REPRODUCTIVE INTERVALS AND SEASONAL STRESS: MODULATION OF HSP90 IN HYLA RABBITS

The study was carried out to examine the influence of breeding intervals and seasons on the gene expressing stress proteins, heat shock protein 90 (Hsp90), in Hyla rabbits in southwestern Nigeria. A total of twenty-four healthy adult rabbits, sixteen females and eight males of average 2600g ± 100 g, were used in the study. Does were randomly allotted into the four experimental treatments: T1 (two-week), T2 (four-week), T3 (six-week), and T4 (eight-week) breeding intervals with four rabbits per treatment in a Completely Randomized Design under four different seasons (late rain (S1), early dry (S2), late dry (S3), and early rain (S4)). Blood was collected into EDTA bottles from all does at the middle of each season to quantify the Hsp90 expression. The results showed that Hsp90 mRNAs were expressed in the tested blood from all does in different breeding intervals and seasons. Hsp90 had the higher (p < 0.05) gene expression in S1 and T1. The interaction between breeding intervals and seasons revealed that the expression of Hsp90 was higher (p < 0.05) in S1 across T1-T4. Hsp90 rose as stress increased. Higher levels of cold stress in S1 increased the expression of Hsp90, while stress from gestating and lactating simultaneously increased Hsp90 in T1. The development, production, and reproductive performance of does and their kits would be negatively impacted by the impacts of stress that are greater than the released Hsp90 could control. Therefore, Hyla rabbit keepers should guard against the excess cold during the late rainy season and does gestating and lactating at the same time in southwestern Nigeria.