Smith H J
Can J Comp Med. 1978 Jul;42(3):332-9.
Infective Cooperia oncophora larvae were temperature and light conditioned by holding them at various temperatures and daily light intensities for up to 56 days prior to administration to parasite-free calves via stomach tube. The calves were killed either on day 20 or day 21 postinfection. A marked (up to 80.5%) inhibition of development occurred in larvae held at 4 degrees C while little or no inhibition occurred in larvae held at room temperature or in fresh larvae. Marked inhibition also occurred in larvae held at 15 degrees C for 56 days while a low rate of inhibition occurred in larvae held at 17 degrees C for 42 days. Low incidence of inhibition was recorded in two of four calves given larvae held at ambient temperatures of mid-summer while appreciable inhibition of development of larvae occurred in two calves permitted to graze during the second and third week of September in 1975. Temperature conditioning of C. oncophora eggs for 27 days did not result in inhibition of development of infective larvae subsequently cultured from the eggs. Photoperiod or the presence of light did not have any appreciable effect on the development of inhibition of C. oncophora under the conditions of these investigations.
感染性的牛古柏线虫幼虫在通过胃管给予无寄生虫的小牛之前，先在不同温度和每日光照强度下保存长达56天，进行温度和光照预处理。在感染后第20天或第21天宰杀小牛。保存在4℃的幼虫发育受到显著抑制（高达80.5%），而保存在室温下的幼虫或新鲜幼虫几乎没有受到抑制。保存在15℃达56天的幼虫也出现显著抑制，而保存在17℃达42天的幼虫抑制率较低。在1975年盛夏环境温度下保存幼虫后给予的4头小牛中有2头抑制发生率较低，而在9月第二和第三周允许放牧的2头小牛中，幼虫发育出现明显抑制。对牛古柏线虫卵进行27天的温度预处理，并未导致随后从卵中培养出的感染性幼虫发育受到抑制。在这些研究条件下，光周期或光照的存在对牛古柏线虫抑制发育没有任何明显影响。
