Prevalence and Risk Factors Associated With Natural Infection by Trypanosoma evansi in Campeiro Horses.

The study focuses on the prevalence and related risk factors of Trypanosoma evansi infection in Campeiro horses, an endangered breed native to the Santa Catarina plateau region. The research revealed a high prevalence of the infection in the tested population, with certain hematological and biochemical changes identified in the infected horses.

Objective and Methods of the Study

• This study aimed to determine the prevalence of Trypanosoma evansi infection in Campeiro horses, a breed considered to be endangered, and spontaneous to the Santa Catarina plateau region.
• The researchers collected blood samples from 214 Campeiro horses, ranging from 3 months to 27 years of age, from 16 properties in the States of Santa Catarina, Rio Grande do Sul, and Paraná.
• An epidemiological questionnaire was also conducted with the horse owners to identify possible risk factors associated with the infection.
• The collected blood samples were then subjected to various tests including polymerase chain reaction test, immunofluorescence antibody test, complete blood count, and serum biochemistry.

Results of the Research

• The study found a 14% and 59% prevalence of positive Trypanosoma evansi infection, as confirmed by polymerase chain reaction test and immunofluorescence antibody test respectively.
• Changes in blood parameters in infected animals were observed, including increased hematocrit and basophil count, reduced plasmatic fibrinogen and enzymatic activity of alanine aminotransferase, aspartate aminotransferase, and urea, and elevated creatine phosphokinase and creatinine.
• However, these changes in blood parameters are possibly unrelated to the infection as the data acquired from the epidemiological questionnaires displayed no significant difference.

Conclusion of the Study

• The study concluded that Trypanosoma evansi, the causative agent of Surra, a disease affecting horses, is present in the South of Brazil, and is prevalent in the native Campeiro Horse breed.
• The research did not identify any distinct risk factors associated with the disease from the epidemiological questionnaire conducted with the horse owners. Further study may be required to understand the disease’s transmission and persistence within the population.
• The health impacts of the infection deserve further investigation since observed changes in blood parameters might be unrelated to the infection. More comprehensive research involving greater sample size and longitudinal studies may help resolve this.