home    about    browse    search    latest    help 
Login | Create Account

Comparative In Vitro and In Vivo Effects of Feed Additives on Rainbow Trout Response to Ichthyophthirius multifiliis

Mathiessen, Heidi; Jaafar, Rzgar Mohammad; Al-Jubury, Azmi; von Gersdorff Jørgensen, Louise; Kania,, per Walter and Buchmann, Kurt (2021) Comparative In Vitro and In Vivo Effects of Feed Additives on Rainbow Trout Response to Ichthyophthirius multifiliis. [Sammenligning af In Vitro og In Vivo effekter af foder additiver på regnbueørredens reaktion på infektion med Ichthyophthirius multifiliis (”Fiskedræber”).] North American Journal of Aquaculture, online, pp. 1-11.

[thumbnail of Mathiessen et al 2021. Herbal and ICH - NAJA.pdf] PDF - English


Control of the skin parasitic ciliate Ichthyophthirius multifiliis is currently based on laborious chemical and mechanical approaches, thus advocating for alternative control measures. Here, we show that the early development of trophonts (feeding stage residing in the epidermis) in the Rainbow Trout Oncorhynchus mykiss epidermis was inhib-ited at 5 d postinfection after the administration of feed additives, including garlic Allium sativum, oregano Origanum onites, thyme Thymus vulgaris, coriander Coriandrum sativum, and astaxanthin (a carotenoid derived from the alga Haematococcus pluvialis). However, no inhibition was observed at 8 d postinfection. We investigated whether the early inhibition was caused by (1) the feed additives’ direct effect on the parasite and/or (2) stimulation of the Rainbow Trout immune responses. Garlic exhibited the highest in vitro killing capacity toward theronts (the infective stage of the parasite), followed by oregano, thyme, and astaxanthin, whereas coriander had no in vitro parasiticidal effect. Immune reactions were measured by plasma lysozyme activity in Rainbow Trout after feeding and by recording immune gene expression in trout leukocytes that were exposed to feed additives. Oregano-fed fish showed a signifi-cantly (P < 0.05) elevated plasma lysozyme activity. Oregano and thyme—and to a lesser extent, garlic, astaxanthin, and coriander—induced a significant regulation of innate and adaptive immune genes in vitro. The results suggest that the investigated additives inhibit early parasite development directly as well as indirectly (i.e., by elevating the host immune response).

Summary translation

Bekæmpelse af hudparasitten “fiskedræber” - ciliaten Ichthyophthirius multifiliis sker p.t. mekanisk eller ved brug af kemiske hjælpestoffer, hvorfor der er behov for at udvikle alternative behandlingsmetoder. I denne undersøgelse blev der vist en hæmning i udviklingen af trophonter (parasittens æde-stadium i fiskens hud) hos regnbueørred Oncorhynchus mykiss efter 5 dages fodring med foder tilsat additiver som hvidløg, oregano, timian, koriander og astaxanthin (et pigment udvundet fra algen Haematococcus pluvialis). Hæmningen ophørte dog på 8. dagen. Det blev undersøgt hvorvidt tidlig hæmning skyldtes (1) en direkte effekt af additivet på parasitten og/eller (2) stimulering af regnbueørredens immunrespons. Hvidløg viste størst in vitro effekt over for theronterne, efterfulgt af oregano, timian og astaxanthin, mens koriander ikke havde nogen effekt. Resultaterne tyder på, at de undersøgte foder additiver hæmmer parasittens udvikling såvel direkte som indirekte ved at stimulere fiskens eget immunrespons.

EPrint Type:Journal paper
Keywords:Alternative anti-parasitic substances, Feed Additives, Rainbow Trout, Immune Response, Ichthyophthirius multifiliis, garlic, oregano, thyme, coriander, astaxanthin
Agrovoc keywords:
Subjects: Animal husbandry > Health and welfare
Research affiliation: Denmark > Organic RDD 4 > ShelterFish
Deposited By: Jokumsen, Senior Advisory Scientist Alfred
ID Code:39607
Deposited On:07 Apr 2021 08:10
Last Modified:07 Apr 2021 08:10
Document Language:English
Refereed:Peer-reviewed and accepted

Repository Staff Only: item control page


Downloads per month over past year

View more statistics