Levamisole reduces parasitic infection in juvenile pacu ( Piaractus mesopotamicus )

Abstract

Anthelmintic drugs are successfully used in aquaculture to control parasitic infections or infestations. This study analyzed the effectiveness of levamisole as an antiparasitic and its effect on the liver of juvenile pacu (Piaractus mesopotamicus). A total of 300 fish (180 ± 1.27 g; 16 ± 0.4 cm) were fed a diet containing levamisole hydrochloride (LHC) for fifteen days. A control group (T0) and four treatments were tested: T1 (100), T2 (150), T3 (300) and T4 (500) mg kg −1 LHC in quadruplicate (15 fish per repetition). Four fish per treatment (n = 20) were euthanized by sectioning the spinal cord; the sample was forwarded for parasitological analysis. The gill arches and intestines were removed and preserved in formaldehyde 10% for identification and quantification of the parasites. For evaluation of the liver histology, four fish per treatment (n = 20) were euthanized with benzocaine (100 mg L −1 ) for liver removal. In intestines and gills, we identified the parasites Rondonia rondoni (Nematoda, Atractinae) and Anacanthorus penilabiatus (Monogenoidea, Dactylogyridae), respectively. Both were at high prevalence and intensity of infection and infestation, respectively. The 300 mg kg −1 LHC treatment reduced the infection by R. rondoni but not the infestation by A. penilabiatus. Concentrations of 150 and 300 mg kg −1 LHC caused moderate liver changes, and no changes were observed in fish treated with 100 mg kg −1 LHC. The highest concentration of LHC (500 mg kg −1 ) induced a high occurrence of sinusoid dilation, blood congestion and leukocyte infiltration in fish liver. Our results indicate that LHC (300 mg kg −1 ) was effective in controlling the infection by R. rondoni and caused moderate histological changes in pacu liver.

Levamisole enhances the innate immune response and prevents increased cortisol levels in stressed pacu ( Piaractus mesopotamicus )

“…It has antiparasitic effect in production animals such as sheep [12], bovine [13], and also in the human species [14], paralyzing the muscles of the parasites in the host gastrointestinal tract [15]. Its antimicrobial effect on fish has been proven through the control of protozoa [16], nematodes [17,18], and bacteria [19]. In farmed fish, several studies demonstrate its immunostimulating effect, improving leukocyte production [20], respiratory burst activity [21], phagocytic activity [22,23], cytotoxic cell activity [24], oxidative radical production and serum myeloperoxidase [25], lysozyme [19,26,27], and complement system activity [19,21], although its mechanism of action is not known.…”

Pharmacokinetics of levamisole after intramuscular and oral administrations to Caspian salmon (Salmo trutta caspius)

“…Dietary levamisole at the dose of 300 mg/kg dry diet has been reported to enhance Clarias fuscus fish resistance to pathogenic bacteria and markedly influence specific immunity system, while administration of levamisole at the dose of 600 mg/kg dry diet for 7 days resulted in immunosuppression of fish (Li et al, 2006). Feeding levamisole 300 mg/kg supplemented diet for 15 days was effective in controlling nematodal infection in juvenile paco ( Piaractus mesopotamicus ); however, the same protocol with the dose of 500 mg/kg feed resulted in pathologic changes in fish livers (Pahor‐Filho, Júnior, Pilarski, & Urbinati, 2017). Studies also suggested that antiparasitic activity of levamisole against amoebic gill disease of fish might be due to its immunomodulatory activity (Findlay, Zilberg, & Munday, 2000).…”

High concentration of levamisole in the diet of Colossoma macropomum (Pisces: Serrasalmidae) is effective for controlling monogenean parasites

“…Levamisole is one of these anthelminthic drugs. This is an anthelmintic of imidazothiazole group that immobilizes parasites by causing muscle paralysis (HARTMANN, 1989;PAHOR-FILHO et al 2017). It has low toxicity towards fish in therapeutic baths (ALVES et al, 2019).…”

“…Levamisole can be delivered effectively via dietary supplementation, which would be much more feasible for industrial use, compared with injection and immersion baths (LI et al, 2006). Administration of levamisole in the dietary supplementation of fish may be an alternative for treatment against monogeneans, since this oral treatment can increase the deleterious effects on the parasites and increase the chances of fish survival (PAHOR-FILHO et al, 2017), especially when high concentrations of this anthelminthic drug are used. In addition, oral treatment eases the administration of the drug and there is no need to handle the fishes (TOJO & SANTAMARINA, 1998).…”