Unusual Localization of Pennella Sp. in Swordfish (Xiphias gladius) Hearts
by
, , , , ,
Davide Mugetti
1,†
,
Elena Colombino
2,†, 
Vasco Menconi
1,*
,
Fulvio Garibaldi
3,
Walter Mignone
1,
Andrea Gustinelli
4,
Marino Prearo
1
,
Franco Guarda
2 and
Maria Teresa Capucchio
2 1
Istituto Zooprofilattico Sperimentale del Piemonte, Liguria e Valle d’Aosta, Via Bologna 148, 10154 Torino, Italy
2
Department of Veterinary Sciences, University of Turin, Largo P. Braccini 2, 10095 Torino, Italy
3
Department of Earth Sciences, Environmental and Life, University of Genova, c.so Europa 26, 16100 Genova, Italy
4
Department of Veterinary Medical Sciences, Alma Mater Studiorum University of Bologna, via Tolara di Sopra 50, 40064 Ozzano Emilia, Italy
*
Author to whom correspondence should be addressed.
†
Equally contribution.
Animals 2021, 11(6), 1757; https://doi.org/10.3390/ani11061757
Submission received: 26 April 2021
/
Revised: 9 June 2021
/
Accepted: 10 June 2021
/
Published: 11 June 2021
(This article belongs to the Special Issue Infectious Diseases and Zoonoses of Wild Marine Animals)
Simple Summary
Copepods of the genus Pennella are parasites of marine aquatic organisms (e.g., cephalopods, pelagic fish, cetaceans). They can infest fish of economic interest, including tuna and swordfish. The infestation of Pennella sp. in fish creates problems of food safety and fish marketing. Generally, these copepods penetrate the host’s muscle, without damaging internal organs. Here, we report on Pennella sp. infestation in swordfish heart muscle. The severity of the cardiac lesions we observed suggests that parasites of the genus Pennella pose a concern for food safety as well as animal health.
Abstract
The genus Pennella comprises hematophagous parasites of marine aquatic species, including cephalopods, marine mammals, and pelagic fish. Nine species have been officially included in the genus Pennella plus another six species inquirendae. They are most often found in the host’s musculature, without penetrating internal organs. For the present study, 83 hearts from swordfish (Xiphias gladius) caught in the Mediterranean Sea were sampled and immediately fixed in formalin for histopathological analysis. In total, 10 (12.05%) hearts were found to be parasitized by copepods of the genus Pennella. Macroscopically, there was mild-to-severe fibrinous pericarditis with atrial wall thickening and multiple parasitic nodules. Histologically, the parasitic nodules were surrounded by an inflammatory-necrotizing reaction. Parasitic infestation by Pennella spp. is common in pelagic fish and in swordfish, in particular. Here, however, we report atypical cardiac localization. A future area of focus is the evaluation of cardiac Pennella spp. infestation by histopathology and genetic identification of the parasites.
