Reproductive and Stress Response Hormones of the Critically Endangered Southern Muriqui (Brachyteles arachnoides: Atelidae) Under Captive Conditions

International Journal of Primatology - The Convention on Biological Diversity and the International Union for Conservation of Nature emphasize that ex situ conservation efforts are unavoidable....     

Monoarticular antigen-induced arthritis leads to pronounced bilateral upregulation of the expression of neurokinin 1 and bradykinin 2 receptors in dorsal root ganglion neurons of rats

This study describes the upregulation of neurokinin 1 and bradykinin 2 receptors in dorsal root ganglion (DRG) neurons in the course of antigen-induced arthritis (AIA) in the rat knee. In the acute phase of AIA, which was characterized by pronounced hyperalgesia, there was a substantial bilateral increase in the proportion of lumbar DRG neurons that express neurokinin 1 receptors (activated by substance P) and bradykinin 2 receptors. In the chronic phase the upregulation of bradykinin 2 receptors persisted on the side of inflammation. The increase in the receptor expression is relevant for the generation of acute and chronic inflammatory pain.     

Physiological and behavioral indices of short-term stress in wild vicuñas (Vicugna vicugna) in Jujuy Province,Argentina

The management of wild vicuñas can trigger a stress response that may compromise welfare. In Santa Catalina, Jujuy Province, Argentina, indices of short-term stress associated with capture, handling, and shearing were studied in 105 wild vicuñas (Vicugna vicugna). The study included 2 groups (n = 59 and n = 46) of wild vicuñas captured in 2 consecutive days. Independent variables analyzed included sex, restraint time, and groups. Cortisol, creatine kinase, glucose, white blood cells, temperature, heart rate, and respiratory frequency were higher than published values. Respiratory rate increased during handling and correlated with holding time and group size, while heart rate decreased. Packed cell volume was higher in females. Cortisol concentrations differed between restraint groups and sex and inversely correlated with agonistic behavior. The most common behavior was increased vigilance. Sternal recumbency increased over holding time. During handling procedures, frequency of sudden movements like kicking and attempts to stand increased as restraint time increased. Females vocalized more than males. In conclusion, the methods used triggered measurable changes suggestive of short-term stress that appeared to be physiologically tolerated by the vicuñas.     

Development of a Differential Set for the Race analysis of Puccinia hordei Otth.

Investigations for the race analysis of P. hordei (location Cologne, W.-Germany) showed, that most of the resistant genotypes in the International differential set with Pa₁ to Pa₈ were ineffective for that purpose. Out of 80 selected barley genotypes with different degree of resistance against the field-collection RG 1975 hosts with a strongly differentiating effect were chosen. This was done using three parameters: mean resistance x?w, its standard deviation x?w and the range z. They were calculated from evaluating the reaction types of 80 barley genotypes infected with 116 single-pustule lines of barley brown rust. Eight hosts with strongly differentiating reactions towards the 116 rust lines were composed into a differential set, which could characterize the heterogeneity of the Cologne P. hordei-population essentially better and more precisely than the International differential set.     

Social influences on estrogen excretion and ovarian cyclicity in saddle back tamarins (Saguinus fuscicollis)

The effects of different social living conditions on estrogen excretion and on the ovarian cycle of saddle back tamarins were investigated. Urinary estrogens were monitored as indices of ovarian cyclicity in groups of adult females living under the following experimental conditions: (1) five parous females, each living with an adult castrated male (in one of the females plasma estradiol and progesterone were also measured); (2) five adult daughters living with their families. Each daughter was then removed from her family and paired with a vasectomized male. After pairing, scent marks collected from the family were introduced daily to one of the daughters and her mate. Scent exposure was then discontinued and hormone excretion measured for several weeks. The remaining four daughters were not exposed to family scent. The females living with castrated males showed urinary estrogen cycles of an average length of 17.5 ± 1.0 days. The plasma estrogen cycle was of the same length. The females studied under condition 2 showed low, noncycling estrogen levels while living in their families. They responded to pairing with an increase in the level of urinary estrogens, and four out of five showed regular estrogen cyclicity. The fifth female exposed to family scent marks after pairing also showed an increase in urinary estrogens. However, as long as scent transfer was maintained, no cycle was observed. Estrogen excretion increased again, and cyclicity commenced when scent transfer was discontinued. It is concluded that ovarian estrogen production is suppressed and cyclicity does not occur as long as daughters live in their families. Release from suppression and perhaps stimulation by the male cause a rapid increase in estrogen levels and the onset of cyclicity. Chemical stimuli produced by the family, perhaps particularly by the mother, may be involved in reproductive suppression.     

Die Beeinflussung der Histochemisch Nachweisbaren ATPase-Aktivität unter verschiedenen Versuchsbedingungen beim Vergleich der Ca- sowie Pb-Methode bei Ph 7,5 bzw. 7,2

Zusammenfassung Es wird über vergleichende Untersuchungen beim Nachweis der ATPase im niederen pH-Bereich unter Verwendung der Ca- und Pb-Methode berichtet. Hierbei zeigt es sich, daß es sich um ATPasen mit unterschiedlichen Eigenschaften handelt. Während die ATPase pH 7,2 keine Abhängigkeit von SH-Gruppen aufweist und Mg^.. benötigt, wird die Aktivität der ATPase pH 7,5 (Ca-Methode) durch SH-Gruppen-Blocker gehemmt, es tritt eine Aktivitätsminderung nach Zugabe von Mg^.. ins Inkubationsmedium ein. Auch der Einfluß der Fixierung ist bei beiden ATPasen unterschiedlich. Unabhängig hiervon ist hervorzuheben, daß sich auch Unterschiede im Verhalten der ATPase in Abhängigkeit vom untersuchten Organ ergeben. Unsere Ergebnisse unterstützen die Notwendigkeit eines spezifischen, von der Fragestellung bestimmten, Nachweises der ATPase.

---

Summary The results of comparative studies on the determination of ATP-ase in the low pH range (using the Ca- and the Pb-method) are reported. The findings show that there are ATP-ases of different properties. Whereas ATP-ase pH 7.2 depends not on SH-groups but on the presence of Mg^.., the activity of ATP-ase pH 7.5 (Ca-method) is inhibited not only by SH-group blockers but also by the addition of Mg^.. to the incubation medium. There is also evidence that fixation has varying effects on ATP-ases. However, it must be emphasized that there are differences in the ATP-ase activity within the various organs investigated. Our results show that the choice of the method for a specific demonstration of ATP-ase depends to a very high degree on the problem under investigation.

     

Environmental heterogeneity determines the ecological processes that govern bacterial metacommunity assembly in a floodplain river system

How diversity is structured has been a central goal of microbial ecology. In freshwater ecosystems, selection has been found to be the main driver shaping bacterial communities. However, its relative importance compared with other processes (dispersal, drift, diversification) may depend on spatial heterogeneity and the dispersal rates within a metacommunity. Still, a decrease in the role of selection is expected with increasing dispersal homogenization. Here, we investigate the main ecological processes modulating bacterial assembly in contrasting scenarios of environmental heterogeneity. We carried out a spatiotemporal survey in the floodplain system of the Paraná River. The bacterioplankton metacommunity was studied using both statistical inferences based on phylogenetic and taxa turnover as well as co-occurrence networks. We found that selection was the main process determining community assembly even at both extremes of environmental heterogeneity and homogeneity, challenging the general view that the strength of selection is weakened due to dispersal homogenization. The ecological processes acting on the community also determined the connectedness of bacterial networks associations. Heterogeneous selection promoted more interconnected networks increasing β-diversity. Finally, spatiotemporal heterogeneity was an important factor determining the number and identity of the most highly connected taxa in the system. Integrating all these empirical evidences, we propose a new conceptual model that elucidates how the environmental heterogeneity determines the action of the ecological processes shaping the bacterial metacommunity.Subject terms: Community ecology, Microbial ecology