Many calves are dehorned between six and 10 weeks of age. But that may be too late, according to one expert. 

Sam Leadley, calf-care expert who works in conjunction with Attica (N.Y.) Veterinary Associates, says 21 to 28 days is a good time to dehorn calves when using the gouging or cauterizing methods. 

By the end of the third week, calves that have been properly fed may have developed enough immunity to deal with the stress of dehorning (from gouging or cauterizing methods), Leadley says. Yet, they are still young enough that the amount of tissue damage is minimized.

Caustic paste is another story. “All of the producers that I have contact with (who use caustic paste) do this as early as possible,” Leadley says. Some do it as part of the intake procedure at one to two days of age.