Restorative effect of Azadirachta indicab aqueous leaf extract dip treatment on haematological parameter changes in Cyprinus carpio (L.) experimentally infected with Aphanomyces invadans fungus

Abstract

Common carp, Cyprinus carpio (40 ± 10 g) were inoculated through intramuscular route (2.5 · 10 5 cfu ml )1 ) with the fungal pathogen, Aphanomyces invadans. In the infected group, the total erythrocyte count (RBC), total leucocyte count (WBC), haematocrit (Hct), haemoglobin (Hb), lymphocyte (LYM), monocyte (MON), neutrophil (NEU) and eosinophil (EOS) deviated significantly (P < 0.05) from control values on days 24 and 36. Beginning on day 12 of infection, the fishes were dip treated for 24 days for 5 min daily in water incorporated with 1% aqueous leaf extract of Azadirachta indica (neem); the induced lesion gradually healed and the haematological values attained were near normal (P > 0.05) when compared with the control group.

Herbal supplementation diets on hematology and innate immunity in goldfish against Aeromonas hydrophila

“…The general concept that the use of herbals in aquaculture may produce various beneficial effects has been proven beyond doubt [16,17]. Recently the aqueous extract of A. indica and other herbals has been shown to restore hematological and biochemical parameters, and heal lesions in Cyprinus carpio and Labeo rohita suffering from either Aeromonas or Aphanomyces infections [16,17,36].…”

Current research on the use of plant-derived products in farmed fish

“…The administration of plant extracts to fish by immersion (Table ) has been tested in the treatment of diseases as alternative to traditional drugs and the protocols adopted included single or repeated treatments (Harikrishnan, Rani & Balasundaram ; Harikrishnan, Balasundaram & Bhuvaneswari ; Harikrishnan & Balasundaram ; Rajendiran, Natarjan & Subramanian ; Harikrishnan, Balasundaram, Moon, Kim, Kim & Heo ; Harikrishnan, Moon, Kim, Kim & Heo ; Rattanachaikunsopon & Phumkhachorn ). Dip treatment is logistically more practical for a large number of small fish (weighing less than 5 g) but dilution, exposure time and levels of efficacy are usually not well defined for the majority of immunostimulants (Sakai ; Galindo‐Villegas & Hosokawa ).…”

“…Interestingly, the use of traditional herbal medicines has been reported to restore the altered haematological parameters to nearly normal values and to heal lesions caused by Aeromonas hydrophila and Aphanomyces invadans in C. carpio and C. auratus (Harikrishnan et al . , ; Harikrishnan et al . ; Harikrishnan & Balasundaram ; Harikrishnan et al .…”

“…Immersion treatment with A. indica extract demonstrated a restorative effect in common carp experimentally infected with the fungus A. invadans (Harikrishnan et al . ) (Table ). Intraperitoneal administration of P. granatum extracts reduced the mortality of olive flounder infected with the lymphocystis disease virus (LDV) (Harikrishnan, Heo, Balasundaram et al .…”

Effect of Peanut (Arachis hypogea L.) extracts as a feed additive on growth and hematological parameters of rohu fish (Labeo rohita) fingerlings

“…Harikrishnan et al, (2005) observed that changes in differential count occur in response to an infection. Differential counts therefore were used as one of the tools for assaying the immune status of fish (Nussey et al 1995;Logambal, 1996, Misra et al, 2006.…”