Dataset for: Warmer ambient temperatures reduce protein intake by a mammalian folivore
Data files
Sep 13, 2023 version files 98.82 KB
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2023_Protein_Exp_Data_CORRECTED.xlsx
87.39 KB
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README.md
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Abstract
The interplay between ambient temperature and nutrition in wild herbivores is frequently overlooked, despite the fundamental importance of food. We tested whether different ambient temperatures (10˚C, 18˚C, and 26˚C) influenced the intake of protein by a marsupial herbivore, the common brushtail possum (Trichosurus vulpecula). At each temperature, possums were offered a choice of two foods containing different amounts of protein (57% vs 8%) for one week. Animals mixed a diet with a lower proportion of protein to non-protein (P:NP, 0.20) when held at 26˚C compared to that at both 10˚C and 18˚C (0.22). Since detoxification of plant secondary metabolites imposes a protein cost on animals, we then studied whether addition of the monoterpene 1,8-cineole to the food changed the effect of ambient temperature (10˚C and 26˚C) on food choice. Cineole reduced food intake but also removed the effect of temperature on P:NP ratio and instead animals opted for a diet with higher P:NP (0.19 with cineole vs 0.15 without cineole). These experiments show the proportion of P:NP chosen by animals is influenced by ambient temperature and by plant secondary metabolites. Protein is critical for reproductive success in this species and reduced protein intake caused by high ambient temperatures may limit the viability of some populations in the future.
- Title of Dataset: Warmer ambient temperatures reduce protein intake by a mammalian folivore
- Principal investigator:
Phillipa K Beale
Australian National University
phillipa.beale@gmail.com
Co-authors: Ben D Moore, William J Foley, Karen J Marsh
Summary of dataset collection:
These data were collected using twelve adult male common brushtail possums (Trichosurus vulpecula) which were caught on the Australian National University campus (Canberra, 35.2809° S, 149.1300° E) in November 2016.
The possums were housed inside constant temperature rooms (at 10, 18, or 26 °C ± 2°C) with a 12:12 h light cycle and offered artificial diets prepared daily (composition is described in the uploaded dataset). Food was offered at 1630 h and refusals were collected at 0900 h daily. Dry matter intake (DMI) of the two diets was measured by drying a subsample of the food offered at 80 °C and subtracting the dry mass of all food refusals. In addition, we calculated the daily grams of protein (P) and “non-protein” (NP; sum of fats and non-structural carbohydrates) ingested across 7 days for each possum for each temperature. Possums were weighed weekly.
- Experiment 1: Macronutrient choice at different ambient temperatures
Possums were randomly allocated into three groups of four, and each group was kept at a constant temperature of either 10, 18 or 26 ± 2°C for seven days. The possums were then rotated between the temperature treatments for two more rounds of the experiment, using a randomized crossover design so the number of observations on each treatment was n=12.
- Experiment 2: The effects of ambient temperature and 1,8-cineole on macronutrient choice
Possums were randomly allocated into two groups. One group was kept at 26 ± 2°C for seven nights, while the other was kept at 10 ± 2°C. Possums were offered the two diets differing in macronutrient composition for the first six nights. DMI and diet preferences were measured on the fifth and sixth nights and the mean was taken as an estimate of intake of the basal diets. On the seventh night 1,8-cineole was added to both diets at a concentration of 2.45% WM (~7% DM) and DMI and diet preferences were measured again over two nights.
- pretrial: the data set also includes results from a short acclimation period between the two experiments to introduce cineole to the possums less suddenly. The results from this period were not used in the final analysis of the data for publication.
Abbreviations used:
- HP = high protein diet
- LP = low protein diet
- DMI = dry matter intake
- WM = Wet matter
- O/N = overnight
Description of the data and file structure
Number of files: 1
Number of tabs: 9 (described below)
Info: General information about the experiments including number of animals, time of food collection, and weights of animals in grams
HP&LP Diets: (HP = high protein diet, LP = low protein diet) A description of the dietary formulation in percentage of WM (%WM)
Designs: Experiment 1 has purple headers and experiment 2 has orange headers.
- Possum (individual animal identifier numbers are used),
- Group (possums were allocated to groups and moved together),
- Round 1 (Which temperature treatment allocated in experimental round 1),
- Round 2 (which temperature treatment allocated in round 2),
- Round 3 (which temperature treatment allocated in round 3).
Raw data 1: The raw data from experiment 1 in terms of...
- exp round (first second or third round of temperature treatments),
- day of round (how many days at that temperature),
- date offered (the date food was given),
- possum (in terms of individual identifier number),
- temp (temperature in degrees celsius of the room, 10, 18 or 26)
- HP offered (WM g) = how much of the high protein diet was offered in grams of wet matter
- HP offered (DM g) = how much of the high protein diet was offered in grams of dry matter, calculated from the percentage of dry matter in dried control samples.
- HP %DM = percentage of dry matter in the high protein diet, based on the control samples
- HP dish (g) = the weight of the dish the high protein food was given in
- dish + HPDM left (g) = weight in grams of the dish and the dried refusals from the high protein diet
- HP DMI (g) = how much of the high protein diet was eaten by the possum in grams of dry matter.
- LP offered (WM g) = how much low protein diet was offered in grams of wet matter
- LP offered (DM g) = how much of the low protein diet was offered in grams of dry matter based on the percentage dry matter in the control sample
- LP %DM = percentage of the low protein diet that is dry matter based on dried control samples
- LP dish (g) = weight in grams of the dish the low protein diet was offered in
- dish +LPDM left (g) = weight in grams of the dish and the dried refusals of the low protein diet
- LP DMI = grams of dry matter intake of the low protein diet
- Proportion of HPvsLP: proportion of high protein diet compared to low protein diet eaten by the possum.
- total DMI = total (HP plus LP) dry matter intake
CONTROLS 1: the controls from experiment 1 which were subsamples from the diets offered that day, dried to calculate dry matter content of the diet.
- Date = date that diet was offered to possums
- HP WM (g) = weight of the wet matter in grams of the high protein diet control subsample
- HP dish (g) = weight of the dish the sample is being dried in in grams
- HP DM (g) = weight in grams of the high protein diet subsample once dried
- HP%DM = percentage of the high protein diet that was dry matter
- LP WM (g) = grams of wet matter of low protein diet being weighed
- LP dish (g) = weight in grams of the dish that the low protein diet subsample is being weighed in
- LP DM (g) = Weight in grams of the low protein diet subsample
- LP%DM = percentage of the low protein diet that is dry matter
- Notes
PRETRIAL: raw data from an acclimation period between experiment 1 and experiment 2 not used in final analysis for publication. Headings are:
- exp round (either half the cineole concentration used in the experiment or the full 7% cineole)
- day of round (day number),
- date offered (the date food was given),
- possum (in terms of individual identifier number),
- temp (temperature in degrees celsius of the room, 10, 18 or 26)
- HP offered (WM g) = how much of the high protein diet was offered in grams of wet matter
- HP offered (DM g) = how much of the high protein diet was offered in grams of dry matter, calculated from the percentage of dry matter in dried control samples.
- HP %DM = percentage of dry matter in the high protein diet, based on the control samples
- HP dish (g) = the weight of the dish the high protein food was given in
- dish + HPDM left (g) = weight in grams of the dish and the dried refusals from the high protein diet
- HP DMI (g) = how much of the high protein diet was eaten by the possum in grams of dry matter.
- LP offered (WM g) = how much low protein diet was offered in grams of wet matter
- LP offered (DM g) = how much of the low protein diet was offered in grams of dry matter based on the percentage dry matter in the control sample
- LP %DM = percentage of the low protein diet that is dry matter based on dried control samples
- LP dish (g) = weight in grams of the dish the low protein diet was offered in
- dish +LPDM left (g) = weight in grams of the dish and the dried refusals of the low protein diet
- LP DMI = grams of dry matter intake of the low protein diet
- Proportion of HPvsLP: proportion of high protein diet compared to low protein diet eaten by the possum.
- total DMI = total (HP plus LP) dry matter intake
PRETRIAL CONTROLS: control subsamples used to calculate dry matter content of the diets offered in the pretrial
- Date = date that diet was offered to possums
- HP WM (g) = weight of the wet matter in grams of the high protein diet control subsample
- HP dish (g) = weight of the dish the sample is being dried in in grams
- HP DM (g) = weight in grams of the high protein diet subsample once dried
- HP%DM = percentage of the high protein diet that was dry matter
- LP WM (g) = grams of wet matter of low protein diet being weighed
- LP dish (g) = weight in grams of the dish that the low protein diet subsample is being weighed in
- LP DM (g) = Weight in grams of the low protein diet subsample
- LP%DM = percentage of the low protein diet that is dry matter
RAW DATA2: raw data collected in the second experiment
- exp round (first or second round of temperature treatments),
- day of round (how many days at that temperature),
- date offered (the date food was given),
- possum (in terms of individual identifier number),
- temp (temperature in degrees celsius of the room, 10, 18 or 26)
- psm = plant secondary metabolite treatment, basal = basal diet (no cineole) or cineole (basal with cineole added)
- HP offered (WM g) = how much of the high protein diet was offered in grams of wet matter
- HP offered (DM g) = how much of the high protein diet was offered in grams of dry matter, calculated from the percentage of dry matter in dried control samples.
- HP %DM = percentage of dry matter in the high protein diet, based on the control samples
- HP dish (g) = the weight of the dish the high protein food was given in
- dish + HPDM left (g) = weight in grams of the dish and the dried refusals from the high protein diet
- HP DMI (g) = how much of the high protein diet was eaten by the possum in grams of dry matter.
- LP offered (WM g) = how much low protein diet was offered in grams of wet matter
- LP offered (DM g) = how much of the low protein diet was offered in grams of dry matter based on the percentage dry matter in the control sample
- LP %DM = percentage of the low protein diet that is dry matter based on dried control samples
- LP dish (g) = weight in grams of the dish the low protein diet was offered in
- dish +LPDM left (g) = weight in grams of the dish and the dried refusals of the low protein diet
- LP DMI = grams of dry matter intake of the low protein diet
- Proportion of HPvsLP: proportion of high protein diet compared to low protein diet eaten by the possum.
- total DMI = total (HP plus LP) dry matter intake
CONTROLS2 = the control subsamples used to calculate dry matter content in experiment 2
- Date = date that diet was offered to possums
- HP WM (g) = weight of the wet matter in grams of the high protein diet control subsample
- HP dish (g) = weight of the dish the sample is being dried in in grams
- HP DM (g) = weight in grams of the high protein diet subsample once dried
- HP%DM = percentage of the high protein diet that was dry matter
- LP WM (g) = grams of wet matter of low protein diet being weighed
- LP dish (g) = weight in grams of the dish that the low protein diet subsample is being weighed in
- LP DM (g) = Weight in grams of the low protein diet subsample
- LP%DM = percentage of the low protein diet that is dry matter
Publication relating to this data set is in preparation and can be found at the following DOI once published. It was supported by grants from the Australian Research Council (DE120101263 and DP140100228) and with support from Society for Experimental Biology and The Company of Biologist:
https://doi.org/10.1098/rstb.2022.0543
These data were collected using twelve adult male common brushtail possums (Trichosurus vulpecula) which were caught in wire cage traps on the Australian National University campus (Canberra, 35.2809° S, 149.1300° E) in November 2016. The possums were housed inside constant temperature rooms (at 10, 18, or 26 °C ± 2°C) with a 12:12 h light cycle and offered artificial diets prepared daily (composition is described in the uploaded dataset). Food was offered at 1630 h and refusals were collected at 0900 h daily. Dry matter intake (DMI) of the two diets was measured by drying a subsample of the food offered at 80 °C and subtracting the dry mass of all food refusals. In addition, we calculated the daily grams of protein (P) and “non-protein” (NP; sum of fats and non-structural carbohydrates) ingested across 7 days for each possum for each temperature. Possums were weighed weekly.
The first experiment tested whether possums balanced macronutrients differently depending on the ambient temperature. The second tested how the addition of a PSM, cineole influenced the effect of ambient temperature on macronutrient balancing.
Experiment 1: Macronutrient choice at different ambient temperatures
Possums were randomly allocated into three groups of four, and each group was kept at a constant temperature of either 10, 18 or 26 ± 2°C for seven days. The possums were then rotated between the temperature treatments for two more rounds of the experiment, using a randomized crossover design so the number of observations on each treatment was n=12.
Experiment 2: The effects of ambient temperature and cineole on macronutrient choice
Possums were randomly allocated into two groups. One group was kept at 26 ± 2°C for seven nights, while the other was kept at 10 ± 2°C. Possums were offered the two diets differing in macronutrient composition without addition of any 1,8-cinoele for the first six nights. DMI and diet preferences were measured on the fifth and sixth nights and the mean was taken as an estimate of intake of the basal diets. On the seventh night 1,8-cineole was added to both diets at a concentration of 2.45% WM (~7% DM) and DMI and diet preferences were measured again over two nights.