TY - JOUR
T1 - Effects of short- and long-term glucan feeding of rainbow trout (Salmonidae) on the susceptibility to Ichthyophthirius multifiliis infections
AU - Lauridsen, Jesper Hauberg
AU - Buchmann, Kurt
PY - 2010
Y1 - 2010
N2 - Background. Various compounds are being used as immuno-stimulants in various aquaculture feed types but the importance of their prolonged use is at present unknown. It is also true for those intended to modify trout susceptibility to white spot disease caused by Ichthyophthirius multifiliis. The immuno-modulating effects on rainbow trout of short- and long-term feeding using dry feed with inclusion of beta-glucan (0.2%) have therefore been evaluated. Materials and Methods. The immune reactivity was assessed by measuring susceptibility to I. multifiliis infections and plasma lysozyme in the host, factors which are considered innate response parameters. Rainbow trout, Oncorhynchus mykiss (Walbaum, 1792) (Actinopterygii: Salmoniformes: Salmonidae), were fed (control feed or glucan-containing feed) for 14 or 35 days before challenge (exposure to infective I. multifiliis theronts) and the resulting infection (number of trophonts in the skin) was recorded on day 11 post-exposure to theronts. Results. All fish obtained infection following parasite exposure but glucan-fed fish showed a lower infection at day 46 compared to fish fed control-feed. The lysozyme activity of fish plasma was evaluated throughout the experimental period and found slightly but significantly increased in association with glucan feeding at day 14, 17, and 46. Conclusion. No evidence for an exhaustion of these selected innate response parameters due to prolonged glucan- feeding could be detected within the experimental period of 46 days.
AB - Background. Various compounds are being used as immuno-stimulants in various aquaculture feed types but the importance of their prolonged use is at present unknown. It is also true for those intended to modify trout susceptibility to white spot disease caused by Ichthyophthirius multifiliis. The immuno-modulating effects on rainbow trout of short- and long-term feeding using dry feed with inclusion of beta-glucan (0.2%) have therefore been evaluated. Materials and Methods. The immune reactivity was assessed by measuring susceptibility to I. multifiliis infections and plasma lysozyme in the host, factors which are considered innate response parameters. Rainbow trout, Oncorhynchus mykiss (Walbaum, 1792) (Actinopterygii: Salmoniformes: Salmonidae), were fed (control feed or glucan-containing feed) for 14 or 35 days before challenge (exposure to infective I. multifiliis theronts) and the resulting infection (number of trophonts in the skin) was recorded on day 11 post-exposure to theronts. Results. All fish obtained infection following parasite exposure but glucan-fed fish showed a lower infection at day 46 compared to fish fed control-feed. The lysozyme activity of fish plasma was evaluated throughout the experimental period and found slightly but significantly increased in association with glucan feeding at day 14, 17, and 46. Conclusion. No evidence for an exhaustion of these selected innate response parameters due to prolonged glucan- feeding could be detected within the experimental period of 46 days.
KW - Former LIFE faculty
KW - Rainbow trout, white spot disease, ich, Ichthyophthirius multifiliis, beta-glucan, immunostimulants, immunity
U2 - 10.3750/AIP2010.40.1.08
DO - 10.3750/AIP2010.40.1.08
M3 - Journal article
SN - 0137-1592
VL - 40
SP - 61
EP - 66
JO - Acta Ichthyologica et Piscatoria
JF - Acta Ichthyologica et Piscatoria
IS - 1
ER -