Effects of temperature decrease on feeding rates, immune indicators and histopathological changes of gilthead sea bream Sparus aurata fed with an experimental diet

Thermal imprinting modifies bone homeostasis in cold challenged sea bream (Sparus aurata, L.)

“…maintained at 23±1°C. These results are in line with other studies of cold-challenged sea bream, in which body mass was not affected by low water temperatures (Tort et al, 2004), although HSI was increased as a consequence of the failure to mobilize fat stores (Ibarz et al, 2005(Ibarz et al, , 2007. We propose that the maintenance of body mass and K in the present study indicates that sea bream were able to adjust their metabolism to compensate for the effects of a short-term (15 days) cold challenge, as has been shown for other fish (Hochachka and Somero, 1984).…”

“…In line with previous reports, a decrease in water temperature was associated with a significant reduction in feed intake, which is one of the first signs of cold stress (Tort et al, 2004). However, in the present study, irrespective of thermal history, the reduction in feed intake as a consequence of a drop in water temperature did not affect body mass or K, which was similar to the matched controls ocn, ogn1 and ogn2.…”

“…Furthermore, increased plasma glucose (a secondary stress marker; Pottinger and Pickering, 1997) was only observed in the HLT group when fish were exposed to 13°C for 15 days. However, the results from several previous studies suggest that the development of hyperglycaemia in response to a cold challenge is variable in this species Tort et al, 2004;Vargas-Chacoff et al, 2009). Notably, the only group that was hyperglycaemic in our experiments (the HLT group) was also the group that had significantly higher plasma cortisol (108.4 ±71.4 ng ml −1 ).…”

“…This syndrome is a multifactorial condition associated with a high but transient (24-48 h) rise in plasmatic levels of cortisol and triggers a classical stress response with the associated secondary effects (Rotllant et al, 2000;SalaRabanal et al, 2003). A reduction in food intake (Rotllant et al, 2000;Tort et al, 2004) or starvation (Ibarz et al, , 2005(Ibarz et al, , 2007 occurs and fish affected by winter syndrome become lethargic. Immunocompetence is also severely depressed (Berthe et al, 1995;Doménech et al, 1997;Tort et al, 1998;Vargas-Chacoff et al, 2009), osmoregulatory capacity is impaired (Ibarz et al, 2010a), and histopathological changes occur in the liver, exocrine pancreas, digestive tract and muscle Ibarz et al, 2010a, b;Sala-Rabanal et al, 2003).…”

Physiological responses of Chinese longsnout catfish to water temperature

“…Similarly, Langston et al (2002) noted that lysozyme activity was higher in Atlantic halibut Hippoglossus hippoglossus L. that were acclimated to higher temperatures. In gilthead sea bream, Sparus aurata, lysozyme activity decreased significantly when transferred from 18°C to 11°C (Tort et al, 2004). Likewise, Ndong et al (2007) found that lysozyme activity decreased significantly when juvenile tilapia Oreochromis mossambicus were transferred from 27°C to 19°C after 12-96 h, but increased significantly when transferred to 31°C and 35°C over 48-96 h. Conversely, some studies have not found an effect of water temperature on serum lysozyme levels (Olsen et al, 1993).…”