Pepperberg IM, Garcia SE, Jackson EC, & Marconi S. (1995). Mirror use by African Grey parrots (Psittacus erithacus). J. Comp. Psychol., 109, 182.
|
Russon AE, & Galdikas BMF. (1995). Constraints on great apes' imitation: model and action selectivity in rehabilitant orangutan (Pongo pygmaeus) imitation. J. Comp. Psychol., 109, 5.
|
Yamakoshi G, & Sugiyama Y. (1995). Pestle-pounding behavior of wild chimpanzees at Bossou, Guinea: a newly observed tool-using behavior. Primates, 36, 489.
|
Visalberghi E, Fragaszy DM, & Savage-Rumbaugh ES. (1995). Performance in a tool-using task by common chimpanzees (Pan troglodytes), bonobos (Pan paniscus), an orangutan (Pongo pygmaeus), and capuchin monkeys (Cebus apella). J. Comp. Psychol., 109, 52.
|
Anderson B. (1995). Dendrites and cognition: A negative pilot study in the rat. Intelligence, 20, 291–308.
|
Laughlin N.K., Lasky R.E., Luck M.L., Kluender K.R., & Hecox K.E. (1995). Early lead exposure alters behavioral and electrophysiological indices of auditory processing in the rhesus monkey. Neurotoxicology and Teratology, 17, 374.
|
Hinchcliff, K. W., Kohn, C. W., Geor, R., McCutcheon, L. J., Foreman, J., Andrews, F. M., et al. (1995). Acid:base and serum biochemistry changes in horses competing at a modified 1 Star 3-day-event. Equine Vet J Suppl, (20), 105–110.
Abstract: We examined the effects of participation in each of 3 modifications of Day 2 of a 3-day-event on blood and serum variables indicative of hydration, acid:base status and electrolyte homeostasis of horses. Three groups of horses – 8 European (E) horses and 2 groups each of 9 North American horses performed identical Days 1 (dressage) and 3 (stadium jumping) of a 3-day-event. E horses and one group of the North American horses (TD) performed modifications of Day 2 of a 1 Star 3-day-event and the other group of North American horses (HT) performed a Horse Trial on Day 2. Jugular venous blood was collected from each horse on the morning of Day 2 before any warm-up activity, between 4 min 55 s and 5 min 15 s after Phase D and the following morning. Eight E horses, 5 TD horses and 8 HT horses completed the trials. There were few significant differences in acid:base or serum biochemistry variables detected among horses performing either 2 variations of the Speed and Endurance day of a 1 Star 3-day-event, or a conventional Horse Trial. Failure to detect differences among groups may have been related to the low statistical power associated with the small number of horses, especially in the TD group, variation in quality of horses among groups and the different times of the day at which the E horses competed. Differences detected among time points were usually common to all groups and demonstrated metabolic acidosis with a compensatory respiratory alkalosis, a reduction in total body water and cation content, and hypocalcaemia. Importantly, horses of all groups did not replenish cation, chloride, and calcium deficits after 14-18 h of recovery.
|
Holmstrom, M., Fredricson, I., & Drevemo, S. (1995). Biokinematic effects of collection on the trotting gaits in the elite dressage horse. Equine Vet J, 27(4), 281–287.
Abstract: Trot in hand, working trot, collected trot, passage and piaffe of 6 Grand Prix dressage horses were recorded by high speed film (250 frames/s). Angular patterns and hoof trajectories of the left fore- and hindlimbs were analysed and presented as mean and standard deviation (s.d.) curves. Speed and stride length decreased and fore- and hind stance phase durations increased with collection resulting in no suspension in piaffe. The diagonal advanced placement was positive in all gaits except for piaffe. Most of the changes in forelimb angular patterns were effects of reduction in forelimb pendulation. The horses did not step under themselves more in collected trot, passage and piaffe than in trot in hand. The stifle and hock joints were more flexed at the start of the stance phase in piaffe and passage than in the other gaits. Flexion of the hock joint at the middle of the stance phase was largest in passage and piaffe. In spite of the limited number of horses the present study confirmed earlier observations of conformation and gaits in dressage horses. Hindlimb pendulation, femur and pelvis inclinations and elbow, carpal, stifle and hock joint angles seem to be the most significant angular measurements for dressage performance.
|
Clayton, H. M. (1995). Comparison of the stride kinematics of the collected, medium, and extended walks in horses. Am J Vet Res, 56(7), 849–852.
Abstract: Six horses, highly trained for dressage competition, were used to study the stride kinematics of the walk, and to compare the kinematics of the collected, medium, and extended walks. Horses were filmed in a sagittal plane at a rate of 150 frames/s; temporal, linear, and angular data were extracted from the films. Results of ANOVA and Duncan's multiple range test indicated that the speed of the collected walk (1.37 m/s) was significantly (P < 0.01) slower than that of the medium (1.73 m/s) and extended (1.82 m/s) walks, values for which were not significantly different from each other. The increase in speed was associated with a significant increase in stride length, from 157 cm in the collected walk to 193 cm in the extended walk. This was a result of an increase in the over-tracking distance, whereas there was no significant difference in the distance between lateral placements of the limbs. Stride duration decreased (P < 0.01) from the collected walk (1,159 ms) to the extended walk (1,064 ms). Angles of the metacarpal and metatarsal segments, measured on the palmar/ plantar aspect, were higher at impact and lower at lift off in the collected than in the extended walk (P < 0.01). This indicated greater range of angular motion of this segment during the stance phase in the extended walk. Only 1 of the 6 horses had a regular 4-beat rhythm of the footfalls, with equal time elapsing between the lateral and diagonal footfalls.
|
Barnes, H. G., Tucker, R. L., Grant, B. D., Roberts, G. D., & Prades, M. (1995). Lag screw stabilization of a cervical vertebral fracture by use of computed tomography in a horse. J Am Vet Med Assoc, 206(2), 221–223.
Abstract: A traumatic fracture of C2 was diagnosed radiographically in a 1-year-old German Warm-blood stallion. Fracture configuration was difficult to see on survey radiographs. Computed tomography yielded a more accurate assessment of the fracture and facilitated fracture repair with cortical lag screws. Precise screw placement, to avoid spinal cord damage, was obtained by use of computed tomography. Follow-up radiography revealed normal bone healing, and the horse was in dressage schooling 24 months after surgery.
|