Fimbriae (common pili) and flagella on the surface of bacterial cells. Left: dividing Shigella enclosed in fimbriae. The structures are probably involved in the bacterium's ability to adhere to the intestinal surface. Right: dividing pair of Salmonella displaying both its peritrichous flagella and its fimbriae.
Relaxin's peak is reached during the 14 weeks of the first trimester and at delivery. It is known to mediate the hemodynamic changes that occur during pregnancy, such as increased cardiac output, increased renal blood flow, and increased arterial compliance.
What can we dig up for you? A blood test is now available that detects pregnancy in the bitch by measuring levels of a hormone called relaxin. This hormone is produced by the developing placenta following implantation of the embryo, and can be detected in the blood in most bitches as early as 22-27 days post breeding.