ANN 121: Applied Animal Nutrition-I (2+1)

PHYSICAL TREATMENT

Soaking

• Chopped straw is soaked in water overnight.
• Softens the straw leading to increased intake.
• Disadvantage is mould growth.

Chaffing

• Decreasing particle size.
• Increases surface area for action of rumen microbes and hence increase digestibility.

Grinding

• Particle size reduced still further. (0.1 to 0.3 cm).
• Disadvantage is that it increases rumen flow rate, decreases retention time in the rumen leading to decreased production of acetate causing a condition of low milk fat syndrome.

Steam pressure

• Straw treated with Steam at pressure of 21.1 kg/cm² for 10 to 30 seconds.
• Causes rupture of lignocelluosic bonds to a certain extent and makes cellulose available for microbial action.

Explosion

• Chopped or ground straw is treated with steam at pressure of 22.5 kg/cm² for two minutes and pressure is suddenly released.
• Causes rupture of lignocelluosic bonds to a certain extent and makes cellulose available for microbial action.

Irradiation

• Straw is treated with γ irradiation. Causes rupture of ligno celluosic bonds and makes cellulose available for microbial action.

Pelleting

• Particle size reduced to 0.1 to 0.3 cm and pelleted through 1-2 cm die.
• Retention time in the rumen increases .