Stallion spermatozoa prepared by single layer centrifugation with Androcoll™-E are capable of fertilization in vivo.

SLC with Androcoll™-E selects spermatozoa improving quality compared to unselected spermatozoa (Morrell et al, 2009, Theriogenology 72, 879-884). We evaluated Total (TM), Progressive Motility (PM) and fertilizing ability of selected spermatozoa. In Exp 1, ejaculates from one stallion, diluted 1:1 in skimmed milk extender, received one of three treatments: centrifugation at 500 g for 13 min with 3 ml cushion fluid (T1); centrifugation through 15 ml Androcoll™-E at 300 g for 20 min (T2); unselected (US). Pellets were re-suspended, used for motility analysis and artificial insemination (AI). T student test was used for statistical analysis (P<0.05). In Exp 2, an ejaculate from different stallion was used for T2, sperm pellet evaluated for quality and used for AI. In Exp 1,at 24h, TM and PM were higher in T1 and T2 than US (T1 vs US: TM: 30.25±6.65 vs 19.75±4.27; PM: 12.13±4.20 vs 6.25±2.20; T2 vs US: TM: 27.88±8.22 vs 19.75±4.27; PM: 13.9±4.64 vs 6.25±2.20). At 48h storage, TM was better in T1 and T2 than in US (18.67±1.15 vs 10.33±0.6; 20.00±0.00 vs 10.33±0.6); PM, was higher in T2 than T1 and US (10.67±2.51 vs 5.00±1.00 and vs 1.33±0.56). Pregnancy rates were similar (T1:5/11; T2: 3/8). In Exp 2, SLC improved sperm quality (US vs SLC: TM 70% vs. 90%; normal morphology 71% vs. 85.5%; viability 66% vs. 81%); mare became pregnant. In conclusion, SLC improve sperm quality and selected sperm can generate pregnancies after AI.(Funded by the Swedish Foundation for Equine Research)