The complex agonistic repertoire between male lobster cockroaches (Nauphoeta cinerea) makes this species an excellent model for aggression studies. During the establishment of dominance hierarchies, 3-hydroxy-2-butanone (3H-2B) functions as a suppression pheromone, keeping the rivals in a submissive state. In the present study, we evaluated the release of 3H-2B by dominant individuals across four different time phases within the 24-h photoperiod, i.e., early scotophase (ES), late scotophase (LS), early photophase (EP), and late photophase (LP). For each time phase, we collected volatile pheromones during a 60-min first-encounter fight to measure the level of released 3H-2B. Subsequently, the amount of 3H-2B remaining in the sternal glands of dominant and subordinate individuals was measured and compared to socially naïve male controls. Release of 3H-2B was relatively high during ES or LP first-encounter fights, compared to LS or EP encounters. The attack duration and aggressive posture intensity in dominant males were positively correlated with the amount of 3H-2B release in all four phases. A similar statistical distribution was found between the amount of 3H-2B released by dominant males and the amount of 3H-2B in the sternal glands of naïve male sternal during LS, EP, and LP. However, during ES, the statistical distribution of 3H-2B released by the dominant was significantly greater than the distribution of 3H-2B content in socially naïve male sternal glands. The observed phase-dependence of 3H-2B release might be due to variations in 3H-2B biosynthesis or the scotophase-specific behavior of naïve males, wherein an aggressive posture is spontaneously adopted with concomitant 3H-2B release.

中文翻译：

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光周期依赖性释放雄性龙虾蟑螂Nauphoeta cinerea中的抑制信息素

雄性龙虾蟑螂（Nauphoeta cinerea）之间的复杂激动性库）使该物种成为侵略研究的绝佳模型。在建立优势等级的过程中，3-羟基-2-丁酮（3H-2B）起到抑制信息素的作用，使竞争对手处于顺从状态。在本研究中，我们评估了显性个体在24小时光周期内四个不同时间段内的3H-2B释放，即早期暗期（ES），晚期暗期（LS），早期暗相（EP）和晚期光相（LP）。对于每个时间阶段，我们在60分钟的首次战斗中收集了挥发性信息素，以测量释放的3H-2B的水平。随后，测量了优势个体和从属个体的胸骨腺中残留的3H-2B量，并将其与天真的男性对照进行比较。在ES或LP的首次遭遇战中3H-2B的释放量相对较高，相较于LS或EP遭遇。在所有四个阶段中，优势男性的攻击持续时间和攻击性姿势强度与3H-2B释放量呈正相关。在LS，EP和LP期间，优势男性释放的3H-2B量与幼稚男性胸骨的胸腺中3H-2B的量之间发现了类似的统计分布。然而，在ES期间，显性男性释放的3H-2B的统计分布显着大于未婚男性胸骨中3H-2B含量的分布。观察到的3H-2B释放的相依性可能是由于3H-2B生物合成的变化或幼稚雄性的phase相特异性行为引起的，其中伴随3H-2B释放自发地采取攻击性姿势。在所有四个阶段中，优势男性的攻击持续时间和攻击性姿势强度与3H-2B释放量呈正相关。在LS，EP和LP期间，优势男性释放的3H-2B量与幼稚男性胸骨的胸腺中3H-2B的量之间发现了类似的统计分布。然而，在ES期间，显性男性释放的3H-2B的统计分布显着大于未婚男性胸骨中3H-2B含量的分布。观察到的3H-2B释放的相依性可能是由于3H-2B生物合成的变化或幼稚雄性的phase相特异性行为引起的，其中伴随3H-2B释放自发地采取攻击性姿势。在所有四个阶段中，优势男性的攻击持续时间和攻击性姿势强度与3H-2B释放量呈正相关。在LS，EP和LP期间，优势男性释放的3H-2B量与幼稚男性胸骨的胸腺中3H-2B的量之间发现了类似的统计分布。然而，在ES期间，显性男性释放的3H-2B的统计分布显着大于未婚男性胸骨中3H-2B含量的分布。观察到的3H-2B释放的相依性可能是由于3H-2B生物合成的变化或幼稚雄性的phase相特异性行为引起的，其中伴随3H-2B释放自发地采取攻击性姿势。