Capers are dried and then picked in a solution called brine which consists of water and lots of salt. Like with too much cheese or raw yeast dough, too much salt in a pup’s diet can cause sickness, diarrhea, lethargy, swelling and could even be life threatening. If buying capers in a jar, you should always check the ingredients to ensure it doesn’t contain anything that is toxic to dogs before allowing your pup to consume them. Your dog's stomach and digestive tract are sensitive, so introducing new foods could cause tummy upset. Always add new foods to your dog's diet gradually.