No abstract

1983. Determining matrilineal kinship in natural populations of rodents using radionuclides. Can. J. Zool. 61: 27 1-274. We have developed a technique that can accurately determine mother-offspring relatedness of voles in the field. Trapped pregnant females are injected with one or more gamma-emitting radionuclides and then released. The isotope concentration, while very low, is sufficiently high that young, when subsequently captured and counted in a very sensitive whole-body gamma spectroscope, can be clearly identified by the spectral characteristics of the nuclides used to tag the mother. Both laboratory and field studies have demonstrated that the eight nuclides used to date reach the developing fetuses across the placental barrier and the neonates via the mother's milk. The radionuclide technique has potential widespread application in the fields of ecology, population biology, and sociobiology. TAMARIN, R. H., M. SHERIDAN et C. K. LEVY. 1983. Determining matrilineal kinship in natural populations of rodents using radionuclides. Can. J. Zool. 61: 27 1-274.On trouvera ici la description d'une technique permettant de determiner en nature les relations mere-petit chez des campagnols: des femelles gravides prises au piege re~oivent des injections d'un ou plusieur radionucleides emetteurs de rayons gamma avant d'gtre relichees. Les jeunes sont ensuite captures et analyses dans un spectroscope a radiations gamma tres sensible et capable de contenir I'animal entier; la concentration d'isotopes, bien que minime, permet d'identifier les petits d'apres les caracteristiques spectrales des nucleides qui ont servi a marquer la mere. En laboratoire et en nature, les huit nucleides utilises jusqu'a maintenant traversent le placenta et atteignent le fetus en croissance ou alors rejoignent le nouveau-ne par le lait maternel. Les radionucleides semblent appeles a jouer un r81e considerable en ecologie, en dCm6cologie et en sociobiologie.[Traduit par le journal]

Gamma‐emitting radionuclides were used in single and double‐isotope combinations to label individual colonies of the subterranean termite Reticulitermes flavipes Kol. Each of these radionuclides produces a characteristic and identifiable energy spectrum upon decay, and using whole‐body gamma spectroscopy, the characteristic spectral emission ‘signatures’ of each isotope and their relative quantities were detected in workers, brachypterous nymphs, and alates. Radionuclides present in a food source were rapidly incorporated into workers, and reached detection limits within one to three days. Isotopic labels were transferable between colony members, and all individuals in laboratory colonies were labeled within 21 days of initial contact with foragers that had fed at a labeled food source. Single‐ and double‐label nuclide markers were transferred to sexual forms (prealates and alates) by social food flow. Applications of radionuclide labeling and gamma spectroscopic analysis in insect behavioral ecology are discussed. RÉSUMÉ Marquage iso topique de colonies d'insectes sociaux: les radionucléides γ comme marqueurs individuels Des radionucléides γ ont été utilisés seuls ou en combinaison par 2 pour marquer des individus de colonies de Reticulitermes flavipes. Chaque radionucléide possède ses caractères spectraux. Avec un spectroscope γ très sensible, pouvant contenir l'insecte entier, il est possible d'identifier les ‘signatures’ spectrales de chaque isotope et les quantités relatives de chacun d'eux chez les ouvriers, les larves brachyptères et les ailés. Les radionucléides présents dans le papier consommé sont rapidement incorporés chez les ouvriers, et atteignent le seuil de détection en 1 à 3 jours. Le marquage isotopique se transmet entre les membres de la colonie; tous les habitants de colonies de laboratoire ont été contaminés en 21 jours, après des contacts avec des individus alimentés sur une source marquée. Les marqueurs isotopiques avec 1 ou 2 radionucléides sont transférés aux sexués par les échanges trophallaxiques. La discussion porte sur les applications du marquage aux radionucléides et l'analyse au spectroscope γ en écologie éthologique des insectes.

In unanesthetized dogs, adrenal venous blood was collected and its plasma content of 17-hydroxycorticosteroids (17-OHCS) estimated. Electrodes were implanted in the brain stem and electrical stimulation was performed. The location of the electrode tips was verified histologically. After stimulation of the lower posterior hypothalamic area, as well as the lower thalamic area, the adrenal 17-OHCS secretion rate increased markedly. When the upper posterior hypothalamic area, or the area preoptica was stimulated, the slight increase in 17-OHCS secretion rate first observed was followed by a marked decrease below the prestimulation level. Stimulation of the capsula interna produced no response in adrenal cortical secretion.

A major obstacle limiting field studies in plant population biology is that there is no way of uniquely labeling or identifying the seeds produced by a mother plant so that her seedlings can be distinguished from the offspring of other conspecific plants. This article describes experiments undertaken to develop gamma—emitting radionuclide labels that are injected into a plant and are incorporated into the developing seeds and subsequent seedlings. The nuclides were used singly and in combination since each nuclide has unique spectral peaks that can be used to distinguish it from other nuclides. Five species were used: Phaseolus vulgaris, Polygonum pensylvanicum, Impatiens capensis, Bidens frondosa, and B. connata. Easily detectable levels of 58cobalt, 60cobalt, 134cesium, 137cesium, and 75selenium were incorporated by seeds of the five species. The incorporation of 54manganese and 65zinc varied among the species. 88Yttrium, 125antimony, and 85strontium were weak or not present as labels, depending on the species, while 110silver and 46scandium were never found in the seeds. Bean seedlings showed readily detectable amounts of nuclide label, while the nuclides apparently leached out of the Impatiens seedlings. The quantities of nuclides used in these experiments were so low that there was no effect of radiation on plant performance.