母体供应在发育较短的无脊椎动物中尤为重要,因为必须为发育中的胚胎提供大量能量储备。在这种情况下,本研究的目的是在直接发育的水生无脊椎动物中分析温度对雌性生化成分的影响以及对成熟卵巢的储备分配,这决定了鸡蛋的质量。一种十足的甲壳类动物,淡水虾Neocaridinadavidi,作为实验模型。将新孵化的幼鱼暴露于28°C或33°C。雌性显示出成熟的卵巢,并在28°C产卵(对照卵生雌性),但是在33°C时没有发现产卵的雌性。经过200天的时间,33°C的女性中有一半被转移到28°C,在那里,它们迅速显示出成熟的卵巢并产卵(转移了产卵的雌性)。处死产卵的雌性和在28°C下不产卵的雌性(对照非产卵的雌性)和在33°C下产卵的雌性(高温非产卵的雌性)以确定其生化组成。数字,volume,体重,还分析了来自转移和对照卵生雌性的卵的生化组成,作为其质量指标。女性生化成分不受温度的影响,因为对照和高温非产卵雌性有相似的脂质,蛋白质,和糖原含量。然而,卵巢成熟和产卵在33℃时受到抑制,这表明该温度对营养转移到卵母细胞的负面影响。将雌性移至28°C后,这种效果迅速逆转;来自对照和转移的产卵雌性的卵质量相似,除了后者的蛋白质含量较低。本结果为在热应力下进行繁殖的储备分配提供了有价值的信息。
Maternal provisioning is particularly important in invertebrates with abbreviated development because large energy reserves must be provided for the developing embryo. In this context, the objective of the present study was to analyze in an aquatic invertebrate with direct development the effect of temperature on female biochemical composition and reserve allocation to maturing ovaries, which determine egg quality. A decapod crustacean, the freshwater shrimp Neocaridina davidi, was used as experimental model. Newly hatched juveniles were exposed to 28 °C or 33 °C. Females showed mature ovaries and spawned at 28 °C (control ovigerous females), but no ovigerous female was found at 33 °C. After a 200-day period, half of the females at 33 °C were transferred to 28 °C, where they rapidly showed mature ovaries and spawned (transferred ovigerous females). Ovigerous females and females that did not spawn at 28 °C (control non-ovigerous females) and at 33 °C (high-temperature non-ovigerous females) were sacrificed to determine their biochemical composition. The number, volume, weight, and biochemical composition of the eggs from transferred and control ovigerous females were also analyzed as indicators of their quality. Female biochemical composition was not influenced by temperature, because control and high-temperature non-ovigerous females had similar lipid, protein, and glycogen contents. However, ovarian maturation and spawning were inhibited at 33 °C, which indicates a negative effect of this temperature on nutrient transfer to the oocytes. This effect was rapidly reversed after females were moved to 28 °C; the eggs from control and transferred ovigerous females were of similar quality, except for a lower protein content in the latter. The present results provide valuable information on reserve allocation to reproduction under thermal stress.