30 Aug 2022
Mike Davies
Job Title
Image © Роман Самсонов / Adobe Stock
It is generally accepted that a pandemic exists of excessive weight in both cats and dogs in the UK, with surveys suggesting the prevalence rate is 51% in dogs and 44% in cats (Pet Food Manufacturers’ Association, 2015).
However, only 14% of dog owners and 18% of cat owners consider their pet to be overweight; furthermore, despite known health risks associated with being overweight, 31% of pet owners do not believe that overweight pets are at increased risk of developing serious diseases and 35% do not realise they have shorter life expectancy (PDSA, 2021).
Obesity changes many metabolic processes, including reducing metabolic rate (Tvarijonaviciute et al, 2012). Interestingly, apart from revised calorie requirements, the other essential nutrient requirements for obese cats and dogs do not appear to have been determined. The assumption seems to be that they remain proportionally related to energy requirements, the same as normal individuals (National Research Council, 2006).
Good nutrition to prevent obesity in later life starts during pregnancy, as puppies with low birth weights are predisposed to develop obesity in later life (Mugnier et al, 2020; p value = 0.032), with a 70% prevalence of obesity among dogs with low tissue mass birth weight compared to 47% in dogs born with high tissue mass birth weight. Being overweight was also associated with advancing age and in neutered dogs (p value = 0.029 and 0.005 respectively).
The secret to maintaining optimum bodyweight and fat composition is to get owners to understand that being overweight is a serious disorder, and for them to embrace the concept of lifelong weight control through diet and exercise. Failure to comply with veterinary recommendations is the main reason why owners lose control of their pets’ body condition (Porsani et al, 2020)
According to the American Animal Hospital Association (AAHA), compliance and adherence to veterinary advice can be improved by a variety of means (Table 1).
| Table 1. Factors improving adherence with veterinary recommendations (American Animal Hospital Association, 2009) | |
|---|---|
| Factor | Finding |
| Length of appointment | Pet owner data indicates that adherence is high when an appointment lasts more than 10 minutes |
| Written information | Respondents who received written information had higher adherence |
| Follow-up calls | Pet owners who received a follow-up call achieved higher adherence |
| Reminders for ongoing management | Pet owners who received reminders were more compliant than those who did not receive reminders |
| Continuity with the veterinarian | Pet owners who reported seeing the same veterinarian at each visit reported higher adherence |
| Cost of treatment | The cost of treatment did not correlate with adherence |
In its 2009 report, the AAHA documented specific changes in practice that had improved compliance from its report in 2003 (Panel 1).
When practices employed four or more of these good habits, they achieved greater compliance:
Steps that can be taken to control bodyweight and condition throughout life are summarised in Table 2.
| Table 1. Long-term prevention of overweight/obese state (American Animal Hospital Association, 2009) | |
|---|---|
| Action | Methods |
| Set optimum bodyweight |
|
| Maintain optimum body condition score (BCS) |
|
| Strict control of calorie intake |
|
| Modify gene expression for obesity through diet |
|
| Maintain exercise |
|
| Regular weighing |
|
| Regular checking of BCS |
|
| Keep in regular contact with the owner |
|
| Regular full clinical re-examinations |
|
Many key reference texts can be found on the subject of management of obesity in cats and dogs that can be used in practices (Diez and Nguyen, 2006; German and Martin, 2008).
Controlling calorie intake is critical and easy to say, but not so easy to implement. However, steps can be taken, including the use of low calorie and other therapeutic diets, providing small portions, eliminating treats and snacks, or replacing them with main ration. Owners tend to want to fill a bowl, so encourage them to use a smaller bowl.
Body condition score (BCS) should be maintained at just below the midpoint on current BCS charts, and dogs should be kept slightly lean, as this has been shown to prolong lifespan by about 18 months in the Labrador retriever and delay the onset of age-related diseases by two years (Kealy et al, 2002). In that study, none of the Labrador retrievers developed clinical hip arthritis over their lifespan.
However, do not rely on owners to report BCS values accurately because they may underestimate their pet’s size and condition – even when using a validated chart (Teixeira et al, 2020).
In cats and dogs that do become overweight, early intervention is needed to return weight and body fat levels to optimum.
Obese animals have a lower metabolic rate and energy requirements (German et al, 2011), and intake needs to be reduced to 60% of calorie requirement at optimum weight to achieve weight loss. They also have poorer quality of life (German et al, 2012a), as well as shorter life expectancies (Salt et al, 2019).
Only recommend properly formulated diets that are low-calorie dense and high in essential nutrient content, or that have been formulated to modify gene expression to encourage weight loss. Only recommend diets for which clinical trials have proven that they work (Linder and Freeman, 2010; Roudebusch et al, 2008).
Advise owners not to revert to feeding regular foods once optimum bodyweight is reached because twice as much risk exists that they will gain weight again compared to continuing with a weight control diet (German et al, 2012b). Homemade weight loss formulas are unlikely to be complete and balanced when owners are compiling the ration themselves, and cannot be recommended (Davies, 2014).
It is important to maintain optimum bodyweight and BCS throughout life. Owners must be motivated to remain vigilant to identify increasing bodyweight through regular monitoring.
Veterinary practices can play a very important role by educating owners and maintaining contact to reinforce the need to maintain optimum body conditions to prevent the secondary diseases, reduced quality of life and reduced life expectancy that result from obesity.
Mike Davies
Job Title