The aim of this study was to identify proteins in seminal plasma of goats raised in the Northeast of Brazil related with precipitation index and semen quality. Semen was obtained from three bucks and evaluated to the microscopic and macroscopic parameters. The profile of seminal plasma proteins was performed by analysis of two-dimensional electrophoresis. Volume, acrosome integrity and total proteins had significant difference (P<0.05) between the periods of high (1.7mL, 90.3% and 372g mL-1, respectively) and low (1.2mL, 80.3% and 494µg mL-1, respectively) precipitation index. It was detected during high and low precipitation index, 47 and 49 spots of proteins with molecular weight of 4 to 106kDa and 15 to 97kDa, and isoelectric point of 3.00 to 8.96, and 4.48 to 9.83, respectively. Only in the period of high precipitation index were observed groups of proteins with 13kDa and 45kDa. It can be concluded that semen of Alpine American goats raised in the Northeast of Brazil has best quality when obtained in the period of high precipitation index, which can be attributed to the presence of protein with 13kDa and 45kDa.
Capra hircus; rain; seminal characteristics
