From Hatchling to Adulthood: Exploring the Effects of Developmental Temperature on Mitochondrial Function in Japanese quail (Coturnix japonica)
(2023) BION03 20221Degree Projects in Biology
- Abstract
- Extreme weather events, such as heatwaves and cold spells, are predicted to increase under climate change, which can have significant negative effects on fitness and survival of wildlife. If such variations are timed during development, they can affect growth and subsequent performance in birds, with influence over long-term temperature tolerance. Developmental temperature can also have direct effects on the ontogeny of the metabolic machinery, including on mitochondrial function, but it is not well understood how this might influence growth and maturation. Since mitochondria produce most of the energy used by the organism (in the form of adenosine triphosphate, ATP), studying how these organelles respond to thermal variations can provide... (More)
- Extreme weather events, such as heatwaves and cold spells, are predicted to increase under climate change, which can have significant negative effects on fitness and survival of wildlife. If such variations are timed during development, they can affect growth and subsequent performance in birds, with influence over long-term temperature tolerance. Developmental temperature can also have direct effects on the ontogeny of the metabolic machinery, including on mitochondrial function, but it is not well understood how this might influence growth and maturation. Since mitochondria produce most of the energy used by the organism (in the form of adenosine triphosphate, ATP), studying how these organelles respond to thermal variations can provide insight into the cellular mechanism underlying key processes such as growth and thermoregulatory capacity, and how these might differ between life-stages. To investigate this, Japanese quail were raised in warm and cold temperatures, from hatching until adulthood, and mitochondrial function was measured in blood cells at key developmental time points. After sexual maturity, half of the birds from each group were placed in a common garden at an intermediate temperature to test whether changes to the mitochondrial phenotype were plastic or programmed by early-life thermal conditions. Overall, there was an increase in mitochondrial metabolism from hatching until 20 weeks (i.e., at the end of the study) in all treatments. Mitochondrial coupling efficiency was the most efficient during early developmental stages at 3 weeks, although it did not differ afterwards. Individuals raised in the warm treatment had a lower baseline and ATP-producing respiration compared to those exposed to cold temperatures. Birds moved to the common garden largely maintained their phenotypic responses to their developmental temperature, indicating long-lasting effects to long-term exposure of suboptimal temperatures. Variation between the sexes was also detected, as females had higher mitochondrial efficiency compared to males in all treatments, even when moved to a different thermal environment. Adult males exposed to cold temperatures during development showed decrease in reserve capacity, in contrary to those reared in warmer temperatures. This study can provide insight into how mitochondrial metabolism develops in birds and how it can be impacted by immediate climate change effects, such as extreme weather events, by evaluating contrasts throughout different life-stages. (Less)
- Popular Abstract
- Developmental temperature effects on mitochondrial function
Extreme weather events, such as heatwaves and cold spells, are predicted to increase under climate change. Adverse temperatures during development may affect growth and performance of animals and also affect the function of mitochondria, which are organelles responsible for producing most of the energy used by the organism. Investigating how mitochondria respond to temperature can therefore provide insight into the mechanisms responsible for growth and thermoregulatory capacity. The impact of extreme weather events on the cellular level and how these vary throughout various life-stages can be helpful for wildlife conservation, in determining population fitness, optimal habitats... (More) - Developmental temperature effects on mitochondrial function
Extreme weather events, such as heatwaves and cold spells, are predicted to increase under climate change. Adverse temperatures during development may affect growth and performance of animals and also affect the function of mitochondria, which are organelles responsible for producing most of the energy used by the organism. Investigating how mitochondria respond to temperature can therefore provide insight into the mechanisms responsible for growth and thermoregulatory capacity. The impact of extreme weather events on the cellular level and how these vary throughout various life-stages can be helpful for wildlife conservation, in determining population fitness, optimal habitats and stressor levels for animals.
To investigate this, Japanese quail (Coturnix japonica) were raised in two different temperatures – warm (30 °C) and cold (10 °C) – from hatching until adulthood. Mitochondrial function was measured through small volumes of blood at several key developmental time points: 3, 8, 12 and 20 weeks post-hatching. After 9 weeks, half of the birds from each treatment were moved to a common environment (20 °C) to verify if responses to cold and warm temperatures remain in adulthood at an optimal temperature.
From hatchling to adulthood: variations across life-stages
Overall, there was an increase in mitochondrial respiration from hatching until 20 weeks in both temperatures. Mitochondrial efficiency, the efficiency in which the oxygen consumed by the mitochondria is used to drive the production of energy, was higher at 3 weeks when birds were halfway to adulthood, although it did not differ afterwards. As there was no significant difference in body mass gain from hatchling until adulthood between temperatures, these results suggest that there was no compromise between development and the ability to sustain body temperature at early ages. Individuals raised at cold temperatures had a higher oxygen consumption linked to energy production compared to those exposed to warm temperatures, which can indicate that colder birds are able to produce more energy. If mitochondria can produce more energy in colder temperatures, individuals are capable of increasing heat generation and maintain a high body temperature in these conditions when exposed to them at early ages. Birds moved to the common environment largely maintained their responses to their developmental temperature. This indicates that exposure to heatwaves or cold spells until birds are fully grown affects mitochondrial function at least until 20 weeks, and effects remain even when birds are moved to an optimal temperature. Variation between the sexes was also detected, as females had higher respiration compared to males and a higher proportion of respiratory capacity of the mitochondria that is not being used to its full potential to drive energy production. Additionally, a higher oxygen consumption coupled with energy production suggests a greater ability to respond to energetic stress by enhancing energy-producing respiration, if necessary, which could be related to reproduction costs such as egg production and laying.
Conservation efforts benefit from understanding physiological responses to adverse temperatures, which can help predict how populations are affected by climate change. These results are the first steps in identifying the possible long-term repercussions of exposure to extreme weather events during development. Physiological responses to cold and warm temperatures during development did not revert to the expected response when individuals were moved into a common environment as adults, at least until the end of the experiment. This suggests that developmental temperature had long-lasting effects on mitochondrial metabolism, which raises concerns regarding exposure to both heatwaves and cold spells at early ages. Although, it is still uncertain to what extent developmental temperatures can impact thermal tolerance and performance later in life. Further research is necessary to provide concrete evidence of how temperature during development can affect animals, and consequently impact growth, reproduction and overall fitness.
Master’s Degree Project in Biology 60 credits 2023
Department of Biology, Lund University
Advisor: Andreas Nord, Elisa Thoral
Department of Biology (Less)
Please use this url to cite or link to this publication:
http://lup.lub.lu.se/student-papers/record/9136003
- author
- Correia, Maria
- supervisor
-
- Andreas Nord LU
- Elisa Thoral LU
- organization
- course
- BION03 20221
- year
- 2023
- type
- H2 - Master's Degree (Two Years)
- subject
- language
- English
- id
- 9136003
- date added to LUP
- 2023-09-01 13:33:08
- date last changed
- 2023-09-01 13:33:08
@misc{9136003,
abstract = {{Extreme weather events, such as heatwaves and cold spells, are predicted to increase under climate change, which can have significant negative effects on fitness and survival of wildlife. If such variations are timed during development, they can affect growth and subsequent performance in birds, with influence over long-term temperature tolerance. Developmental temperature can also have direct effects on the ontogeny of the metabolic machinery, including on mitochondrial function, but it is not well understood how this might influence growth and maturation. Since mitochondria produce most of the energy used by the organism (in the form of adenosine triphosphate, ATP), studying how these organelles respond to thermal variations can provide insight into the cellular mechanism underlying key processes such as growth and thermoregulatory capacity, and how these might differ between life-stages. To investigate this, Japanese quail were raised in warm and cold temperatures, from hatching until adulthood, and mitochondrial function was measured in blood cells at key developmental time points. After sexual maturity, half of the birds from each group were placed in a common garden at an intermediate temperature to test whether changes to the mitochondrial phenotype were plastic or programmed by early-life thermal conditions. Overall, there was an increase in mitochondrial metabolism from hatching until 20 weeks (i.e., at the end of the study) in all treatments. Mitochondrial coupling efficiency was the most efficient during early developmental stages at 3 weeks, although it did not differ afterwards. Individuals raised in the warm treatment had a lower baseline and ATP-producing respiration compared to those exposed to cold temperatures. Birds moved to the common garden largely maintained their phenotypic responses to their developmental temperature, indicating long-lasting effects to long-term exposure of suboptimal temperatures. Variation between the sexes was also detected, as females had higher mitochondrial efficiency compared to males in all treatments, even when moved to a different thermal environment. Adult males exposed to cold temperatures during development showed decrease in reserve capacity, in contrary to those reared in warmer temperatures. This study can provide insight into how mitochondrial metabolism develops in birds and how it can be impacted by immediate climate change effects, such as extreme weather events, by evaluating contrasts throughout different life-stages.}},
author = {{Correia, Maria}},
language = {{eng}},
note = {{Student Paper}},
title = {{From Hatchling to Adulthood: Exploring the Effects of Developmental Temperature on Mitochondrial Function in Japanese quail (Coturnix japonica)}},
year = {{2023}},
}