Praćenje titra specifičnih protutijela potaknutog autogenim cjepivom protiv APEC sojeva E. coli na roditeljskim farmama teške pasmine kokoši

master's thesis

• Title (english): Monitoring of specific antibody titers induced by autogenous vaccine against APEC strains of E. coli in broiler parent flocks
• Author: Inga Čelebić
• Mentor: Željko Gottstein (mentor)
• Committee member: Danijela Horvatek Tomić (predsjednik povjerenstva)
• Committee member: Željko Gottstein (član povjerenstva)
• Granter: University of Zagreb; Faculty of Veterinary Medicine; Zagreb
• Defense date and country: 2021-11, Croatia
• Scientific / art field, discipline and subdiscipline: BIOMEDICINE AND HEALTHCARE; Veterinary Medicine; Veterinary Public Health and Food Safety

Abstract

APEC strains (Avian pathogenic Escherichia coli) are the main cause of collibacilosis in poultry. They inflict major economic damage by causing high morbidity and mortality in chicks, broilers and laying hens. Also, chicken meat products contaminated with APEC present danger for human health. Appearance of resistant and multiresistant strains as a result of long term, excessive use of antibiotics, has widely limited attainability of effective antimicrobial substances and forced us to search for more effective options for reducing the incidence of collibacilosis and large economical loses caused by it. Production and administration of autogenous vaccines is a very effective method in disease prevention. In this research, microbiological monitoring of the delivered carcasses enabled isolation of E. coli strains in the broiler parent flock farms. After that, typing of the isolates was conducted and an autogenous vaccine was produced for vaccination of pullets and roosters at 9 and 19 weeks of age. For determining specific antibody titre, an ELISA test was made from inactivated antigen used for manufacturing of the vaccine. Results proved a significant titre increase after application of the autogenous vaccine. Application of aluminium hydroxide as adjuvant stimulated fast rise of the titre, but also a constant drop of titre. Oil adjuvant on the other hand stimulates long lasting titre which is double in values in vaccinated flocks compared to unvaccinated older flocks.

Abstract (english)

APEC strains (Avian pathogenic Escherichia coli) are the main cause of collibacilosis in poultry. They inflict major economic damage by causing high morbidity and mortality in chicks, broilers and laying hens. Also, chicken meat products contaminated with APEC present danger for human health. Appearance of resistant and multiresistant strains as a result of long term, excessive use of antibiotics, has widely limited attainability of effective antimicrobial substances and forced us to search for more effective options for reducing the incidence of collibacilosis and large economical loses caused by it. Production and administration of autogenous vaccines is a very effective method in disease prevention. In this research, microbiological monitoring of the delivered carcasses enabled isolation of E. coli strains in the broiler parent flock farms. After that, typing of the isolates was conducted and an autogenous vaccine was produced for vaccination of pullets and roosters at 9 and 19 weeks of age. For determining specific antibody titre, an ELISA test was made from inactivated antigen used for manufacturing of the vaccine. Results proved a significant titre increase after application of the autogenous vaccine. Application of aluminium hydroxide as adjuvant stimulated fast rise of the titre, but also a constant drop of titre. Oil adjuvant on the other hand stimulates long lasting titre which is double in values in vaccinated flocks compared to unvaccinated older flocks.

• Keywords: E. coli; APEC; autogenous vaccine; broiler parent flocks
• Keywords (english): E. coli; APEC; autogenous vaccine; broiler parent flocks
• Language: croatian
• URN:NBN: urn:nbn:hr:178:669266
• Study programme: Title: Veterinary Medicine; Study programme type: university; Study level: integrated undergraduate and graduate; Academic / professional title: doktor/doktorica veterinarske medicine (doktor/doktorica veterinarske medicine)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Open access
• Created on: 2021-12-01 12:39:25