Duck genotypes in India are generally grown in extensive conditions by small breeders. The purpose of breeding is to obtain meat and eggs to contribute a small amount to the family budget. These duck genotypes are known for their adaptability to the environment and their resistance to diseases. As per livestock census 2019, the duck population of India is 33.51 million constituting 4.0% of the total poultry population. Ducks are most abundant in Eastern (64.5%), North Eastern (16.02%), and Southern (12.60%) states of India. In most of the places, poultry farmers prefer rearing indigenous ducks under scavenging system. The flock sizes of ducks ranged from 2 to 9 ducks among different households in the surveyed locations. Plumage color and beak color are not defined in indigenous ducks. There is inter-individual variation in morphological and yield traits. The average first laying age in indigenous ducks ranges from 145 to 223 days and 17.0-38.5% owners do not supply any additional feed to their ducks. The mortality rate among chicks was observed to be higher at younger ages. The average annual egg productions per indigenous duck are very poor. However, most of the duck farmers earned a good amount of subsidiary income from duck rearing. Hence, selective breeding as a genetic tool could be utilized to improve the productivity of indigenous ducks.

Inbreeding, by virtue of its consequence on traits of interest, is a topic of major interest for geneticists and animal breeders. Based on meta-analysis conducted on 57 studies and seven livestock species considering a wide variety of selected traits, it was estimated that inbreeding depression corresponds to on average a decrease of 0.137 percent of the mean of a trait per 1 percent of inbreeding. The decrease was larger for production traits (reduction of 0.351%) than for other trait categories. For populations raised as purebreds, inbreeding depression may impact the economic income of breeders. There is a need for studies assessing the existence of an inbreeding purge phenomenon as well as the impact of inbreeding on adaptation capacities of livestock species. Promises brought by the development of dense genotyping as well as functional genomics will increase the capacities to improve our understanding and management of the phenomenon.