Abstract: A microporous material comprises organic macromolecules comprised of first generally planar species connected by rigid linkers having a point of contortion such that two adjacent first planar species connected by the linker are held in non-coplanar orientation, subject to the proviso that the first species are other than porphyrinic macrocycles. Materials in accordance with the invention have a surface area of at least 300 m2g?1, eg in the range 700-1500 m2g?1. Preferred points of contortion are spiro groups, bridged ring moieties and sterically congested single covalent bonds around which there is restricted rotation.

Abstract: A feed supplement for ruminants comprising a gluconeogenic compound, which can be digested in the rumen and a hydrogenated fatty acid, which is rumen inert, is described. One example of such a feed supplement comprises 30% gluconeogenic compounds, by weight and 30% C.sub.14 -C.sub.22 hydrogenated fatty acids by weight, the balance being essentially inert compounds. The feed supplement of the present invention can be used in the treatment of or for the prevention of negative energy or a nutrient imbalance. A method of treating or preventing a nutrient imbalance by administering to a ruminant in need thereof, a daily dosage amount of a composition comprising a gluconeogenic compound, which can be digested in the rumen and a hydrogenated fatty acid, which is rumen inert, for from 10-21 days prior to calving to 21-42 days after calving.