Prevalence and burden of helminths in laying hens kept in free range systems F. Kaufmann and M. Gauly Department of Animal Science, University of Goettingen
Introduction
Development of laying hen husbandry systems in Germany (%) % 100 cage deep litter free range small group 80 85,4 80,8 73,2 66,1 60 40 33,8 20 0 14,6 9,4 6,8 7,8 9,8 17 14 12,7 15,3 2001 2003 2005 2007 1,5 ZMP, 2008
Problems Flock size Cannibalism Contact with litter and faeces Increased risk of infections for various pathogens Exposure to unfavorable climatic conditions Difficult flock and animal control
Consequences on health, vitality and behaviour Increased: - bacterial, viral and parasitic infections - maladaptive behaviour: featherpecking cannibalism Mortality (Permin et al., 1999; Inrungu et al., 2004; Gauly et al., 2007; Fossum et al., 2009)
Consequences on health, vitality and behaviour Increased: - bacterial, viral and parasitic infections - maladaptive behaviour: featherpecking cannibalism Mortality (Permin et al., 1999; Inrungu et al., 2004; Gauly et al., 2007; Fossum et al., 2009)
Economy Hygiene Consumer Animal welfare
Objective Estimate the importance of parasitic diseases in free range systems development of preventive strategies Estimate prevalence and burden of helminths in free range layers in Germany
Animals, Materials and Methods
Animals 144 laying hens: Lohmann Brown (n = 39) ISA Brown (n = 49) Tetra Brown (n = 45) Bovans Black (n = 6) Lohmann Tradition (n = 5) 11 free range farms (Ø 13 hens per farm, randomly collected) Collected at different times of laying period
Parasitological examinations According to W.A.A.V.P (Yazwinski et al., 2003) Trachea Esophagus Proventriculus Ventriculus Small intestine Caecal tubes
Statistical analyses Prevalence...(p %) = n / N Mean worm burden (WB ± SD) Genotype differences were calculated using generel linear model with effect of breed within farm
Results
Species found Nematodes: - Ascaridia galli - Heterakis gallinarum - Capillaria spp. - Acuaria hamulosa Cestodes - Raillietina cesticillus - Hymenolepis cantaniana - Choanotaenia infundibulum
Prevalence (%) of infections with adult nematodes in 144 laying hens Prevalence (%) 100 90 80 70 60 50 40 30 20 10 0 66,6 84 75,1 1,4 92,4 Ascaridia galli Heterakis gallinarum Capillaria spp. Acuaria hamulosa Total
Mean worm burden of infections with adult nematodes in 144 laying hens 160 140 135,7 Mean worm burden 120 100 80 60 40 20 0 16 97,6 45,7 1 Ascaridia galli Heterakis gallinarum Capillaria spp. Acuaria hamulosa Total
Prevalence (%) of infections with cestodes in 144 laying hens 30 25 24,3 25,7 Prevalence (%) 20 15 10 5 2,1 2,8 0 Raillietina cesticillus Hymenolepis cantaniana Choanotaenia infundib ulum Total
Mean worm burden of infections with cestodes in 144 laying hens Mean worm burden 50 45 40 35 30 25 20 15 10 5 0 41,3 11,3 26,8 42,9 Raillietina cesticillus Hymenolepis cantaniana Choanotaenia infundib ulum Total
Genotype differences 250 a Total mean worm burden 200 150 100 50 b b 0 a; b p < 0.0001 TETRA ISA LB
Conclusion Broad spectrum of helminths were found High prevalences majority of hens are subclinically infected Economic losses! Genetic differences (no. of animals low) parasite resistance as breeding aim for the future!?
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