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da Cruz, A. B., Hirata, S., dos Santos, M. E., & Mendonça, R. S. (2023). Show me your best side: Lateralization of social and resting behaviors in feral horses. Behav. Process., 206, 104839.
Abstract: Growing evidence shows a variety of sensorial and motor asymmetries in social and non-social interactions in various species, indicating a lateralized processing of information by the brain. Using digital video cameras on tripods and drones, this study investigated lateralization in frequency and duration of social behavior patterns, in affiliative, agonistic, and resting contexts, in a feral population of horses (Equus ferus caballus) in Northern Portugal, consisting of 37 individuals organized in eight harem groups. Affiliative interactions (including grooming) were more often performed, and lasted longer, when recipients were positioned to the right side. In recumbent resting (animals lying down) episodes on the left side lasted longer. Our results of an affiliative behavior having a right side tendency, provide partial support to the valence-specific hypothesis of Ahern and Schwartz (1979) – left hemisphere dominance for positive affect, affiliative behaviors. Longer recumbent resting episodes on the left side may be due to synchronization. However, in both instances it is discussed how lateralization may be context dependent. Investigating the position asymmetries of social behaviors in feral equids will contribute to a better understanding of differential lateralization and hemispheric specialization from the ecological and evolutionary perspectives.
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Turpeinen, O. (1979). Effect of cholesterol-lowering diet on mortality from coronary heart disease and other causes. Circulation, 59(1), 1–7.
Abstract: International statistics indicate that there is a close correlation between the consumption of saturated fats (dairy fats and meat fats) and the mortality from coronary heart disease (CHD), and this conception has been confirmed by many epidemiological studies. Such studies alone, however, cannot prove the existence of a cause-and-effect relationship between these two variables; dietary intervention trials are needed. The Finnish Mental Hospital Study was such a trial, conducted in two hospitals near Helsinki in 1959--1971. Practically total replacement of dairy fats by vegetable oils in the diets of these hospitals was followed by a substantial reduction in the mortality of men from CHD. Total mortality also appeared to be reduced. As to the causes of death other than CHD, none was significantly influenced by dietary change. This was also true for malignant neoplasms. To alleviate the burden of CHD on public health, many investigators have recommended important changes in the quantity and quality of dietary fats.
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Carroll, G. L., Matthews, N. S., Hartsfield, S. M., Slater, M. R., Champney, T. H., & Erickson, S. W. (1997). The effect of detomidine and its antagonism with tolazoline on stress-related hormones, metabolites, physiologic responses, and behavior in awake ponies. Vet Surg, 26(1), 69–77.
Abstract: Six ponies were used to investigate the effect of tolazoline antagonism of detomidine on physiological responses, behavior, epinephrine, norepinephrine, cortisol, glucose, and free fatty acids in awake ponies. Each pony had a catheter inserted into a jugular vein 1 hour before beginning the study. Awake ponies were administered detomidine (0.04 mg/kg intravenously [i.v.]) followed 20 minutes later by either tolazoline (4.0 mg/kg i.v.) or saline. Blood samples were drawn from the catheter 5 minutes before detomidine administration (baseline), 5 minutes after detomidine administration, 20 minutes before detomidine administration which was immediately before the administration of tolazoline or saline (time [T] = 0), and at 5, 30, and 60 minutes after injections of tolazoline or saline (T = 5, 30, and 60 minutes, respectively). Compared with heart rate at T = 0, tolazoline antagonism increased heart rate 45% at 5 minutes. There was no difference in heart rate between treatments at 30 minutes. Blood pressure remained stable after tolazoline, while it decreased over time after saline. Compared with concentrations at T = 0, tolazoline antagonism of detomidine in awake ponies resulted in a 55% increase in cortisol at 30 minutes and a 52% increase in glucose at 5 minutes. The change in free fatty acids was different for tolazoline and saline over time. Free fatty acids decreased after detomidine administration. Free fatty acids did not change after saline administration. After tolazoline administration, free fatty acids increased transiently. Tolazoline tended to decrease sedation and analgesia at 15 and 60 minutes postantagonism. Antagonism of detomidine-induced physiological and behavioral effects with tolazoline in awake ponies that were not experiencing pain appears to precipitate a stress response as measured by cortisol, glucose, and free fatty acids. If antagonism of an alpha-agonist is contemplated, the potential effect on hormones and metabolites should be considered.
Keywords: Adrenergic alpha-Antagonists/administration & dosage/*pharmacology; Animals; Behavior, Animal/drug effects/physiology; Blood Glucose/metabolism; Blood Pressure/drug effects/physiology; Consciousness/physiology; Dose-Response Relationship, Drug; Drug Interactions; Epinephrine/blood; Fatty Acids, Nonesterified/blood; Female; Heart Rate/drug effects/physiology; Horse Diseases/metabolism/physiopathology/psychology; Horses/blood/metabolism/*physiology; Hydrocortisone/blood; Hypnotics and Sedatives/administration & dosage/*pharmacology; Imidazoles/administration & dosage/*pharmacology; Injections, Intravenous; Male; Norepinephrine/blood; Receptors, Adrenergic, alpha/drug effects/*physiology; Stress/metabolism/physiopathology/veterinary; Time Factors; Tolazoline/administration & dosage/*pharmacology
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Alexander, F., & Collett, R. A. (1974). Pethidine in the horse. Res Vet Sci, 17(1), 136–137.
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Preston, S. D., & de Waal, F. B. M. (2002). Empathy: Its ultimate and proximate bases. Behav Brain Sci, 25(1), 1–20; discussion 20–71.
Abstract: There is disagreement in the literature about the exact nature of the phenomenon of empathy. There are emotional, cognitive, and conditioning views, applying in varying degrees across species. An adequate description of the ultimate and proximate mechanism can integrate these views. Proximately, the perception of an object's state activates the subject's corresponding representations, which in turn activate somatic and autonomic responses. This mechanism supports basic behaviors (e.g., alarm, social facilitation, vicariousness of emotions, mother-infant responsiveness, and the modeling of competitors and predators) that are crucial for the reproductive success of animals living in groups. The Perception-Action Model (PAM), together with an understanding of how representations change with experience, can explain the major empirical effects in the literature (similarity, familiarity, past experience, explicit teaching, and salience). It can also predict a variety of empathy disorders. The interaction between the PAM and prefrontal functioning can also explain different levels of empathy across species and age groups. This view can advance our evolutionary understanding of empathy beyond inclusive fitness and reciprocal altruism and can explain different levels of empathy across individuals, species, stages of development, and situations.
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Henning, J. M., & Zentall, T. R. (1981). Imitation, social facilitation, and the effects of ACTH 4-10 on rats' bar-pressing behavior. Am J Psychol, 94(1), 125–134.
Abstract: The effects of ACTH 4-10 on rats' imitation learning was examined during the acquisition and extinction of a bar-press response for water reinforcement. Rats were exposed to either a bar-pressing conspecific (OB), an experimentally naive conspecific (ON), or an empty box (OE) during bar-press acquisition. In a factorial design, each rat was then exposed to one of the same three conditions during extinction. An 80 mcg dose of ACTH 4-10 was administered to half of the rats in each group prior to observation. Performance differences during acquisition were generally small, but significant performance differences during extinction were found. Social facilitation was indicated by the finding that rats extinguished in the presence of a conspecific exhibited significantly greater resistance to extinction than rats extinguished in the presence of an empty box. An imitation effect was also found. Rats that observed a bar-pressing conspecific during both acquisition and extinction (group OB-OB) showed significantly greater resistance top extinction than did groups OB-ON, CB-OE, or OE-OE. There were no significant effects of the hormone, however, relative to saline controls.
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Griffin, A. S. (2008). Social learning in Indian mynahs, Acridotheres tristis: the role of distress calls. Anim. Behav., 75(1), 79–89.
Abstract: Socially acquired predator avoidance is a phenomenon in which individuals acquire an avoidance response towards an initially neutral stimulus after they have experienced it together with the antipredator signals of social companions. Earlier research has established that alarm calls used for intraspecific communication are effective stimuli for triggering acquisition. However, animals produce a large range of other antipredator responses that might engage antipredator learning. Here, I examine the effects of conspecific distress calls, a signal that is produced by birds when restrained by a predator, and that appears to be directed towards predators, rather than conspecifics, on predator avoidance learning in Indian mynahs, Acridotheres tristis. Distress calls reflect high levels of alarm in the caller and should, therefore, mediate robust learning. Experiment 1 revealed that subjects performed higher rates of head movements in response to a previously unfamiliar avian mount after it had been presented simultaneously with playbacks of conspecific distress vocalizations. Experiment 2 revealed that increased rates of head saccades resembled the spontaneous response evoked by a novel stimulus more closely than it resembled the response evoked by a perched raptor, suggesting that distress calls inculcated a visual exploratory response, rather than an antipredator response. While it is usually thought that the level of acquisition in learners follows a simple relationship with the level of alarm shown by demonstrators, the present results suggest that this relationship may be more complex. Antipredator signals with different functions may have differential effects on learners.
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Koba, Y., & Tanida, H. (2001). How do miniature pigs discriminate between people?: Discrimination between people wearing coveralls of the same colour. Appl. Anim. Behav. Sci., 73(1), 45–58.
Abstract: Seven experiments were conducted on four miniature pigs to determine: (1) whether the pigs can discriminate between people wearing the same coloured clothing; (2) what cues they rely on if they could discriminate. For 2 weeks before the experiments began, the pigs were conditioned in a Y-maze to receive raisins from the rewarder wearing dark blue coveralls. They were then given the opportunity to choose the rewarder or non-rewarder in these experiments. Each session consisted of 20 trials. Successful discrimination was that the pig chose the rewarder at least 15 times in 20 trials (P<0.05: by χ2-test). In Experiment 1, both rewarder and non-rewarder wore dark blue coveralls. By 20 sessions, all pigs successfully identified the rewarder. In Experiment 2: (1) both wore coveralls of the same new colours or (2) one of them wore coveralls of new colours. They significantly preferred the rewarder even though the rewarder and/or non-rewarder wore coveralls of new colours. In Experiment 3, both wore dark blue coveralls but olfactory cues were obscured and auditory cues were not given. The pigs were able to identify the rewarder successfully irrespective of changing auditory and olfactory cues. In Experiment 4, both wore dark blue coveralls but covered part of their face and body in different ways. The correct response rate decreased when a part of the face and the whole body of the rewarder and non-rewarder were covered. In Experiment 5, both wore dark blue coveralls and changed their apparent body size by shifting sitting position. The correct response rate increased as the difference in body size between the experimenters increased. In Experiment 6, the distance between the experimenters and the pig was increased by 30 cm increments. The correct response rate of each pig decreased as the experimenters receded from the pig, but performance varied among the pigs. In Experiment 7, the light intensity of the experimental room was reduced from 550 to 80 lx and then to 20 lx. The correct response rate of each pig decreased with the reduction in light intensity, but all the pigs discriminated the rewarder from the non-rewarder significantly even at 20 lx. In conclusion, the pigs were able to discriminate between people wearing coveralls of the same colour after sufficient reinforcement. These results indicate that pigs are capable of using visual cues to discriminate between people.
Keywords: Pigs; Learning; Recognition; Human-animal relationships
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Zehnder, A. M., Ramer, J. C., & Proudfoot, J. S. (2006). The use of altrenogest to control aggression in a male Grant's Zebra (Equus burchelli boehmi). J Zoo Wildl Med, 37(1), 61–63.
Abstract: A male Grant's Zebra (Equus burchelli boehmi) housed with two mares at the Indianapolis Zoo had a 9-yr history of intermittent aggressive behavior toward mares and other animals. Periods of separation allowed the mares time to heal after sustaining superficial bite wounds. On 26 March 2003, the male (890293) was started on altrenogest at a dosage of 19.8 mg orally once daily to allow reintroduction. The dosage was doubled (40 mg once a day) because of a perceived lack of response. Reintroduction to the mares occurred on 17 May 2003 with no signs of aggression noted. Treatment was reduced to 19.8 mg orally once a day and then discontinued. Altrenogest was restarted at 39.5 mg orally once a day because of the planned introduction of a new mare. There have been no major aggressive displays at this dosage of altrenogest and the dosage has recently been reduced following successful introduction of a new mare.
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Gasser, R. B., Hung, G. - C., Chilton, N. B., & Beveridge, I. (2004). Advances in developing molecular-diagnostic tools for strongyloid nematodes of equids: fundamental and applied implications. Mol Cell Probes, 18(1), 3–16.
Abstract: Infections of equids with parasitic nematodes of the order Strongylida (subfamilies Strongylinae and Cyathostominae) are of major veterinary importance. In last decades, the widespread use of drugs against these parasites has led to problems of resistance within the Cyathostominae, and to an increase in their prevalence and intensity of infection. Novel control strategies, based on improved knowledge of parasite biology and epidemiology, have thus become important. However, there are substantial limitations in the understanding of fundamental biological and systematic aspects of these parasites, which have been due largely to limitations in their specific identification and diagnosis using traditional, morphological approaches. Recently, there has been progress in the development of DNA-based approaches for the specific identification of strongyloids of equids for systematic studies and disease diagnosis. The present article briefly reviews information on the classification, biology, pathogenesis, epidemiology of equine strongyloids and the diagnosis of infections, highlights knowledge gaps in these areas, describes recent advances in the use of molecular techniques for the genetic characterisation, specific identification and differentiation of strongyloids of equids as a basis for fundamental investigations of the systematics, population biology and ecology.
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