This study is summarised as evidence for the following.

Action Category

Freeze sperm or eggs for future use

Action Link
Amphibian Conservation
  1. Freeze sperm or eggs for future use

    A replicated study of captive cane toads Bufo marinus in Australia (Browne, Clulow & Mahony 2001) found that storage method and temperature affected sperm and egg viability. Sperm stored in testes showed greater than 50% motility for seven days at 0°C and five days at 4°C. By day 15 only sperm stored at 0°C showed any motility (3%). In suspension, the longest retention of motility and fertilizing capacity was following storage in concentrated (1:1 dilution) anaerobic suspensions (up to 25–30 days). However, fertilization rates were significantly higher following storage in 1:5 dilution (day 5: 85% vs 55% for other concentrations). Egg viability was significantly higher following storage at 15°C compared to other temperatures (8 hours: 90% vs 0–60%). Storage at 5°C resulted in a decline to 0% viability after two hours. Sperm from wild toads were stored in intact testes at 0 or 4°C for 15 days (n = 6/treatment) or in suspension (macerated testes; n = 24) with Simplified amphibian Ringer solution at 0°C for 30 days. Dilutions were 1:1, 1:5 or 1:10 (testes:solution) and storage tubes were either opened or sealed. Immediately after ovulation, eggs from three females were stored in simplified amphibian Ringer solution at 5, 10, 15, 20 and 25°C (1,500 eggs/female). Fertilization rate was monitored up until 12 hours.


Output references

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