The effect of orientation during trailer transport on heart rate, cortisol and balance in horses

Abstract Sixteen same-sex pairs of Quarter Horse and Quarter Horse-cross yearlings (eight pairs during each of two trials, 1 year apart) were transported for 17.8 ± 0.52 min over a standard course with one horse facing in the direction of travel and one facing the opposite direction. The orientation of the horses in each trial was alternated with respect to the side of the trailer (float). Heart rates were monitored continuously using a strip chart recorder and were determined for the following events during each trip: (1) after the horses were loaded, but just prior to beginning the trip; (2) immediately after the initial movement of the trailer; (3) during travel over smooth roads near the start and near the end of the trip; (4) before and after an abrupt stop; (5) the mean for the entire trip. During the second trial, plasma concentrations of cortisol and thyroxine (T 4 ) were determined in blood samples taken via jugular puncture in the holding paddock prior to any handling beyond catching, in the trailer prior to hauling and in the trailer immediately after the trip. Observers riding inside the trailer recorded how often the horses impacted the sides and ends of the trailer, lost their balance, pawed, vocalized or defecated. Rear facing horses had fewer side and total impacts and losses of balance( P P P

[1]  J. Kent,et al.  The effect of road transportation on the blood constituents and behaviour of calves. II. One to three weeks old. , 1986, The British veterinary journal.

[2]  T. Nett,et al.  Effect of transportation on the estrous cycle and concentrations of hormones in mares. , 1990, Journal of animal science.

[3]  R. Reíd,et al.  Studies on the carbohydrate metabolism of sheep. XIV. The adrenal response to psychological stress , 1962 .

[4]  S. Creer.  Alleviating road transit stress on horses , 1981 .

[5]  V. James,et al.  Adrenocortical function in the horse. , 1970, The Journal of endocrinology.

[6]  B. Hetzel,et al.  EFFECT OF EMOTIONAL STRESS AND TSH ON THYROID VEIN HORMONE LEVEL IN SHEEP WITH EXTERIORIZED THYROIDS. , 1964, Endocrinology.

[7]  G. Codazza,et al.  Serum enzyme changes and haemato-chemical levels in thoroughbreds after transport and exercise , 1974 .

[8]  J. Fullerton,et al.  Effects of transportation, surgery, and antibiotic therapy in ponies infected with Salmonella. , 1983, American journal of veterinary research.

[9]  S. Levine.  A definition of stress , 1985 .

[10]  Sharon E. Cregier,et al.  Reducing equine hauling stress: A review , 1982 .

[11]  E. Squires,et al.  Effects of transportation on early embryonic death in mares. , 1990, Journal of animal science.

[12]  J. Kent,et al.  The effect of road transportation on the blood constituents and behaviour of calves. III. Three months old. , 1983, The British veterinary journal.

[13]  D. Love,et al.  Influence of head posture on the respiratory tract of healthy horses. , 1990, Australian veterinary journal.

[14]  R. Dantzer,et al.  Stress in farm animals: a need for reevaluation. , 1983, Journal of animal science.

[15]  M. Fowler.  Restraint and handling of wild and domestic animals , 1980 .