12 research outputs found
Le sevrage : quelles sont les recommandations issues de la recherche Ă©quine ?
National audienc
La peau de la face chez la poule change de couleur en fonction des situations Ă©motionnelles
National audienceLes changements de couleur de la peau du visage par afflux sanguin sont des marqueurs dâĂ©motions chez lâHomme. Cette capacitĂ© des parties de peau dĂ©nudĂ©es Ă changer transitoirement de couleur a Ă©tĂ© dĂ©crite chez plusieurs espĂšces dâoiseaux. Cependant, elle nâa jamais Ă©tĂ© Ă©tudiĂ©e dans le cadre des Ă©motions, Ă lâexception dâune expĂ©rience portant sur les interactions positives soigneur-animal chez le Ara bleu (Ara ararauna). Dans cette Ă©tude, nous avons cherchĂ© Ă savoir si la poule domestique (Gallus gallusdomesticus) Ă©tait capable de changer de couleur de peau en fonction du contexte Ă©motionnel dans lequel elle Ă©tait.LâĂ©tude a portĂ© sur deux races de poules rustiques juvĂ©niles (PĂ©kins n=10, et Meusiennes n=7), maintenues en semi-libertĂ©. Elles ont Ă©tĂ© filmĂ©es dans des situations Ă valeurs Ă©motionnelles contrastĂ©es : Bain de poussiĂšre, test de RĂ©compense (valence positive de forte intensitĂ©) ; Toilettage, Repos, Mange (valence positive de faible intensitĂ©) ; Alerte, test de Capture (valence nĂ©gative de forte intensitĂ©). Des images ont Ă©tĂ© extraites de ces films Ă partir desquelles le taux de rouge des zones dĂ©nudĂ©es de la face (crĂȘte, barbillon, oreillon, joue) a Ă©tĂ© mesurĂ© (environ 30 images/poule/situation). Il existe une interaction significative entre les situations et les zones dâintĂ©rĂȘt pour la variation du taux de rouge chez les deux races (Meusiennes : p=0,002, PĂ©kins : p=0,0003). Quelle que soit la zone, le taux de rouge varie de maniĂšre significative en fonction du contexte Ă©motionnel. La joue est la rĂ©gion oĂč les situations sont le plus nettement dissociĂ©es : le taux de rouge est significativement plus important pour les situations Alerte, Capture et RĂ©compense que pour Repos, Mange et Toilettage. Le Bain de poussiĂšre est significativement diffĂ©rent des autres situations avec un taux de rouge intermĂ©diaire chez les Meusiennes, alors quâil nâest significativement pas diffĂ©rent de Alerte et RĂ©compense chez les PĂ©kins. La couleur de la peau de la face est donc plus claire dans les situations Ă valence Ă©motionnelle positive de faible intensitĂ© et plus rouge pour les Ă©motions de forte intensitĂ©. De plus, il semblerait quâelle soit plus rouge pour les Ă©motions nĂ©gatives de forte intensitĂ© que pour les Ă©motions positives de forte intensitĂ©
Patients Lung Derived Tumoroids (PLDTs) to model therapeutic response
International audiencePreclinical lung cancer models are essential for a basic understanding of lung cancer biology and its translation into efficient treatment options for affected patients. Lung cancer cell lines and xenografts derived directly from human lung tumors have proven highly valuable in fundamental oncology research and anticancer drug discovery. Both models inherently comprise advantages and caveats that have to be accounted for. Recently, we have enabled reliable in vitro culture techniques from lung cancer biopsies as Patients Lung Derived Tumoroids (PLDTs). This breakthrough provides the possibility of high-throughput drug screening covering the spectrum of lung cancer phenotypes seen clinically. We have adapted and optimized our in vitro three-dimensional model as a preclinical lung cancer model to recapitulate the tumor microenvironment (TME) using matrix reconstitution. Hence, we developed directly PLDTs to screen for chemotherapeutics and radiation treatment. This original model will enable precision medicine to become a reality, allowing a given patient sample to be screened for effective ex vivo therapeutics, aiming at tailoring of treatments specific to that individual. Hence, this tool can enhance clinical outcomes and avoid morbidity due to ineffective therapies
Le changement de couleur de la peau de la face chez la poule est un marqueur dâĂ©motions
National audienceLes changements de couleur de la peau du visage par afflux sanguin sont des marqueurs dâĂ©motions chez lâHomme. Cette capacitĂ© des parties de peau dĂ©nudĂ©es Ă changer transitoirement de couleur a Ă©tĂ© dĂ©crite chez plusieurs espĂšces dâoiseaux. Cependant, elle nâa jamais Ă©tĂ© Ă©tudiĂ©e dans le cadre des Ă©motions, Ă lâexception dâune expĂ©rience portant sur les interactions positives soigneur-animal chez le Ara bleu (Ara ararauna). Dans cette Ă©tude, nous avons cherchĂ© Ă savoir si la poule domestique (Gallus gallus domesticus) Ă©tait capable de changer de couleur de peau en fonction du contexte Ă©motionnel dans lequel elle Ă©tait. LâĂ©tude a portĂ© sur deux races de poules rustiques juvĂ©niles (PĂ©kins n=10, et Meusiennes n=7), maintenues en semi-libertĂ©. Elles ont Ă©tĂ© filmĂ©es dans des situations Ă valeurs Ă©motionnelles contrastĂ©es : Bain de poussiĂšre, test de RĂ©compense (valence positive de forte intensitĂ©) ; Toilettage, Repos, Mange (valence positive de faible intensitĂ©) ; Alerte, test de Capture (valence nĂ©gative de forte intensitĂ©). Des images ont Ă©tĂ© extraites de ces films Ă partir desquelles le taux de rouge des zones dĂ©nudĂ©es de la face (crĂȘte, barbillon, oreillon, joue) a Ă©tĂ© mesurĂ© (environ 30 images/poule/situation). Il existe une interaction significative entre les situations et les zones dâintĂ©rĂȘt pour la variation du taux de rouge chez les deux races (Meusiennes : p=0,002, PĂ©kins : p=0,0003). Quelle que soit la zone, le taux de rouge varie de maniĂšre significative en fonction du contexte Ă©motionnel. La joue est la rĂ©gion oĂč les situations sont le plus nettement dissociĂ©es : le taux de rouge est significativement plus important pour les situations Alerte, Capture et RĂ©compense que pour Repos, Mange et Toilettage. Le Bain de poussiĂšre est significativement diffĂ©rent des autres situations avec un taux de rouge intermĂ©diaire chez les Meusiennes, alors quâil nâest significativement pas diffĂ©rent de Alerte et RĂ©compense chez les PĂ©kins. La couleur de la peau de la face est donc plus claire dans les situations Ă valence Ă©motionnelle positive de faible intensitĂ© et plus rouge pour les Ă©motions de forte intensitĂ©. De plus, il semblerait quâelle soit plus rouge pour les Ă©motions nĂ©gatives de forte intensitĂ© que pour les Ă©motions positives de forte intensitĂ©. En conclusion, la couleur de la peau de la face chez la poule varie en fonction des situations Ă valeurs Ă©motionnelles contrastĂ©es. Les variations du taux de rouge de la face pourraient constituer des signaux visuels fonctionnels permettant lâexpression Ă©motionnelle au sein des groupes sociaux
La face des poules adultes change-t-elle de couleur en fonction de leurs Ă©motions ?
National audienceDes Ă©tudes rĂ©centes ont montrĂ© que les poules (Gallus gallus domesticus) juvĂ©niles modifiaient la position des plumes de leur tĂȘte et changeaient transitoirement de couleur de la peau au niveau des joues, des oreillons, des barbillons et de la crĂȘte en fonction de situations Ă©motionnelles contrastĂ©es. Cependant, lors de la maturation sexuelle, la crĂȘte et les barbillons se dĂ©veloppent et acquiĂšrent d'autres fonctions (e.g. dans les relations de dominance). Dans cette Ă©tude, nous avons cherchĂ© Ă savoir si, chez les poules adultes comme chez les juvĂ©niles, ces zones de peau prĂ©sentaient une variation de couleur lors de situations Ă©motionnelles contrastĂ©es. L'Ă©tude a portĂ© sur des poules PĂ©kins adultes (race rustique, n=12), maintenues en semi-libertĂ©. Elles ont Ă©tĂ© filmĂ©es dans des situations Ă valeurs Ă©motionnelles contrastĂ©es : Bain de poussiĂšre, test de RĂ©compense (valence positive de forte intensitĂ©) ; Toilettage, Repos, Mange (valence positive de faible intensitĂ©) ; test de Capture (valence nĂ©gative de forte intensitĂ©). Vingt images de profils ont Ă©tĂ© extraites par poule et par situation, et le taux de rouge moyen de la peau (crĂȘte, barbillon, oreillon, joue) a Ă©tĂ© mesurĂ© avec le logiciel ImageJ. Pour chacune des zones de peau, le taux de rouge a Ă©tĂ© comparĂ© entre les situations Ă l'aide d'un modĂšle linĂ©aire mixte. Les rĂ©sultats ont montrĂ© que le taux de rouge de la peau chez la poule adulte variait en fonction des situations Ă©motionnelles. Le taux de rouge est plus clair dans les situations Ă valence Ă©motionnelle positive de faible intensitĂ© comme les situations de calme et plus rouge pour les Ă©motions de forte intensitĂ©. Le changement transitoire de couleur de peau de la face serait un marqueur d'Ă©motions non invasif chez la poule aussi bien juvĂ©nile qu'adulte. Ce marqueur nous permettrait d'avoir une meilleure comprĂ©hension de la maniĂšre dont les poules, espĂšce aviaire la plus reprĂ©sentĂ©e en Ă©levage, perçoivent leur environnement. Ce changement de couleur pourrait, par exemple, ĂȘtre utilisĂ© pour Ă©valuer la qualitĂ© de la relation Humain-Animal
Lower redness of the facial skin is a marker of a positive human-hen relationship
International audienceIn certain mammals, facial expressions are reliable markers of the emotional state of an individual. In humans andparrots, emotional stimuli can induce a rapid change of face colour that is linked to blood flow. The aim of this studywas to test whether the redness of the face in domestic hens could be used as an emotional marker in the context of thehuman-hen relationship. Two groups of hens (Sussex) were studied: a group habituated to a human with daily positiveinteraction (n=13) and a non-habituated group (n=12). Behaviour and skin colour of wattles, cheeks, ear lobes andcomb were analysed from two video-recorded tests (novel environment and reactivity to human tests) conducted after5 and 6 weeks of habituation. In the novel environment test, usually used for testing general underlying fearfulness,the hens were tested alone in an unknown environment. In the reactivity to human test, the hens were tested againin this environment but with the familiar human sitting inside. The human presence should only be stressful for thenon-habituated group. As expected, the behaviour of the two groups did not differ during the novel environment test.During the reactivity to human test, the habituated hens were more relaxed than the non-habituated hens: they tooktheir first step faster (P=0.03), came faster into contact with the human (P=0.03), explored him longer (P=0.0003)and displayed more comfort behaviours (P=0.01). Face redness differed between the two groups during only thereactivity to human test: lower redness was observed in habituated hens for 3 out of the 4 regions (wattles P=0.01,cheeks P<0.0001, ear lobes P=0.0003). These results show that more relaxed hens are less red, thus face rednesscould be a reliable marker of the quality of the human-hen relationship. As such, it could be used as a tool for humanto infer the emotional state of hens and more broadly, to evaluate their welfare
Progressive habituation to separation alleviates the negative effects of weaning in the mother and foal.
Early and definitive separation between offspring and their mothers has negative consequences on behavioral and physiological responses. This study compared sudden and definitive weaning (Sudd group, N?=?16) and weaning involving progressive habituation to separation using a fence line during the month preceding definitive separation (Prog group, N?=?18). The impact of these two methods was assessed in both foals and their mothers through behavioral and biological parameters, including salivary cortisol, telomere length and blood transcriptomes. On the day of definitive separation, Prog foals neighed and trotted less and presented lower cortisol levels than Sudd foals. The weaning type also acted on the foals' personality development; Prog foals became more curious, less fearful and less gregarious than Sudd foals, and the effects remained visible for at least 3 months. In principal component analysis, the Sudd and Prog groups were well separated along a factor where fear, reactivity and gregariousness correlated with high cortisol levels, but curiosity was associated with an increased telomere length and higher expression of genes involved in mitochondrial functions. Progressive weaning was also beneficial in mares. Principal component analysis showed that most Sudd group mares had higher cortisol levels and displayed more alert postures, neighs and activity on the day of weaning, indicating higher stress levels, while Prog mares had profiles that were characterized by more time spent resting on the day of weaning and longer telomere lengths. In conclusion, this study shows that progressive habituation to separation alleviates the negative effect of definitive weaning on both the mother and her young compared to sudden separation
Alarm communication predates eusociality in termites
The vibroacoustic and chemical alarm communication in the wood roach Cryptocercus and in 20 termite species are studied to reveal that the Neoisoptera species have developed the most sophisticated communication system, which could contribute towards their ecological success
Exploration of skin redness and immunoglobulin A as markers of the affective states of hens
International audienceNon-invasive markers of affective states can help understanding animals' perception of situations and improving their welfare. These markers are scarce in avian species. In this study, we investigate the potential relation between alterations in facial skin redness in hens and their corresponding affective states. Six hens were filmed in both naturally unfolding scenarios and controlled tests designed to elicit various affective states. The facial skin redness was measured from images extracted from the videos. Our observations revealed that hens exhibited the highest degree of facial skin redness in negative situations of high arousal, a high redness in positive situations of high arousal, and the lowest in positive situations of low arousal. In a second study, we further examined whether facial skin redness and secretory immunoglobulin A (S-IgA) can serve as markers for the quality of the human-animal relationship. Two groups of hens, one habituated to humans (n=13) and one non-habituated (n=12), were compared for general fearfulness in an open field test and for fear of humans in a reactivity to human test. In the open-field test, there were no statistical differences in general fearfulness, facial skin redness or S-IgA concentrations between both groups. However, habituated hens exhibited significantly lower fearfulness and facial skin redness in the presence of humans compared to non-habituated hens in the reactivity to human test. Additionally, habituated hens showed significant lower S-IgA concentration in lachrymal fluid in the presence of humans, with no significant differences in saliva or cloacal samples. We propose that changes in facial skin redness reflect variations in affective states and can be used as a marker for assessing the quality of the human-hen relationship. The relationship between S-IgA concentrations and affective states requires further investigation
Inactivation of Proprotein Convertases in T Cells Inhibits PD-1 Expression and Creates a Favorable Immune Microenvironment in Colorectal Cancer
International audienc