The system of breeding that is practiced when N'dama cows are mated by muturu bulls is

When N'dama cows are mated by Muturu bulls, the system of breeding that is practiced is crossbreeding. Crossbreeding is the process of mating individuals from two different breeds or populations. In this case, N'dama cows and Muturu bulls belong to different breeds. Crossbreeding is usually done to produce offspring with desirable traits that are not present in the parent breeds. The offspring of crossbreeding are usually more vigorous and healthy than their parents, a phenomenon known as hybrid vigor or heterosis.