%0 Journal Article
%T Evaluation of energy status of dairy cows using milk fat, protein and urea concentrations
%A Kirovski Danijela
%J Macedonian Veterinary Review
%D 2011
%I Ss.Cyril and Methodius University, Skopje
%X Energy status of dairy cows may be estimated using results for concentrations of fat, protein and urea (MUN) in milk samples obtained from bulk tank or individual cows. Using individual cow milk samples is recommended on dairy farms in our geografical region due to the unhomogenity of cows in the herds in respect to their genetic potential for milk production. Depression of milk fat occurs as a consequence of heat stress, underfeeding of peripartal cows, overfeeding concentrate with reduced ration fiber levels or overfeeding with dietary fat. High milk fat content is usually combined with severe negative energy balance. Nutrition and feeding practices have great impact on milk protein level. A deficiency of crude protein in the ration may depress protein in milk. Feeding excessive dietary protein does not significantly increase milk protein. MUN analyses point out potential problems in feeding program on dairy farm. High MUN values may reflect excessive dietary crude protein and/or low rumen degradable non fiber carbohydrates intake. Also, MUN levels is impacted by heat stress since its value is increased during the summer season. Low MUNs indicate a possible dietary protein deficiency. Additionally, low MUNs concentration may indicate excess in dietary nonstructural carbohydrates. On the bases on the interrelationships between protein and urea concentrations, as well as protein and fat concentrations in individual milk sample, estimation of energy balance of dairy cows may be done more accurately.
%K milk organic components
%K energy status
%K dairy cows
%U http://www.macvetrev.mk/2011-2/EVALUATION%20OF%20ENERGY%20STATUS%20OF%20DAIRY%20COWS%20USING%20MILK%20FAT.pdf