Sorry, but I disagree with rice being a problem. Duck is a very rich meat. JWB would contain enough of it to cause digestive upsets. I have personally come across a number of animals who cannot eat duck or 'not common meats' likewise with animals who cannot tolerate the higher end high meat/no grain diets as they are far too rich for their tums. They can however tolerate the lower/mid range foods. Riley is doing well on the RC which does have rice as the first ingredient and I think 4th?
FF I appreciate you are a human nutritionist and as such have a strong interest, I do not have any scientific data just personal experience (having cared and fed hundreds and hundreds of pet/rescue animals).
I hope I have not offended you in any way and I apologise unreservedly if I have done so.
I think and write like a scientist which means my wording can sometimes come over as rude, in real life my clients appreciate my blunt explanations but of course they have the benefit of my friendly and smiley demeanor!
I am sorry but I don't understand what you mean by rich? I get that you mean a tummy upset but caused by what component of the duck? You cannot say that a digestive disturbance is caused by one component of a mixed meal unless you have matched the two foods for every other ingredient, and for quantities of each ingredient. I am passionate about this because of the fads for western humans to invent 'intolerances' to certain food groups (wheat, dairy) which, more often than not, are caused by them including refined foods in their daily diet or excessively large meals.
In humans we are talking about a digestive disturbance caused by foods or meals that are high in animal protein and/ or fat. As you say duck is certainly a fatty bird but there will be far less of the duck fat or duck protein in JWB as in the RC so the culprit is highly unlikely to be the quantity of animal protein or animal fat.
The enzymes needed to break down an animal protein (beef, duck, chicken) are basically the same, the difference is overloading the enzymes with a 'large dose'. I do not doubt your experience which is of course far greater than mine, but the chances are you are comparing foods with a different quantity of animal protein, animal fat, percentage of grains etc. so it's not possible to say that the specific meat or quantity of meat is the issue.
Cats are obligate carnivores, many of whom do not digest grains well. That doesn't mean I think no cat should ever eat grains again as it should be on an individual basis, and it doesn't mean I have counselled against using JWB or RC with Riley. I agree with you that slow introduction is often the key but my reasoning is that this would allow time for the gut flora to adapt, and for more of the enzymes needed to break down the extra carbs to their sugar base units to be produced. I also agree with you that this is a two way street, so cats accustomed to a high grain diet may struggle to digest a high meat food if there is no transition period.
I am getting my ingredients list from the RC PDF which lists rice as the third ingredient, I hope I am not using the wrong product?!
Looking at the nutritional breakdown the RC contains more protein, more fat and thus fewer carbs than the JWB. Compare the protein content is a little unfair as we don't know how much is from vegetable matter - JWB contains 9% potato protein and even more maize gluten suggesting the duck content is not high.
Interestingly the first ingredient of the RC is chicken liver, which many think to be a rich meat. From the same link "
Chicken, duck and rice are rarely involved in food allergy. These protein sources are highly digestible."http://www.royalcanin.co.uk/PDF/sensitivity_control_wet_feline.pdfhttp://www.wellbeloved.com/products/cat_food/duck__rice/adult.aspxHope that makes more sense!
