Occurrence of malformations in incubated chicks possesses serious health risks and also economic losses including reduction in egg production, death, and losses when doing veterinary care. One of the major effects of chick malformation to the farmer is a great reduction in the quality of the chick. The visual scoring system relating to chick defects including navel closure, legs, beak and residual yolk abnormalities have a high correlation to the early chick mortality and general chick performance. Chickens with deformed beaks have reduced feed intake, growth rate and impaired normal behaviors like preening, poor mental condition and social contact with their mate. Due to these production losses, the following objectives were formulated; determination of fertility and hatchability rates of incubated eggs, to determine and characterize the different chick malformations/deformities and the associated risk factors in Muhoroni Sub-County, Kisumu, Kenya. It was found out that the fertility rate was 96.97%, whereas hatchability rate was at 86.49%. Similarly, prevalence rate of chick malformations was at 1.22% with several risk factors associated with their occurrence. Mis-management of the incubator was reported to be significantly related with chick deformities. This is by poor manipulation of the incubator settings orientation, turning during incubation, faulty incubators and poor sanitation of incubators. Other factors include breeder strain, breeder age, and pre incubation egg storage. It was concluded that fertility and hatchability of incubated chicks in the study area was optimal though chick deformities such as crossed beak, one eye, bowlegs, scattered feather, one ear, unhealed navel, one nose, bent neck were reported that mainly occurred due to human error during incubation. It is therefore recommended that poultry farmers should get some basic training on egg incubation, egg storage, selection and handling, incubator hygiene and proper poultry feeding.
