A study of spermatozoan reserves of male white-tailed deer and of the reproductive physiology of fawns

Abstract

Reproductive organs from 73 male white-tailed deer (Odocoileus virginianus) were collected in November and in December in South Carolina. Organ weights and spermatozoan reserves were analyzed by age class and for variation between months. Testes weights (g) in November were 15.12 ± 8.03, 61.53 ± 17.16, and 75.69 ± 13.71 for 0.5, 1.5, and older deer, and 14.81 ± 5.34, 46.66 ± 8.91, and 61.62 ± 12.91 in December, respectively. Epididymides weights (g) were 3.31 ± 0.78, 9.61±1.99, and 12.53 ± 2.30 in November and 3.36 ± 1.02, 8.92 ± 1.31, and 10.50 ± 2.07 in December for 0.5, 1.5, and older deer, respectively. Spermatozoan numbers (xl0⁹) in the testes were 0.182 ± 2.23, 6.59 ±. 2.96, and 8.46 ± 3.10 for 0.5, 1.5, and older deer in November and 0.108 ± 0.213, 5.05 ± 1.05, and 4.86 ± 2.23, respectively, in December. Epididymal spermatozoan numbers (xl0⁹) in November were 0.087 ± .174, 9.43 ± 2.85, .and 11.89 ± 4.15 in 0.5, 1.5, and older deer, respectively, and 0.094 ± 0.173, 8.73 ± 2.44, and 9.01±4.18, respectively, in December. The 1.5 year old deer had significant (P<0.05) lighter testes weights than 2.5 years old and older deer in November and December. There was a significant (P<0.05) reduction in testes weights and testicular spermatozoan numbers between November and December in adult deer. Fawn testes and epididymides weights, and testes and epididymides spermatozoan reserves were significantly (P<0.05) lower than older deer in November and in December. Nineteen male and 21 female fawns collected from the Radford Army Ammunition Plant were examined to ascertain attainment of puberty. One female was pregnant and three males had evidence of spermatogenesis.