Tyson Foods Inc. lowered its full-year profit guidance amid trade uncertainties related to tariffs and volatility in commodity markets.

The company now expects an adjusted per-share profit of $5.70 to $6, down from its prior forecast of $6.55 to $6.70. It said Monday that tariffs have hurt domestic and export prices on chicken and pork. Tyson also said domestic chicken demand has weakened because of an abundance of “relatively lower-priced” beef and pork.

“The...