Prevalence and risk factors associated with Tritrichomonas foetus infection in cattle in the state of Paraíba, Brazil
The objective of this study was to determine the prevalence of Tritrichomonas foetus infection and to evaluate risk factors associated with this infection among cattle in the state of Paraiba in northeastern Brazil. Samples of cervicovaginal mucus from 290 females and smegma from 59 males [beef, 31; mixed aptitude (beef and dairy), 10; and dairy, 18] from 31 farms were collected. Modified Diamond’s medium and polymerase chain reaction (PCR) were used for the laboratory diagnosis of T. foetus infection. Univariate analysis and logistic regression were performed to test for potential risk factors in addition to prevalence mapping. No sample was positive for T. foetus in culture, and the prevalence of T. foetus infection using PCR was 3.7% (13/349) [confidence interval (CI) 95%, 2.1%–6.4%]. In total, 19.3% (6/31) of the farms had at least one animal positive for T. foetus. The contact of females with males from other farms [Odds ratio, 5.9; 95% CI, 1.5–22.4; p = 0.009] was identified as a risk factor for T. foetus infection. This study demonstrates that T. foetus infection is prevalent among dairy cows in the state of Paraiba, Brazil. Sexual resting, removal of positive females, and avoiding contact of females with males from other farms are recommended to reduce the risk of infection.
Detección de Tritrichomonas foetus por PCR en esmegma prepucial de toros en Uruguay
Bovine trichomoniasis is a venereal disease caused by Tritrichomonas foetus. It is responsible for economic losses worldwide, causing mainly infertility and abortion in cows and heifers. The diagnosis of this disease is mainly based on microbiological culture and on molecular testing. In Uruguay the parasite has not been reported since 2005. The aim of this study is to report the detection of T. foetus by PCR in preputial smegma from bulls from dairy and beef Uruguayan farms. A total of 310 smegma samples, 121 from dairy-production-bulls and 189 from meat-production-bulls, were sampled. Animals came from 56 farms distributed within 12 different departments of Uruguay. While the PCR analysis of preputial smegma identified 2.25% (7/310) positive for T. foetus, no culture-positive samples were detected. The parasite was detected in 5% (6/121) of the sampled bulls for dairy production, these six animals were from the same dairy farm.  Tritrichomonas foetus was only detected in one out of 189 animals from beef production. This study showed that 3.4% (1/29) and 3.1% (1/32) of beef and dairy farms respectively, were positive for T. foetus infection. PCR is advantageous over culture; therefore, it is an efficient and quick method for the detection of T. foetus in preputial samples. The results of this work suggest that the parasite detection may be underestimated due to the use of only culture-based diagnostics.
Comparison of the Diagnostic Sensitivity of a Commercially Available Culture Kit and a Diagnostic Culture Test Using Diamond's Media for Diagnosing Tritrichomonas Foetus in Bulls
A number of different culture media have been described for use in the diagnosis of Tritrichomonas foetus infection in bulls, and recently, a commercial culture kit has become available. The objective of this study was to compare the sensitivity of 2 culture-based diagnostic tests for T. foetus in bulls. One test used a commercial kit for transport and culture of the samples. The other test used a thioglycollate transport medium (TFTM) for transport and a modified Diamond's medium (MDM) for culture of the samples. Twenty-one bulls infected with T. foetus were sampled repeatedly. On each sampling day, samples collected from the left and right sides of the bull were tested with one of the 2 diagnostic tests being compared. The effect of the type of diagnostic test on the outcome of the test was evaluated with a chi-square test for the calculated odds ratio. Because repeated tests from the same bull cannot be considered independent measures, unadjusted chi-square tests were adjusted for the effect of clustering by bull. Samples tested using the commercial kit were 6.95 times as likely to be positive as samples tested with a diagnostic test using MDM (P < 0.001).