Both processed/manufactured pet food and raw ‘pet meat’ products can contain preservatives. There may be no legal requirement to label pet food products as containing preservatives.
There are safety issues relating to sulphur dioxide and sodium and potassium sulphite preservatives – these can cause thiamine (Vitamin B1) deficiency, which can be fatal.
Products specifically marketed for pets such as commercial fresh ‘pet meat’; ‘pet mince’ or processed/manufactured ‘pet food rolls’ may contain sulphite or potassium sulphite preservatives (sulphur dioxide 220, sodium sulphite 221, sodium bisulphite 222, sodium metabisulphite 223, potassium metabisulphite 224, potassium sulphite 225 and potassium bisulphite 228) that liberate sulphur dioxide.
Thiamine (Vitamin B1) deficiency can occur when dogs and cats are fed on a diet containing sulphite preservatives. Thiamine deficiency causes severe neurological symptoms and can be fatal. For decades, sulphite preservative induced thiamine deficiency has been frequently recognised by the Australian Veterinary profession. (Please note that thiamine deficiency can also occur when sulphur dioxide containing foods are fed in conjunction with foods not containing sulphur dioxide. This is because the sulphur dioxide in one food can destroy any thiamine present in the other food being fed at the same time).
The Australian Standard for Manufacturing and Marketing of Pet Food (AS5812-2017) contains clauses that address the sulphite issue by including a mandatory requirement that any product containing sulphur dioxide, sulphite or potassium sulphites must contain sufficient thiamine according to AAFCO guidelines, for the entire shelf-life of the product. This will help to prevent thiamine deficiency in relation to manufactured pet food.
The pet meat industry must ensure they take steps to safeguard pets from thiamine deficiency by including a mandatory requirement that any ‘pet meat’ product containing sulphur dioxide, sulphite or potassium sulphites must contain sufficient thiamine according to AAFCO guidelines, for the entire shelf-life of the product. This will be the requirement for any ‘manufactured pet food’ that complies with the Australian Standard and should be the requirement for any ‘raw pet meat’ products or any food intended for cats and dogs as well.
Sodium benzoate (E211) is another preservative used in a range of pet food products and products for human consumption. Cats appear to have a significantly lower tolerance for benzoic acid compared to rats and mice. At certain doses this preservative may be toxic to cats.
To minimise risks associated with preservatives the following precautions may be taken by pet owners:
- Choose high quality premium commercial foods (including wet food) that comply with the Australian Standard for Manufacturing and Marketing of Pet Food AS5812:2017.
- Ensure any raw meat/raw meaty bone products offered are human-grade only – You may wish to obtain these products from your local butcher, where appropriate legislation usually affords protection against the use of preservatives in human-grade meat products. However, avoid human-grade sausages, sausage meats and cooked manufactured meats as they can contain sulphites.
- Feed a varied diet.
- Talk to your vet for more information.
Articles of interest
- R. Malik & D Sibraa (2005) Thiamine deficiency due to sulphur dioxide preservative in ‘pet meat’– a case of deja vu, Australian Veterinary Journal, Volume 83 No 7.
- Bedford PG & Clarke EG (1972). “Experimental benzoic acid poisoning in the cat, Vet record (90):53-58.