Thursday, July 17, 2014

Heat stroke in Pets


Now that the warm weather is finally up on us after a long hard winter, we here at the Bowmanville Veterinary Clinic are seeing many people enjoying the outdoors with their dogs.  Outdoor cats, and even some rabbits and pocket pets are also enjoying the sunshine and spending increased time outside.  However with this warmer weather there are hazards that we as pet owners and veterinarians need to be aware of. 

 One of the dangers that comes with this hot weather is heat stroke.  Heat stroke is the elevation in body temperature due to environmental conditions.  A dog’s normal body temperature ranges from 37.5-39.0 C.  Temperatures greater than 41 C eventually lead to organ failure and ultimately death. The most common cause of heat stroke is being left in a car in warm weather, but it can also result from being left outside in the heat with no access to shade and water, or when exercised in hot and humid conditions. It can take less than 5 minutes in a car in the heat of summer to result in heat stroke.  Even on a cooler day the inside of the car can heat up considerably compared to outside temperatures and no animal should be left in the car.

If you have birds, rabbits, guinea pigs, chinchillas or other small mammals and you place them outside in their enclosure please ensure they have access to shade and water at all time.  It does not take long for these animals to get overheated.

There are some factors that can predispose an animal to heat stroke.  Some of these include age and respiratory conditions.  Brachycephalic breeds (short nosed dogs) such as Bulldogs, Pugs, Boston terriers are more susceptible to heat stroke due to their anatomy . 

Heat stroke also called hyperthermia requires immediate treatment otherwise it will lead to death. It is important to recognize the signs.  Initially your pet will pant, become restless and then appear distressed.  Often animals are wobbly or disoriented and start to drool excessively.  Eventually the animal’s gum color will change to dark red or purple due to lack of oxygen.

A pet suffering from hyperthermia needs to be removed from the environment immediately and veterinary care needs to be sought.  Move your pet to a cool area and if a fan is available direct this at the animal.  Try to get a rectal temperature and record it.  Place cool wet towels on the animal for evaporative cooling.  Areas that will lead to maximum cooling include the groin, armpits, and the back of the neck.  This can be done while moving the animal to a veterinary facility.

It is extremely important NOT to use ice or cold water to cool the animal.  Cool tap water is recommended.   Do not try to force your pet to take any water, however if your pet is
alert enough to have drink on his/her own that is fine

Severe hyperthermia can lead to multi organ failure and it is important to get your pet to a veterinary facility to be assessed.  Often animals will need intravenous fluids for shock, oxygen therapy and more intensive care depending on the severity of the heat stroke.

Heat stroke is preventable.  Please do not leave your animals in the car even for a few minutes, ensure they have access to shade when outside and on those really hot/humid days plan your walks very early in the morning or late in the evening.  Enjoy the warm weather with your pet, especially after this cold winter we have had, but please be safe.

Brigitte Rudolf, DVM
Bowmanville Veterinary Clinic

Wednesday, July 9, 2014

Pet Food Nutrition: Food Allergies & Food Intolerances


Itch, itch, scratch, scratch. Does your dog lick at his paws, rub his belly on the floor or have chronic
ear infections? Many people assume that dogs and cats with itchy skin have an allergy to ingredients in their food – but actually food allergies in pets are less common than environmental allergies to pollens, molds or dust mites. It can be tricky to differentiate environmental allergies (termed atopic dermatitis) from food allergies, but sometimes atopic dermatitis can present as skin conditions that occur seasonally, while food-allergies are more typically year-round (although not all animals follow these patterns).

Some cats and dogs present with diarrhea that resolves with a change in diet. In these cases, it is more likely that the animal is responding to differences in fat, fibre and digestibility of the food, rather than to a specific ingredient. In fact, “adverse food reactions” can be divided into two categories: food allergies and food intolerance.

  • Food allergy involves an immune-response to specific proteins in the food. Signs can include gastrointestinal signs (vomiting, diarrhea) or – more commonly – skin problems (itching, redness, infections). 
  • Food intolerances do not involve the immune system, and can contribute to gastrointestinal symptoms or – less commonly – skin issues. An example of food-intolerance includes lactose-intolerances, which rarely occurs in dogs and cats, but is common in humans.
How can we diagnose food allergies? 

A strict elimination diet is a good way to reliably diagnose a food allergy or intolerance. The new diet needs to be fed exclusively for 6-10 weeks (with no additional treats, table scraps, rawhides or dental chews), then the animal can be re-challenged with the original diet.

Choosing an elimination diet can be difficult. Exotic ingredients such as lamb, duck and venison are not always good, especially if a dog has been exposed to these ingredients in the past. Unfortunately many pet foods are introducing new and exciting ingredients that sound healthy, which actually complicate matters when trying to rule-out food allergies. 
Finding novel ingredients requires a thorough diet history – including all pet foods, treats, table-scraps, etc. It is important to find novel meat and carbohydrate sources, as carbohydrates can contain allergens as well. A proper elimination diet should contain one protein and one carbohydrate source, plus all the vitamins and minerals required to make the diet complete and balanced.

An alternative option to novel ingredient diets is a hydrolized diet. These diets contain proteins that have been chemically or enzymatically hydrolyzed to reduce them to a smaller size that is less likely to trigger an allergic reaction.

Many over-the-counter pet foods boast the benefits of their novel protein diets meant for food allergies. However, in many cases these diets still contain more than one protein and carbohydrate source, either intentionally or through unintentional contamination from other food lines made in the same manufacturing plant. A true hypoallergenic diet should be created in a facility with strict cleaning protocols, and should always be the first diet manufactured to decrease the risk of contamination. Furthermore, hydrolized diets are not available in over-the-counter recipes. It is possible to use over-the-counter diets as a management diet once a food-allergy is diagnosed, but should not be used during the strict elimination diet period to diagnose a food allergy.

What about grain-free or gluten-free diets?

While there has been a lot of marketing talk lately regarding a movement to grain-free options for dogs and cats, in reality grains are less common causes of allergies than animal products. The most commonly reported food allergies in dogs are beef, dairy, wheat, chicken and egg; in cats beef, dairy and fish are more common culprits. See our next blog in the nutrition series for more about grain-free diets.

In humans there are medical conditions (e.g. celiac disease) that cause people to be sensitive to gluten, a protein portion of some plants. It is currently a popular trend towards pet-foods labelled as gluten-free. However, gluten-sensitivity has only been reported in a small, related family of Irish Setters, and never in cats. There is no evidence to support that gluten-free diets have any health benefit in the majority of dogs and cats.


While food allergies do occur in dogs and cats, environmental allergies and food intolerances are more commonly the causes of skin and gastrointestinal problems. If you are concerned about the possibility of food allergies for your pet, you need to consider a proper food-allergy diet trial done under the supervision of your veterinarian.
Vanessa Tonn, DVM
Bowmanville Veterinary Clinic