Introduction

Dermatophytes are among the most frequent causes of dermatological problems in domestic animals. They are classified in three genera, Epidermophyton, Microsporum, and Trichophyton which include about 40 accepted species. However, only a few species belonging to the genera Microsporum and Trichophyton are usually the cause of dermatophytes in domestic animal [1]. They are usually divided into three ecological groups according to their main natural host or habitat: the anthropophilic (humans), the zoophilic (animals) and the geophilic (soil).

Animals serve as reservoirs of the zoophilic dermatophytes, and their infections have considerable zoonotic importance. Zoophilic dermatophytes such as M. canis, T. mentagrophytes var. mentagrophytes and T. verrucosum are significant causal agents of human ringworm in many areas of the world [1]. The incidence of dermatophytosis varies according to climate and natural reservoirs. However the pattern of the species of dermatophytes involved in dermatophytosis may be different in similar geographical conditions, both in human and animal [2]

In this study, the occurrence of dermatophytes and other skin mycoses found in toe webs of featherless broilers were investigated.

Materials and Methods

collection of sample

Sample Processing

Microscopy and culture of samples

Results

A total of 50 featherless broilers who presented with suspected superficial mycoses in the toe webs were examined during the investigation. Forty-one broilers (82%) were found to be mycologically positive by microscopy and culture. Only 5 chickens showed some scaling in their toe webs. The organisms recovered from those who presented with scaling were Microsporum gallinae, Microsporum gypseum, Trichophyton mentagrophytes var. mentagrophytes and candida albicans. Many fungi belonging to 7 different genera were recovered from the toe webs of 41 of the 50 featherless broilers samples studied. They included M. gypseum 9 (22%), M. gallinae 3(7%), T. mentagrophytes var. mentagrophytes 5 (12%), Fusarium sp 6 (15%), Scopulariopsis brevicaulis 2 (5%), Alternaria alternata 3 (7%), Aspergillus flavus 10 (24%) and Candida albicans 3 (7%). Non dermatophytes were recovered from 21 (51%) of the positive cases, dematophytes from 17 (42%) and yeast from 3 (7%). The frequency of distribution of individual isolates is shown in Table 1. Microsporum gypseum and Aspergillus flavus were the most commonly encountered dermatophytes and non dermatophytes respectively; while Candida albicans was the only yeast recovered.

Figure 1

Table 1. Frequency of fungi found from toe webs of 41 positive cases

Discussion

The study showed that toe webs of featherless broiler that may be considered healthy harbor varieties of dermatophytes non-dermatophytes and yeast. According to Lison et al., [7] pathogenic yeast can be isolated from healthy –looking toe webs. Featherless broilers according to Aaron [8] do not suffer from heat related mortality and can survive in low and hot environmental temperature.

In this study, some of the fungi isolated were also recovered by Oyeka [9] on human toe webs. This could be because keepers of most domestic animals (Poultry) entered their environment (habitat) with bare-foot (to avoid cross- infection), but infected human foot web may cross- infect the birds. Infection of human foot could occur as a result of wearing of shoes [8] as this may provide warmth and moisture on the toe webs required by fungi to grow and cause damages in the tissue.

The occurrence of dermatophytes has been previously reported in domestic animals [1]. The study recovered dermatophytes and other skin myxcoses from the toe webs of feartherless broilers. They included Microsporum gallinae ,Microsporum gypseum, Trichophyton mentagrophytes var. mentagrophytes, Alternaria alternata, Aspergillus flavus, Fusarium sp, Scopulariopsis bervicaulis and Candida albicans

Microsporum gypseum was the most commonly isolated dermatophytes. Others, Microsporum gallinae and Trichophyton mentagrophytes var. mentagrophyes are reqular pathogens of foot infection [9, 10]. These fungi have been found in soil/ dust in many parts of the world (11) and their presence in this study could be attributed to poor sanitation of the broilers environment.

The presence of Aspergillus flavus, Fusarium sp., Alternaria alternata and Scopulariopsis brevicaulis which are common soil saprophytes may be due to their ubiquitous nature of their spores in the environment and which can always be carried on healthy skin, toe webs inclusive. Fusarium sp has also been recovered from cases of foot infection, either alone or mixed with other pathogens [12]. This finding agrees with our study which shows that most fungi recovered were either alone or mixed with other Pathogens. Scopulariopsis brevicaulis has also been isolated in an indoor environment and can often cause inflammatory lesion on the skin [13, 14].

Candida albicans an opportunistic patogens known to produce a diverse range of Mucsosal and cutaneous as well as subcutaneous and systematic mycoses [15] was also isolated.

In conclusion, featherless broilers toe webs although bigger than that of feathered broiler harbor less fungi. This may be attributed to the particular temperature where they are kept with little contact with dust and soil. These birds can survive in low and hot environmental conditions in order to fully express their genetic potential of rapid growth and high meat yield unlike the feathered broilers. Finally the fungi recovered from the toe webs have been implicated in cases of mycotic skin disease and therefore cannot be regarded as ordinary normal flora of toe webs. These pathogens can cause infections under favourable conditions