Pets are pretty much an owner’s child— you give them shelter, groom them and feed them, like you would to your own baby. They require a lot of effort and attention, since they can be vulnerable to external threats. Sometimes, these threats cannot be fought by a simple bark or exposure of canine teeth. For example, health risks in feeding are aplenty, including microorganisms and harmful elements. This includes mercury that are found in dog food.

Studies that tested some pet food have ultimately uncovered the fact that mercury concentration is high in fish-based canned food. Some of the data reveal that out of 14 out of 101 pet food samples contained mercury levels that are above what is considered to be safe for small mammals, which should only be 70 nanograms per gram or ng/g of mercury. Some samples contained mercury as high as 604 ng/g, which caused reasonable concern regarding these canned goods.

While it might be blurry to some why mercury in dog food is a health concern, you might want to check out these facts about mercury content in fish-based pet canned goods, and why you should avoid feeding them to your cocker spaniel.


In truth, mercury level in one canned fish pet food might not have much of an effect as soon as your pet ingests it. However, it gets harder to ignore once you regularly feed your dog the same pet food. Why? Mercury builds up over time, because the body cannot expel it readily. Even if mercury is consumed in little doses for every meal, it can stay in the body for long periods of time, adding up quickly.

Mercury is naturally occurring, but have it pool inside the body and it becomes a very potent neurotoxin. This means that it may cause adverse effects on the nervous system, which then affects all the other organ systems in your dog’s body.


Mercury poisoning is a gradual process, so it might be awhile before any changes are noticed, until after levels are high enough to cause severe reactions. There are several adverse effects, signs and symptoms indicating that your dog may be suffering from mercury overdose:

  • Abdominal pain
  • Blindness
  • Kidney damage
  • Anxiety
  • Abnormal behavior (i.e. chewing excessively)
  • Convulsions and tremors
  • Loss of coordination
  • Coma
  • Vomiting blood
  • Nervousness
  • Diarrhea (may be bloody)
  • Death



Hospitalization is the best option in mercury overdose. The pet will be given antibiotics, IV fluids, oxygen therapy and anti-inflammatory medicines to prevent the signs and symptoms from worsening. To expel the harsh element from the body, the vet may also use chelation medication and activated charcoal lavage.

If mercury poisoning is addressed promptly, there is a chance that the symptoms won’t progress to anything far worse. However, severe damage such as in the nervous system or kidneys is permanent and irreversible, and may decrease the dog’s quality of life.

Mercury poisoning is a serious health issue that can affect a dog’s well-being, so be sure to check your cocker’s food intake. Also, monitor the dog food label, and do some researching if possible. There are package labels that omit certain ingredients which may be harmful for your dog. The key to your cocker’s good health is to check that they are always eating right.