Abstract: The social behaviour of two groups of Merino ewes and one group of Merino x Border Leicester ewes was studied. Each group comprised eight sheep, 15 months of age and, within each group, the animals were of similar liveweight. Dominance rankings were established at each test, but there was little consistency in ewe rank over time. Similarly, little consistency was found in ewe ranking for movement order between pens, and for exploratory and fear test rankings. However, with tests on movement orders, some consistency in the sheep which ranked first was shown. In the field, no aggression was seen while sheep were grazing and there were no occasions when ranking related to movement could be observed. There were short-term associations between pairs of sheep, but these occurred in less than half the individuals. Although the spatial distribution was not studied, the lack of long-term association between pairs would suggest that strong spatial preference does not occur. It is concluded that the social organization of single-age Merino and Merino x Border Leicester ewes is not based on dominance or leadership ranking nor on long-term associations between individuals.

Abstract: The results of a standardised radiological examination of 5928 Hanoverian Warmblood horses selected for sale at auction were used to predict relative breeding values (RBV) in the 23,662 horses included in the last four generations of the probands' pedigrees. The distribution of the RBV was investigated in the whole four-generation pedigree, in the probands and in those stallions that contributed at least three offspring to the probands. The RBV of the probands' sires were further compared with the officially published performance-based relative breeding values, i.e., total indices dressage (TID) and jumping (TIJ). The sires' level of dressage indices was considerably higher (mean TID=110) than of the jumping indices (mean TIJ=98). Total indices radiographic findings (TIR) were calculated for the sires with varying weighting given to the individual RBV. In each case, this resulted in a mean TIR of 99. Finally, total indices were derived from TIR and TID and/or TIJ in order to develop different selection schemes for all-purpose breeding and for breeding focused on dressage and show jumping. All breeding values under consideration increased by between 1% and 19% when radiographic findings were weighted with between 30% and 60% complementary to the corresponding performance parameters, and when only sires were selected with above average total indices. At the same time, the prevalences of the radiographic findings investigated here were lowered by up to 10% each. When only one radiographic finding was considered at a time, the maximum attainable response to selection was a 16-23% increase in the relative breeding values and a relative decrease in prevalences of radiographic findings of between 31% and 52%. The results of this study indicate that it is possible in horse breeding to consider simultaneously health and performance traits. Medical data should be included in the prediction of breeding values in order to improve the radiological status of today's riding horses.

Abstract: The responses of eleven pairs of crib-biting and non-crib-biting horses (controls) to an arousal-inducing stimulus were studied. Video-observation of the horses revealed that crib-biting horses spent between 10.4 and 64.7% of their stabling time performing the stereotypy. During the first 2 days of an experimental period, the horses were conditioned to receive food from a special bucket. On the third day the food bucket was presented, but the horses were not allowed to feed. Arousal behaviour and crib-biting intensity as well as plasma cortisol concentration, heart rate (HR) and heart rate variability (HRV) were recorded at rest, and during and after presentation of the food stimulus. The stimulus induced a significant increase of HR and arousal behaviour in crib-biters and in controls, whereas the crib-biting frequency decreased. Power spectral analysis of the HRV revealed significant differences between crib-biters and controls at rest: crib-biters had a lower vagal tone (high frequency component, HF) and a higher sympathetic tone (low frequency component, LF) than controls. The lower basal parasympathetic activity might be an indication why crib-biting horses, in contrast to the controls, showed neither a significant decrease of the HF component during presentation of the food stimulus nor an increase of the HF component after presentation. Thus, there might be differences in the tuning of the autonomous nervous system and of the stress reactivity in crib-biting and in control horses. The results suggest that the crib-biting horses are more stress sensitive and physiologically and psychologically less flexible than the control horses.

Abstract: The relationship between ration and behavior in horses has not been extensively studied, though it is widely thought that the type of feed fed can influence how a horse behaves. For example rations high in sugar and starch have been documented to increase young horses' reactivity to novel stimuli. Since the temperament of a horse has been linked to the ease with which it can be trained, documenting if a horse’s behavior can be altered by its ration would be of interest to the equine industry. We hypothesized that increasing the starch intake of young mustangs by addition of corn or oats to a forage-based total mixed ration (TMR) would alter their reactivity to stimuli and responsiveness to learned commands. To test this hypothesis 8 recently tamed mustangs (4 geldings and 4 fillies, one and two years of age) were used. The mustangs were divided into two groups based on age, sex and temperament. In a series of three experiments they were fed TMR cubes with or without 10% added corn free choice (Exp. 1, Fall, 2010), or a basal ration of TMR cubes free choice with morning meals of 1kg TMR cubes versus an equicaloric amount of corn (exp. 2, Spring, 2011) or oats (Exp. 3, Spring 2011) in a simple crossover design with 2 to 2.5 week adaptation periods for each trial. The horses’ trainability and reactivity to stimuli were evaluated before the treatments were initiated and after each adaptation period 60 to 90 minutes after the morning meals were fed. In the tests the horses were asked to perform a standardized series of commands (ie: walk on, turn, stop and stand still, back up), and were then confronted with a novel stimulus, which varied with each trial. A single handler (SLR) led each horse through the tests, which was then repeated on the next day using a student handler instead. Treatments were then switched and the horses were re-tested, so that each horse was tested on each feed type in all 3 experiments. Each horse’s performance was scored by 2 judges, who were both professional trainers who had been assigned 4 horses to train throughout the study. These judges scored the horses' performances as the tests were done. Each test was videotaped for further evaluation by a third judge (D. Ramnath) who was not familiar with the horses and who was blind to the ration being fed. The performances were scored using a numerical scale of 0-5, with 0=total noncompliance and 5=perfect execution of the tasks asked of the horse. There were no differences (p>0.1) in responses to commands or reactivity to stimuli between rations in any of the trials or with respect to which trainer had trained the horse. There were, however, differences (P<0.05) among horses, handlers and judges with respect to the scores. It appears that addition of a moderate amount of starchy feed to a horse's ration has less influence on the horse's trainability and reactivity than the animal's natural temperament and handler ability. KW -

Abstract: The relationship between facial hair whorl position and reactivity, as assessed by behavioural measures (handling score = HS; startle reaction to a suddenly appearing novel object = SR; latency to touch a novel object = LNO) and heart rate measures (mean HR; increase in heart rate = IHR) were studied using 55 Konik horses reared either under conventional stable conditions or in the forest reserve. Horses were classified into four groups according to the whorl position and/or shape: (1) high, single whorl above the top eye line, n = 9; (2) medium, single whorl between the top and the bottom eye line, n = 30; (3) low, single whorl below the bottom eye line, n = 10; and (4) elongated or double whorl, n = 6. Horses with a high whorl position demonstrated a lesser degree of manageability as expressed by a lower HS compared to individuals with medium (P = 0.002) or low whorl positions (P = 0.016). Horses with different whorl positions did not differ significantly in their startle response to a suddenly appearing novel object (P = 0.685). The horses with an elongated or double whorl, which appeared only in the forest group, took significantly longer to approach the novel object than horses with medium (P = 0.006) or low (P = 0.005) whorl positions. No significant differences in mean HR and IHR between groups (HR: P = 0.629 and IHR: P = 0.214) were found. In conclusion, this study supports the relationship between the position of the hair whorl on the horses' head and their manageability during handling, as well as the latency to approach an unknown object.