|Budget Amount *help
¥3,200,000 (Direct Cost : ¥3,200,000)
Fiscal Year 1999 : ¥600,000 (Direct Cost : ¥600,000)
Fiscal Year 1998 : ¥2,600,000 (Direct Cost : ¥2,600,000)
We performed a reappearance test on the occurrence of white diarrhea in calves after an additional supply of corn silage was given to cows fed with a low starch diet , which was surmised to be one of the causes of the development of white diarrhea in calves. We selected five Japanese Black cows immediately after delivery and their offspring, and followed the gastric juices, blood, and milk of cows and blood and feces of calves up until the development of white diarrhea, measuring the amounts of diet intake and of lactation each day. All the offspring of the selected cows developed white diarrhea 5-7 days after the corn silage began to be fed to the cows. A slight change was found in the feces of calves 1-3 days after the start of corn silage feed. If we consider this as first day of antecedent sign occurrence, the number of large- and medium-sized protozoan in the rumen juice increased around that day. The concentration of Mg, Ca, and long-chain saturated fatty acids in milk increased
and the pH level and the constitution of fatty acids in milk became unstable on the day this antecedent sign occurred. Simultaneously, an increase in TG in blood began in the calves, which seemed to be caused by retention of milk contents due to formation of fatty acidic salts in the calves' intestinal canals. The day before the onset of white diarrhea, the number of large- and medium-sized protozoa in the rumen of the cows began to decrease while small-sized protozoa increased markedly. The serum levels of phospholipids (PL) and BUN increased in accordance with this. On the day of white diarrhea onset, dramatic temporary changes occurred in the contents of the blood (TG, PL, Glucose, and BUN) and milk (fat content, fatty acid constitution, and pH) of the cows, because of a transient increase in digestion and absorption by a large amount of microorganisms. It was presumed that white diarrhea occurred in calves that had ingested this milk, excreting it as lienteric fatty stools.
These findings showed that a change in the condition of the rumen caused by the trigger of feeding corn silage induces a change in the fat of cow blood. Thus calves that ingest milk from such cows develop what is known as "white diarrhea caused by dam's milk calves." Less