부산대학교 도서관

The objective of the study was to survey the dietary cation-anion difference (DCAD) in the concentrates and roughages of preparturient dairy ration in Taiwan. Seventeen concentrates and 15 roughages were collected. The analyzed values of electrolytes (including Na, K, Cl and S) were used to calculate the DCAD value [(Na + K) - (Cl + S)] in milliequivalents per 100 gram of dry matter (meq/100 g). Results showed that CAD values were positive in concentrates, except brewer's grains which contained -3.04 meq/100 g and ranged from - 3.04 to 39.97 meq/ 100 g. Six concentrates contained high CAD value (＞ 25 meq/100 g) which was attributed to high Na (0.59%) and high K (1.18%) concentration. All of the roughages contained positive CAD values and ranged from 6.48 to 46.63 meq/100 g. High CAD values (＞ 25 meq/100 g) of 7 roughage samples were due to high K concentration (2.07%) which was higher than that of the average concentrates (1.18%). The high CAD value of corn silage was attributed to the low S concentration (0.080%). Although most of the concentrate samples did not contain optimal DCAD (-10 meq/100 g) for preparturient dry cows, they contained optimal DCAD (17.5-37.5 meq/100g) for lactating cows with exception of samples from the commercial TMR, growing heifer diet and dry cow diet.