The invention comprises hydrazines of the general formula R1NHCSNHNHCSNR2R3 wherein of the symbols R1 R2 and R3, one stands for an alkyl radical of not more than 4 carbon atoms or for an alkenyl radical and, of the remaining two symbols, one stands for hydrogen or for an alkyl radical of not more than 4 carbon atoms, an alkenyl radical, an aralkyl radical optionally substituted by halogen, methyl or methoxy radicals, a cycloalkyl radical, an alkoxyalkyl radical or an alkylthioalkyl radical and the other stands for an alkyl radical of not more than 4 carbon atoms, an alkenyl radical, an aralkyl radical optionally substituted by halogen, methyl or methoxy radicals, a cycloalkyl radical, an alkoxyalkyl radical or an alkylthioalkyl radical or wherein R1 stands for an alkyl or alkenyl radical, R2 stands for hydrogen and R3 stands for a carbethoxy radical, provided that when R2 stands for hydrogen, R1 and R3 do not both stand for the methyl, ethyl or allyl radicals and, when R1 stands for the methyl radical and R2 for hydrogen, R3 does not stand for the allyl radical and the preparation thereof by p  reacting an isothiocyanate of the formula R1NCS (or the corresponding dithiocarbamate derivative R1NHCSSR5, where R5 stands for a methyl or ethyl radical, providing R1NCS under the conditions of the reaction) with a semicarbazide of the formula H2NNHCSNR2R3 or (wherein R1 and R2 stands for the same radical and R3 stands for hydrogen) by reacting an isothiocyanate of the formula R4NCS, wherein R4 stands for an alkyl radical of not more than 4 carbon atoms or for an alkenyl radical, and hydrazine.  a -Methylallylisothiocyanate is prepared by reacting g -methylallyl bromide with ammonium thiocyanate.  4 : 4-Di-n-propylthiosemicarbazide is prepared from carbon disulphide di-n-propylamine and sodium chloroacetate which are reacted to yield di-n-propylthiocarbamylthioglycollic acid and reacting this with hydrazine.  The Provisional Specification in addition relates to thiocarbamoylhydrazines of the above formula wherein R1 R2 and R3 are hydrocarbon radicals optionally substituted e.g. by halogen, alkoxy or nitro groups.ALSO:Animal feedstuffs and premixes contain one or more this carbamoylhydrozines of the general formula R, NHCSNHNHCSNR2R3 wherein of R1, R2 and R3 one represents an alkyl group containing up to 4 carbon atoms or an alkenyl group and of the other two one represents a hydrogen atom, an alkyl group containing up to 4 carbon atoms, an alkenyl group, an aralkyl group (optionally substituted by halogen atoms, methyl or methoxy groups) a cycloalkyl, an alkythioalkyl or an alkoxyalkyl group and the other represents an alkyl group containing up to 4 carbon atoms, an alkenyl group, an aralkyl group (optionally substituted by halogen atoms, methyl or methoxy groups), a cycloalkyl, an alkoxyalkyl or an alkylthioalkyl group or or when R1 is an alkyl or alkenyl, and R2 is hydrogen R3 is a carbethoxy radical.  Premixes preferably contain 0.1-25% and feedstuffs 0.001-1% by weight of the active ingredient.ALSO:Pharmaceutical and veterinary compositions comprise at least one hydrazine derivative of the formula R1NHCSNHNHCSNR2R3 (wherein of the symbols R1 R2 R3, one stands for an alkyl radical of not more than 4 carbon atoms or for an alkenyl radical and of the remaining two symbols, one stands for hydrogen or for an alkyl radical of not more than 4 carbon atoms, an alkenyl radical, an aralkyl radical optionally substituted by halogen atoms, methyl or methoxy radicals, a cycloalkyl, an alkoxyalkyl or an alkylthioalkyl radical and the other stands for an alkyl radical of not more than 4 carbon atoms, an alkenyl radical, an aralkyl radical optionally substituted by halogen atoms, methyl or methoxy radicals, a cycloalkyl, alkoxyalkyl, or alkylthioalkyl radical or wherein R1 stands for an alkyl or alkenyl radical R2 stands for hydrogen and R3 stands for a carbethoxy radical, provided that when R2 stands for hydrogen, R1 and R3 do not both stand for the methyl, ethyl or allyl radical and when R1 stands for the methyl radical and R2 for hydrogen, R3 does not stand for the allyl radical) in admixture with non-toxic pharmaceutically acceptable inert diluents or carriers. The compositions may be in the form of tablets, capsules, solutions or suspensions in aqueous or in non-toxic organic solvent media, dispersible powders suitable for the preparation of liquid suspensions for oral or parenteral use. Examples are given of the preparation of tablets and suspensions in water.