Only proteins provoke an allergic reaction when ingested.

Try telling my dog that
He is allergic to beef and when I fed the food on vet advice I had queried the 'oils and fats' and was told to try it, the effect was, still allergic. If its from beef, he's allergic to it.

Allergic or intolerant there is a vast difference, an allergy is life threatening, an intolerance is not!

also, I'm wary of any food now, even if it says no beef, there have been times when I have fed everything on the ingredients list to him from food and he has been fine, fed the food and he has had 'a breakout' stop food and it stops. So even if it says no beef, it does not say it hasnt been in contact with beef....either that or what is on the ingredients lists are not true?

Under labelling laws anything less than 3% does not have to be mentioned (hence why I challenged Gnasher's posts re liver being high in carbohydrates; she said that liver contained 3% carbs and that is high;if 50% of something is HALF, and 25% of something is a quarter etc then 3% of something is miniscule!

Secondly, as in peanut allergies, a product does not have to CONTAIN nuts to be a problem; for example some people cannot eat bread because the oil used on the trays and runners is peanut oil!

So you are right to be concerned about ingredients that may not be immediately visible

What happens is he will get bad colitis to the point of losing kilos in no time and interdigital cysts, it started more mild but recently he had a TINY bit of beef (and I mean tiny) and had a major breakout then and coughing, breathing odd at times...the infection spreads, or has done from the cysts throughout his body. I think that must be a secondary infection though (from being 'at' his paws)

If this is what can happen with an intollerance (since he didnt die) I certainly would not risk feeding it to a dog with an allergy to eating a certain animal.

SB - his parents and siblings don't seem to have this problem and I know that his parents are eating beef tripe with their meals, do you have any idea what would cause this in only the one dog...?

nope!

allergies are a type of auto immune disease and you can have one member of a litter that has this, because it has been triggerred by something, the others may be predisposed or not.

IT is like you do not inherit diabetes itself, but you inherit the predisposition to develop it.

I have scrutinised the ingredients in this food n can see no mention of beef fat. I know from own experiences as a human, intolerances/allergies that diet n flora/good bacteria in the gut can make a big difference.

Thats what I thought before but every now and again I wonder about it and think - was it something in particular that triggered this....or would it just have developed regardless...?

(obviously I dont feed him beef) his health is fine, and in other ways he is so fit, has stamina, excellent muscle tone...good temprement, just this beef thing.