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Barber, J. A., & Crowell-Davis, S. L. (1994). Maternal behavior of Belgian (Equus caballus) mares. Appl. Anim. Behav. Sci., 41(3-4), 161–189.
Abstract: The relationship between ten Belgian mares and their offspring was studied from the first day of foal life to 17 weeks of age. Mares and foals spent more time at greater distances from each other as foals matured. Mares exhibited the recumbency response, being in closer proximity to their foals when foals were recumbent than when they were upright. Foals initiated the majority of nursing bouts. Frequency and duration of nursing bouts and percentage of time resting recumbently declined as foals matured. Foals also terminated the their foals, and they were most likely to do so in the first month of foal life. Maternal initiation of nursing. There was usually no discernible foal response to maternal aggression. Little difference between maternal behavior directed towards colts and fillies was found for all aspects of the study. Maternal behavior in the Belgian draft horse was similar to that reported for other equid breeds.
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Wallin, L., Strandberg, E., & Philipsson, J. (2001). Phenotypic relationship between test results of Swedish Warmblood horses as 4-year-olds and longevity. Livestock Production Science, 68(2-3), 97–105.
Abstract: The relationship between longevity and different traits scored in the Swedish Riding Horse Quality Test (RHQT) was studied to evaluate their use as predictors of survival. Data comprised 1815 Warmblood horses born between 1969 and 1982 that had participated in the RHQT as 4-year-olds. Survival information was obtained via a questionnaire sent to owners of horses that had participated in the RHQT between 1973 and 1986. All phenotypic values of traits scored at 4 years of age were adjusted for the effect of place/year (event). Survival analysis was performed taking into account censoring. Traits having significant effects on longevity were: conformation, legs (included in conformation), orthopaedic status, jumping ability, and the horses' combined classification score for dressage and jumping talents, respectively. Orthopaedic health had the greatest influence on longevity, and demonstrated the importance of judging health traits in young sports horses. The results of this study confirmed that there is a significant phenotypic relationship between many of the RHQT traits and longevity, and thus the possibility of using them as predictors of survival.
Keywords: Horse; Longevity; Survival analysis; Test traits
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Gorecka, A., Golonka, M., Chruszczewski, M., & Jezierski, T. (2007). A note on behaviour and heart rate in horses differing in facial hair whorl. Appl. Anim. Behav. Sci., 105(1-3), 244–248.
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.
Keywords: Horse; Hair whorls; Behavioural tests; Reactivity; Heart rate
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Chiba, K., Ikai, A., Kawamura-Konishi, Y., & Kihara, H. (1994). Kinetic study on myoglobin refolding monitored by five optical probe stopped-flow methods. Proteins, 19(2), 110–119.
Abstract: The refolding kinetics of horse cyanometmyoglobin induced by concentration jump of urea was investigated by five optical probe stopped-flow methods: absorption at 422 nm, tryptophyl fluorescence at around 340 nm, circular dichroism (CD) at 222 nm, CD at 260 nm, and CD at 422 nm. In the refolding process, we detected three phases with rate constants of > 1 x 10(2) s-1, (4.5-9.3) s-1, and (2-5) x 10(-3) s-1. In the fastest phase, a substantial amount of secondary structure (approximately 40%) is formed within the dead time of the CD stopped-flow apparatus (10.7 ms). The kinetic intermediate populated in the fastest phase is shown to capture a hemindicyanide, suggesting that a “heme pocket precursor” recognized by hemindicyanide must be constructed within the dead time. In the middle phase, most of secondary and tertiary structures, especially around the captured hemindicyanide, have been constructed. In the slowest phase, we detected a minor structural rearrangement accompanying the ligand-exchange reaction in the fifth coordination of ferric iron. We present a possible model for the refolding process of myoglobin in the presence of the heme group.
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Jansen, W. L., van Alphen, M., Berghout, M., Everts, H., & Beynen, A. C. (2001). An approach to assessment of the efficiency of dietary energy utilization by horses and ponies kept at riding schools. Vet Q, 23(4), 195–198.
Abstract: The ratio of calculated net energy intake (NEi) to calculate net energy requirement (NEr) might serve as an indicator of the efficiency of dietary energy utilization. The ratio was determined for 93 horses and ponies from 10 riding schools. For each animal with an assumed constant body weight, energy intake and energy requirements were assessed. On average, the estimated NEi was 14% greater than NEr. There was a significant, negative association between crude fibre intake and the NEi: NEr ratio. Earlier work indicated that extra fat intake may lead to over estimation of the calculated energy value of the ration due to changes in macronutrient digestibility. Dietary fat concentration was found to range from 32 to 52 g/kg dry matter (5 to 6 g/MJ net energy), but on the basis of digestibility trials this range in fat concentration is too small to significantly influence the NEi: NEr ratio. This study shows that assessment of the efficiency of dietary energy utilization under normal conditions, on the basis of the NEi: NEr ratio is fraught with uncertainty.
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Ballew, R. M., Sabelko, J., & Gruebele, M. (1996). Direct observation of fast protein folding: the initial collapse of apomyoglobin. Proc. Natl. Acad. Sci. U.S.A., 93(12), 5759–5764.
Abstract: The rapid refolding dynamics of apomyoglobin are followed by a new temperature-jump fluorescence technique on a 15-ns to 0.5-ms time scale in vitro. The apparatus measures the protein-folding history in a single sweep in standard aqueous buffers. The earliest steps during folding to a compact state are observed and are complete in under 20 micros. Experiments on mutants and consideration of steady-state CD and fluorescence spectra indicate that the observed microsecond phase monitors assembly of an A x (H x G) helix subunit. Measurements at different viscosities indicate diffusive behavior even at low viscosities, in agreement with motions of a solvent-exposed protein during the initial collapse.
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Hausberger, M., Gautier, E., Muller, C., & Jego, P. (2007). Lower learning abilities in stereotypic horses. Appl. Anim. Behav. Sci., 107(3-4), 299–306.
Abstract: The question of whether motor stereotypies may be associated with learning disorders is a highly debated issue both in humans and animals, but evidence is still scarce. The aim of the present study was to investigate the relation between the occurrence of stereotypic behaviours in horses where stereotypies are well described and learning abilities measurable. Seventy horses were observed in their box at two periods (August and November) and were then submitted to an instrumental task (opening a chest by raising the lid using the nose). Fifty-one of them had shown stereotypic behaviours at both periods. It appeared that more stereotypic horses (36/51) were unsuccessful than non-stereotypic horses (3/19) in the learning task. When successful, they required a longer time in order to perform the task (368 s on average against 220 for the non-stereotypic horses). No difference was found according to the type of stereotypy performed. This is to our knowledge the first time that a relation is found between stereotypy and learning in an animal species. The additional finding that stereotypic horses spent less time lying down and sleeping suggests a possible role of attentional processes. This finding has important implications for the horse industry.
Keywords: Stereotypies; Learning ability; Horses
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Ionita, J. C., Poncet, P. A., Doherr, M. G., & Steiger, A. (2006). [Evaluation of the quality of husbandry of Franches-Montagnes horses in their breeding farms]. Schweiz Arch Tierheilkd, 148(4), 191–197.
Abstract: The quality of husbandry of Franches-Montagnes horses (FM) in Switzerland is evaluated on the basis of an investigation carried out in 2002 by the Swiss FM breeding federation. Questionnaires were sent to 3500 of its members and the results include data from 968 breeding enterprises, housing a total of 3965 FM: 46.1% were breeding mares (61.0% with foal at foot), 26.5% young stock, 1.3% stallions and 26.0% non breeding stock (74.6% of which were pleasure horses and 25.4% working horses). 57.6% of the FM were housed in individual boxes with or without permanent outdoor access, 25.4% were hold in groups with or without permanent outdoor access, the remaining 17.0% were kept in standing stalls. 95.0% of the FM had at least visual contact with other equines and 99.2% had sufficient light in their stable. 88.1% were stabled on long stalk straw, while only 4.3% were bedded on other materials other than straw. The average time spent at pasture per horse and per week ranged from 96.5 +/- 51.6 hours in summer to 27.2 +/- 26.7 hours in winter. On average, a FM is used for 8.3 +/- 6.5 hours per week. Horses with an paddock at their disposal spend an average of 39.8 +/- 45.9 hours there per week.
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Lansade, L., Bouissou, M. - F., & Erhard, H. W. (2008). Fearfulness in horses: A temperament trait stable across time and situations. Appl. Anim. Behav. Sci., 115(3-4), 182–200.
Abstract: The purpose of this study was to test the existence of a “fearfulness” trait in horses, by testing the stability across situations and over time of the responses to different fear-eliciting situations. It was also to identify which behavioural parameters are the best indicators of this trait. Sixty-six Welsh ponies and 44 Anglo-Arab horses were successively tested at 8 months and 1.5 years of age. Of these, 33 Welsh ponies and 21 Anglo-Arabs were also tested at 2.5 years of age. At each age, they were subjected to four test situations. The first test involved the introduction of a novel object in the test pen (novel object test). In the second test, a novel area was placed in the pen between the horse and a bucket of food, to determine the time the horse took to cross the area (novel area test). Finally, the third test consisted in suddenly opening an umbrella in front of the horse while it was eating (surprise test). During these tests, many behavioural parameters were recorded. A fourth test consisted of a surprise test during which the horse was held by a handler while its heart rate was measured. Spearman correlations were used to identify links between behavioural parameters measured during different tests and between different ages. Reactions to the first three tests showed consistency between them and over time. Among all the behavioural parameters measured during these tests, some presented high stability over time and were well correlated with behaviours expressed during other tests, indicating they are the best indicators of a fearfulness trait: the frequency of licking/nibbling the novel object, the time to put one foot on the novel area and to eat from a bucket placed just behind it, and the flight distance and the time to eat under the opened umbrella. The stability across responses expressed in various fear-eliciting events and over time from 8 months to 2.5 years of age suggests the existence of a [`]fearfulness' trait in horses. The different indexes of heart rate measured or calculated during the surprise effect present limited stability over time and almost no correlation with the behavioural parameters measured during the other three tests. We conclude that, in contrast to the previously mentioned behaviours, these are not reliable measures of a temperament trait. From a practical point of view, this study shows that it is possible to identify a horse's level of fearfulness as early as 8 months of age using the first three tests.
Keywords: Horse; Temperament; Fearfulness; Novelty; Suddenness; Behavioural tests
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Robert, C., Valette, J. P., & Denoix, J. M. (2001). The effects of treadmill inclination and speed on the activity of three trunk muscles in the trotting horse. Equine Vet J, 33(5), 466–472.
Abstract: The purpose of this study was to evaluate the effects of speed and slope on the activity of trunk muscles. The electromyographic (EMG) activity of the splenius (Sp), longissimus dorsi (LD) and rectus abdominis (RA) muscles was recorded with surface electrodes during treadmill locomotion at trot for different combinations of speed (3.5 to 6 m/s) and slope (0 to 6%). Raw EMG signals were processed to determine activity duration, onset and end and integrated EMG (IEMG). For the 3 muscles investigated, onset and end of activity were obtained earlier in the stride cycle when speed increased. A longer duration of activity for the LD, a shorter duration for the RA and an unchanged duration for the Sp were also observed. The IEMG of the latter was poorly affected by speed, whereas it increased linearly with speed for the 2 other muscles. When treadmill inclination changed from 0 to 6%, EMG activity of the LD and RA began and ended later; a longer activity duration was noted. Temporal parameters for Sp did not change with slope. A significant and progressive increase in the IEMG of the 3 muscles was observed with increasing slope. This evaluation of the activity of trunk muscles provides objective data for the use of speed or slope in training programmes.
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