In the past couple weeks, I've seen several articles on GMO animals. They are often created using cisgenic techniques or gene editing (i.e., moving genes within a species or "turning off" expression of existing genes), so they may (or may not) be more acceptable to consumers than transgenic GMOs. That said, the research suggests consumers are much more averse to genetic engineering in animals as compared to plants (for example, here's one recent study we conducted).
Here's a sampling of the stories and applications mentioned:
Tamar Haspel in National Geographic - mentions bird-flu resistant chicken (well, they're not actually resistant but they don't spread the disease).
David Cyranoski in Nature News - mentions "double muscled" pigs.
Hannah Devlin in the Guardian - mentions pigs resistant to African swine fever (includes a nice graphic).
Kat McGowan in Mother Jones - mentioned polled (or hornless) Holstein cows (bet you didn't know almost all dairy cows currently have to be dehorned), also mentions more heat tolerant cows.
This is an old one but don't forget the larger, faster growing transgenic salmon.
It will be interesting to see how this field develops and how consumers respond. Reducing proensity for disease and need for dehorning are clear animal welfare improvements, and of course more efficient animals mean less environmental impacts and lower prices. Will that assuage consumer concerns? Only time will tell.
Addendum: Ellen Goddard reminded me of this story on transgenic cows that have higher Omega 3s