Joint FAO/IAEA Division of Nuclear Techniques in Food and Agriculture, Insect Pest Control Laboratory, Vienna, Austria.
Epidemiology, Vectors and Parasites, Agricultural Research Council-Onderstepoort Veterinary Research, Pretoria, South Africa.
Med Vet Entomol. 2021 Mar;35(1):141-146. doi: 10.1111/mve.12473. Epub 2020 Aug 25.
The volume of the blood meal of haematophagous insects will determine the number of infective particles taken up during feeding and may as such denote the minimum dose needed to infect a competent vector. Culicoides midges resort among the smallest of haematophagous vectors and determining and comparing their blood meal volumes may be challenging. Collected Culicoides imicola females were fed on defibrinated bovine blood through a Parafilm® membrane using a Hemotek® system. After feeding, the weight of pools of 10 engorged females was compared to that of 10 unfed females to determine the volume of blood imbibed. After weighing, the pools were homogenized and their absorbance read at 410 nm. Spectrophotometer readings were then converted to blood meal volumes using calibration curves, obtained by the dilution of known volumes of blood used for feeding. Although the mean blood meal volumes determined spectrophotometrically (0.06 μL), differed significantly (P < 0.01) from those obtained by weighing (0.07 μL), the range in blood meal volumes determined spectrophotometrically (0.03-0.08 μL) and by weighing (0.01-0.11 μL) was positively correlated (r = 0.7; P < 0.01). Both methods can be used to determine the blood meal volume.
吸血昆虫的血餐量将决定其在进食过程中摄取的感染性颗粒数量，因此可以表示感染有能力的媒介所需的最小剂量。微小牛蜱是吸血媒介中最小的一种，确定和比较它们的血餐量可能具有挑战性。收集到的微小牛蜱雌蚊通过 Parafilm®膜在 Hemotek®系统上吸食去纤维牛血。吸血后，将 10 只饱血的雌蚊的重量与 10 只未吸血的雌蚊的重量进行比较，以确定所吸食的血液量。称重后，将血池均质化，并在 410nm 处读取其吸光度。然后通过使用校准曲线将分光光度计读数转换为血餐量，该曲线通过稀释用于喂养的已知体积的血液获得。虽然分光光度法确定的平均血餐量（0.06μL）差异显著（P<0.01），但与称重法确定的血餐量（0.07μL）差异显著（P<0.01），但分光光度法确定的血餐量范围（0.03-0.08μL）与称重法确定的血餐量范围（0.01-0.11μL）呈正相关（r=0.7；P<0.01）。这两种方法都可用于确定血餐量。
