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Heat stress is one of the most challenging environmental stresses for broilers. Nowadays, it is becoming more prominent since the temperature around the world is increasing, due to climate change. This results in more and longer heat waves with higher temperature maxima. Farmers must find solutions for these severe heat exposures to avoid economic losses and to maintain the welfare of the broilers. Increased heat tolerance seems to be a promising solution. This systematic review investigates the effect of heat thermal manipulation (TM) during incubation on the post-hatch life of TM broilers compared to non-treated broilers, in standard conditions and under chronic/acute heat stress. Therefore, keywords regarding oxidative stress, thyroid gland, and production factors are searched to form a Boolean expression. This expression is used in the advanced search from Web of Science (WoS) to collect relevant papers. Then, some filtering techniques in WoS are applied together with exclusion criteria in the program StArt, to eliminate the irrelevant papers. From the remaining papers, the data is extracted according to a premade template in Excel. Excel is also used to visualise and analyse the results. Finally, the program R is used for a statistical analysis via a chi-squared test and the calculation of the standardised residuals. The results showed that the thermal tolerance of broilers can be increased via TM during incubation. This increased thermal tolerance is reached via a decrease in T3 levels, which leads to a lower body temperature and results in less stress/corticosterone levels, when exposed to heat stress. Eventually this results in lower mortality and an increased body weight of heat stressed TM broilers, compared to non-treated broilers. All of this can be achieved without negatively affecting these parameters under standard conditions. This means that in regions where broilers experience heat stress, TM during incubation can increase the profits of the farmer and increase the welfare of the broilers. However, it is important to apply the correct TM parameters during incubation. These are estimated at 38.5-39.0°C around embryotic days 7-18 for a duration between 9-18 hours/day.

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Om allerlei chronische niet-overdraagbare aandoeningen zoals cardiovasculaire ziektes, diabetes, overgewicht en kanker te voorkomen heeft de mens nood aan een bepaalde hoeveelheid fysieke activiteit. Al sinds het ontstaan van de mensheid werd voldoende fysieke activiteit gehaald uit dagelijkse bezigheden, zij het in de oudheid door jagen en eten verzamelen, of in modernere tijden door fysieke inspanningen op het werk of door het uitvoeren van huishoudelijke taken. De fysieke inspanning tijdens vele van deze dagelijkse bezigheden is in de hedendaagse samenleving echter sterk afgenomen door de automatisering van zowel de werk- als de privéomgeving. Ondanks de vele voordelen van deze automatisering ondervindt de globale bevolking dan ook één groot nadeel: het gebrek aan fysieke activiteit en de daarmee verbonden risico’s voor de menselijke gezondheid. Dit eindwerk kadert dan ook in het doel naar het vinden voor een alternatief om voldoende fysiek actief te zijn. Concreter worden de volgende twee onderzoeksvragen opgesteld: Ten eerste wat is de hartslagrespons tijdens het sportvissen op activiteiten die typisch zijn voor het vissen met een vaste hengel en een werphengel onder gecontroleerde omstandigheden? Ten tweede wat is de hartslagrespons tijdens het sportvissen op activiteiten die typisch zijn voor het vissen met een vaste hengel in de praktijk? In een eerste experiment werd de fysieke activiteit op basis van hartslag en 3D acceleratie geschat tijdens het simuleren van hengelen met een vaste hengel en het simuleren van actief hengelen met een werphengel en kunstaas op roofvis. Ter vergelijking werden hartslag en 3D acceleratie ook gemeten tijdens rustperiodes en wanneer er gewandeld werd. Uit de resultaten bleek dat voor het simuleren van hengelen met de vaste hengel de hartslag wel hoger lag ten opzichte van de rustperiodes, maar dat deze gemiddeld gezien 20.00% (75 BPM ten opzichte van 90 BPM) onder de hartslag tijdens het wandelen bleef. Enkel tijdens het simuleren van hengelen met de werphengel steeg de hartslag significant in vergelijking met deze tijdens het wandelen (respectievelijk 90 BPM en 94 BPM, of dus een stijging van 4.44%). Het actief hengelen met een werphengel lijkt dan ook een inspanning te zijn met voldoende fysieke activiteit. In een tweede experiment werd er effectief gevist langs de waterkant. Er werd geopteerd om enkel met de vaste hengel te vissen en dit op stromend water aangezien dat het meest voorkomende type hengelen is in Vlaanderen. Opnieuw werden hartslag en 3D acceleratie gemeten tijdens het experiment om nadien te kunnen vergelijken met rust. Opvallend was dat dit maal de hartslag gemiddeld gezien lager lag tijdens het hengelen dan tijdens de rustperiodes, namelijk 2.94% in vergelijking met de hartslag tijdens het zitten en 14.71% met die tijdens het staan. Hier kon dus uit afgeleid worden dat het hengelen met een vaste hengel eerder een relaxerende en dus anti-stresserende werking heeft, maar dus geen oplossing biedt voor het probleem van de fysieke inactiviteit. De fysieke activiteit tijdens het recreatief sportvissen is dus sterk afhankelijk van het type hengelen waarvoor geopteerd wordt. Actievere vormen zoals het hengelen met de werphengel met kunstaas op roofvis bieden een goed alternatief om het probleem van de fysieke inactiviteit aan te pakken, rustigere vormen zoals het hengelen met de vaste hengel echter niet. Belangrijk is wel om in het achterhoofd te houden dat het niet zo is

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The demand for pork continues to increase worldwide, making it crucial to ensure that pig production is sustainable while maintaining high standards of animal welfare and health. Our motivation behind this task was to optimize the pose estimation model for practical deployment in farm settings. This dissertation aims to develop a lightweight and accurate key point detection model for pigs on a farm, based on HRnet, a high-resolution network that preserves spatial accuracy throughout the process. To achieve the objective, we first review the latest methods for pig pose estimation and compare two paradigms for key point detection: top-down and bottom-up. We then describe the dataset of pig pictures that covers various environments and poses, and the annotation protocol that follows COCO annotator. We also introduce several metrics to evaluate the performance of key point detection algorithms, such as PCK, AUC, and EPE. Next, we report the experiments and results of applying HRnet to our dataset, and analyse the effects of different hyperparameters, such as batch sizes and input image size. We find that HRnet can achieve fast and accurate detection of 10 key points for pigs even with low-resolution images of [64,32] pixels, which enables efficient and ethical livestock farming. Finally, we conclude with some future work suggestions and contributions to the field of animal behaviour analysis.

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In recent years, the genetic selection of the meat-type broiler chicken resulted in a fast-growing animal. Apart from the fast body and muscle growth, an undesirable alteration to the chicken' thermoregulatory system have made these animals vulnerable for heat stress, especially in warm regions. Pre-hatch thermal conditioning or manipulation has become a major topic to prevent heat stress by altering the thermotolerance and thermosensation of the developing embryo. More knowledge is needed on how to assess these modifications due to the changes in thermal regime, in a non-invasive way. In this thesis, both frequency- and time-domain analysis were used to characterise the measured thermal respons of the chicken using sensors, expressed in both eggshell temperature and heat flux. Using the Short-Time Fourier Transformation (STFT), the spectral content of the whole incubation period was explored in a time-frequency distribution (TFD), i.e. the spectrogram. This frequency representation of the signal yielded new insights about some rhythmic components linked with embryonic development. However, the fixed time-frequency resolution of the STFT lacked performance in and around the transient parts of the signal, e.g. the temperature step inputs of the thermal treatment. Therefore, three different methods were proposed to visualise and quantify these step inputs in both time and frequency. Continuous Wavelet Transformation (CWT) in the form of a scalogram was proposed as good alternative for the spectrograms. These multi-resolution TFDs reveiled a new frequency component in between the temperature step which increased in frequency and magnitude each consecutive day of treatment. This component seemed to associate with the embryo' respons during the step input in temperature. In order to justify and quantify this assumption, wavelet decomposition was proposed as a quantitative tool to discriminate these treatments days. Apart from a clear difference between the first and last days in terms of energy, the visualisation of the detailed coefficient values suggest a more coordinated respons during the temperature steps in the last three days of incubation. Next, SISO Continuous-Time Transfer Function modelling was performed for both temperature and heatflux. The developing embryo' transient response is represented by a (mechanical) characteristic equation of the estimated transfer function, of which the eggshell temperature and heatflux were proven to be the step- and impulse respons of the respective system. Finally, the natural frequency and damping coefficient were linked to the frequency results, indicating a shift in the thermoregulatory system from proximate non-adaptive to a proximate adaptive mechanism in the last phase of incubation. It was concluded that simply placing a surrounding temperature sensor is enough to capture the rhythmic expressions from the developing embryo.

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Previous studies have shown microwell arrays can be used in conducting digital bioassays. In the digital ELISAs (dELISAs) explored in this thesis, single molecules are captured on magnetic beads, labelled with an enzyme, and confined in individual microwells with a fluorogenic substrate. As the resulting fluorescent signal is confined to a small volume of solution, local concentrations are high enough to produce a detectable signal. An efficient way to confine the contents of each well is by using hydrophilic in hydrophobic (HIH) microwell arrays. This thesis builds on previous work in order to innovate the fabrication of microfluidic chips with HIH microwell arrays for ultrasensitive detection of biomarkers using a reaction injection molding (RIM) process on the mOSTE polymer. The RIM process was chosen for its scalability, for many other microwell fabrication techniques thus far had relied on technologies more difficult to scale to commercial environments. This thesis further optimized the RIM procedure for mOSTE into a process that was more durable, robust, and produced chips with fewer quality defects. A mOSTE casting procedure was developed as one that was more amenable to laboratory environments, and this was compared with RIM in terms of ease-of-use and the quality of the chips produced. Surface energy characterization experiments of the chips led to increased mold incubation time before curing and the development of a more precise predictive model to describe the effect of incubation. This served to better facilitate droplet movement, a key factor in executing a dELISA. Finally, using chips generated with the improved fabrication procedures, the potential of performing digital bioassays in the microwells was assessed by examining the ability to seal aqueous reagents and seed magnetic beads, key steps of the dELISA. A seeding efficiency of 97% was obtained, indicating a high potential for this process. The model bioassay was then conducted as a proof-of-concept that the new microwell arrays were capable of enabling protein detection. Although further work is needed in order to have a more repeatable bioassay, this study demonstrates feasibility and shows the potential for RIM and mOSTE to produce HIH microwell arrays for bioassays.