1) pulmonary edema-a build up of excess fluid in the interstital space between the alveoli and the capillary 2) pulmonary fibrosis-a build up of fibrous tissue in the interstital space 3) pneumonia-a build up of inflammatory fluid and cells in and around the alveoli.
The first day of bleeding is called the first day of heat. The duration of proestrus can vary from as little as 1 day to 21 days. Proestrus is a time of rising estrogen levels preparing the reproductive tract for breeding. Estrus: Is the period of receptivity. Behaviorally it begins the first day the bitch stands.
Small breed dogs typically start having estrus (heat) cycles earlier, at 4-6 months of age, and large breeds typically start later, at 12 to 24 months of age. The estrus cycles vary between each individual dog, average of 7 to 10 days. Some dogs as few as 2 days, some dogs cycle as long as 21 days.*.