In most aquatic ecosystems, fishes are hosts to parasites and, sometimes, these parasites can affect fish biology. Some of the most dramatic cases occur when fishes are intermediate hosts for larval parasites. For example, fishes in southern California estuaries are host to many parasites. The most common of these parasites, Euhaplorchis californiensis, infects the brain of the killifish Fundul...

The present study was the first attempt to survey the diversity of fish zoonotic parasites in the southern region of Saudi Arabia, particularly the Najran area, from October 2012 to October 2013. Approximately 163 fish representing seven species (two of freshwater fish and five of marine fish) were examined for fish-borne trematode metacercariae using the compression technique, and for zoonotic...

Adult worms of the blood-feeding monogenean parasite Neoheterobothrium hirame, which cause anemia in the Japanese flounder Paralichthys olivaceus, attach to the host fish by embedding their posterior part deeply into the host tissue. To investigate the possibility that cellular responses of the host fish can eliminate N. hirame, flounder were experimentally infected with N. hirame larvae and re...

We assessed mercury contamination of water, sediment, and selected aquatic biota from two lagoons in the Apostle Islands National Lakeshore (southern Lake Superior). These nearshore lagoon systems appear to be mercury-sensitive environments with unusually high rates of production of methylmercury, a highly toxic compound that readily bioaccumulates in aquatic food webs. Concentrations of methyl...

The Magadi tilapia, Alcolapia grahami, a small cichlid fish of Lake Magadi, Kenya lives in one of the most challenging aquatic environments on earth, characterized by very high alkalinity, unusual water chemistry, and extreme O2, ROS, and temperature regimes. In contrast to most fishes which live at temperatures substantially lower than the 36-40 °C of mammals and birds, an isolated population ...

the studies of parasitology was performed on freshwater in farm ponds in isfahan province during the years of 2006- 2008 and in total were fished 150 fish from farm ponds of freshwater fish and dual purpose of agriculture of three regions in isfahan. the fish were 65 cyprinus carpio, 40 hypophthalmichthys molitrix and 45 ctenopharyngodon idella. the samples were taken to laboratory alive and af...

Six blooms of Heterosigma akashiwo (Raphidophyceae) were observed from March 2007 through March 2008 in the Rodrigo de Freitas Lagoon, a semi-confined eutrophic system located in Rio de Janeiro state, southeast Brazil. Vegetative cells of H. akashiwo analysed by optical and electron microscopy showed morphology as described in the literature. The blooms (2.8 × 10(4) to 4 × 10(8) cell.L(-1)) wer...

Intra-specific morphological variation in the indigenous catfish Arius jella (Ariidae) was studied in five estuarine localities in Sri Lanka (Koggala lagoon, Walawe estuary, Garanduwa lagoon, Nilwala estuary and Chilaw lagoon) using morphometric analysis. Five morphometric characteristics describing the shape of the fish were significantly different among some of the locations. Significantly sh...

The Atlantic anchoveta, Cetengraulis edentulus (Cuvier, 1829) is one of the most commercially important fish species in littoral Brazil. present study evaluates parasitic fauna this engraulid from southeastern Brazilian coast. Between October 2019 and March 2020, a total 100 specimens C. Sepetiba Bay, Rio de Janeiro, Brazil (22°57’44”S; 43°52’28”W), were examined. Eighty-five parasitized by at ...

Global warming scenarios combined with political and public awareness have led to increasing funding and research efforts on the measurement and prediction of effects of a changing world on the ecosystems. Fish parasites represent a major part of aquatic biodiversity, and consequently become affected either directly through the environment or indirectly through their respective hosts. On the ba...