Changes in social environment induce higher emotional disturbances than changes in physical environment in quail

In intensive rearing, birds are exposed to frequent changes in both their social and physical environments, and this can have an impact on animal welfare under commercial conditions. The aim of the present study was to compare the emotional responses induced by social and non-social changes and to study the influence of the familiarity on these responses. Twenty-two female quail were first reared with a ball in 15–20-individual groups for 3 weeks from hatching. Then, each experimental subject was allocated either a familiar congener (CONG) or a familiar object (BALL). At 6 weeks of age the birds were fitted with a telemetric device to collect motor and cardiac activities. After that, each subject was exposed first to a separation from its cage-mate/familiar object, and secondly to the (re-)introduction of either the cage-mate/familiar object or of an unknown conspecific/another ball. Emotional responses were assessed through behavioural reactions and heart rate variability. Before being separated, both BALL and CONG quail showed stereotyped pacing that was more pronounced in BALL quail. BALL quail were not affected by the ball withdrawal, unlike CONG quail which reacted to the separation from their cage-mate by reducing activity and exploratory behaviour (P < 0.05). After the re-introduction, BALL quail remained closer to their ball and CONG quail spent more time with “stretched necks” than before the separation (P < 0.05). Surprisingly, CONG quail showed less stereotyped pacing when their partner was removed and recovered the initial level of stereotyped behaviour when their cage-mate was re-introduced (P < 0.01). Likewise, CONG quail also recovered the initial values of heart rate after the re-introduction of their cage-mate, indicating an increase in sympathetic activity compared to the isolation period. When the unfamiliar congener or ball was introduced in their cage, BALL quail pecked the unknown ball more than the familiar ball and had more contact with it (P < 0.05) and CONG quail had more contact with the unknown congener than with the cage-mate (P < 0.05). In conclusion, the quail appeared to experience a negative affective state before being separated, and there was no clear evidence of negative emotion in quail in response to the separation from either a social partner or an inanimate object. Nevertheless, the emotional responses of the quail in reaction to the (re-)introduction was influenced by the familiarity of the congener or the ball. Finally, changes in the quail's social environment induced more behavioural and cardiac modifications than changes in its non-social environment.

[1]  L. B. Murphy.  The practical problems of recognizing and measuring fear and exploration behaviour in the domestic fowl , 1978, Animal Behaviour.

[2]  L. Keeling,et al.  Social Behaviour in Farm Animals , 2001 .

[3]  A. D. Mills,et al.  The behavior of the japanese or domestic quail Coturnix japonica , 1997, Neuroscience & Biobehavioral Reviews.

[4]  J. Koolhaas,et al.  Different Sympathovagal Modulation of Heart Rate During Social and Nonsocial Stress Episodes in Wild-Type Rats , 1999, Physiology & Behavior.

[5]  A. Boissy,et al.  Emotional reactivity modulates autonomic responses to an acoustic challenge in quail , 2007, Physiology & Behavior.

[6]  R. C. Newberry,et al.  Breaking social bonds. , 2001 .

[7]  Linda J. Keeling,et al.  Spacing behaviour and an ethological approach to assessing optimum space allocations for groups of laying hens , 1995 .

[8]  Johan J. Bolhuis,et al.  MECHANISMS OF AVIAN IMPRINTING: A REVIEW , 1991, Biological reviews of the Cambridge Philosophical Society.

[9]  L. Désiré,et al.  On the way to assess emotions in animals: do lambs (Ovis aries) evaluate an event through its suddenness, novelty, or unpredictability? , 2004, Journal of comparative psychology.

[10]  L. Keeling,et al.  The social behaviour of domestic birds. , 2001 .

[11]  P. Timmermans,et al.  Do young guinea pigs (Cavia porcellus) develop an attachment to inanimate objects? , 1999, Behavioural Processes.

[12]  A. Boissy,et al.  Behavioral, Cardiac and Cortisol Responses to Brief Peer Separation and Reunion in Cattle , 1997, Physiology & Behavior.

[13]  I Veissier,et al.  Effect of autonomic blockers on heart period variability in calves: evaluation of the sympathovagal balance. , 2002, Physiological research.

[14]  J. Faure,et al.  Place preferences of Japanese quail given a permanent choice between a social or a non-social but enriched situation , 1998, Behavioural Processes.

[15]  R. B. Jones,et al.  Assessment of fear in adult laying hens: correlational analysis of methods and measures. , 1987, British poultry science.

[16]  L. Désiré,et al.  Emotions in farm animals: a new approach to animal welfare in applied ethology , 2002, Behavioural Processes.

[17]  Margo I. Wilson,et al.  An analysis of social interactions in Japanese quail, Coturnix coturnix japonica , 1972 .

[18]  H. Tsubone,et al.  Effects of psychological stress on autonomic control of heart in rats. , 2004, Experimental animals.

[19]  E. Rubel.  Effects of early experience on fear behaviour of Coturnix coturnix. , 1970, Animal behaviour.

[20]  L. Regolin,et al.  The development of responses to novel-coloured objects in male and female domestic chicks , 1994, Behavioural Processes.

[21]  A. D. Mills,et al.  Responses to isolation in Japanese quail genetically selected for high or low sociality , 1993, Physiology & Behavior.

[22]  A. D. Mills,et al.  Social discrimination in Japanese quail Coturnix japonica chicks genetically selected for low or high social reinstatement motivation , 1996, Behavioural Processes.

[23]  M. Hennessy,et al.  Factors influencing cortisol and behavioral responses to maternal separation in guinea pigs. , 1989, Behavioral neuroscience.

[24]  R. Jones,et al.  Responses of pair-housed male and female domestic chicks to the removal of a companion , 1992 .

[25]  Johan J Bolhuis,et al.  Early learning and the development of filial preferences in the chick , 1999, Behavioural Brain Research.

[26]  G. Breithardt,et al.  Heart rate variability: standards of measurement, physiological interpretation and clinical use. Task Force of the European Society of Cardiology and the North American Society of Pacing and Electrophysiology. , 1996 .

[27]  S. Gaioni,et al.  Distress calling induced by reductions in group size in ducklings reared with conspecifics or imprinting stimuli , 1982 .

[28]  E. Acevedo,et al.  Corticosterone response in the chick separation–stress paradigm , 2003, Physiology & Behavior.

[29]  L. Keeling,et al.  Assessment of positive emotions in animals to improve their welfare , 2007, Physiology & Behavior.

[30]  Armelle Prunier,et al.  Heart rate variability as a measure of autonomic regulation of cardiac activity for assessing stress and welfare in farm animals — A review , 2007, Physiology & Behavior.

[31]  J. Goldberger,et al.  Sympathovagal balance: how should we measure it? , 1999, The American journal of physiology.

[32]  Kevin B Freeman,et al.  Dissociation of stress behaviors in the chick social-separation-stress procedure , 2002, Physiology & Behavior.

[33]  Georgia Mason,et al.  Can't stop, won't stop: is stereotypy a reliable animal welfare indicator? , 2004 .

[34]  A. Malliani,et al.  Heart rate variability. Standards of measurement, physiological interpretation, and clinical use , 1996 .

[35]  A. Boissy,et al.  Genetic selection on a behavioural fear trait is associated with changes in heart rate variability in quail , 2007, Genes, brain, and behavior.