Characteristics and Control of Necrobacillosis in Deer

Necrobacillosis of deer is a chronic infectious disease caused by Necrobacillosis, which is usually caused by skin and mucosal wound infection. Necrosis is common in clinic, sometimes it can be transferred to liver, lung and other organs to form lesions, necrotic pneumonia and purulent hepatitis occur. If treatment is not timely, it often causes a large number of deaths. It is one of the most serious infectious diseases that harm@#@253@#@industry.

1 Pathogenic characteristics

Pathogen is necrobacter, mainly divided into A and AB type, gram stain negative, mostly long filiform, no flagella, can not move, do not form spores. Necrobacter is known to produce at least two toxins that cause tissue edema, necrosis, and hemolysis. Necrobacter is strictly anaerobic and widely exists in nature and animal intestines, especially in feedlots. Necrobacilli resistance is not strong, heated to 100℃ about 1 minute can be killed, with 2.5% formalin, 6% lysol 10~15 minutes can also be killed.

2 Epidemic characteristics

Necrobacillosis of deer can occur all year round, but it is more common in summer and autumn. Deer of all ages can be infected. Skin injury is the main route of infection, but it can also be infected through digestive tract trauma, sawn antler injury, birth canal and umbilical wound. In addition, wet ground, sultry climate, poor management of breeding, etc. will promote the occurrence of necrobacillosis.

3 Clinical features

The deer suffered from lethargy, loss of appetite, emaciation and lying on the ground. Clinical common lesions mainly occur in the limbs, especially the hoof, manifested as suppuration, ulcer and necrosis. Local abscess first formed, followed by necrosis, necrosis focus center depression, rupture after the outflow of pus and blood, severe hoof crown swelling in the outflow of millet rice soup like foul pus, necrotic tissue mostly gray-black or green, mixed with gray-white pus, there is a special foul smell. After hoof erosion gangrene, pathological changes can spread upward to subcutaneous tissue of limbs, resulting in swelling and necrosis of palms and even joints, and fistula can be formed in serious cases. Severe cases of hoof cartilage, joint and ligament necrosis, hoof shell off, hoof serious deformation, become "big-footed deer." If the lesion metastasizes to the internal organs, it often leads to death.

Most of the fawns born in rainy seasons were infected from the umbilicus and caused necrobacillosis. After the onset, the young deer showed urination bow waist, mental fatigue, hair disheveled. Careful examination of the umbilical, can be found in a cord-shaped induration, serious fist size, from the umbilical outflow of gray odor rice soup-like pus.

4 Anatomical characteristics

Necrobacter dead deer carcass emaciated, limbs necrosis focus obvious, other parts have different degrees of necrosis focus, the affected part of the vein was purple-black. Pleural effusion, smelly smell, containing grayish yellow cellulose-like exudate. Pericardial effusion, opacity, fibrinoid exudate on pericardium and myocardium. Pathological changes of necrotizing pneumonia were present in the lungs. Liver enlargement with necrotic lesions of varying sizes. There were necrotic foci of different sizes in the anterior gastric mucosa and extensive inflammation in the peritoneum.

5 Treatments

For deer necrobacillosis, local treatment and systemic treatment must be combined in clinical practice to obtain ideal curative effect.

5.1 local therapy

External wounds can be washed with 3% hydrogen peroxide to drain pus and, if necessary, to initiate treatment. After cleaning the wound, iodoform sulfanilamide powder (iodoform 1 part, sulfanilamide powder 9 parts) was spread on the surface of the wound, and iodoform ichthyst ointment (iodoform 10 parts, ichthyst 15 parts, vaseline 75 parts) or iodoform cod liver oil ointment (iodoform powder mixed with cod liver oil) was coated on the outside. Bandage the wound and change dressing once every 1~2 days. Severe cases can be treated with 0.25% procaine 20mL, iodoamine injection 20mL, streptomycin 100 international units for limb and foot closure.

5.2 systemic therapy

Antibiotics and sulfa drugs can be selected. Tetracycline and aureomycin were injected intramuscularly or intravenously at a dose of 5 - 10mg per kilogram of body weight twice a day. Erythromycin is administered intravenously twice a day at a dose of 2 - 4mg/kg body weight dissolved in 5% glucose injection. Compound clarithromycin injection, 0.1 mL/kg body weight, intramuscular or intravenous, once every 12 hours. 10% sulfadiazine sodium 100~150mg, intravenous, twice a day. Streptomycin 3 million IU and penicillin 4 million IU can also be injected intramuscularly twice daily. It is necessary to continuously use the drug for 1 week to obtain the ideal effect.

For the sick deer with loss of appetite, taking Gentiana root, rhubarb root, ginger tincture and other stomachic agents can promote appetite, improve disease resistance and promote early recovery of the body.

6 The precautionary principle

6.1 Do a good job of disinfection

Attention should be paid to regular disinfection and irregular disinfection to keep the house clean and hygienic. Disinfectants can be selected from 3% bleaching powder solution, 3% lysol, 10%~20% fresh lime milk, etc. The umbilical cords of newborn deer were disinfected with 5% iodine tincture. Disinfection should also be noted when sawing antler. Disinfection treatment must be carried out in time if skin damage is found on limbs. Let deer more sun exposure, can also play a role in sterilization.

6.2 kept dry

At ordinary times, management should be strengthened, feces should be cleaned up in time, dry cushion soil and bedding should be laid, and deer houses should be kept dry and clean. Rain season should pay attention to check the roof, timely discharge ponding, prevent accumulation of rainwater in the enclosure.

6.3 adequate nutrition

It has been proved that deficiency of calcium, phosphorus and vitamins can induce necrobacillosis in deer. Therefore, be sure to let deer eat enough calcium, phosphorus and other minerals and multivitamins. After 10~15 days of age, rumen begins to play a role, and a small amount of feed should be taken, and attention should be paid to supplementing green feed, especially high quality green feed rich in calcium and phosphorus.

6.4 rational weaning

Young deer in weaning period are most susceptible to necrobacillosis. Therefore, nutrition regulation must be strengthened, Vc, VE and other substances with antioxidant and anti-stress effects should be appropriately added, and complete diets should be fed to achieve diversification, good palatability and easy digestion of feeds. Pay attention to the transition between feed and environment, do not drive or whip deer, and minimize or avoid various adverse stimuli.

6.5 prevent harm

Keep the floor of pens and sports grounds flat and do not feed with sharp burrs. Be careful when grouping or adjusting groups to prevent treading and bruising. Strengthen the management of deer herd in breeding season to prevent deer herd damage caused by fighting. Do not graze in thorny and uneven places. Pay attention to check whether there are protruding wood thorns and nails in the trough, wooden piles, etc., and check whether there are sharp foreign bodies on the edge of the drinking fountain. It is strictly prohibited for outsiders to visit the circle to prevent disturbing deer herd and causing panic.

6.6 attention to isolation

Deer are the main source of infection. Therefore, deer infestation was found. Disease, to timely isolation treatment, at the same time do a good job of disinfection work. The newly transferred deer shall be quarantined before admission. If sick deer are found, they shall be isolated and raised immediately. The utensils in the isolation circle shall not be shared with the healthy circle.

6.7 Make a foot bath.

The establishment of foot bath can not only prevent the disease, but also have a good auxiliary treatment effect for deer with pathological changes in their hooves. The method is as follows: the drinking place is set into a dead end, a disinfection pool with the length of 2m and the width of the alley is built at the entrance and exit, 1% lysol water is put into the pool, 10% copper sulfate solution or 3% potassium permanganate solution can also be used, and the liquid medicine is kept at a depth of about 30cm. The deer is required to stand in the disinfection pool when drinking water, so that the hoof can be soaked and disinfected for a long time when drinking water. It should be noted that the liquid medicine must be added in time, and there must be enough water in the drinking water container.