Any idea on breed?

[juliejohnson805]

These were purchased at TSC and are supposedly a couple weeks old. Totally new to ducklings. This is what you get sending SIL to get feed.

 

[Pyxis]

Those are pekins

 

[KaylorFarms]

Those are pekins

I agree.

 

[DancingWthDucks]

Yep definetely Pekins....

 

[juliejohnson805]

When and how do you tell sex?

 

[Niche Flock]

If you are trained and knowledgeable, sexing is easy. If you have never done it before, be careful because you could potentially injure your ducklings. Oftentimes if it is your first time, it is easy to misread and assume "you don't see anything down there" and think you have females, only for ealize later that you sexed them incorrectly and you may or may not actually have males.
My first batch of ducklings from Hoover Hatchery was straight-run,not sexed so it was a gamble to see what nature would provide. Out of nine ducklings, I ended up with four drakes and five ducks. Not a good ratio to add to my previous flock of two females.
Easy way to tell gender if you are patient is to just wait. When they are a few weeks old and there duck noises become more apparent you can try the quack test. Pick up a duck if it quacks you have a female, if it has a hoarse whisper it is a male. Another way to tell is to wait and see if their tail feathers curl or not. Males tail feathers curl up and females don't. You will have to wait for their feathers to develop before you see this...
Also, I've noticed that the coloration amongst some of my runners gave away gender. The four that were males were a bit darker in color. That isn't always a good way to tell, but it ended up being true in this case.