Problems in nutrition of dairy cows and beef cattle are solved in Institute of Animal Science in the long term. Techniques of feeding total mixed rations (TMR) in dairy cows and daily frequency of their feeding are some of the topics which were explored. Solving of nutrition of dairy cows during parturition interval is focused continually, namely during their transitional period. There were achieved an array of results in field of milk quality namely in improving of fatty and amino acids concentration in milk. Also effects of protected methionine were examined in several experiments. Recently, the survey of the effect of dried corn slops and protected lysine supplement on milk performance is in progress. Next experiments which are concerned with problems of length of dried period and feeding techniques during that period are made up methodically. The effect of using of oil seeds in feeding rations on fatty acids level in beef meet and on growth intensity of beef cattle was examined, too.