• In Sacco Nylon Bag Degradation Dynamics:
• Ørskov and McDonald (1979) established the non-linear exponential model to describe ruminal nutrient disappearance over incubation time ($t$):

where:

• $p$ = degradation at time $t$
• $a$ = rapidly soluble, instantly washable fraction (intercept)
• $b$ = potentially degradable insoluble fraction
• $c$ = fractional rate constant of degradation of fraction $b$
• The effective degradability ($P$ or $ED$) accounting for rumen outflow rate ($k$) is:

• nalysis:
• Correct mathematical representation of the potential degradability equation ($p = a + b(1 - e^{-ct})$).

Correct option: (3) P=asb (1-2)

• CNCPS Protein Partitioning:
• Fraction A: Non-Protein Nitrogen (NPN), instantly degraded in the rumen ($A = \text{Soluble Protein} - \text{True Soluble Protein}$).
• Fraction B1: Rapidly degraded true protein (buffer soluble, TCA precipitable).
• Fraction B2: Moderately degraded protein ($B2 = \text{Total Protein} - A - B1 - B3 - C$).
• Fraction B3: Slowly degraded protein associated with plant cell walls:

(Neutral Detergent Insoluble Protein minus Acid Detergent Insoluble Protein).

• Fraction C: Completely indigestible protein ($C = \text{ADIP}$).
• nalysis:
• (NDIP - ADIP): Correct definition of Fraction B3.

Correct option: (4) NDIP -ADIP