How do some of y’all keep your dog warm? I have a 55lb BLF who gets cold easy even on 40 degree days. Shet hunts in a neoprene vest all season out of a momarsh.

How does the vest fit?

Should be snug all around including around the neck and shoulders.

Dog should be fine in almost any weather with a tight, good fitting vest and a place to be out of the wind and water

Limit really long swims in frigid water, after long swims let them run around a bit on dry land before settling back in the blind.

BradyBuck has some good points.

I think she is probably fine. Heat is far more dangerous than 40 degrees. Over the last few years I know of 3 dogs that have died in the heat but none in the cold. In the last couple of years I have gone from retrieving dove in Texas to picking up ducks in North Dakota. (no vest)

She will certainly burn more calories (shivering is to create body heat) so handle this with plenty of good nutrition. What you can do is do your best to acclimate your dog to cool weather and cool water. Though this can be hard to do in Texas, have her spend more nights outside (or out of the HVAC) so that coat will thicken up. Take her swimming on those cooler days. The Momarsh is great - good choice. I use one all the time. This will help the water run off and help mitigate the cool temps. They also help give the dog great visibility.

Lastly, keep a few clean dry towels with you so after the hunt you can take off a bit of the moisture.

back when I used to duck hunt I would take a thermos full of cheap chicken noodle soup to the blind for the dog. When she got cold I would give her a little. If you have a good thermos you may have to let it cool a little.

I've never used one of these, but they look like a very good, tough and versitile product.
Would certainly help keep the dog warm/wind off of them.

http://thesugarcoat.com/

I have a 5mm that is a little looser on the dog specifically in the neck and i have a 3mm that fits like a glove all around. You think a tight fitting 3mm would be better than the 5mm?

Yes, if needed tailor the vest by pinching excess fabric, mark it, then cut and glue back with neoprene cement.

When I take the vest off my dogs they are completely dry anywhere the vest touches

Check out https://www.benik.com

They make custom vests for dogs. I got one for my jagd and it fights like a GLOVE.