Hi Joy, My name is ***** ***** I’ve been involved professionally with dogs in the health and behavioral fields for over 18 years. I've also been breeding for over 20 years as well. It will be my pleasure to work with you today. Dogs can have what is called a silent heat when the normal signs of a dog being in heat are not present. This includes not having any bleeding
or even a swollen vulva. If you have a male in the house, though, they usually do know if your girl comes into heat even if there are no outward signs. If you have been breeding a long time, then you should be aware of silent heat cycles
. You can read more about it here:http://www.aces.edu/pubs/docs/U/UNP-0052/http://www.pets4homes.co.uk/pet-advice/understanding-silent-heat-in-the-bitch.html There are some medical conditions that cause a dog not to go into heat. They are hypothyroidism
(the most common), hyperadrenocorticism, hypoadrenocorticism, diabetes mellitus
, and cancer. Cocker spaniels are a breed that is prone to hypothyroidism, so you may want to have a thyroid panel run on her. You can read about hypothyroidism here:http://www.thyroid-info.com/articles/dog-hypo.htm If she does have any of these conditions, she really should not be bred. Now if hypothyroidism is ruled out there are certain protocols that are generally done to determine infertility
in the female dog. The following site has a good discussion on the various causes of a dog that isn't cycling through a heat cycle (Persistent Anestrus
). http://www.labbies.com/reproduction2.htm Vets can induce heat cycles but along with that, you have a higher than normal chance of your dog developing a uterine infection and ending up needing to be spayed. 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 positively so I am compensated for my time.