Dermatophytosis (ringworm) and its treatment approaches in Red Chittagong Cattle (RCC) calves under on-station condition

: Dermatophytosis (ringworm), an infection of the superficial keratinized structures of the skin and hair, is the most common contagious skin disease in cattle. It is a remarkable public and veterinary health problem reported from different parts of the world and causes great economic loss. A number of calves were simultaneously affected with this disease in the cattle farm of Bangladesh Livestock Research Institute (BLRI). So, this study was undertaken to develop a suitable treatment approach for controlling the disease in the herd. A total of 20 calves of Red Chittagong Cattle (RCC) were selected for the trial. All the experimental calves were divided into five groups namely – T 0 , T 1 , T 2 , T 3 and T 4 . T 0 group was kept as control and T 1 , T 2 , T 3 and T 4 groups were allowed for treatment. The drugs used for treatment were griseofulvin, streptomycin-penicillin, antihistaminic and vitamin AD 3 E in group T 1 ; ivermectin, streptomycin-penicillin, antihistaminic and vitamin AD 3 E in T 2 ; topical antifungal ointment, griseofulvin, streptomycin-penicillin, antihistaminic and vitamin AD 3 E in T 3 ; and topical antifungal ointment, ivermectin, streptomycin-penicillin, antihistaminic and vitamin AD 3 E in group T 4 . No drug was used in T 0 (control).The duration of the experiment was about one month. The fungal spores of Trichophyton spp . , and Microsporum spp. were observed in the samples (skin scrapping) under microscope using 20% potassium hydroxide solution. All experimental calves were observed after 7 days to know the response of the treatment. On the basis of visual observation the result was recorded on day 14. All experimental calves were observed after 7 days to know the response of the treatment. On the basis of visual observation the result was recorded on day 14. Calves in control group remain same. Calves suffering from chronic dermatomycosis or dermatophytosis (ringworm) can be treated with topical antifungal ointment, griseofulvin tablet, streptonmycin-penicillin injection, antihistaminic injection and vitamin AD 3 E injection as per dosages used in this experiment. If the case is acute, topical antifungal ointment and griseofulvin tablet may be recommended as treatment measures. Vitamin AD 3 E may or may not be used in this case.


Introduction
Dermatomycosis or dermatophytosis, commonly known as ringworm, is a fungal infection of kertinised tissue (skin, hair, and claws) which is caused by one of the three genera of fungi collectively called dermatophytes -Trichophyton, Microsporum and Epidermophyton.It is a remarkable public and veterinary health problem reported from different parts of the world and causes great economic loss (Calderone, 1989).The disease occurs more commonly in tropical than temperate climates particularly in countries having hot and humid climatic condition (Pascoe, 1976).Trichophyton spp.has been regarded as the main fungi causing ringworm in cattle (Quinn et al., 1994).A high incidence of clinical cases in the winter and of spontaneous recovery in the spring is common, but outbreaks also occur during the summer months, so that close confinement and possible nutrition seem to be more important in the spread of the disease than other environmental factors such as temperature and sunlight.Humidity is known to be important, a high humidity being conducive to multiplication of the fungus.Animal susceptibility is determined largely by immunological status, so that young animals are most susceptible (Radostits et al., 2000;Thomas, 2012).Most importantly, if the affected calves are not treated, their growth becomes very slow or retarded.Noticeably, some RCC calves were affected with ringworm in the cattle farm of BLRI in 2011.But these cases did not cure automatically and became complicated in course of time.Therefore, the present study was executed in order to find out the best and most effective treatment approach of ringworm in RCC calves.

Sampling
A total number of 20 skin scrap and broken hair samples were collected by sterile instruments from the margin of lesions of dairy cattle RCC calves suspected to dermatophytosis.Then, the samples were taken to the laboratory for further examinations.

Microscopic examination
Direct microscopic examination was performed.After treating with 20% potassium hydroxide solution, the samples were examined under light microscope.

Culture
Samples were cultured in growth medium and growth of fungus was observed after three days.

Animals and treatment
A total of 20 calves of Red Chittagong Cattle (RCC) were selected for the trial.One calf had acute dermatomycosis and the rest had chronic ones.All the experimental calves were divided into five groups namely -T 0 , T 1 , T 2 , T 3 and T 4 .T 0 group was kept as control and T 1 , T 2 , T 3 and T 4 groups were allowed for treatment by using Grisovin® tablet, SP-vet® injection, Astavet® injection and VITA-ADE® injection for T 1; Vermic® injection, SP-vet® injection, Astavet® injection and VITA-ADE® injection for T 2; Dermin® ointment (topical antifungal ointment), Grisovin® tablet (systemic antifungal tablet), SP vet® injection (antibiotic injection), Astavet® injection(antihistaminic injection) and VITA-ADE® injection (vitamin A, D 3 , E injection) for T 3; Dermin® ointment, Vermic® injection, SP vet® injection, Astavet® injection and VITA-ADE® injection for T 4. Dermin ® ointment (benzoic acid 6% and salicylic acid 3%) was applied topically twice daily.Grisovin ® tablet (griseofulvin) was administered@ 10 mg/kg body weight orally twice daily for 7 days.Vermic ® injection (ivermectin) @1 ml/50 kg body weight was injected subcutaneously twice with 7 days interval.SP-vet ® inj.(streptomycin-penicillin) @ 1 ml/10 kg body weight was injected intramuscularly once daily for 7 days.Astavet ® injection (pheniramine maleate) @ 1 ml/10 kg body weight was injected intramuscularly once daily for 7 days.VITA-ADE ® injection @ 1 ml/10 kg body weight was injected intramuscularly three times with 3 days interval.There were four calves in each group as replications.During trial the average age and body weight of the animals were 45 days and 25 kg respectively.The experiment was carried out during March-April/2011.The duration of the experiment was about one month.

Observation and data recording
All experimental calves were observed daily after 7 days to know the response of the treatment.On the basis of visual observation the result was recorded on day 14.

Results and Discussion
The fungal spores of Trichophyton spp.and Microsporum spp.were observed in the samples (skin scrapping) under microscope.Growth of fungus was observed in the growth medium (Figure 1).The study revealed that the drugs used in group T 3 cured the calves after 7 days of last drug administration, while the drugs used in other groups did not cure the calves after 7 days but cured after 14 days of last treatment.The best result, however, was found in group T 3 (Table 1, Figures 2 and 3).This treatment protocol was further applied to control group (T 0 ) and it was observed that calves in control group got cured within 14 days.Interestingly enough, the present findings were in agreement with Quinn et al., 1994 andRadostits et al., 2000

Conclusions
The present study suggests that RCC calves suffering from chronic dermatomycosis or dermatophytosis (ringworm) should be treated with topical antifungal ointment, griseofulvin tablet, streptonmycin-penicillin injection, antihistaminic injection and vitamin AD3E injection as per dosages used in this experiment.If the

Figure 1 .
Figure 1.Fungal growth in growth medium.