EN 
PT_BR 
The rainy season, which typically extends from the end of spring to the beginning of autumn, represents a period of high humidity and elevated temperatures in the main livestock-raising regions of Brazil. These conditions, while beneficial for pasture growth, favor the multiplication of gastrointestinal parasites and disease vectors, making it essential to intensify vaccination and deworming efforts for livestock.
According to Rodrigo Costa, who works in the field in the states of Mato Grosso and Mato Grosso do Sul, this combination of factors can generate significant losses. “Humidity favors the survival of worm eggs and larvae in the pasture, in addition to creating ideal conditions for the spread of infectious agents, such as bacteria and viruses. These factors increase the risk of contamination and compromise the productive performance of the animals. If there is no good sanitary control, the producer may face a drop in milk and meat production and an increase in costs with corrective treatments,” he warns.
Among the diseases with the highest incidence at this time of year are clostridial diseases, such as symptomatic anthrax (blackleg) and enterotoxemias, which tend to worsen with the ingestion of very rich pastures, favorable to the development of clostridial bacteria and the production of toxins.
Also deserving of attention are leptospirosis, which spreads in humid areas through rodent urine and affects herd reproduction, and hemoparasitic diseases, such as anaplasmosis (bovine parasitic tristeza) and babesiosis, transmitted by ticks. In addition, there is the risk of gastrointestinal worm infestations (mainly Haemonchus contortus and Trichostrongylus spp.), which cause anemia, diarrhea, and weight loss, and an increase in flies such as horn flies.
According to Costa, the vaccination schedule is one of the main tools for preserving herd health and avoiding economic losses. “Keeping the vaccination protocol up to date is essential to prevent disease outbreaks that can compromise farm profitability. In regions where vaccination is mandatory, such as in the case of foot-and-mouth disease, non-compliance can lead to legal penalties and trade restrictions,” he mentions.
The professional further emphasizes that parasite control should be carried out according to the herd's profile and the farm's history. Calves and young animals, for example, are more vulnerable and should be dewormed every 60 to 90 days. Adults can have longer intervals, provided the infestation level is under control. “Ideally, fecal exams (EPG – eggs per gram) should be performed to identify the degree of contamination and determine the most appropriate dewormer. It is also important to alternate active ingredients, preventing the development of parasite resistance to medications,” he advises.
Warning signs of possible infestations include chronic diarrhea, weight loss, pale mucous membranes, and ruffled fur. In cases of immunization failures, diseases may appear in already vaccinated animals, a situation that may indicate the use of poorly preserved, expired, or incorrectly administered vaccines. "Upon identifying any abnormality, the producer should seek the support of a veterinarian or technician to confirm the diagnosis through clinical and laboratory examination, in addition to reviewing vaccination and deworming protocols," emphasizes Costa.
The correct choice and application of products are also crucial for the effectiveness of treatments. It is essential to opt for vaccines and dewormers registered with the Ministry of Agriculture, observe proper storage (generally between 2 and 8°C), and ensure that application is done with clean and calibrated equipment. “These simple precautions make all the difference. Poorly performed applications or poorly stored products can compromise the herd's immunity and generate waste,” he emphasizes.
Costa also highlights the role of technical assistance in the sanitary planning of properties. “The support of qualified professionals helps producers to create an efficient vaccination and parasite control schedule, according to the reality of each farm. Furthermore, specialized monitoring allows for continuous evaluation of results, adjustment of strategies, and assistance in selecting the most cost-effective products to guarantee the health and productivity of the herd,” he emphasizes.
