Virtanen Miiro Ilmari, Brinchmann Monica Fengsrud, Patel Deepti Manjari, Iversen Martin Haugmo
Faculty of Biosciences and Aquaculture, Nord University, Bodø, Nordland, Norway.
Front Physiol. 2023 Apr 3;14:1147235. doi: 10.3389/fphys.2023.1147235. eCollection 2023.
The desire to understand fish welfare better has led to the development of live monitoring sensor tags embedded within individuals for long periods. Improving and understanding welfare must not come at the cost of impaired welfare due to a tag's presence and implantation process. When welfare is compromised, the individual will experience negative emotions such as fear, pain, and distress, impacting the stress response. In this study, Atlantic salmon () underwent surgical implantation of a dummy tag. Additionally, half of this group was introduced to daily crowding stress. Both groups and an untagged group were followed for 8 weeks using triplicate tanks per group. Sampling took place once a week, and where stress was given, it was conducted 24 h before sampling. Stress-related measurements were taken to understand if tagging caused chronic stress and explore the chronic stress response and its impact on wound healing. Primary stress response hormones measured included CRH, dopamine, adrenocorticotropic hormone, and cortisol. Secondary stress response parameters measured included glucose, lactate, magnesium, calcium, chloride, and osmolality. Tertiary stress response parameters measured included weight, length, and five fins for fin erosion. Wound healing was calculated by taking the incision length and width, the inflammation length and width, and the inside wound length and width. The wound healing process showed that stressed fish have a larger and longer-lasting inflammation period and a slower wound healing process, as seen from the inside wound. The tagging of Atlantic salmon did not cause chronic stress. In contrast, daily stress led to an allostatic overload type two response. ACTH was elevated in the plasma after 4 weeks, and cortisol followed elevation after 6 weeks, highlighting a breakdown of the stress regulation. Fin erosion was elevated alongside cortisol increase in the stressed group. This data suggests that tagging previously unstressed fish in a controlled environment does not negatively affect welfare regarding stress responses. It also indicates that stress delays wound healing and increases the inflammatory response, highlighting how continued stress causes a breakdown in some stress responses. Ultimately, the tagging of Atlantic salmon can be successful under certain conditions where proper healing is observed, tag retention is high, and chronic stress is not present, which could allow for the possible measurement of welfare indicators smart-tags.
人们希望更好地了解鱼类福利，这促使了可长期嵌入鱼体的活体监测传感器标签的发展。改善和了解福利绝不能以标签的存在和植入过程导致福利受损为代价。当福利受到损害时，鱼体会经历恐惧、疼痛和痛苦等负面情绪，从而影响应激反应。在本研究中，大西洋鲑（）接受了假标签的手术植入。此外，该组中有一半的鱼每天还会遭受拥挤应激。两组鱼和一组未标记的鱼每组使用三个重复水箱进行了8周的跟踪观察。每周进行一次采样，在施加应激的情况下，在采样前24小时进行。通过测量与应激相关的指标，以了解标记是否会导致慢性应激，并探究慢性应激反应及其对伤口愈合的影响。测量的主要应激反应激素包括促肾上腺皮质激素释放激素（CRH）、多巴胺、促肾上腺皮质激素（ACTH）和皮质醇。测量的次要应激反应参数包括葡萄糖、乳酸、镁、钙、氯和渗透压。测量的第三级应激反应参数包括体重、体长和五个鳍的鳍侵蚀情况。通过测量切口长度和宽度、炎症长度和宽度以及伤口内部长度和宽度来计算伤口愈合情况。伤口愈合过程表明，从伤口内部情况来看，遭受应激的鱼炎症期更大且持续时间更长，伤口愈合过程更慢。大西洋鲑的标记并未导致慢性应激。相比之下，每日应激导致了二级非稳态过载反应。4周后血浆中促肾上腺皮质激素（ACTH）升高，6周后皮质醇随之升高，这突出了应激调节的崩溃。在遭受应激的组中，鳍侵蚀随着皮质醇的增加而加剧。这些数据表明，在受控环境中标记先前未受应激的鱼不会对应激反应方面的福利产生负面影响。这也表明应激会延迟伤口愈合并增加炎症反应，突出了持续应激如何导致某些应激反应的崩溃。最终，在观察到适当愈合、标签保留率高且不存在慢性应激的某些条件下，大西洋鲑的标记可以成功进行，这可能允许通过智能标签测量福利指标。
