Cryptosporidiosis of calves: symptoms and routes of infection, methods of treatment of cattle

In calves, the immune system has not yet strengthened, the body is susceptible to negative factors, prone to diseases. One of the most common pathologies is cryptosporidiosis, which occurs in calves with varying degrees of severity. The disease affects not only cattle, but also pets and humans. The infection multiplies on the mucous tissues of the digestive tract, seizes the lungs, and in the absence of proper treatment causes the death of the animal.

Illness concept

Cryptosporidiosis is an infectious pathology that occurs in calves in acute and subacute form, caused by the simplest pathogenic microorganisms - coccidia belonging to the Cryptosporidium family.The infection captures the tissues of the stomach and intestines, which disrupts the function of digestion and absorption. Sometimes coccidia are transferred to the organs of the respiratory system, negatively affecting the immune system.

The intestinal mucosa is the first to be affected by infection. Moreover, the lesion is extensive, covering almost the entire organ. Due to a decrease in the absorption capacity of intestinal tissues, diarrhea begins. Intestinal villi swell and atrophy, and the number of mucus-producing goblet cells decreases. In the intestines, the synthesis of enzymes is significantly reduced, the concentration of sugars in the villi decreases.

Animals that have had cryptosporidiosis gain immunity. Therefore, there are no sick individuals among adult representatives of cattle.

Pathogens

The causative agents of cryptosporidiosis are coccidia of the Cryptosporidium family - round or oval microorganisms. The parasite cell is translucent, its membrane is almost transparent.Representatives of the family are smaller than other coccidia, but almost do not respond to antimicrobials. Cryptosporidium develops in the tissues of the host within 3-6 days, while passing through 3 life stages:

1. Sporogony - multiple division of a fertilized cell - oocysts, 3-7 microns in diameter. As a result, sporozoites are formed - mononuclear cells.
2. Merogony is a fragmentary development of a fertilized egg, in which there is no female nucleus.
3. Gametogony - sexual reproduction.

The shell of oocysts is dense and thin. The first is immune to external negative effects, ensures cell viability for 1.5 years. Oocysts with a thin membrane, although more sensitive, weakly exit the body, partially remain, provoking a second wave of the disease. Since coccidia are immune to antiseptic drugs and temperature fluctuations, they actively multiply both in the barn and outdoors.There are no farms where cryptosporidiosis pathogens could not be detected.

In 1 kg of cow manure laboratory analysis can detect more than 1 million oocysts.

Methods of infection

Calves are infected by the alimentary route, that is, the infection enters the digestive tract when swallowing contaminated food or drink. Less often, infection occurs through contact of the mucous membranes of the animal with equipment and care products.

Carriers of cryptosporidiosis are not only sick individuals, but also humans. For example, a farm worker can bring an infection on boots into a barn. Often, rodents living in a barn become carriers of cryptosporidiosis.

Symptoms of cryptosporidiosis

Having entered the body of a calf, cryptosporidium begins to multiply actively, causing inflammation of the intestines and respiratory organs. Incubation lasts from 3 to 6 days. Symptoms of cryptosporidiosis appear in calves 6-9 days after birth, and recovery occurs after about 2 weeks. Cryptosporidiosis proceeds with different intensity, depending on the immunity of the animal, the conditions of detention and the quality of care. The disease in calves is not chronic, only acute and subacute, that is, the pet either dies or survives.

The probability of death of a sick animal increases when cryptosporidiosis is complicated by eimeriosis, salmonellosis, clostridium.

The table lists the course of cryptosporidiosis and typical symptoms.

Symptomaticsmildlethargy, poor appetite, mild diarrhea with liquid or viscous fecal mass without mucous inclusions - symptoms are observed for several days, the calf recovers diarrhea with watery-mucous fecal matter - symptoms are observed for 6-8 days, the calf recovers with proper care and treatment

Form of course
calf lies down, can't get up, has no appetite, the body is dehydrated.The abdomen is painful, the diarrhea is profuse with watery-mucous feces, in which blood streaks are possible, the eyeballs grow dim and sink. The mucous membranes acquire a blue tint, the body temperature rises to 40-41 ° C, tachycardia, convulsions, loss of muscle sensitivity are noted, in the absence of competent and timely treatment, the infection affects the lungs, the calf dies

Diagnosis of pathology

For diagnosis, they take the feces of a sick calf. For post-mortem examination, fecal matter from the rectum is used. The diagnostic method used is a native smear. A dried fecal smear is fixed with methyl alcohol, giving it a carbol-fuchsin color. The oocysts turn red, and sporozoites are visible inside each cell under a microscope. The surrounding substrate turns green.

You can also use Giemsa's solution for staining - mixed azure, eosin and methylene blue. Under the microscope, oocysts look like cells that are faintly stained in a bluish-pink color. Inside the cell, light blue elongated and slightly curved sporozoites are visible.

How to treat cryptosporodiosis in cattle

There are no effective medicines. Treatment of cryptosporidiosis in calves involves the use of drugs:

• Amprolium;
• "Sulfadimezin";
• Norsulfazol;
• "Paromomycin";
• Khimkoktsid.

The first four drugs do not eliminate the infection, but only slow down the formation of oocysts in the body of the calf. And the last medicine from the list accelerates the production of immunity in the animal's body. These drugs should be used simultaneously with the course of immunostimulants. Abroad, these medicines are classified as unlicensed. Our farmers use them at their own risk.

Halofuginone lactate

The only licensed drug is halofuginone lactate. The drug is sold in the form of a liquid. It has a depressing effect on the stage of sporogony and merogony during the reproduction of the pathogen. Halofuginone lactate is suitable for both prevention and treatment of cryptosporidiosis. As a prophylactic, the drug is used 2 days after the birth of the calf. For therapeutic purposes, the remedy is used immediately after the onset of symptoms of cryptosporidiosis.

Halofuginone lactate does not eliminate the infection, but weakens diarrhea, inhibits the division of oocysts. Dose - 0.1 mg per 1 kg of body weight of the calf. But it must be borne in mind that the concentration of the active substance in the composition of preparations from different manufacturers is not the same. Therefore, to determine the dosage, you should read the instructions. The drug is given to the calf daily for a week, poured into milk. You can not give medicine to weakened pets, as well as with a duration of diarrhea for more than a day.

Auxiliary Therapy

To increase the effectiveness of the medicines used, the sick calf is put on a therapeutic diet. They put droppers for the introduction of solutions that normalize the water-s alt balance in the body. Give the calf decoctions that coat the walls of the diseased intestine, reducing inflammation.

Probiotic use

Probiotics do not work against coccidia. They are necessary to restore the intestinal microflora, ruined by the reproduction of pathogenic microorganisms and the use of drugs. Probiotics are dissolved in warm water, given to the calf to drink instead of one meal.

Problem Prevention

A vaccine against cryptosporidiosis has not been developed. Therefore, it is impossible to protect calves. Oocysts are tenacious, actively multiply, so even prevention causes difficulties. The main preventive measures are maintaining cleanliness in the barn, high-quality feeding and strengthening the immunity of calves.The bedding is changed regularly. The barn is disinfected, a solution of hydrogen peroxide and 10% formalin is used. Oocysts die at temperatures below -20 °C and above +60 °C. Therefore, thermal disinfection can be carried out: steam, boiling water, fire.

Farm workers should periodically take feces for analysis of the presence of coccidia. You should buy young animals only from trusted sellers who keep livestock in proper conditions. A sick calf is immediately separated from the herd.

Recommended