Good grief!

How do you propose to make Bordelaise and Veloute sauces then?

(I don't eat bird meat either, but I wanted to be as specific as possible as your advice was referring to the sauces, not the birds)

EDIT TO ADD - OK, just found out that veloute can be made with fish or chicken, only times I've ever seen it on a menu was with cow. An old flat mate used to make Bordelaise sauce (he loved French regional food) but he was terrible about washing up after himself. I think of this stuff and I remember the smell of 3-4 day old bones in congealed fat. He was a good example of someone who enjoyed 70s food fads long after their popularity had waned - Beef Bourguignon, Chicken Chasseur... ugh, I feel ill remembering. I'm sure they're very appetising when freshly made by a good cook, but that rarely happened in 70s (or, in my experience, 90s) Britain.

---
Food fads from the 80s?
Beaujolais Nouveau