title: Evaluation of parameters related to libido and semen quality in Zebu bulls naturally infected with Trypanosoma vivax.
abstract: BACKGROUND
  Trypanosomiasis is a disease caused by Trypanosoma (Dutonella) vivax, a hemoprotozoa that can affect bovines. In South America, the sanguineous form is mechanically transmitted from one mammalian host (ruminant) to another by the bite of a blood-sucking insect or by needles contaminated with infected blood. The negative impact of the parasitosis caused by T. vivax infection on the reproductive activity of male and female ruminants is known to reduce fertility. In males, alterations such as degeneration, diffuse or interlobular inflammatory infiltrate found in ovine and bovine testicles, can affect fertility through decreased sperm quality. This study evaluated the impact of natural infection with T. vivax on Zebu bulls from the Central Station of Artificial Insemination (CSAI) with regard to libido and the negative effects caused by this protozoan on semen quality.
  
  
  METHODS
  Blood samples of 44 animals were collected to evaluate the presence of the trypomastigote form of T. vivax in blood smears obtained from hematocrit and buffy coat, and antibody titer IgG anti T. vivax in indirect Immunoflorescence (IFI). Furthermore, data related to libido, ejaculate volume, spermatic concentration, and seminal vigor were recorded for these animals employing the criteria of the CSAI.
  
  
  RESULTS
  Nine animals (20.45 %) showed T. vivax trypomastigotes and parasitemia between 0.02 and 0.07, and antibody titers from 1:80 to 1:320 in IFI. Twenty nine negative animals in parasitological tests were not reactive in IFI, and six animals presented the antibodies IgG anti T. vivax in IFI. Data on reproductive activity showed that animals infected with T. vivax have a decreased libido and an increased spermatic volume, whereas other factors related to the reproductive process such as spermatic concentration, motility and spermatic force, were unchanged in infected bulls.
  
  
  CONCLUSIONS
  The T. vivax infection in Zebu bulls from CSAI caused patent parasitemia, induced a febrile state, promoted reduction in the libido and increased the ejaculate volume. These conditions together may account to decrease the performance of these animals.
authors.affiliation: Universidade de Uberaba (UNIUBE), Programa de Mestrado acadêmico em Sanidade e Produçao Animal nos Trópicos, Avenida Nenê Sabino 1697/1698, 38055-500, Uberaba, MG, Brasil. joely.bittar@uniube.br.
authors.forename: Joely F F
authors.initials: JF
authors.lastname: Bittar
authors.affiliation: Universidade de Uberaba (UNIUBE), Programa de Mestrado acadêmico em Sanidade e Produçao Animal nos Trópicos, Avenida Nenê Sabino 1697/1698, 38055-500, Uberaba, MG, Brasil. vet.bassi@gmail.com.
authors.forename: Paula B
authors.initials: PB
authors.lastname: Bassi
authors.affiliation: Universidade de Uberaba (UNIUBE), Programa de Mestrado acadêmico em Sanidade e Produçao Animal nos Trópicos, Avenida Nenê Sabino 1697/1698, 38055-500, Uberaba, MG, Brasil. denia.moura@uniube.br.
authors.forename: Dênia M
authors.initials: DM
authors.lastname: Moura
authors.affiliation: Universidade de Uberaba (UNIUBE), Programa de Mestrado acadêmico em Sanidade e Produçao Animal nos Trópicos, Avenida Nenê Sabino 1697/1698, 38055-500, Uberaba, MG, Brasil. guilhermecgarcia@yahoo.com.br.
authors.forename: Guilherme C
authors.initials: GC
authors.lastname: Garcia
authors.affiliation: Laboratório de Biomarcadores de Diagnóstico e Monitoração, Centro de Pesquisas René Rachou - Fundação Oswaldo Cruz, Avenida Augusto de Lima n° 1715, 30190-002, Barro Preto, Belo Horizonte, MG, Brasil. oamfilho@cpqrr.fiocruz.br.
authors.forename: Olindo Assis
authors.initials: OA
authors.lastname: Martins-Filho
authors.affiliation: Universidade de Uberaba (UNIUBE), Programa de Mestrado acadêmico em Sanidade e Produçao Animal nos Trópicos, Avenida Nenê Sabino 1697/1698, 38055-500, Uberaba, MG, Brasil. andre.vasconcelos@uniube.br.
authors.forename: André B
authors.initials: AB
authors.lastname: Vasconcelos
authors.affiliation: Universidade de Uberaba (UNIUBE), Programa de Mestrado acadêmico em Sanidade e Produçao Animal nos Trópicos, Avenida Nenê Sabino 1697/1698, 38055-500, Uberaba, MG, Brasil. mfernandes@cpqrr.fiocruz.br.|Laboratório de Biomarcadores de Diagnóstico e Monitoração, Centro de Pesquisas René Rachou - Fundação Oswaldo Cruz, Avenida Augusto de Lima n° 1715, 30190-002, Barro Preto, Belo Horizonte, MG, Brasil. mfernandes@cpqrr.fiocruz.br.
authors.forename: Matheus F
authors.initials: MF
authors.lastname: Costa-Silva
authors.affiliation: Universidade de Uberaba (UNIUBE), Programa de Mestrado acadêmico em Sanidade e Produçao Animal nos Trópicos, Avenida Nenê Sabino 1697/1698, 38055-500, Uberaba, MG, Brasil. cristiano.barbosa@uniube.br.
authors.forename: Cristiano P
authors.initials: CP
authors.lastname: Barbosa
authors.affiliation: Universidade de Uberaba (UNIUBE), Programa de Mestrado acadêmico em Sanidade e Produçao Animal nos Trópicos, Avenida Nenê Sabino 1697/1698, 38055-500, Uberaba, MG, Brasil. sobreira@cpqrr.fiocruz.br.|Laboratório de Biomarcadores de Diagnóstico e Monitoração, Centro de Pesquisas René Rachou - Fundação Oswaldo Cruz, Avenida Augusto de Lima n° 1715, 30190-002, Barro Preto, Belo Horizonte, MG, Brasil. sobreira@cpqrr.fiocruz.br.
authors.forename: Márcio S S
authors.initials: MS
authors.lastname: Araújo
authors.affiliation: Universidade de Uberaba (UNIUBE), Programa de Mestrado acadêmico em Sanidade e Produçao Animal nos Trópicos, Avenida Nenê Sabino 1697/1698, 38055-500, Uberaba, MG, Brasil. eustaquio.bittar@uniube.br.
authors.forename: Eustáquio R
authors.initials: ER
authors.lastname: Bittar
mesh_terms: D000818:Animals; D002417:Cattle / Q000469:parasitology; D019084:Fluorescent Antibody Technique, Indirect / Q000662:veterinary; D007989:Libido; D008297:Male; D018512:Parasitemia / Q000662:veterinary; D055101:Semen Analysis / Q000662:veterinary*; D012726:Sexual Behavior, Animal; D016689:Trypanosoma vivax; D014354:Trypanosomiasis, Bovine / Q000469:parasitology / Q000473:pathology* / Q000523:psychology