Protein nutrition of underfed beef cows suckling two calves was studied during early lactation using Hereford x British Friesian cows. Feeding the cows with white fish-meal in each of the three years produced calves with a high growth rate (0,97k g/day).T he use of either groundnutm eal or soyabean meal gave a response which was less than that obtained with fish-meal. lt would seem that the more undegradable the protein source, the greater is the response in calf growth rate. The change in weight loss altered and could be related to a change in the nature of weight loss, from mainly fat tissue to less protein and water.Proteienvoeding van ondervoede vleisbees koeie wat twee kalwers laat suip is ondersoek gedurende vroed laktasie deur gebruik te maak van Hereford x Britse Frieskoeie. Die voer van die koeie net uit vismeel in elk van die drie jare het kalwers geproduseer met 'n hoe groeitempo (0,97 kg/dag). Die gebruik van grondboontjiemeeol f sojaboontjiemeehl et 'n kleiner respons as di6 met vismeel tot gevolg gehad. Skynbaar is die respons in kalf groeitempo groter, hoe moeiliker afbreekbaard ie protel'enbronis . Die veranderingi n gewigsverlies het verander en kon in verband gebring word met die verandering in die aard van die gewigsverliesv, an hoofsaaklik vetweefsel na minder protelen en water.Keywords: Underfed beef cows, two calves, undegradable protein