Jefferies analyst Akshay Jagdale attributes yesterday's pullback in shares of Tyson Foods to concerns about the newly disclosed SEC investigation and ongoing worries about peaking margins. The SEC investigation represents a short-term overhang but Beef and Pork margins will eventually normalize, Jagdale tells investors in a post-earnings research note. The analyst believes the chicken price-fixing allegations are unfounded. He keeps a Buy rating on Tyson's with a $75 price target. The company's "value-added earnings stream remains significantly undervalued," Jagdale writes.