Zootechnical compositions

A zootechnical composition comprising a weight increasing amount of (a) a zootechnical composition containing a beta adrenergic of at least one compound selected from the group consisting of a compound of the formula ##STR7## wherein R is selected from the group consisting of hydrogen, cycloalkyl of 3 to 7 carbon atoms, piperidinyl with the nitrogen unsubstituted or substituted by alkyl of 1 to 4 carbon atoms and alkyl of 1 to 8 carbon atoms unsubstituted or substituted by --OH or phenyl or phenoxy and the wavy lines indicate that the 7-OH and 6-NH.sub.2 have the trans configuration and their non-toxic, pharmaceutically acceptable acid addition salts and (b) a zootechnical composition containing a steroid of the formula ##STR8## wherein X is selected from the group consisting of hydrogen, alkyl of 1 to 6 carbon atoms wherein one of the carbon atoms may be replaced by --O-- and acyl of an organic carboxylic acid of 1 to 18 carbon atoms.