Offspring grazing and suckling rates in a sexually dimorphic ungulate withbiased maternal investment (Ammotragus lervia)

Authors
Citation
J. Cassinello, Offspring grazing and suckling rates in a sexually dimorphic ungulate withbiased maternal investment (Ammotragus lervia), ETHOLOGY, 107(2), 2001, pp. 173-182
Citations number
29
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Animal Sciences","Neurosciences & Behavoir
Journal title
ETHOLOGY
ISSN journal
0179-1613 → ACNP
Volume
107
Issue
2
Year of publication
2001
Pages
173 - 182
Database
ISI
SICI code
0179-1613(200102)107:2<173:OGASRI>2.0.ZU;2-C
Abstract
An analysis of resource gain is provided for Ammotragus calves during their first year of age. Both grazing and suckling rates are analysed and potent ial effects caused by age, sex, mother's rank and weaning period studied. D uring their first day of life, calves devote their time mainly to suckling, grazing starting at the second week of age and exceeding suckling rate fro m the fourth week onwards. When suckling rate reaches a significant decreas e (at 2 mo), male calves show a significantly higher grazing rate than fema le calves, suggesting a higher energetic demand for males at this age. When calves are 1 mo old, sons of high-ranking mothers devote less time grazing than those of low-ranking ones, which is in accordance with the higher mat ernal investment they receive. Crazing rate shows distinctive values for th e different weaning periods distinguished in this species, but the resumpti on of mothers' sexual activity, when a mother-offspring conflict occurs, do es not affect grazing behaviour. These results are consistent with the bias ed maternal investment recently found in the same study population but focu sing on another aspect, i.e. grazing behaviour, which is determined by calv es' own decisions.