Conclusions: SENTINEL Flavor Tabs are palatable to dogs.

DOSAGE: SENTINEL Flavor Tabs are available in four tablet sizes in colour-coded packages for oral administration to dogs.

Splitting tablets that are not scored (I don’t believe sentinel is scored) could result in an inadequate dose as the ingredients may not be evenly distributed within the tablet, one dog might get too much of one ingredient and the other dog not enough,etc. So, that is not a good idea. I am a nurse.
Also, you can use the search engine here, to see previous comments.

PRESENTATION: SENTINEL Flavor Tabs are available in four tablet sizes (see Dosage Section), formulated according to the weight of the dog. Each tablet size is available in colour-coded packages of six (6) or twelve (12) tablets which are packaged ten (10) per display carton.

Sentinel for Dogs | Flavor Tablets - 1800PetMeds Sentinel Tablets for Dogs | Pet 360

I decided to write a blog post answering some of the common questions I hear about . Sentinel is different from most other types of flea control products because it comes in the form of a pill rather than a liquid topical that is applied to your dog’s skin. The active ingredients in Sentinel, milbemycin oxime and lufenuron, are absorbed by your dog systemically and remain in the bloodstream for a period of around 30 days. Sentinel tablets should be given with a meal to ensure adequate absorption.Sentinel for dogs is a chewable, beef-flavored tablet given once every 30 days to prevent heartworm infection as well as flea infestations. It can be given to dogs and puppies as long as they are older than 4 weeks and weigh more than 2 pounds. Studies showed no ill effects on puppies whose mother was given three times the normal dose of Sentinel while nursing and pregnant. However, you should consult with your veterinarian on whether or not giving Sentinel to pregnant or nursing dogs is recommended.Sentinel Spectrum gives your dog broad-spectrum protection from dangerous pests. Each chewable tablet contains a combination of milbemycin oxime and lufenuron that work together to protect your dog from pests and parasites for a full month. The active ingredients stop heartworm larvae from developing while killing adult hookworms, whipworms, tapeworm and roundworms. They also stop flea eggs from hatching so the flea life cycle is broken and your pet is protected from reinfestation. The tablets are beef flavored for no hassle dosing. Sentinel is a prescription medication FDA-approved for use in dogs. Sentinel is available as artificial beef flavored (derived from pork and soy protein) chewable tablets. This medication should be given once a month year-round.