Only with a guinea pig-- poor thing got constipated!!!
Realize, the celery 'strings' are the support framework for a VERY heavy plant! Kind of like 'stays' in old fashioned corsets, or that darn uncomfortable wire in a support bra-- The strings of celery contain much higher levels of cellulose, what one could call 'wood' IN the wild, grazers generally do not eat plants that contain high levels of silica (wetland plants like Spike rush, nut sedge, horsetail), nor do they eat 'Old' twigs or branches -- yes, they will debark, eat the soft cambium layers, but not the mature xylem and phloem of a plants support structure.