Cattle is one of the most hardy and unpretentious varieties of productive animals. Cows and bulls are sick quite rarely. However, sometimes health problems do occur in these animals. However, some diseases of cattle, unfortunately, can be asymptomatic. For example, sometimes cows become infected with cysticercosis. This disease belongs to the group of helminth infections.
What is a parasite?
Cysticercosis of cattle is caused by bovine tapeworm larvae. Moreover, the animals themselves are only intermediate carriers of this parasite. Adult tapeworm develops already in the human body.
The larva of this parasite is called a cysteric and is a bubble filled with a translucent gray liquid. Such a Finn has a head with four suction cups called a scolex attached to the bubble. The dimensions of the bovine tapeworm larva are quite large - up to 15 mm in length and up to 10 mm in width.
How do animals get infected?
Sick cattle cysticercosis due to the ingestion of parasite eggs in his body. In humans, bovine tapeworm is localized in the small intestine. The length of this worm can reach impressive - up to 10 m or more. The last mature segments of the tapeworm have a width of 12-14 mm. Branches with a length of about 2 mm extend from their main trunk in both directions. Each of these processes contains about 172 thousand eggs. On the side next to the joints is the genital opening.
In each egg of a bovine tapeworm there is an oncosphere - the embryo of a larva with 3 pairs of hooks. As the parasite matures in the human body, worm segments come off and are excreted with feces. In the environment, these formations can move independently over fairly large distances, shrinking worm-like.
If the infected person does not comply with hygiene standards, for example, defecation is not in the latrine, but in the field or in the yard, the segments of tapeworm creep in large quantities around the neighborhood, spreading eggs everywhere. In addition, public toilets with cesspools located on the street often become the source of this infection. Of course, worms can also be present in the wastewater of centralized sewer systems.
Cows are usually infected on pasture when they swallow segments and eggs along with grass. Also, cysticercosis of cattle is often infected at a watering place. In pastures, animals usually become infected when wastewater is used to irrigate nearby fields.
The development of a parasite in the body of an animal
Viability in the external environment can be maintained by tapeworm eggs for up to several months. Oncospheres hatch in the intestines of infected animals. After leaving the egg, the embryos immediately invade through the mucous membrane into small vessels, and then are carried by the bloodstream to the organs and tissues of the cow or bull. The development of the oncospheres in the cysteria occurs in the transverse cavity muscles. Most often, worms in cattle are affected:
skeletal muscle;
muscles of the tongue;
chewing muscles.
Also, the parasite can choose the place of its habitat heart, liver or brain of an intermediate carrier. According to various sources, the viability in the body of cattle in subsequent worms can remain from several months to 4 years.
How does a person get infected
Cisterns of bovine tapeworm usually enter the body of people when they eat unroasted, uncleared or underdone meat. By 3.5-4 months, the cysterics in the tissues of cattle reach their maximum value. From this moment, infection becomes possible.
In the human body, cysterics under the influence of bile turn the head out of the bladder outward and are attached to the intestinal mucosa through suction cups. In the future, the parasite begins to grow and develop rapidly. Bovine tapeworm in a human body reaches sexual maturity by about 2.5-3 months. In the subsequent year, only one such parasite releases about 51 million eggs into the environment.
The main symptoms in cattle
It is possible to determine that a cow or a bull is infected with tapeworm larvae only at the very early stage of the disease. Symptoms of cysticercosis in cattle during this period are:
increase in body temperature to 40 ° C;
poor appetite;
weakness;
heart palpitations and breathing;
soreness of the spinal, chewing and other muscle groups;
an increase in inguinal and scapular lymph nodes.
If such symptoms are found, the veterinarian will be required to go to the farm. Sometimes it happens that a few days after infection in an animal, the temperature rises sharply. The next day, it drops to 34 ° C. In this case, after about a day, the bull or cow die.
In most cases, however, at about 8-10 days after infection, the cattle begins to return to normal. By day 14, all external symptoms in animals completely disappear. By this time, the bulls and cows look completely healthy.
Veterinary Expertise
It is visually impossible to detect infection of animals with cysticercosis in the later stages. It is very difficult to diagnose this infection in the laboratory. During cattle life, various types of immunological techniques are usually used to detect the presence of parasites: intradermal allergy tests, RLA and RNGA. Most often, the veterinary and sanitary examination is carried out using the latest technology.
It is possible to determine the presence of cysteria in tissues with high accuracy only after cattle slaughter. In this case, equipment such as UV lamps is usually used for research. Under the influence of ultraviolet radiation, the cysterics begin to glow cherry or red and become clearly visible.
When conducting mascara studies, specialists usually check the masticatory muscles, heart and tongue. To a greater extent, cysts in cattle affect the front of the body. For examination during examination in meat, transverse and longitudinal sections are made.
If, when examined using UV lamps, it will be revealed that 40 cm 2 of muscle mass in the carcass contains more than 3 worms, the meat and offal are rejected. Dispose of them in the usual way.
With fewer parasites, meat can be disinfected by heat treatment and subsequently eat. Any operations associated with the preparation of the product, in this case, it is supposed to be carried out under the supervision of a veterinarian. The visit of a specialist to the place of work in this case is a prerequisite.
How a parasite behaves in cattle
Thus, the embryos of tapeworm, in fact, exert a pathogenic effect on cows and bulls mainly only during the period of active migration. Traveling through the body of the animal, the oncospheres primarily violate the integrity of the tissues. And this, in turn, often leads to inoculation of microflora.
Can cause certain harm to the body of livestock cysteria and subsequently. Their waste products often cause toxicosis in cattle. Sometimes in sick animals, allergic reactions also develop on the discharge of worms.
The grown cystics begin, among other things, to squeeze the surrounding muscle tissue. This, in turn, leads to the development of myositis. In places of large accumulation of larvae in tissues in animals, severe inflammation often begins.
An infected cattle with cysticercosis subsequently develops immunity to this parasite. Scientists also conducted experiments on the artificial immunization of animals for this disease. As a result, specialists have found that this method can be quite effective in the prevention of cysticercosis. It is quite possible that soon a similar technique to prevent the development of this disease will begin to be introduced in farms specializing in cattle breeding.
Can the disease be cured?
Diagnosing the presence of tapeworm in the tissues during the life of cows and bulls is thus quite difficult. Unfortunately, effective methods for treating cysticercosis of cattle have not yet been developed. Usually only Droncite is used to combat this parasite.
Measures for the prevention of cattle cysticercosis
Since it is practically useless to treat cattle from this parasite, it is important in farms to carry out various activities in a timely manner aimed at preventing its spread. Preventive measures against tapeworm include:
in disadvantaged areas, a ban on farm slaughter of cattle and the sale of meat without the permission of veterinarians;
tagging slaughter gobies and heifers;
thorough veterinary monitoring of the condition of farms and slaughter sites.
Also, for the prevention of contamination of animals and people with a tapeworm, farms are supposed to conduct medical examinations of employees. Such procedures should be performed at least 1 time per year, and even better - once a quarter.
Risk groups
It is believed that cattle with cysticercosis are most often infected in spring and autumn. Moreover, animals aged 1.5-2 years are most susceptible to this disease. Old cows and bulls are infected with tapeworm rarely enough.
In which regions does the disease occur
Cysticercosis is common, unfortunately, in all countries of the world. In addition to cattle, intermediate carriers of tapeworm larvae can be:
pigs;
buffalos;
gazelles;
wildebeest;
reindeer.
Most often, cows suffer from cysticercosis in the countries of Central Asia, Kazakhstan and Azerbaijan. In Russia, this infection is common in Dagestan, Yakutia, the Altai Territory and in the regions of the Non-Chernozem Territory.
Varieties
Among other things, scientists have identified several strains of worms that cause cysticercosis of cattle and pigs. The forms of this helminth may vary in terms of survival rate, duration of existence in the host organism, and location. For example, in Ethiopia, cysts accumulate in the body of cattle mainly in the liver. In Russia, such a phenomenon is quite rare.