Acaricidal efficacy of aqueous extract of Azadirachta indica leaves in cattle

Abstract

Efficacy of 70% (v/v) aqueous extract of A. indica leaves evaluated against cattle ticks. The group T1 and T2 were treated topically once in a day and twice at 24 hrs interval, respectively. The tick count in 10x10 cm areas on different regions of animal body was carried out before treatment and 24 hrs, 3rd, 7th, 14th and 28th day after treatment. On the basis of reduction in tick count with in the observed area on the treated animals per cent efficacy of extract was evaluated. The average tick count in T1 and T2 group was 55.80±11.29, 49.90±11.08, 35.40±7.95, 24.00±5.74, 17.90±7.35, 11.70±2.87 and 107.60±28.12, 97.00±27.85, 83.30±29.75, 70.30±30.51, 62.70±32.97, 18.80±5.05 on day 0 (pre-treatment), 1, 3, 7, 14 and 28, respectively. Progressive reduction in tick count with increase in per cent efficacy after treatment at various intervals were reported in both the groups. The statistical analysis revealed significant variation between different intervals in group T1 with significant reduction in tick count from 7th day (24.00±5.74), 14th day (17.90±7.35) and 28th day (11.70±2.87) post treatment as compared to pre-treatment tick count (55.80±11.29). In T2 group, the average tick count was found non-significant at various treatment intervals, however, it was markedly reduced on 28th day (18.80±5.05) after treatment as compared to pre-treatment tick count (107.60±28.12). Per cent efficacy was higher in T2 group (82.53%) than T1 group (79.03%) on 28th day after treatment. The reduction in tick count might be due to the most prominent phytoconstituent azadirachtin present in A. indica leaves. Clinical parameters in all the animals were within normal reference range at various treatment intervals and skin coat became smooth and shiny after treatment from 14th day with reduction in tick burden in both the groups.