Infestation Of Fish Research Articles

Экономический ущерб при лигулезе и смешанных формах гельминтозов, инфестаций рыб на костромском участке Горьковского водохранилища

Экономический ущерб при лигулезе и смешанных формах гельминтозов, инфестаций рыб на костромском участке Горьковского водохранилища

Evaluation of aqueous extract of robusta coffee (Coffea canephora) leaves for controlling Argulus japonicus infestation on common carp seed

Argulus japonicus is common crustacea ectoparasite that infest in freshwater fish. The heavy infestation may trigger other fish pathogen infection which lead to mass mortality. Common carp seed has been known as the most vulnerable host for A. japonicus infestation due to their immature immune system. Generally, A. japonicus infestation could be controlled by chemical pesticides but its long-term use could create a harmful effect on the environment. Therefore, an eco-friendly natural product is needed to replace chemical pesticide. The purpose of this study was to evaluate the effectivity of water extract of robusta coffee leaves to control A. japonicus infestation. Water extract of robusta coffee leaves was obtained from decoction method. The fish were infected with A. japonicus by artificial infestation using cohabitation method. The infected fish were dipped at different concentration 400 (P1), 800 (P2), 1200 (P3) and 1600 ppm (P4) of water extract for 30 minutes. The result presented that the water extract of robusta coffee leaves was effective to control A. japonicus infestation in 1600 ppm. This study revealed that robusta coffee leaves have anti-parasitic activity against A. japonicus. Hence, it can be used as an alternative natural product for controlling A. japonicus infestation in fish.

Argulus elongatus (Branchiura, Argulidae) in fish in the upper São Francisco river, Brazil.

Among 164 fish from the upper São Francisco river, caught in the Três Marias reservoir (18º 12' 59" S; 45º 17' 34" W) or downstream from this reservoir (18º 12' 32" S; 45º 15' 41" W) in 2007, 2008, 2016 and 2017, four specimens of Argulus elongatus Heller, 1857 were found, one specimen per fish, in the following host species: Brycon orthotaenia Günther (two fish parasitized out of 38 examined) and Salminus hilarii Valenciennes (one fish parasitized out of 45 examined) (both in Bryconidae); and Metynnis lippincottianus (Cope) (one fish parasitized out of 81 examined) (Serrasalmidae). This opportunistic ectoparasite deserves attention even in the case of low infestation in fish in a natural water system. This is the first record of a branchiuran species in B.orthotaenia; the host list of A.elongatus is extended through addition of the three fish species examined in this study, and the known Brazilian geographical distribution of this argulid is enlarged to the São Francisco river basin.

Histopathological alterations and parasitic infection in Oreochromis niloticus fish inhabiting the River Nile water.

Histological and parasitic examinations represent an excellent tool for determining the effect of Nile water contamination on fish health status. This paper outlines the effect of sewage, industrial and agricultural drainage water into six selected sites (El-Kanater El-Khyria, El-Qatta, Tamalay, Kafr El-Zayat, Benha and Talkha) at River Nile branches on Oreochromis niloticus fish. Water samples were collected from the investigated area during winter 2019 to assess the status of water by determining some physicochemical characteristics (temperature, electrical conductivity, transparency, pH, oxygen and nutrient salts). Also, histological features for some organs (liver, kidney, and gills) and parasitic infestation in fish were studied. The results revealed that the uncontrolled inputs of wastes altered the water quality of investigated areas leads to the prevalence of the most common parasites genera which infected Oreochromis niloticus health status in the form of histological alteration.

Fish hosts of the freshwater mussel Unio foucauldianus Pallary, 1936

Abstract The life cycle of Unio foucauldianus Pallary, 1936, a critically endangered freshwater mussel species (Bivalvia: Unionida), includes a parasitic phase using fish as hosts. Therefore, to develop more efficient conservation strategies it is essential to know which are the suitable fish hosts of U. foucauldianus. In this study, two approaches were used to assess the fish hosts of U. foucauldianus: the determination of infestation rates of fishes under natural conditions through monthly sampling (from January to June) in the Laabid River (Oum Rbia basin) and the N'Fis River (Tensift basin), and artificial infestation in laboratory trials using fish species from both rivers. The natural infestation of fish was detected from February to June, with a peak in May. Fully metamorphosed juveniles were only detected in native fish species, i.e. Luciobarbus ksibi (Boulenger, 1905), Carasobarbus fritschii (Günther, 1874), Luciobarbus zayanensis Doadrio, Casal‐lopez & Yahyaoui, 2016, Labeobarbus maroccanus (Günther, 1874), and Luciobarbus magniatlantis (Pellegrin, 1919). The two non‐native fish species used do not function as effective hosts. Given the increasing human pressure on native fish species in the Mediterranean biodiversity hotspot, including the increased number of non‐native fish introductions, urgent conservation measures are discussed for this and other freshwater mussel species.

Single or multiple spawning? Comparison of breeding strategies of freshwater Unionidae mussels under stochastic environmental conditions

The life cycle of unionids is characterized by a obligatory period of larval parasitism on a fish host, any disturbance of which might cause a large-scale decline in the mussel population. Because the probability of fish infestation is so important, we modelled what would happen to a population (in terms of population growth and probability of extinction), if the same number of glochidia were released in one or more separate spawning events, by a hypothetical mussel population living in conditions differing in the probability of fish infestation (a “neutral” scenario, a “good” one and three variants of a “bad” one). The single brood strategy was the best in the “good” scenario. However, when the frequency of unfavourable stochastic events increased (“bad” scenarios), all strategies led to population decline, the single brood strategy being the worst. In “good” and moderately “bad” conditions the double brood strategy performed better than the other multiple brood strategies, but as infestation conditions deteriorated, a greater number of spawning events ensured a slower population decline and longer persistence. Our model can facilitate a better understanding of this problem and set up a framework for further tests in other unionid species and their environmental conditions.

Glochidial infestation of fish by the endangered thick‐shelled river mussel Unio crassus

Abstract Freshwater mussels (Unionoida) are globally threatened. The key to the development of effective conservation strategies for this group is to unravel their complicated life cycle, including the obligatory larva, which parasitizes the external tissues of fish. Artificial infestation was conducted for three fish species – Barbus barbus, Chondrostoma nasus, and Squalius cephalus – in order to study the prevalence, site, and intensity of infestation, in relation to the fish species and their individual body size. Fish gut contents were also examined, in order to analyse the possibility of glochidia consumption. Glochidia of Unio crassus are considered parasites of fish gills; however, this study revealed that U. crassus glochidia were attached to the fins of all the host species tested. The number of glochidia attached to C. nasus fins was four times higher than the number of glochidia attached to gills. The prevalence of fin infestation was higher for C. nasus and S. cephalus than for B. barbus. Infestation intensity was highest for C. nasus and lowest for B. barbus, and was also dependent on fin type. The number of glochidia attached to fins demonstrated a nonlinear (log10) relationship with fish body length. Inspection of dissected fish guts showed that all of the fish species tested foraged on glochidia: S. cephalus and B. barbus more frequently than C. nasus. Using predatory fish host species with non‐predatory species in mixed assemblages for artificial rearing of mussels led to increased mortality of fish and decreased infestation intensity. The best conservation practices for freshwater mussels should therefore be based on single fish species that are easy to infest and that do not prey on glochidia.

Parasite infestation increases on coral reefs without cleaner fish

Mutualisms are pivotal in shaping ecological communities. Iconic images of cleaner fish entering the mouths of predatory fish clients to remove ectoparasites epitomize their mutual benefit. Experimental manipulations of cleaner wrasse reveal declines in fish size and growth, and population abundance and diversity of client fishes in the absence of cleaner wrasse. Fishes grow more slowly and are less abundant and diverse on reefs without cleaner wrasse, both for larger species that are regularly cleaned and have high ectoparasite loads (“attractive species”), and for those smaller species that are rarely cleaned and are rarely infested with parasites (“unattractive species”). We therefore considered whether these previously observed declines in individual and population parameters on reefs without cleaners were related to increased ectoparasite infestation using an attractive species (Hemigymnus melapterus, Labridae) and an unattractive species (Pomacentrus amboinensis, Pomacentridae). Traps with these fish as a form of bait were deployed to sample blood-sucking gnathiid ectoparasites (Gnathiidae: Isopoda) on reefs from which cleaners (Labroides dimidiatus, Labridae) have been removed for 13 yr. Cleaner fish could not enter traps to access the clients/hosts, but gnathiids could enter the traps to infest hosts; thus, this method sampled the indirect effect of cleaners on gnathiid infestation of fish. Infestation was higher on reefs without cleaners than on those with them. The effect was only detected during the daytime when cleaners are active and only on the attractive species (H. melapterus). Thus, cleaner presence indirectly reduced fish exposure to parasites in a species that is highly susceptible to parasites, but not in one that is rarely infested with parasites. This suggests that cleaner presence indirectly reduces exposure of a common fish species to harmful parasites, which may explain some observed benefits in fishes at this location.

Response of Caligus rogercresseyi (Boxshall & Bravo, 2000) to treatment with Hydrogen Peroxide: Recovery of parasites, fish infestation and egg viability under experimental conditions.

Hydrogen peroxide (HP) is used to remove C. rogercresseyi from fish but little is known about its effect on this species. This study determined EC50 and concentration immobilizing 100% of specimens, capacity of parasites exposed to HP to recover and infest fish, and effect on survival into the copepodid stage. EC50 and concentration immobilizing 100% of specimens were estimated by exposing parasites for 20 min to 11 concentrations and evaluating effect at 1 and 24 h post-exposure. Capacity to recover and infest fish, and survival into copepodid were evaluated by exposing parasites and eggs to HP for 20 min. Recovery and fish infestation were evaluated at 25 and 24 h post-exposure, respectively. Eggs were grown until control reached the copepodid stage and survival calculated. EC50 was 709.8 ppm.100% immobilization was obtained at 825 ppm. Male and female recover 0.5 and 1 h post-exposure, respectively. Percentage of parasites exposed and not exposed to HP that were recovered on fish was not significantly different. Survival to copepodid was lower in those exposed to HP. HP effect is greater on copepodids, but 100% of the mobile stages are immobilized under 825 ppm causing detachment from fish and potentially driven away, reducing infestation risk.

Blood Description, Parasite Investation and Survival Rate Of Carp (Cyprinus carpio) Which Is Exposed By Spore Protein Myxobolus koi On Rearing Pond as Immunostimulan Material

ABSTRACTThis research is an experimental research to determine the effect of spore protein Myxobolus koi on grass carp (Cyprinus carpio) in rearing pond. The sample used is grass carp (Cyprinus carpio) 90 fish (10-15 cm). Spore protein used in this research is Myxobolus koi spore protein, that has been found by predecessor researchers and has been tested in laboratory as immunostimulan. The exposure was done orally, mixed in the feed, with a dose of 2 μg / gram dose of protein, feeded 1 time before being reared for 30 days. Parameters measured were: (1) leucocytes description (differentiated leucocytes of carp, (2) Parasitic infestation in carp and (3) Survival Rate / SR of carp were reared on pond for 30 days. The collected data is analyzed descriptively.The results showed that there was alteration of leukocytes description (differential leukocytes) in carp (Cyprinus carpio) as an indicator of the immune response. A leukocyte differential examination showed that exposure to the Myxobolus koi spore protein, The highest total lymphocytes occurred in carp exposed to Myxobolus koi spores protein and reared from pond in Mojokerto, were 77.6%, Monocytes of 16.3%, Heterophyll 14.4%, Eosinophils 7.6% and Basofil 0.4%. The highest infestation of Myxobolus koi occurred in fish that was not exposed to spore protein was 53.33% after 30 days of reared at pond, while parasitic infestation in fish exposed to spore protein was only 16.66%. Survival rate of carp indicated that the highest occurred in carp that exposed with spore protein and reared from pond in Mojokerto, equal to 90%.Myxobolus koi spore protein exposure given orally can makes alteration of leukocytes description (differential leukocytes), Decreased parasite infestation and increased survival of carp fish reared for 30 days, with the result that Myxobolus koi spore protein can be developed as an immunostimulant material.Keyword: Myxobolus koi, Cyprinus carpio, spore protein, immunostimulant, infestation

Functional diversity of a parasite assemblages of the Chinese sleeper Perccottus glenii Dybowski, 1877 (Actinopterygii: Odontobutidae) and habitat structure of the host

Analysis of the functional diversity of the parasite assemblage of Chinese sleeper individuals, based on classification of parasites by the paths of fish infestation, was conducted. It was ascertained that individuals of the Chinese sleeper obtain mainly ecologically reduced variants of parasite assemblages in the acquired part of the habitat.

Паразитологический контроль объектов сельскохозяйственного рыбоводства

Objective of research: to perform the parasitological monitoring we have to study the
 parasite fauna in fishes from different fish farm factories, calculate the index of similarity, estimate
 the influence of abiotic and biotic factors on the ecosystem of fish-breeding reservoirs.
 Materials and methods: parasitological monitoring of factory fish farms was conducted by
 the method of complete and incomplete parasitological examination taking into account the data
 obtained from various fish-breeding reservoirs.
 Results and discussion: the parasite fauna of cyprinid fishes is represented by 56 species,
 carriage of causative agents of parasitic diseases in fishes is detected. Index of similarity of
 parasite fauna in carps has been studied and typification of agricultural reservoirs carried out.
 Index of similarity between the parasite fauna in carp and herbivorous fish was 22–33 %, carp
 and rough fish - 18–30,7 %.
 Influence of abiotic (oxidability, reduction of oxygen and nitrogen ammonia concentration,
 mineralization) and biotic – anthropogenic factors (violation of processing technologies, veterinary
 and sanitary rules of fish transport and fish farming operations) on fish infestation with parasites was studied.
 The role of parasitological monitoring in prevention and elimination of fish diseases was shown.

Trichodina Sp. as Bioindicator for Evaluation of Biochemical Oxygen Demand (Bod5) in Aquaculture Fish Farms (Ponds)

The present study include the using of the prevalence of the fish infestation by the protozoan Trichodina sp. as bioindicator for evolution of the biological oxygen demand BOD5 (lowering down of the dissolved oxygen DO) from Ainkawa fish hatchery. For this purpose, two handered and fourty (240) finger ling fishes of Cyprinus carpio were collected from six ponds (40 samples from each pond) and fishes were examined from December, 2012 to the end of february, 2013. Biological oxygen demands were measured by azid modification of Winkler method (through measuring of dissolved oxygen DO) for each pond. Results reveal that there are a direct relationship between the prevalence of fish infestation by the Trichdina sp. and the values of BOD5. The prevalence of fish infestation in each pond increased (57.5, 40, 27.5, 45, 15, and 42.5% respectively) with the increase of the values of BOD5 (9.2 , 8.0, 5.7, 8.1, 2.9 and 8.0 mg.l-1, respectively).

The prevalence of non-indigenous parasitic copepod (Neoergasilus japonicus) spreads with fishes of pet trade in Kerman, Iran.

Ergasilids are copepods living in the river mouth of freshwaters and parasitic on Teleost fish family in both natural and artificial environments. So far, 5 species of the copepod have been discovered that belong to the genus Neoergasilus. This copepod is most likely to be disseminated through aquarium trades, aquaculture and over-nutrition, or construction of sand carrying water. The females of Ergasilidae are external parasites attaching to the anal and dorsal fins and sometimes to gills and nasal cavities of fish living in freshwaters. In total, 552 pieces of ornamental fish (301 males and 251 females) with length of 5-10cm from fish (Poecilia sphenops) species (Singapore, Sandy, Dirigible and scorpion's tail) were collected from ornamental fish stores in different regions of Kerman, Iran during 1year in 2012-2013 and tested in order to examine Neoergasilus japonicus infestation. From 188 adult females Neoergasilus japonicus specimens recorded on the fish host, 8 (4.26%) were on the anal, 120 (63.83%) on the dorsal, 10 (5.32%), on the pectoral, 45 (23.94%) on the pelvic, and 5 (2.66%) on the caudal fins. In this study, the prevalence of parasitic copepod infestation from Dec. to May was 26.31, 27.69, 26.19, 14, 18.75, and 7.5%, respectively. There was no significant difference between infestation prevalence in indigenous and non-native fishes (P=0.18). There were significant differences between different months of year in the prevalence and intensity of Neoergasilus japonicas (P<0.05). There was significant difference between frequency distribution of Neoergasilus Japonicus infestation in different organs (P<0.05). The male fish infestation (16.3%) was significantly higher than female fish infestation (5.6%) (P<0.05). Considering that the Neoergasilus japonicus was first observed in native and nonnative ornamental fish in Kerman, further studies should be conducted on the copepod infestation in stores supplying ornamental fish in other parts of Iran to make more accurate judgments.

Histopathological alterations in the vital organs of Indian Major Carps with parasitic infestation in fish farms West Bengal, India

The study was conducted to investigate the histological changes of vital organs such as kidney, gills and brain with the mixed infestation of parasites in Indian Major Carps (IMC). The parasites such as Myxobolus spp., Thelohanellus spp., Trichodina spp., Dactylogyrus spp., Gyrodactylus spp. and Nematodes were observed in three IMC. Several histological alterations were observed in the kidney of Catla catla, Labeo rohita and Cirrhinus mrigala, which includes vacuolar degeneration in the epithelium of renal tubules, focal areas of necrosis, proliferation of bowman's capsule and many cases the renal tubules lost its shape and canalculi formation was observed. The gills showed focal areas of necrosis, exacerbated swelling of gill arch, deposition of distinct black melanin pigmentation at the basal point of the gill arch, loss of primary and secondary lamellae, prominent vacuolar degeneration and formation of vacuoles. The presence of protozoan parasites in brain tissue resulted necrosis of the brain tissue, black pigmentation, vacuolization of myelin sheath of nerve fibers and common degenerative changes. Aims: To study histological changes of vital organs such as kidney, gills and brain with the mixed infestation of parasites in Indian Major Carps (IMC). Settings and Design: The organs fixed in 4% formalin are transferred to 50% ethyl alcohol and stored for further analysis. Materials and Methods: Histopathological analysis was made as described by Roberts. Statistical Analysis Used: Nil. Results: Described in text. Conclusions: The present study brings about conclusion that impact of mixed infestation of the parasites on their hosts was severe. Histopathological changes were observed in vital organs which might be due to toxins released by different parasites or physical damage of tissue with the presence of parasites.

Brazilian catfish parasitized by Epistylis sp. (Ciliophora, Epistylididae), with description of parasite intensity score

The determination of mean intensity of parasitism for colony-forming sessile protozoan such as Epistylis has been a great problem in parasitological studies. Some alternatives have been proposed by researchers for laboratory and field conditions. This study describes the criteria to establish the parasitic intensity score for epistylidid infestation in fish. Parasite distribution and the host-parasite relationship in four species of Brazilian cultured catfish and their hybrids are discussed. The highest prevalence rates were found in the hybrid jundiara, Leiarius marmoratus male × Pseudoplatystoma reticulatum female (96.4%), followed by jurupoca, Hemisorubim platyrhynchos (60%), and the hybrid surubim, Pseudoplatystoma corruscans male × P. reticulatum female (52.7%). Positive correlation between parasitic intensity score and the fish size, weight, and relative condition factor were also observed. These findings indicate that Epistylis infestation in Brazilian catfish is an emerging disease in cultured fish.

Dynamics of metal uptake and depuration in a parasitized cyprinid fish (Rastrineobola argentea)

Infestation of fish by endoparasites may potentially influence metal uptake and elimination by the host. We quantified the metal uptake rate constant (ku) and efflux rate constants (ke) of radiolabeled Cd and Co in the cyprinid fish Rastrineobola argentea experimentally infected with the parasite Ligula intestinalis. During 24h, the accumulation of Cd and Co increased linearly with no evident steady state in uninfected fish, infected fish and in the parasite. Following aqueous exposures, the ku for Cd in parasites was about 3× higher than that of infected fish and 6× higher than for the uninfected fish. The ku for Co was up to 15× higher in the parasites than that of infected fish and 7.5× higher than for the uninfected fish. The ke for excretion of Cd were consistently higher for the uninfected fish than for the infected fish and also higher for uninfected fish than the parasite. The ke for Co for the uninfected fish was 1.4–2.0× lower than in the infected fish, but higher for parasites compared to uninfected fish (1.3–2.3×). Pulse-chase feeding experiments with radiolabeled copepods showed that Cd assimilation efficiency from food was higher in infected fish, while Co was assimilated more effectively by uninfected fish. The observed differences in metal dynamics between infected and uninfected R. argentea in the laboratory concord with differences in metal concentrations measured in natural populations in Lake Victoria. Our findings provide evidence that L. intestinalis infection enhances Cd accumulation, but depletes the essential Co in the cyprinid fish R. argentea. We conclude that the combined stress of parasites and pollution changes metal risks to fish hosts in a metal specific manner.

A review on the “in vitro” culture of freshwater mussels (Unionoida)

Many Unionoida are considered to be extinct, endangered, or of special concern. These bivalves have complex life cycle stages that limit successful culture. In nature, the larvae (glochidia) of these bivalves must successfully parasitize a host (mainly fish) in order to metamorphose into juveniles. The two artificial methods used to obtain juvenile freshwater mussels in laboratory are either by induced attachment to host fish or by in vitro culture of glochidia. This article is focused on the in vitro method that represents a novel and alternative process to fish infestation, offering the ability to obtain larger numbers of juveniles without the need for host fishes and reducing the overall costs of propagation. In vitro culture requires a medium which fulfills the nutritional needs of each glochidia species and avoids microbial contamination. Recently, this methodology has presented excellent results with survival and transformation rates up to 94% using host fish plasma. High efficiencies on growth, and survival rates (84%) of juvenile freshwater bivalve Hyriopsis myersiana (Lea, 1856) up to 120 days were obtained when reared in adequate recirculating aquacultural systems using a very specific diet. More research is still needed to demonstrate successful propagation, mainly concerning the media nutritional composition to increase glochidia transformation and juvenile quality.

Parasites modify sub-cellular partitioning of metals in the gut of fish

Infestation of fish by parasites may influence metal accumulation patterns in the host. However, the subcellular mechanisms of these processes have rarely been studied. Therefore, this study determined how a cyprinid fish ( Rastrineobola argentea) partitioned four metals (Cd, Cr, Zn and Cu) in the subcellular fractions of the gut in presence of an endoparasite ( Ligula intestinalis). The fish were sampled along four sites in Lake Victoria, Kenya differing in metal contamination. Accumulation of Cd, Cr and Zn was higher in the whole body and in the gut of parasitized fish compared to non-parasitized fish, while Cu was depleted in parasitized fish. Generally, for both non-parasitized and parasitized fish, Cd, Cr and Zn partitioned in the cytosolic fractions and Cu in the particulate fraction. Metal concentrations in organelles within the particulate fractions of the non-parasitized fish were statistically similar except for Cd in the lysosome, while in the parasitized fish, Cd, Cr and Zn were accumulated more by the lysosome and microsomes. In the cytosolic fractions, the non-parasitized fish accumulated Cd, Cr and Zn in the heat stable proteins (HSP), while in the parasitized fish the metals were accumulated in the heat denatured proteins (HDP). On the contrary, Cu accumulated in the HSP in parasitized fish. The present study revealed specific binding of metals to potentially sensitive sub-cellular fractions in fish in the presence of parasites, suggesting interference with metal detoxification, and potentially affecting the health status of fish hosts in Lake Victoria.

Food safety - related control measures in emerging aquaculture enterprises in Sub-Saharan Africa: compliance of Uganda's operations against international market requirements.

Selected commercial aquaculture enterprises in Uganda were evaluated for compliance with internationally recommended food safety-related control measures. Food hazard control measures at potential critical control points of: farm siting, farm facilities and premises, and facilities for feed processing and storage, chemical storage, drug storage and waste storage were evaluated. Requirements for traceability, legal and certification, standard sanitation operating procedures and food safety skills for farm workers were the other measures evaluated. On a scale of 0 - 5 where 0 denotes none, 1 very low, 2 low, 3 acceptable, 4 almost total and 5, full compliance, the majority of control points evaluated had average scores below 3, a minimum acceptable level of compliance with international guidelines. Feed processing and storage areas were the most deficient of the potential critical control points. Other significant deficiencies occurred in requirements for traceability of fish and use of on-farm standard sanitation operating procedures. Veterinary drug use, a common problem with aquaculture exports, was not an issue since none of the farms was highly intensive – a practice that would increase the risk of infestation of fish with pathogens and raise the need for use of drugs. The compliance gap requires food safety policy and practice interventions in Uganda and other sub-Saharan countries that plan to export products to highly regulated markets like in the European Union. Key words: Uganda, food safety, control measures, aquaculture compliance, Sub-Saharan Africa, international market requirements.