Nitrogen metabolism in tambaqui (Colossoma macropomum), a neotropical model teleost: hypoxia, temperature, exercise, feeding, fasting, and high environmental ammonia

Wood, Chris M.; Souza Netto, José Gadelha de; Wilson, Jonathan; Duarte, Rafael Mendonça; Val, Adalberto Luis

Artigo

Nitrogen metabolism in tambaqui (Colossoma macropomum), a neotropical model teleost: hypoxia, temperature, exercise, feeding, fasting, and high environmental ammonia

The total rate of N-waste excretion (MN) in juvenile tambaqui living in ion-poor Amazonian water comprised 85 % ammonia-N (MAmm-N) and 15 % urea-N (MUrea-N). Both occurred mainly across the gills with only ~5 % of MAmm-N and ~39 % of MUrea-N via the urine. Tambaqui were not especially tolerant to hi...

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Autor principal:	Wood, Chris M.
Outros Autores:	Souza Netto, José Gadelha de, Wilson, Jonathan, Duarte, Rafael Mendonça, Val, Adalberto Luis
Grau:	Artigo
Idioma:	English
Publicado em:	Journal of Comparative Physiology B: Biochemical, Systemic, and Environmental Physiology 2020
Assuntos:	Ammonia Nitrogen Urea Animals Animals Experiment Characiformes Environment Feeding Behavior Gill Hypoxia Kidney Metabolism Oxygen Consumption Temperature Ammonia Animal Characiformes Environment Feeding Behavior Gills Hypoxia Kidney Nitrogen Oxygen Consumption Physical Conditioning, Animals Temperature Urea
Acesso em linha:	https://repositorio.inpa.gov.br/handle/1/17208

id	oai:repositorio:1-17208
recordtype	dspace
spelling	oai:repositorio:1-17208 Nitrogen metabolism in tambaqui (Colossoma macropomum), a neotropical model teleost: hypoxia, temperature, exercise, feeding, fasting, and high environmental ammonia Wood, Chris M. Souza Netto, José Gadelha de Wilson, Jonathan Duarte, Rafael Mendonça Val, Adalberto Luis Ammonia Nitrogen Urea Animals Animals Experiment Characiformes Environment Feeding Behavior Gill Hypoxia Kidney Metabolism Oxygen Consumption Temperature Ammonia Animal Characiformes Environment Feeding Behavior Gills Hypoxia Kidney Nitrogen Oxygen Consumption Physical Conditioning, Animals Temperature Urea The total rate of N-waste excretion (MN) in juvenile tambaqui living in ion-poor Amazonian water comprised 85 % ammonia-N (MAmm-N) and 15 % urea-N (MUrea-N). Both occurred mainly across the gills with only ~5 % of MAmm-N and ~39 % of MUrea-N via the urine. Tambaqui were not especially tolerant to high environmental ammonia (HEA), despite their great resistance to other environmental factors. Nevertheless, they were able to maintain a continued elevation of MAmm-N during and after 48-h exposure to 2.5 mmol L−1 HEA. The normally negative transepithelial potential (−18 mV) increased to −9 mV during the HEA period, which would help to reduce branchial NH4 + entry. During 3 h of acute environmental hypoxia (30 % saturation), MAmm-N declined, and recovered thereafter, similar to the response seen in other hypoxia-tolerant teleosts; MUrea-N did not change. However, during gradual hypoxia, MAmm-N remained constant, but MUrea-N eventually fell. The acute temperature sensitivities of MAmm-N and MN were low from 28 °C (acclimation) to 33 °C (Q10 ~1.5), but high (~3.8) from 33 to 38 °C, relative to MO2 (~1.9 throughout). In contrast, MUrea-N exhibited a different pattern over these temperature ranges (Q10 2.6 and 2.1, respectively). The nitrogen quotient (NQ = 0.16–0.23) was high at all temperatures, indicating a 60–85 % reliance on protein to fuel aerobic metabolism in these fasting animals. During steady-state aerobic exercise, MO2 and MUrea-N increased in parallel with velocity (up to 3.45 body lengths s−1), but MAmm (and thus MN) remained approximately constant. Therefore, the NQ fell progressively, indicating a decreasing reliance on protein-based fuels, as work load increased. In group feeding trials using 45 % protein commercial pellets, tambaqui excreted 82 % (range 39–170 %) of the dietary N within 24 h; N-retention efficiency was inversely related to the ration voluntarily consumed. MAmm-N peaked at 4–6 h, and MUrea-N at 6–9-h post-feeding, with an additional peak in MAmm-N only at 21 h. During subsequent fasting, MN stabilized at a high endogenous rate from 2 through 8 days post-feeding. Possible reasons for the high wasting of protein-N during both fasting and feeding are discussed. © 2016, Springer-Verlag Berlin Heidelberg. 2020-06-15T21:39:59Z 2020-06-15T21:39:59Z 2017 Artigo https://repositorio.inpa.gov.br/handle/1/17208 10.1007/s00360-016-1027-8 en Volume 187, Número 1, Pags. 135-151 Restrito Journal of Comparative Physiology B: Biochemical, Systemic, and Environmental Physiology
institution	Instituto Nacional de Pesquisas da Amazônia - Repositório Institucional
collection	INPA-RI
language	English
topic	Ammonia Nitrogen Urea Animals Animals Experiment Characiformes Environment Feeding Behavior Gill Hypoxia Kidney Metabolism Oxygen Consumption Temperature Ammonia Animal Characiformes Environment Feeding Behavior Gills Hypoxia Kidney Nitrogen Oxygen Consumption Physical Conditioning, Animals Temperature Urea
spellingShingle	Ammonia Nitrogen Urea Animals Animals Experiment Characiformes Environment Feeding Behavior Gill Hypoxia Kidney Metabolism Oxygen Consumption Temperature Ammonia Animal Characiformes Environment Feeding Behavior Gills Hypoxia Kidney Nitrogen Oxygen Consumption Physical Conditioning, Animals Temperature Urea Wood, Chris M. Nitrogen metabolism in tambaqui (Colossoma macropomum), a neotropical model teleost: hypoxia, temperature, exercise, feeding, fasting, and high environmental ammonia
topic_facet	Ammonia Nitrogen Urea Animals Animals Experiment Characiformes Environment Feeding Behavior Gill Hypoxia Kidney Metabolism Oxygen Consumption Temperature Ammonia Animal Characiformes Environment Feeding Behavior Gills Hypoxia Kidney Nitrogen Oxygen Consumption Physical Conditioning, Animals Temperature Urea
description	The total rate of N-waste excretion (MN) in juvenile tambaqui living in ion-poor Amazonian water comprised 85 % ammonia-N (MAmm-N) and 15 % urea-N (MUrea-N). Both occurred mainly across the gills with only ~5 % of MAmm-N and ~39 % of MUrea-N via the urine. Tambaqui were not especially tolerant to high environmental ammonia (HEA), despite their great resistance to other environmental factors. Nevertheless, they were able to maintain a continued elevation of MAmm-N during and after 48-h exposure to 2.5 mmol L−1 HEA. The normally negative transepithelial potential (−18 mV) increased to −9 mV during the HEA period, which would help to reduce branchial NH4 + entry. During 3 h of acute environmental hypoxia (30 % saturation), MAmm-N declined, and recovered thereafter, similar to the response seen in other hypoxia-tolerant teleosts; MUrea-N did not change. However, during gradual hypoxia, MAmm-N remained constant, but MUrea-N eventually fell. The acute temperature sensitivities of MAmm-N and MN were low from 28 °C (acclimation) to 33 °C (Q10 ~1.5), but high (~3.8) from 33 to 38 °C, relative to MO2 (~1.9 throughout). In contrast, MUrea-N exhibited a different pattern over these temperature ranges (Q10 2.6 and 2.1, respectively). The nitrogen quotient (NQ = 0.16–0.23) was high at all temperatures, indicating a 60–85 % reliance on protein to fuel aerobic metabolism in these fasting animals. During steady-state aerobic exercise, MO2 and MUrea-N increased in parallel with velocity (up to 3.45 body lengths s−1), but MAmm (and thus MN) remained approximately constant. Therefore, the NQ fell progressively, indicating a decreasing reliance on protein-based fuels, as work load increased. In group feeding trials using 45 % protein commercial pellets, tambaqui excreted 82 % (range 39–170 %) of the dietary N within 24 h; N-retention efficiency was inversely related to the ration voluntarily consumed. MAmm-N peaked at 4–6 h, and MUrea-N at 6–9-h post-feeding, with an additional peak in MAmm-N only at 21 h. During subsequent fasting, MN stabilized at a high endogenous rate from 2 through 8 days post-feeding. Possible reasons for the high wasting of protein-N during both fasting and feeding are discussed. © 2016, Springer-Verlag Berlin Heidelberg.
format	Artigo
author	Wood, Chris M.
author2	Souza Netto, José Gadelha de Wilson, Jonathan Duarte, Rafael Mendonça Val, Adalberto Luis
author2Str	Souza Netto, José Gadelha de Wilson, Jonathan Duarte, Rafael Mendonça Val, Adalberto Luis
title	Nitrogen metabolism in tambaqui (Colossoma macropomum), a neotropical model teleost: hypoxia, temperature, exercise, feeding, fasting, and high environmental ammonia
title_short	Nitrogen metabolism in tambaqui (Colossoma macropomum), a neotropical model teleost: hypoxia, temperature, exercise, feeding, fasting, and high environmental ammonia
title_full	Nitrogen metabolism in tambaqui (Colossoma macropomum), a neotropical model teleost: hypoxia, temperature, exercise, feeding, fasting, and high environmental ammonia
title_fullStr	Nitrogen metabolism in tambaqui (Colossoma macropomum), a neotropical model teleost: hypoxia, temperature, exercise, feeding, fasting, and high environmental ammonia
title_full_unstemmed	Nitrogen metabolism in tambaqui (Colossoma macropomum), a neotropical model teleost: hypoxia, temperature, exercise, feeding, fasting, and high environmental ammonia
title_sort	nitrogen metabolism in tambaqui (colossoma macropomum), a neotropical model teleost: hypoxia, temperature, exercise, feeding, fasting, and high environmental ammonia
publisher	Journal of Comparative Physiology B: Biochemical, Systemic, and Environmental Physiology
publishDate	2020
url	https://repositorio.inpa.gov.br/handle/1/17208
_version_	1787142953407348736
score	11.653393

Nitrogen metabolism in tambaqui (Colossoma macropomum), a neotropical model teleost: hypoxia, temperature, exercise, feeding, fasting, and high environmental ammonia

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