Table 3. Percentages of controlled internal drug release (CIDR) devices retained, presentation of estrus and gestations summarized for the different groups.

	Number ofanimals	CIDRsretained	Presentation of estrus(P = 0.19)	Gestations(P = 0.0037)
Group A (Control)	50	50 (100%)	48 (96%)	8 (16%)
Group B (rHBPs)	50	50 (100%)	46 (92%)	20 (40%)
Total	100	100 (100%)	94 (94%)	28 (28%)

Group A (Control) = crossbred heifers inseminated with cryopreserved, frozen-thawed sperm without added recombinant heparin binding proteins (rHBPs), i.e., control group. Group B (rHBPs) = crossbred heifers inseminated with cryopreserved, frozen-thawed sperm with added rHBPs, i.e., treatment group.