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Serotonin modulates various physiological processes and behaviors. This study investigates the role of 5-HT in locomotion and feeding behaviors as well as in modulation of sensory-motor circuits. The 5-HT biosynthesis was dysregulated by feeding Drosophila larvae 5-HT, a 5-HT precursor, or an inhibitor of tryptophan hydroxylase during early stages of development. The effects of feeding fluoxetine, a selective serotonin reuptake inhibitor, during early second instars were also examined. 5-HT receptor subtypes were manipulated using RNA interference mediated knockdown and 5-HT receptor insertional mutations. Moreover, synaptic transmission at 5-HT neurons was blocked or enhanced in both larvae and adult flies. The results demonstrate that disruption of components within the 5-HT system significantly impairs locomotion and feeding behaviors in larvae. Acute activation of 5-HT neurons disrupts normal locomotion activity in adult flies. To determine which 5-HT receptor subtype modulates the evoked sensory-motor activity, pharmacological agents were used. In addition, the activity of 5-HT neurons was enhanced by expressing and activating TrpA1 channels or channelrhodopsin-2 while recording the evoked excitatory postsynaptic potentials (EPSPs) in muscle fibers. 5-HT2 receptor activation mediates a modulatory role in a sensory-motor circuit, and the activation of 5-HT neurons can suppress the neural circuit activity, while fluoxetine can significantly decrease the sensory-motor activity. [ABSTRACT FROM AUTHOR]

Objective: Internal body temperature is an essential parameter in evaluation an animal's general health status. The rectal temperature as 'gold standard' requires restraining of the animal which may cause stress especially when not accustomed to handling procedures. Stress on the other hand should whenever possible be avoided as it negatively affects animal welfare and may increase body temperature. The present study evaluated whether measuring the body surface temperature with an infrared thermometer (IRT) may represent a stressless alternative method to rectal body temperature measurements., Material and Methods: Twelve male fattening pigs were included in the study. Body temperature was measured once a week for 11 weeks. Body surface temperature measurements were performed in the areas of the forehead, caudal base of the ear and anus using two infrared thermometers (IRT1 and IRT2) each., Results: Throughout the study, all pigs were clinically healthy. Best repeatability was found for the rectal thermometer and IRT1 in the anus region. Homogeneity of variance was not found for the measurements of the three thermometers. Mean values of body temperature were significantly different (p<0,05) between thermometers and measurement points. Thereby, the type of thermometer and measurement point possessed a moderate to strong effect. The Bland-Altman plot shows that differences in the values of the thermometers and measurement points are within the acceptable range of variation (95% interval). However, the range of variation is too substantial for clinical assessment of the body temperature., Conclusion: The repeatability of temperature data measured with IRT on the body surface of pigs is acceptable. For this procedure, restraining the animals is not necessary, therefore reducing the animal's stress level during the clinical examination. However, the correlation to the rectal body temperature is weak to moderate., Clinical Relevance: In order to use IRT for health monitoring in animals, reference values for respective IRT and measurement points need to be established. In the current study no case of hyper- or hypothermia occurred. Further research is warrented to evaluate whether IRT reliably detect fever., Competing Interests: Die Autoren erklären, dass kein Interessenkonflikt besteht., (The Author(s). This is an open access article published by Thieme under the terms of the Creative Commons Attribution-NonDerivative-NonCommercial-License, permitting copying and reproduction so long as the original work is given appropriate credit. Contents may not be used for commercial purposes, or adapted, remixed, transformed or built upon. (https://creativecommons.org/licenses/by-nc-nd/4.0/).)

Following the accidental feeding of a compound feed containing the coccidiostat nicarbacin in layer breeder flocks (Lohmann Brown Classic), the birds displayed distinct clinical signs within a few hours. Mortality increased during the following 5 days, whereas laying performance and hatching rate of eggs during this period decreased markedly. Egg shell discoloration was observed as early as during the first day. As a consequence, an association between feeding of the coccidiostat nicarbacin and the observed symptoms was assumed. Recent studies indicate that Nicarbacin reduces the activity of aminolevulinic acid synthase type 1 (ALAS 1), which is responsible for the synthesis of protoporphyrin IX in the shell gland as main compound of brown egg shells. Reduced laying performance and increased mortality was likely due to nicarbacin-induced deregulated body temperature homeostasis and concomitant imbalances in acid-base status of the animals. The case reveals that the accidental feeding of nicarbacin to non-target animals such as laying hens and their parents may result in acute clinical symptoms. This highlights the necessity of appropriate care in handling feed additives and their premixes for specific non-target animals and should sensitize farmers and veterinarians., Competing Interests: Die Autoren erklären, dass kein Interessenkonflikt besteht., (Thieme. All rights reserved.)