Testosterone profiles and semen characteristics were determined using yearling and adult captive wild-strain Mallard (Anas platyrhynchos) drakes. Wild-strain Mallard hens were artificially inseminated by modifying a technique developed for domesticated poultry. In both adult and yearling drakes, there was a change in the concentration of circulating plasma testosterone during the reproductive s...

Fertility control has gained considerable momentum as a management tool to regulate populations of captive and wild animals and to control aggressive behaviour or improve meat quality in livestock. Anti-fertility vaccination (immunocontraception and immunocastration) is a humane alternative to methods that rely on surgical or chemical sterilisation and lethal control. Two types of experimental ...

—Many effects of diseases on cultured fish are known; they are less clear in wild fish populations. Cultured fish represent captive populations that can be subjected to intense scrutiny with an increasing range of diverse and powerful tools. Disease represents a spectrum from acute mortality to rather benign or inconsequential syndromes, all sharing the common feature of a deviation from the no...

In late summer 2006 considerable mortality in wild and captive Passeriformes and Strigiformes was observed in Zurich, Switzerland. All animals were found in a range of 2 km(2). Observed clinical signs involved depression, ruffled plumage, incoordination, seizures and peracute death. Nutritional status was generally moderate to poor in wild birds, and variable in captive animals. Necropsy showed...

Bears consuming wild fruits for fall energy accumulation are constrained by several factors, including intake rate, the physiological capacity of the gastrointestinal tract, and the metabolic efficiency of gain in body mass. We measured these relationships through foraging and feeding trials using captive and wild black bears (Ursus americanus) and grizzly bears (Ursus arctos). Four fruit types...

Abstract In recent years lion bones have been legally traded internationally to Asian markets from captive-bred sources in South Africa. There are also indications of increasing instances illegal international trade wild bones. The existence parallel captive and supplies bone a cause law enforcement concern regarding the potential for laundering illegally sourced through legal trade, present pr...

The stress response of wild and captive reared rainbowfish (Melanoteania duboulayi) following chasing by a simulated predator was examined. Cortisol release rate was monitored using a flow through system by measuring water borne hormone levels. Tests using known cortisol concentrations revealed that the technique yielded 95% of the cortisol present in the water. Cortisol release rates increased...

First posted June 8, 2023 For additional information, contact: Director, Forest and Rangeland Ecosystem Science Center777 NW 9th Street Suite 400Corvallis, OR 97330 Captive breeding release programs have been instrumental in preventing the extinction of some wildlife species, but these less successful for other species. Evaluating initial guidelines procedures to start a captive program particu...