In F1 crosses involving Zebu, what physical marker signals adequate inherited tropical hardiness?

Retention of the large dewlap and moderate hair coat

When commercial producers engage in cross-breeding Zebu cattle with European stock specifically for beef production in hot regions, they closely monitor the physical characteristics passed down to the offspring. Key physical markers used to assess the successful inheritance of tropical adaptation are the persistence of the large dewlap and the maintenance of a moderate hair coat. If producers observe a rapid reduction in the size of the dewlap in these F1 crosses, it serves as an important signal that the animals might require more intensive management strategies to counter potential heat stress, as the large dewlap is a highly reliable visual indicator of superior, inherited resistance to heat.