In the present assay endogenous levels of GH in yak plasma were determined using bovine GH standards.
Therefore it was necessary to carry out the test for parallelism between bovine GH standards used and
different volumes of yak plasma, containing higher concentrations of endogenous GH. The high degree of
parallelism plotted from hormone values obtained from serial dilutions of a blood sample from yak containing
high GH, and the standard curve of bovine GH (Fig. 4) indicates considerable homology between yak GH and
bovine GH used in the assay