Hematological responses to thermal acclimation in a cold water squaliform (Heterodontus francisci girard)

Elasmobranch Responses to Experimental Warming, Acidification, and Oxygen Loss—A Meta-Analysis

“…In addition to increasing oxygen demands, oxygen affinity typically decreases with temperature (Nikinmaa et al, 2019), and several elasmobranch species have been shown to adjust their hematological profile in response to environmental challenges, namely temperature (Butler and Taylor, 1975;Neale et al, 1977;Bouyoucos et al, 2020a;Pegado et al, 2020b). However, no significant overall effect was detected for EW or EA for the endpoints analyzed here, with insufficient data to conduct the analysis for EWA (Figure 5E; Supplementary Table 3).…”

“…Indeed, this specific response was only possible to analyze in the context of EW, for which no significant net effects were detected (Figure 6F; Supplementary Table 3). However, it is worth noting that two of the studies included in this analysis measured the effects of EW over testosterone concentrations, both reporting significant differences although in opposite directions (Neale et al, 1977;Mull et al, 2008). This disparity reflects the context specificity of this response, highlighting the need for more research, particularly considering potential repercussions over reproduction.…”

“…Excluded were studies (or individual responses) that (i) lacked a suitable control treatment, TABLE 1 | Summary of the references including in the analysis across the different treatments, namely experimental warming (EW), acidification (EA), deoxygenation (ED), and their combination (EWA and EWD). Neale et al, 1977;Du Preez et al, 1988;Fangue and Bennett, 2003;Tullis and Baillie, 2005;Mull et al, 2008;Rodda and Seymour, 2008;Dabruzzi et al, 2013;Rosa et al, 2014Rosa et al, , 2016aDi Santo, 2015, 2016Pistevos et al, 2015;Johnson et al, 2016;Whitney et al, 2016;Lear et al, 2017;Pistevos et al, 2017Pistevos et al, , 2019Luongo and Lowe, 2018;Pouca et al, 2018Pouca et al, , 2019Di Santo, 2019;Hume, 2019;Schwieterman et al, 2019;Bouyoucos et al, 2020a,c;Crear et al, 2020;Musa et al, 2020;Pegado et al, 2020b;Gervais et al, 2021;Wheeler et al, 2021 EA Green andJutfelt, 2014;Heinrich et al, 2014Heinrich et al, , 2016Rosa et al, 2014Rosa et al, , 2016aDi Santo, 2015, 2016Dixson et al, 2015;Pistevos et al, 2015Pistevos et al, , 2017…”

“…Temperature has long been acknowledged as a key modulator of biological processes and its effects have been experimentally studied for decades (Britton, 1924;Neale et al, 1977). Not surprisingly, of the climate change-related factors considered here, the most often investigated in an experimental setting is EW (Figure 1A).…”

A product of its environment: the epaulette shark (Hemiscyllium ocellatum) exhibits physiological tolerance to elevated environmental CO2

“…Following ∼90 days of CO 2 exposure, epaulette sharks exhibited a significant increase in [Hb] and MCHC. Short-term changes in haematological parameters have been documented in teleosts and elasmobranchs following capture, cannulation and exercise ( Soivio et al , 1973 ; Wood et al , 1977 ; Turner et al , 1983 ; Wells et al , 1986 ), upon acclimation to elevated temperature (adult horn sharks, Heterodontus francisci ; Neale et al , 1977 ) and in response to anoxia (grey carpet shark, Chiloscyllium punctatum , and epaulette shark; Chapman and Renshaw, 2009 ). In teleosts, acute changes can be associated with adrenergic red blood cell (RBC) swelling ( Caldwell et al , 2006 ), a mechanism in place to protect RBC pH and oxygen transport during stress, but not known to occur in elasmobranchs ( Berenbrink et al , 2005 ).…”