Annual Changes in Spermatozoan Production and Associated Organs of White-Tailed Deer

Abstract

The left testis and epididymis were collected from each of 60 wild adult (> 12 mo. old) male white-tailed deer (Odocoileus virginianus) over approximately 1 yr in southwest Virginia [USA]. Testes and epididymides were weighted separately and numbers of spermatozoa in each organ were determined. All gonadal parameters were at baseline values from Feb.-June. Testis and epididymis weights and testicular spermatozoan numbers rose markedly from June to July. Epididymal spermatozoan numbers increased from July to Aug. as storage of spermatozoa began. Testis and epididymis weights (g) and testicular and epididymal spermatozoan numbers (.times. 109) increased to maximum values (46.76 .+-. 8.16 SE, 7.40 .+-. 1.11 SE, 4.406 .+-. 0.577 SE and 6.602 .+-. 1.600 SE, respectively) during Nov. when does normally are bred in southwest Virginia. Male deer apparently have breeding capability and sexual libido from the latter part of Sept.-Jan. in the study area. The breeding capability of the male had begun to diminish in Dec. as indicated by the regression of all gonadal measurements.