RT Journal Article
T1 Determination of optimal degree days of fasting before slaughter in rainbow trout (Oncorhynchus mykiss)
A1 Bermejo Poza, Rubén
A1 Fuente Vázquez, Jesús De La
A1 Pérez Marcos, Concepción
A1 González De Chávarri Echániz, Elisabeth
A1 Díaz Díaz Chirón, María Teresa
A1 Torrent, Fernando
A1 Villarroel, Morris
AB Pre-slaughter fasting is a common practice in aquaculture to ensure emptying of the digestive tract, but little is known about how long fish should be fasted, in terms of degree days (°C days), to clear the gut without affecting their welfare or flesh quality. In this study, 180 rainbow trout (Oncorhynchus mykiss) were fasted for 3, 4, 5, 6, 7 and 9 days (17.2, 22.3, 28.6, 35.3, 41.8 and 55.3 °C days, respectively) and different morphometric, hematological and flesh quality parameters were measured. The slaughter weight, relative growth and hepato-somatic index did not decrease until after 7 days of fasting (41.8 °C days) and stomach content was similar and near zero after 4 days of fasting (22.3 °C days). Conversely, fasting time increased carcass yield. Plasma concentrations of cortisol, glucose and creatine phosphokinase enzyme were lower with increasing days of fasting. However, trout slaughtered after 5 days of fasting (28.6 °C days) had a higher flesh pH at 0 h post-mortem than 3 and 4 days fasted trout and, consequently, earlier establishment of rigor mortis. Furthermore, liver color could be useful as a stress indicator since its hue decreases after 5 days of fasting (28.6 °C days). In conclusion, a pre-slaughter fasting period from 17.2 °C days to 22.3 °C days makes possible to obtain a complete emptying of the digestive system in rainbow trout and simultaneously it can minimize the stress response with consequent better flesh quality.
PB Elsevier
SN 0044-8486
YR 2017
FD 2017-02-17
LK https://hdl.handle.net/20.500.14352/116449
UL https://hdl.handle.net/20.500.14352/116449
LA eng
NO Bermejo-Poza, R., De la Fuente, J., Pérez, C., de Chavarri, E. G., Diaz, M. T., Torrent, F., & Villarroel, M. (2017). Determination of optimal degree days of fasting before slaughter in rainbow trout (Oncorhynchus mykiss). Aquaculture, 473, 272-277.
NO Ministerio de Economía y Competitividad (España)
DS Docta Complutense
RD 24 abr 2025