Content
Bovine necrobacteriosis is a fairly common disease in all regions and regions of the Russian Federation, where livestock is engaged. Pathology causes serious economic damage to farms, since during the period of illness, cattle lose milk production and up to 40% of their body weight. Farm animals and humans are susceptible to necrobacteriosis. The disease is recorded most often in breeding, fattening farms and is characterized by lesions of the limbs. The main cause of this disease in cattle is violation of veterinary, sanitary and technological standards. It can proceed in acute, chronic and subacute form.
What is necrobacteriosis
Examination of the mucous membrane of the mouth of cattle
Cattle necrobacteriosis has another name - cattle panaritium. The disease is infectious, characterized by purulent lesions and necrosis of areas in the hoof, interdigital fissure, and corolla. Sometimes the udder, genitals, lungs and liver are affected. In young individuals, necrosis of the mucous membranes in the mouth is often observed.
In the absence of proper therapy and a weak immune system of the animal, the disease turns into a more serious form within a few weeks. Bacteria multiply quite quickly, penetrating into internal organs and tissues, causing severe intoxication in the body of cattle.
Necrobacteriosis of cattle began to actively spread on farms in the early 70s after a large batch of breeding animals entered the territory of the former USSR. Until today, veterinarians are doing everything possible to prevent the disease from spreading so actively. Extremity infections are considered to be the biggest threat to dairy farms, as only a healthy cow can yield high milk production. This requires good, strong limbs to actively move. With pain in the legs, individuals eat less, move around, thus, milk production is significantly reduced.
The causative agent of necrobacteriosis in cattle
The causative agent of cattle necrobacteriosis is an immobile toxin-forming anaerobic microorganism. A comfortable habitat for him is the digestive tract of livestock. Upon contact with oxygen, it instantly dies. In the affected tissues and organs, the bacterium forms long colonies; solitary microorganisms are less common.
The causative agent of necrobacteriosis in cattle
The pathogen is divided into 4 types, of which the most pathogenic are serotypes A and AB. In the process of life, they form toxic compounds that are involved in the development of the disease. The bacterium dies, losing its pathogenic effect:
- during boiling for 1 minute;
- under the influence of sunlight - 10 hours;
- under the influence of chlorine - half an hour;
- on contact with formalin, alcohol (70%) - 10 minutes;
- from caustic soda - after 15 minutes.
Also, the necrobacteriosis bacterium is sensitive to antiseptics such as lysol, creolin, phenol, drugs from the tetracyclines group. For a long time, the pathogen is able to remain viable (up to 2 months) in the ground, manure. In moisture, the bacterium lives up to 2-3 weeks.
Sources and routes of infection
The causative agent of cattle infection enters the environment with various secretions of individuals - feces, urine, milk, mucus from the genitals. Infection occurs by contact. Microorganisms enter the body of cattle through the wound surface on the skin or mucous membranes. The danger is caused by individuals with a pronounced clinical picture of the disease and recovered animals.
Usually, the disease is recorded on the farm after the delivery of a batch of livestock from a dysfunctional farm, without observing a 30-day quarantine. Further, necrobacteriosis is periodic in nature with an exacerbation in the autumn-spring season, especially if feeding and conditions of detention deteriorate. In addition, the following factors have a great influence on the development of the disease:
- untimely cleaning of manure;
- poor quality floor in the barn;
- lack of hoof trimming;
- high humidity;
- skin parasites and other insects;
- trauma, injury;
- decreased body resistance;
- walking in wetlands;
- lack of veterinary, zootechnical measures on farms and farms.
In the body of cattle, the infection spreads with the blood flow, so secondary areas of damage are formed in the tissues, and necrosis develops in the heart, liver, lungs, and other organs. As soon as the disease passes into this form, the prognosis becomes more unfavorable.
Symptoms of cattle necrobacteriosis
It is difficult to recognize the manifestations of the disease without an examination by a veterinarian, because the symptoms of necrobacteriosis in the body of cattle are also characteristic of a number of other pathologies.
The defeat of the limbs of cattle by necrobacteriosis
Common symptoms of infection include:
- lack of appetite;
- depressed state;
- low productivity;
- limitation of mobility;
- loss of body weight;
- foci of purulent lesions of the skin, mucous membranes, limbs of cattle.
With necrobacteriosis of the extremities (photo), a cattle individual picks up legs under him, limps. Examination of the hooves shows swelling, redness, and purulent discharge. At the first stage of the disease, necrosis has clear boundaries, then the lesions expand, fistulas and ulcers are formed. Severe pain occurs on palpation.
The skin is most often affected in the neck, limbs above the hooves, genitals. It manifests itself in the form of ulcerations and abscesses.
With the development of necrobacteriosis in cattle, the mouth, nose, tongue, gums, larynx suffer on the mucous membranes. On examination, foci of necrosis, ulcers are visible. Infected individuals have increased salivation.
Necrobacteriosis of the udder of cattle is characterized by the appearance of signs of purulent mastitis.
With necrobacteriosis of cattle, necrotic formations appear in the stomach, lungs, and liver from the internal organs. This form of the disease is the most severe. The prognosis of the disease is unfavorable. The animal dies after a couple of weeks from exhaustion of the body.
Necrobacteriosis proceeds differently in mature cattle and young animals. In adult animals, the incubation period can last up to 5 days, and then the disease becomes chronic. In this case, the infection is difficult to treat.Sometimes bacteria begin to spread through the lymphatic system, resulting in gangrene or pneumonia.
The incubation period in young individuals lasts no more than 3 days, after which the pathology becomes acute. Young animals have severe diarrhea, which leads to rapid dehydration. As a rule, the cause of death is blood poisoning or wasting.
Vaccination of cattle against necrobacteriosis
Diagnosis of necrobacteriosis in cattle
Diagnostics is carried out in a comprehensive manner, taking into account epizootological data, clinical manifestations, pathological changes, as well as with the help of laboratory studies according to the instructions for cattle necrobacteriosis. The diagnosis can be considered accurate in several cases:
- If, when laboratory animals are infected, they develop necrotic foci at the injection site, as a result of which they die. The culture of the pathogen is found in smears.
- When determining a culture from pathological material with subsequent infection of laboratory animals.
When conducting differential analysis, it is important not to confuse the infection with diseases such as brucellosis, plague, pneumonia, tuberculosis, foot and mouth disease, aphthous stomatitis, purulent endometritis. These pathologies have similar clinical manifestations with necrobacteriosis. In addition, veterinarians should exclude laminitis, dermatitis, erosion, ulcers and hoof injuries, arthritis.
After the animals recovered, the development of immunity to necrobacteriosis in cattle was not revealed. For immunization, a polyvalent vaccine against cattle necrobacteriosis is used.
All types of laboratory research are carried out in several stages. Initially, scrapings are taken from infected tissues, mucous membranes. In addition, urine, saliva, and smears from the genitals are collected.
The next step will be the isolation and identification of the causative agent of necrobacteriosis. The final stage involves some research on laboratory animals.
Pathological changes in dead individuals with necrobacteriosis of the limbs in cattle suggest purulent arthritis, accumulation of exudate in muscle spaces, tendovaginitis, abscesses of various sizes, phlegmonous formations, foci of necrosis in the femoral muscles. With necrobacteriosis of organs, abscesses containing a purulent mass, necrosis are found. Pneumonia of a purulent-necrotic nature, pleurisy, pericarditis, peritonitis are noted.
Necrobacteriosis of the skin of cattle
Treatment of necrobacteriosis of cattle
Immediately after the diagnosis of necrobacteriosis, treatment should be started. First of all, the infected animal must be isolated in a separate room, dry cleaning the affected areas with the removal of dead tissue. Wash the wounds with a solution of hydrogen peroxide, furacillin or other means.
Since the bacterium creates a kind of barrier between the vessels and the infected tissues, the penetration of drugs is very difficult. That is why antibiotics for the treatment of necrobacteriosis in cattle are prescribed in somewhat overestimated dosages. The most effective drugs include:
- erythromycin;
- penicillin;
- ampicillin;
- chloramphenicol.
Topical antibacterial agents such as aerosol antibiotics have shown beneficial effects. They are used after dry cleaning of hooves.
Group therapy based on regular foot baths is widely used. The containers are installed in those places where the animal most often moves. The bath contains disinfectants.
The treatment regimen for necrobacteriosis in cattle is made by a veterinarian, based on the research carried out. Further, he can change therapeutic measures depending on changes in the condition of sick cattle.
Since necrobacteriosis of cattle is a contagious disease for humans, it is necessary to exclude the slightest possibility of infection. To do this, farm employees need to know and follow basic rules of personal hygiene, use overalls and gloves while working on the farm. Skin wounds should be treated with antiseptic agents in a timely manner.
Preventive actions
Treatment of cattle hooves
Treatment and prevention of necrobacteriosis of cattle should also include the improvement of the entire economy, where the disease was detected. You must enter quarantine mode on the farm. During this period, you cannot import and export any livestock. All changes in the maintenance, care, nutrition must be agreed with the veterinarian. Sick cows with suspected necrobacteriosis are isolated from healthy cows, a treatment regimen is prescribed, the rest are vaccinated. All livestock once every 7-10 days must be driven through special corridors with disinfectant solutions in containers.
For the slaughter of cattle, it is necessary to prepare special sanitary slaughterhouses and obtain permission from the veterinary service. Cow carcasses are burned, you can also process them into flour. Milk is allowed to be used only after pasteurization. Quarantine is lifted a few months after the last infected animal is cured or slaughtered.
General preventive measures include the following:
- the herd needs to be completed with healthy individuals from prosperous farms;
- arriving cows are quarantined for a month;
- before introducing new individuals into the herd, they must be driven through a corridor with a disinfectant solution;
- daily cleaning of the barn;
- disinfection of the premises once every 3 months;
- hoof processing 2 times a year;
- timely vaccination;
- balanced diet;
- vitamin supplements and minerals;
- regular examination of animals for injuries.
Also, to prevent the development of necrobacteriosis, the maintenance of animals should be normalized. Premises must be removed from manure in a timely manner, flooring must be changed to avoid injury.
Conclusion
Bovine necrobacteriosis is a complex systemic disease of an infectious nature. The risk group includes, first of all, young cattle. In the initial stages of the disease, with a competent treatment regimen drawn up by a veterinarian, the prognosis is favorable. Necrobacteriosis is successfully avoided by farms actively involved in prevention.
