Plavoperajna tuna Thunnus thynnus (Teleostea, Scombridae) vrlo je vrijedan proizvod zbog mesa pogodnog za konzerviranje a po sastavu bjelančevina jako srodnog bjelančevinama čovjeka. Stoga je ova vrsta ribe jedan od glavnih hrvatskih izvoznih proizvoda, bilo u svježem, smrznutom ili prerađenom obliku, a kao takav podliježe ocjeni kakvoće sirovina i prerađevina. Ključno, ali često zanemarivano mjesto, pri ocjeni kakvoće ribe imaju nametnici, budući da mehanički ili postmortalno enzimatskim djelovanjem umanjuju kakvoću namirnice (primjerice pripadnici rodova Kudoa, Microsporidia, Didymocystis) ili neposredno ugrožavaju čovjekovo zdravlje (Anisakis sp.). Parazitološkom pretragom uzgojene tune, izoliran je račić veslonožac Pennella filosa (Pennellidae, Copepoda). Iako se radi o nametniku koji nije štetan po zdravlje čovjeka, njegov način prihvaćanja duboko u mišićne slojeve najcjenjenijih dijelova trupa tune, može uzrokovati lokalizirane procese s nekrozama, zbog kojih se meso ocjenjuje neprikladnim za ljudsku konzumaciju.Blufin tuna Thunnus thynnus (Teleostea, Scombridae) represents very valuable product because of its appreciated meat quality, adequate for conservation and similar in protein content and quality to human proteins. This scombrid is one of the main Croatian export products, either in fresh, frozen or processed form, and therefore, both raw material and products are subjected to quality assessment. The key feature, even though often neglected, in the process of quality assessment belongs to parasites, because they are able to reduce the quality of meat by mechanical and post-mortem enzymatic changes (member of the genera Kudoa, Microsporidia, Didymocystis) or directly endanger the human health (Anisakis sp.). During the parasitological examination of reared tuna, copepodid crustacean Pennella filosa (Pennellidae, Copepoda) was isolated. Even though this parasite does not present risk to human health, its deep attachment in the muscular layers of the most valuable parts of tuna trunks can cause localised processes with necrosis, resulting in reduced quality and thus becoming inappropriate for human consumption
