[anonymous]

http://skeptvet.com/Blog/2018/08/grain-free-diets-and-heart-disease-in-dogs/ excerpt below, click on link for full article and comments:

Dr. Jennifer Larsen, a nutritionist at UC Davis, has written an excellent summary of the nuances of this issue, and she has agreed to let me share some of it here:
Taurine is not required to be present in dog foods. Taurine is an amino acid that is not nutritionally essential for dogs; however, there are dietary factors (such as protein source, fiber type and concentration, and cooking or processing methods) and individual dog characteristics (such as breed and calorie needs) that impact how efficiently taurine may be made and used by the body. The sulfur amino acid content and bioavailability in food is important though. The problem with dietary deficiency-related cardiac disease is multifactorial and is not just seen in goldens.
1- in many grain free diets, legumes are used to provide the carb (starch) but also protein and fiber – you cannot tell which ingredients are providing various proportions of nutrients from an ingredient list
2- legume protein is low in sulfur amino acids (methionine and cystine- the precursors for taurine synthesis)
3- some fiber types/concentrations increase fecal taurine content and promotes bacterial degradation of taurine (dogs and cats must use taurine to conjugate bile acids) so taurine recycling is not as efficient and more is lost
4- dogs need an adequate supply of precursors and to be able to make taurine fast enough to replace obligatory as well as excessive losses. When Newfoundlands and beagles were compared (during the Investigation into the lamb and rice issue with DCM in the 90s), it was found that Newfoundlands made taurine more slowly, so there are differences among breeds and probably individuals
5- dogs with lower than predicted calorie needs (“easy keepers”) also might not eat enough food and therefore enough protein to supply adequate precursors
6- some grain free diets (and other types of diets), are not high in protein (and therefore sulfur amino acids) since they use more expensive exotic or uncommon sources.
Any of these or a combination may impact taurine status in the dog.
There have been recent cases seen in our hospital and elsewhere of dilated cardiomyopathy secondary to taurine deficiency in dogs that have been associated with commercial diets containing certain ingredients (such as legumes – beans, lentils, and peas – and root vegetables – white and sweet potatoes). Data collection and interpretation is ongoing for these recent cases.
In the past we have also seen cases of dilated cardiomyopathy and taurine deficiency in dogs eating home-prepared diets (with either cooked and raw ingredients and those with and without meat), and other commercial diets with various ingredients and nutritional profiles. Some of those cases and investigations have been published (others can be found on PubMed):

• This reply was modified 7 years, 3 months ago by anonymous.