Muscovy and domestic ducks (such as the Pekin - which were developed from Mallards) are very different as they have been genetically isolated for over 50 million years. They can be crossed but you get some very interesting results. If you cross a Muscovy male with a Pekin female you will hatch moulards (or mule ducks); if you cross a Pekin male with a Muscovy female the progeny are called hinnies.
In Europe and in Asia many mule ducks are produced because of their large size, quality liver and reduced fat content in the carcass. Artificial insemination has been developed in ducks due to the desire to produce mule ducks. If left to mate naturally, the fertility is only 20-30%. Artificial insemination brings the fertility up to 80%. Whereas a Pekin takes 28 days to hatch and a Muscovy takes 35 days, a mule or hinny takes 32 days to hatch.
Approximately 60% of mule ducks are males. Some of their characteristics are like the Muscovy as they are large, quiet, slow moving and have long claws but are also like Pekin as they swim well, the males and females are much the same size and they do not fly.
Hinnies are not grown commercially. Males hinnies are much larger than female hinnies, like the muscovy, yet the females look like Pekins but fly quite well.
Mules and hinnies cannot reproduce. Both males are sterile and only the hinny females lay eggs (though they cannot hatch). If you have Muscovy and Pekin together, the chances are poor that they will cross but if they do, a hinny will probably be the result as Pekin males can catch Muscovy females easier than Muscovy males can catch Pekin females.
We do not produce mules or hinnies but thought you might enjoy
this material on this interesting aspect of duck production and
genetics.