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Griebenow, K., & Klibanov, A. M. (1995). Lyophilization-induced reversible changes in the secondary structure of proteins. Proc Natl Acad Sci USA, 92(24), 10969–10976.
Abstract: Changes in the secondary structure of some dozen different proteins upon lyophilization of their aqueous solutions have been investigated by means of Fourier-transform infrared spectroscopy in the amide III band region. Dehydration markedly (but reversibly) alters the secondary structure of all the proteins studied, as revealed by both the quantitative analysis of the second derivative spectra and the Gaussian curve fitting of the original infrared spectra. Lyophilization substantially increases the beta-sheet content and lowers the alpha-helix content of all proteins. In all but one case, proteins become more ordered upon lyophilization.
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Pawluski, J., Jego, P., Henry, S., Bruchet, A., Palme, R., Coste, C., et al. (2017). Low plasma cortisol and fecal cortisol metabolite measures as indicators of compromised welfare in domestic horses (Equus caballus). Plos One, 12(9), e0182257.
Abstract: The hypothalamic-pituitary-adrenal (HPA) axis response to chronic stress is far from straight forward, particularly with regards to animal welfare. There are reports of no effect as well as both decreases and increases in cortisol after chronic stressors. Therefore, the first aim of the present study was to determine how measures of compromised welfare, such as chronic pain and haematological anomalies, related to cortisol levels in domestic horses (Equus caballus). Domestic horses are an informative model to investigate the impact of chronic stress (due to environment, pain, work, housing conditions...) on the HPA axis. The second aim was to determine whether levels of fecal cortisol metabolites (FCM) may be used as an indicator of welfare measures. The present study used fifty-nine horses (44 geldings and 15 mares), from three riding centres in Brittany, France. The primary findings show that horses whose welfare was clearly compromised (as indicated by an unusual ears backward position, presence of vertebral problems or haematological anomalies, e.g. anaemia) also had lower levels of both FCM and plasma cortisol. This work extends our previous findings showing that withdrawn postures, indicators of depressive-like behavior in horses, are associated with lower plasma cortisol levels. We also found that evening plasma cortisol levels positively correlated with FCM levels in horses. Future research aims to determine the extent to which factors of influence on welfare, such as living conditions (e.g. single stalls versus group housing in pasture or paddocks), early life factors, and human interaction, act as mediators of cortisol levels in horses.
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Baragli, P., Paoletti, E., Vitale, V., & Sighieri, C. (2011). Looking in the correct location for a hidden object: brief note about the memory of donkeys (Equus asinus). Ethology Ecology & Evolution, 23(2), 187–192.
Abstract: In recent years, considerable literature has been published on cognition in horses; however, much less is known about the cognitive abilities of domestic donkey (Equus asinus). This study aimed to expand our knowledge of donkey cognition by assessing their short-term memory capacity. We employed a detour problem combined with the classic delayed-response task, which has been extensively used to compare working memory duration in a variety of different species. A two-point choice apparatus was used to investigate location recall and search behaviour for a food target, after a short delay following its disappearance. Four donkeys completed the task with a 10 sec delay, while four others were tested with a 30 sec delay. Overall, each group performed above chance level on the test, showing that subjects had successfully encoded, maintained, and retrieved the existence and location of the target despite the loss of visual contact.
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Pfammatter, M., Huwiler, S., Kägi, F., Kopp, C., Krüger, K., & Herholz, C. (2017). Leistung und Stresslevel bei Maultieren während eines fünftägigen Gotthardtrecks [Performance et niveau de stress chez les mulets durant un trek de cinq jours sur le Gothard][Muli: prestazione e livello di stress durante una traversata del Gottardo di 5 giorni][Performance and stress level in mules during a five days Gotthard trek]. Agrarforschung Schweiz, 8((7-8)), 276–283.
Abstract: Während einer fünftägigen Gotthardüberquerung im Sommer 2016 haben drei Maultiere als Tragtiere mit einer Gepäcklast von je 80 kg rund 94,46 Kilometer und 3�364 Höhenmeter bewältigt. Die Leistungsanforderung wurde anhand der Erholungswerte der Vitalparameter Herzfrequenz, Atemfrequenz und Körpertemperatur, sowie durch kontinuierliche Herzfrequenzmessung während der Belastung evaluiert. Die Bestimmung der Glucokortikoid- Metabolit Konzentration im Kot diente zur Einschätzung des Stresslevels der drei Maultiere. Die Erholungswerte der Herzfrequenzen der drei Maultiere lagen während allen Trekkingetappen in einem Bereich, der nicht auf eine Leistungsüberforderung schliessen liess. Anhand der kontinuierlichen Herzfrequenzaufzeichnung bei einem der Maultiere konnte gezeigt werden, dass die physische Leistungsanforderung im Ausdauerbereich lag. Wie als normale physiologische Reaktion des Körpers nach einer fünftägigen körperlichen Belastung erwartet, stieg Stresslevel gemessen an den Glucokortikoid- Metaboliten im Kot gegen Ende des Trecks bei allen Maultieren an. In der vorliegenden Studie konnte gezeigt werden, dass die Maultiere während des Gotthardtrecks ausdauernd belastbar waren, ohne durch die Anstrengung beeinträchtigt zu sein, die schon historisch von Maultieren abverlangt wurde.[
Durant une traversée du Gothard de cinq jours pendant l�été 2016, trois mulets ont été employés comme animaux de bât pour porter une charge de 80 kg sur 94,46 km, avec un dénivelé de 3364 m. Les exigences de performance ont été évaluées à partir des valeurs de récupération des paramètres vitaux (fréquence cardiaque, fréquence respiratoire et température corporelle) et de la fréquence cardiaque durant l�effort. La concentration en métabolites glucocorticoïdes dans le crottin a permis d�estimer le niveau de stress des trois animaux. Durant toute la durée du trek, les valeurs de récupération de la fréquence cardiaque des trois mulets étaient comprises dans un intervalle n�indiquant aucun effort excessif. La mesure constante des pulsations cardiaques a montré que l�intensité des performances physiques de ces animaux ne sortait pas de leur zone d�endurance. Comme on pouvait s�y attendre, le niveau de stress mesuré par le biais des métabolites glucocorticoïdes a augmenté chez tous les mulets à la fin du trek, réaction physiologique normale du corps après un effort de cinq jours. La présente étude a montré que durant un trek sur le Gothard, les mulets ont fait preuve d�endurance et de résistance, sans altération due à l�effort que l�on exige traditionnellement de leur part.][Nell�estate del 2016 tre muli impiegati come animali da soma hanno attraversato il Gottardo portando un carico di 80 kg ciascuno e percorrendo in cinque giorni un percorso di circa 94,46 chilometri con un dislivello di 3364 metri. La prestazione è stata valutata sulla base dei valori di recupero dei parametri vitali (frequenza cardiaca, frequenza respiratoria, temperatura corporea) e misurando costantemente la frequenza cardiaca sotto sforzo. Il livello di stress dei tre muli è stato valutato in funzione della concentrazione di metaboliti glicocorticoidi riscontrata nelle feci. In tutte le tappe del trekking i valori di recupero della frequenza cardiaca registrati nei muli rientravano in un intervallo che non lasciava supporre un sovraccarico. Sulla base della registrazione costante della frequenza cardiaca di uno dei tre muli è stato possibile dimostrare che l�intensità dello sforzo fisico non superava il loro intervallo di resistenza. Come previsto, verso la fine del trekking la concentrazione di metaboliti glicocorticoidi nelle feci di tutti e tre i muli indicava un aumento del livello di stress; si tratta di una reazione fisiologica normale dopo uno sforzo fisico di cinque giorni. Questo studio ha dimostrato che lo sforzo sopportato dai muli per portare un carico attraverso il Gottardo, un compito da secoli richiesto a questi animali, rientrava nel loro intervallo di resistenza e non ha avuto ripercussioni negative sul loro fisico.][In the summer of 2016, three pack mules, each carrying a load weighing 80kg, accompanied a 94.46km trek across the Gotthard Pass with a total altitude difference of 3,364m. The mules� performances were evaluated by measuring vital recovery parameters such as heart- and respiratory rates and body temperature, and by continuous heartrate monitoring during the trek. The stress levels of the animals were estimated by determining glucocorticoid metabolite levels in their faeces. Throughout the trekking days, recovery heartrates lay within a range which indicated that the animals were not being overworked. The continuous heartrate monitoring of one of the mules showed that its physical performance lay within the endurance zone. As expected, glucocorticoid metabolite levels were elevated in the faeces of all the mules � a normal physiological response after five consecutive days of exercise. The study shows the mules as being capable of performing at an endurance level during the Gotthard trek with no adverse affects on their health � a performance which was historically expected of the animals.]
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Horner, V., & Whiten, A. (2007). Learning from others' mistakes limits on understanding a trap-tube task by young chimpanzees (Pan troglodytes) and children (Homo sapiens). J Comp Psychol, 121(1), 12–21.
Abstract: A trap-tube task was used to determine whether chimpanzees (Pan troglodytes) and children (Homo sapiens) who observed a model's errors and successes could master the task in fewer trials than those who saw only successes. Two- to 7-year-old chimpanzees and 3- to 4-year-old children did not benefit from observing errors and found the task difficult. Two of the 6 chimpanzees developed a successful anticipatory strategy but showed no evidence of representing the core causal relations involved in trapping. Three- to 4-year-old children showed a similar limitation and tended to copy the actions of the demonstrator, irrespective of their causal relevance. Five- to 6-year-old children were able to master the task but did not appear to be influenced by social learning or benefit from observing errors.
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Byrne, R. W., & Russon, A. E. (1998). Learning by imitation: a hierachical approach. Behav. Brain Sci., 21, 667–721.
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Harlow, H. F. (1950). Learning and satiation of response in intrinsically motivated complex puzzle performance by monkeys. J Comp Physiol Psychol, 43(4), 289–294.
Abstract: Two rhesus monkeys, given 60 two-hour sessions with a six-device mechanical puzzle showed clear evidence of learning, the curve showing ratio of incorrect to correct responses appearing quite comparable to similar curves obtained during externally rewarded situations. When, on the thirteenth day of tests, the subjects were presented with the puzzle 100 times at 6-minute intervals, the number of devices manipulated decreased regularly throughout the day, although there was no significant change in the number of times the problem assembly was attacked.
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Thorpe, W. H. (1963). Learning and Instinct in Animals. London: Methuen.
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Mech L.D. (2000). Leadership in Wolf, Canis lupus, Packs. Can Field Nat, 114(2), 259–263.
Abstract: I examine leadership in Wolf (Canis lupus) packs based on published observations and data gathered during summers from 1986 to 1998 studying a free-ranging pack of Wolves on Ellesmere Island that were habituated to my presence. The breeding male tended to initiate activities associated with foraging and travel, and the breeding female to initiate, and predominate in, pup care and protection. However, there was considerable overlap and interaction during these activities such that leadership could be considered a joint function. In packs with multiple breeders, quantitative information about leadership is needed.
Keywords: Wolf, Canis lupus, leadership, behavior, foraging, movements, pup care, provisioning, sociality, reproduction, breeding, Northwest Territories.
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Karenina, K., Giljov, A., Ingram, J., Rowntree, V. J., & Malashichev, Y. (2017). Lateralization of mother�infant interactions in a diverse range of mammal species. Nat Ecol Evol, 1, 0030 Ep -.
Abstract: Left-cradling bias is a distinctive feature of maternal behaviour in humans and great apes, but its evolutionary origin remains unknown. In 11 species of marine and terrestrial mammal, we demonstrate consistent patterns of lateralization in mother�infant interactions, indicating right hemisphere dominance for social processing. In providing clear evidence that lateralized positioning is beneficial in mother�infant interactions, our results illustrate a significant impact of lateralization on individual fitness.
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