Manure evaluation in dairy cows

Sammanfattning: Manure evaluation has been suggested as a cheap, fast and easy method which can give information about the digestibility of the ration, the function of the rumen, where in the gastrointestinal tract the feed is digested and the health of the cow. An experiment was conducted to study how manure evaluation could be used as a management tool in Swedish Dairy farming. Manure was collected from cows on Kungsängen Research Station and from 9 other farms. The manure samples were analysed for dry matter, ash, starch, pH-value and particle size (wet sieved). Also, the consistency of the manure was determined on a 5-point scale and the colour and smell were noticed. Penn State Forage Particle Separator was used for determining the particle size of the roughage. Grain kernels were found in the feces from almost all sampled cow. In 250 g fresh manure the amount was 0-150 kernels. The starch content in the feces was low, in most cases around 1 % of the DM and varied from 0-6 %, even when maize silage was fed. This indicates that Swedish cows utilize their concentrate well. Mucin casts were found in manure from cows that seemed healthy and their occurrence increased during a boost of diarrhea. The pH-value in the feces was in most cases 7.0 or higher (variation 6.2-8.0) and decreased with lower roughage:concentrate ratio in the diet. There was a negative correlation between the pH-value and the starch content in the feces. A high intake of a protein rich silage combined with concentrate low in undegradable protein gave nutritionally caused diarrhea. Very few particles in the feces were greater than 2 cm. This indicated that the cows received enough structural roughage. Penn State Forage Particle Separator was not suitable for evaluating the particle size of Swedish roughage diets based on grass-clover silage.