Hematological changes in Eleginops maclovinus during an experimental Caligus rogercresseyi infestation

Abstract

Eleginops maclovinus has been an important fishery resource in Chile since 1957. Caligus rogercresseyi is one of the most prevalent ectoparasite species found on E. maclovinus. Hematocrit, hemoglobin level, red blood cell count (RBC), white blood cell count (WBC), mean corpuscular volume (MCV), mean corpuscular hemoglobin (MCH), mean corpuscular hemoglobin concentration (MCHC) and differential white blood cell count were determined before and after an experimental infestation with C. rogercresseyi. We found significant differences in the hemoglobin level, WBC, MCV, MCH, MCHC, hematocrit level and RBC between infested and uninfested fish. Furthermore correlations between number of C. rogercresseyi with hematocrit, MCHC, neutrophil, eosinophil and lymphocyte counts were found. Hematological reference ranges of E. maclovinus in captivity conditions were also established.

Hematological alterations in Astyanax altiparanae (Characidade) caused by Lernaea cyprinacea (Copepoda: Lernaeidae)

“…RBC parameters can be the fastest way to detect stress and blood loss caused by parasitic infestation in a fish population (Nair & Nair 1983, Fajer-Ávila et al 2011, Peña-Rehbein et al 2013, Ranzani-Paiva et al 2013). Thus, hematological evaluations have become a routine practice for assessing the health of a fish population.…”

“…In the present study, even at a moderate level of infestation, L. cyprinacea was able to induce a decrease in the condition factor of A. altiparanae, suggesting that in the case of this fish species, the effects of the parasitism may be more related to the size of the fish than the intensity of the infestation. In contrast, other studies have reported that the abundance of crustacean parasites per fish was not high enough to cause a reduction in the condition factor despite the gill injuries observed (Fajer-Ávila et al 2011).RBC parameters can be the fastest way to detect stress and blood loss caused by parasitic infestation in a fish population (Nair & Nair 1983, Fajer-Ávila et al 2011, Peña-Rehbein et al 2013, Ranzani-Paiva et al 2013). Thus, hematological evaluations have become a routine practice for assessing the health of a fish population.…”

“…Therefore, blood cell parameters may be good indicators of the health status of a fish population (Nair & Nair 1983, Ranzani-Paiva et al 2013. However, few studies have addressed the effects of the infestation of parasitic crustaceans on the hematological parameters of fish (Nair & Nair 1983, Silva-Souza et al 2000, TavaresDias et al 2007, Fajer-Ávila et al 2011, Peña-Rehbein et al 2013). This study investigated the effect of moderate levels of infection by L. cyprinacea on the hemato logical parameters of A. altiparanae from the Mogi-Guaçu River, part of the upper Pa raná River basin (Brazil).…”

“…In contrast, in the A. altiparanae from MogiGuaçu infested by L. cyprinacea, no alteration was observed in the total number of leukocytes. However, differing results for other fish species infested with different isopods (Nair & Nair 1983, Peña-Rehbein et al 2013) may be due to differences in infestation levels and in parasite strategies.In conclusion, the present study suggests that infestation with L. cyprinacea, even at moderate levels, reduces body condition and leads to normocytic− normochromic anemia, corroborating the importance of these parameters in the evaluation of responses against parasitic infestation with this parasitic copepod. In addition, the results of this study also suggest that, even at moderate levels, infestations with L. cyprinacea represents a potential risk to farmed A. altiparanae, as, even in such conditions, it can induce important physiological changes in this fish.…”

Untitled

“…(Shimura et al, 1983;Ranzani-Paiva et al, 1987;Ruane et al, 1999;Tavares-Dias et al, 1999;Haond et al, 2003), Ichthyophthirius multifiliis (Tavares-Dias et al, 2002), Argulus sp., I. multifilis and Dactylogyrus vastator (Küçükgül Güleç and Şahan, 2010), Henneguya branchialis (Sabri et al, 2009), Caligus rogercresseyi (Peña-Rehbein et al, 2013), Dolops carvalhoi , Dactylogyridae, Urocleidoides ermitus, Anacanthorus sp., (Correa et al, 2013), Clinostomum complanatum (Kaur et al, 2012), Trachelobdella lubrica (Çelik and Aydın, 2006), Monogenea, Protozoa, Crustacea (El-Seify et al, 2011), Anacanthorus penilabitus, Piscinoodinium pillulare, I. multifiliis, P. pillulare (Tavares-Dias et al, 2008) can influence blood parameters in different host fish. Only one study which investigates the impact of C. oestroides on the blood parameters of the fish is available.…”