What are the methods for processing roughage for dairy cows?

Chopping short   The coarse, hard lower part of the straw should be cut off and discarded, while the upper part of the straw can be cut into 3-4 cm long grass segments, which gives the best feeding results. The daily intake increases by about 2% compared with dry hay.

Grinding   After grinding, straw can be mixed with concentrate feed, which can increase intake and improve digestibility. Grinding roughage can accelerate the rate of feed passage and increase intake. However, grinding roughage or cutting roughage very short will reduce chewing and rumination time, saliva secretion, feed retention time in the rumen, roughage digestibility, the ratio of acetic acid to propionic acid and the pH value in the rumen, and milk fat percentage, which is detrimental to dairy cow health and milk production. Long roughage can maintain the structural layer of rumen contents and stimulate rumen motility, rumination and saliva secretion. Therefore, the diet should contain at least 1/3 long roughage (2-5 cm).

Soaking   Sprinkle chopped roughage or chaff with water or soak it in 0.2% saline solution. After 24 hours, it becomes soft in texture. Then mix it with mixed feed and bran, which can change palatability and increase intake.

Alkali treatment   Cut straw into 3-4 cm lengths, evenly spray 1.6% sodium hydroxide solution onto the straw to moisten it, pile it for a few days, then take it out and feed it directly to cattle.

Calcification method   Soak straw in 1% quicklime or 3% slaked lime milk. About every 100 kg of lime milk can soak 8-10 kg of straw. Take it out after 12-24 hours and feed it directly to cattle. Alternatively, take 100 kg of chopped straw, mix 3 kg of quicklime or 4 kg of slaked lime with 0.5-1.0 kg of salt and 200-250 kg of water, mix well, place it on flat ground or wooden boards for 24-36 hours, and feed it directly to cattle.

Ammoniation treatment   The first is anhydrous ammonia treatment. Adjust the moisture content of the straw to 30%-40%, place a plastic pipe at a height of 0.5 m in the stack for introducing ammonia water. Seal the haystack with 0.5 mm thick plastic film. The time varies with ambient temperature. When the temperature is 2°C, seal for 2-4 weeks. After opening, dry it in the sun and feed it after the ammonia smell disappears. The second is ammonia water treatment. When stacking chopped straw into a pit (silo), evenly spray 3% concentrated ammonia water into the silo at a ratio of 1:1 to the weight of the straw. After filling the pit, cover and seal it tightly with film. The sealing time depends on ambient temperature. Below 5°C requires 8 weeks, 5-15°C requires 4-8 weeks, 15-30°C requires 1-4 weeks, and above 30°C requires 1 week. Then open the silo and dry the straw, and it can be fed. Ammoniation treatment of feed can increase the protein content of roughage by 4%-6%, increase the average daily intake per cow by 16%-60%, and improve the digestibility of straw organic matter. The disadvantage is that ammonia loss is relatively large; about 2/3 of the ammonia escapes after opening the silo.