Helwigh A B, Christensen C M, Roepstorff A, Nansen P
Danish Centre for Experimental Parasitology, Royal Veterinary and Agricultural University, Copenhagen.
Vet Parasitol. 1999 Apr 12;82(3):221-34. doi: 10.1016/s0304-4017(99)00007-2.
The aim of this study was to examine interactions between Ascaris suum and Oesophagostomum dentatum infections in pigs with regard to population dynamics of the worms such as recovery, location and length; and host reactions such as weight gain, pathological changes in the liver and immune response. Seventy-two helminth-naïve pigs were allocated into four groups. Group A was inoculated twice weekly with 10000 O. dentatum larvae for 8 weeks and subsequently challenge-infected with 1000 A. suum eggs, while Group B was infected with only 1000 A. suum eggs; Group C was inoculated twice weekly with 500 A. suum eggs for 8 weeks and subsequently challenge-infected with 5000 O. dentatum larvae, whereas Group D was given only 5000 O. dentatum larvae. All trickle infections continued until slaughter. Twelve pigs from Group A and B were slaughtered 10 days post challenge infection (p.c.i.) and the remaining 12 pigs from the each of the four groups were slaughtered 28 days p.c.i.. No clinical signs of parasitism were observed. The total worm burdens and the distributions of the challenge infection species were not influenced by previous primary trickle-infections with the heterologous species. Until day 10 p.c.i. the ELISA response between A. suum antigen and sera from the O. dentatum trickle infected pigs (Group A) pigs were significantly higher compared to the uninfected Group B. This was correlated with a significantly higher number of white spots on the liver surface both on Day 10 and 28 p.c.i. in Group A compared to Group B. The mean length of the adult O. dentatum worms was significantly reduced in the A. suum trickle infected group compared to the control group. These results indicate low level of interaction between the two parasite species investigated.
本研究的目的是考察猪体内猪蛔虫与齿状食道口线虫感染之间的相互作用，涉及蠕虫的种群动态，如回收率、寄生部位和长度；以及宿主反应，如体重增加、肝脏病理变化和免疫反应。72头未感染蠕虫的猪被分为四组。A组每周接种两次10000条齿状食道口线虫幼虫，持续8周，随后用1000枚猪蛔虫卵进行攻击感染；而B组仅感染1000枚猪蛔虫卵；C组每周接种两次500枚猪蛔虫卵，持续8周，随后用5000条齿状食道口线虫幼虫进行攻击感染，而D组仅接种5000条齿状食道口线虫幼虫。所有的微量感染持续到屠宰。A组和B组各有12头猪在攻击感染后10天宰杀，四组中每组剩余的12头猪在攻击感染后28天宰杀。未观察到寄生虫感染的临床症状。攻击感染物种的总虫负荷和分布不受先前异源物种的初次微量感染的影响。在攻击感染后第10天之前，与未感染的B组相比，齿状食道口线虫微量感染猪（A组）的猪蛔虫抗原与血清之间的ELISA反应显著更高。这与A组在攻击感染后第10天和第28天肝脏表面的白斑数量显著多于B组相关。与对照组相比，猪蛔虫微量感染组中成年齿状食道口线虫的平均长度显著缩短。这些结果表明所研究的两种寄生虫之间的相互作用水平较低。
