Abstract: For ages horses and donkeys constituted the most important domesticated animals. Even though equids were often bred and kept in close proximity to humans, surprisingly little is known about their cognitive abilities. Traditionally, horses are not regarded as clever animals; common beliefs maintain that the horses“ behaviour is merely driven by conditioned-responses. Additionally, from an anthropomorphic point of view donkeys are believed to be ”stupid" animals.
Our study investigates the equids“ ability to recover a hidden object. For this purpose the animal has to create and maintain a representation of the object and its location in space, from the moment in which it disappears from direct perception, till the moment in which it reappears. The knowledge about objects being entities that continue to exist even when they are no longer available for direct perception is refered to as the well known concept of ”object permanence".
We primarly assessed the ability of Esperia's pony and donkeys to solve a Detour problem while employing an opaque “U-shaped” barrier. Each animal observed a food bucket moving and disappearing behind the barrier. Immediately after the object"s disappearance, the animal was released to search for the object. If it solved the task by detouring the barrier it was positively reinforced.
The ability to retain in memory the hidden object as well as its spatial location was subsequently tested in the presence of two, rather than one, screens (Working Memory testing phase). The food bucket was made to move and hidden behind one of the two identical screens, while the animal was watching it. Following a pre-established delayed period of 10 sec, the animal was set free to look for the food. In such a test the detour problem is combined with the classical delayed-response task, which is in use for the comparison of memory duration in different species.
In order to recover the hidden objects, animals must encode, maintain and correctly regain from their working memory the existence of the no longer visible object and its location from their working memory.
Both donkeys and ponies performed the Detour task showing to grasp the fact that an object which is no longer perceivable still continues to exist and can be regained. They also were able to correctly retrieve the goal object after a delay of 10 s in the Working Memory tasks, showing that they had encoded, maintained and correclty retrieved from their working memory the spatial location of the hidden object as well as its existence.
Nevertheless, when Standardbreds, raised in traditional stables, were tested in identical conditions to those describe for the ponies and donkeys, they could not succeed in the Detour tasks. The reason for such differences needs to be studied Even though it would be interesting to focus on handling differences, i.e., the ponies had been living in an environment rich in natural stimuli, while the Standardbreds had lived in a man-controlled environment since birth. It is also noteworthy that, like donkeys, the Esperia's pony have a reputation for being hard to handle.
Several considerations could arise from our preliminary investigations, and we will have the pleasure to leave them open for discussion.

Abstract: A number of studies have demonstrated that horses have chromatic vision and are able to distinguish colours from grey, independent of brightness. Anatomical and physiological data support the view that they are dichromats. In two experiments we provide behavioural evidence for their dichromacy. In the first we measured photopic spectral sensitivity. Using a spatial two alternative forced choice task, two horses were required to discriminate a coloured circular patch on an achromatic background from a blank field over a range of wavelengths . The obtained spectral sensitivity function was consistent with the presence of two cone classes with predicted spectral peaks at 429 nm and 545 nm, respectively. In the second experiment we obtained wavelength discrimination functions. The same animals were required to make discriminations between a series of standard wavelengths and a series of comparison wavelengths across the spectrum. The resultant wavelength discrimination function showed a single minimum at approximately 480 nm, which is also consistent with the view that horses are dichromats. Key Words: Horse, colour vision, spectral sensitivity, wavelength discrimination

Abstract: Cribbiting is a common stereotypy in domestic horses and is associated with stress and low fibre/high concentrate diets, which are known to cause gastric inflammation and ulceration. Recent studies indicate that antacid supplements can reduce both gastric inflammation and cribbiting. However, stereotypies are also associated with altered brain functions and these are thought to be responsible for emancipation. Emancipation refers to a process by which stereotypies become increasingly independent of the causal factors and may therefore persist with age, regardless of the conditions. Emancipation complicates therapy and points to the importance of prevention.
To further examine the relationship between gastric health and cribbiting and its relation to age at onset, we examined the effect of the proton-pump inhibitor omeprazole (GastroGard, Merial) on gastric inflammation/ulceration and on cribbiting in a double-blind placebo-controlled study. Thirty-one horses of different sex, breed and age were randomly allocated to treatment and placebo and divided into three groups depending on age: 0-5 years (n=11), 5-10 years (n=11) and >10 years (n=9), whereby age at onset of cribbiting was ≤ 5 years for all horses. Treatment and placebo were administered orally by syringe once every day for 28 days by the horse owners. Treatment consisted of 4mg/kg omeprazole for the first four days and 1mg/kg for the following 24days.
Using scan sampling and behaviour sampling, general activity and the number of crib-bites were assessed in the home pens one day before and one day between day 21 and 28 of treatment. Observations were made for three hours each around morning and evening feeding times, respectively. Prior to pre-treatment observations and after post-treatment observations, the horses were transported to the clinic and endoscoped for signs of inflammation and ulceration in the oesophagus, the squamous area, the glandular area and the first part of the duodenum using a common scoring system (Andrews et al. 1999).
All 31 horses showed signs of gastric inflammation/ulceration which decreased significantly from a median score of 1,2 to 0,6 in the treatment group (Wilcoxon signed rank test, z=-3,186, p=0,001), while there was no change in the placebo group (z=-0,577, p=1.0). However, there was no significant difference in cribbiting before and after treatment, neither in the treatment group (z=-1,834, p=0,068), nor in the placebo group (z=-0,415, p=0,734). Moreover, there were no significant effects of age on gastric inflammation/ulceration (2-way ANOVA, F=1,112, p=0,345) or cribbiting (F=1,113, p=0,344).
These results contrast with the recent studies on the effects of antacids on gastric health and cribbiting. There are two possible explanations for this: First, cribbiting may become rapidly established and may thus have persisted even in the youngest age group. Second, omeprazole acts specifically by reducing gastric acid secretion into stomach, while antacids may also have an effect on the intestine. However, these results shed doubts on the hypothesis that cribbiting is caused by gastric inflammation/ulceration.

Abstract: The human-horse relationship forms an essential component in the diversity of todays use of horses. The reactions of horses to interactions with humans are mostly the result of interplay between their own temperament; the temperament and skills of the human and their previous experience – with humans. Moreover, the understanding of the human-horse relationship may improve the welfare of horses and humans. Nowadays, “sympathetic” training methods are gaining tremendous attention of horse owners. In the “sympathetic” training method the focus lies on the use of body language in human-horse communication, as well as respecting the horses natural needs. With 28 horses the effect of a “sympathetic” training method versus a conventional training method on the horse“s response on a human-approach test was studied. Fourteen horses of 3.5 years of age were subjected to a five week training period with a conventional training method, the other fourteen horses were subjected to a ”sympathetic“ training method. The overall frequency of snorting during the human approach tests decreased on average from 4.4 (± 1.1) before the training period to 3.1 (± 0.9) after the training period (both groups). However, there was a significant (p=0.006) difference between training methods: the horses trained in the ”sympathetic“ method decreased snorting by 4.3 (±1.1) while the horses trained in the conventional method increased with 1.5 (±0.9). While horses trained in the conventional method whinnied less in the second human approach test, horses trained in the ”sympathetic“ method whinnied more after the period of training. This difference was found to be significant (p=0.006). Defecating decreased over time, but was not different between training methods. The frequency of touching the unfamiliar handler increased over time for both training methods. The horses trained in a conventional method increased from 1.5 to 2.5 and for the sympathetic trained horses from 1.9 to 3.7. This increase was not significantly different for the training methods. Heart rate showed a minor decrease between the human approach tests (before training period 85.3 bpm, after training period 74.3 bpm) but there were no significant differences between training methods. Similarly, there was a slight increase in heart rate variability (rmssd: from 37.0 to 45.2), but no significant differences between training methods. Overal it was concluded that horses trained with this ”sympathetic“ method tended to be more trustful and less stressful in the presence of an (unfamiliar) human compared to horses trained with a conventional method. This may have been due to reduced stress during horse-human contact in the ”sympathetic" training method used. The long term effects on the welfare of the horses, still needs to be investigated.

Abstract: According to Interpersonal Theory every interaction is motivated by efforts to achieve and maintain self-esteem and to avoid anxiety. People"s characteristic ways of accomplishing these ends are called interpersonal reflexes. Those interpersonal reflexes are evident in interaction with animals, since they are determined by the interpersonal traits of personality. We wanted to catch the typical interpersonal reflexes in between humans and horses compared to pet animals.
We used the self rating assessment instrument “Inventory of Problematic Interactions with Animals” (IPI – Animals), which bases on a Interpersonal Circumplex Model (Human Animal Circumplex; HAC) and was constructed to catch specific dispositions of distress caused by animals using two dimensions (too dominant vrs too submissive and too warm versus too cold). Data of 233 male adolescents (93 of them actual pet owners, from that 12 horse owners) were collected.
We found that different pet preferences holds distinct locations in the HAC. Horse persons differ from dog and cat persons within the dimension dominance (dog: chi2(df126) =161.54 p= .018; cat: chi2(df126) =199.95 p= .045). Persons, who own a horse or would wish to own one, describe themselves as dominant, but warm interactors. They report that they want horses to notice them. They tend do too much for them and behave very effusively with them. On the other hand they feel that the animal takes too much advantage of the relationship.