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Colibacillosis in calves is caused by microorganisms that live in the intestines of cattle. The disease has another name – escherichiosis of calves. It is characterized by severe dehydration, general intoxication of the young calf’s body, after which death often occurs. The disease can overtake cows even in adulthood. An individual who has suffered colibacillosis becomes a carrier of this infection. However, dairy calves under the age of one week, as well as animals with weakened immune systems, are most often exposed to escherichiosis.
What is colibacillosis
Colibacillosis is an acute infectious disease of the gastrointestinal tract of young animals. It occurs in the first days after the birth of a calf and has different forms of manifestation. It is characterized by the entry into the body of pathogenic species of Escherichia coli that have invasive properties. Escherichia coli (Escherichia coli) can enter the calf's body through dirty udders and milk, which contains the infectious agent. A sick newborn calf releases microorganisms in its urine and feces into the external environment.Thus, all young animals on the farm can become ill with colibacillosis.
Colibacillosis was first identified at the beginning of the 19th century. Professor Obich established that this disease is infectious and dangerous for the entire population. They called the disease white sucker diarrhea. It was further determined that colibacillosis has different forms of manifestation. In the twentieth century, research was continued by such veterinary specialists as Vishnevsky, Mikhin, Tsven and others. They discovered serotypes, developed methods of treatment and prevention of colibacillosis.
The causative agent of colibacillosis in calves and cows is pathogenic strains of Escherichia coli. They are classified as gram-negative anaerobic microorganisms that are capable of producing toxins. It is they that cause dysbiosis in the calf’s body, inflammation of the intestines, stomach and other digestive organs, as well as lymph nodes. E. coli are not resistant to environmental changes. When boiled, they die instantly, in hot water up to 60 ° C - after 15-20 minutes. In soil and a humid environment they can live for 3-4 months. Among the disinfectants, bleach, phenol and formalin act on the causative agents of colibacillosis. Other disinfectants are not so effective.
The disease has several stages: acute, subacute and hyperacute. In addition, depending on localization, colibacillosis can occur in three forms:
- enteric - a rather mild form in which bacteria inhabit the mucous membrane of the small intestine of the calf, releasing endotoxin;
- the enterotoximic form of colibacillosis develops when microorganisms attach to the epithelium, releasing an exotoxin that disrupts intestinal motility and makes it difficult to eliminate harmful substances;
- the septic form is the most complex, since the pathogen penetrates the blood and lymph.
Any of these forms of colibacillosis will require immediate veterinary attention, otherwise the disease will be fatal.
Colibacillosis is widespread. Most outbreaks of the disease are recorded during the calving season - in winter and spring. Most often, cattle are susceptible to infections when kept in stalls. An epidemic of colibacillosis occurs when the causative agent of the disease appears when its maximum concentration is reached and when there are routes of infection for further spread of the infection. Experienced farm owners fight colibacillosis in calves using a special vaccine.
Causes of escherichiosis in calves
Like all other infectious diseases of the gastrointestinal tract, colibacillosis is transmitted by the fecal-oral route. The sources of the disease can be:
- non-compliance with sanitary and hygienic rules by farm personnel;
- infected food, contaminated water;
- milk, colostrum from a sick cow that is a carrier of colibacillosis;
- dirty udder;
- stale bedding, contaminated equipment;
- lack of timely vaccination of calves;
- urine, feces of infected animals.
In addition, there are a number of factors that negatively affect the development of the disease.These include poor conditions for keeping cattle, inadequate, unbalanced nutrition of animals, low-quality feed, lack of vitamins and microelements in the diet. An important factor is the genetic predisposition of the calf to colibacillosis.
Symptoms of colibacillosis in calves
Clinical manifestations of the disease depend on the form of colibacillosis, as well as on the age of the calf.
The subacute course of the infection is more typical for the enteritic form of the disease. Calves that were born more than a week ago usually get sick. They begin to develop diarrhea, their general condition worsens, and conjunctivitis develops. They spend most of their time lying down, and some instability is noticeable when moving. Animals often develop complications: pathologies of the knee and hock joints, rapid breathing, nasal discharge.
In newborn calves up to a week old, colibacillosis occurs in an acute form. Children have foaming diarrhea, no appetite, and general condition is weak. Traces of blood, mucus, and clots of colostrum are noticeable in the stool. The temperature can rise to 41-42 °C. The calf's belly is swollen, the mucous membranes are pale, and all signs of dehydration are present. But with timely treatment of colibacillosis, the prognosis is favorable.
The mortality rate of calves with hyperacute development of colibacillosis reaches almost 100%. The disease manifests itself in the first three days of the animal’s life. Characterized by increased temperature and rapid exhaustion. The calves are lying down and have no appetite. Within a few days they die from sepsis.
The enteritic form of the disease is characterized by:
- constant diarrhea;
- there is blood and mucus in the stool;
- dehydration, exhaustion;
- sunken sides, eyelids.
The septic form of colibacillosis manifests itself:
- general depression of the calf's condition;
- increased heart rate and breathing;
- increase in temperature;
- diarrhea is not observed.
Sometimes colibacillosis occurs in a mixed form. In this case, all symptoms manifest themselves simultaneously to a greater or lesser extent.
Diagnosis of escherichiosis in cattle
An accurate diagnosis is established based on laboratory tests. They include biological, serological, bacteriological and microscopic diagnostic methods. From calves, feces are taken for analysis from the rectum or after defecation. The laboratory determines the strain and then begins drug therapy.
The microscopic method allows you to recognize the causative agent of colibacillosis in a stained and unstained state using a microscope. A biological or experimental research method artificially reproduces the clinical picture of an infection in laboratory animals and makes it possible to identify the pathogen. Serological identification of a microorganism is based on the determination of antibodies and antigens using reactions. Bacteriological studies, which take place in several stages, reveal a pure culture of bacteria.
The diagnosis of colibacillosis is considered established in the following cases:
- when isolating a pure culture of Escherichia from no less than two organs or tissues (blood, bone marrow, spleen, heart), without determining their pathogenicity for mice or chickens;
- isolation of Escherichia with 1-2 types of antigens from the test material;
- secretions from Escherichia material, which belong to pathogenic serogroups.
Treatment of colibacillosis in cattle
Once an accurate diagnosis has been made, treatment for the calf should begin immediately. Veterinary specialists use bacteriophage, gamma globulin, and hyperimmune serum against colibacillosis in calves. Of the antibiotics, levomycin, biomycin, gentamicin and some other drugs are considered the most effective. To remove toxins from the calf's body, symptomatic medications are prescribed. In addition, it is necessary to replenish the loss of vitamins, microelements and fluids.
First of all, a sick calf must be isolated from its mother and transferred to a separate room. Instead of milk as a nutrient, you should give your baby saline solution with a raw chicken egg. Before use, antibiotics are diluted with water and taken strictly according to the clock several times a day.
Camphor oil and caffeine are administered subcutaneously in case of severe exhaustion of the calf. The serum is also used only subcutaneously. After neutralizing the stomach contents with a water-salt solution, the bacteriophage is administered orally. To remove toxins from the body and restore intestinal microflora, you need to give the calf enemas. After treatment of colibacillosis with antibiotics, the calf must be prescribed probiotics, for example, bifidumbacterin or enterobifidin.
Infusions and decoctions strengthen the calf’s immune system, suppress the growth of harmful bacteria, and improve the function of the gastrointestinal tract. However, they can be used as an adjuvant therapy after consultation with a specialist.
Therefore, treatment of colibacillosis should be comprehensive. Only then will the therapy be effective and give the expected result.
In addition to drug treatment, the calf must be on a strict diet from the onset of the disease. It is important to take care of restoring the water-salt balance in the baby’s body, as well as neutralizing the effects of toxins. You will need to replenish the loss of fluid and energy. Calves who have recovered from colibacillosis should be given vitamin supplements and microelements in their feed. After treatment, it is recommended to carefully monitor the general condition of the calf and its bowel movements. It is necessary to transfer the animal to its usual diet gradually, without loading the mucous membrane of the stomach and intestines.
Pathological changes in colibacillosis in calves
The corpse of an animal that died from colibacillosis is characterized by general exhaustion, sunken sides, and thin limbs. The calf's fur is dull, the area around the anus is stained with feces, and the skin is inflamed. The subacute form of colibacillosis is accompanied by damage to the respiratory system. In addition, the following changes are observed:
- hemorrhagic inflammation in the large intestine;
- joint swelling;
- inflammation of the stomach walls with hemorrhages;
- swelling of the veins;
- damage to the mucous membranes of the eyes;
- the gallbladder is full and distended;
- inflammation of the lymph nodes;
- dystrophic changes in the myocardium;
- enlarged spleen;
- signs of anemia in the liver, kidneys, mucous membranes.
At autopsy, the specialist notes traces of curdled milk in the abomasum, and remnants of undigested food with mucus in the intestines. Multiple hemorrhages are visible on the peritoneum.
Prevention of colibacillosis in young farm animals
To prevent colibacillosis in calves, a set of preventive measures should be carried out on the farm.The most important thing that a cattle owner must do is to carry out a mandatory two-time vaccination a month before the cow calving. Calving should take place in clean conditions. Newborn calves should be left with their mother for a day and then placed in a specially disinfected box. All calves on the farm must be kept in a separate room and young animals must not be allowed to come into contact with adults.
Other preventive measures include:
- compliance with all basic sanitary and hygienic standards in the barn;
- cleanliness of staff and care items;
- at calving the calf should be received in fresh straw or burlap;
- proper feeding of a pregnant cow;
- vitamins and microelements in the diet;
- regular cleaning and disinfection of the barn;
- separate calving area.
In the first hours after calving, a newborn calf must be given colostrum to form strong immunity and develop its own microflora.
Of the vaccines and serums that are used for the treatment and prevention of colibacillosis in calves, the following drugs have proven themselves to be effective:
- polyvalent vaccine, which is used before and after calving;
- polyvalent whey – fed to calves according to age;
- coliprotectan VIEV – administered to the calf orally after birth once;
- bacteriophage – diluted with water and given to calves at the age of 1-4 months.
Only a veterinarian can determine the correct treatment regimen. In a farm where a sick animal is found, it is necessary to carry out all sanitary and veterinary measures. Sick calves are isolated from the herd to avoid mass infection.If infection is suspected, animals should be treated with bacteriophage or hyperimmune serum. When breeding cattle, you must comply with the standards of care and maintenance; at the slightest change in behavior, you must immediately contact a veterinarian to find out the reasons for this condition.
Conclusion
Colibacillosis in calves is quite difficult, since the first days of life are dangerous for animals. The infection manifests itself as severe dehydration, rapid exhaustion, intoxication of the body, and complications from the nervous system. Therefore, when the first symptoms of the disease appear, you need to invite a veterinarian and follow his instructions. You should not try to treat the animal yourself, as this disease threatens the life of the animal. It is better to prevent colibacillosis, so the owner needs to vaccinate animals in a timely manner and take care that the infection does not spread to the entire herd.
