Abstract: An assay for a genetic marker associated with increased milk production is disclosed. Also disclosed are kits for use in connection with the assay and breeding methods that use the assay. The assay centers on finding a genetic marker in a bovine cell (e.g. in the DNA of the cell). The presence of the marker is confirmed by exposing a gene sequence from the cell to a restriction enzyme so as to yield gene fragments of varying lengths. During a separation step there is a separation of some of the fragments from others (such as by using electrophoresis), and there is then a hybridization of a plurality of probes that contain a portion of bovine prolactin sequence to the separated fragments. The probe is radiolabelled. Then, there is a comparison of the results of the hybridization with the hybridization results for a gene sequence known to either have the marker or not have the marker. The assay appears to be of greatest utility in connection with the Carlin-M Ivanhoe Bell Holstein family.

Abstract: Portions of the genetic sequence coding for bovine placental lactogen are isolated and a cDNA variant of a bovine placental lactogen gene is then formed and isolated. Upon cloning of the cDNA gene sequence and culturing of a resulting host, large quantities of bovine placental lactogen can be produced.

Abstract: Portions of the genetic sequence coding for bovine placental lactogen are isolated and a cDNA variant of the bovine placental lactogen gene is then formed and isolated. Upon cloning of the cDNA gene sequence and culturing of a resulting hose, large quantities of bovine placental lactogen can be produced.