RESUMO
ABSTRACT Aspects related to epidemiology of flies belonging to Fannia genus were studied in order to determine predisposing factors for its occurrence in layer hens houses of commercial farms in the state of Minas Gerais, Brazil. An observational, analytical and sectional survey was conducted to verify major epidemiological aspects associated to infestations. This research was accomplished starting from an adapted secondary database of and structured with information on the presence and absence of ectoparasites and arthropods, characteristics of chicken houses, the poultry, type of facilities, geographical location and the management. The study was conducted in four hundred and thirty one houses located in forty three farms visited in 2012 year in the state of Minas Gerais. Ten farms (23.25%) and sixty eight houses (15,77%) were observed the presence diptera belonging to Fannia genus. The specie Fannia admirabilis was found in four farms (9,30%), Fannia albitarsis in two farms (4,65%) and only in one farm (2.32%) was observed the presence of Fannia canicularis. For three farms 6,98% was no possible to identify the species only Fannia genus. The epidemiological aspects for the occurrence of these flies were investigated using Poisson regression models. Characteristics such as farm, city of farm, presence of Histeridae beetles, type of facility (cage, on the floor with or without bedding) and the existence of mechanical removal of manure were associated with the occurrence of Fannia spp.
RESUMO
A genetically recessive albino mutation, which inhibits pigment development in the eyes, skin, and feathers of domestic chickens from Brazil, is described. This mutation appeared in a flock of completely black chickens of a private breeder. There are no information on the origin, breed, or specific line of the birds. Pigment inhibition is apparently complete in the feathers and eyes. Bird sight is very impaired, but no histological examination was carried out. Ratios obtained in F2 and backcrossed birds indicate that a single autosomal recessive gene is responsible for the condition. The data suggest that the absence of melanin in the eyes, skin, and feathers (symbol cc) is a mutation of the pigmented C wild gene.
RESUMO
A genetically recessive albino mutation, which inhibits pigment development in the eyes, skin, and feathers of domestic chickens from Brazil, is described. This mutation appeared in a flock of completely black chickens of a private breeder. There are no information on the origin, breed, or specific line of the birds. Pigment inhibition is apparently complete in the feathers and eyes. Bird sight is very impaired, but no histological examination was carried out. Ratios obtained in F2 and backcrossed birds indicate that a single autosomal recessive gene is responsible for the condition. The data suggest that the absence of melanin in the eyes, skin, and feathers (symbol cc) is a mutation of the pigmented C wild gene.