Thanks for that information. You still didn't let me know if he was destroying things inside when left alone in the house. You could go ahead and get him neutered and keep sending him to daycare as one solution. However, there are other ways of helping with separation anxiety.
The first thing is to take your dog for a nice long walk before you leave, preferably 30 minutes or long. Make it a long, quick paced walk to tire your boy out. Don't just let him walk casually to eliminate. Make it a quick fast walk allowing him time to casually look around about halfway through.
Second is to use a low-key approach to leaving the house. Ignore your dog before you leave and after you come home for at least 5 minutes or more. If your house is like mine in the morning everyone is running around getting ready to leave. This has the dog in an excited mood and then suddenly he is alone. If this is the case, put him away from everyone, say in a bathroom until the frenzy is over.
You can provide him with small stimulating toys or toys that you can fill with treats. Kongs are a good choice and you can fill them with peanut butter or yogurt and freeze it. The give it to him when you leave. If his mouth is busy, it helps keep him from destroying things.
Sometimes leaving a TV or radio on can help a dog with this problem as well. Also remember to not reward a dog's excitement to you with petting and affection or even eye contact. You want to show him nice calm praise when he is being calm. The best way is to crate him. I know he is eliminating in the crate, but if it saves the home from destruction and prevents injury and protects him as well. Another thing that might help is a DAP collar. These use a pheromone to calm a dog. See one here:
Practice putting him in the crate, leaving the house, opening the door immediately and rewarding him with a hot dog treat if he did not scratch, bite and carry one or eliminate This teaches him that you leave but come back quickly. Once he seems to not do anything when you initially leave, lengthen the time he must be quet for you to come back in. Change the time as well. Make it 2 minutes one time and 10 mintues another, so he never knows if you are gone for an hour or gone for 2 minutes. It helps him stay calm for longer periods of time, just be sure you reward him when he is good.
Another thing that helps is to do things that might make the dog feel you are leaving and then don't such as putting on your coat or picking up your keys. Or leave without doing those things. This helps remove things that might trigger the dog to become anxious.
These should help his separation anxiety and boredom and help curb his barking. It will not be an overnight cure and will take work on your and your family’s part to be consistent in your interaction with him. Here is a site that also offers idea to combat separation anxiety.
Another option is medication, which is discussed on this site:
You might consider a diaper as well if he'll keep it on or putting him in the yard when you leave as long as he isn't able to escape the house. Many dogs actually enjoy being outside when their owners leave for the day. Try the dap collar along with my suggestions and see how he does.
I hope this information is helpful to you. If you would like any additional information or have more questions please don’t hesitate to press the reply to expert or continue conversation button so I can address any issues you still have . If you do find this helpful, please take this opportunity to rate my answer.