, it is necessary to analyze the feces, but it should be remembered that eggs are not found in every portion, so a one-time negative result does not mean anything … Using anthelmintic drugs, you can be sure that your animal is free of worms. Many drugs even have stickers, which, certified by a veterinarian, indicate that the animal does not have worms, and replace the test result with worm eggs (necessary, for example, to participate in an exhibition).

So, follow the rules for walking dogs, do not give your animals meat and fish that have not been tested by veterinary and sanitary experts (it is generally better to exclude fish from the diet or boil well), protect animals from flea attacks, use preventive supplements with garlic and pumpkin seeds, do not use anthelmintic drugs less often 2 times a year (and preferably once a quarter) - and your pets will not have any problems.