The invention belongs to the technical field of animal models, and particularly relates to a preparation method for constructing a rat
embryo implantation failure model based on
streptococcus agalactiae. The method comprises the following steps: culturing a
streptococcus agalactiae strain with the number of BNCC336970 by using a
solid culture medium containing
sheep blood, adjusting the concentration of a bacterial solution to 1 * 10 < 8 > CFU / mL, and carrying out vaginal
perfusion on an SPF-grade female SD rat every day for 21 days continuously. And after the
perfusion is finished, the female mouse is mated with the male mouse at the early oestrus stage, the detected
vaginal suppository is marked as the 0.5 th day of
pregnancy, the mouse is killed at the 7.5 th day of
pregnancy, and the model is evaluated by counting the
embryo implantation quantity and detecting the expression level of
endometrial tissue receptivity factors MMP9 and VEGF (
Vascular Endothelial Growth Factor). A clinical
pathogen pathogenic mechanism is simulated through a
genital tract infection way for the first time, and the problem of physiological status deviation caused by traditional
hormone intervention, immune agonists or
genetic engineering methods is solved. The constructed model can stably induce the obvious reduction of the
embryo implantation number and the reduction of
endometrial receptivity, and provides a standardized tool for the
pathological mechanism research of infectious embryo
implantation failure and the screening of therapeutic drugs.