THE EFFECTS OF PARTURITION AND PERIPARTUM COMPLICATIONS ON THE PERITONEAL-FLUID COMPOSITION OF MARES

Abnormalities in peritoneal fluid are diagnostically useful for managi ng equine colic, however, their significance in post-dystocia mares is not known. This study was to determine what changes, if any, occurred following obstetrical manipulations. Peritoneal fluid samples were co llected from 2 groups of foaling mares to establish control values, an d from a third group that had developed clinical abnormalities (CAb,n= 14) or had made an uneventful recovery (CN, n=36) following fetal extr action. In Group 1 mares, samples were collected before and after indu ced parturitions (n=7), and although the total nucleated cell count wa s increased (P<0.02) the median values for peritoneal fluid compositio n remained within the normal reference range. In Group 2 mares, sample s were collected after unassisted foalings (n=10) on postpartum Days 1 , 3, 5 and 7, and the peritoneal fluid values remained within the norm al reference range. In the Group 3 (CN) mares neither assisted vaginal delivery or fetotomy caused median peritoneal fluid values to rise ab ove the normal reference range. Although remaining within normal limit s, the total nucleated cell count was increased (P<0.01) on Day 2. The median peritoneal fluid total protein value for Group 3 (CAb) mares w as greater than the median value for Group 3 (CN) mares on Day 1 (P<0. 05) and Day 2 (P<0.001). The peritoneal fluid total nucleated cell cou nt in Group 3 (CAb) mares with a uterine tear, vaginal laceration invo lving the peritoneal cavity, or a ruptured mesocolon was greater than in Group 3 (CN) mares (P<0.02). The median peritoneal fluid percentage of neutrophils value for Group 3 (CAb) mares was higher than for Grou p 3 (CN) mares on both Days 1 and 2 (P<0.02). Elevation of a single pe ritoneal fluid value in the postpartum mare may be incidental; however , increases in 2 or more of these (total protein >3.0 g/dl; total nucl eated cell count >15,000 cells/mu l; percentage of neutrophils >80%) i s clinically significant. (C) 1997 by Elsevier Science Inc.