Distribution and Prevention Strategies of Paratuberculosis in Dairy Cattle in Burdur Province

PROJECT NAME: Distribution and Prevention Strategies of Paratuberculosis in Dairy Cattle in Burdur Province
PROJECT LEADER: Prof. Dr. Dilek ÖZTÜRK
PROJECT TOPIC:
Paratuberculosis is a chronic infectious disease characterized by granulomatous inflammation of the intestines and regional lymph nodes in ruminants caused by Mycobacterium avium subspecies paratuberculosis (MAP). It causes chronic diarrhea in ruminants. In recent years, its importance in terms of public health is due to the consideration that this agent, which widely infects ruminants, can be transmitted to humans through directly contaminated milk and dairy products, thus making the disease zoonotic in nature.  

Paratuberculosis (pTB) progresses subclinically for a long time in infected cattle. The agent cannot be detected in fecal samples of many cattle before the age of two. During this phase, the transmission of the agent to healthy animals in the herd by infected cattle continues. In this early stage of infection, no clinical symptoms are observed in ruminants. As the disease progresses, MAP spreads to regional lymph nodes and clinical symptoms appear. Typical findings are chronic diarrhea and weight loss, and pTB is also one of the most important diseases causing economic losses in dairy cattle enterprises.

The microbiological diagnostic method of pTB, which is isolation and identification is the gold standard. However, the very slow and difficult growth of the bacterium under in vitro conditions, considering the time, labor, and costs, has necessitated the use of alternative diagnostic techniques. Therefore, molecular diagnostic methods are preferred today. Among these methods, molecular diagnostic techniques involving polymerase chain reaction (PCR) and PCR-based techniques are utilized. ELISA is a serological test that allows the detection of antibodies against MAP. It is the most commonly used method in the field for diagnosing this disease today. It is a rapid and extremely easy-to-apply test for sample analysis.

With this study; it is aimed to conduct screenings with culture, conventional PCR, and ELISA, a serological method, to create herds free from Mycobacterium avium subsp. paratuberculosis in dairy cattle enterprises in Burdur province, which has a high livestock potential. After removing positive animals from the herd, if animals test negative for two consecutive years, the enterprises will be given a certificate of being free from pTB. The project, with its purpose and potential, has the characteristic of making significant contributions to both the national economy, public health, and thus societal welfare, as well as scientific knowledge. 

PROJECT PURPOSE:
It is known that pTB was first diagnosed in cattle in Turkey by Sezginer in 1928 and its pathology was examined by Akçay and Erbil in 1932. Studies show that the disease is still a problem in cattle, sheep, and goat enterprises.

Within the scope of the project;

•    Control and eradication programs for pTB are implemented in many countries around the world, and positive results are reported. There is no vaccine for paratuberculosis disease in Turkey. Moreover, it is not a notifiable disease. Therefore, it is a disease that is overlooked in enterprises. Although studies are being conducted to reveal its prevalence in our country, the exact status of this disease is not known. There is no control and eradication study for paratuberculosis disease in our country. With this study, the status of the disease will first be determined in a dairy cattle enterprise, and if the prevalence is low, the animals will be sent slaughtered. Subsequently, tests will be conducted every 6 months to monitor the disease. In enterprises where the disease is not observed within 2 years, a certificate of being free from paratuberculosis will be given.

•    This study will primarily aim to create awareness about paratuberculosis disease by providing training. In this context, employees and owners of the enterprises where the study will be implemented will first be informed about paratuberculosis disease, its transmission routes, and the necessary practices for its control.

•    With the planned study, a control and eradication program for paratuberculosis will be implemented in dairy cattle enterprises in Burdur province. The findings obtained within the scope of this study, which will last for five years, can form the basis for control and eradication studies of paratuberculosis in our country.

REGIONAL CONTRIBUTION OF THE PROJECT:
In the literature review conducted within the scope of the project, it was determined that studies aimed at diagnosing paratuberculosis disease in cattle in Turkey are limited. Although the disease has a history of approximately 100 years in Turkey, MAP diagnosis, treatment, and control still remain a problem for researchers.

In a study that also guided this project in Burdur province, ELISA tests were conducted on blood sera collected from 150 cattle. It was concluded that paratuberculosis is prevalent in cattle in Burdur province, with individual, within-herd, and between-herd apparent and true seroprevalence values of 8%, 8.9%, and 17.1%, respectively.

Despite the obtained data, there is still no protection and control program in our country. This leads to an increase in the disease day by day and causes economic losses. Due to the economic losses caused by paratuberculosis and its insidious nature, purchasing animals from enterprises free from pTB for newly formed herds is of great importance. According to TUIK 2016 data, there are 202,499 cattle in Burdur province, making it an important heifer center. Considering all these evaluations, the control of paratuberculosis at the regional level will be ensured. Therefore, awareness will be created with this planned project. The certificate of being free from paratuberculosis will be a preference in determining the animals to be taken into the enterprises. The creation of herds free from paratuberculosis will thus contribute to the regional economy. 

SOCIAL CONTRIBUTION OF THE PROJECT:
Paratuberculosis is a disease with high economic costs, and there is no effective treatment or vaccine for it. The economic losses increase further with the triggering of infertility, mastitis, and other subclinical problems by this disease. Although studies are being conducted in Turkey, the exact prevalence of the disease across the country has not been determined. Therefore, the effects of this disease in our country are not clearly known. Studies show that paratuberculosis is increasing in animals. For this reason, control and eradication programs for paratuberculosis are implemented in some countries. There is no program for the control and eradication of paratuberculosis in our country. It is not a notifiable disease, and there is no vaccine against the disease. The prevalence of infection in sheep and goats is quite high. Studies conducted in Burdur also found that the prevalence of pTB in cattle, sheep, and goats is quite high. pTB is a chronic and insidious disease. Calves acquire the agents when they are less than one month old, and clinical symptoms of the disease can appear after the age of two. During this interval, they intermittently shed the agent through feces. The co-breeding of cattle with sheep and goats or the use of the same pastures is an important route for the transmission of the agent to cattle, as the causative agent of the disease is the same. Especially many subclinically infected animals do not show any clinical signs of paratuberculosis throughout their lives. Only 5-10% of subclinically infected animals in a herd show clinical symptoms. However, these animals play a role in the spread of the agent to other animals and the transmission of the disease. Detecting subclinical animals is important due to their tendency to transmit the disease to healthy ones. Additionally, considering the zoonotic potential of this disease and the resistance of the agent to pasteurization, subclinical paratuberculosis in cattle is also important in terms of public health.

With this project, training will be provided to animal owners and veterinarians about paratuberculosis disease, disease prevention, and eradication studies. Subsequently, fecal and blood serum samples will be collected periodically from dairy cattle enterprises, and the presence of paratuberculosis will be investigated using culture, conventional PCR, and ELISA. It will be recommended to send animals determined to be positive for slaughter. Tests will be repeated every 6 months. Animals determined to be negative for two years will be given a certificate of being free from paratuberculosis. Due to the economic losses caused by paratuberculosis and its insidious nature, purchasing animals from enterprises free from paratuberculosis for newly formed herds is of great importance. According to TUIK 2016 data, there are 202,499 cattle in Burdur province, making it an important heifer center. Considering all these evaluations, the control of paratuberculosis at the regional level will be ensured. Therefore, awareness will be created with this planned project. The certificate of being free from paratuberculosis will be a preference in determining the animals to be taken into the enterprises. The creation of herds free from paratuberculosis will thus contribute to the regional economy.

In line with the results to be obtained from this study, a healthy herd will be created primarily, benefiting animal owners, veterinarians, and official authorities. At the same time, it will form the basis for pTB control and eradication programs to be implemented in our country.