This study analyzed 74 sheep flocks to determine if the presence of goats is a risk factor for parasitic infections in sheep. Flocks with mixed sheep-goat management had higher rates of protostrongylid nematodes, gastrointestinal nematodes, Dictyocaulus filaria, and Eimeria spp. compared to flocks without goats. No association was found for Fasciola hepatica, Dicrocoelium, Paramphistomidae, or Moniezia. The results indicate that mixed sheep-goat management should be considered a risk factor in statistical analyses of parasitic infections in sheep.

1. INVESAGA - USC
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XVIII Congreso de la Sociedad
Española de Parasitología
The goat as a risk factor for parasitic infections in
ovine flocks
López, C.M., Panadero, R., Díaz, P., Pérez, A., Cabanelas,
E., Díez-Baños, P., Morrondo, P.

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Sheep-goat contact
● 30% flocks
● Risk factor?
● VM (Lago et al., 2012)
● Protostrongilidae (López et al., 2011)
INTRODUCTION

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MATERIAL AND METHODS
Sheep-goat contact
● 74 flocks
● 2,093 sheep
– 468 mixed manage with goats
– 1,625 manage without goats
● Flotation, sedimentation and migration
● R - cc() function – epicalc package

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RESULTS
● Protostrongylidae
χ2= 21.690; P<0,001
goats
Prot. no yes total
neg 1466 385 1851
pos 159 83 242
total 1625 468 2093

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RESULTS
● Gastrointestinal
nematodes
χ2= 24.910; P<0,001
goats
GI no yes total
neg 582 99 681
pos 933 300 1233
total 1515 399 1914

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RESULTS
● Dictyocaulus filaria
χ2= 12.312; P<0,001
goats
D.filaria no yes total
neg 1473 397 1870
pos 152 71 223
total 1625 468 2093

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RESULTS
● Eimeria spp
χ2= 12.312; P<0,001
goats
Eimeria no yes total
neg 422 77 681
pos 1093 322 1233
total 1515 399 1914

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RESULTS
No association
● Fasciola hepatica (104 positive; OR 1.01)
● Dicrocoelium (14 positive)
● Paramphistomidae (12 positive)
● Moniezia (96 positive; OR 1.02)

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IN FACT ...
● Association ≠ causality
– Biological explanation
● Confouding variable
– Multivariate analysis
● but...

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CONCLUSION
Mixed management sheep-goat must be
introduced as a risk factor in statistical
analysis in sheep infection studies

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THANKS
Supported by the research project PGIDIT06RAG26101PR
and a grant for Consolidating and Structuring Competitive
Research Groups (Xunta de Galicia CN2012/326)
References:
López et al. (2011). Vet. Parasitol. 178, 108-114.
Lago et al. (2012). Prev.Vet.Med. 103, 163-169.

12. INVESAGA - USC
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XVIII Congreso de la Sociedad
Española de Parasitología
The goat as a risk factor for parasitic infections in
ovine flocks
López, C.M., Panadero, R., Díaz, P., Pérez, A., Cabanelas,
E., Díez-Baños, P., Morrondo, P.