Species with Salivary Amylase

Salivary amylase is present in the saliva of-

Correct Answer: Pig

Salivary amylase (ptyalin) is present in the saliva of Pig (and also in Humans). It initiates starch digestion in the mouth (oral cavity).

Why Not in Ruminants, Horse, or Cat?

• Ruminants: Saliva contains NO amylase. Instead, it is rich in NaHCO₃ and Na₂HPO₄ buffers (pH ~8.0) to neutralize ruminal VFAs. Adult cow secretes ~150 litres of alkaline buffering saliva per day. Carbohydrates are fermented by ruminal microbes → VFAs (not glucose).
• Horse: Little or no salivary amylase. Horses are hindgut fermenters; starch digestion occurs enzymatically in the small intestine.
• Cat: No salivary amylase AND no taste receptors for sweetness. Cats are strict obligate carnivores with minimal carbohydrate metabolism.

Carbohydrate Digestion Comparison

• Ruminants: No salivary amylase → microbial fermentation in rumen → end product = VFAs
• Non-ruminants (pig, human): Salivary amylase → starch digestion starts in mouth → end product = glucose → absorbed by active transport in small intestine