Abstract: A preference test was used to demonstrate that gilts have the ability to associate two sets of neutral cues with two different periods of confinement and water deprivation and to anticipate the long-term consequences of their choice in the test. Twelve gilts housed in two large, straw-bedded pens were trained to go to two sets of 12 crates, positioned on each side of a choice point, for feeding twice a day. Following initial training, the two sets of crates were marked with contrasting visual patterns and the patterns were associated with either 30 min (`short' confinement) or 240 min (`long' confinement) of confinement in the crates after entry. During 16 days of preference testing, the gilts were sent alternately to one side or the other in the mornings and allowed to choose in the afternoons. Eight gilts chose the short confinement side more often, two, the long confinement side more often and two, each side an equal number of times, indicating that most gilts learned the association and preferred to be released shortly after feeding. However, gilts still chose the long confinement side on occasion, suggesting that they did not find 240 min of confinement very aversive. When the gilts were sent to the crates in the morning, their behaviour indicated that they expected to be released or confined depending on which crate they were in. The cognitive abilities of animals with respect to perception of time and anticipation of future events have important implications for their welfare. This study demonstrates that methods can be developed to ask animals about such things.

Abstract: Awareness varies between different species and humans can never truly appreciate what it is like to be another individual, either of the same species or another. Visual perceptual faculties provide some evidence of the extent to which domesticated animals derive information from objects in their environment, whilst changes in behaviour resulting from different visual stimuli can also provide valuable information on the state of visual awareness. Extensive processing of potentially visual information must occur in all domesticated species, but is much less well understood than purely sensory based information. For example, sensory aspects of colour vision are reasonably well understood, but the role of wavelength variables in an animal's cognition and its colour experience is not clear. Considerable use is made of diurnal changes in photoperiod to synchronise endogenous rhythms to particular times of the day and the year. Variation in light intensity in natural images is also important for social reasons for animals to be able to discriminate between, e.g., different faces, but little is known about intensity preferences or the effects of intensity on behaviour. It appears likely that in many cases visual stimuli represent some of the most important influences on an animal's awareness, either alone or in combination with, e.g., olfactory cues. However, a much greater understanding of their processing is required before we can make useful deductions about visual awareness in domesticated animals.

Abstract: Feeding and training may affect acid-base responses to strenuous exercise. Acidosis usually correlates with higher blood lactate concentrations during intense exercise, but alkalosis has been found in several studies of horses, and higher lactate responses during sprints have been found in fat adapted horses. To elucidate these unexpected findings, we applied a comprehensive physicochemical approach to evaluate acid-base responses during exercise in fat adapted horses. In incremental tests and repeated sprints, changes in blood [H+] were dependent upon corresponding changes in pCO2 but not strong ion difference (SID, the algebraic sum of ions of sodium, potassium, chloride and lactate). The influence of changes in [Lac-] were largely offset by changes in [Na+], [K+] and [Cl-], so that SID was unchanged and did not contribute to the exercise induced acidemia, so it may be inaccurate to term this a lacticacidosis. During repeated sprints, central venous [H+] increased (acidosis) but arterial [H+] decreased (alkalosis). These changes were consistent with concurrent changes in venous and arterial pCO2 but not SID. Fat adaptation decreased mixed venous pCO2 during repeated sprints, which is consistent with the lower respiratory quotient associated with fat oxidation. Less pulmonary work to eliminate CO2 could benefit horses under hot and humid conditions, especially those with mildly reduced pulmonary function. The blood lactate response was decreased during aerobic tests but increased during anaerobic tests on fat adapted horses. Fat adaptation appears to facilitate the metabolic regulation of glycolysis, by sparing glucose and glycogen at work of low intensity, but by promoting glycolysis when power is needed for high intensity exercise. The blood lactate response to repeated sprints was increased more by the combination of fat adaptation and oral supplementation of sodium bicarbonate than by the sum of the responses to fat alone or bicarbonate alone. This synergism suggests that need for further studies of the interaction of fat adaptation with dietary cation-anion balance, especially under hot conditions. These results integrate harmoniously with previous findings of lower feed intake and fecal output, lower loads of heat and CO2, lower water losses in the feces and by evaporation, and less spontaneous activity and reactivity in fat adapted horses. Thus fat adaptation confers several advantages on horses and presumably other equids used for hard work, especially in the heat.

Abstract: This study examined the ability of two adult white rhinoceroses (Ceratotherium simum simum) to develop a visual discrimination between an open circle and a triangle. These stimuli were presented as black symbols on large white cards. The cards were presented 4.6 m apart and a food reward was given if the subject approached the open circle. Ten discrimination choices were given daily until each subject reached the criterion of 80% correct responding over a block of 50 trials. The female reached the criterion over trials 151–200, while the male required considerably longer (trials 501–550). The male's discrimination was dramatically affected by a shift in the food reward. This study demonstrates that these rhinos were able to develop a successful discrimination and this protocol could be used to further examine their visual acuity.