Immune responses of Cyprinus carpio induced by protein extracts of Lernaea cyprinacea Linnaeus, 1758.

Lernaea cyprinacea Linnaeus, 1758 is an ectoparasite showing widespread infections in tropical aquaculture, and the present study aimed to determine the specific immune responses against this parasite. For the experiment, whole parasite extracts were injected intraperitoneally into Cyprinus carpio Linnaeus, 1758, and samples of epidermal mucus and blood were drawn at 0, 1, 7 and 14-days post-injection (DPI). The results revealed high levels of protein, protease and lysozyme activities in the experimental fish which were injected with L. cyprinacea protein extract. In the epidermal mucus, the total protein concentration of the control fish was 460 µg/mL, and the level raised significantly to 800 µg/mL in the experimental fish. The lysozyme activity increased from 741.5 u/mL to a peak level of 1448.5 u/mL at 7DPI. The protease activity was also found elated gradually from 2.91 u/µL to 4.49 u/µL at 1 to 14 DPI. In the serum samples, the protein concentration remained steady throughout the experiment period. However, all the experimental fish displayed statistically high levels of lysozyme and protease activity, from 890 u/mL to 1220 u/mL, and 6.10 u/µL to 11.88 u/µL, respectively. In the whole blood samples, the haemoglobin content and the red blood cells (RBC) count did not show any significant change in any of the experimental groups. But, the percentage of lymphocytes showed a marginal increase from 0.47 to 0.6 in the experimental groups. Overall, the immune responses induced by L. cyprinacea protein extracts depicts a pattern of specific responses, in which the local humoral responses dominate the systemic humoral/cellular response. The results further revealed the possibility of futuristic approaches to control freshwater ectoparasites.

Histopathology and external examination of heavily parasitized Lost River Sucker Deltistes luxatus (Cope 1879) and Shortnose Sucker Chasmistes brevirostris (Cope 1879) from Upper Klamath Lake, Oregon.

Shortnose Sucker (Chasimistes brevirostris) and Lost River Sucker (Deltistes luxatus) are endemic to the Upper Klamath Basin of Southern Oregon and Northern California, and their populations are in decline. We used histopathology and external examination of 140 and external examination only of 310 underyearling suckers collected in 2013, 2015 and 2016 to document pathological changes, particularly those relating to parasites. The most severe infection was caused by a Contracaecum sp., infecting the atrium of 8%-33% of Shortnose Suckers. The most prevalent infections were caused by Bolbophorus sp. metacercariae in the muscle of Shortnose Suckers (21%-63%) and Lernaea cyprinacea in the skin and muscle of Lost River Suckers (30%-81%). Histology detected Bolbophorus in only 5% of cases where it was not seen externally. Three myxozoans were observed; a Parvicapsula sp. in the renal tubules (10%), a Myxobolus sp. in the intestinal mucosa (2%) and an unusual multicellular, presporogonic myxozoan in the intestinal lumen of one sucker. Severe gill epithelial hyperplasia was observed in several fish collected in 2016. Trichodinids and Ichthyobodo sp. were observed on some of the gills, but absent in many of the fish with severe lesions. A histiocytic sarcoma was observed in sucker.

Identification of putative genes involved in parasitism in the anchor worm, Lernaea cyprinacea by de novo transcriptome analysis.

There is little information on the genome sequence of Lernaea cyprinacea a major ectoparasite of freshwater fish throughout the world. We subjected the L. cyprinacea transcriptome (adult and free living stages) to Illumina HiSeq 2000 sequencing. We obtained a total of 31,671,751 (31.67 millions) reads for the adult parasitic stage and 33,840,446 (33.84 millions) for the free living stage. The reads were assembled into 50,792 contigs for the adult stage and 69,378 for the free living stage. Using the pfam database, 41.91% of the transcriptome was annotated. The transcriptome was mined for genes associated with parasitism. To examine gene expression changes associated with the parasitism of L. cyprinacea during the transit from the free living to parasitic stage, we studied the differentially expressed transcripts between the two stages. The microsatellite markers were also identified (9,843 for adult stage; 16,813 for free living stages) and this would facilitate population genetic studies in various geographical isolates of Lernaea. Our data provides the most comprehensive sequence resource available for L. cyprinacea and demonstrates that Illumina sequencing allows de novo transcriptome assembly and gene expression analysis in a species lacking genome information. The data could open new avenues for a wide array of genetic, evolutionary, biological, ecological, epidemiological studies, and a solid foundation for the development of novel interventions against L. cyprinacea.

Molecular and morphological identification of Lernaea spp. in Cyprinid fishes from two districts in Yogyakarta, Indonesia.

Background and Aim: Parasitic infection commonly affects freshwater ornamental fishes. Parasites in fish may impede their growth and even cause death, resulting in a decline in fecundity. The prevalence of lernaeosis in aquaculture ponds in Indonesia requires attention because of missing data, especially from Yogyakarta. Therefore, this study aimed to identify the Lernaea species found in fish in Indonesia, particularly in Yogyakarta, molecularly and morphologically, as well as an overview of their distribution and the water condition they inhabit. Materials and Methods: Lernaea species were collected from three different fish species in two districts of Yogyakarta, Indonesia, for precise identification. Lernaea specimens were characterized morphologically and subjected to molecular identification based on 18S rRNA and 28S rRNA genes. Results: Lernaea in this study was morphologically and genetically confirmed as Lernaea cyprinacea, and the infection rate in each fish species was different. Water conditions might have contributed to the differences in infection levels. Conclusion: This study characterized L. cyprinacea isolated from Yogyakarta. Future research should focus on sequencing as much molecular information as possible and carrying out more experimental infections.

Natural infestation of an anchor worm, Lernaea sp. in cage culture of Asian Seabass, Lates calcarifer juveniles and its control using an anti-parasitic drug, emamectin benzoate.

Parasitic infestations and their control programmes are one among the challenges to be considered the most significant in aquaculture. A parasitic infestation was studied elaborately in Asian Seabass, Lates calcarifer juveniles with clinical signs, post-mortem findings, morphological and molecular identifications. In addition, those fish were also treated with emamectin benzoate (EMB) @ 50 µg kg-1 of fish body weight (BW) d-1 for 10 consecutive days under the controlled wet lab facility by feeding through the medicated feed at 4% BW. Results showed that the parasitic prevalence, parasitic intensity (PI) and mortality were 45.5%, 8.17 ± 0.15 per fish and 40% over a period of one week in that existing cage culture. The parasite was identified as a crustacean bloodsucker, anchor worm Lernaea sp. and EMB was found to be 100% effective with significant reduction in PI over a period of 10 days with improved survival rate of 90% against the untreated group. Infested but treated group revealed substantial haematological improvement in parameters such as RBC, WBC, Hb, PCV, large lymphocytes, small lymphocytes and total lymphocytes (P < 0.01). Similarly, comparative histopathology of vital organs also revealed no discernible lesions between the healthy and treated fish juvenile as compared to that of infested untreated group. Hence, EMB can be used to control the Lernaea sp. infestation in Asian Seabass.

Odds ratios and hurdle models: a long-term analysis of parasite infection patterns in endangered young-of-the-year suckers from Upper Klamath Lake, Oregon, USA.

We used odds ratios and a hurdle model to analyze parasite co-infections over 25 years on >20,000 young-of-the year of endangered Shortnose and Lost River Suckers. Host ecologies differed as did parasite infections. Shortnose Suckers were more likely to be caught inshore and 3-5 times more likely to have Bolbophorus spp. and Contracaecum sp. infections, and Lost River Suckers were more likely to be caught offshore and approximately three times more likely to have Lernaea cyprinacea infections. An observed peak shift seems likely to be due to a lower host size limit for Bolbophorus spp. (13.6 mm) compared with L. cyprinacea (23.4 mm). The large data set allowed us to generate strong hypotheses: (i) that a major marsh restoration project had unintended consequences that resulted in an increase in infections; (ii) that co-infection with Bolbophorus spp. increased the odds of infection by L. cyprinacea and Contracaecum sp.; (iii) that significant declines in the odds of infection over approximately 25 days were due to parasite-induced host mortality; (iv) that the fish's small size relative to L. cyprinacea and Contracaecum sp. might be directly lethal; (v) that the absence of L. cyprinacea infections in the early 1990s was associated with good year-class production of the suckers; and (vi) that parasites might increase the odds of vagrancy from the nursery ground.

Morphology is not a reliable taxonomic tool for the genus Lernaea: molecular data and experimental infection reveal that L. cyprinacea and L. cruciata are conspecific.

BACKGROUND: Species belonging to the genus Lernaea are cosmopolitan parasites that can infect many different freshwater fish hosts. Due to a high degree of morphological intraspecific variability and high levels of interspecific similarities, their classification is extremely difficult and controversial. Although the suitability of the shape of cephalic horns has been questioned decades ago by some experimental infection studies, this character still plays the central role in the identification of Lernaea spp. METHODS: We used the nominal species Lernaea cyprinacea and Lernaea cruciata to test the hypothesis that the shape of the anchor can exhibit host-induced morphological variability, and that the two taxa may be synonymous. RESULTS: We examined 517 wild or farmed specimens of five host fish species (four cyprinids and a mosquitofish), and found that all 16 parasite specimens collected from mosquitofish could be morphologically identified as L. cruciata, whereas the remaining 25 parasite specimens were all identified as L. cyprinacea. We experimentally infected goldfish and mosquitofish specimens with offspring (copepodids) of a single L. cyprinacea specimen: the adult parasites from goldfish were morphologically identified as L. cyprinacea, and those from mosquitofish as L. cruciata. We then used molecular data to corroborate that all these specimens are conspecific. CONCLUSIONS: Our results suggest that L. cyprinacea and L. cruciata may be synonyms, misidentified as different species as a result of host-induced morphological variation. Given the current shortage of molecular data for the genus Lernaea, in order to resolve the taxonomy of this genus (determine the exact number of species), future studies should aim to sequence as much molecular data as possible, and conduct further experimental infections.

Lernaeid parasites prevalence in commercial freshwater fish species at various fish farms in Pakistan

Abstract Reports abound on Lernaea parasitizing the brood stock, fingerlings, and marketable-sized culturable freshwater fish species in various parts of the world. We investigated seven small-scale aquaculture farms and how the prevailing Lernaea is impacting them. Randomly seven fish farms were selected to determine the prevalence percentage of lernaeid ectoparasites. Relevant information of the fishponds to estimate the various aspects such as effects of water source and quality, feed, stocking density, treatment used, and weight and length of fish, concerned with Lernaea infestation and prevalence was gathered. The results indicated that Catla catla (F. Hamilton, 1822) showed highest prevalence (41.7%) among the seven fish species, whereas Oreochromis niloticus showed zero. Other five fish species Ctenopharyngodon idella, Cirrhinus cirrhosis, Cyprinus carpio, Labeo rohita and Hypophthalmichthys molitrix showed 13.2%, 8.1%, 7.7%, 7.4%, 0.9% prevalence, respectively. In Royal Fish Farm 84.3% lernaeid infestation was observed, while no parasite was observed in the Vicents Chunnian fish farm. The water source, quality, feed, fertilizers, stocking density, water temperature, and potential treatment options displayed varying tendencies among fish farms and prevalence. Depending on the weight and length, the highest prevalence (56.7%, and 66.7%) was observed in 3501-4000 g and 81-90 cm groups. The infestation rate varied in various fish body parts with the dorsal fin the most vulnerable organ and showed 2.3% overall prevalence (while 18.4% contribution within total 12.6% infestation). Out of 147 infected fish samples, 45 were extensively contaminated by Lernaea spread. In conclusion, our findings confirm that Lernaea could pose a considerable threat to marketable fish, and various treatment options should be educated to the farmers to help mitigate the spread and potential losses. Furthermore, Catla catla is more vulnerable to Lernaea infestation (41.7%), so are the fish species being cultured at higher stocking densities.

Resumo Abundam os relatórios sobre Lernaea parasitando o estoque de cria, alevinos e espécies de peixes de água doce cultiváveis de tamanho comercial em várias partes do mundo. Investigamos sete fazendas de aquicultura de pequena escala e de que maneira a Lernaea predominante está impactando-as. Aleatoriamente, sete fazendas de peixes foram selecionadas para determinar a porcentagem de prevalência de ectoparasitas de Lernaea. Foram recolhidas informações relevantes sobre os viveiros de peixes para estimar os vários aspectos, tais como efeitos da fonte e qualidade da água, alimentação, densidade de povoamento, tratamento utilizado e peso e comprimento dos peixes, relacionados com a infestação e prevalência de Lernaea. Os resultados indicaram que Catla catla (F. Hamilton, 1822) apresentou maior prevalência (41,7%) entre as sete espécies de peixes, enquanto Oreochromis niloticus apresentou zero. Outras cinco espécies de peixes Ctenopharyngodon idella, Cirrhinus cirrhosis, Cyprinus carpio, Labeo rohita e Hypophthalmichthys molitrix apresentaram 13,2%, 8,1%, 7,7%, 7,4%, 0,9% de prevalência, respectivamente. Em Royal Fish Farm, 84,3% de infestação de Lernaea foi observada, enquanto não se observou nenhum parasita na fazenda de peixes Chunnian de Vicent. A fonte de água, qualidade, ração, fertilizantes, densidade de estocagem, temperatura da água e opções de tratamento potenciais exibiram tendências variadas entre as fazendas de peixes e prevalência. Dependendo do peso e comprimento, a maior prevalência (56,7% e 66,7%) foi observada nos grupos de 3501-4000 g e 81-90 cm. A taxa de infestação variou em várias partes do corpo dos peixes, sendo a nadadeira dorsal o órgão mais vulnerável e apresentou 2,3% de prevalência geral (enquanto 18,4% de contribuição dentro do total de 12,6% de infestação). Das 147 amostras de peixes infectados, 45 estavam amplamente contaminadas pela propagação de Lernaea. Em conclusão, nossos resultados confirmam que Lernaea pode representar uma ameaça considerável para peixes comercializáveis, e várias opções de tratamento devem ser educadas para os agricultores para ajudar a mitigar a propagação e as perdas potenciais. Além disso, Catla catla é mais vulnerável à infestação por Lernaea (41,7%), assim como as espécies de peixes sendo cultivadas em densidades de estocagem mais altas.

Chitosan-silver nanocomposites in goldfish aquaria: A new perspective in Lernaea cyprinacea control.

Nanomedicine is a promising new research area in human and veterinary science. Metal nanoparticles have shown high biocidal activity against bacteria, fungi and viruses, few studies have focused on antiparasitic action. Therefore, this study aims to investigate the influence of chitosan-silver nanocomposites on the fish crustacean parasite Lernaea cyprinacea. The disease was detected in goldfish (Carassius auratus) aquaria during the spring. Molecular and morphometric characterizations of the parasite were performed using polymerase chain reaction for rRNA and scanning electron microscopy. Chitosan-silver nanocomposites were characterized using transmission electron microscopy and Zetasizer. Probit analysis of parasite mortality versus the logarithmic concentrations of the composites indicated that the 1h/LC50 was 5.495ppm. Parasites exposed to the chitosan-silver nanocomposites showed severe pathological alterations and adsorbed the composite particles on their cuticles. After aqueous exposure of the infected fish to the compound at its LC50 for 24h, the female lernaeids were completely dislodged. Moreover, the pathological findings indicated rapid skin wound healing and renewal at the parasitic injury site. Therefore, we concluded that chitosan-silver nanocomposites are potential parasitic control agents for ornamental glass aquaria, as they have detrimental effects on aquatic predators, such as copepods.

Lernaea cyprinacea infection in a new host Puntius pulchellus in intensive culture system and its control by doramectin.

The present study explored the susceptibility of Puntius pulchellus subadults to Lernaea cyprinacea infection subsequent upon their first introduction to an intensive culture system that had a previous history of Lernaea infection and evaluated the efficacy of doramectin against the parasite. All the P. pulchellus introduced to the culture pond got infected demonstrating 100 % susceptibility of this species to Lernaea infection. Pathological changes caused by the parasite as evidenced by the extensive hemorrhage and tissue necrosis of the host at the point of parasite attachment was most severe in P. pulchellus. On the contrary, among the fish species already present in the pond and were previously exposed to the infection before the start of the present study, only Labeo fimbriatus developed mild to moderate infection. Cirrhinus mrigala, Ctenopharyngodon idella and Cyprinus carpio from the same culture pond did not develop Lernaea infection. Doramectin administration at 1 mg/kg b.wt. of fish incorporated in feed and given orally for 10 days or by a single intramuscular injection at 200 µg/kg b.wt. was found to be effective in controlling L. cyprinacea adult parasite infection in P. pulchellus. Doramectin hastened healing of the wounds caused by L. cyprinacea and did not cause any noticeable adverse reactions or toxicity to the fish host during the present study. In conclusion, P. pulchellus was observed to be highly susceptible to L. cyprinacea upon its first exposure to the infective stages of the parasite and a single intramuscular injection of doramectin at 200 µg/kg b.wt. was more effective than oral administration of the drug in controlling L. cyprinacea infection.

Complete mitochondrial genome of Lernaea cyprinacea (Copepoda: Cyclopoida).

The complete mitochondrial genome of Lernaea cyprinacea is 14,656 bp in size, containing 13 protein-coding genes (PCGs), 22 transfer RNA genes, two rRNA genes (12S and 16S), as well as two non-coding regions (NCRs, the control regions). The genome organization, nucleotide composition and codon usage do not differ significantly from other Copepodas. The complete mitogenome sequence information of L. cyprinacea provides useful data for further studies on phylogenetics, stock evaluation and conservation genetics.

Avaliação ectoparasitológica, hematológica e histopatológica de traíras Hoplias malabaricus Bloch, 1794 provenientes de açudes localizados no município de Sumé, estado da Paraíba / Ectoparasitologic, hematologic and histopathologic assessment of Hoplias malabaricus Bloch, 1794 from ponds located in Sumé municipality, state of Paraíba, Brazil

Hoplias malabaricus Bloch, 1794 é uma das espécies de peixes mais comumente encontrada nos açudes da Microrregião do Cariri Paraibano, todavia ainda não existem estudos na região sobre a sua fauna parasitária. Em virtude disso, o estudo objetivou caracterizar a fauna ectoparasitológica, o perfil hematológico e os achados histopatológicos das brânquias de H. malabaricus provenientes de quatro açudes localizados no município de Sumé/PB. Em cada açude foram capturados 10 exemplares e foi realizada a análise limnológica da água. Realizou-se a biometria dos exemplares e foram colhidas amostras sanguíneas por venopunção caudal. Os métodos de coleta de parasitos foram realizados segundo as recomendações da literatura. Além disso, foram coletadas amostras de brânquias para avaliação histopatológica. A comparação das médias foi feita pelo Teste Tukey a 5% de probabilidade. Os resultados mostram que a ectoparasitofauna de H. malabaricus provenientes de açudes localizados no município de Sumé/PB apresentou-se diversificada, sendo identificados vários táxons de ectoparasitos na superfície corporal e brânquias. A fauna parasitária promoveu alterações hematológicas e histopatológicas nas brânquias. Além disso, os resultados evidenciam uma relação de epibiose de Epistylis sp. com Lernaea cyprinacea e crustáceos branquiúros em H. malabaricus.(AU)

Hoplias malabaricus Bloch, 1794 is one of the fish species most commonly found in the micro-region ponds of Cariri in Paraíba; however there are no studies in the region on its parasitic fauna. Due to this, the study aimed to characterize the ectoparasitologic fauna, blood profile and histopathological findings of the gills of H. malabaricus from four ponds in Sumé/PB. At each pond 10 specimens were captured and limnological water analysis was performed as the biometrics of specimens and blood samples were collected by caudal venipuncture. Parasite collection methods were used according to literature recommendations. Also gill samples were collected for histopathological assessment. Comparison of the averages were made by Tukey test at a probability of 5%. The results show that H. malabaricus ectoparasite fauna from ponds located in Sumé/PB is diverse, once various ectoparasites taxons are identified on body surface and gills. The parasitic fauna promoted hematological and histopathological changes in the gills. The results show also an epibiosis relationship of Epistylis sp. with Lernaea cyprinacea and branchiurans crustaceans on H. malabaricus.(AU)

Seasonal variation of parasitism in pejerrey Odontesthes bonariensis (Atheriniformes, Atherinopsidae) from La Viña reservoir (Córdoba, Argentina) / Variação sazonal do parasitismo em Peixe-rei Odontesthes bonariensis (Atheriniformes, Atherinopsidae) no reservatório La Viña, Córdoba, Argentina

The pejerrey Odontesthes bonariensis is the most important freshwater fish of Argentina central region. The present study was conducted to describe the seasonal variation of parasitism in O. bonariensis from La Viña reservoir (31º 17'S, 65º 01'W), located in the province of Córdoba, Argentina. Between years 1999 and 2002, 573 fishes were caught, and their parasite infection and relative weight (Wr) were assesed. Three parasites were found, Lernaea cyprinacea (Crustacea), Contracaecum spp. larvae (Nematoda) and Cangatiella macdonaghi (Cestoda). Overall, Contracaecum spp. prevalence and intensity were very low. Lernaea cyprinacea and Cangatiella macdonaghi prevalences increased during summer and spring (P < 0.01), respectively. Lernaea cyprinacea infection showed also seasonal differences in intensity (P < 0.05), as well as C. macdonaghi regarding parasites density (P < 0.01). Cangatiella macdonaghi average parasites density was 32.0 (±22.5) cestodes per cm³ of digestive content. No association between parasitism and fish relative weight was found. Besides the seasonality variations observed, the parasite burden found did not compromise fish body condition.

O peixe rei Odontesthes bonariensis é um peixe de água doce de grande importância na região central da Argentina. O objetivo deste trabalho foi descrever a sazonalidade do parasitismo de O. bonariensis no reservatrio La Viña (31º 17'S, 65º 01'W), província de Córdoba, Argentina. Durante os anos 1999 e 2002 foram capturados 573 peixes. Nestes se fez à avaliação da condição corporal usando como parâmetro o peso relativo e identificaram-se os seguintes parasitos: Lernaea cyprinacea (Crustacea), Contracaecum spp. (Nematoda) e Cangatiella macdonaghi (Cestoda). As prevalências e intensidades de Contracaecum spp. foram muito baixas. Houve diferenças nas prevalências de L. cyprinacea e C. macdonaghi na época do ano (P < 0,01), sendo maiores no verão e na primavera, respectivamente. Houve diferenças estacionais na intensidade de L. cyprinacea (P < 0,05) e na densidade de C. macdonaghi (P < 0,01), neste ultimo alcançou-se um valor máximo nas amostras de 32,0 (±22,5) parasitos por cm³ de conteúdo digestivo. Não houve associação entre o parasitismo e o peso relativo dos peixes. Embora haja certa sazonalidade, as diferentes cargas parasitárias encontradas nâo prejudicam a saúde de O. bonariensis enquanto sua condição corporal.

Aspectos anátomo-patológicos da parasitose por Lernaea cyprinacea (L) (Crustacea: Copepoda) em tambaqui (Colossoma macropomum Cuvier, 1818) / Anatomo-pathological aspects of the parasitism caused by Lernaea cyprinacea (L) (Crustacea: Copepoda) in the "tambaqui" (Colossoma macropomum Cuvier, 1818)

Uma amostragem de trinta tambaquis (Colossoma macropomum Cuvier, 1818), com idade e peso variados, foi examinada para a detecção de parasitismo por Lernaea cyprínacea; sete deles apresentam o ectoparasita. Os peixes com lerneose possuíam idade entre quatro meses e um ano, com peso máximo de 1 kg. Vinte peixes adultos com idade acima de quatro anos, não mostraram a presença de L. cyprínacea. O número máximo de copépodes encontrados por hospedeiro foi três. As nadadeiras e suas bases de inserção no corpo foram o local mais comum de fixação nos peixes pesquisados. A lesão provocada por L. cyprínacea se apresentou, macroscopicamente, como uma hemorragia discreta e limitada ao ponto de inserção do copépode. A análise histopatológica demonstrou infiltração leococitária mononuclear e neovascularização com intensa hemorragia nos tecidos ao redor da estrutura de fixação do parasita. Em um exemplar, a reação inflamatória foi seguida de ulceração e pelo início de um processo de fibrose no local de penetração do parasita.

A sample of thirty specimens of the "tambaqui" (Colossoma macropomum Cuvier, 1818), was collected in the fish pond of the Agricultural College ldelfonso Bastos Borges at Bom Jesus de ltabapoana, State of Rio de Janeiro. They had varied ages and weights and were examined to detect the ectoparasite L. cyprinacea. Seven of them presented lerneosis and had from four months to one year with a maximum of 1 kg. Twenty adults specimens with more than four years did not present the parasitis. The maximum number of copepods per host was three and these parasites were usually fixed in the fins and in their attachment bases in the fish body. Macroscopically, the injury caused by L. cyprinacea showed a discrete and localized hermorrhage at the attachment area. The histopathological analysis exhibited a mononuclear leococitic infiltration and neovascularization with hemorrhage around the tissues of the appendages of the parasite. In some cases, the inflamatory reaction involved them, trying to isolate copepod from the tissue of the host. In one specimen, it was observed that the inflamatory reaction was followed by ulceration and by a fibrous process in the penetrating area of the parasite.