Comparative digestion of timothy (Phleum pratense) fibre by ruminants, equines and rabbits.

This research compares the ability of cattle, sheep, goats, horses, and rabbits to digest mature timothy hay. The study found that ruminants were better at digesting the hay’s fibre components than horses, which were in turn better than rabbits.

Objective and Study Design

• The primary aim of this study was to compare the digestion abilities of different animals – cattle, sheep, goats, horses, and rabbits – when fed mature Timothy hay. The researchers also sought to understand the impact of the animals’ body weight on digestion efficiency.
• Specifically, the researchers measured and compared the apparent digestibility, true digestibility, metabolic faecal output (MFO), and fibre digestibility in these animals.

Results and Findings

• The study found that ruminants (cattle, sheep, goats) were better at digesting the fibre components of the hay than the equines (horses), which were in turn superior to rabbits.
• Among equines, there was a high variation in digestibility between individuals.
• An increased body weight correlated with higher digestibility in ruminants, but no such trend was observed in non-ruminants (horses and rabbits).
• The metabolic faecal output (MFO), measured as a proportion of dry matter intake, gave similar values across all animal groups studied. This suggests that the type of animal does not significantly affect the metabolic waste produced during the digestion of Timothy hay.
• A surprising finding was that, as a proportion of available microbial substrate originating from the feed, the values were highest for rabbits. This suggests that their intestinal microflora obtain energy primarily from non-fibre components of the feed, unlike the ruminants and horses.
• For horses, the data did not show substantial digestion of the generated microbes by the host, implying that microbial metabolism does not significantly contribute to their overall energy.