Deborah Goodwin

Paedomorphosis affects agonistic visual signals of domestic dogs

Many of the structural modifications of modern breeds of domestic dog,Canis familiariscan be explained by changes in the rate of development, during domestication from the wolf,C. lupusThese changes have been dominated by paedomorphosis, or underdevelopment, so that the adult passes through fewer growth stages and resembles a juvenile stage of its ancestor. In this paper the effects of these processes on the signalling ability of 10 breeds selected for their degree of physical dissimilarity to the wolf are examined. The number of ancestral dominant and submissive behaviour patterns used during signalling within single-breed groups ranged from two (Cavalier King Charles spaniel) to 15 (Siberian husky), and this correlated positively with the degree to which the breed physically resembles the wolf, as assessed by a panel of 14 dog behaviour counsellors. When the signals displayed by each breed were grouped according to the stage of wolf development in which they first appear, those breeds with the smallest repertoires were found to draw most of their signals from those appearing before 20 days of age in the wolf, suggesting that physical paedomorphism has been accompanied by behavioural paedomorphism.

Food selection by the domestic cat, an obligate carnivore.

The domestic cat Felis silvestris catus is the most accessible member of the family Felidae for the study of the relationship between food selection and nutrition. In contrast to pack-living animals such as the dog, and opportunistic omnivores such as the rat, the cat is generally able to maintain its normal body weight even when allowed ad libitum access to palatable food by taking small meals and adjusting intake according to the energy density of the food(s) available. The most extreme adaptations to carnivory discovered to date lie in the taste buds of the facial nerve, which are highly responsive to amino acids and unresponsive to many mono- and disaccharides. Preferences for particular foods can be modified by their relative abundance, their novelty, and by aversive consequences such as emesis: the mechanisms whereby these are brought about appear to be similar to those used by omnivorous mammals.

Is there evidence of learned helplessness in horses

Learned helplessness is a psychological condition whereby individuals learn that they have no control over unpleasant or harmful conditions, that their actions are futile, and that they are helpless. In a series of experiments in which dogs were exposed to inescapable shocks, this lack of control subsequently interfered with the ability to learn an avoidance task. There is evidence that both neural adaptations and behavioral despair occur in response to uncontrollable aversive experiences in rodents, although this has yet to be demonstrated in other species such as horses. However, certain traditional methods of horse training and some behavioral modification techniques—it has been suggested—may involve aversive conditions over which the horse has little or no control. When training and management procedures are repeatedly unpleasant for the horse and there is no clear association between behavior and outcome, this is likely to interfere with learning and performance—in addition to compromising welfare. This article reviews published literature and anecdotal evidence to explore the possibility that the phenomenon, learned helplessness, occurs in the horse.

A survey of the behavioural characteristics of pure-bred dogs in the United Kingdom

One-hundred-and-twelve small animal veterinarians and 56 dog care professionals were asked to rate the behavioural characteristics of 49 breeds of dog, and to compare males and females by means of a 13-point questionnaire. From their replies, factor analysis was used to extract three underlying traits, labelled aggressivity, reactivity and immaturity. On the basis of these traits, eight groups of breeds were derived. Membership of these groups did not correspond exactly with any of the four existing breed classification systems (Mégnin, the Fédération Cynologique International, ancient breeds and Kennel Club of Great Britain), but significant differences between Kennel Club groups were found on all three traits. Male dogs were rated higher than females on both aggressivity and immaturity; the components of reactivity were also rated higher in males, apart from the demand for affection which was rated higher in females. Females were also considered easier to train than males.

Impaired instrumental choice in crib-biting horses (Equus caballus)

Horses displaying an oral stereotypy were tested on an instrumental choice paradigm to examine differences in learning from non-stereotypic counterparts. Stereotypic horses are known to have dysfunction of the dorsomedial striatum, and lesion studies have shown that this region may mediate response-outcome learning. The paradigm was specifically applied in order to examine learning that requires maintenance of response-outcome judgements. The non-stereotypic horses learned, over three sessions, to choose a more immediate reinforcer, whereas the stereotypic horses failed to do so. This suggests an initial behavioural correlate for dorsomedial striatum dysregulation in the stereotypy phenotype.

Comparison of Polar ® heart rate interval data with simultaneously recorded ECG signals in horses

Human heart rate monitors (HRMs) are frequently used in equine studies to measure heart rate (HR) and interbeat intervals (IBIs). However, to date, the most commonly used HRM (the Polar® system) in horses has not been validated against simultaneously recorded electrocardiogram (ECG) signals during a range of ambulatory conditions. Polar® S810i and ECG IBIs were simultaneously recorded from six horses under three conditions commonly included in behavioural observation: standing at rest, loose in the stable and at liberty in a field. Following recording, Polar® IBI data were corrected for error processing in cardiac data. Corrected and uncorrected Polar® data were then compared with simultaneously recorded ECG data using a variety of commonly measured time and frequency domain parameters (e.g. HR variability (HRV)). Polar® data collected while horses were stabled or in the field were significantly different from ECG data, even following correction of the data, and therefore, it may not be possible for the two systems to be used interchangeably. This study indicates the need for caution while using Polar® S810i for collecting HRV data, unless horses are stationary, and even when the IBI data are corrected for measurement error.

Preliminary investigation of morphological differences between ten breeds of horses suggests selection for paedomorphosis.

Paedomorphosis is the retention of juvenile morphology at maturity and is important in generating evolutionary change in domestic species and species in the wild. When comparing dogs with the wolf, this preliminary study saw paedomorphosis in their physical and behavioral traits (Goodwin, Bradshaw, & Wickens, 1997). This preliminary study compared morphological characteristics of 10 breeds from northern regions (Shetland ponies) and southern regions (Arabians) with the Exmoor pony. Twenty-three respondents from the United Kingdom and Australia rated the breeds for 7 physical traits. As evidenced by low standard deviations, the respondents demonstrated a high degree of agreement. The study ranked breeds from the most similar (Highland pony) to the least similar (Arabian) to the Exmoor pony. The least similar breeds had physical traits suggestive of paedomorphosis: small heads, long legs, and a low head-to-body ratio. This preliminary study suggests that morphological, behavioral, and physiological differences between the breeds-plus morphometric comparisons of extant breeds and faunal remains of predomestication horses-warrant further study.

Equitation Science: The Application of Science in Equitation

Equine ethology, management, learning theory, skill, and talent combine to influence numerous outcomes in horse-rider interactions. The welfare of ridden horses merits scientific scrutiny because horses are largely trained using negative reinforcement and are required to respond to pressure-based signals rather than work for positive rewards. In the lay equestrian literature, the use of light aids (signals or cues) and the minimal use of punishment are highly regarded. However, as illustrated in work presented at the first International Equitation Science Symposium (2005), dressage judges struggle to identify light rein tensions (de Cartier d’Yves & Odberg, 2005).

The International Society for Anthrozoology (ISAZ) 13th Annual Conference: 6th October 2004 “Advances in the Science and Application of Animal Training”

This special issue contains nine peer-reviewed papers based on oral presentations given at the meeting, plus 22 refereed abstracts of the meetings oral and poster presentations, as published record and resource for organizations, academics and students. The articles discusses the importance of training for the improvement of husbandry, management and welfare of companion, farm, zoo and laboratory animals.