TY - JOUR

T1 - Indicators of age, body size and sex in goat kid calls revealed using the source-filter theory

AU - Briefer, Elodie

AU - McElligott, Alan G.

N1 - Funding Information: We are grateful to E. Antill, C. Booth, E. Cant, C. Charpin, K. Cho Geun-A, C. Farrington, F. Galbraith, L. Kashap, J. Kemp, E. Landy, M. Padilla de la Torre and M. Wang for assistance, and to two anonymous referees for helpful comments on the manuscript. We thank D. Reby for providing the custom built program in Praat. E. Briefer is funded by a Swiss National Science Foundation fellowship. We acknowledge the financial support of the University of London Central Research Fund . We thank the staff of White Post Farm ( http://whitepostfarmcentre.co.uk/ ) for their help and free access to the animals.

PY - 2011

Y1 - 2011

N2 - The source-filter theory is an important framework recently applied to the study of animal vocalisations, which links the mode of vocal production to call parameters. Vocalisations can be good indicators of a sender's characteristics, such as identity, body size, age, and even hormonal status and affective states. For these reasons, applied vocal communication research would greatly benefit from adopting the source-filter theory approach to identify key call parameters linked to physical and physiological characteristics of domestic animals. Here, we introduce the source-filter theory through a detailed analysis and interpretation of goat contact calls during development. In mammals, vocal development is mostly influenced by maturation. Maturational processes of vocalisations are linked to growth or sex hormone effects on the larynx and vocal tract. We investigated changes to the parameters of goat contact calls during ontogeny, according to age, body size and sex. We recorded goat kids from birth to four months old and analysed their calls by considering the shape and functioning of the vocal apparatus. We found age and sex-related changes to most of the measured vocal parameters, suggesting a direct or indirect effect of sex hormones on vocal ontogeny. Furthermore, body size growth was negatively correlated with most frequency parameters, indicating that vocal production is constrained by body size throughout development. Therefore kid vocalisations provide information about age, sex and body size. We suggest that similar analyses applied to the study of vocal correlates of affective states, could greatly help the discovery of convenient and non-invasive indicators of animal welfare.

AB - The source-filter theory is an important framework recently applied to the study of animal vocalisations, which links the mode of vocal production to call parameters. Vocalisations can be good indicators of a sender's characteristics, such as identity, body size, age, and even hormonal status and affective states. For these reasons, applied vocal communication research would greatly benefit from adopting the source-filter theory approach to identify key call parameters linked to physical and physiological characteristics of domestic animals. Here, we introduce the source-filter theory through a detailed analysis and interpretation of goat contact calls during development. In mammals, vocal development is mostly influenced by maturation. Maturational processes of vocalisations are linked to growth or sex hormone effects on the larynx and vocal tract. We investigated changes to the parameters of goat contact calls during ontogeny, according to age, body size and sex. We recorded goat kids from birth to four months old and analysed their calls by considering the shape and functioning of the vocal apparatus. We found age and sex-related changes to most of the measured vocal parameters, suggesting a direct or indirect effect of sex hormones on vocal ontogeny. Furthermore, body size growth was negatively correlated with most frequency parameters, indicating that vocal production is constrained by body size throughout development. Therefore kid vocalisations provide information about age, sex and body size. We suggest that similar analyses applied to the study of vocal correlates of affective states, could greatly help the discovery of convenient and non-invasive indicators of animal welfare.

KW - Acoustic analysis

KW - Capra hircus

KW - Ungulate

KW - Vocal communication

KW - Vocal development

U2 - 10.1016/j.applanim.2011.05.012

DO - 10.1016/j.applanim.2011.05.012

M3 - Journal article

AN - SCOPUS:79960278313

VL - 133

SP - 175

EP - 185

JO - Applied Animal Behaviour Science

JF - Applied Animal Behaviour Science

SN - 0168-1591

IS - 3-4

ER -