Tuberculosis is a chronic contagious disease caused by a mycobacterium that affects many vertebrate animals, making their lungs and associated lymph nodes sick. Next we will make an approximation of how tuberculosis occurs in camelids.
The causative agent of this disease is Mycobacterium spp. The most important species of bacteria described in domestic animals are M. avium (in poultry, wild birds, pigs and horses), M. bovis (in ruminants) and M. tuberculosis (in humans, primates, dogs, companion birds and camelids).
In humans, tuberculosis remains one of the diseases that causes the most deaths, especially in less developed countries. In fact, It is one of the most important zoonoses, and in countries where milk is consumed fresh, unpasteurized is extremely common.
Epidemiology
Domestic animals act as a reservoir for wildlife and vice versa.And exotic animals, like camelids, are no exception. Living, for example, in a zoo or a reserve, they can come into contact with birds and small mammals that are infected.
In wild camelids it is less common than in those kept in flocks.
How is tuberculosis transmitted in camelids?
There are different ways for the infection to enter a healthy group. The most common is that an infected animal is introduced into the herd without adequate prior quarantine. Or because they maintain contact with other infected species, such as cattle.
Transmission occurs mainly via inhalation, by contact with drops of saliva from an infected animal.. In this case, the lesion will be pulmonary, and it is tremendously contagious. But in the digestive transmission by consumption of a contaminated food, the main affected are the lymph nodes of the intestine.
Source: Kaaden O, Wernery U. Infectious diseases of camelids. Bonston: Blackwell; 2002
Symptomatology
The typical lesion of this disease is the formation of granulomas (tubers) in the lung tissue and attached organs (pleura and lymph nodes).
The symptoms are of slow development, being a chronic disease. They range from discomfort and apathy, to febrile pneumonia with respiratory distress, cough, and bloody nasal and oral discharge.
Diagnosis of tuberculosis in camelids
The tests that exist in the veterinary clinic are not very useful with camelids, since they are adapted for use in domestic cattle. This is the case of intradermal tuberculin, which gives nonspecific results in these animals. But also from other tests based on blood tests.
The diagnosis is often intuitive, for the symptomatology, the contact with infected animals, or, directly, after the death of the animal, through the lesions seen in the necropsy.
Treatment and control
Tuberculosis control programs in other animals are based on periodic diagnostic tests. In the case of camelids we have already seen how these tests do not have the desired effect. In this way, The most effective control mechanism is the sacrifice of sick animals and suspected of being.
In zoos and reserves, when it comes to individuals who are valuable because of their genetics, there have been cases where treatment has been allowed, through antibiotics administered with feed.
In either case, it will be essential to clean and disinfect any material or surface in contact with the infected animal.