When food enters the small intestine, bile travels through the common bile duct to reach the duodenum. Gallstones are hard deposits that form inside the gallbladder when there is too much bilirubin or cholesterol in the bile.
That said, there is a considerable consensus that all three major trout species (brook, brown and rainbow) begin to experience some level of stress at around 68Â°F (20Â°C), with that stress increasing rapidly as the temperature rises further.
Rainbow trout spawn earlier in their lives than most other trout species (at roughly two years) and their spawning season occurs in the late spring and early summer as water temperatures rise. Brown trout spawn in the fall, from late September to early November, and are primarily active during the daytime.