The seminal plasma originates mainly from the epididymis and accessory sex glands. Epididymal proteins provide conditions for sperm maturation and storage while accessory sex gland components mediate events such as sperm capacitation and motility, acrosome reaction, protection against oxidative stress and immune responses, sperm contact with oviductal epithelium and fertilization. In this regard, we emphasize that identification of proteins from the male fluids is essential to understand sperm function. In most of Brazil, sheep has no wool, being therefore unique genotypes because of their exceptional adaptability to the tropics. Given the importance of these animals, we have taken the effort to study aspects of their physiology, including testis development and gamete function. As part of that broad objective, the present work had the focal point on the proteomics of seminal plasma. Semen was collected from 10 yearling animals and centrifuged to obtain the seminal plasma. Samples with 350 μg of protein were electrophocused (13 cm IPG strips; pH 4 to 7), followed by SDS-PAGE (15 %) and analysis of Coommasie-stained gels using PDQuest software (Bio Rad, USA). We identified 322 ± 21 spots per gel, from 12 to 160 kDa. Spot clusters #110 (14 kDa; pI 5.2) and #4004 (14 kDa; pI 5.8) represented, respectively, 15.1 and 6.3 % of the intensity of all protein spots of the 2-D maps. These clusters were excised from gels (as two separate spots each), digested with trypsin and processed for mass spectrometry (Maldi-Tof-Tof), followed by data search (Mascot and NCBInr). Two spots from cluster #110 showed homology with isoform 2 of bodhesin (gi 121484235), a spermadhesin originally described in goats. A third spot (15 kDa; pI 6.5), covering 1.3% of all spot intensities, was identified as isoform 1 of the same protein (gi 77864607). Spermadhesins are present in seminal plasma from bulls, European rams, stallions and swine, and may influence sperm capacitation, motility, acrosome stabilization and sperm-oocyte fusion. Our previous studies described an inverse association between seminal plasma spermadhesin Z13 and dairy bull fertility and indicated that this protein is a constituent of the sperm membrane protein extract. The two spots of cluster #4004 had significant identity to "ram seminal vesicle 14-kDa protein - RSVP-14" (gi 1346343) and reacted with antibodies against the bovine BSP1 (former BSP A1/A2), as evaluated by Western blots. We also found that ejaculated sperm from the hairy rams reacted with those antibodies, showing fluorescence on the acrosome, equatorial segment and midpiece. The RSVP-14 has been previously found in seminal plasma of Spanish Rasa aragonesa rams and may protect sperm from effects of cold shock. Interestingly, our prior results indicated that both bodhesin and RSVP-14 were one of the first proteins appearing in seminal plasma maps from hairy rams as early as 15 weeks of age, well before the first motile sperm cells were present in semen (23.1 weeks). Other major spots in the maps of ram seminal plasma included a cluster of 8 spots at 25 kDa (pI from 4.2 to 4.7) and at 90 kDa (pI from 4.2 to 4.7), equivalent to 16.6 and 10.3 % of all spots intensities. Many other spots appeared as "trains", suggesting they are different isoforms of the same protein, as we have seen before in gels of reproductive fluids from other species. Study funded by grants (to AAM) from the Brazilian Research Councils (CNPq and CAPES).(poster)