Acaricidal potency of polyherbal spray against <em>Rhipicephalus microplus</em> and <em>Hyalomma anatolicum</em> infestation in cattle

Introduction

Tick infestation produce heavy economic losses to livestock industry due to blood sucking and irritation due to bites. Direct effects like loss of blood and reduction in body weight gain are responsible for decreased productivity of livestock across the world. Some of the tick species are also responsible for transmission of hemoprotozoan and rickettsial diseases like theileriosis, babesiosis, anaplasmosis and ehrlichiosis in animals (Estrada-Pena et al. 2004; Holdsworth et al. 2006; Salih et al. 2015). So tick infestation presents a serious threat to animal farmers across the world (Sumbria et al. 2016). Control and eradication of tick infestation in livestock is a major managemental challenge to reduce the economic losses to dairy farmers from direct and indirect losses (Davey et al. 2010; Rao et al. 2014). Organophosphates, pyrethroids, formamidine and macrocyclic lactones are the major classes of acaricidal chemicals used for tick control since long time (Davey et al. 2010; Rao et al. 2014). Intensive and indiscriminate use of acaricides for control of ectoparasite has culminated in emergence of resistance among different strains of tick populations (Bianchi et al. 2003; Pegram et al. 2000).

To overcome the pressure of resistant strains as well as to reduce the side effects of chemical acaricides, there is need to investigate the efficacy of alternative and eco-friendly products against tick infestation. Few novel preparations of herbal base have been tried against tick infestation since last decade. Among the extracts of Azadirachta indica, Prunus persica, Mangifera indica and Psidium guajava, the extracts of A. indica revealed very high level of efficacy (80%) against Boophilus microplus ticks during in vitro studies (Srivastava et al. 2008). Out of eight medicinal plants screened for in vitro acaricidal properties, extracts of seeds of Annona squamosa revealed highest efficacy (70.8%) against IVRI isolates of B. microplus ticks (Magadum et al. 2009). So taking into consideration the limitations of chemical acaricidal drugs, the present study was undertaken with objectives to evaluate the acaricidal potential of polyherbal spray for the control of tick infestation in cattle and to assess the potential of spray as an alternative to chemical acaricides.

Materials and methods

Twenty cases of tick infestation in cattle irrespective of age, sex and breed of indigenous cattle were randomly selected for the study. The ticks of B. microplus (Rhipicephalus microplus) and Hyalomma anatolicum species were identified in selected cattle.

Single application of polyherbal spray (Clear Ticks Spray provided by Rakesh Pharmaceuticals, Kalol, Gandhinagar, Gujarat, India) containing Andropogon citrates (3%), Cymbopogon citratus (3%), Ocimum sanctum (2%), Pinus longifoia (10%) and 1% each of Calotropis procera, Datura stramonium, Aegle marmelos, Ricinus communis, A. indica, Allium sativum, Carica papaya, A. squamosa and Pongamia glabra was applied all over the body of study animals after measurement of tick count. Acaricidal potency of the spray was evaluated on the basis of reduction in tick count compared to pre-treatment counts. Tick counts were measured from seven heavily infested areas of body viz., ear pinna, inguinal region, under tail, back region, wither, dewlap and neck and expressed as mean tick count. Measurements of tick count were performed before application of spray as well as 3, 7 and 21 days after application of spray. Clinical signs like pruritus, scratching, rubbing, alopecia were recorded in tick infested cattle before treatment and 21 days post treatment. Blood samples were collected before treatment and 21 days post polyherbal spray treatment as per standard procedure and analysed for Hb, PCV, TEC, TLC, DLC and platelet count on fully automated haemoanalyzer (Diatron- Abacus Junior 3.11). Plasma samples collected before treatment and 21 days post treatment were analysed for glucose, total proteins, albumin and globulin on semi-automated biochemistry analyser (CA 2005) using diagnostic kits (Autospan Diagnostics Ltd. Surat, India).

Data analysis

Tick counts were analyzed for mean, standard error and analysis of variance (ANOVA) at P < 0.05 significance level while haematology and biochemical parameters were analysed for mean, standard error and level of significance (P < 0.05 and P < 0.01) with paired ‘t’ test by using SPSS software (Version: 16).

Results

A total of 20 cases of tick infestation in cattle were selected randomly for study. Various clinical observations in tick infested cattle were itching, alopecia, redness, rubbing and pruritus in areas with higher density of ticks. Skin coat was coarse with varying degree of hair fall. Treatment of cattle with polyherbal spray revealed significant reduction in clinical signs and hair fall from skin coat of affected cattle. Treated animals revealed improved lustre or shine on their hair coat on 21st days post treatment.

Acaricidal potency of polyherbal spray against tick infestation in cattle

Total tick count in cattle before treatment and over a period after treatment is given in Table 1. Total tick count in area of ear pinna, inguinal region, under tail, back region, wither, dewlap and neck was 180.9 ± 32.6, 105.7 ± 12.8, 47.0 ± 7.86, 61.10 ± 12.26, 119.45 ± 22.18 and 70.60 ± 11.86 respectively with mean total tick count of 94.97 ± 17.15 on day 0. Significant (P < 0.05) reduction in average mean total tick count from 94.97 ± 17.15 to 26.42 ± 5.97, i.e. by 72.18% was observed on 3rd day of treatment which was further reduced up to 4.62 ± 1.60 (95.13%) on 7th day of treatment. However, average total tick count was increased from 4.62 ± 1.60 to 25.34 ± 3.12 on day 21 after treatment.

Application of polyherbal spray revealed no adverse reactions like irritation, itching, salivation in study animals. Application of polyherbal spray revealed reduction in the degree of fly infestation on the body of cattle and so reported to have additional fly repellent activity.

Effect of polyherbal spray on haematological parameters

Complete blood count was performed on blood samples collected before start of treatment and 21 days post treatment in study cattle. Highly significant (P < 0.01) increase in total erythrocyte count and hematocrit was observed on 21 day post treatment in cattle treated with polyherbal spray compared to pre-treatment values (Table 2). Monocyte count also revealed significant (P < 0.05) increase 21 days post treatment compared to day 0 values. No significant difference was observed in pre and post-treatment values of total leukocyte count, haemoglobin, granulocyte, lymphocyte and platelet count in treated cattle.

Effect of polyherbal spray on biochemical parameters

No significant difference (P < 0.05) was observed in values of plasma total proteins, albumin, globulin and glucose in cattle infested with tick on day 0 and 21 days post treatment (Table 3).

Discussion

Ticks are blood sucking parasites of livestock which are also responsible for transmission of several dreadful haemoprotozoan diseases causing heavy financial losses to livestock industry. Female R. microplus tick ingests around 1 ml of blood from host during parasitic phase causing weight loss of around 1 g and loss of milk production by 8.9 ml in dairy cattle thereby reducing the milk yield and economic losses to the tune of 7.30 USD/head/year (Jonsson 2006; Jonsson et al. 1998). Taking into consideration the drawbacks of conventional chemical acaricides, herbal acaricides/phytopesticides are now emerging as a potential option for control of various ectoparasitic infestations (Habeeb 2010). Very few studies are published signifying the in vivo efficacy of herbal acaricides for control of tick infestation in cattle. Promising acaricidal activity of A. squamosa seed oil comparable to pyrethrins and moderate efficacy with A. indica seed oil was observed against B. microplus, H. anatolicum and R. haemaphysalis both in vitro and in vivo (Kalakumar et al. 2000). Rapid knockdown effect of mixture of aqueous extracts of five herbs (A. indica, M. indica, Polyalthina longifolia, A. squamosa, Ficus benghalensis) in 32 s was observed against R. microplus ticks in vitro compared to extracts of same plants alone indicating additive/synergistic effect in mixture (Parate et al. 2014). Efficacy of Keetguard Liquid, a polyherbal ectoparasiticidal against R. microplus tick infestation was evaluated in buffaloes at 1:20 dilution. Thrice application of preparation per week revealed 95% efficacy on 7th day post treatment which persisted up to 90% till 30 days post treatment (Tripathi et al. 2016).

In the present study polyherbal spray prepared from 13 different herbs might be having additive effect in significantly reducing tick burden as well as improving red blood cell parameters. Mean tick count was significantly reduced up to 95.14% on 7 days post treatment in study cattle while it showed increasing trend up to 73.31% on 21 days. Increase in tick count on day 21 might be due to short residual effect or entry of new ticks on body from breeding places in cattle sheds.

Use of polyherbal spray against R. microplus and H. anatolicum infestation in cattle proved effective in reducing the tick count and thereby significant improvement in haematological parameters demonstrating the acaricidal potential of these herbs as well as potential alternative ectoparasiticide for controlling tick infestations in cattle.