Effect of OmniGen-AF® supplementation on uterine involution and fertility in a murine model of endometritis

Clinical endometritis, caused mainly by uterine infection following parturition, effects approximately 40-50% of Holstein dairy cattle. Endometritis causes significant economic loss due to increased parity interval and services to conception. Current diagnostic and treatment options have a relatively low success rate and generally result in further economic loss. The objective of this study was to evaluate the impact of OmniGen-AF®(OG) supplementation on murine uterine involution and fertility following the induction of endometritis. Females fed OG had a trending decrease (p=0.06) in time to first parturition of seven days following induction of endometritis and produced an average of five more pups per litter in the first two litters in comparison to mice fed a control diet (p=0.007, n=10-11). Over a six-month breeding trial, OG fed animals continued to produce larger litter sizes (p=0.046) than control animals. Histological analysis of uteri following a six-month breeding trial revealed that uteri from OG fed mice had a trending decrease in the number of endometrial fibrotic lesions and consistently showed decreased incidence and severity of myometrial vascular fibrosis when compared to control counterparts, indicative of broader development of metritis within control animals. No difference in estradiol-induced proliferation of the epithelia, as quantified by immunohistochemistry for phospho-histone H3, was noted in either the luminal or glandular epithelial compartments between control and OG fed females. OG fed mice uteri had elevated vascular development in the endometrium compared with control fed animals (p=0.03). In summary, OG increased reproductive capacity, presumably through enhanced endometrial repair that included increased vascular development and reduced fibrosis. This research provides novel evidence that feeding OG increases fertility after induction of endometritis and provides preliminary evidence for further studies on the impact of OG feeding as a management option for endometritis in cattle. This work was supported by Phibro Animal Health Corporation.