My 13" 3y/o bitch weighs 18.5lbs...she eats 1/2 to 1 full measuring cup of dry kibble a day. That's it. Her exercise is medium, and she maintains her weight well. 13"s get up to 25lbs sometimes but I'd say 18-22 is about average.
15"'s can get up to 35lbs, usually those are large males at the high end.
Things that can affect food consumption...
*eating stool or other objects like rocks, dirt, etc...many, many Beagles do this and it fills the stomach, stop this and the eating should pick up.
*Heat cycles, in bitches some become hogs (like mine) and some fast...males will fast if there's a female in heat nearby at times.
*Hot weather...many dogs naturally cut down intake of food in hot summer months.
*lack of exercise...if the dog isn't burning calories that makes the metabolism slow and might affect apettite.
*Low Thyroid...found a bit more often lately in Beagles...signs are poor hair coat, possible itchiness, poor keepers (not eating well or not gaining readily), dull eyes, obese sometimes, thin other times.
If you cannot readily SEE the hipbones, ribs, and backbone she is likely not underweight. Cut down snacking if she is, be it on poop or dog treats, whatever. Up her exercise, and get her checked out by a vet for thyroid if any of the other symptoms are present...it's a blood test. Beagles are famous for loving to eat. If she WILL eat people food or special treats but not her food...she is likely just holding out for something better. Good luck!
RWB

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