azadirachtin and Ectoparasitic-Infestations

In present study, a microcosm experiment is carried out to investigate the efficacy of 120 and 250-ppm crude aqueous extract of Azadirachta leaf on oocyte maturation, oviposition, embryonic development and hatching of the eggs of a fish ectoparasite Argulus bengalensis. Relative abundance of different maturing oocyte stages in the ovary of the parasite from different age groups was enumerated, and marked variations were obtained. Significant depletion in the abundance of pre-vitollogenic, vitellogenic and post-vitellogenic oocytes was recorded, which indicates impairment in maturation. Chromatin condensation of the oocytes of treated parasite indicates apoptosis of oogenic cells. Strong oviposition deterrence was evident by the elevated oviposition deterrence index of 0.18 and 0.52 at respective toxin levels. The treated parasites invested less number of eggs per oviposition, and hatching percentage of the eggs reduced markedly. In vitro treatment of eggs within 70 min of incubation exhibited coagulation of yolk material and subsequent reduction in hatching percentage. However, treatment applied after this critical period, hatching was not significantly altered. In vitro treatment of eggs at 80 min of incubation resulted in normal development. It signifies that azadirachtin affects the early developmental events but not the later. Presumably, azadirachtin either affects early gene expression of the embryo or antagonizes any of the substances of the zygote required for sustaining early developmental process. The result of the present experiment suggests that azadirachtin could be a promising agent to control argulosis through inhibition of the reproductive maturity of the parasite as well as through interference of its embryonic development.

Topics: Animals; Arguloida; Azadirachta; Ectoparasitic Infestations; Female; Fish Diseases; Fishes; Insecticides; Limonins; Oocytes; Oviposition; Plant Extracts; Plant Leaves

Argulosis hampers aquaculture production and alters the host physiology and growth. Azadirachtin is recognized as a potential antiparasitic agent against Argulus sp. The present study aimed to investigate the effect of different concentration of azadirachtin solution on haematological and serum biochemical parameters of Argulus-infested goldfish Carassius auratus. Ninety Argulus-infested goldfish were randomly divided into six equal groups. Fish of group 1-5 were treated with azadirachtin solution through bath of 1, 5, 10, 15 and 20 mg L(-1) as T1, T2, T3, T4 and T5, respectively, and group 6 was exposed to 2% DMSO solution without azadirachtin and considered as negative control T0(-). Along with six treatment groups, a positive control T0(+) of healthy goldfish free from Argulus infestation was also maintained. Parasitic mortality was evaluated after 3 days of consecutive bath treatment. After 7 days of post-treatment, the blood and serum were drawn from each of the treatment groups and haematological and serum biochemical parameters were evaluated. Total leucocyte count (TLC), mean corpuscular volume (MCV), mean corpuscular haemoglobin (MCH), blood glucose, total protein (TP), globulin, serum glutamate oxaloacetate transaminase (SGOT) and serum glutamate pyruvate transaminase (SGPT) were significantly (p < 0.05) high in negative control group when compared with positive control group. It could be concluded that Argulus infestation altered marked haematological and serum biochemical parameters. However, in treated groups complete elimination of Argulus was found in T4 and T5 groups. Also significant (p < 0.05) reduction in haematological and serum biochemical parameters of all the treatment groups were recorded in comparison with negative control group. In addition, T4 and T5 groups showed significantly (p < 0.05) high superoxide dismutase (SOD), catalase, total erythrocyte count (TEC) and haemoglobin (Hb). However, higher mean corpuscular haemoglobin concentration (MCHC), blood glucose and lactate dehydrogenase (LDH) levels in T5 group revealed that higher concentration of azadirachtin have notable effects on activity of vital tissues function and physiology of the host. Argulus spp. from infested goldfish could be eliminated using bath treatment with solution of azadirachtin having concentration of 15 mg L(-1) and that also shifted haematological and serum biochemical parameters towards homeostasis.

Topics: Animals; Arguloida; Biomarkers; Ectoparasitic Infestations; Fish Diseases; Goldfish; Insecticides; Limonins; Oxidative Stress; Random Allocation

Argulus is one of the most common and predominant ectoparasites which cause serious parasitic disease and is a potent carrier of viruses and bacteria in the ornamental fish industry. In recent years, organic (herbs)-based medicines are widely used to cure the disease, and neem (Sarbaroganibarini) medicine is very popular and effective throughout the world. The present study was conducted to find the effects of Azadirachtin against Argulus spp. on Carassius auratus under in vitro and in vivo conditions. The 96-h median lethal concentration (LC(50)) for Azadirachtin EC 25% against Carassius auratus was found to be 82.115 mg L(-1). The antiparasitic activity test under in vitro and in vivo was evaluated at 1 (T1), 5 (T2), 10 (T3), 15 (T4) and 20 mg L(-1) (T5) to treat Argulus for 3 h and 72 h, respectively. In vitro effect of Azadirachtin solution led to 100% mortality of Argulus at 20 and 15 mg L(-1) for 2.5 and 3 h, respectively. Whereas, under in vivo test, the 100% antiparasitic efficacy of Azadirachtin solution was found at 15 and 20 mg L(-1) for 72 and 48 h, respectively. The EC(50) for 48 h was 20 mg L(-1), and thus, therapeutic index is 4.10. The results provided evidence that Azadirachtin can be used as a potential agent for controlling Argulus.

Topics: Animals; Antiparasitic Agents; Arguloida; Ectoparasitic Infestations; Fish Diseases; Goldfish; Limonins; Survival Analysis

Azadirachtin-containing neem seed extract is a powerful insect growth regulator, a feeding deterrent and repellent with low toxicity. Unfortunately, azadirachtin degrades rapidly in light, excessive heat or alkalinity. Evaluations of azadirachtin on ectoparasites on animals have been scarce. The purpose of this work was to describe the effects of normal and potentiated azadirachtin on Ctenocephalides felis in the dog or cat. Groups of kennelled greyhounds and domestic cats infested with C. felis were sprayed once with azadirachtin containing neem seed extract with or without diethyltoluamide (Deet) and/or citronella. Methanolic extracts with 200, 1000 or 2400 ppm azadirachtin reduced fleas in a dose-dependent manner. Compared with fleas counted on treated dogs just before treatment and untreated infested dogs, 1000-2400 ppm azadirachtin reduced fleas 93-53% for 19 days. However, combined with 500 ppm Deet and 33% w/v citronella, only 500 ppm azadirachtin reduced fleas 95-62% for 20 days. On cats inoculated with 50 fleas 2 days before treatment, the combination reduced fleas and eggs 100% to day 6 and 83-51% from day 7 to 9. On petri dishes, the combination achieved 100% egg mortality up to day 7 and 80% to day 14 and 48-52% to days 21-28. Deet, with or without neem seed extract or citronella, and citronella, with or without neem, did not reduce fleas significantly. The results show that azadirachtin reduced fleas in a dose-dependent manner in flea-contaminated environments. In cats, the combination killed most fleas within 24 h, providing effective flea control for 7 days. The results suggest that Deet with citronella potentiated the effect of azadirachtin on C. felis.

Topics: Animals; Cat Diseases; Cats; Chromatography, High Pressure Liquid; DEET; Dog Diseases; Dogs; Dose-Response Relationship, Drug; Drug Synergism; Drug Therapy, Combination; Ectoparasitic Infestations; Female; Insect Repellents; Insecticides; Limonins; Male; Parasite Egg Count; Plant Oils; Siphonaptera; Triterpenes