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During motor preparation, the attention is paid more and more frequently to the complex significance of fatigue in the case of the achieved sport outcome. The complexity of this process has not been utterly explained so far. It is important to acquire the profound knowledge about the central and peripheral fatigue while explaining this mechanism, because they remain in the background of the human body malfunction. It needs to be emphasized that both fatigue mechanisms should not be analyzed separately, because they are subordinated to one another. The changes mechanism in central nervous system (CNS) influenced by physical exertion leads to reticular formation impairment. This in turn results in analytic and decision making process malfunction. The proper functioning of these centers depends on appropriate neurotransmitters concentration. The short tryptophan to serotonin metabolic pathway plays a significant role in the central fatigue development. The concentration increase of this hormone leads to CNS malfunction, which causes the above mentioned changes. The purpose of this paper was to show, based on the current literature data, the predisposing mechanisms and factors in the development of fatigue.
Carbon dioxide is commonly used to anesthetize the bee queen during instrumental insemination. It can be used both during the insemination procedure, and also to speed up the start of oviposition of instrumentally inseminated queen bees. Anesthesia is not indifferent to the bees’ condition and is unable to reduce the queen latency period to a similar duration as in naturally mated queens. Aside from experiments on bee queens research on worker bees is also conducted because of costs reduction as well as the fact that adverse effects of anesthesia are more pronounced in worker bees than in queens. Therefore the aim of this study carried out on worker bees is to determine the influence of different atmospheric compositions during their awakening from anesthesia. The study was conducted in 2008 in the apiary of the Apiculture Division of the Warsaw University of Life Sciences – SGGW. 3960 Carniolan bees at the age of 2 weeks were studied. All of the 10 bees placed in plastic mail cages were anaesthetized with carbon dioxide for 3 minutes and then awakened in a chamber with a controlled composition of the atmosphere. 33 repetitions were conducted, each of them included 6 groups of the following atmospheric compositions: 1. oxygen 100%; 2. nitrogen 100%; 3. oxygen/nitrogen 30%/70%; 4. oxygen/nitrogen 50%/50%; 5. oxygen/nitrogen 70%/30%; 6. control group, natural composition of atmospheric air. Awakening time was determined by first breathing movements observed and then upon their fully awakening. The awakening of bees after carbon dioxide anesthesia follows a different course in relation to the atmospheric composition during recovery. Awakening in a pure oxygen and pure nitrogen atmosphere significantly prolongs the time to the appearance of the first respiratory movements and the total time to full awakening of bees (in comparison to the control group). Awakening in an atmosphere composed of 70% of oxygen and 30% of nitrogen significantly reduces the time to the appearance of the first respiratory movements and the time of the full awakening of bees. The highest survival rate 14 days after awaking was found in group 5 (70% of oxygen and 30% of nitrogen). The shortest survival rate, (22 days), had bees that awakened in a pure nitrogen atmosphere.
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