Fatigue characteristics and biocompatability of a totally implantable bone growth stimulator in ponies

Materials fatigue and gross biocompatability of an implantable bone growth stimulator (BGS) were assessed in a 6-month trial using 6 ponies. The forelegs of each pony were implanted with a BGS; the right leg implant had the cathode and cathode lead preconnected by the manufacturer, and the left leg implant was connected at surgery. Evaluation was by radiographic and clinical examination at the beginning and end of the experimental period. Six of the 12 cathode leads (50%) and 7 of the 12 cathodes (58%) were broken at 6 months. All of the implanted preconnected cathode and insulated cathode leads and 33.3% of the surgically connected cathodes and insulated cathode leads were connected at the titanium connector socket at 6 months. This BGS may exhibit wire fatigue greater than 50% of the time when used in the distal extremity of the horse.     

Equine colonic motility: interactions among wall motion, propulsion, and fluid flow

Transmission of intestinal content with respect to wall position and intraluminal pressure was studied using implanted catheters in portions of the haustrated left ventral colon and nonhaustrated pelvic flexure and left dorsal colon in 3 conscious, standing, and feeding ponies. Wall position and content movement was studied in 1 noncatheterized conscious pony that was standing and eating. When coordinated wall movements involving greater than or equal to 30 cm of adjacent colon were seen, point-to-point content movement accompanied intraluminal pressure peaks occurring in the same direction. Near the pelvic flexure, intraluminal pressure peak maximums coincided and reduced colonic diameters and reduced intercatheter distances. Qualitative observation of 3 related aspects of intestinal motility: wall motion, propulsion, and fluid movement can be studied in the conscious feeding pony.     

Portosystemic shunts in cats: seven cases (1976-1984)

Congenital portosystemic venous shunt causing signs of hepatic encephalopathy was diagnosed in 7 cats. The left gastric vein served as the shunt in four of these. Increases in blood ammonia and postprandial serum bile acids were the most consistent serum biochemical abnormalities. Excessive variation in red blood cell shape was a common but nonspecific hematologic finding. The jejunal-mesenteric venous injection of contrast material was the preferred method of portography to diagnose portosystemic shunts. Two cats were treated successfully by partial surgical occlusion of their shunts.