Gestation period of some animals

• Elephant : 21-22 months
• Yak: 9 months
• Rabbit: 30-35 days ( 1 month)
• Rat: 21-30 days ( 1 month)
• Rhinoceros: 530-550 days ( 1 year and 2 months)

Semen volume of some species

• Man: 3.5 ml
• Bull : 8 ml
• Buffalo: 2.5 ml
• Ram: 1 ml same as buck
• Stallion: 12.5 ml
• Jack: 50 ml
• Dog: 10 ml
• Rabbit: 0.5 ml

Storage of frozen semen

• -79⁰C : using solid CO₂ ( dry ice) and alcohol.
• -190 ⁰C : used liquid air
• -196⁰C : using liquid nitrogen
• -296⁰C : Using liquid helium.