Content
Edema disease in piglets is the cause of the sudden death of vigorous and well-fed young pigs that “have everything.” The owner takes care of his piglets, provides them with all the necessary nutrition, but they die. It is unlikely that the fact that a similar disease under the same name also exists in lambs and kids will serve as a consolation here.
The causative agent of the disease
Scientists themselves have not yet come to a consensus on which microorganism causes edema disease in piglets. But most researchers “vote” that these are betahemolytic toxigenic colibacteria that cause specific poisoning of the body. Because of this, edematous disease received the name “enterotoxemia” (Morbus oedematosus porcellorum) in veterinary medicine. Sometimes the disease is also called paralytic toxicosis. But among the people, the name “edematous disease” has taken root.
Causes
The reasons for the development of enterotoxemia are no less mysterious than the true pathogen.If the causative agent of enterotoxemia is known to be one of the types of bacteria that constantly live in the intestines, then the cause is most likely a decrease in immunity.
But the trigger for a drop in the body’s resistance in piglets can be:
- stress resulting from weaning from the sow;
- premature weaning, when the intestines and protective systems of the body have not yet fully developed;
- poor content;
- lack of walking;
- poor quality feeding.
Even simply transferring a piglet from one pen to another can cause stress, which will lead to a decrease in immunity.
Active enterotoxemia bacteria can be introduced by a recovered piglet. The situation is the same as with human tuberculosis: all people have a certain amount of Koch bacilli in their lungs and on their skin. Bacteria do not cause harm as long as the body can defend itself or until a person with an open form of the disease appears nearby. That is, there will be a source of a large number of active bacteria nearby. In the case of edematous disease, such a “fountain” of active bacteria is a recovered piglet.
Who is at risk: piglets or pigs?
In fact, the entire population of pigs on the planet is carriers of colibacteria in quantities safe for the body. The disease is widespread throughout the world. But not everyone gets enterotoxemia. Well-fed and well-developed piglets are most susceptible to the disease, but only during certain periods of life:
- the most common cases are 10-14 days after weaning;
- second place for suckling piglets;
- on the third – young animals over 3 months old.
Adult pigs either have developed protective functions of the body, or have a hardened nervous system that does not allow the animal to become stressed over any little thing.
How dangerous is the disease?
Often the disease occurs suddenly and the owner does not have time to take action. The usual mortality rate for edematous disease is 80-100%. With the lightning form, 100% of piglets die. In chronic cases, up to 80% survive, but this form is recorded in “older” piglets with relatively strong immunity.
Pathogenesis
The reasons why pathogenic bacteria begin to multiply are still not reliably known. It is only assumed that due to disturbances in feeding and maintenance, colibacteria begin to actively multiply in the intestines. In the struggle for living space inside the piglet, toxigenic bacteria displace beneficial strains of E. coli. Dysbacteriosis occurs and metabolism is disrupted. Toxins begin to enter the body from the intestines. The amount of albumin in the blood decreases. This leads to the accumulation of water in the soft tissues, that is, to edema.
The development of enterotoxemia is also facilitated by a disturbance in the phosphorus-calcium balance: with an increase in the content of phosphorus and magnesium and a decrease in the amount of calcium, it leads to an increase in vascular permeability.
Symptoms
The incubation period lasts only a few hours: from 6 to 10. It is not clear, however, how this period was calculated if a piglet can get sick at any time and completely suddenly. The only version: they were infected in laboratory conditions.
But the latent period cannot be long either. It all depends on the rate of reproduction of bacteria, the number of which doubles per day already at a temperature of + 25 ° C.The temperature of a living pig is much higher, which means the rate of reproduction of microorganisms increases.
The very first sign of edema is a high temperature (40.5 °C). After 6-8 hours it drops to normal. It is difficult for a private owner to catch this moment, since people usually have other things to do. This is the main reason why edema occurs “suddenly.”
With the further development of enterotoxemia, other signs of the disease appear:
- swelling;
- unsteady gait;
- constipation or diarrhea;
- vomit;
- loss of appetite;
- photophobia;
- minor hemorrhages on the mucous membranes.
But the disease received its name “edematous” due to the accumulation of fluid in the subcutaneous tissue. When a piglet gets sick with enterotoxemia, the following swelling occurs:
- eyelids;
- forehead;
- back of the head;
- snout;
- intermaxillary space.
An attentive owner may already notice these symptoms.
Further development of the disease leads to damage to the nervous system. Piglets appear:
- muscle tremors;
- increased excitability;
- movement in a circle;
- head jerking;
- characteristic pose of a “sitting dog”;
- “running” while lying on your side;
- convulsions due to the most minor stimuli.
The arousal stage lasts only 30 minutes. After it comes a state of depression. The piglet no longer convulses over trifles. Instead, he stops responding to sounds and touch, experiencing severe depression. At the stage of depression, piglets develop paralysis and paresis of the legs. Shortly before death, bruises appear on the heel, ears, stomach and legs due to weakening cardiac activity.
In most cases, the death of piglets occurs 3-18 hours after the appearance of signs of edema. Sometimes they can last 2-3 days.Piglets older than 3 months are sick for 5-7 days. Piglets rarely recover, and those who have recovered lag behind in development.
Forms
Edema disease can occur in three forms: hyperacute, acute and chronic. Hyperacute is also often called lightning for the characteristic sudden death of piglets.
Lightning fast
With the fulminant form, a group of piglets that were perfectly healthy yesterday completely die within the next day. This form occurs in 2-month-old weaned piglets.
A hyperacute course is usually observed during an epizootic on a farm or in an agricultural complex. Simultaneously with the sudden death of piglets, stronger individuals “acquire” edema and damage to the central nervous system.
Acute
The most common form of the disease. Piglets live a little longer than with the fulminant form: from several hours to a day. The mortality rate is also slightly lower. Although all the piglets on the farm may die, in general the percentage of deaths as a result of edematous disease is 90 or more.
In a general description of symptoms, they focus on the acute form of the disease. Death in this form of disease occurs from asphyxia, since the affected nervous system no longer transmits signals from the respiratory center of the brain. The heart rate before death increases to 200 beats/minute. Trying to compensate the body for the lack of oxygen that has ceased to flow from the lungs, the heart accelerates the pumping of blood through the circulatory system.
Chronic
Piglets older than 3 months are affected. Characterized by:
- poor appetite;
- deposition;
- depressed state.
Difficulties in diagnosis
Symptoms of edema disease are very similar to other ailments of piglets:
- hypocalcemia;
- erysipelas;
- Aujeszky's disease;
- pasteurellosis;
- nervous form of plague;
- listeriosis;
- salt and feed poisoning.
Piglets with edematous disease cannot be distinguished from pigs with other diseases either in the photo or during a real examination. External signs are often the same, and a reliable diagnosis can only be made through pathological studies.
Pathanatomy
The main difference between edematous disease is that the piglets die in good condition. Suspicion of edematous disease arises if, during weaning, sudden cases of death of piglets with swelling of the abdominal organs and subcutaneous tissue soon appear. With diseases other than severe poisoning, they often manage to lose weight.
Upon examination, bluish spots on the skin are found:
- snout;
- ears;
- groin area;
- tail;
- legs
When autopsying a corpse, you can find swelling of the subcutaneous tissue on the limbs, head and abdomen. But not always.
But there are always changes in the stomach: swelling of the submucosa. Due to the swelling of the soft tissue layer, the wall of the stomach thickens greatly. The mucous membrane of the small intestines is swollen, with bruises. Fibrin threads are often found in intestinal loops. There is an accumulation of serous-hemorrhagic exudate in the abdominal and thoracic cavities.
Venous congestion is noted in the liver and kidneys. Due to tissue degeneration, the liver has an uneven color.
Lungs swollen. When cut, a foamy reddish liquid flows out of them.
The mesentery is edematous. Lymph nodes are enlarged and swollen. Red “bloody” areas in them alternate with pale anemic ones. The mesentery swells very much between the loops of the colon.Normally, the mesentery looks like a thin film that attaches the intestines to the dorsum of the animal. With edematous disease, it turns into a gelatinous liquid.
The vessels of the meninges are filled with blood. Sometimes hemorrhages are noticeable on them. There are no changes visible to the eye in the spinal cord.
The diagnosis is made on the basis of the clinical picture of the disease and changes in the body of dead piglets. Bacteriological research and data on the epizootic situation are also taken into account.
Treatment of edema disease in piglets
Since the disease is caused by bacteria and not viruses, it is quite treatable with antibiotics. Antibiotics of the penicillin and tetracycline groups can be used. At the same time, sulfonamide drugs are used.
As a concomitant therapy, a solution of calcium chloride 10% is used. It is administered by intravenous injections of 5 mg twice a day. For oral use, the dosage is 1 tbsp. l.
It is recommended to administer antihistamines:
- diphenhydramine;
- suprastina;
- diprazine.
The dosage, frequency and method of administration depend on the type of drug and its release form.
In case of heart failure, cordiamine is injected subcutaneously at 0.07 ml/kg twice a day. After recovery, the entire herd is given probiotics to restore intestinal flora.
During treatment, errors in feeding are also eliminated and a complete diet is calculated. During the first day of edematous disease, piglets are kept on a starvation diet.To cleanse the intestines as quickly as possible, they are given a laxative. On the second day, survivors are given easily digestible food:
- potato;
- beet;
- return;
- fresh grass.
Vitamin and mineral supplements are given according to feeding standards. Vitamins of groups B and D can be injected instead of fed.
Prevention measures
Prevention of edematous disease - first of all, proper housing and feeding conditions. The correct diet is necessary for pregnant pigs and, of course, lactating queens. Then the piglets are fed according to their age. Piglets begin to be fed vitamins and minerals very early, from the 3-5th day of life. In the warm season, piglets are released for walking. Avoid weaning too early. One-sided feeding of piglets with concentrates can also lead to edema. This diet should be avoided. At about 2 months of age, piglets are fed probiotics. The course of probiotics begins before weaning and ends after.
The premises, inventory, and equipment must be systematically cleaned and disinfected.
Vaccine
In Russia, the polyvaccine “Serdosan” is used against edematous disease in piglets. They vaccinate not just piglets, but the entire pig population. For preventive purposes, piglets are given the first vaccination on the 10-15th day of life. The piglets are vaccinated a second time after another 2 weeks. And the last time the vaccine is injected is 6 months later. after the second one. In case of an outbreak of edema disease on a farm, piglets are vaccinated for the third time after 3-4 months. Immunity against pathogenic strains of E. coli is developed half a month after the second vaccination.
But the vaccination scheme in this case changes: the second vaccination is given 7 days after the first; the third - a week and a half after the second.
Conclusion
Edema disease in piglets usually wipes out a farmer's entire litter, depriving him of profit. This can be avoided by following the rules of animal hygiene and preparing the diet correctly. General vaccination of all pigs will also prevent enterotoxemia from spreading.
