As we mentioned above, it is the urobilin compound that is responsible for making pee yellow. If a Boxer dog is dehydrated, there will be a higher concentration of urobilin along with what water is in the kidneys.
As this liquid travels to the bladder and is released, it will then be a very dark yellow color that some describe as amber or even light orange.
Even if a Boxer laps at his water throughout the day or drinks up well after a walk, it's easy for a dog to be slightly dehydrated. Just a 1 to 5% decrease in body fluid is a mild dehydration that can cause urine to be dark. The puppy or dog may or may not have other symptoms such as acting tired, slightly sunken in eyes, bad breath, constipation and/or trouble focusing.
In regard to how much water a Boxer dog needs
, this does vary quite a bit depending on activity level and air temperature. However, the general guideline is 1.62 cups for each 10 pounds of body weight. This amount can be up to 30% more if the dog is very active or on hot summer days when he loses a lot of perspiration via panting.
If there are no other signs such as painful urination or an odd smell, if a Boxer dog has very dark yellow urine this can often be resolve by encouraging the consumption of more water.
While most dogs will not drink on cue making sure that the bowl is cleaned each day, ensuring that water is fresh and cool and offering fruit hat is high in water content (fresh or frozen watermelon or strawberries have over 90% water and mango, oranges and pear slices have over 80% water) can help keep your Boxer hydrated. It can also help to bring water with you when you take your Boxer out for a walk or to the park instead of assuming he will drink enough upon returning home.