Table 1.

Advantages and disadvantages of endoscopic versus surgical biopsies of the equine gastrointestinal tract.

Type of biopsy	Invasiveness	Areas where it works well	Layers included	Tissue distortion	Processing artifact	Operator expertise required	No. of biopsies
Endoscopic	Less invasive	Stomach, duodenum, rectum, distal colon	Mucosa; sometimes superficial submucosa	Frequent	Frequent	Significant	Many
Surgical	More invasive	All organs	Full thickness	Infrequent	Infrequent	Routine surgical skills required	Fewer