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Schino, G., di Sorrentino, E. P., & Tiddi, B. (2007). Grooming and coalitions in Japanese macaques (<em>Macaca fuscata</em>): Partner choice and the time frame reciprocation. Journal of Comparative Psychology, 121(2), 181–188.
Abstract: Evidence of a reciprocal exchange of grooming and agonistic support in primates is mixed. In this study, the authors analyzed a large database of grooming and coalitions in captive female Japanese macaques (Macaca fuscata) to investigate their within-group distribution and temporal relations. Macaques groomed preferentially those individuals that groomed them most and supported preferentially those individuals that supported them most. They also supported preferentially those individuals that groomed them most and groomed preferentially those individuals that supported them most. These results were not explained by covariation of grooming and support with third variables such as kinship, rank, or time spent in proximity. However, receiving grooming did not increase the short-term probability of supporting a partner, and being supported did not increase the short-term probability of grooming a partner. The proximate mechanisms underlying the exchange of services were discussed in relation to the time frame of the behavioral choices made by the monkeys. (PsycINFO Database Record (c) 2012 APA, all rights reserved)
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Langbein, J., Nurnberg, G., Puppe, B., & Manteuffel, G. (2006). Self-Controlled Visual Discrimination Learning of Group-Housed Dwarf Goats (Capra hircus): Behavioral Strategies and Effects of Relocation on Learning and Memory. J. Comp. Psychol., 120(1), 58–66.
Abstract: In most studies on animal learning, individual animals are tested separately in a specific learning environment and with a limited number of trials per day. An alternative approach is to test animals in a familiar environment in their social group. In this study, the authors--applying a fully automated learning device--investigated voluntary, self-controlled visual shape discrimination learning of group-housed dwarf goats (Capra hircus). The majority of the tested goats showed successful shape discrimination, which indicates the adaptive value of an effective learning strategy. However, in each group, a few individual goats developed behavioral strategies different from shape discrimination to get reward. Relocation impairs memory retrieval (probably by attention shifting) only temporarily for previously learnt shapes. The results demonstrate the usefulness of a self-controlled learning paradigm to assess learning abilities of social species in their normal social settings. This may be especially relevant for captive animals to improve their welfare.
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Jørgensen, G. H. M., Borsheim, L., Mejdell, C. M., Søndergaard, E., & Bøe, K. E. (2009). Grouping horses according to gender--Effects on aggression, spacing and injuries. Appl. Anim. Behav. Sci., 120(1-2), 94–99.
Abstract: Many horse owners tend to group horses according to gender, in an attempt to reduce aggressive interactions and the risk of injuries. The aim of our experiment was to test the effects of such gender separation on injuries, social interactions and individual distance in domestic horses. A total of 66 horses were recruited from 4 different farms in Norway and Denmark and divided into six batches. Within each batch, horses were allotted into one mare group, one gelding group and one mixed gender group, with most groups consisting of three or four animals. After 4-6 weeks of acclimatisation, a trained observer recorded all social interactions using direct, continuous observation 1 h in the morning and 1 h in the afternoon for three consecutive days. Recordings of the nearest neighbour of each horse were performed using instantaneous sampling every 10 min. The horses were inspected for injuries before grouping, day 1 after grouping and after 4-6 weeks. No significant effect of gender composition was found on social interactions (P > 0.05), spacing (P > 0.07) or injuries (P > 0.23). Eighty percent of all aggressive interactions recorded were threats, not involving physical contact. Horses with the smallest space allowance showed the highest mean number of aggressive interactions (28.6 ± 6.1 interactions per 6 h) compared to the mean of all the other batches (8.3 ± 1.0 interactions per 6 h). Very few injuries were found and most were superficial. In conclusion, gender composition does not seem to have any effect on aggression level, spacing or injuries. However, the early social experience of horses, management of feeding and space allowance probably represents more important factors for successful group housing of domestic horses.
Keywords: Horse; Group housing; Gender; Injuries; Social behaviour
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Miklosi, A., Pongracz, P., Lakatos, G., Topal, J., & Csanyi, V. (2005). A Comparative Study of the Use of Visual Communicative Signals in Interactions Between Dogs (Canis familiaris) and Humans and Cats (Felis catus) and Humans. J. Comp. Psychol., 119(2), 179–186.
Abstract: Dogs' (Canis familiaris) and cats' (Felis catus) interspecific communicative behavior toward humans was investigated. In Experiment 1, the ability of dogs and cats to use human pointing gestures in an object-choice task was compared using 4 types of pointing cues differing in distance between the signaled object and the end of the fingertip and in visibility duration of the given signal. Using these gestures, both dogs and cats were able to find the hidden food; there was no significant difference in their performance. In Experiment 2, the hidden food was made inaccessible to the subjects to determine whether they could indicate the place of the hidden food to a naive owner. Cats lacked some components of attention-getting behavior compared with dogs. The results suggest that individual familiarization with pointing gestures ensures high-level performance in the presence of such gestures; however, species-specific differences could cause differences in signaling toward the human.
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Muscatello, G., Gilkerson, J. R., & Browning, G. F. (2007). Comparison of two selective media for the recovery, isolation, enumeration and differentiation of Rhodococcus equi. Vet Microbiol, 119(2-4), 324–329.
Abstract: The use of selective media to facilitate the isolation of Rhodococcus equi from environmental and clinical samples has aided studies of the ecology of R. equi and the epidemiology of disease caused by R. equi. Here, we compared the efficacy of two selective media (NANAT and modified CAZ-NB) for the recovery of six defined strains of R. equi and for the isolation and enumeration of both avirulent and virulent R. equi from 60 paired soil samples from horse farms using colony blotting and DNA hybridisation. No difference was found between the two media in the recoverability of defined strains of R. equi or the proportion of soil cultures positive for R. equi or virulent R. equi. NANAT medium was significantly less inhibitory of bacterial growth from soil culture compared to mCAZ-NB (P = 0.001), but there was no difference between the media in the number of R. equi colonies recovered. Soil cultured on mCAZ-NB medium yielded a significantly greater number of virulent R. equi colonies than NANAT (P = 0.03). The proportion of R. equi that were virulent in soil cultures on mCAZ-NB (32%) was more than three times that seen in cultures on NANAT (9%). Thus modified CAZ-NB appeared to be a better selective media for studies where the optimal recovery of virulent R. equi is required, such as in studies of the gastrointestinal carriage of virulent R. equi and of subclinically infected foals.
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Gallese, V., Fadiga, L., Fogassi, L., & Rizzolatti, G. (1996). Action recognition in the premotor cortex. Brain, 119(2), 593–609.
Abstract: We recorded electrical activity from 532 neurons in the rostral part of inferior area 6 (area F5) of two macaque monkeys. Previous data had shown that neurons of this area discharge during goal-directed hand and mouth movements. We describe here the properties of a newly discovered set of F5 neurons ( mirror neurons', n = 92) all of which became active both when the monkey performed a given action and when it observed a similar action performed by the experimenter. Mirror neurons, in order to be visually triggered, required an interaction between the agent of the action and the object of it. The sight of the agent alone or of the object alone (three-dimensional objects, food) were ineffective. Hand and the mouth were by far the most effective agents. The actions most represented among those activating mirror neurons were grasping, manipulating and placing. In most mirror neurons (92%) there was a clear relation between the visual action they responded to and the motor response they coded. In [~]30% of mirror neurons the congruence was very strict and the effective observed and executed actions corresponded both in terms of general action (e.g. grasping) and in terms of the way in which that action was executed (e.g. precision grip). We conclude by proposing that mirror neurons form a system for matching observation and execution of motor actions. We discuss the possible role of this system in action recognition and, given the proposed homology between F5 and human Brocca's region, we posit that a matching system, similar to that of mirror neurons exists in humans and could be involved in recognition of actions as well as phonetic gestures.
Keywords: action encoding; visual responses; premotor cortex; macaque monkey
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Edouard, N., Fleurance, G., Dumont, B., Baumont, R., & Duncan, P. (2009). Does sward height affect feeding patch choice and voluntary intake in horses? Appl. Anim. Behav. Sci., 119(3-4), 219–228.
Abstract: The numbers of horses grazing at pasture are increasing in developed countries, so a proper understanding of their feeding selectivity and of the tactics they use for extracting nutrients from swards is essential for the management of horses and grasslands. Resource acquisition in herbivores can be optimised through the modulation of their intake and patch selection, both being strongly dependent on the characteristics of swards. However, the principles by which horses adjust their grazing behaviour in response to variations in sward features are not completely understood. The aim of this study was to determine whether the behaviour of horses conforms to optimal foraging models. We hypothesized that, faced with binary choices between vegetative swards of a good and similar quality at three different heights, horses would select the taller sward, i.e. that allowing a higher reward in terms of dry matter intake rate. Three groups of three 2-year-old saddle horses were grazed on a semi-natural pasture that was managed to produce three contrasting sward heights at 6, 11 and 17 cm, in a Latin-square design. The instantaneous intake rate was determined from bite rate measured at pasture on the three sward heights, and bite mass estimated from measurements using swards offered indoors in experimental trays. Daily dry matter intake was estimated individually by total faecal collection and an estimation of digestibility from faecal nitrogen. Short-term (first 30 min) and daily preferences were assessed from the time spent grazing each sward offered in pair-wise tests at pasture. The results show that daily voluntary intake (an average of 21 g DM kg LW-1 day-1) and total grazing time (an average of 14 h day-1) were independent of sward height and of the choice of patches offered. In choice situations, the animals spent more time grazing on the taller sward, both during the first 30 min and at the daily scale. These results show that horses choose between vegetative patches of a good and similar quality according to the predictions from optimal foraging models, and select the one that they can ingest faster. Further research will now have to explore how the horses will adapt their feeding behaviour when they face a trade-off between sward height and quality.
Keywords: Patch selection; Intake; Sward height; Horse; Pasture
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Crosby, M. B., Zhang, J., Nowling, T. M., Svenson, J. L., Nicol, C. J., Gonzalez, F. J., et al. (2006). Inflammatory modulation of PPAR gamma expression and activity. Clin Immunol, 118(2-3), 276–283.
Abstract: Nitric oxide (NO) production increases with age in the lupus-prone MRL/lpr mouse, paralleling disease activity. One mechanism for excess NO production in MRL/lpr mice may be a defect in down-regulatory mechanisms of the iNOS pathway. A potential modulator of NO is the nuclear hormone receptor peroxisome proliferation activated receptor gamma (PPARgamma). We demonstrate that renal PPARgamma protein expression was altered as disease progressed in MRL/lpr mice, which paralleled increased iNOS protein expression. Additionally, MRL/lpr-derived primary mesangial cells expressed less PPARgamma than BALB/c mesangial cells and produced more NO in response to LPS and IFNgamma. Furthermore, PPARgamma activity was reduced in mesangial cells following exposure to inflammatory mediators. This activity was restored with the addition of a NOS enzyme inhibitor. These results indicate that the activation of inflammatory pathways may lead to reduced activity and expression of PPARgamma, further exacerbating the disease state.
Keywords: Age Factors; Animals; Cell Line, Transformed; Cells, Cultured; Female; Inflammation Mediators/*physiology; Kidney/metabolism; Mesangial Cells/metabolism; Mice; Mice, Inbred BALB C; Mice, Inbred C57BL; Mice, Inbred MRL lpr; Mice, Knockout; Nitric Oxide/biosynthesis; Nitric Oxide Synthase Type II/biosynthesis/genetics; PPAR gamma/*biosynthesis/*genetics/metabolism; Up-Regulation/immunology
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VanDierendonck, M. C., de Vries, H., Schilder, M. B. H., Colenbrander, B., & Þorhallsdóttir, A. G. and S., H. (2009). Interventions in social behaviour in a herd of mares and geldings. Appl. Anim. Behav. Sci., 116(1), 67–73.
Abstract: Social dynamics and maintenance of social cohesion were studied by analysing social interventions in two groups of horses consisting of adult mares, their offspring, adult geldings and sub-adults. The animals were observed for a total of 1316 h. All relevant dyadic and triadic social interactions, including initial behaviour, possible intervention and outcome, were recorded. The main question was: do horses use interventions in affiliative interactions to safeguard their social network? Horses were significantly more likely to intervene in allogrooming or play interactions that involved a preferred partner. The stronger the preferred association in allogrooming, the higher the likelihood the intervener took over allogrooming with an initial dyad member. Interveners originating from two newly introduced groups (n = 3 and 5), intervened significantly more often when a member of their own group allogroomed with an unfamiliar horse. In play, no correlation with unfamiliarity was found. Overall, the intervening horses stopped more than half of the initial allogrooming interactions, and a third of all interactions. Therefore, social facilitation cannot sufficiently explain interference behaviour. This study shows that maintaining relationships with preferred partners is important to horses and has implications for equine husbandry and management.
Keywords: Horses; Social relationships; Interventions; Mares; Geldings; Play; Allogrooming; Social network
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Biondi, L. M., García, G. O., Bó, M. S., & Vassallo, A. I. (2010). Social Learning in the Caracara Chimango, Milvago chimango (Aves: Falconiformes): an Age Comparison. Ethology, 116(8), 722–735.
Abstract: Abstract Milvago chimango is a gregarious raptor showing great ecological plasticity. Their ability to explore new resources has allowed them to survive in areas with increasing human modification. In this study, we evaluated the social learning ability in wild-caught individuals of M. chimango. In particular, we tested whether an ‘observer’ individual could improve the acquisition of a novel behaviour by watching a ‘demonstrator,’ and we examined the effects of age of both observers and demonstrators on social learning. We measured the ability of 18 observers to open an opaque Plexiglas box containing food, and we compared their performance to that of 10 control birds who did not watch a demonstrator solve the task. Prior to watching a demonstrator, only two of the observers and two of the control birds were able to open the box. After watching a demonstrator, 67% of observers were able to open the box, outperforming control birds in speed and success. Juvenile observers were more successful and faster than adults at contacting and opening the box. The age of the demonstrator did not influence the observers’ likelihood of success. These results showed that M. chimango are able to learn a box-opening task with a hidden food reward by observing the behaviour of a conspecific and that this behaviour persisted over several days. Social learning ability in M. chimango might allow certain behavioural patterns, such as those related to novel resource acquisition in modified environments, to be socially transmitted among individuals in a population.
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