Immunocontraception of captive exotic species. II. Formosan sika deer (CERVUS nippon taiouanus), axis deer (Cervus axis), himalayan tahr (Hemitragus jemlahicus), roosevelt elk (Cervus elaphus roosevelti), reeves' muntjac (Muntiacus reevesi), and sambar deer (Cervus unicolor)

A porcine zonae pellucidae (PZP) vaccine was tested in 45 animals of six species of captive exotic ungulates, including Formosan sika deer (Cervus nippon taiouanus), axis deer (Cervus axis), sambar deer (Cervus unicolor), Roosevelt elk (Cervus elaphus roosevelti), Reeves' muntjac (Muntiacus reevesi), and Himalayan tahr (Hemitragus jemlahicus). All animals except muntjac and tahr were inoculated with an initial series of two or three i.m. injections of 65 μg PZP with either muramyl dipeptide or Freund's incomplete adjuvant over a 6-wk period, followed by annual booster inoculations. Muntjac received doses of 43 μg PZP and Himalayan tahr received doses of 48-65 μg PZP. There were significant differences in pre- and posttreatment fertility rates, and contraception was effective in Formosan sika deer, Himalayan tahr, and Roosevelt elk, moderately effective in axis deer, not effective in sambar deer, and of inconclusive effectiveness in Reeves' muntjac. Immunization with PZP produced progressively elevated anti-PZP antibody titers in most animals. Two Formosan sika deer fawns, two axis deer fawns, one Roosevelt elk calf, and two sambar deer fawns whose mothers became pregnant after inoculation with PZP were born healthy. Animals pregnant when inoculations began included one Formosan sika, one axis deer, and three sambar deer. The sika deer delivered a healthy fawn, the axis deer delivered a stillborn fawn, one of the three sambar fawns was stillborn, and a second sambar fawn was abnormal. Six of 13 sambar deer fawns that were conceived after inoculation and were exposed to the PZP vaccine, adjuvants, and anti-PZP antibodies during gestation were born with a variety of weaknesses and health problems or were stillborn. Reversibility of contraceptive action after 1 yr of treatment with PZP was demonstrated among muntjac but has not been fully evaluated in the other species. Inoculation of pregnant sambar deer with PZP and either muramyl dipeptide or Freund's incomplete adjuvant may lead to congenital abnormalities or stillbirths.