Pain and husbandry practices, from theory to experimental applications : examples of AGRI animal welfare network actions

In agreement with the European movement towards recognition of animal sensitivity, a group of INRA scientists, from complementary fields, have focused their work on the issue of pain associated with certain farming practices. After a step devoted to define the concepts of sensitivity, nociception, pain and suffering, several practices were selected: castration, teeth clipping and tail docking in piglets, force feeding in Mulard ducks, and feeding practices designed to increase milk yields in small ruminants (goats). Various functional indices and behavioural signs, known for their association with stress, pain or inflammation, were studied. The data include endocrine parameters (cortisol or corticosterone, ACTH), glucose or lactate levels, a neuro-vegetative index such as the heart rate, neurogenic plasma extravasation, evidence of local inflammation, which can be demonstrated with a marker such as circulating haptoglobin. Behavioural signs associated with different practices were systematically analysed. This approach leads to the creation of a new field of research and to the accumulation of knowledge in order to i) understand the genesis of nociceptive signals of somesthetic or visceral origin, and ii) evaluate sensory or emotional experiences associated with such practices. Our data show that some husbandry practices that were studied generate pain and inflammatory responses.Dans le contexte européen d'une reconnaissance de la sensibilité des animaux, des chercheurs de l'INRA, issus de disciplines complémentaires, ont uni leurs efforts pour travailler sur la question de la douleur associée à certaines pratiques d'élevage. Les travaux ont été engagés après une réflexion approfondie sur les notions de sensibilité, nociception, douleur et souffrance. Plusieurs pratiques ont été sélectionnées : castration, épointage des dents et caudectomie du porcelet, gavage du canard Mulard, conduite alimentaire visant de hauts rendements laitiers chez le petit ruminant (chèvre). Divers index fonctionnels et signes comportementaux, connus pour leur association avec le stress, la douleur ou l'inflammation ont été étudiés. Les données concernent des paramètres endocriniens (cortisol ou corticostérone, ACTH), les taux de glucose ou de lactate, un indice neurovégétatif comme le rythme cardiaque, la réaction neurogène d'extravasation plasmatique qui se manifeste, au niveau local, par une inflammation, et dont la présence peut être validée par un marqueur tel que l'haptoglobine circulante. Les manifestations comportementales associées aux différentes pratiques sont systématiquement analysées. Cette démarche aboutit à construire un champ de recherche et de connaissances permettant i) de comprendre la genèse de signaux nociceptifs d'origine somesthésique ou viscérale, ii) d'évaluer le «vécu sensoriel ou émotionnel » associé à ces pratiques. Nos données permettent d'identifier que certains actes sont générateurs de douleur et associés au déclenchement d'un processus inflammatoire

Consequences of low electrical currents on the welfare of dairy cattle. Emphasis on individual variability

When heifers were exposed to an electrical current which voltage was increased daily, a short-term persistent reaction threshold of 2.3 V (3.5 mA) was observed, despite a large individual variability. In the medium-term, a multi-criteria experimental approach in dairy cows exposed to a permanent (predictable) or random (unpredictable) voltage of 1.8 V (3.6 mA) on the water trough showed no modification of the amount and composition of milk, although a transient acute stress response was observed. Cows exposed permanently to the voltage became habituated to it, whereas those exposed unpredictably may have shown signs of a mild chronic stress. The individual variability of the cow resistance could explain the differences in behavioural responses. In farms, it is important to reduce the presence of stray voltage, even of low level, as they may affect animal welfare.Lors de l’application d’une tension électrique augmentée progressivement chaque jour, un seuil de réaction persistante de 2,3 V (3,5 mA) a été mis en évidence à court terme chez des génisses, malgré une forte variabilité individuelle. À moyen terme, une analyse multicritère a montré que l’exposition de vaches laitières, de manière permanente (prévisible) ou aléatoire (imprévisible), à une tension de 1,8 V (3,6 mA) au niveau de l’abreuvoir n’a pas modifié la quantité de lait produite ni sa composition, bien qu’une réponse de stress aigu transitoire ait été observée. Les vaches exposées de manière permanente se sont habituées, contrairement aux vaches exposées de manière imprévisible chez lesquelles la présence d’un stress chronique modéré est envisagée. La variabilité individuelle de résistance des vaches pourrait expliquer la variabilité des réponses comportementales. En élevage, il est important de limiter la présence de tensions parasites, même de faible niveau, qui pourraient perturber le bien-être des animaux

Face-based perception of emotions in dairy goats

Faces of conspecifics convey information about identity, but also gaze, and attentional or emotional state. As a cognitive process, face-based emotion recognition can be subject to judgment bias. In this study we investigated whether dairy goats (n = 32) would show different responses to 2-D images of faces of familiar conspecifics displaying positive or negative emotional states. We also examined the possible use of images of faces as stimuli in cognitive bias studies. The faces of four subjects were photographed in a positive and a negative situation. Three types of images of ambiguous facial expressions were then created using morphing software (75% positive, 50% positive, and 25% positive). In a test-pen, each goat was exposed for 3 seconds to each type of image, obtained from the same goat. All goats were shown non-morphed faces first, before being shown the three types of morphed faces, balanced for order. Finally, the first non-morphed face was shown again. Spontaneous behavioural reactions including ear postures (forward, backward and asymmetrical) and interactions with the screen (time spent looking or touching) were recorded during the 3 seconds. Results were analysed using REML with repeated measurements. Goats spent more time with their ears forward when the negative was shown compared to the positive(F4,121.3 = 2.51, P = 0.018), indicating greater interest in negative faces. Identity of the photographed goat influenced the time spent with the ears forward (F2,57.4 = 7.01, P = 0.002). We conclude that goats react differently to images of faces displaying different emotional states and that they seem to perceive the emotional valence expressed in these images. Response to morphed faces was not necessarily intermediate to response to negative and positive faces, and not on a continuum. Further study is thus needed to clarify the potential use of faces in cognitive bias studies

Peut-on évaluer le stress chronique en dosant le cortisol dans le poil des chèvres ?

Les animaux d’élevage peuvent être confrontés à des situations stressantes pouvant impacter leur bien-être. Chez l’homme, le cortisol des cheveux pourrait être un bon indicateur du stress chronique (Yamada et al., 2007). Nous avons cherché à mettre au point une méthode d’évaluation non invasive du stress chez la chèvre par dosage du cortisol dans le poil après simulation de stress chronique par injections d’ACTH

Mortality of young animals: the scale of the problem

International audienc

Kick-starting ovarian cyclicity by using dietary glucogenic precursors in post-partum dairy cows: a review

International audienceThe objective of this review is to describe how dietary glucogenic precursors could stimulate ovarian activity in post-partum dairy cows and improve reproductive success. Although the nutrient requirements for the early resumption of ovarian cycles, and for follicle and embryo development are quantitatively small, reproductive success is deteriorated by post-partum negative energy balance. Since very little glucose is absorbed directly from the digestive tract of ruminants one of the targets for nutritional manipulation could be the glucogenic potential of the diet. This could be achieved by giving rumen-resistant starch or mono-propylene glycol. Both these adaptations increase glucose, insulin and insulin-like growth factor-1 plasma concentrations and stimulate ovarian follicle growth

Mortality of young animals: the scale of the problem

International audienc

Mortality of young animals: the scale of the problem

International audienc

Milk urea: a promising non-invasive indicator of SARA in dairy goats in the context of PLF?

International audienc