There are a number of plants in the common garden that can be toxic to dogs and many owners are unaware of the symptoms or the plants that cause problems.
Azaleas are very common but not many dog owners are aware that should their pet ingest the leaves or flowers it can cause vomiting and can cause depression, if eaten in large enough quantities it can be fatal.
Many flowering bulbs can be toxic to dogs. Daffodils and Narcissus can be seen in many gardens, the bulbs of both are toxic to dogs and will cause vomiting, diarrhea and may also cause dermatitis and can be fatal. Hyacinth bulbs can cause a skin allergy. Monstera Deliciosa bulbs can cause diarrhea and oral irritation and may also cause dermatitis.
Avocado can be harmful (both the fruit and pith) and can cause vomiting, diarrhea, labored breathing – can also be fatal.
Many seed kernels contain cyanide and can also be fatal to dogs for example Apricot kernels, Cherry kernels, Peach stones, even Apple seeds contain cyanide. Any of these if eaten in varying quantities can be fatal to a dog. Obviously the smaller the dog the less needs to be ingested for serious consequences to manifest.
The leaves of many common plants are also toxic, Mother-in Laws Tongue causes diarrhea and oral irritation and may also cause dermatitis. It can also cause tremors, seizures loss of balance and asphyxiation – needless to say this can be fatal. Philodendron leaves similarly can cause dermatitis, diarrhea and oral irritation. Oak tree leaves and acorns whilst not common in gardens can be common in parks, ingestion of either leaves or acorns will affect the dogs kidneys – symptoms take several days to appear and this can complicate identifying the cause. Chrysanthemum leaves whilst not often fatal can cause dermatitis. Dieffenbachia often kept as an indoor plant can cause diarrhea, oral irritation, dermatitis and can also cause tremors, seizures, loss of balance and asphyxiation – can be fatal.
These plants causing oral irritation have a very interesting mechanism: when dogs chew on the plant, a chain reaction results in the gelatinous plant material to swell, forcing raphides (needle like calcium oxalate crystals) to violently shoot out from cells. The calcium oxalate crystals then penetrate and embed themselves into the tissues of the mouth, tongue, throat and stomach causing (in most cases) immediate discomfort and aggravation as would be expected when millions of microscopic needles are lodged in ones throat and mouth!
Many vegetables can also be harmful to dogs. Onions and Garlic are highly toxic, the initial symptoms are vomiting and diarrhea and the animal will show little interest in food, they may also appear breathless. The dogs affected by onion toxicity are experiencing haemolytic anemia which is a condition where the red blood cells rupture whilst circulating. A small sized onion is sufficient to cause a fatality in a large dog. Tomato plants are also toxic and if large amounts of the plant are ingested it can cause vomiting and diarrhea, lethargy and weakness.
There are also a number of parasites that dog owners need to be aware of. Visible parasites include fleas, ticks and often ear mites, these are all easily treated with a topical treatment. An interesting fact is that fleas are the vectors or intermediate hosts for certain tapeworms – thus if your dog has a flea infestation, he also might have tapeworms!
Ringworm whilst not a parasite (it’s actually a fungal infection) is easily transferred to humans and other animals in the household, it is also easily treated with a topical treatment. Internal parasitical worms include roundworm, hookworm, tapeworm which again are easily treated. Hydatid tapeworm is easily treated unless infestation is severe. Toxoplasmosis can be contracted by the animal eating kangaroo meat that has not been cooked, despite oft repeated old wives tales it is not easily transferred to humans via infected dogs or cats or in cat faeces. Lungworm is carried by slugs and snails and is transferred by the dog eating an infected snail, it is easily treated if discovered in time.
I hope that the above has been informative.