Effects of sarcoptic mange and its control with oil of Cedrus deodara, Pongamia glabra, Jatropha curcas and benzyl benzoate, both with and without ascorbic acid on growing sheep: epidemiology; assessment of clinical, haematological, cell-mediated humoral immune responses and pathology.

Abstract

The aim of this study was to evaluate the therapeutic efficacy of commonly used acaricidal drugs in India and also to assess the effect of ascorbic acid (AA) as adjunct therapy in 72 growing sheep with sarcoptic mange, aged 5-6 months and weighing 20.4-31.7 kg. Eight replicates of nine animals were formed based on sex, and day 0 body weight. Another set of 12 healthy sheep (5-6 months old) constituted the healthy control group. Drugs were applied locally on the affected parts daily and recovery changes in skin lesions were observed at the time of every application. L-Ascorbic acid was administered intramuscularly. Skin scrapings were collected daily from each group and examined for the presence of mites. Blood samples from each group were collected and analysed for total erythrocytes, leucocytes, haematocrit, haemoglobin and lymphocytes on 0, 14th and 28th day post-treatment (PT). Cell-mediated (CMI) and humoral immune (HI) responses were assessed on 0 and 28 days PT. Within groups treated with the drug alone, recovery in oil of Jatropha curcas group was faster and lesions were free from mites after the eighth application. For each drug, the recovery was faster with AA as an adjunct therapy when compared with the group treated with the drug alone. Within all groups, recovery in oil of J. curcas plus ascorbic acid (OJC-AA) group was fastest and the lesions were mite-free after three applications. The overall mean values were higher for all haematological parameters in OJC-AA group. Recovery with respect to suppressed CMI and HI responses during infection was also faster in this group. Gross and microscopic pathological studies revealed a marked adverse effect of infection on skin, kidney, spleen and liver. The OJC-AA group indicated faster recovery. It is concluded from this study that oil of J. curcas was found more efficacious in controlling sarcoptic mange in sheep and AA might be beneficial as adjunct in case of sarcoptic mange to get quick recovery with lesser applications of main therapy. However, the pharmacology of AA with reference to health of skin needs to be investigated.