Watarai S, Koiwa M
The Laboratory of Veterinary Immunology, Division of Veterinary Science, Graduate School of Life and Environmental Sciences, Osaka Prefecture University, 1-1 Gakuen-cho, Naka-ku, Sakai, Osaka 599-8531, Japan.
J Dairy Sci. 2008 Apr;91(4):1458-63. doi: 10.3168/jds.2007-0406.
The effect of activated charcoal containing wood vinegar liquid (Nekka-Rich) on Cryptosporidium parvum was evaluated in vitro and in vivo. First, the adsorption of C. parvum by the activated charcoal component of Nekka-Rich was examined. When mixed, C. parvum oo-cysts were effectively adsorbed by activated charcoal. Next, the effect of the wood vinegar liquid component of Nekka-Rich was assessed. Wood vinegar liquid had an antiprotozoan activity against C. parvum oocysts. Finally, the anticryptosporidial effect of Nekka-Rich was evaluated in calves experimentally infected with C. parvum. Six neonatal calves at 7 d of age were orally infected with 1 x 10(5) oocysts of C. parvum. When diarrhea was observed (on d 3 after the experimental infection), 3 calves received a milk replacer containing 10 g of Nekka-Rich at 8-h intervals for 4 consecutive days, and 3 control calves were given a milk replacer without Nekka-Rich at 8-h intervals for 4 consecutive days. Calves fed milk with Nekka-Rich showed recovery from diarrhea 1 d after the start of treatment. Significantly less fecal excretion of C. parvum oocysts was observed 1 d after treatment in calves fed Nekka-Rich. On d 2 from the beginning of treatment with Nekka-Rich (on d 5 after the experimental infection), oocysts were not isolated from fecal samples. On the other hand, nontreated control calves developed severe diarrhea, and fecal excretion of oocysts was consistently observed. Calves in both groups were killed for collection of samples, which were subjected to scanning electron microscopy. Scanning electron microscopy revealed adherence of C. parvum oocysts to the intestinal epithelial surface of nontreated control calves, whereas a lack of C. parvum adhesion was observed in calves fed Nekka-Rich. These results suggest that Nekka-Rich would be useful for the treatment of cryptosporidiosis in neonatal calves.
评估了含木醋液的活性炭（Nekka-Rich）对微小隐孢子虫的体内外作用。首先，检测了Nekka-Rich的活性炭成分对微小隐孢子虫的吸附作用。混合后，微小隐孢子虫卵囊被活性炭有效吸附。接着，评估了Nekka-Rich的木醋液成分的作用。木醋液对微小隐孢子虫卵囊具有抗原生动物活性。最后，在实验感染微小隐孢子虫的犊牛中评估了Nekka-Rich的抗隐孢子虫作用。6头7日龄新生犊牛经口感染1×10⁵个微小隐孢子虫卵囊。当观察到腹泻时（实验感染后第3天），3头犊牛连续4天每隔8小时接受含10 g Nekka-Rich的代乳品，3头对照犊牛连续4天每隔8小时接受不含Nekka-Rich的代乳品。饲喂含Nekka-Rich牛奶的犊牛在治疗开始后1天腹泻症状缓解。饲喂Nekka-Rich的犊牛在治疗后1天，微小隐孢子虫卵囊的粪便排泄量显著减少。在开始用Nekka-Rich治疗后的第2天（实验感染后第5天），粪便样本中未分离到卵囊。另一方面，未治疗的对照犊牛出现严重腹泻，且持续观察到卵囊的粪便排泄。两组犊牛均被处死以采集样本，进行扫描电子显微镜检查。扫描电子显微镜显示，未治疗的对照犊牛的微小隐孢子虫卵囊附着于肠上皮表面，而饲喂Nekka-Rich的犊牛未观察到微小隐孢子虫的附着。这些结果表明，Nekka-Rich对新生犊牛隐孢子虫病的治疗可能有效。
