This study assessed the effects of different protein levels on the development of the mandibular gland (MG) in six-day-old worker bees (Apis mellifera) during the dearth period. Twenty colonies were randomly assigned to one of four experimental diets containing 0%, 23%, 25%, or 27% crude protein (CP), with five replicates each. The experimental diets were composed of feed meal and honey sirup. Each colony was provided with 30 g of formulated feed every 3 days over a 36-day period. At the end of the experimental period, ten six-day-old worker bees were collected from each treatment for the morphological analysis of their MGs. The area of the MG was significantly larger in the bees fed protein-enriched feeds than in the controls. The height of the secretory cells in the MG was also significantly greater in all colonies fed protein-enriched feed than in the control group. However, the group that received the feed with 23% CP had significantly taller secretory cells than the other groups. Based on regression analysis, the ideal level of protein in the diet for the development of the MG was 22.2% CP. Thus, the use of protein-enriched feed promotes greater increases in the area and height of secretory MG cells in six-day-old honey bee workers.

中文翻译：

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蛋白质饲料刺激蜜蜂（Apis mellifera）下颌腺的发育

本研究评估了不同蛋白质水平对六天大工蜂（Apis mellifera）在匮乏期下颌腺（MG）发育的影响。20 个菌落被随机分配到含有 0%、23%、25% 或 27% 粗蛋白 (CP) 的四种实验饮食中的一种，每个实验 5 个重复。实验日粮由饲料粉和蜂蜜糖浆组成。在 36 天的时间内，每 3 天向每个菌落提供 30 克配方饲料。在实验结束时，从每个处理中收集 10 只 6 日龄工蜂，对其 MG 进行形态学分析。在喂食富含蛋白质的饲料的蜜蜂中，MG 的面积明显大于对照组。在饲喂富含蛋白质的饲料的所有菌落中，MG 中分泌细胞的高度也显着高于对照组。然而，接受 23% CP 饲料的组的分泌细胞明显高于其他组。基于回归分析，饮食中用于发展 MG 的理想蛋白质水平是 22.2% CP。因此，使用富含蛋白质的饲料可促进六天大蜜蜂工蜂的分泌型 MG 细胞面积和高度的更大增加。