Environmental Health and Ecological Science Department, Ifakara Health Institute-Bagamoyo Office, P.O. Box 74, Bagamoyo, Tanzania.
School of Life Sciences and Bioengineering, The Nelson Mandela African Institution of Science and Technology (NM-AIST), P.O. Box 447, Arusha, Tanzania.
Parasit Vectors. 2024 Jul 6;17(1):289. doi: 10.1186/s13071-024-06345-y.
The current rise of new innovative tools for mosquito control, such as the release of transgenic mosquitoes carrying a dominant lethal gene and Wolbachia-based strategies, necessitates a massive production of mosquitoes in the insectary. However, currently laboratory rearing depends on vertebrate blood for egg production and maintenance. This practice raises ethical concerns, incurs logistical and cost limitations, and entails potential risk associated with pathogen transmission and blood storage. Consequently, an artificial blood-free diet emerges as a desirable alternative to address these challenges. This study aims to evaluate the effects of a previously formulated artificial blood-free diet (herein referred to as BLOODless) on Anopheles gambiae (An. gambiae s.s.; IFAKARA) gonotrophic parameters and fitness compared with bovine blood.
The study was a laboratory-based comparative evaluation of the fitness, fecundity and fertility of An. gambiae s.s. (IFAKARA) reared on BLOODless versus vertebrate blood from founder generation (F) to eighth generation (F). A total of 1000 female mosquitoes were randomly selected from F, of which 500 mosquitoes were fed with bovine blood (control group) and the other 500 mosquitoes were fed with BLOODless diet (experimental group). The feeding success, number of eggs per female, hatching rate and pupation rate were examined post-feeding. Longevity and wing length were determined as fitness parameters for adult male and female mosquitoes for both populations.
While blood-fed and BLOODless-fed mosquitoes showed similar feeding success, 92.3% [95% confidence interval (CI) 89.7-94.9] versus 93.6% (95% CI 90.6-96.6), respectively, significant differences emerged in their reproductive parameters. The mean number of eggs laid per female was significantly higher for blood-fed mosquitoes (P < 0.001) whereas BLOODless-fed mosquitoes had significantly lower hatching rates [odds ratio (OR) 0.17, 95% CI 0.14-0.22, P < 0.001]. Wing length and longevity were similar between both groups.
This study demonstrates the potential of the BLOODless diet as a viable and ethical alternative to vertebrate blood feeding for rearing An. gambiae s.s. This breakthrough paves the way for more efficient and ethical studies aimed at combating malaria and other mosquito-borne diseases.
当前，新型创新蚊虫控制工具（如携带显性致死基因的转基因蚊子释放和基于沃尔巴克氏体的策略）不断涌现，这使得昆虫饲养室需要大规模生产蚊子。然而，目前实验室饲养依赖脊椎动物血液来生产和维持蚊子的卵子。这种做法引发了伦理问题，同时也存在后勤和成本方面的限制，以及与病原体传播和血液储存相关的潜在风险。因此，一种无血的人工饲料成为解决这些挑战的理想替代方案。本研究旨在评估先前制定的无血人工饲料（简称 BLOODless）对冈比亚按蚊（冈比亚按蚊 s.s.；IFAKARA）的生殖参数和适应性的影响，并与牛血进行比较。
本研究采用实验室比较评估的方法，对从创始代（F）到第 8 代（F）的冈比亚按蚊 s.s.（IFAKARA）在 BLOODless 和脊椎动物血液（对照组）饲养下的适应性、繁殖力和生育力进行评估。从 F 代中随机选择 1000 只雌性蚊子，其中 500 只喂食牛血（对照组），另 500 只喂食 BLOODless 饲料（实验组）。喂食后检查每只雌性的取食成功率、产卵数、孵化率和化蛹率。用成年雄性和雌性蚊子的寿命和翅长作为适应性参数进行测定。
尽管血液喂养和 BLOODless 喂养的蚊子取食成功率相似（分别为 92.3%[95%置信区间（CI）89.7-94.9]和 93.6%[95% CI 90.6-96.6]），但它们的繁殖参数存在显著差异。血液喂养的蚊子平均产卵数显著更高（P<0.001），而 BLOODless 喂养的蚊子孵化率显著更低（比值比[OR]0.17，95% CI 0.14-0.22，P<0.001）。两组蚊子的翅长和寿命相似。
本研究表明，BLOODless 饲料作为一种可行且符合伦理的替代脊椎动物血液喂养的方法，用于饲养冈比亚按蚊 s.s. 这一突破为开展更高效和符合伦理的研究，以抗击疟疾和其他蚊媒疾病铺平了道路。
