Journal of Threatened Taxa | | 26 September 2022 | 14(9): 21900–21902



ISSN 0974-7907 (Online) | ISSN 0974-7893 (Print)

#5870 | Received 14 March 2020 | Final received 19 July 2022 | Finally accepted 20 September 2022



Visceral tetrathyridiosis Mesocestoides sp. (Cestoda: Cyclophyllidea) in a wild Barn Owl Tyto alba - a first report and new host record


P.G. Vimalraj 1  & A. Latchumikanthan 2


1 Sridhar Nagar, Ariyankuppam, Pondicherry 605007, India.

2 VUTRC, Tamil Nadu Veterinary and Animal Sciences University, Madhavaram Milk Colony, Chennai, Tamil Nadu 605602, India.

1 (corresponding author), 2




Editor: Bahar Baviskar, Wild-CER, Nagpur, India.        Date of publication: 26 September 2022 (online & print)


Citation: Vimalraj, P.G. & A. Latchumikanthan (2022). Visceral tetrathyridiosis Mesocestoides sp. (Cestoda: Cyclophyllidea) in a wild Barn Owl Tyto alba - a first report and new host record. Journal of Threatened Taxa 14(9): 21900–21902.


Copyright: © Vimalraj & Latchumikanthan 2022. Creative Commons Attribution 4.0 International License.  JoTT allows unrestricted use, reproduction, and distribution of this article in any medium by providing adequate credit to the author(s) and the source of publication.


Funding: None.


Competing interests: The authors declare no competing interests.


Acknowledgements: Authors would like to thanks Dr. Karrie Rose DVM, DVSc, Taronga Conservation Society Australia, NSW and Dr. Allan Pessier, DVM, clinical associate professor Washington Animal Disease Diagnostic Laboratory, Washington State University for the scientific cooperation and analysis and other fellow veterinarians.



Mesocestoides sp. is most commonly recorded in all parts of the world (Soulsby 1982) except Australia (Bradley et al. 2018) and this is probably the first record from India. Incidence depends on the species and the region and the disease caused by Mesocestoides sp. tapeworms is called as mesocestoidosis or mesocestoidiasis. Predilection site of adult Mesocestoides sp. tapeworms is the small intestine.

Tapeworms of the genus Mesocestoides sp. require three hosts. The primary definitive host are carnivorous mammals or birds of prey and it does not affect cattle, sheep, goats, swine or horses (Padgett & Boyce 2004). Tetrathyridium is a second stage larvae affecting vertebrate (second intermediate host) and the first stage larvae (metacestode) of first intermediate host is unknown but believed to be an coprophagous arthropod (Brigitte 1991). Mesocestoides species can live in a wide range of hosts, but are particularly widespread in carnivores (Barker et al. 1993; Tenora 2004; David et al. 2011).

Tetrathyridium attached to internal organs were torn loose or cut free and fixed in histo-pathological examinations in 10% neutral-buffered formalin. During necropsy, the encapsulated tetrathyridium were searched throughout the body with a bright LED light source. Formalin fixed tissues were processed by routine paraffin embedding method and 4-μm-thick sections mounted and stained with hematoxylin and eosin (HE). The tissues samples were examined under light microscope. (Rifki et al. 2005; Karl et al. 2016).

Microscopic examination of the tissue samples taken from the liver and lung revealed chronic multiple pyogranuloma due to infestation by Mesocestoides sp. Individual larvae (around six number) were different in shape with convoluted borders. Thick eosinophilic cuticle lined larvae resemble a single layer of cells. The remaining body of the parasite was composed of a loose mesenchymal network with widely scattered parenchymal and muscle cells. Numerous clear vesicles/ refractile bodies namely calcareous corpuscles, round to oval in shape, were observed within the stroma of the parasite. Mineralized areas were seen in some of the old lesions (Soulsby 1982; McAllister 2014; McAllister et al. 2018).

Tetrathyridia in the liver parenchyma were surrounded by a thick mantle of inflammatory cells and a scant, loose connective tissue. In some lesions, there were small lymphocytic nodules at the periphery. No reactive changes were seen in the visceral peritoneum except in superficial lesions where the inflammation extended to the liver surface. Single tetrathyridia occurred in each nodule.

Tetrathyridium on the pleura surface of the lungs were surrounded by a thin layer of loose connective tissue that appeared to be continuous with the pleura. The inner lining of the capsule was partly lined by flattened epithelial-like cells. There was a mild inflammatory reaction to the tetrathyridia, with infiltration of a few macrophages, lymphocytes, and plasma cells. In all lesions examined, tetrathyridia were intact and showed no evidence of degeneration.

We conclude that, Tetrathyridium has been reported in various vertebrate hosts, including wild and domestic animals like birds, snakes, frogs, and rodents (Soulsby 1982; Frank 1991; McAllister et al. 2017) but this is the first record from Barn Owl. Prey species were more prone to risk due to hunting or scavenging on small vertebrates infected with tetrathyridia and detailed molecular discrimination (Skirnisson et al. 2016) within the species to be studied. There are no real effective preventative measures that prevent Mesocestoides tapeworm infection. Effective prevention and control can be achieved with numerous anthelmintic products in domestic animals but less possible in wildlife (Ivan et al. 2004; Ubelaker et al. 2014). Biological control of Mesocestoides is so far not feasible and there are no reports on resistance of Mesocestoides tapeworms to anthelmintics.



For images – click here for full PDF




Barker, I.K., A. Van Dreumel & N. Palmer (1993). Infectious and Parasitic Diseases of the Gastrointestinal Tract, pp. 187–292. In: Pathology of Domestic Animals, 4th edition. Vol. 2. Academic Press, San Diego.

Bradley, W.K., J.T. Nicole, V.T. Vasyl, R.S. Taylor, R. Dale & F. Alan (2018). Mesocestoides sp. in Wild Northern Bobwhite (Colinus virginianus) and Scaled Quail (Callipepla squamata). Journal of Wildlife Diseases 54(3): 612–616.

Brigitte, L.F. (1991). One or two intermediate hosts in the life cycle of Mesocestoides (Cyclophyllidea, Mesocestoididae)? Parasitology Research 77(8): 726–728.

David, B.C., T.G.P.Maria & V.F. Màrius (2011). Normal and Aberrant Mesocestoides Tetrathyridia from Crocidura Spp. (Soricimorpha) in Corsica and Spain. The Journal of Parasitology 97(5): 915–919.

Frank, J.E. (1991).The Proliferative Tetrathyridium of Mesocestoides vogae sp. n.(Cestoda). Journal Helminthological Society of Washington 58(2): 181–185.

Ivan, L., D.O. Peter, B.G. Boyko & S. Marta (2004). First record of metacestodes of Mesocestoides sp. in the Common Starling (Sturnus vulgaris) in Europe, with an 18S rDNA characterisation of the isolate. Folia Parasitologica 51: 45–49.

Karl, S., J. Damien, F. Hubert & K.N. Ólafur(2016). Occurrence of Mesocestoides canislagopodis (Rudolphi, 1810) (Krabbe, 1865) in mammals and birds in Iceland
and its molecular discrimination within the Mesocestoides species complex. Parasitology Research 115(7): 2597–2607.

Karl, S.,G.S. Ólöf & K.N. Ólafur(2016). Morphological characteristics of Mesocestoides canislagopodis (Krabbe 1865) tetrathyridia found in rock ptarmigan (Lagopus muta) in Iceland. Parasitology Research 115(8): 3099–3106.

McAllister, C.T., V.T. Vasyl & B.C. David (2018).Morphological and Molecular Characterization of Post-Larval Pre-Tetrathyridia of Mesocestoides sp. (Cestoda: Cyclophyllidea) from Ground Skink, Scincella lateralis (Sauria: Scincidae), from Southeastern Oklahoma. Journal of Parasitology 104(3): 246–253.

McAllister, C.T., E.T. Stanley & B.C. David (2017). First Report of Mesocestoides sp. Tetrathyridia (Cestoda: Cyclophyllidea) from the American Bullfrog, Rana catesbeiana (Anura: Ranidae). Proceedings of the Oklahoma Academy Science 97: 15–20.

McAllister, C.T., M.B. Connior & S.E. Trauth (2014). New Host Records for Mesocestoides sp. Tetrathyridia (Cestoidea: Cyclophyllidea) in Anurans (Bufonidae, Ranidae) from Arkansas, with a summary of north american amphibian hosts. Journal of the Arkansas Academy of Science 68 (29): 158–162.

Padgett, K.A. & W.M. Boyce(2004). Life-history studies on two molecular strains of Mesocestoides (Cestoda: Mesocestoididae): identification of sylvatic hosts and infectivity of immature life stages. Journal of Parasitology 90: 108–113.

Rifki, H., O. Eser, G. Tolga, O. Semih, T. Recai, T. Sait & O. Sule (2005). Peritoneal tetrathyridiosis in a Siamese cat - a case report. Veterinarski arhiv 75(5): 453–458.

Soulsby, E.J.L. (1982). Cestodes, pp. 87–136. In: Helminths, Arthropods and Protozoa of Domesticated Animals. 7th edition, Bailliére Tindall. London, Philadelphia, 809 pp.

Tenora, K. (2004).  Notes to MesocestoidesVaillant, 1863 (Cestoda) and Findings of Mesocestoides sp. Parasitizing Canisfamiliaris (Carnivora) in the Czech Republic F. Acta  Universitatis Agriculturate Et Silviculture Mendelianae Brunensis Sbornik Mendelovy Zemedelske A Lesnicke University V Brno., 25–34 pp.

Ubelaker, J.E., N. Abdullah, A. Mouha, R. Ananadampillair, C. Emigh &S.L. Gardner (2014).”Natural Infections of Tetrathyridia of Mesocestoides Species in Deer Mice, Peromyscus maniculatus, from New Mexico”. The Southwestern Naturalist 59(3): 404–406.