GENERAL INFORMATION ABOUT ENTEROTOXEMIA

Enteroxemia is a repeatable disease in sheep and goats of all ages. The bacteria that cause this disease are present in a relatively small number in the animal’s digestive system and in a healthy and normal animal, they are relatively unobservable. The disease occurs when the number of these bacteria increases due to a change in diet and the deadly toxins secreted by these bacteria.
Therefore, the probability of being successful in preventing enterotoxemia is much higher than trying to treat the disease.
Enterotoxemia is a common disease of sheep and goats of all ages caused by two strains of Clostridium perfringens bacteria (type C and D). These bacteria are usually found in small numbers in the digestive system of sheep and goats and may be called the microbial flora of the animal. Therefore, the question arises, if so, when and why does it cause disease in the animal?
These bacteria are normally found in the small and large intestines and are not active in a normal state, but it seems that a change in the animal’s diet and an increase in carbohydrates causes the disease to start. Usually, the change that causes the disease is an increase in the amount of grain, protein supplement, milk or milk replacer (for lambs), or grass that the sheep or goat eats primarily in the spring. In general, compounds rich in starch, simple sugars and protein can stimulate rapid growth and toxin production in bacteria.
When an abnormally high percentage of these nutrients reaches the digestive system and intestines, Clostridium perfringens grows explosively (which sometimes takes up to 5 minutes for doubling time) and their numbers increase in the intestines in less than 3-5 hours. With the increase in the number of bacteria and the expression of genes and the decrease in pH, a large amount of toxin is secreted by the bacteria with great destructive power and causes internal bleeding and damage to the organs in the animal. The high volume of toxins and their intense activity in the absence of sufficient antitoxin (antibodies against toxins) in the blood lead to casualties. This damage is more severe in non-vaccinated animals or lambs, and the best way for inhibition of this damage is vaccination.
The symptoms of enterotoxemia in sheep and goats can be as follows:

• The animal may suddenly stop eating and become lethargic.

• A sick animal with symptoms of stomach pain, kicking in the stomach, lying down and getting up frequently, lying on its side, panting and sometimes even crying because of the pain.

• In some cases, diarrhea with blood can also be seen.

• Sometimes the animal loses the ability to stand, lie on its side, and stretch its legs and pull its head and neck back. This condition is caused by the effect of toxin on the brain and nervous system.

• Due to the high toxicity of toxins secreted in the animal’s body, death usually occurs within a few minutes to a few hours after observing the above symptoms.

• Due to the rapid progress of enterotoxemia in the body, sometimes the animal may die without any previous symptoms of the disease.

TREATMENT

Treatment of enterotoxemia may not be successful in acute cases. Various solutions can be used to treat the patient (in a mild case) at the time of observation, including the use of painkillers, probiotics, oral electrolyte solutions, and antisera. But for more severe cases, intravenous fluids, antibiotic therapy and other types of supportive care such as supplemental oxygen, etc. may be needed.

PREVENTION

Prevention of enterotoxemia by vaccination or planned feeding is much more successful than trying to treat this disease.

VACCINATION

Perhaps one of the oldest scientific articles for livestock vaccination against enterotoxemia (Clostridium) is by Muth and Muriel in 1946. But this disease has a very long history with human life. Vaccination is perhaps the only way to prevent this disease. For sheep and goats, there are several vaccines that provide immunity against toxins produced by Clostridium species. These vaccines can include from two to several types of pathogens. But almost all vaccines require two injections (two doses) to create effective immunity, usually with an interval of 10 to 14 days. Vaccination of adult sheep or goats when they receive two doses can create a stable immune condition and revaccination plan should be done at least once a year.
In scientific sources or the experience of veterinarians, it has been shown that vaccination of ewes approximately one to two months before the expected birth date increases the antibody in the colostrum milk (first milk) and this helps to protect lambs or goats against enterotoxemia. Recommendation: It is suggested that if it is not possible to immunize pregnant animals in the stated time frame, it is better to vaccinate ewes at other times and with an interval of every six months in a year.
It should be mentioned that for young and adult sheep and goats that are fed with a diet rich in cereals or in green pastures and use fresh fodder, it is better to use frequent vaccination for enterotoxemia. Some producers vaccinate these animals two to four times a year to ensure adequate immunity.
Keeping ewes and mothers safe is the best way to protect newborn lambs and goats against this disease, because the antibodies to the toxins of these bacteria are transferred to the babies in colostrum milk.
Young and growing animals are usually vaccinated for the first time at 6 to 10 weeks of age, and one or two vaccinations (boosters) are given.

Malignant edema in animals (gas gangrene)

Clostridium septicum is a Clostridium species that is usually associated with malignant edema. Malignant edema or gas gangrene is an acute and often fatal bacterial disease caused by Clostridium species. C septicum also causes bruxism in sheep, a highly fatal infection characterized by the presence of toxin and inflammation of the udder wall. Infection generally occurs through wound contamination and clinical symptoms develop within 2 days. Among the systemic symptoms (such as fever) and local swelling in the muscles and intermuscular connective tissues, and in the affected area, it contains gas accumulations that can be felt in the subcutaneous tissue around the infected area. Skin color change and fever along with anorexia, severe depression and possibly hyperthermic can be seen in the animal. In acute cases, death occurs within 12 hours to 2 days.
Potent Clostridial toxins cause local and systemic symptoms, often leading to death. Topical exotoxins cause excessive inflammation, resulting in severe edema, necrosis, and gangrene. Different types of wounds, childbirth in sheep and traumatic birth and castration in cows and horses can be a suitable place for the growth of bacteria in anaerobic and aerobic conditions.
It also causes bruxism in sheep, a very fatal infection characterized by toxins and inflammation of the udder wall. The disease appears to be mostly confined to European sheep fed on “frozen” pastures.
The diagnosis can be confirmed rapidly based on C. septicum fluorescent antibody staining of a tissue smear. However, C. septicum is a very active postmortem invader of the gut, and its presence is not significant in a sample taken from an animal that has been dead for more than 24 hours.
Immunohistochemical test has also been used to identify bacteria. PCR method can be used for direct identification and differentiation of clostridia associated with malignant edema. The presence of type III echinocytes or spherocytes in blood smears may help diagnose immune-mediated hemolytic anemia associated with Clostridial infections. Fine-needle aspiration and gram staining may confirm the presence of gram-positive rods prior to confirmation by anaerobic culture.

Prevention and control

The best way to control this disease is to use multivalent Clostridial vaccines that contain alpha toxoid of this bacterium.

Briefly:

• Malignant edema is an acute and generally fatal toxemia that can affect all animal species and ages and is mainly caused by Clostridium septicum.

• The infection can occur through the contamination of wounds, soil in contact with the wound or through the activation of bacterial spores that are present in everyone.

• Proper carcass disposal and vaccination can prevent the spread of bacteria and disease in other animals.

Infectious Necrotic Hepatitis in Animals

(Clostridium novyi Infection, Black Disease)

Clostridium novyi, an anaerobic, motile, spore-forming, gram-positive bacterium, is the cause of gangrene. Infectious necrotizing hepatitis (INH) is caused by Clostridium novyi type B. This bacterium is found naturally in soil and feces and provides its energy from the metabolism of food and the production of fatty acids and organic substances, which causes the production of a pungent and inappropriate smell from the growth of bacteria. The production of alpha toxin of this bacterium, which has lethality and specific function on cell signals, increases when the bacterium is in anaerobic conditions and causes gangrene in muscles. This disease is common in sheep, but it is also seen in cattle and goats, where it is called (black disease) due to the dark color change of the subcutaneous tissue caused by severe venous congestion in the carcasses of animals that die due to this disease.

Prevention and control

The best way to control and prevent this disease, like the previous cases, is to use a vaccine containing Clostridium novyi alpha toxoid.