Utjecaj zaražavanja patogenom Aphanomyces astaci (Schikora, 1906) na mortalitet i rast mramornog raka Procambarus virginalis (Lyko, 2017)

undergraduate thesis

• Title (english): The effect of infection with crayfish plague pathogen Aphanomyces astaci (Schikora, 1906) on mortality and growth of marbled crayfish Procambarus virginalis (Lyko, 2017)
• Author: Mara Vukelić
• Mentor: Sandra Hudina (mentor)
• Committee member: Sandra Hudina (predsjednik povjerenstva)
• Committee member: Ivana Maguire (član povjerenstva)
• Committee member: Ivan Čanjevac (član povjerenstva)
• Committee member: Blanka Cvetko Tešović (član povjerenstva)
• Committee member: Kristina Pikelj (član povjerenstva)
• Granter: University of Zagreb; Faculty of Science; (Department of Biology); Zagreb
• Defense date and country: 2021-09-21, Croatia
• Scientific / art field, discipline and subdiscipline: NATURAL SCIENCES; Biology

Abstract

Mramorni rak (Procambarus virginalis, Lyko 2017) je invazivna strana vrsta slatkovodnog raka u Hrvatskoj i svijetu. Predstavlja prijetnju autohtonim vrstama rakova jer je mogući vektor širenja patogena Aphanomyces astaci, Schikora, 1906, uzročnika bolesti račje kuge, koja je smrtonosna za autohtone vrste. Iako ovaj patogen ne uzrokuje značajnu smrtnost kod mramornih rakova, obrana od njega zahtijeva ulaganje energije u imunosni sustav što ograničava njezinu dostupnost za procese kao što su rast i razmnožavanje. Cilj istraživanja je bio ispitati kako opetovano zaražavanje juvenilnih jedinki mramornog raka patogenom A. astaci utječe na njihov prirast dužine i težine. Prvi dio istraživanja sastojao se od uzgoja patogena i zaražavanja manjeg broja juvenilnih jedinki različitim koncentracijama zoospora kako bi se utvrdile optimalne (subletalne) koncentracije za daljnje zaražavanje. U drugom dijelu zaražavanje je provedeno na većem broju jedinki, te su analizirane razlike u prirastu dužine i težine između kontrolne skupine i dvije skupine zaražavane odabranim koncentracijama zoospora. Po završetku eksperimenta, jedinke su usmrćene i iz kutikule i uropoda im je izolirana DNA u čijim uzorcima se provjeravala prisutnost patogena. Rezultati pokazuju da zaražavanje subletalnim koncentracijama patogena ima značajan utjecaj na prirast dužine i težine kod mramornih rakova, te ukazuju da postoji kompromis između ulaganja energije u rast i imunosni sustav kod ove vrste.

Abstract (english)

Marbled crayfish (Procambarus virginalis, Lyko 2017) is an emerging invasive alien species in Croatia and globally. It threatens native species of crayfish because it is carrier of pathogen Aphanomyces astaci, Schikora 1906, the causative agent of crayfish plague which is a highly lethal disease for native crayfish. Although marbled crayfish is generally resistant to crayfish plague, defence from it requires investment of energy in immune system. This consequently leads to trade-offs with other processes like growth and reproduction. The main goal of this research was to determine whether repeated infection of juvenile marbled crayfish with pathogen A. astaci affects their growth rate. In the first part of the research, optimal (sublethal) concentrations for further infections were determined. In the second part, infection trials using two different zoospore concentrations were performed repeatedly on a higher number of individuals and differences in growth rates were compared between control group and two experimental groups. At the end of the experiment, crayfish were killed and DNA was isolated from cuticle and uropods and tested for the presence of A. astaci by PCR. Results showed that pathogen infection had significant effect on growth rate of marbled crayfish which indicates that trade-offs between energy investment in growth and immune response occur in this species.

• Keywords: kompromis; imunosni odgovor; prirast; koncentracija zoospora; račja kuga
• Keywords (english): trade-off; immune response; growth; zoospore concentration; crayfish plague
• Language: croatian
• URN:NBN: urn:nbn:hr:217:118133
• Study programme: Title: Environmental Sciences; Study programme type: university; Study level: undergraduate; Academic / professional title: sveučilišni/a prvostupnik/prvostupnica (baccalaureus/baccalaurea) struke znanosti o okolišu (sveučilišni/a prvostupnik/prvostupnica (baccalaureus/baccalaurea) struke znanosti o okolišu)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Open access; Embargo expiration date: 2022-09-21
• Created on: 2021-09-29 11:12:07