Histological Change of Aquatic Animals by Parasitic Infection

Abstract

Histopathology-Reviews and Recent Advances 154 ectoparasites are the most common parasites encountered in cultured fish [3]. They are also frequently found in wild fish [4]. Ciliates and flagellates feed on the most superficial skin layer [4]. Parasites cause a reactive hyperplasia of the epithelium and increased mucus production. Hyperplasia appears as a cloundiness to the skin and leads to hypoxia if occur on the gills [4]. Microspora are intracellular and affect a wide variety of vertebrates and invertebrates, Myxosporea are largely intercellular and infect mainly fish [5]. 2.1. Phylum Rhizopoda (amoeba) Amoeba can infect on the external surface such as gill, skin and internal organ as intestine. Paramoeba pemaquidensis has caused chronic mortality [4]. This parasite causes proliferative gill lesions. Histopathological change includes focal lamellar hypertrophy with epithelial hyperplasia and metaplasia [4]. Neoparamoeba perurans causes amoebic gill disease (AGD) [6]. This parasite affects some species of fish farmed in the marine environment such as Atlantic salmon [7]. The gills of infected fish are pale, multifocal with diffused white AGD-like lesions. Histological changes in the gills are characterized by hyperplasia of epithelial like cells across the gill filaments. This resulted in the fusion of lamellae and the development of round to oval interlamellar vesicles. Hyperplasia of mucous cells are also observed in the gills [6]. 2.2. Phylum Mastigophora (flagellated protozoa) Aquatic parasites in this subphylum separated in two classes; Phytomastigophora and Zoomastigophora Phytomastigophora contain chloroplasts in their cytoplasm [2]. Common type of this group was dinoflagellate parasites Amyloodinium sp. and Piscinoodinium sp. [2]. Amyloodinium sp. and Piscinoodinium sp. cause necrotic dermatitis to their host. Amyloodinium ocellatum is marine fish parasites that can infect both elasmobranchs and teleosts [4]. They attach to the host's epithelium by rhizoids (root-like structures) and feed on the host [4]. The gills are the primary site of infection. Heavy infestations can cause gill hyperplasia which include epithelium to severe hyperplasia of the entire gill filament, inflammation, hemorrhage and necrosis. In freshwater, Piscinoodinium is reported, histopathological changes are similar to Amyloodinium sp. Filament degeneration and necrosis may also occur [4]. Zoomastigophora do not contain chloroplasts in their cytoplasm [2]. Three orders; Kinetoplastida, Retortamonodida and Diplomonadida are usually reported as fish parasites [2]. Parasites of order Kinetoplastida have one or two flagella such as Cryptobia sp. [2]. Cryptobia spp. are reported to invade the gastric epithelium of European cyprinids and flounders, they may cause gastric dilation, lesions include submucosal granuloma, gastric perforation, peritonitis and full thickness necrosis of the body wall musculature (Ferguson, 1989).

Possible mechanism of host manipulation resulting from a diel behaviour pattern of eye-dwelling parasites?

“…Sections were stained with haematoxylin and eosin and examined by light microscopy. The qualitative analysis was performed by comparing infected and uninfected tissue, and looking for damage characteristic of that was found in Grobbelaar et al (2015) and described in Bullard and Overstreet (2008) and Purivirojkul (2012). The number of metacercariae per eye was estimated via the histological slides.…”

Antiparasitic and Antibacterial Functionality of Essential Oils: An Alternative Approach for Sustainable Aquaculture

“…Euclinostomum heterostomum is parasitic trematodes and very common in Europe, Asia, and Africa [ 88 ]. It infects muscular tissues and kidneys of freshwater fish [ 88 , 89 ].…”

“…Euclinostomum heterostomum is parasitic trematodes and very common in Europe, Asia, and Africa [ 88 ]. It infects muscular tissues and kidneys of freshwater fish [ 88 , 89 ]. Verbesina alternifolia and Mentha piperita EOs could act on E. Heterostomum in high doses and for a long time [ 90 ] ( Table 2 ).…”

Utilização De Alimentadores De Auto-Demanda: Uma Revisão E Potencial Uso Para Peixes Amazônicos

“…Esses parasitos infectam vários tecidos e órgãos dos peixes como estômago, intestino, fígado, gônadas, mesentério, cavidade corporal, entre outros (Moravec, 1998;Thatcher, 2006;Eiras et al, 2010). Alterações histopatológicas provocadas por nematoides são destruição e atrofia da mucosa intestinal, necrose e degeneração do tecido intestinal, e podem também, dependendo da espécie de nematoide, causar danos hepáticos (Purivirojkul, 2012;Rivadeneyra et al, 2020).…”

“…O ciclo de vida desse grupo é indireto, sendo necessário um artrópode como hospedeiro intermediário e um vertebrado como hospedeiro definitivo (Santos et al, 2013). Este parasito é provido de uma probóscide na região anterior, que ao se prender na parede intestinal do hospedeiro causa danos significativos como inflamação, formação de tecido granular, proliferação de tecido conjuntivo e mobilização de células como neutrófilos, linfócitos e fibroblastos, formando uma camada fibrosa composta, junto com os mastócitos locais, no tecido inflamado (Wanstall et al, 1986;Purivirojkul, 2012;Matos et al, 2017).…”