Welcome to Just Answer. My name is Jane. I have been involved professionally with dogs in the healthcare and behavioral fields for over 20 years. I’ve worked as a Vet Assistant and Behaviorist and have extensive experience in dog reproduction, as a breeder, for even longer than that.. Canine behavioral issues and training are also my specialties. It will be my pleasure to work with you today.
You really don't have time to teach him not to howl so your best bet at this point is to get a bark collar. They have both citronella spray models and shock models. They do have to be fit correctly to work and if he is a long haired dachshund, the are where the contacts hit will need to be cut short. Howling will trigger the correction with a bark collar. Whining does not set off the correction, so he may switch to a whine instead.
You can also teach him a quiet command. As crazy as this sounds you may wish to teach the pup the speak or a howl command and then the quiet command. It seems easier to teach the quiet command after the dog has learned the speak command. The following site explains teaching speak and quiet commands.
Clicker training also provides an interesting technique for stopping excessive barking which you can read about here:
I would start training even though it might not be effective for this cycle, it will help with the next one. The collar should stop the howling from being too much of a problem.
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