Prevalence and magnitude of gastrointestinal helminth infections in cage-free laying chickens in Australia

Anwar Shifaw; Teka Feyera; Brendan Sharpe; Timothy Elliott; Stephen W Walkden-Brown; Isabelle Ruhnke

doi:10.1016/j.vprsr.2022.100819

Prevalence and magnitude of gastrointestinal helminth infections in cage-free laying chickens in Australia

Vet Parasitol Reg Stud Reports. 2023 Jan:37:100819. doi: 10.1016/j.vprsr.2022.100819. Epub 2022 Dec 16.

Authors

Anwar Shifaw¹, Teka Feyera², Brendan Sharpe³, Timothy Elliott⁴, Stephen W Walkden-Brown⁴, Isabelle Ruhnke⁴

Affiliations

¹ Animal Science, School of Environmental and Rural Science, University of New England, Armidale, NSW 2351, Australia. Electronic address: ayesuf@myune.edu.au.
² Animal Science, School of Environmental and Rural Science, University of New England, Armidale, NSW 2351, Australia; Department of Veterinary Clinical Studies, College of Veterinary Medicine, Jigjiga University, Jigjiga, P. O. Box 1020, Ethiopia.
³ Invetus Pty Ltd, Armidale, NSW 2350, Australia.
⁴ Animal Science, School of Environmental and Rural Science, University of New England, Armidale, NSW 2351, Australia.

PMID: 36623907
DOI: 10.1016/j.vprsr.2022.100819

Abstract

Helminth infections have been re-emerging with the growing popularity of free-range and floor-based chicken production systems. The aim of this study was to determine the prevalence and worm burdens of intestinal helminth infection in cage-free laying chickens in Australia. In an online survey about worm prevalence, a high proportion of respondents reported the detection of Ascaridia galli (77%), followed by tapeworms (69%) and caecal worms (Heterakis gallinarum) (62%), whereas fewer respondents (23%) reported the presence of hair worms (Capillaria spp.) in their flocks. Total worm recovery from 407 laying hens on four farms found that 92.1% of hens harboured one or more helminth parasite with a prevalence of 73 to 100% across farms. Mixed infections were common with 79% of hens harbouring two or more helminth species. The prevalence of nematode species H. gallinarum, A. galli and Capillaria spp. was 87, 82 and 35% respectively. Five cestode species were found with a low individual chicken prevalence (Raillietina tetragona 4.7%, Raillietina echinobothrida 3.2%, Raillietina cesticillus 5.2%, Choanotaenia infundibulum 4.4%, and Hymenolepis cantaniana 4.4%). The hens harboured an average of 71 worms with H. gallinarum having the highest mean burden (45.5 worms/hen) followed by A. galli (22.0 worms/hen), Capillaria spp. (2.7 worms/hen) and cestodes (0.8 worms/hen). The sex ratio (female:male worms) was 1.38:1 for A. galli, and 1.77:1 for H. gallinarum. There was a strong positive correlation between A. galli female worm count and excreta egg count (EECs) (r_s = 0.94, P < 0.0001) and also between total nematode worm count and EEC (r_s = 0.82, P < 0.0001) in individual hens. When investigating intestinal excreta (n = 10) and caecal excreta (n = 10) of 16 chicken flocks the prevalence of infection with ascarid worms in intestinal and caecal excreta was 71 and 78% respectively and 27% prevalence of Capillaria spp. in intestinal excreta with mean EECs of 407, 404, and 18 eggs/g of excreta (EPG), respectively. These results suggest that most chickens kept in free-range or floor production systems are infected with one or more helminth parasite species. Heavy worm infections would likely affect the production performance and welfare of birds with adverse economic impact. Strategic or tactical anthelmintic treatment with effective anthelmintic could reduce this impact.

Keywords: Cestode; Chicken; Egg count; Nematode; Prevalence; Production system; Worm burden; Worm infections.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Animals
Anthelmintics*
Chickens / parasitology
Female
Gastrointestinal Diseases* / veterinary
Helminths*
Male
Nematoda*
Prevalence

Substances

Anthelmintics