Doesn PZP effect deer behavior in a negative manner?
Since they do not become pregnant, treated deer cycle for a longer period than usual. Female deer can have from 2 to 4 additional estrous cycles each year. Scientific data, however, shows that the following spring treated deer not producing fawns weight more and are thus in better condition than untreated females, perhaps due to the “biological costs” associated with 9-10 months of pregnancy and nursing. Evidence suggests that by the second or third estrous cycle dominant males yield breeding privileges to younger males so that energy expenditures are shared and no single animal becomes exhausted. Other species, such as horses, do not experience additional estrous cycles. Horses vaccinated with PZP live longer than ordinary and show extraordinary good health into old age.
