While it is true that cows do exhale oxygen but that is applicable on all living beings. ... All animals (and even humans) exhale some amount of oxygen that they breathe.

How do cows breathe?

Experts have clarified in the past that cows, like any other animal, exhale carbon di-oxide, other gases, and some of the residual oxygen it inhales. In fact, cows emit methane while belching.

Do animals breathe out oxygen?

All animals respire. ... Well, respiration usually requires oxygen, and animals get their oxygen by breathing.