I've been doing Plantar Incision surgeries in rat but can't seem to get consistent guarding behavior 24 hours post-surgery. What am I doing wrong?

I am making an incision about 1cm from the back of the heel to the middle of the foot and excising the muscle and making an incision in the muscle. I am then suturing the skin back after hemostasis. But 24 hours post surgery, the guarding behavior that I am seeing is very variable. I can't understand what I'm doing wrong to get this consistent inconsistency.