Differences in ingestive behavior between grazing goats and sheep at the bite scale

Area of Science:

• Animal Science
• Behavioral Ecology
• Ruminant Nutrition

Background:

• Understanding ingestive behavior differences between goats and sheep is crucial for pasture management.
• Previous research has focused on diet selection, but bite-scale mechanics remain less explored.

Purpose of the Study:

• To elucidate the specific differences in ingestive behavior between goats and sheep at the bite scale.
• To analyze how sward height and bite depletion influence these behaviors.

Main Methods:

• Grazing trials with goats and sheep on bahiagrass at short and tall sward heights.
• Quantification of ingestive behavior variables: bite rate, bite mass, intake rate, bite dimensions, and bite placement.
• Controlled bite depletion levels (20 and 40 bites).

Main Results:

• Interspecies differences in ingestive behavior were most pronounced in short swards.
• Goats reduced inter-bite distance, increased bite depth, and maintained bite overlap in short swards, leading to greater bite mass.
• Sheep maintained inter-bite distance and reduced bite overlap in short swards, potentially compensating for reduced bite mass.

Conclusions:

• Goats and sheep employ divergent bite-scale strategies, particularly in short swards, influencing their foraging efficiency.
• Goats' adaptations in short swards may help maintain intake rate through efficient chewing and bite mass.
• Sheep's strategies in short swards may partially offset reduced bite mass but not always maintain intake rate.