A comparative study of various extenders for milkfish, Chanos chanos (Forsskal), sperm preservation

Abstract

Various extenders, containing potassium chloride, sodium chloride, glucose, sodium citrate, Ringer's solution, cow serum and milkfish serum were used to preserve milkfish (Chanos chanos) sperm at near-zero temperatures (0-4°C) and in liquid nitrogen (?196°C). Milkfish serum was a superior extender in both cases. After 5 days, comparatively good motility (> 30%) and fertilizing capacity (6.7-18.9%) were observed in the near-zero liquid samples, while in other extenders, sperm ceased to show motility after 2 days. The fertilization success of 4-5 days cryopreserved sperm averaged 67.5% (n = 2) with milkfish serum, 60.5% (n = 2) with 400 mM glucose, 58.0% (n = 2) with 150 mM sodium chloride, 41.2% (n = 1) with Ringer's solution and 31.9% (n = 2) with cow serum.