Salmonellosis in calves: vaccine against the disease, treatment and prevention

Salmonellosis in calves is a widespread disease that almost all farms face sooner or later. Basically, the disease affects young animals up to two months old, since adults have higher resistance to various infections. The danger of salmonellosis lies in the fact that it can be transmitted not only to other animals, but also to humans.

What is salmonellosis

Salmonellosis is an infectious disease that can affect many species of animals and birds. The disease is caused by Salmonella bacteria, microorganisms that are resistant to adverse environmental conditions, so even equipment for working with animals can cause a second outbreak of infection. Also, rooms where sick calves were kept may remain infected for a long time.

The peak period of the disease occurs in the spring – the time of mass calving, but in general, salmonellosis can develop in cattle at any time of the year. Very vulnerable to this disease are small calves, especially newborns. Symptoms of salmonellosis can appear in them as early as 10 days after birth. The higher the unsanitary conditions for keeping cattle, the greater the likelihood of an outbreak of salmonellosis in the herd.

Pathogenesis of salmonellosis

Carriers of salmonellosis are rodents and adult cows, in which the disease is most often asymptomatic. The infection is usually transmitted to small calves through milk or contaminated equipment, however, the conditions of the barn play an equally important role. If the room is rarely cleaned, the likelihood of developing salmonellosis is increased, as it can be transmitted through the urine and feces of cattle. First of all, the infection affects individuals with a weakened immune system – calves that have recently been ill with something, or animals that are deficient in vitamins. In the latter case, cows receive poor-quality or extremely monotonous feed.

Symptoms of salmonellosis may appear the next day after infection or two weeks later. The disease proceeds in a mild, acute and chronic form, however, their symptoms are largely similar.

Salmonellosis causes weakness and apathy in affected animals

Symptoms of salmonellosis in calves

Signs that calves are affected by salmonellosis can be the following changes in the behavior and physiology of animals:

1. They become lethargic and lethargic, sleeping or just lying down almost all the time.
2. Clear mucus is profusely discharged from the nose.
3. Animals stop eating or eat very little.
4. Sometimes 2-3 days after infection in sick calves, a change in stool is noted – it becomes liquid and frequent, diarrhea begins. There is gray mucus and blood in the stool.
5. The acute course of salmonellosis is characterized by high temperature – it can increase up to 40-42°C.
6. If the disease is severe, calves experience frequent urination. The process becomes painful, there is blood in the urine.
7. In the acute form of salmonellosis in sick animals, cough, runny nose and conjunctivitis are additionally noted. If the infection is delayed, the calves may develop a fever.

The chronic form of salmonellosis develops if the disease was not detected on time or simply started treatment too late. It is characterized by the same symptoms, but arthritis and respiratory diseases develop additionally. Diarrhea disappears over time, appetite returns to sick individuals for a short time, however, weight loss is noted.

In time, the chronic form can stretch up to two months.

Diagnosis of salmonellosis

Diagnosis of salmonellosis in calves is complicated by the fact that the characteristic signs of infection are similar to the symptoms of other diseases:

• colibacillosis (the age of the cubs is less than 10 days, there is sepsis and serous inflammation of the lymph nodes);
• pasteurellosis (croupous pneumonia is present);
• dyspepsia (the age of calves is less than 10 days, sepsis is not observed);
• streptococcal infection (diagnose pericarditis, pleurisy).

Diagnosis is made after a comprehensive examination of calves. To do this, it is necessary to send blood and feces taken from sick animals to the laboratory.

Treatment of salmonellosis in cattle

The first thing to do after detecting salmonellosis in calves is to separate the sick individual from the rest of the herd in order to prevent the spread of the disease. After that, they begin complex treatment with the use of antibiotics and auxiliary drugs. Most often, a veterinarian with salmonellosis prescribes the following remedies:

1. Levomycetin veterinary in tablets for oral administration. The exact dosage is calculated by the veterinarian, taking into account the weight of the calf. The recommended course of the drug is 3-4 days with a frequency of use three times a day.
   
   

   “Levomitsetin” is represented by different forms of release, however, for the treatment of cattle, a veterinary version is used in tablets

2. “Terramycin”. The course of treatment lasts approximately 5-6 days, for each kilogram of the animal’s weight, 0,02 g of the drug falls. The frequency of use is 2-3 times a day.
   
   

   “Terramycin” is produced in the form of an aerosol and solution

3. Polyvalent antitoxic serum. The action of the drug is aimed at strengthening the immune system and preventing the disease in calves and adult cows. Serum is administered intramuscularly, the doctor calculates the dose. It is recommended to divide the daily rate into several injections, between which they usually take a break of 3-5 hours.
   
   

   All injections are carried out using disposable syringes that are not allowed to be reused.

Expired products should not be used to treat salmonellosis in calves. They can harm the health of animals.

Salmonellosis vaccine in calves

The salmonellosis vaccine is the most effective protection against this disease. It is recommended to vaccinate calves 1-2 days after birth. The vaccine will not help already infected individuals, but in healthy animals, a general strengthening of immunity is noted.

The drug begins to act on average on the 14th day. 10 days after the first vaccination, a second is usually given. Adult cows are vaccinated a month and a half before calving. In this case, a newborn calf is vaccinated only once and a little later – 15-20 days after birth.

If the veterinarian diagnoses any ailment in the young, vaccination should be delayed a little.

Pathological changes in salmonellosis in calves

The acute course of the disease can affect the organs of the gastrointestinal tract, as a result of which gastroenteritis and sepsis are diagnosed in calves. In chronic salmonellosis in sick individuals, the respiratory tract, digestive organs and immune system are affected. Acute catarrhal inflammation begins in the rectum and small intestine of affected calves.

At two months of age, exudative inflammation may develop in animals. The liver of calves is enlarged, necrosis and salmonella nodules are formed in it.

Preventive measures

Salmonellosis can quickly spread to most of the herd if not treated promptly. However, it is even better to avoid an outbreak of the disease at all – for this it is enough to follow the most basic rules for keeping cattle:

1. The cowshed should be cleaned at least once a week. At the same time, it is not enough just to remove the dirt – it is also desirable to use various disinfectants. After each bowel movement, the floor in the room where an adult animal or calf is kept must be washed.
2. In no case should cattle be kept in cramped conditions. If the animals crowd close to each other in a small room, the spread of salmonellosis occurs very quickly. In addition, with this content, it is necessary to clean the barn much more often.
3. A quick inspection of the entire herd is recommended every day. This increases the chances of noticing the first symptoms of salmonellosis in time and starting timely treatment before the disease has passed to other animals.
4. It is very important to regularly take cows and calves for a walk. In the barn itself, it is necessary to install good air ventilation.
5. So that rodents, which are also carriers of infection, do not start in the room, after each feeding, food remains are removed. You cannot store food in bags in the same room.
6. Drinking water for calves should be at room temperature. It is changed regularly – dirty drinkers often become sources of infection.

The risk of disease is lower if cattle are kept in a sufficiently spacious room

In farms that are unfavorable for salmonellosis, it is recommended to vaccinate pregnant cows. To do this, they are administered the formol-alum vaccine against calf paratyphoid twice with a break of two months.

Good nutrition is also of great importance for the health of cattle. The lack of certain substances in the body of animals weakens their immunity, as a result of which they are not able to resist the disease. In the summer, calves should receive a sufficient amount of fresh food; they should not be fed with rotten and rotten hay. With the onset of frost, the herd is released for walking carefully, as the grass already has time to freeze. From time to time, calves need to be given vitamin supplements.

Conclusion

Salmonellosis in calves is a rather dangerous infectious disease, but with timely treatment, animals recover quickly. After an outbreak of infection, it is necessary to thoroughly disinfect all equipment that was used to work with calves, and the room where the sick individuals were located. In the process of treatment, it is also important to provide for your own safety – salmonellosis can be transmitted to humans.

You can learn more about the symptoms, the course of the disease and its treatment from the video below: