Trypanosoma sp. infection in cattle in Argentina. Distribution and characterization of diagnosed cases

ALLASSIA, M; ANGELI, E; VOLKART, S; REINALS, V; AGUIRRE, F; RUIZ M.; PONTARELLI, F; MONJE L; BONTEMPI, I; FLORENTIN, A

Barcelona

Congreso; 31st World Buiatrics Congress; 2022

The National Association of Spanish Specialists in Bovine Medicine (ANEMBE)

Trypanosoma spp. are protozoan hemoparasites that cause different clinical manifestations in various animal spe-cies, including man. The animals can be carriers or devel-op acute to chronic clinical signs. These may be of different severity, even with an important economic-social impact. In America, the main agent is T. vivax, of mechanical transmis-sion by hematophagous vectors such as Stomoxys sp. and Tabanus sp. It is also spread by iatrogenia. In Argentina, T. vi-vax was diagnosed for the first time by Monzón in Formosa in 2006. Since 2016, we have observed several clinical presen-tations in different dairy and beef herds from central Argentina, located in the province of Santa Fe, Córdoba and Santiago del Estero. The most frequent signs were anemia, weight loss, lower production, abortions, edema, diarrhea, sudden deaths. In some cases, there were misdiagnosis, confusing the dis-ease with anemic diseases (anaplasmosis, babesiosis), abor-tigenic diseases (fetopathies such as leptospirosis), digestive processes (mycotoxicosis). The values of packed-cell volume and proteinemia were variable, the liver profile (GGT and GOT) was altered, and the Woo technique positive in some cases. The main lesions correspond to a syndrome of ane-mia and a generalized lymphoadenomegaly. Some cases with hemoperitoneum, without rupture of the spleen or large blood vessels. Microscopically, lymphadenitis and anemia lesions were observed, such as centrilobular necrosis, erythrophago-cytosis. The severity of the cases was diverse, influenced by the productive system (beaf or dairy), level of production (advanced gestation, peripartum, high production), stressful situations (sudden death in caloric stress). The severity of the cases was diverse, influenced by the productive system (beef versus milk), level of production (advanced gestation, peripartum, high production), stressful situations (sudden death in caloric stress). Some cases were closely related to massive vaccinations, and in very few there was a co-infec-tion with Anaplasma marginale. In some of them it was pos-sible to have a PCR molecular analysis corresponding to T. vivax. The treatment established had a positive effect with few recurrences. There were untreated parasitized animals with no signology (asymptomatic). In some of these asymptomatic herds, the reproductive indexes were lower than in previous years. It is essential to identify the hematophagous vectors present, to know their ecology, distribution and behavior, in order to prevent and control the diseases transmitted by them, and to determine how weather conditions may influence the dynamics of infection. The productive conditions of domestic animals must be considered in order to improve their immuno-logical status. In addition, the trade and movement of animals between regions must be known, understood and analyzed. Applying the concepts of spatial epidemiology and medical ge-ography is essential to prevent the consequences of this and other diseases.