Proteolytic enzymes, such as collagenase, have been used successfully in hydrolyzing collagen present in postpartum uteri in several species, including the cow, in in vitro studies. Little work has been done using collagenase on the placentome from a near-term cow uterus. Working on the theory that the bovine fetal membranes are retained due to a lack of collagen breakdown within the placentome, an in vitro study was done using low placentomes and the proteolytic enzyme bacterial collagenase (Cl. Histolyticum).
Sections of near-term cow placentomes, taken immediately after slaughter were incubated in buffered saline with various concentrations of enzyme over different time periods. Collagen breakdown was determined by measuring hydroxyproline which is found almost exclusively in collagen and nitrogen from the incubation supernatants.
Results indicate that very low concentrations of collagenase do not cause a significant liberation of hydroxyproline or nitrogen (P\u3c.05). At the low concentrations, there was no difference in the amount of hydroxyproline or nitrogen released over time (P\u3c.01). The high concentrations showed a significant amount of hydroxyproline and nitrogen released due to concentration and due to incubation time period (P\u3c.05; P\u3c.01) respectively.
These results suggest that it is possible to break down collagen in the near-term cow placentome, and possibly in cases of RFM, but a sufficiently high concentration or high enzyme to substrate ratio must be utilized
