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Fureix, C., Bourjade, M., Henry, S., Sankey, C., & Hausberger, M. (2012). Exploring aggression regulation in managed groups of horses Equus caballus. Appl. Anim. Behav. Sci., 138(3–4), 216–228.
Abstract: Horses are highly social animals that have evolved to live in social groups. However, in modern husbandry systems, single housing prevails where horses experience social isolation, a challenge-to-welfare factor. One major reason for this single housing is the owners’ concerns that horses may injure each other during aggressive encounters. However, in natural conditions, serious injuries due to aggressive encounters are rare. What could therefore explain the claimed risks of group living for domestic horses? Basing our questioning on the current knowledge of the social life of horses in natural conditions, we review different practices that may lead to higher levels of aggression in horses and propose practical solutions. Observations of natural and feral horses mostly indicate a predominance of low frequencies and mild forms of aggression, based on subtle communication signals and ritualized displays and made possible by group stability (i.e. stable composition), dominance hierarchy and learning of appropriate social skills by young horses. Obviously, adults play a major role here in canalizing undesirable behaviours, and social experience during development, associated with a diversity of social partners, seems to be a prerequisite for the young horse to become socially skilled. Given the natural propensity of horses to have a regulation of aggression in groups, the tendency to display more aggression in groups of domestic horses under some management practices seems clearly related to the conditions offered. We therefore review the managing practices that could trigger aggressiveness in horses. Non social practices (space, resource availability) and social practices (group size, stability of membership, composition and opportunities for social experiences during development) in groups of domestic horses are discussed here. Finally, we propose simple practical solutions leading to more peaceful interactions in groups of domestic horses, based on the knowledge of horses’ natural social life which therefore should be enhanced (e.g. ensuring roughage availability, favouring group stability, introducing socially experienced adults in groups of young horses, etc.). The state of the art indicates that many questions still need to be answered. Given the importance of the associated welfare issues and the consequences on the use of horses, further research is required, which could benefit horses… and humans.
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Davies Morel, M. C. G., Newcombe, J. R., & Holland, S. J. (2002). Factors affecting gestation length in the Thoroughbred mare. Animal Reproduction Science, 74(3-4), 175–185.
Abstract: In order to assist in the accurate prediction of the timing of parturition in the mare true gestation length, along with the potential effect of a number of factors, was investigated. Data from 433 Thoroughbred foal pregnancies were used. Sequential ultrasonic scanning allowed the true gestation length (fertilisation-parturition) to be ascertained, as apposed to previous work, which used the mating-parturition interval. An average gestation length of 344.1+/-0.49 days was evident. Colt foal pregnancies were significantly (P<0.001) longer (346.2+/-0.72) than fillies (342.4+/-0.65). Month of birth had a significant effect on gestation length in all foals (P<0.001). With foals born in January having the shortest gestation lengths and those born in April the longest. Mare age, year of birth, stallion age, stud farm and the interval between ovulation and mating had no significant effect. It is concluded that (i) the gestation length range (315-388 days), all resulting in viable foals is noteworthy and of clinical importance when considering the classification of dysmaturity in foals, (ii) mares carrying colt foals due to be born in the middle of the breeding season (April) are likely to have the longer gestation lengths.
Keywords: Gestation length; Mare age; Foals; Month of year; Ovulation-mating interval
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Mills, D. S., Alston, R. D., Rogers, V., & Longford, N. T. (2002). Factors associated with the prevalence of stereotypic behaviour amongst Thoroughbred horses passing through auctioneer sales. Appl. Anim. Behav. Sci., 78(2-4), 115–124.
Abstract: The objective of this study was to evaluate whether sex, age and/or coat colour were associated with the occurrence of stereotypic behaviour in the horse and to assess whether the occurrence of one type of stereotypy in an individual was associated with the occurrence of another specific type of stereotypy. The incidence of stereotypic boxwalking, weaving (both locomotor stereotypies) and oral stereotypy in 4061 Thoroughbred horses passing through five bloodstock auctions were recorded from sale declarations and information on returns. An overall prevalence of 5.1% was recorded, and varied with sex (P<0.001) and age (P<0.001) but not coat colour (P=0.495). Prevalence was higher in females, geldings, and 2-year-olds. Examination of the assumption that stereotypies are acquired independently suggested a higher than expected prevalence of animals with more than one stereotypy. The interaction was not the same for all forms of stereotypy recorded. The effect was greatest between boxwalking and weaving, (odds ratio 13.6) whilst combinations involving oral and locomotor stereotypies had lower odds ratios (between 2.9 and 4.9).
Keywords: Behaviour; Horses; Management; Prevalence; Stereotypy; Stress
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Waters, A. J., Nicol, C. J., & French, N. P. (2002). Factors influencing the development of stereotypic and redirected behaviours in young horses: findings of a four year prospective epidemiological study. Equine Vet J, 34(6), 572–579.
Abstract: Stereotypies are invariant and repetitive behaviour patterns that seemingly have no function, which tend to develop in captive animals faced with insoluble problems and may be indicative of reduced welfare. A 4 year prospective study of the factors influencing the development of stereotypic and redirected behaviours (abnormal behaviour) in a population of 225 young Thoroughbred and part-Thoroughbred horses was conducted between 1995 and 1999. Abnormal behaviour affected 34.7% of the population. Multivariable analysis showed that foals of low- or middle-ranking mares were less likely to develop abnormal behaviour than foals of dominant mares (rate ratio (RR) 0.23, P<0.01; RR 0.48, P<0.01, respectively). Weaning by confinement in a stable or barn was associated with an increased rate of development of abnormal behaviour, compared with paddock-weaning (RR 2.19, P<0.05), and housing in barns, rather than at grass after weaning, was associated with a further increase (RR 2.54, P<0.01). Specific stereotypic and redirected behaviours were then considered as separate outcomes. Crib-biting was initiated by 10.5% of horses at median age 20 weeks, weaving by 4.6% of horses at median age 60 weeks, box-walking by 2.3% of horses at median age 64 weeks and wood-chewing by 30.3% of horses at median age 30 weeks. Wood-chewing developed at a lower rate in horses born to subordinate or mid-ranking mares than in horses born to dominant mares (RR 0.29, P<0.01; RR 0.41, P<0.01, respectively), and at a higher rate in horses kept in barns or stables rather than at grass after weaning (RR 4.49, P<0.001; RR 1A6, P<0.001, respectively). Feeding concentrates after weaning was associated with a 4-fold increase in the rate of development of crib-biting (RR 4.12, P = 0.02). The results of this study support the idea that simple changes in feeding, housing and weaning practices could substantially lower the incidence of abnormal behaviour in young horses.
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Cameron, E. Z. (2004). Facultative adjustment of mammalian sex ratios in support of the Trivers-Willard hypothesis: evidence for a mechanism. Proc Biol Sci, 271(1549), 1723–1728.
Abstract: Evolutionary theory predicts that mothers of different condition should adjust the birth sex ratio of their offspring in relation to future reproductive benefits. Published studies addressing variation in mammalian sex ratios have produced surprisingly contradictory results. Explaining the source of such variation has been a challenge for sex-ratio theory, not least because no mechanism for sex-ratio adjustment is known. I conducted a meta-analysis of previous mammalian sex-ratio studies to determine if there are any overall patterns in sex-ratio variation. The contradictory nature of previous results was confirmed. However, studies that investigated indices of condition around conception show almost unanimous support for the prediction that mothers in good condition bias their litters towards sons. Recent research on the role of glucose in reproductive functioning have shown that excess glucose favours the development of male blastocysts, providing a potential mechanism for sex-ratio variation in relation to maternal condition around conception. Furthermore, many of the conflicting results from studies on sex-ratio adjustment would be explained if glucose levels in utero during early cell division contributed to the determination of offspring sex ratios.
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Zaine, L., Ferreira, C., de O. S. Gomes, M., Monti, M., Tortola, L., Vasconcellos, R. S., et al. (2011). Faecal IgA concentration is influenced by age in dogs. British Journal of Nutrition, 106(Supplement S1), S183–S186.
Abstract: Data comparing age-related alterations in faecal IgA concentrations of dogs are not available in the literature. The present study aimed to
compare the faecal concentrations of IgA in puppies, mature and senior dogs. A total of twenty-four beagle dogs were used, including eight puppies (5 months old, four females and four males), eight mature (4·6 years old, eight males) and eight senior dogs (10·6 years old, three males and five females). Fresh faecal samples were collected from each dog for three consecutive days and pooled by animal. After saline extraction, IgA content was measured by ELISA. Data were analysed by one-way ANOVA, and means were compared with Tukey’s test (P,0·05). Results showed that puppies have lower faecal IgA concentrations than mature dogs (P,0·05); senior animals presented intermediary results. The reduced faecal IgA concentration in puppies is consistent with the reduced serum and salivary IgA concentrations reported previously, suggesting a reduced mucosal immunity in this age group. Although some studies have found an increased serum IgA concentration in older dogs, this may differ from the intestinal secretion of IgA, which appears to be lower in some senior animals (four of the eight dogs studied). |
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Manning, G. S., & Ratanarat, C. (1970). Fasciolopsis buski (Lankester, 1857) in Thailand. Am J Trop Med Hyg, 19(4), 613–619.
Keywords: Adolescent; Adult; Aged; Animals; Buffaloes; Cattle; Child; Child, Preschool; *Disease Reservoirs; Dogs; Ecology; *Fasciolidae; Feces; Female; Health Surveys; Horses; Humans; Infant; Infant, Newborn; Male; Middle Aged; *Plants, Edible; Sex Factors; *Snails; Swine; Thailand; Trematode Infections/*epidemiology
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Nogueira, S. S. da C., Nogueira-Filho, S. L. G., Bassford, M., Silvius, K., & Fragoso, J. M. V. (2007). Feral pigs in Hawai`i: Using behavior and ecology to refine control techniques. Appl. Anim. Behav. Sci., 108(1-2), 1–11.
Abstract: Early Polynesians settlers were the first to introduce pigs to the Hawaiian Islands. Later Captain Cook brought European pigs during his first voyage to Hawai`i. Many other importations have followed. Animals from these introductions became feral and dispersed throughout the islands. Free-ranging pigs are now considered pests with negative impacts on some native biota. Several methods to control the ecological damage attributed to pigs have been adopted, such as fencing, hunting, live trapping and poisoning. However, the absence of behavioral knowledge in current control programs has resulted in inefficient management of this species. Therefore, the feral pig problem continues, and what before was almost strictly an agricultural and conservation concern has now become an urban problem as well. The aim of this study is to describe the state of knowledge on feral pig behavior in the Hawaiian Islands, introducing potential management approaches derived from the principles of behavioral ecology. Considering behavioral aspects of feral pig ecology, such as cognition and communication could help improve capture techniques, keep feral pigs away from urban areas and begin to resolve human-wildlife conflicts.
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Krishnan, A., Gandour, J. T., Ananthakrishnan, S., Bidelman, G. M., & Smalt, C. J. (). Functional ear (a)symmetry in brainstem neural activity relevant to encoding of voice pitch: A precursor for hemispheric specialization? Brain and Language, In Press, Corrected Proof.
Abstract: Pitch processing is lateralized to the right hemisphere; linguistic pitch is further mediated by left cortical areas. This experiment investigates whether ear asymmetries vary in brainstem representation of pitch depending on linguistic status. Brainstem frequency-following responses (FFRs) were elicited by monaural stimulation of the left and right ear of 15 native speakers of Mandarin Chinese using two synthetic speech stimuli that differ in linguistic status of tone. One represented a native lexical tone (Tone 2: T2); the other, T2', a nonnative variant in which the pitch contour was a mirror image of T2 with the same starting and ending frequencies. Two 40-ms portions of f0 contours were selected in order to compare two regions (R1, early; R2 late) differing in pitch acceleration rate and perceptual saliency. In R2, linguistic status effects revealed that T2 exhibited a larger degree of FFR rightward ear asymmetry as reflected in f0 amplitude relative to T2'. Relative to midline (ear asymmetry = 0), the only ear asymmetry reaching significance was that favoring left ear stimulation elicited by T2'. By left- and right-ear stimulation separately, FFRs elicited by T2 were larger than T2' in the right ear only. Within T2', FFRs elicited by the earlier region were larger than the later in both ears. Within T2, no significant differences in FFRS were observed between regions in either ear. Collectively, these findings support the idea that origins of cortical processing preferences for perceptually-salient portions of pitch are rooted in early, preattentive stages of processing in the brainstem.
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Adelman, M., & Knijnik, J. (2013). Gender and Equestrian Sport. Dordrecht: Springer.
Abstract: This volume brings together studies from various disciplines of the social sciences and humanities (Anthropology, Sociology, Cultural Studies, History and Literary theory) that examine the equestrian world as a historically gendered and highly dynamic field of contemporary sport and culture. From elite international dressage and jumping, polo and the turf, to the rodeo world of the Americas and popular forms of equestrian sport and culture, we are introduced to a range of issues as they unfold at local and global, national and international levels. Students and scholars of gender, culture and sport will find much of interest in this original look at contemporary issues such as “engendered” (women’s and men’s) dentities/subjectivities of equestrians, representations of girls, horses and the world of adventure in juvenile fiction; the current “feminization” of particular equestrian activities (and where boys and men stand in relation to this); how broad forms of social inequality and stratification play themselves out within gendered equestrian contexts; men and women and their relation to horses within the framework of current discussions on the relation of animals to humans (which may include not only love and care, but also exploitation and violence), among others. Singular contributions that incorporate a wide variety of classic and contemporary theoretical perspectives and empirical methodologies show how horse cultures around the globe contribute to historical and current constructions of embodied “femininities” and “masculinities”, reflecting a world that has been moving “beyond the binaries” while continuing to be enmeshed in their persistent and contradictory legacy. The final chapter makes a brave attempt at synthesizing individual chapters and moving forward from the evidences they provide, to suggest a compelling agenda for future research.
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