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de Waal, F. B., & Luttrell, L. M. (1986). The similarity principle underlying social bonding among female rhesus monkeys. Folia Primatol (Basel), 46(4), 215–234.
Abstract: Twenty adult female rhesus monkeys (Macaca mulatta) were observed over a three-year period. They lived in a mixed captive group with kinship relations known for three generations. The study's aim was to test Seyfarth's [J. theor. Biol. 65: 671-698, 1977] model of rank-related grooming and to investigate two other possible determinants of social bonding, i.e. relative age and the group's stratification into two social classes. Data on affiliation, coalitions, and social competition were collected by means of both focal observation and instantaneous time sampling. Whereas certain elements of the existing model were confirmed, its explanatory principles were not. Social competition did not result in more contact among close-ranking females (the opposite effect was found), and the relation between affiliative behavior and coalitions was more complex than predicted. Based on multivariate analyses and a comparison of theoretical models, we propose a simpler, more encompassing principle underlying interfemale attraction. According to this 'similarity principle', rhesus females establish bonds with females whom they most resemble. The similarity may concern genetical and social background, age, hierarchical position and social class. Effects of these four factors were independently demonstrated. The most successful model assumed that similarity factors influence female bonding in a cumulative fashion.
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Whiten, A. (2005). The second inheritance system of chimpanzees and humans. Nature, 437(7055), 52–55.
Abstract: Half a century of dedicated field research has brought us from ignorance of our closest relatives to the discovery that chimpanzee communities resemble human cultures in possessing suites of local traditions that uniquely identify them. The collaborative effort required to establish this picture parallels the one set up to sequence the chimpanzee genome, and has revealed a complex social inheritance system that complements the genetic picture we are now developing.
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Ruggieri, V. (1999). The running horse stops: the hypothetical role of the eyes in imagery of movement. Percept Mot Skills, 89(3 Pt 2), 1088–1092.
Abstract: To examine the hypothetical role of the eyes in visual mental imagery of movement 72 undergraduate women students in psychology were asked to imagine a running horse and then to produce the same mental image without moving the eyes and the head. In 59% of the subjects interesting modifications of the imagined movement appeared: 37% observed an inhibition of the movement and 19% an evident slowing up of the moving figure. The interpretation of this result was made by hypothesizing that the eyes are concretely involved in visual imagery processes.
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Milouchine, V. N. (1980). The role of WHO in international studies on the ecology of influenza in animals. Comp Immunol Microbiol Infect Dis, 3(1-2), 25–31.
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Stahlbaum, C. C., & Houpt, K. A. (1989). The role of the Flehmen response in the behavioral repertoire of the stallion. Physiol. Behav., 45(6), 1207–1214.
Abstract: The role of the Flehmen response in equine behavior was investigated under field and laboratory conditions. In Experiment 1, a field study made of five stallions on pasture with between three and eighteen mares each during the season indicated the following: 1) The Flehmen response was most frequently preceded by nasal, rather than oral, investigation of substances; 2) The stallions' rate of Flehmen varied with the estrous cycles of the mares; 3) The rate of Flehmen response did not show a variation with time of day; and 4) The Flehmen response was most frequently followed by marking behaviors rather than courtship behaviors. The results suggest that the Flehmen response is not an immediate component of sexual behavior, e.g., courtship of the stallion but may be involved in the overall monitoring of the mare's estrous cycle. Therefore the Flehmen response may contribute to the chemosensory priming of the stallion for reproduction. In Experiment 2 stallions were presented with urine or feces of mares in various stages of the reproductive cycle as well as with their own or other males' urine or feces. The occurrence of sniffing and Flehmen was used to determine the discriminatory ability of the stallions. Stallions can differentiate the sex of a horse on the basis of its feces alone, but cannot differentiate on the basis of urine. This ability may explain the function of fecal marking behavior of stallions.
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Hill, S. E., & Ryan, M. J. (2006). The role of model female quality in the mate choice copying behaviour of sailfin mollies. Biol Lett, 2(2), 203–205.
Abstract: Female mate choice copying is a socially mediated mate choice behaviour, in which a male's attractiveness to females increases if he was previously chosen by another female as a mate. Although copying has been demonstrated in numerous species, little is known about the specific benefits it confers to copying females. Here we demonstrate that the mate choice behaviour of female sailfin mollies (Poecilia latipinna) is influenced by the phenotypic quality of model females with whom males are observed consorting. Test females choosing between two males of similar body length were found to significantly increase time spent with previously non-preferred males after having observed them with a relatively high-quality female. Conversely, females were found to significantly decrease time spent with previously preferred males after having observed them with a relatively low-quality female. Female mate choice copying might be maintained by selection based on the heuristic value it provides females choosing between males whose quality differences are not easily distinguishable.
Keywords: Animals; *Choice Behavior; Female; Male; *Mating Preference, Animal; Poecilia/*physiology
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Anderson, T. M., McIlwraith, C. W., & Douay, P. (2004). The role of conformation in musculoskeletal problems in the racing Thoroughbred. Equine Vet J, 36(7), 571–575.
Abstract: REASONS FOR PERFORMING STUDY: The relationship of conformation to future potential injury is a standard approach in practise but, at present, is largely based on subjective observations. OBJECTIVE: To measure conformation in 3-year-old Thoroughbreds and objectively test its relationship with the occurrence of musculoskeletal problems. METHODS: Conformation measurements were taken from photographs using specific reference points marked on the horses and processed on the computer. Clinical observations were recorded for each horse on a regular basis. Stepwise (forward) logistic regression analysis was performed to investigate the relationship between the binary response of the clinical outcomes probability and the conformation variables by the method of maximum likelihood. RESULTS: Clinical outcomes significantly (P<0.05) associated with conformational variables included effusion of the front fetlock, effusion of the right carpus, effusion of the carpus, effusion of the hind fetlock, fracture of the left or right carpus, right front fetlock problem and hind fetlock problem. CONCLUSIONS: Offset knees (offset ratio) contributed to fetlock problems. Long pasterns increased the odds of a fracture in the front limb. An increase in the carpal angle as viewed from the front (carpal valgus) may serve as a protective mechanism, as the odds for a carpal fracture and carpal effusion decreased with an increase in the carpal angle. POTENTIAL RELEVANCE: This study demonstrates relationships between conformation and musculoskeletal disease in the racehorse. The information may be useful in selection and management of the racing Thoroughbred.
Keywords: Animals; Carpus, Animal/anatomy & histology/physiology; Horse Diseases/etiology/*pathology/surgery; Horses/*anatomy & histology/injuries/physiology; Likelihood Functions; Logistic Models; Muscle, Skeletal/*anatomy & histology/pathology; Musculoskeletal Diseases/pathology/surgery/*veterinary; Tarsus, Animal/anatomy & histology/physiology; Treatment Outcome
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Bell, R. J. W., Kingston, J. K., Mogg, T. D., & Perkins, N. R. (2007). The prevalence of gastric ulceration in racehorses in New Zealand. N Z Vet J, 55(1), 13–18.
Abstract: AIM: To establish the prevalence and factors influencing the prevalence and severity of gastric ulceration in racehorses in New Zealand. METHODS: Horses (n=171) in active training for racing by trainers (n=24) located throughout New Zealand were examined using gastroscopy during 2003 and 2004. Images of the examination were recorded and reviewed, and an ordinal grade based on the severity of gastric ulceration present was assigned, using the grading system proposed by the Equine Gastric Ulcer Council (EGUC). Information about the horses such as age, breed, sex, stabling, time at pasture, pasture quality, and presence of clinical signs consistent with equine gastric ulcer syndrome (EGUS) was recorded. RESULTS: Of the 171 horses in the study, 133 (78%) were Thoroughbreds and 38 (22%) were Standardbreds. Evidence of gastric ulceration was present in 151 (88.3%) of these. Prevalence of ulceration was higher at the lesser curvature (LC) and greater curvature (GC) of the stomach than at the saccus caecus (SC; p<0.01), and ulceration was more severe at the LC than at either the GC (p=0.02) or the SC (p<0.001). The prevalence of ulceration did not differ between the two breeds (p=0.51) or between horses of differing ages (p=0.56). Gastric ulceration was evident in 125/141 (89%) horses kept at pasture for at least 4 h/day, in all 13 (100%) horses kept at pasture full time, and in 16/17 (94%) horses stabled full time. Prevalence and severity of ulceration did not differ between horses stabled full time, kept at pasture for part of the day or kept at pasture full time (p=0.33 and 0.13, respectively), and for horses grazed on pasture severity of ulceration did not vary significantly with the quality of the pasture (p=0.12). Neither prevalence (p=0.26) nor severity (p=0.49) of gastric ulceration varied significantly with duration of training. CONCLUSIONS: The prevalence of gastric ulceration in racehorses in New Zealand is similar to that reported elsewhere for horses in active training for racing. Access to pasture for some or all of the day did not appear to be protective.
Keywords: Age Factors; *Animal Feed; Animal Husbandry/methods; Animals; Female; Horse Diseases/*epidemiology/pathology/prevention & control; Horses; Male; New Zealand/epidemiology; Physical Conditioning, Animal/*adverse effects/physiology; Poaceae; Prevalence; Risk Factors; Severity of Illness Index; Sex Factors; Stomach Ulcer/epidemiology/pathology/prevention & control/*veterinary; Time Factors
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Alexander, F. (1951). The preparation of Biebl loops and Thiry-Vella fistulae of the ileum of the horse. J Physiol, 115(4), 63–4 P.
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Wasserman, E. A., Gagliardi, J. L., Cook, B. R., Kirkpatrick-Steger, K., Astley, S. L., & Biederman, I. (1996). The pigeon's recognition of drawings of depth-rotated stimuli. J Exp Psychol Anim Behav Process, 22(2), 205–221.
Abstract: Four experiments used a four-choice discrimination learning paradigm to explore the pigeon's recognition of line drawings of four objects (an airplane, a chair, a desk lamp, and a flashlight) that were rotated in depth. The pigeons reliably generalized discriminative responding to pictorial stimuli over all untrained depth rotations, despite the bird's having been trained at only a single depth orientation. These generalization gradients closely resembled those found in prior research that used other stimulus dimensions. Increasing the number of different vantage points in the training set from one to three broadened the range of generalized testing performance, with wider spacing of the training orientations more effectively broadening generalized responding. Template and geon theories of visual recognition are applied to these empirical results.
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