The genus
We hypothesized that both larvae and adults of the heat and hypoxia‐adapted Tabasco‐line of the Nile tilapia
A radical relay strategy for mono- and di-halogenation (iodination, bromination, and chlorination) of sp3C–H bonds has been developed. This first example of double, geminal C–H functionalization is enabled
- Award ID(s):
- 1654656
- NSF-PAR ID:
- 10074246
- Publisher / Repository:
- Royal Society of Chemistry (RSC)
- Date Published:
- Journal Name:
- Chemical Science
- Volume:
- 9
- Issue:
- 19
- ISSN:
- 2041-6520
- Page Range / eLocation ID:
- 4500 to 4504
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Oreochromis is among the most popular of the tilapiine cichlid tribe for aquaculture. However, their temperature and hypoxia tolerance, if tested at all, is usually tested at temperatures of 20–25°C, rather than at the considerably higher temperatures of 30–35°C typical of tropical aquaculture.Oreochromis niloticus would be relatively hypoxia‐tolerant. Oxygen consumption rate (), Q10and aquatic surface respiration (ASR) was measured using closed respirometry at 2 ( c . 0.2 g), 30 (c . 2–5 g), 105c . (10–15 g) and 240 (c . 250 g) days of development, at 25°C, 30°C and 35°C.at 30°C was inversely related to body mass: c . 90 μM O2g−1/h in larvae down toc . 1 μM O2g−1/h in young adults. Q10forwas typical for fish over the range 25–35°C of 1.5–2.0. ASR was exhibited by 50% of the fish at pO2of 15–50 mmHg in a temperature‐dependent fashion. However, the largest adults showed notable ASR only when pO2fell to below 10 mmHg. Remarkably, pcritfor was 12–17 mmHg at 25–30°C and still only 20–25 mmHg across development at 35°C. These values are among the lowest measured for teleost fishes. Noteworthy is that all fish maintain equilibrium, ventilated their gills and showed routine locomotor action for 10–20 min after ceased at near anoxia and when then returned to oxygenated waters, all fish survived, further indicating a remarkable hypoxic tolerance. Remarkably, data assembled for from >30 studies showed a > x2000 difference, which we attribute to calculation or conversion errors. Nonetheless, pcritwas very low for all Oreochromis sp. and lowest in the heat and hypoxia‐adapted Tabasco line. -
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