It's important to note that intelligence in dogs can be measured in various ways and can depend on the specific tasks or abilities being assessed. There's no definitive "smartest" dog breed, but certain breeds are often recognized for their high levels of intelligence and ability to learn quickly.

The Border Collie is often regarded as one of the most intelligent dog breeds. They are known for their exceptional herding skills and the ability to understand and follow complex commands. They have a strong work ethic and excel in various dog sports and activities that require problem-solving and agility.

Other breeds that are frequently considered intelligent include the Poodle, German Shepherd, Golden Retriever, and Labrador Retriever. These breeds have shown remarkable aptitude in various roles, such as working dogs, service dogs, and search-and-rescue operations.

However, it's important to remember that individual dogs can vary widely within a breed, and intelligence isn't the only factor to consider when choosing a dog. Each dog has its unique strengths and characteristics, and a dog's intelligence may not necessarily correlate with its suitability as a pet or companion.

It's not accurate or fair to label any specific dog breed as "least intelligent." Intelligence in dogs can be measured and perceived in various ways, and it's important to consider that different breeds have been bred for different purposes.

Additionally, a dog's behaviour and perceived intelligence can be influenced by factors such as training, socialization, and individual temperament. What might be seen as a lack of intelligence in one dog could actually be a result of insufficient training or communication.

Rather than categorizing breeds as more or less intelligent, it's more helpful to recognize that each breed has its own unique strengths and characteristics. All dogs can excel in various areas, whether it's companionship, working, or other roles, and each individual dog has its own personality and potential.