Abstract: We investigated 8 horses in five therapeutic riding centres situated in San Cataldo (Caltanissetta – I), Nicosia (Catania – II), Pellaro (Reggio Calabria – III), San Gregorio (Catania – IV), Niguarda Hospitals (Milan – V). The managements of the animals were of different typologies: Type 1, Type 2 and Type 3. In type 1 the horses were used for therapeutic riding only. Furthermore intra and interspecific social interactions were not allowed. In type 2 the horses played kinetic activities and made social interactions. In type 3 the horses were free in paddock, as intra and interspecific social interactions were allowed. The centre I, with a management of type 1, housed 1 horse (A1); the centre II, with a management of type 2, housed 1 horse (B2); the centre III, with a management of type 1, housed 1 horse (C1); the centre IV, with a management of type 2, housed 2 horses (D2 and E2); the centre V, with a management of type 3, housed 3 horses (F3, G3 and H3). Breeds of horses were: Anglo-Arab (n°1), Avelignese (n°3), Italian Selle (n°3), draught-horse crossbreed (n°1). They were 2 geldings and 6 females. Their ages ranged from 12 to 23 years. We observed a total of 64 patients affected by different pathologies: autism, motory handicap, blindness and deafness, children“s cerebral paralysis, relational problems, mental deficiency, Down”s syndrome.
The horses" behaviour was observed at rest and during therapeutic activities with these patients. The Heart Rate (HR) was used as physiological parameter for an ethological evaluation, measured by a telemetric heart rate monitor (Polar Horse Trainer). Horses were analysed with a reactivity test for emotional homeostasis evaluation, too. Heart rate values were studied with non parametrical statistical analysis methods.
Distinct management typologies provided statistically different basal mean values of heart rate (intergroup and intragroup): Type 1 vs Type 2 (P~0.05) and Type 1 vs Type 3 (P<0.05). The comparison of heart rate during therapeutic activities of diverse management showed the following results: A1 vs B2 (P<0.05), B2 vs C1 (P<0.05), Type 1 vs Type 2 (P<0.01). Different managements, both in the same or different typologies, gave significantly diverse results (A1 vs E2: P~0.05; C1 vs E2: P~0.05; B2 vs E2: P~0.05).
This study shows that the statistic differences obtained by therapies with autistic patients derive from management conditions of Type 1. In reactivity test there aren"t any significant differences among the three management typologies. However, we recorded strong variation between medium and maximum values of heart rate, especially in Type 1 and Type 2 of management.
These high variations of heart rate indicated fear reaction of the horse to new stimuli.
This reaction could lead to dangerous accidents for patients during therapeutic activities.
Horses used in therapeutic riding programs must be evaluated before this employment. Horse's behaviour can be assessed by an ethological observation and a reactivity test. Furthermore, the horses must be guaranteed welfare conditions and must live in an environment enriched with sensorial stimuli and respectful of their physiological and ethological needs.

Abstract: Variation in the control region and the 12S rRNA gene of all surviving mitochondrial lineages of Przewalski's horse was investigated. Variation is low despite the present day population being descended from 13 individuals probably representing animals from three different regions of its range. Phylogenetic comparison of these sequences, with sequences for the domestic horse, does not resolve the ancestral status of either horse.

Abstract: Injuries to the superficial digital flexor tendon are common in horses required to gallop and jump at speed. Partial rupture of this tendon usually occurs in the central core of the midmetacarpal region and may be preceded by localised degenerative changes. Post mortem examination of apparently normal equine flexor tendons has revealed an abnormal macroscopic appearance in the central core, characterised by a reddish discolouration. We have previously shown that there is also physical damage to the collagen fibres. In the present study we tested the hypothesis that the abnormal appearance is accompanied by changes in the composition of the extracellular matrix of the tendon. Biochemical analysis of the extracellular matrix demonstrated an increase in total sulphated glycosaminoglycan content, increase in the proportion of type III collagen and decrease in collagen linked fluorescence in the central core of 'degenerated' tendons relative to tissue from the peripheral region of the same tendon. Dry matter content and total collagen content were not significantly different between tendon zones or normal and 'degenerated' tendons. These changes suggest a change in cell metabolism and matrix turnover in the central core of the tendon and are likely to contribute to a decrease in mechanical properties in this part of the tendon, predisposing to the characteristic partial rupture of the tendon.

Abstract: The social behavior of feral horses was studied in the western United States. Stable harem groups with a dominant stallion and bachelor hermaphrodite hermaphrodite groups occupied overlapping home ranges. Groups spacing, but not territoriality, was expressed. Harem group, stability resulted from strong dominance by dominant stallions, and fidelity of group members. Eliminations of group members were usually marked by urine of the dominant stallion. Hermaphrodite-hermaphrodite aggression involved spacing between harems and dominance in bachelor groups. Marking with feces was important in hermaphrodite-hermaphrodite interactions. Foaling occurred in May and early June, following the post-partum estrous. All breeding was done by harem stallions. Young were commonly nursed through yearling age. These horses showed social organizations similar to other feral horses and plains zebras.

Abstract: This study investigated the effect of lidocaine i.v. on halothane minimum alveolar concentration (MAC) in ponies. Six ponies were anaesthetised with thiopentone and succinylcholine, intubated and anaesthesia maintained with halothane. Ventilation was controlled and blood pressure maintained within clinically acceptable limits. Following a 2 h equilibration period, baseline halothane MAC was determined. The ponies were then given a loading dose of lidocaine (2.5 or 5 mg/kg bwt) or saline over 5 min, followed by a constant infusion of lidocaine (50 or 100 microg/kg/min, or saline, respectively). The halothane MAC was redetermined after a 60 min infusion of lidocaine or saline. The baseline halothane MAC for the control group was mean +/- s.d. 0.94 +/- 0.03%, and no significant decrease occurred following saline infusion. Lidocaine decreased halothane MAC in a dose-dependent fashion (r = 0.86; P < 0.0003). The results indicate that i.v. lidocaine may have a role in equine anaesthesia.