I copied this from a TAMU article...it applies to Range cattle:
Nutritional Scours
Under range conditions, a calf adapts a pattern of nursing
that fills its needs. Nutritional scours can be caused by
anything that disrupts this normal habit. A storm, strong
wind or the mother going off hunting for new grass
disrupts the normal nursing pattern. When the calf does
get up to nurse, it is overly hungry and the cow has
more milk than normal, so the calf may overload,
resulting in a nutritional scours. This is usually a white
scours caused by undigested milk passing through the
intestinal tract. This type of scours usually presents little
problem in treatment. Many of these calves, if they are
still active and alert, do not require treatment. If the calf
becomes depressed or quits nursing, treatment should be
started. Oral antibiotics can be used for treatment along
with fluids, if the calf begins to dehydrate.
Now, if this is a bottle baby, it could still be nutritional scours...over feeding. I've read that nutritional scours are not particularly harmful to the calf...but I wouldn't bet the calf's life on it. I'd be giving that calf electrolytes as well as cutting back on the amount of milk liquid he's getting.
Bottle babies can really get overfed liquid. A full 4 pint bottle is just too much at one time. Mix your milk replacer with 3 pints of water instead of 4. Mix the electrolytes as directed, but only give a half bottle at a time. It's a lot of work, but it's better than one getting down with scours, whatever kind they might be.
We've also had calves that had white/gray scours that weren't from over feeding...and they got serious real quick. That's why I always give electrolytes about 2 hours after I feed milk replacer if I see a hint of scours.
And, that baby is old enough to start nibbling dry calf starter or calf manna and good grassy hay. Do you have any out? It makes a difference... ;-)
Range baby or bottle baby...myself, I'd still be giving electrolytes. Just my opinion. :)
Alice