In some cases yes. In general polyclonal antibodies have wider species cross-reactivity than murine monoclonal antibodies. The species cross-reactivity of an antibody depends on factors such as the evolutionary distance of the test species from the host animal and the species from which the antigen was purified as well as the application in which the antibodies are being used. Some proteins are more highly conserved among mammalian species and antibodies raised to such proteins tend to demonstrate a greater degree of species cross-reactivity. For example, the goat anti-human von Willebrand Factor (vWF) has been shown to cross react with vWF from rabbit and rat plasma while the sheep anti-human FVIII seems to react with human FVIII only. Wherever possible we have tried to purify the antigen from the target species and to make antibodies to these protein antigens. DiaPharma and Affinity Biologicals are committed to providing the hemostasis researcher with a complete line of immunoassay tools for human and animal research. Information from historical lots on typical species cross-reactivity for the different antibodies in our product line is available in a table in the Technical Support section. This is an ongoing process so if you can't find what you're looking for please contact us.