Demographic characterization and social patterns of the Neotropical pampas deer

Time budget seasonal variations in semi-captive pampas deer (Ozotoceros bezoarticus) females

The time and period of the day dedicated by several ruminant species to different activities (time budget) varies along the year. Pampas deer (Ozotoceros bezoarticus, Linnaeus, 1758) is an endangered species that lives in the southern cone of South America. Our aim was to describe seasonal variations of pampas deer female time budget under semi-captivity conditions. The study was performed at the Estación de Cría de Fauna Autóctona Cerro Pan de Azúcar (Uruguay), with 31 female' pampas deer housed in 6 breeding groups composed by 1 stag, 3-6 hinds and fawns. The behavior of each deer was recorded using instantaneous scan sampling every 15 m for approximately 8 h per day. On summer they spent more time lying and less time grazing (P < 0.0001); on winter, more time standing and eating ration (P < 0.0001), and on spring the time that they spent ruminating was maximum (P < 0.0001). At least in the conditions of this study, pampas deer females' time budget was strongly influenced by season.

Chemical profile of the cutaneous gland secretions from male pampas deer ( Ozotoceros bezoarticus )

Various cutaneous glands have been identified as sources of chemical signals that mediate many social interactions in deer. The pampas deer, a species considered near threatened, inhabits grasslands of South America. In this work, the chemical compositions from preorbital, tarsal, and digital gland secretions of semi-captive males were characterized by gas chromatography–mass spectrometry. The composition of these secretions showed a great complexity, with 143 compounds detected. Hierarchical cluster and principal component analyses show no relation to age or secretion type. Five compound classes (esters, fatty alcohols, lactones, sterols, and sulphuretted) differed with glands. The chemical complexity of the secretions, the individual differences in the whole compounds composition, and the absence of clustering by age lead to the hypothesis that these secretions may encode at once for individual information and for social status information.

Varias glándulas cutáneas han sido identificadas como productoras de señales químicas que median interacciones sociales en losciervos. El venado de las pampas es una especie considerada casi amenazada que habita los pastizales de Sudamérica. En este trabajo se caracterizó la composición química de las secreciones de las glándulas preorbital, tarsal e interdigital de machos por cromatografía de gases-espectrometría de masas. Estas secreciones mostraron una gran complejidad en su composición, con 143 compuestos detectados. No se observó ninguna agrupación de compuestos relacionada con la edad o el tipo de secreción. Cinco clases de compuestos (ésteres, alcoholes grasos, lactonas, esteroles, y compuestos azufrados) difirieron de acuerdo al origen glandular. La complejidad química de las secreciones, las diferencias individuales en dicha composición, y la ausencia de agrupamiento por edad, llevan a postular la hipótesis de que estas secreciones pueden codificar a la vez tanto información individual como del estado social.