Principles of Genetics and Breeding

Solution needed

1. Calcium chloride. Treatment with calcium chloride is believed to enhance mitotic division and to counteract the contraction of chromosomes normally produced by colchicine. Inject 0.1% aqueous CaCl₂ solution intraperitoneally.

Length of fish Vol. of CaCl₂

5-10 cm 0.5ml

10-15 cm 0.75ml

15-20 cm 1.0ml

2. Colchicine solution (0.05%) : 0.05g/100ml sterile double distilled water, @ 0.1 ml/10gm of body weight

3. Carnoy's solution - Methanol : Acetic acid (3:1)

4. Hypotonic solution ; KCl : 0.56% (0.075 M) in sterile distilled water or 0.9% aqueous sodium citrate

5. Ethylene glycol – 50 mg/ml. to avoid animal suffering anesthetized.

6. Giemsa stain -Stock solution –

• Dissolve Giemsa powder in 33 ml glycerol and incubate overnight at 60°C in water bath.
  
• Cool it to room temperature.
  
• Add 33 ml of methanol to the above solution.
  
• Filter and use as stock solution.
  
• Store the stain in amber coloured bottle at room temperature.

Working solution

5 ml stock in 95 ml Phosphate buffer is 5% Giemsa solution.

Phosphate buffer stock solution

1. 0.5M KH₂ PO₄ - 6.8g/100 ml d.H₂O

2. 0.5M Na₂ HPO₄ - 17.9g/100 ml d.H₂O

Working solution

1. 0.5M KH₂ PO₄ - 6.26 ml

2. 0.5M Na₂ HPO₄ - 4.56 ml

Dilute up to 500 ml with distilled water.

List of equipment's needed

Cleaned glass slides, Cleaned glass centrifuge tubes (10 ml), Complete set of dissection equipment's all cleaned, Pasteur pipettes with bulbs, Cleaned cavity blocks one each for different samples of fishes, Parafilm strips, tissue paper, Nikon microscope, Tissue homogenizer, Spirit lamp.