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.
Some General Rules of Thumb for Canine Estrus. 1  The first estrus cycle usually occurs by age 6-12 months; for some small breeds, as early as 5 months, and for some large and giant breeds, the first cycle may not occur until 14 months of age or older. 2  On average, dogs have two cycles a year.