M. Nicodemus

Temporal variables of four-beat, stepping gaits of gaited horses

Abstract Gaited horse breeds perform a variety of four-beat stepping gaits that are recognized and distinguished by the sequence and timing of the footfalls and by the limb support sequences during the stride. The popularity of the gaited horse breeds is increasing and accurate descriptions of limb kinematics are needed both to define the performance characteristics of the different gaits and to assist in identifying gait pathologies. The objective of this study was to measure the temporal stride variables of 16 four-beat stepping gaits using frame-by-frame analysis. The gait sequences used for analysis were selected by the breed associations as being representative of correct performance of each gait. The results showed that all gaits were classified as symmetrical. A regular four-beat rhythm was present in the classic fino, coon rack, marcha picada, mountain pleasure rack, paso llano, rocky mountain rack, style rack, road gait, and toelt. An irregular rhythm with diagonal couplets characterized the fox trot, marcha batida, paso corto, and paso largo, while lateral couplets were found in the running walk, curly rack, and sobreandando. Three distinct limb support sequences were identified, with only the marcha batida demonstrating a period of quadrupedal support. Hind limb stance was longer than forelimb stance in the paso corto, paso largo, style rack, and running walk.

Effects of feeding fat on nutrient digestion in cannulated ponies fed a forage diet

Horse diets are often supplemented with dietary fat to increase caloric intake, and although the effects of fat on fiber digestibility have been studied, this research has not included the use of cannulated subjects. A decrease in fiber digestibility due to fat would be detrimental to equine performance, and thus, the current study utilized cannulated ponies as an equine model for any effects on fiber digestibility due to supplemental dietary fat on a forage diet. Five Shetland/hackney pony mares with an ileal and cecal cannula were fed hay, 2 kg/d alfalfa pellets and vegetable oil at 0, 5, 10 or 15% of total diet. Experimental diets were fed twice a day at 0600 and 1600 hours. Ponies were allowed a 14-d diet adjustment period, after which ileal and cecal cannula samples and fecal grab samples were collected at 1, 3 and 5 d post diet adjustment. On day 1, samples were taken at 0, 90, 180, 270 min and 7 and 10 h. Day 3 samples were taken at 30, 120, and 210 min, and 5 and 8 h. On d 5 samples were taken at 60, 150, and 240 min and 6 and 9 h post feeding. Samples were analyzed for crude protein, fat, acid-detergent fiber, acid-detergent lignin, and apparent digestibility of dry matter, crude protein, fat, and acid-detergent fiber. No effects were found on fiber digestibility due to fat supplementation up to 15% of the total diet in a pony model (P > 0.1). Results indicated that equine diets could be supplemented with up to 15% of fat in the form of vegetable oil to increase digestible energy with no negative impact on fiber digestibility. Correspondence to: Molly Nicodemus, Department of Animal and Dairy Sciences, Box 9815, Mississippi State University, Mississippi State, Mississippi 3976, United States; Phone: 662-325-9271; Fax: 662-325-8873; E-mail: mnicodemus@ads.msstate.edu

A novel surgical methodology for dual cannula placement of the ileum and cecum in equids: Assessment of post-operative management and clinical outcome

&NA; Cecal and ileal cannulations have previously been used to determine equine digestibility and define gastrointestinal physiology. However, research has been limited to specific portions of the equine digestive tract lacking utilization of dual cannulations. The purpose of this study was to develop and implement surgical and preoperative and postoperative procedures for cannulation of dual sections, ileum and cecum, of the equine digestive tract including development of recommendations for addressing postsurgery complications. A total of 8 ponies went through surgical procedures for the placement of a cannula at the ileum and cecum. All ponies awoke from the surgery and stood, but during postsurgical care, complications arisen including increased temperature, dehydration, lameness, herniation, and peritonitis. The survival rate of dual cannulation of the ileum and cecum was 63% of the animals with euthanization attributed to intestinal herniation. This research provides information for the academic community to better plan and implement dual cannulation of equids.