Garlic has been used for thousands of years for medicinal purposes to help boost the liver and cardiovascular system. It also has immune boosting properties and can aid in inhibiting bacteria and fungi growth. Garlic is also an appealing palatant to dogs, which is why we have included this in some of our products.
Many websites and vet clinics do list garlic as a toxin to dogs, as along with lots of other foods, it will be toxic in large enough doses. As a precautionary measure and to prevent misconceptions by pet owners, it is easier to advise not to feed garlic at all.
This also deters owners from thinking that if their animal will be fine with a little bit of garlic, they will be ok in large doses every now and then, or a little bit more won’t hurt as they are a big dog etc. With home cooking or feeding left overs, pet owners may not pay attention to how much garlic was included, or how much was in the portion that was fed to the animal. We ensure that the inclusion of garlic in our products is not only minimal, but consistent in each batch, as the same recipe and process is followed each time.
As you have seen, garlic regularly comes under attack regarding it’s harmful effect on dogs and cats. This is due to the fact that it shares an association with the onion, as they are both from the same genus, Allium: onions are Allium cepa, whereas garlic is Allium sativum. And even though they are related, garlic and onion don’t have the same composition so the effects they produce are very different.
Onions are known to produce ‘haemolytic anaemia’ in dogs and cats, which is where red blood cells are forced to burst. Dogs and cats are highly susceptible to onion toxicosis: Consumption of as little as 5g/kg bodyweight of onions in cats or 15 to 30 g/kg in dogs has resulted in clinically important hematologic (blood) changes. Onion toxicosis is consistently noted in animals that ingest more than 0.5% of their body weight in onions at one time. The compounds within onions which cause this effect are n-propyl disulphide and to lesser degrees, thiosulphate. These compounds though, are only found in miniscule amounts in garlic, so unless very large quantities of garlic are consumed, it is unlikely that the same side effects will be produced that consumption of onions can.
The following extract is taken from a scientific article on toxicities in dogs by Kovalicova et al (2009) (http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2984110/pdf/ITX-2-169.pdf):
Garlic (Allium sativum) is considered to be less toxic and safe for dogs than onion when used in moderation. Allicin and ajoene, pharmacologically active agents in garlic, are potent cardiac and smooth muscle relaxants, vasodilators, and hypotensive agents… Garlic extract was administered intragastrically (1.25 ml/kg of bodyweight (5g of whole garlic/kg) once a day for 7 days)… no dog developed hemolytic anemia.”
(Note that the dose administered in this study was roughly the equivalent of 10 cloves of garlic for a 10kg dog, and that some dogs did develop subclinical effects on their red blood cells at these high doses).
Therefore, to develop clinically significant haemolytic anaemia from garlic, the animal would need to have consumed a very large dose – well in excess of the doses contained within our products. It has been estimated (in The Complete Guide to Natural Health for Dogs and Cats by Dr. Pitcairn) that for a 5kg dog, a ‘safe’ dose of garlic would be half a clove per day. As a precautionary measure however, we do discourage owners from feeding home formulated diets inclusive of garlic without specific guidance from their veterinarian.