Effect of storage time and temperature on stallion sperm DNA and fertility

• Published in: Theriogenology Vol. 57; no. 3; pp. 1135 - 1142
• Main Authors: Love, C.C, Thompson, J.A, Lowry, V.K, Varner, D.D
• Format: Journal Article
• Language: English
• Published: United States Elsevier Inc 01-02-2002
• Subjects: Animals; Chromatin - chemistry; DNA; DNA - analysis; DNA - chemistry; Fertility; Horse Diseases; Horses - physiology; Infertility - veterinary; Male; Nucleic Acid Denaturation; Semen; Semen Preservation - methods; Semen Preservation - veterinary; Sperm chromatin; Spermatozoa; Spermatozoa - chemistry; Spermatozoa - physiology; Stallion; Temperature; Time Factors; Sperm chromatin; Spermatozoa; Semen; DNA; Stallion
• ISSN: 0093-691X; 1879-3231
• DOI: 10.1016/S0093-691X(01)00689-6

We used the sperm chromatin structure assay (SCSA) to study the change in stallion sperm DNA susceptibility to denaturation after exposure of extended semen to three different storage temperatures (5, 20, or 37
°C) at 7, 20, 31, and 46
h. In addition, we compared the rates of sperm DNA denaturation in fertile and subfertile stallions. Among fertile stallions, spermatozoa stored at 20 and 37
°C showed a significant (
P<0.05) rise in the SCSA measures (Mean(
α
t), S.D.(
α
t), and percent cells outside the main population—COMP(
α
t)) over time, with the degree of rise being more dramatic at 37
°C. Over all stallions, samples stored at 5
°C showed no significant (
P>0.05) changes in the SCSA values measured over time, indicating maintenance of chromatin quality for up to 46
h. The COMP(
α
t) from stallions classified as subfertile showed an increased susceptibility to denaturation or decline in chromatin quality between 20 and 31
h when stored at 5
°C; however, spermatozoa from fertile stallions did not change during the time intervals analyzed. These data suggest that sperm DNA from some subfertile stallions may decline at a greater rate than spermatozoa from fertile stallions when exposed to similar storage conditions.