By Dr. Brian M. Zanghi, PhD, MS, Senior Research Nutritionist, Nestle Purina PetCare
Brian and his dog WR Aspen
Do you remember the first sporting dog puppy you brought home and the countless hours and days spent training. Or, perhaps your family dog that you turned into a hunting dog. Do you remember when it all “clicked” for your canine buddy? That feeling of “yes, he’s got it”. More than that, how that dog became a part of your field experience. More than just a sporting dog, he or she was your hunting partner. All those times you were amazed by something they did that demonstrated success. That was a culmination of training, experience, and perseverance during the peak of your hunting buddy’s prime. But, those don’t occur quite as often for many reasons, but possibly because pup is getting a bit older, a bit slower. Regardless, the feelings don’t change and the memories don’t fade. You just want to keep that old partnership going for as long as possible, even if it is not the all day hunt or the 3 day trip…
At what age do you consider your dog old, or in the “senior” category? Is it age, declining health status, reduced level of activity, reduced performance, or maybe loss of senses like sight, hearing or smell? Maybe all or some combination of these? For all of us that have had dogs live to a mature older age know that many of the signs of aging we experience as people, also occur in our canine companions. As you might assume, there are some changes in our dogs that may not be so obvious, but can definitely impact performance in the field and overall health. These can include a decline in the immune fitness to fight off illnesses, slower physical recovery from exercise, some increased oxidative stress, and slower metabolism. You may be asking, “what can I do about it, I can’t stop my dog from aging”. Undoubtedly, we can’t stop anybody or any animal from aging, but what we can do is to help reduce or delay many effects of aging by the food the dog eats and how much it consumes.
The big question is how? Let’s make an analogy using our young, adult hunting dog and “optimizing” its performance. With this scenario, to optimize performance we would like our dog to achieve faster learning during training, stay mentally focused at the end of the hunt, run longer, find more game, recover physically for hunting multiple days, etc., etc. We could have an endless list of “do better”. For this example, how can we get there? We could feed a performance food instead of a maintenance food. We could train and condition all year, instead of the week before opening day. We could feed a performance food all year instead of switching back and forth in the “off-season”, which could contribute to improving preseason conditioning and training. We feed an amount to maintain optimal body condition and keeping body weight stable, instead of the having excess body weight. All of these together can contribute to a feeding/training strategy to optimize performance.
Photo by Katie Behnke
Now let’s address the topic at hand. If you are like many of us with busy lives and an older dog, then you probably cherish the thought of having your canine hunting buddy with you when days afield may be less frequent than you wished. Or maybe your proven field champion just deserves a few more rides on the truck, another retrieve, and a little time to stretch his legs and run a bit behind the younger dogs. To keep our healthy, older hunting companion finding birds and sniffing the autumn breeze in the field, we have to switch our mentality from “optimizing” performance to “maintaining” wellness. We know our mature hunting companion understands the game after many years of training and hunting trips. Therefore, we have to accommodate and focus on promoting the skills of the older dog. Speed and total ground quartered are not so paramount, but mental acuity, retained mobility, and overall health are key to “maintaining” field performance.
Unfortunately, our dogs can not tell us that something is just not the way it used to be. But of course, telltale signs of our pup’s advancing age do start to become apparent at some point. There are several nutritional strategies to consider in helping to keep your older dog active and alert. There are several concepts that are worth discussing and can all contribute to keeping your dog hunting a bit longer, even if it is not the hard charging hunt of his peak days. As mentioned above, feeding amount and body condition can play a big role in an older dog’s wellness and longevity. Nutrition studies have also revealed that targeted nutrients in the diet can promote an improvement in mobility in dogs with arthritis, as well as reduce cognitive decline. Retaining physical and cognitive health and wellness by minimizing the age-related decline can be important factors that contribute greatly to stretching out the number of possible hunting seasons.
Feeding and Health
We would all agree, aging can not be prevented, BUT, health and wellness can be improved! A 14-year study led by Nestlé Purina scientists demonstrated that maintaining dogs (Labrador Retrievers) in lean body condition throughout life extended their healthy years, by 1.8 years for dogs in the study. How did they determine this? The dogs fed to maintain a lead body condition were only fed 25% less than their littermates, who were allowed to consume an adequate amount without being overweight.
There were many amazing things that were learned in this study, but it is worth mentioning one set of details. Treatment of certain chronic health conditions was delayed approximately 2 years in the lean-fed dogs. More specifically, treatment for osteoarthritis was delayed with the reduced feeding portion. In fact, 43 of the 48 dogs on the study were treated for osteoarthritis. However, we found that when half of the lean-fed dogs were started on an osteoarthritis treatment, the mean age was ~ 13.3 yrs old, this was a 3 year delay compared to their littermates, where half had started treatment at an average age of 10.3 yrs old. That alone could be a considerable reduction in associated trips to the veterinarian and possible medication. Regardless of vet costs, which we would undoubtedly do regardless, this means a healthier life into those later years, and possibly several more years in the field.
Photo by Katie Behnke
As I mentioned in Articles 1 and 2 of this series of Sportingdog nutrition articles, regularly assessing your dog’s body condition, particularly in older dogs is very important. It is worth mentioning again here, there are simple things you can evaluate and regularly monitor to ensure that your dog is getting the right amount of food to maintain a healthy weight. The link to a Nestle Purina website will provide easy tips:
Part of the reason why I think this topic is worth elaborating on is because most medium to large sporting breeds will age at a rate that will likely result in their metabolism slowing by age 7 to 8. Even though their body weight may remain fairly unchanged, they will likely experience a shift in body mass tissue distribution. All this means is that they may start to lose muscle mass and gain fat mass around this age, but not necessarily show a change in body weight. In the study with the lean-fed dogs, this effect was also delayed. The obvious benefit here is that retaining muscle tissue is critical for maintaining an active lifestyle and more days in the field.
Reducing Cognitive Decline
One change with our older dog that may or may not be so obvious is brain aging, and is inherently a cornerstone to field performance. For any of us that have spent day after day after day…in the training field teaching and refining our pup’s or young dog’s marking ability, steadiness, sit to flush, all of it…You know it takes a lot of time and effort, as well as continuous reinforcement throughout the year and every year to learn and remember the task. To watch it fade away or be apparently lost with your older dog can be heart wrenching, at best.
Dogs, like people, will experience a natural decline in their ability to remember, learn, and even focus with increasing age. The statement, “you can’t teach an old dog new tricks” is definitely rooted in the reality of aging. But how we minimize this decline can be referred to as healthy brain aging. It always amazes me when I see or hear stories about people living over the age of 100, a common denominator is that they were always very mentally active. To relate this to brain aging health in dogs, studies with beagles have also shown that cognitive performance decline can be reduced by maintaining a physically and mentally stimulating lifestyle. So by continuing to keep that healthy, older dog active, every little bit will help. This can be as simple as walking at heel to reinforce obedience and focus, or going to new parks or fields to experience new sights and smells. There definitely is truth to “use it or lose it” when it comes to brain aging.
Photo by Katie Behnke
Fat for Aging Brain Fuel
Another factor influencing brain aging has to do with nutrition and metabolism, and this is where our dog’s diet can play a role in slowing brain aging. It is not surprising that if our physical metabolism changes later in life, our brain metabolism would also change. One of the things I mentioned in the previous article had to do with blood glucose from body stores of glycogen to promote mental function. In particular, how feeding a performance food could optimize the dog’s body stores of glycogen for this purpose. This is because the brain prefers to use glucose as an energy source for nerve function. But, this is during a time in the dog’s life when it is not a senior.
As aging occurs, there is a shift in how the brain generates energy for nerve function. Therefore, if the food the dog eats does not complement this shift, healthy brain aging would not be optimized. So what exactly happens? Well, glucose becomes less “preferred”, and small fat nutrients called ketones become more efficiently utilized. What are ketones? You probably would recognize these molecules by mentioning that if you were starving, your body would produce ketone molecules for brain energy (ketosis). Or, if you have just started a regimen of the Atkin’s Diet, the first phase is to eat in a way that drives your body to produce ketone molecules. Because we don’t want to starve our older dog or induce them to lose weight, the most appropriate way to get ketones for brain function, is to put ingredients in the food that deliver ketone producing nutrients. More specifically, from nutrients called medium chain triglycerides (MCTs). We all have had our triglycerides checked for heart health and triglycerides are an important fuel for endurance metabolism in people and dogs. So, so we are familiar with what those are, but MCTs are not the same thing. However, as the name implies, MCTs are shorter forms and are more easily digested, absorbed, and metabolized.
Okay, you are asking, “Why do we even care? or Does this even matter?” I say, yes, if you want your older dog to have a reduced rate of memory decline, continue to learn more efficiently at an older age, have better attention performance, and probably most importantly for field performance…better executive function. What is executive function? We know that every trip afield is a new set of encounters, challenges, and distractions for our dogs. They are constantly making cognitive decisions such as, do I urinate on this bush or that one, do I follow that rabbit track or keep looking for grouse, is that an old trail or fresh, or maybe…could I have a treat now, you get the idea. The ability to make decisions and stay focused is paramount in the field. Clearly, this is part of what we see when we think of a dog’s drive and style, and is the culmination of all the training and breeding. But life, and a physically taxing lifestyle, can take its toll, both physically and mentally.
So where to MCTs fit in the picture? MCTs have been studied for a variety of nutritional properties over the years. However, recent studies by Nestlé Purina scientists have determined that dietary MCTs can increase blood ketone bodies after feeding old and senior dogs for increasing brain energy supply. Consequently, these studies also revealed that old dogs fed the MCT diet showed significant cognitive improvements in all areas described above compared to old dogs fed a food without MCTs. Therefore, I guess it can be said that an old dog can be taught new tricks, or at least remember the old ones.
Photo by Katie Behnke
Up to this point, the concepts have focused on our pet that is aging successfully, with no real medical conditions or chronic disease afflictions. Many petowners will know of or had a dog with diseases later in life. Some conditions are show stoppers, like loss of sight or hearing, although surgery is an option for cataracts. These situations are heartbreaking, but those are challenges yet to be overcome by nutritional sciences. Disease states are much more difficult to address with a nutritional strategy, but some can be managed with diet. A couple of examples are conditions like osteoarthritis (OA) and diabetes. Obviously, an arthritic condition can stop a sporting dog in its tracks, literally. But, this doesn’t mean that the dog is relegated to pain meds and a life in the kennel. Of course, this would depend on the degree of severity for any given dog. Again, I am not approaching this from the perspective that a severely arthritic dog will eat a food and miraculously be running miles in the field. More from the perspective of; we all get sore and recover a bit more slowly as we age. We possibly work a hard job or we take on a tough weekend project, and we need a couple over-the-counter pain meds at the end of the day to take the edge off, but that doesn’t mean we can’t and don’t work the next day. Therefore, with this framework in mind, an older dog that moves a bit more slowly, but is otherwise healthy, could benefit from this type of strategy to put a little spark in its step. Remember, we are changing the focus from “optimizing performance” to “maintaining wellness”.
If you feel that your dog could benefit from a diet to improve joint mobility, please discuss and work through these options with your veterinarian, as every situation and extent of the disease state must be considered. Your vet would likely recommend an x-ray to get a better understanding of your dog’s arthritic condition. Particularly, as it relates to retaining an active lifestyle.
If a nutritional approach for treatment is a option, there are a variety of therapeutic foods on the market that are available through your veterinarian and address joint mobility, which could provide noticeable benefits. Skeletal and joint health is achieved with many different nutrients in the diet. You probably recognize that balanced calcium/phosphate ratios are important, as well as glucosamine, chondroitin sulfate, and elevated protein, mentioned above, for strong muscles and bones as well. Another nutrient that may be less obvious for skeletal health is the significant contribution of omega-3 fatty acids in the diet. Yes, proper fat in the diet can play an important role. In dogs, clinical nutrition studies have shown that regular consumption of formulas enriched with the proper types and levels of omega-3 nutrients result in a significant improvement in, not only biological indicators, but also pet mobility within 1 month of feeding. After 2 months of feeding, 88% of the dogs on study had client perceived mobility improvement, based on 146 client owned dogs eating the test food. Although many foods contain varying levels of omega-3s, the therapeutic benefits are likely best achieved by feeding a prescription veterinary diet with enriched levels targeting a joint mobility condition.
To be clear, any nutritional strategy to address OA does not cure the disease, it minimizes related discomfort and could be used in combination with veterinary prescribed mediations to promote overall wellness and joint health. Again, talk with your veterinarian to see if this is right for you and your field companion.
So here is the bottom-line to switching the focus from “optimizing” performance to “maintaining” wellness; be conscientious of body condition and feed to prevent weight gain in the less active senior. Switching to a senior formula will provide high protein and lower fat content to promote lean tissue health and provide a less calorie dense food. There are a multitude of other benefits from higher protein for the senior dog, particularly critical, but not addressed here, that include promoting immune, intestinal, and renal health. You can also maintain cognitive stimulation, provide regular exercise, and feed an MCT enriched diet to help to reduce cognitive decline. Finally, consider optimizing joint health by minimizing OA related discomfort with a prescription joint mobility formula.
Your pup may take a little longer to quarter the field, or take a few more whistles or handling casts to get to the area of the fall, but watching that sparkle in his eye and the tail waging as he brings them back to hand for one more season, are all the reasons why we love being in the field with our dog.
Photo by Katie Behnke
Brian Zanghi, Ph.D.
Nestle Research Center
Nestle Purina Petcare
Figure legend: Dogs at 6 and 10 yrs of age that participated in the nutrition study. Dog on left was in the lean-fed group
Table… To easily compare how these diet types compare relative to some nutritional factors and benefits, see table below.
Performance Formula Senior Formula Joint Health Formula
Ideal age 1 – 9 yrs 7 and older 7 and older
Protein 30% 28% 31%
Fat 21% 14% 13%
Calories (kcal/lb) 2003 1710 1750
High protein/ fat for optimal performance High protein/low fat to promote muscle, while reduce fat mass, MCTs for slowing cognition decline** Higher protein with high omega-3 for optimal joint health***
** MCTs for cognition benefit claim supported by feeding Purina ONE Vibrant Maturity 7+ Senior Formula for promoting a Bright Mind as a dog ages.
*** Joint Health claim supported by feeding Purina Veterinary Diets (PVD) Joint Mobility (JM) formula obtained through veterinary prescription.