title: The effect of a trapping procedure on the stress response of wild rainbow trout

authors: Clements, Shaun  P.

subjects: biology

abstract: Fish traps are a common research and management tool in which fish are subjected to procedures that elicit a stress response in other contexts. The effects of trapping on the stress response of sexually mature, wild rainbow trout Oncorhynchus mykiss were investigated during their upstream spawning migration by measuring concentrations of plasma cortisol, lactate, and glucose. Males had significantly lower basal plasma cortisol concentrations (6.1 ± 0.8 ng/mL [mean ± SE]) than females (21.4 ± 5.9 ng/mL). Similarly, the plasma cortisol response in males was significantly lower than that in females for all experiments. Fish working the barrier before entering the trap had increased concentrations of plasma cortisol. Confinement in the trap also induced a stress response. Plasma cortisol concentrations increased to 185.1 ± 40.9 ng/mL in males and 549.1 ± 60.1 ng/mL in females after confinement for 1 h. After processing, the magnitude of the stress response and the relative duration of recovery was less in fish that were confined longer in the trap. However, resting cortisol concentrations in females were not reached after 40 h of recovery in either group. Recovery to resting concentrations of plasma lactate occurred within 15 h after processing. In contrast, concentrations of plasma glucose remained significantly elevated at 40 h after processing. Postspawning fish had significantly lower plasma concentrations of cortisol, glucose, and lactate following application of an extreme stressor compared with prespawning fish. Based on the results of this study, we conclude that the trapping procedure induces a severe and prolonged stress response in wild rainbow trout.

text: The effect of a trapping procedure on the stress response of wild rainbow trout Fish traps are a common research and management tool in which fish are subjected to procedures that elicit a stress response in other contexts. The effects of trapping on the stress response of sexually mature, wild rainbow trout Oncorhynchus mykiss were investigated during their upstream spawning migration by measuring concentrations of plasma cortisol, lactate, and glucose. Males had significantly lower basal plasma cortisol concentrations (6.1 ± 0.8 ng/mL [mean ± SE]) than females (21.4 ± 5.9 ng/mL). Similarly, the plasma cortisol response in males was significantly lower than that in females for all experiments. Fish working the barrier before entering the trap had increased concentrations of plasma cortisol. Confinement in the trap also induced a stress response. Plasma cortisol concentrations increased to 185.1 ± 40.9 ng/mL in males and 549.1 ± 60.1 ng/mL in females after confinement for 1 h. After processing, the magnitude of the stress response and the relative duration of recovery was less in fish that were confined longer in the trap. However, resting cortisol concentrations in females were not reached after 40 h of recovery in either group. Recovery to resting concentrations of plasma lactate occurred within 15 h after processing. In contrast, concentrations of plasma glucose remained significantly elevated at 40 h after processing. Postspawning fish had significantly lower plasma concentrations of cortisol, glucose, and lactate following application of an extreme stressor compared with prespawning fish. Based on the results of this study, we conclude that the trapping procedure induces a severe and prolonged stress response in wild rainbow trout.

year: 2002

title: Towards a philosophy of academic publishing

authors: Peters, Michael A.

abstract: This article is concerned with developing a philosophical approach to a number of significant changes to academic publishing, and specifically the global journal knowledge system wrought by a range of new digital technologies that herald the third age of the journal as an electronic, interactive and mixed-media form of scientific communication. The paper emerges from an Editors' Collective, a small New Zealand-based organisation comprised of editors and reviewers of academic journals mostly in the fields of education and philosophy. The paper is the result of a collective writing process.

text: Towards a philosophy of academic publishing This article is concerned with developing a philosophical approach to a number of significant changes to academic publishing, and specifically the global journal knowledge system wrought by a range of new digital technologies that herald the third age of the journal as an electronic, interactive and mixed-media form of scientific communication. The paper emerges from an Editors' Collective, a small New Zealand-based organisation comprised of editors and reviewers of academic journals mostly in the fields of education and philosophy. The paper is the result of a collective writing process.

year: 2016

title: Understanding ‘higher’ Māori fertility in a ‘low’ fertility context: Does cultural identity make a difference?

authors: Rarere, Moana

subjects: Maori fertility

abstract: The Māori fertility transition brought an end to decades of very high fertility rates, and a convergence towards long-term fertility levels similar to Pākehā/New Zealand European women. However, important differences endure. The Māori total fertility rate (TFR) remains above replacement level, and Māori women have children earlier and over a longer period. All of this has and still is occurring in a society that facilitates and favours low fertility and small family sizes. Using births data and cultural identity markers in the New Zealand Census, this paper explores the influence of culture as a contributing factor to higher fertility outcomes amongst Māori women in a low-fertility society.

text: Understanding ‘higher’ Māori fertility in a ‘low’ fertility context: Does cultural identity make a difference? The Māori fertility transition brought an end to decades of very high fertility rates, and a convergence towards long-term fertility levels similar to Pākehā/New Zealand European women. However, important differences endure. The Māori total fertility rate (TFR) remains above replacement level, and Māori women have children earlier and over a longer period. All of this has and still is occurring in a society that facilitates and favours low fertility and small family sizes. Using births data and cultural identity markers in the New Zealand Census, this paper explores the influence of culture as a contributing factor to higher fertility outcomes amongst Māori women in a low-fertility society.

year: 2018