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Sanga, U., Provenza, F. D., & Villalba, J. J. (2011). Transmission of self-medicative behaviour from mother to offspring in sheep. Anim. Behav., 82(2), 219–227.
Abstract: Herbivores challenged by diets with high concentrations of tannins learn by individual experience to self-select medicinal compounds such as polyethylene glycol (PEG), which neutralizes the negative postingestive effects of tannins. We investigated the transmission of this acquired self-medicative behaviour from mother to offspring. One group of ewes (experienced, N = 8) was conditioned to associate the beneficial effects of PEG after consuming a tannin-rich diet. Ewes ingested a meal of high-tannin food and were then offered PEG. Subsequently, ewes ingested the same tannin-rich meal and were then offered a food (grape pomace; control) that did not have the medicinal effects of PEG. After conditioning, the experienced group and a naïve group of ewes (N = 8) were given a choice between the high-tannin food, PEG and grape pomace. Experienced ewes showed higher intake and preference for PEG than did naïve ewes (P < 0.05). Subsequently, experienced and naïve ewes with their naïve lambs, as well as a group of naïve lambs without their mothers (N = 8), were exposed to the tannin-rich diet, PEG and grape pomace. Lambs were then tested for their ability to self-medicate with PEG by offering them a choice between the tannin-rich diet, PEG and grape pomace. Lambs from experienced and naïve mothers showed a higher preference for PEG than did lambs exposed without their mothers (P = 0.05). Thus, the presence of the mother (experienced or naïve) was important for naïve lambs to learn about the medicinal benefits of PEG. We conclude that the mother's presence per se may increase the efficiency of creating new knowledge, such as preference for a medicine, within a group, beyond transmitting and maintaining this knowledge across generations.
Keywords: feeding; food selection; Ovis aries; polyethylene glycol; sheep; tannins
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Sankey, C., Henry, S., André, N., Richard-Yris, M. - A., & Hausberger, M. (2011). Do Horses Have a Concept of Person? PLoS ONE, 6(3), e18331 EP -.
Abstract: <sec> <title>Background</title> <p>Animals' ability for cross-modal recognition has recently received much interest. Captive or domestic animals seem able to perceive cues of human attention and appear to have a multisensory perception of humans.</p> </sec> <sec> <title>Methodology/Principal Findings</title> <p>Here, we used a task where horses have to remain immobile under a vocal order to test whether they are sensitive to the attentional state of the experimenter, but also whether they behave and respond differently to the familiar order when tested by a familiar or an unknown person. Horses' response varied according to the person's attentional state when the order was given by an unknown person: obedience levels were higher when the person giving the order was looking at the horse than when he was not attentive. More interesting is the finding that whatever the condition, horses monitored much more and for longer times the unknown person, as if they were surprised to hear the familiar order given by an unknown voice.</p> </sec> <sec> <title>Conclusion/Significance</title> <p>These results suggest that recognition of humans may lie in a global, integrated, multisensory representation of specific individuals, that includes visual and vocal identity, but also expectations on the individual's behaviour in a familiar situation.</p> </sec>
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Sankey, C., Henry, S., Clouard, C., Richard-Yris, M. - A., & Hausberger, M. (2011). Asymmetry of behavioral responses to a human approach in young naive vs. trained horses. Physiology & Behavior, 104(3), 464–468.
Abstract: The aim of this study was to investigate the impact of training experience on young horses (Equus caballus)’ lateralized responses to an approaching human. The results show that the one year old untrained horses display asymmetrical responses to an approaching human, with more negative reactions (escapes, threats) when approached from the left side, while approaches towards the right shoulder elicited more positive behaviors. On the contrary, two years old trained horses reacted equally positively to approaches and contact on both sides. Our findings support those of previous studies investigating a link between emotionality and laterality and confirm the role of the left hemisphere in the processing of novel or negative stimuli. Moreover, the data underline the impact work and training can have on this laterality in horses.
Keywords: Laterality; Emotionality; Human approach; Horse
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Schmidt, J., Scheid, C., Kotrschal, K., Bugnyar, T., & Schloegl, C. (2011). Gaze direction – A cue for hidden food in rooks (Corvus frugilegus)? Behavioural Processes, 88(2), 88–93.
Abstract: Other individual's head- and eye-directions can be used as social cues indicating the presence of important events. Among birds, ravens and rooks have been shown to co-orient with conspecifics and with humans by following their gaze direction into distant space and behind visual screens. Both species use screens to cache food in private; also, it had been suggested that they may rely on gaze cues to detect hidden food. However, in an object-choice task, ravens failed to do so, and their competitive lifestyle may have prevented them from relying on these cues. Here we tested closely related and cooperative rooks. Food was hidden in one of two cups and the experimenter gazed at the baited cup. In a second experiment, we aimed to increase the birds’ motivation to choose correctly by increasing the investment needed to obtain the reward. To do so, the birds had to pull on a string to obtain the cup. Here, the birds as a group tended to rely on gaze cues. In addition, individual birds quickly learned to use the cue in both experiments. Although rooks may not use gaze cues to find hidden food spontaneously, they may quickly learn to do so.
Keywords: Gaze; Object choice; Corvids; Effort; Rooks
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Schnerr, C. U. (2011). Feldstudie zur Epidemiologie und Bekämpfung von Strongyliden in Pferdebeständen im Raum Baden- Württemberg. Ph.D. thesis, , .
Abstract: In der Zeit von April 2005 bis März 2006 wurden bei 105 Pferden monatlich
koprologische Untersuchungen durchgeführt. Die Pferde waren zu zwei Drittel Jungtiere (≤ 4 Jahre) und ein Drittel > 4 Jahre. Die zur Verfügung stehenden vier Betriebe befanden sich alle im Raum Baden-Württemberg. Die Kotproben wurden mit Hilfe der Flotation auf Magen-Darmnematoden untersucht und anschließend einer quantitativen Eizahlbestimmung nach Mc Master unterzogen. Ab einem Eigehalt von 250 Eiern pro Gramm Kot (EpG) wurden die Pferde entsprechend der Gruppenzugehörigkeit entweder mit Pyrantel oder Ivermectin behandelt. Es wurden bei 73 Pferden ausschließlich Strongylideneier nachgewiesen; bei vier Pferden waren in der Flotation zusätzlich Eier von Parascaris equorum zu finden. Bei 28 (26,7%) der untersuchten Pferde wurden in keiner der 12 untersuchten Proben Eier von Magen-Darmnematoden nachgewiesen. Insgesamt mussten 57 (54,3%) der Pferde über den gesamten Untersuchungszeitraum hinweg nicht behandelt werden. 48 (45,7%) Pferde mussten mindestens einmal anthelminthisch behandelt werden. Kein Pferd musste häufiger als dreimal behandelt werden. In den Monaten August bis November war der Anteil an positiven Proben der Jungtiere signifikant höher als bei den Pferden > 4 Jahre. Innerhalb der Jungtiergruppe nahm die Höhe der Strongyliden-Eiausscheidung mit zunehmendem Alter signifikant ab. Ebenso nahm die Anzahl der positiven Proben im Laufe des Untersuchungszeitraums signifikant ab. Die beiden zur Entwurmung eingesetzten Substanzen (Pyrantel und Ivermectin) waren voll wirksam. In 98,8% der untersuchten Proben war ein Rückgang der Ei-Ausscheidung noch vier Wochen nach der Behandlung auf 0 EpG nachweisbar, d. h. es gab keinerlei Anzeichen für das Vorliegen von Resistenzen gegen die eingesetzten Substanzen. Die vorliegenden Untersuchungen sind ein weiterer Beweis dafür, dass mit Hilfe der selektiven anthelminthischen Behandlung die Anzahl der Entwurmungen – insbesondere auch bei Jungtieren – deutlich gesenkt werden kann. Die Eiausscheidung und damit die Weidekontamination werden mit Hilfe dieses Verfahrens deutlich reduziert. [Between April 2005 and March 2006 monthly koprological examinations where carried out on 105 horses. Two third of the horses were young animals (≤ 4 years) and a third were > 4 years old. The four farms on hand were all located in the Baden- Württemberg area. Faecal samples were examined for gastro-intestinal nematodes by means of flotation and subsequently subjected to an egg-quantity counting according to Mc Master. Starting from an egg content of 250 eggs per gram faeces (EpG), the horses were treated with either Pyrantel or Ivermectin according to their group affiliation. In 73 horses solely Strongyle eggs were detected; the flotation of four horses additionaly showed eggs of Parascaris equorum. In 28 (26,7%) of the examined horses none of the 12 examined samples showed eggs of gastro-intestinal nematodes. Overall 57 (54,3%) horses didn´t need any treatment during the total examination cycle. 48 (45,7%) of the horses needed at least one anthelminthic treatment. None of the horses needed to be treated more than three times. From August to November the rate of positive samples within the group of young animals was significantly higher than in the horses > 4 years. Whithin the group of young animals the level of Strongyle egg excretions dropped significantly with advancing age. Likewise, the number of positive samples also dropped significantly in the course of the examination cycle. Both substances (Pyrantel and Ivermectin) applied for deworming were fully effective. Even a further 4 weeks after treatment the examined sample showed a drop of egg excretion to 0 EpG in 98,8% of the samples, in other words there were no signs of prevailing resistance appearances towards the applied substance. The present studies are further proof that the number of dewormings-especially in young animals can be distinctly reduced by means of selective anthelminthic treatments. Egg excretion and therewith pasture land contamination can be clearly reduced by means of this procedure.] |
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Sheriff, M. J., Dantzer, B., Delehanty, B., Palme, R., & Boonstra, R. (2011). Measuring stress in wildlife: techniques for quantifying glucocorticoids. Oecologia, 166(4), 869–887.
Abstract: Stress responses play a key role in allowing animals to cope with change and challenge in the face of both environmental certainty and uncertainty. Measurement of glucocorticoid levels, key elements in the neuroendocrine stress axis, can give insight into an animal’s well-being and can aid understanding ecological and evolutionary processes as well as conservation and management issues. We give an overview of the four main biological samples that have been utilized [blood, saliva, excreta (feces and urine), and integumentary structures (hair and feathers)], their advantages and disadvantages for use with wildlife, and some of the background and pitfalls that users must consider in interpreting their results. The matrix of choice will depend on the nature of the study and of the species, on whether one is examining the impact of acute versus chronic stressors, and on the degree of invasiveness that is possible or desirable. In some cases, more than one matrix can be measured to achieve the same ends. All require a significant degree of expertise, sometimes in obtaining the sample and always in extracting and analyzing the glucocorticoid or its metabolites. Glucocorticoid measurement is proving to be a powerful integrator of environmental stressors and of an animal’s condition.
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Slater, C., & Dymond, S. (2011). Using differential reinforcement to improve equine welfare: Shaping appropriate truck loading and feet handling. Behav. Process., 86(3), 329–339.
Abstract: Inappropriate behavior during common handling procedures with horses is often subject to aversive treatment. The present study replicated and extended previous findings using differential reinforcement to shape appropriate equine handling behavior. In Study 1, a multiple baseline across subjects design was used with four horses to determine first the effects of shaping target-touch responses and then successive approximations of full truck loading under continuous and intermittent schedules of reinforcement. Full loading responses were shaped and maintained in all four horses and occurrences of inappropriate behaviors reduced to zero. Generalization of the loading response was also observed to both a novel trainer and trailer. In Study 2, a changing criterion design was used to increase the duration of feet handling with one horse. The horse's responding reached the terminal duration criterion of 1 min and showed consistent generalization and one-week maintenance. Overall, the results of both studies support the use of applied equine training systems based on positive reinforcement for increasing appropriate behavior during common handling procedures.
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Steidele, N. (2011). Beobachtungen einer Przewalski-Junggesellenherde im Jahresverlauf unter besonderer Berücksichtigung von Ruheverhalten und Rangordnung.
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Stenglein, J. L., Waits, L. P., Ausband, D. E., Zager, P., & Mack, C. M. (2011). Estimating gray wolf pack size and family relationships using non invasive genetic sampling at rendezvous sites. J Mammal, 92.
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Stuber, G. D., Sparta, D. R., Stamatakis, A. M., van Leeuwen, W. A., Hardjoprajitno, J. E., Cho, S., et al. (2011). Excitatory transmission from the amygdala to nucleus accumbens facilitates reward seeking. Nature, advance online publication.
Abstract: The basolateral amygdala (BLA) has a crucial role in emotional learning irrespective of valence1, 2, 3, 4, 5, 21, 22, 23. The BLA projection to the nucleus accumbens (NAc) is thought to modulate cue-triggered motivated behaviours4, 6, 7, 24, 25, but our understanding of the interaction between these two brain regions has been limited by the inability to manipulate neural-circuit elements of this pathway selectively during behaviour. To circumvent this limitation, we used in vivo optogenetic stimulation or inhibition of glutamatergic fibres from the BLA to the NAc, coupled with intracranial pharmacology and ex vivo electrophysiology. Here we show that optical stimulation of the pathway from the BLA to the NAc in mice reinforces behavioural responding to earn additional optical stimulation of these synaptic inputs. Optical stimulation of these glutamatergic fibres required intra-NAc dopamine D1-type receptor signalling, but not D2-type receptor signalling. Brief optical inhibition of fibres from the BLA to the NAc reduced cue-evoked intake of sucrose, demonstrating an important role of this specific pathway in controlling naturally occurring reward-related behaviour. Moreover, although optical stimulation of glutamatergic fibres from the medial prefrontal cortex to the NAc also elicited reliable excitatory synaptic responses, optical self-stimulation behaviour was not observed by activation of this pathway. These data indicate that whereas the BLA is important for processing both positive and negative affect, the glutamatergic pathway from the BLA to the NAc, in conjunction with dopamine signalling in the NAc, promotes motivated behavioural responding. Thus, optogenetic manipulation of anatomically distinct synaptic inputs to the NAc reveals functionally distinct properties of these inputs in controlling reward-seeking behaviours.
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