Abdominocentesis techniques in horses.

Abdominocentesis is useful as a diagnostic procedure in horses suffering from colic, diarrhea, weight loss, or other conditions involving the abdominal cavity and is an integral component of diagnostic testing for colic at referral institutions or in the field. Abdominal fluid collection using an 18-Ga, 3.8-cm (1.5-in) needle is recommended for adult horses because the needle is long enough to penetrate the peritoneal cavity. The teat cannula technique is recommended for use in adult horses, foals, and miniature horses to reduce the risk of enterocentesis, even though this procedure is more traumatic than using an 18-Ga, 3.8-cm needle. Ultrasonography of the abdomen is a valuable tool in the assessment of any horse with signs of colic, but it is not essential for performing an abdominocentesis successfully.