For the isolation of human peripheral blood mononuclear cells (PBMCs) Nycoprep™ 1.077 was introduced as an alternative medium to Lymphoprep™. It comprises 14.1% (w/v) Nycodenz® (which is non-ionic), 0.44% (w/v) NaCl and 5 mM Tricine-NaOH, pH 7.0, and no polysaccharide. 

Both Lymphoprep™ and Nycoprep™ 1.077 have been used for isolating PBMCs from ruminant blood and it seems that the density of PBMCs from ruminants is closer to that of human PBMCs, compared to those from experimental animals such as rodents. This OptiPrep™ Application Sheet describes two methods for the isolation of PBMCs from ruminants. 

Protocol A describes the familiar strategy of sedimentation on to a density barrier, while Protocol B presents a strategy in which the density of whole blood is adjusted to a value just greater than that of the PBMCs, which allows them to float to the surface. 

Although this flotation technique was developed for human blood, it also seems to be rather broadly applicable to the blood of many species. Protocol B was devised for bovine blood, but it is almost certainly applicable to the blood of other ruminants and probably horses