Effects of Pro-Tex on zebrafish (Danio rerio) larvae, adult common carp (Cyprinus carpio) and adult yellowtail kingfish (Seriola lalandi).
Aquaculture practices bring several stressful events to fish. Stressors not only activate the hypothalamus-pituitary-interrenal-axis, but also evoke cellular stress responses. Up-regulation of heat shock proteins (HSPs) is among the best studied mechanisms of the cellular stress response. An extract of the prickly pear cactus (Opuntia ficus indica), Pro-Tex, a soluble variant of TEX-OE(®), may induce expression of HSPs and reduce negative effects of cellular stress. Pro-Tex therefore is used to ameliorate conditions during stressful aquaculture-related practices. We tested Pro-Tex in zebrafish (Danio rerio), common carp (Cyprinus carpio L.) and yellowtail kingfish (Seriola lalandi) exposed to aquaculture-relevant stressors (thermal stress, net confinement, transport) and assessed its effects on stress physiology. Heat shock produced a mild increase in hsp70 mRNA expression in 5-day-old zebrafish larvae. Pro-Tex increased basal hsp70 mRNA expression, but decreased heat-shock-induced expression of hsp70 mRNA. In carp, Pro-Tex increased plasma cortisol and glucose levels, while it did not affect the mild stress response (increased plasma cortisol and glucose) to net confinement. In gills, and proximal and distal intestine, stress increased hsp70 mRNA expression; in the distal intestine, an additive enhancement of hsp70 mRNA expression by Pro-Tex was seen under stress. In yellowtail kingfish, Pro-Tex reduced the negative physiological effects of transport more efficiently than when fish were sedated with AQUI-S(®). Overall, our data indicate that Pro-Tex has protective effects under high levels of stress only. As Pro-Tex has potential for use in aquaculture, its functioning and impact on health and welfare of fish should be further studied.
Organismal Animal Physiology, IWWR, Radboud University Nijmegen, Heijendaalseweg 135, 6525 AJ, Nijmegen, The Netherlands, J.Boerrigter@science.ru.nl.
Jeroen G J
JG
Boerrigter
Hans W
HW
van de Vis
Ruud
R
van den Bos
Wout
W
Abbink
Tom
T
Spanings
Jan
J
Zethof
Laura Louzao
LL
Martinez
Wouter F M
WF
van Andel
Javier
J
Lopez-Luna
Gert
G
Flik
D000818:Animals; D017756:Aquaculture / Q000379:methods; D001786:Blood Glucose / Q000032:analysis; D002347:Carps / Q000378:metabolism*; D017931:DNA Primers / Q000235:genetics; D004305:Dose-Response Relationship, Drug; D005786:Gene Expression Regulation / Q000187:drug effects*; D006360:Heat-Shock Proteins / Q000378:metabolism; D006854:Hydrocortisone / Q000097:blood; D019344:Lactic Acid / Q000097:blood; D007814:Larva / Q000187:drug effects / Q000378:metabolism; D029747:Opuntia / Q000737:chemistry*; D010473:Perciformes / Q000378:metabolism*; D010936:Plant Extracts / Q000494:pharmacology*; D060888:Real-Time Polymerase Chain Reaction; D018709:Statistics, Nonparametric; D013312:Stress, Physiological / Q000187:drug effects / Q000502:physiology*; D013696:Temperature; D015027:Zebrafish / Q000378:metabolism*
D001786:Blood Glucose; D017931:DNA Primers; D006360:Heat-Shock Proteins; D010936:Plant Extracts; D019344:Lactic Acid; D006854:Hydrocortisone