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Metastrongylus spp. infection in a farmed wild boar (Sus scrofa) in Finland

  • 1,
  • 2,
  • 3,
  • 3 and
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Acta Veterinaria Scandinavica201052 (Suppl 1) :S21

  • Published:


  • Faecal Sample
  • Wild Boar
  • Intermediate Host
  • Osteomalacia
  • Poor Nutritional Condition


Metastrongylus spp. (Nematoda, Metastrongylidae) are lung worms of swine and occur worldwide. Species in the family include M. apri, M. pudendotectus, M. asymmetricus, and M. salmi. Earth worms are intermediate hosts and pigs get infected when eating earth worms.

In Finland wild boar farming began in the 1980s and now there are over hundred farms and over 2000 wild boars in different parts of the country. This case report is part of a study aiming to get more information about the diseases that occur in the farmed wild boar population in Finland.

Lungworms were detected in an eight month old farmed wild boar sent for necropsy from a farm situated in eastern Finland. In the group of 25 animals of about the same age, the farmer had noticed poor growth and gait abnormalities. He submitted two euthanized boars (A and B) for necropsy. A routine necropsy was performed and tissue samples were collected for histopathology, bacteriology and parasitology.

The boar A was in a poor nutritional condition. The lungs were slightly mottled, but otherwise normally inflated. Large numbers of white thread like nematodes were detected in the bronchi (Fig. 1.). Bones were soft. In the faecal sample, 7500 EPG Metastrongylus spp. eggs were detected with flotation (Fig. 2.). The boar B was in a moderate nutritional condition. No lung worms were detected. The main pathological diagnosis of both was osteomalacia due to deficiency of mineral feeding. However, the the poor nutritional condition of the boar A infected with lung worms was possibly partly due to the lung worm infection. Four additional faecal samples were sent from remaining boars from the farm and two of them were also positive for Metastrongylu s spp. eggs (100 and 200 EGP).
Figure 1
Figure 1

Cross section of Metastrongylus spp. in the lung.

Figure 2
Figure 2

Metastrongylus spp. egg with a larva inside.

In Finland Metastrongylus spp. has occurred sporadically in pigs decades ago in southeastern parts of the country [unpublished, Nikander, [1]. It was not detected in domestic pigs in a large study done in all Nordic countries in 1980’s [1]. It was also not found in a study of Danish organic swine herds [2]. In natural wild boar in many countries this parasite is common [36]. In the modern pig industry this infection seems to have been disappeared, because there is no contact with the intermediate host, the earth worms. However, in the farmed wild boar, and in situations where pigs are kept outdoors, Metastrongylus spp. should be considered as a possible cause of poor growth and respiratory signs.

Authors’ Affiliations

Veterinary Bacteriology Research Unit, Finnish Food Safety Authority Evira, Kuopio, Finland
Fish and Wildlife Health Research Unit, Finnish Food Safety Authority Evira, Oulu, Finland
Department of Production Animal Health, University of Helsinki, Pohjoinen pikatie 800, 04930 Saarentaus, Finland


  1. Roepstorff A, Nilsson O, Oksanen A, Gjerde B, Richter SH, Örtenberg E, Christensson D, Martinsson KB, Bartlett PC, Nansen P: Intestinal parasites in swine in the Nordic countries, prevalence and geographical distribution. Vet Parasitol. 1998, 76: 305-319. 10.1016/S0304-4017(97)00223-9.View ArticlePubMedGoogle Scholar
  2. Carstensen L, Vaarts M, Roepstorff A: Helminth infections in Danish organic swine herds. Vet Parasitol. 2002, 106: 253-264. 10.1016/S0304-4017(02)00080-8.View ArticlePubMedGoogle Scholar
  3. Järvis T, Kapel Ch, Moks E, Talvik H, Mägi E: Helminths of wild boar in the isolated population close to the northern border of its habitat area. Vet Parasitol. 2007, 150: 366-369. 10.1016/j.vetpar.2007.09.015.View ArticlePubMedGoogle Scholar
  4. Morita T, Haruta K, Shibata-Haruta A, Kanda E, Imai S, Ike K: Lung worms of wild boars in the western region of Tokyo, Japan. J Vet Med Sci. 2007, 69: 417-420. 10.1292/jvms.69.417.View ArticlePubMedGoogle Scholar
  5. de-la-Muela N, Hernandez-de-Lujan S, Ferre I: Helminths of wild boar in Spain. J Wildl Dis. 2001, 37: 840-843.View ArticlePubMedGoogle Scholar
  6. Barutzki D, Schoierer R, Gothe R: Helminth infections in wild boars in enclosures in southern Germany: species spectrum and infection frequency. Tierarztl Prax. 1990, 18: 529-534.PubMedGoogle Scholar


© Syrjälä et al; licensee BioMed Central Ltd. 2010

This article is published under license to BioMed Central Ltd.