Dogs' breakfasts boost search performance, says study
Eating a morning meal increases search accuracy in dogs, a new study suggests.
Researchers at the University of Kentucky tested the search performance of trained dogs after either consuming breakfast or fasting.
The study found the canines searched more accurately 30 minutes after a meal than those that searched when hungry.
Findings from the research by Dr Holly Miller and colleague Charlotte Bender were recently published in the journal Behavioural Processes.
Studies demonstrating that children do better in cognitive exercises when they have eaten breakfast led Dr Miller to "wonder if a breakfast would also improve performance by dogs".
Wild dog wonders
So Dr Miller and Ms Bender tested trained domestic dogs' (Canis familiaris) accuracy when finding hidden food, after either eating a morning meal or completing the task without eating.
To ensure that all dogs had depleted energy levels before the search test began, the dogs were required to exhibit self-control for 10 minutes in a 'sit and stay' exercise.
A previous study by Dr Miller demonstrated that the exertion of self-control depletes dogs' energy levels as well as their ability to perform certain tasks.
The dogs were shown a treat that was subsequently hidden in one of six containers. Dogs that had eaten breakfast 30 minutes beforehand navigated to the treat more accurately than those that hadn't eaten for 12 hours.
"The key finding here is rather simple: breakfast can aid performance by dogs," Dr Miller told BBC Nature.
But is the same true for their wild relatives - the closely related wolves, coyotes and jackals?
"Here is where it gets a bit complicated," she said.A well-balanced diet
When "dogs eat a diet that is rich with carbohydrates [such as commercial dog food], their brains are more dependent on glucose and more affected by fluctuations in glucose levels," explained Dr Miller.
But with a diet of hunted meat, where the carbohydrate level is low but fat content is high, the brain switches to its secondary fuel source of ketone bodies instead of the preferential glucose.
"If these animals are consuming a natural diet, that is not scavenged from the dump, they are probably in a state of ketosis where energy for neural processes does not fluctuate much," Dr Miller explained.
This means that a single small meal may not have a big effect on problem-solving and may make "wolves and coyotes less impulsive and more cautious".
But Dr Miller continued, "When hungry they become less able to control their behaviour and this might be why, when hungry, they are so much more dangerous and unpredictable."