两种不同兔种对兔疥螨的宿主抗性比较分析。

Comparative analysis of host resistance to Sarcoptes scabiei var. cuniculi in two different rabbit breeds.

机构信息

Department of Parasitology, College of Veterinary Medicine, Sichuan Agricultural University, Wenjiang, 611130, China.

Sichuan Animal Sciences Academy, Chengdu, 610066, Sichuan, China.

出版信息

Parasit Vectors. 2019 Nov 8;12(1):530. doi: 10.1186/s13071-019-3764-5.

DOI:10.1186/s13071-019-3764-5

PMID:31703721

原文链接:https://pmc.ncbi.nlm.nih.gov/articles/PMC6842134/

Abstract

BACKGROUND

Scabies, caused by infestation of the mite Sarcoptes scabiei, is one of the most severe ectoparasitic diseases in rabbits. Scabies seriously affects the commercial rabbit breeding, causing severe economic losses. Host resistance to S. scabiei is an important factor in further development of the rabbit industry. In the present study, we compared the host resistance to S. scabiei var. cuniculi of a new breed of domestic rabbit propagated by the Sichuan Animal Sciences Academy (QiXing rabbit, QX) compared with that of a traditional rabbit breed in the domestic rabbit industry (IRA rabbit, IRA).

METHODS

Both QX and IRA rabbits were experimentally infested with live S. scabiei var. cuniculi mites for 48 h. Then, during the course of four-week experimental infestation period, the body weight of rabbits was recorded every two weeks for calculating body-weight variations in comparison to the non-infested control rabbits. Skin lesions in the foot area were assessed on weekly basis and serum samples were tested weekly for the estimation of changes in the total antibody levels (IgG, IgE and IgM). Moreover, DNA extracted from the blood samples was amplified for analysis of the genetic diversity in the major histocompatibility complex, class II, DQ Alpha (MHC-DQA) gene.

RESULTS

Compared to the IRA rabbits, the QX rabbits showed a significantly higher (P < 0.05) relative body weight gain compared to the non-infested control rabbits and significantly lower (P < 0.05) scores for foot skin lesions and higher levels of IgG, IgE and IgM at weeks 1 to 4, week 2 and week 1 post-infestation, respectively. Furthermore, a polymorphism site at position 103 bp of exon two of MHC-DQA gene and a different gene frequency were found between two rabbit breeds, suggesting the genetic basis for the differential host resistance to the S. scabiei var. cuniculi between two rabbit breeds.

CONCLUSIONS

The QX rabbits showed higher host resistance to S. scabiei var. cuniculi compared to the IRA rabbits at the clinical, immunological and genetic levels. These results provide a reference for the breeding of rabbits with adequately improved and sustained host resistance to scabies in the domestic rabbit industry.

摘要

背景

疥疮是由疥螨引起的一种严重的外寄生虫病，是兔子最严重的寄生虫病之一。疥疮严重影响商品兔的养殖，造成严重的经济损失。宿主对疥螨的抵抗力是兔业进一步发展的重要因素。在本研究中，我们比较了由四川省农业科学院培育的新型家兔品种（七星兔，QX）与国内家兔产业中的传统兔种（伊拉兔，IRA）对兔疥癣的宿主抗性。

方法

将 QX 和 IRA 兔用活的兔疥螨螨感染 48 小时。然后，在为期四周的实验感染期间，每两周记录一次兔子的体重，与未感染的对照兔子相比，计算体重变化。每周评估足部皮肤病变，每周检测血清样本，以评估总抗体水平（IgG、IgE 和 IgM）的变化。此外，从血液样本中提取的 DNA 进行扩增，分析主要组织相容性复合体、Ⅱ类、DQ 阿尔法（MHC-DQA）基因的遗传多样性。

结果

与 IRA 兔相比，QX 兔相对于未感染对照兔的相对体重增加明显更高（P<0.05），感染后第 1 至 4 周、第 2 周和第 1 周，足部皮肤病变评分明显更低（P<0.05），IgG、IgE 和 IgM 水平更高。此外，在 MHC-DQA 基因外显子 2 的 103 bp 位置发现一个多态性位点，两个兔种的基因频率不同，提示两个兔种对兔疥癣的宿主抗性存在遗传基础差异。