Parasitic tristeza is a disease transmitted by ticks and is one of the main causes of death in cattle in our country. Economic losses are not only caused by the death of animals, but also by a decrease in meat and milk production, abortions and added costs for treatment and labor. How does the disease occur and how is it transmitted? Parasitic tristeza is caused by three agents: Babesia bovis, Bavesia bigemina and Anapala mamarginale. These are microscopic parasites found inside red blood cells (hemoparasites). Babesia bovis and bigemina are transmitted only by the common cattle tick. Anapala mamarginale, in addition to being transmitted by ticks, can also be transmitted by horseflies, by the use of instruments such as castration and dehorning knives and also by the collective use of needles without proper disinfection, which can carry blood from one animal to another. Outbreaks of these diseases are related to the number of ticks present, which is why in autumn, when there are more ticks on cattle, the greatest number of cases of parasitic tristeza occur. In the case of Anasplasmosis, outbreaks can occur at the beginning of winter due to its longer prepatent period. The mere presence of a tick does not determine the occurrence of the disease, because it may or may not be infected by Babesia or Anaplasma. What are the clinical signs? In all three diseases, the following are observed: fever of 40-41°C, depression, isolation from the herd and anemia (pale mucous membranes). In babesiosis, blood-colored urine can be observed, which does not occur in anaplasmosis. In babesiosis caused by Babesias bovis, nervous clinical signs are observed. Deaths caused by these three agents are related to the age of the animals. These diseases have a high mortality rate in cattle older than 2 years, moderate in over-yearling animals and mild in calves. When we have sick animals we must be very careful in their handling as sudden deaths can occur when they are moved. Diagnosis. For the diagnosis we must resort to the anamnestic and epidemiological data of the establishment, this together with the clinical signs will guide us in the diagnosis. In the case that they predispose deaths and a necropsy is performed we will find characteristic lesions such as; jaundice (generalized yellowish color), enlargement of the liver and spleen. In the bladder we can find hemoglobinuria (dark colored urine). Finally, blood with anticoagulant is sent to the laboratory, preferably peripheral (tail) for confirmatory diagnosis. How is it prevented? First of all, it is necessary to make a diagnosis of the enzootic balance/imbalance situation. For this purpose, a blood sample with anticoagulant is taken from a percentage of the total number of animals and a DILAVE is sent for serological study. If 80% or more of the herd is diagnosed as positive, it is considered as enzootic balance. In this case there is no greater risk of deaths due to tristeza. The same occurs when less than 20% of the herd is serologically negative. When the positive diagnosis is between 20 and 79% of the herd we are facing a situation of enzootic imbalance. In this case it is very likely that deaths due to tristeza may occur. For the prevention of parasitic tristeza there are two vaccines, one refrigerated and one frozen. Both are safe to use in calves under nine months old. For immunity to be effective it is advisable that they are applied by veterinarians who will take into account the situation of each establishment and the general state of the herd. As Anapalsma is transmitted by the collective use of contaminated needles and instruments, one of the prevention measures is to disinfect the materials between animals. Treatment Imidocarb (Stand Up) is the drug of choice for both curative and prophylactic treatment of parasitic tristeza. Keys to improve livestock production. Keys to improve meat production keys to improve milk production. What is dual-purpose cattle? How many liters of milk does a dairy cow give? How can leptospirosis be prevented? What is the causal agent of leptospirosis? How does leptospira affect cattle? What is leptospirosis? What is leptospirosis in cattle? What is the treatment for leptospirosis? How is leptospirosis spread? How is bovine tuberculosis spread? How is brucellosis transmitted in cattle? What is leptospirosis in cattle? What is leptospirosis in cattle?