We all know that Universal has no plan for making a Balto 4, and that it's been a long time since they've forgotten everything about An American Tail.

And now, it's Land Before Time turn...

It's now "official" : Universal has stopped with the Land Before Time sequels, as well as the TV series.

This is a little bit of information I've found on a reliable site :

Universal Cartoon Studios has shuttered the long-running Land Before Time and continues with the popular Curious George, delighting the tots on PBS.

Source :
http://www.animationguild.org/

I contacted the author who posted this, and here's what he answered :

Land Before Time (series and features) is shut down.  Its longtime director Charles Grovesnor has moved on to other projects.
 
Nothing (that I know of) re "Balto."
 
Don't have any e-mail contacts, I get my information by walking through the place.
 
Nothing about Balto either, but I won't say I'm really surprised - at least it confirms that they truly have nothing planned for Balto currently (and neither Land Before Time)
I think we can officially say this is the end of the Universal sequels, as we know them.

Meanwhile, Universal is preparing its very first 3D animated film, named The Tale of Despereaux and meant to be released on late 2008...