The effects of experimental Trypanosoma congolense infection on the ejaculate of rabbits and changes caused after treatment with Diminaveto® were investigated using 24 New Zealand White rabbits (bucks). The bucks were housed singly in standard rabbit cages and fed on specialized ration containing 10% Protein supplement, grains, legume, salt and fresh water ad libitum during the study. Data on ejaculate characteristics were collected from all the bucks in the first phase (i.e. before infection) and in the second phase (i.e. during infection, with 4.8x10(5) Trypanosoma congolense, intraperitoneally). Similar data were collected from 12 randomly selected bucks treated with 7.0mg/kg Diminaveto® following reconstitution during the third phase. Data collected were analysed using the Paired T- Test and Analysis of Variance. The infection led to significant (P< 0.05) reduction in spermatozoa motility, concentration and mass activity, with a significant (P< 0.05) increase in percentage of sperm cells with morphological abnormalities. Treatment with Diminaveto® led to improvement in all ejaculate parameters investigated. However, it was observed that the ejaculate did not attain the "before-infection" status following treatment with Diminaveto®. The study showed that infection with Trypanosoma congolense in rabbits caused significant reduction in ejaculate characteristics. Treatment with Diminaveto® however led to improvement in the ejaculate though at a rate slower than that at which the infection caused the reduction.