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This study was conducted to address the problem of root-knot nematodes (Meloidogyne spp.) affecting semi-temperate vegetables cultivated by small-holder farmers in the highlands (Cordillera) in the northern part of Luzon, Philippines. Our general objective was to assist in the development of root-knot nematode management strategies suitable for small-holding farming that could result in improved crop productivity and quality. There are four experiments included in our study which started from the survey of plant-parasitic nematodes in the principal agricultural farms in Benguet Province. The objectives of this part of our study were to update the incidence of plant-parasitic nematodes associated with semi-temperate vegetables in Benguet Province and to identify the predominant plant-parasitic nematode species associated with semi-temperate vegetables in this province which is the major semi-temperate vegetables producing region of the Philippines. The sampling was carried out between the dry seasons of 2004 and 2005 (December 2004 to March 2005). This was followed by a sampling during the rainy season of 2005 (June-July). The last sampling was carried out during the dry season of 2006 (February-May). The results of this survey showed that thirteen genera (Aphelenchoides, Criconemella, Ditylenchus, Globodera, Helicotylenchus, Hoplolaimus, Meloidogyne, Longidorus, Paratrichodorus, Pratylenchus, Trichodorus, Tylenchus, and Xiphinema) of plant-parasitic nematodes were found associated with various semi-temperate vegetable crops in Benguet Province. Among these taxa, Helicotylenchus, Meloidogyne and Pratylenchus were the most predominant. Four nematode genera which contain species that can vector plant viruses were also found in the rhizosphere of several semi-temperate vegetables during the survey: Trichodorus, Paratrichodorus, Longidorus and Xiphinema. To our knowledge, this is the first report of the presence of Paratrichodorus, Longidorus and Xiphinema (americanum) on semi-temperate vegetables in the Philippines.From the above mentioned experiment, the predominant plant-parasitic nematode Meloidogyne incognita was singled out for further experimentation in the greenhouse. The objective of this part of our study was to evaluate the host response (susceptibility and sensitivity) of six semi-temperate vegetables commonly grown today in the highlands of Benguet Province to M. incognita. Six semi-temperate vegetables (carrot, celery, cucumber, lettuce, tomato and sweet pepper) were evaluated for their host response to infection by M. incognita. The host response index showed that no sources of resistance were found against M. incognita in the carrot cultivars which were evaluated. The cultivars, Caroline, Chunhong andLucky Kuroda were classified as intermediate, the cultivars Argo Super Kuroda and Royal Chantenay were classified as moderately susceptible, and the cultivarsNew Kuroda, New Kurodagosun and Victoria were classified as susceptible to infection by M. incognita.The two celery cultivars that were evaluated, Tall Utah Supreme and Utah 52-70 R Imp, showed some resistance to infection by M. incognita during the early assessment period. However, both cultivars became susceptible to this nematode species during the second assessment period. Nevertheless, since both cultivars still provided marketable yields even with high nematode infection level they can be classified as tolerant to infection by M. incognita.Of the cucumber cultivars evaluated, Poinsett was classified as moderately susceptible to infection by M. incognita while the three other cultivars evaluated, Cyclone, Gen. Lee and Melissa, were classified as highly susceptible. However, because of the increase in yield even with a high nematode infection level in the latter two cultivars, it was concluded that they are tolerant to infection by M. incognita.Sources of resistance to M. incognita were found in the lettuce cultivars evaluated: Great Lakes and Grand Rapids were classified as immune and resistant, respectively. Tolerance was also found in Red Wave. The cultivars Attrazione and Tyrol were classified as moderately susceptible while Ballon and Red Salad Bowl were classified as susceptible and highly susceptible, respectively, to infection by M. incognita. Except for cvs Great Lakes and Grand Rapids, all the other lettuce cultivars which are of loose-leaf type such as Ballon, Apache, Lollo Rosa, Red Salad Bowl, Tyrol, Xanadu etc. can be harvested in less than 8 weeks after transplanting. If these plants were germinated in sterile soil in seedling trays and harvested earlier in the field, the root-knot nematodes would not be able to complete their life cycle in the host during the cropping period. Hence, the plants can avoid further damage through secondary infection by the nematodes. It would also lessen the population of the root-knot nematodes in the soil even for those susceptible plants.The commercial tomato cultivar Apollo and five breeding lines were classified as highly susceptible to M. incognita while the two newly introduced commercial cultivars Marmande 1 and Marmande 2 were classified as susceptible to this nematode species. Cultivar Red Cherry was considered as a more tolerant cultivar due to its ability to produce marketable yields in spite of a high nematode infection level. The sweet pepper cultivar California Wonder was classified as moderately susceptible to M. incognita infection while Smooth Cayene and Yolo Wonder were classified as susceptible and highly susceptible, respectively.A crop rotation scheme was designed to examine the host status for a local M. incognita population of the most commonly cultivated cash crops in the Cordillera Administrative Region (CAR) usually grown in rotation with carrot. Crops which were considered effective in suppressing root-knot nematode populations, such as marigold (Tagetes erecta), but are considered of no economic value in small-holding farming were not included in our study. A greenhouse experiment was conducted at Benguet State University, La Trinidad, Benguet, Philippines, during a 2-year-period (2006-2007). The rotation crops were planted during the 2nd and the 3rd cropping period while carrot was planted during the 1st and the 4th cropping periods. The cropping sequence was as follows: (i) carrot during the dry season of 2006 (= 1st cropping period), (ii) rotation crops during the dry season of early 2007 (= 2nd cropping period), (iii) rotation crops during the wet season of 2007 (= 3rd cropping period), (iv) carrot during the dry season of late 2007 (= 4th cropping period). The use of onion, strawberry, broccoli and sweet corn as rotation crops suppressed the multiplication of M. incognita. However, resurgence of the population was observed when susceptible crops were planted subsequently. A yield increase was noted in all crops except in crops which supported less nematode population densities such as onion, broccoli and sweet corn. These crops, somehow, did not give the expected yield increase. Given this situation, it would be helpful if other nematode management practices could be applied before planting susceptible crops. Nevertheless, the information obtained during our study is still useful to growers in Benguet Province since these two crops are being used already by local farmers in the highlands.Several forms of management for M. incognita have been reported in most agricultural crops. One promising practice is using silicon amendment to alleviate damage caused generally by fungi or bacteria. Until now, little had been studied for root-knot nematodes, therefore, the objectives of this part of our study were to: (1) investigate the effects of silicon on root-knot nematode, M. incognita; and (2) determine its consequent effects on plant growth and yield of carrot, celery, tomato and cucumber. This part of our study comprised of two experiments which were conducted in the greenhouse. In the first experiment, seeds of celery and tomato were sown in polyethylene seedling trays (2.54 cm-diameter) prior to transplanting in bigger plastic pots (18 cm-diameter) containing ±2.5 kg of sterilized soil. Celery seeds were germinated and grown for 8 weeks while tomato was grown for 4 weeks. On the other hand, seeds of carrot and cucumber were directly transplanted in pots. In the first experiment, silicon was applied in the form of sodium metasilicate in different concentrations (0, 10, 20, 40 and 80 mg/l) and a commercial fertilizer Duofus. In the second experiment, silicon in the form of sodium metasilicate was applied in cucumber in concentrations; 0, 20 and 40 mg/l, which were applied either once or weekly during its cropping period, and which were applied on the leaves and roots alone or applied to both plant parts. The benefits of Si in M. incognita reduction and alleviating damage by the nematode specifically in cucumber plants have been shown partially in our study. These effects however are not true for all the plants tested like carrot, celery and tomato. Slight nematode reduction was observed from the latter plants in some concentrations but yield was not generally increased. This was likely because cucumber plants are said to be intermediate accumulator of Si and thus, can benefit more from the effect of Si amendment. Nevertheless, we can conclude that supplemental Si can contribute to M. incognita reduction and enhance better yield particularly in cucumber even from infected plants, and hence, should warrant further investigation.

Academic collection --- Theses

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A variety of analytical methods is used in both, academia and industry for the analysis of food and beverage products. Standard wet chemistry based methods often suffer from a high instrument cost, laborious and time-consuming sample preparation and the need for skilled operators. Because of these problems with most instrumental techniques nowadays used for food analysis, there is a need for alternative methods and techniques that are fast, simple and reliable. Fourier Transform Infrared (FT-IR) spectrometry is an emerging technique in food science that potentially fulfills these requirements. FT-IR spectrometry is based on the absorption of IR light by the chemical components present in a sample. The IR spectrum is unique for every molecular structure and the intensity of absorption is directly related to the concentration of the absorbing species. FT-IR spectrometry is a very versatile method with respect to sample presentation and includes many different strategies appropriate in each particular application. The knowledge of the optimal FT-IR sample presentation method is important for the development of the methodology and its implementation in practical settings. The main objective of this thesis was to study the potential of different sample presentation strategies of FT-IR spectroscopy in food applications.In the first part of the thesis, two different FT-IR sampling techniques were studied in greater detail with respect to food analysis: the attenuated total reflection accessory (ATR) and a novel high-throughput screening module (HTS). In ATR, the evanescent IR wave is produced by transmitting the IR beam through a crystal of high refractive index. To obtain a signal the generated evanescent wave is brought into contact with a sample. In HTS the IR radiation is transmitted through the microplate with samples on top of it and allows for fast analysis of many samples in short time. The potential of both ATR and HTS strategies of FT-IR spectrometry was evaluated in two food systems – beer and milk. An advanced data analysis approach, which included empirical estimation of the best spectral preprocessing and variable selection method, was used for prediction of quality parameters and components of beer and milk samples based on their IR spectra. The results showed that both ATR/FT-IR and HTS/FT-IR can be used as a rapid analytical technique for the determination of major quality parameters and components in food samples, and therefore, has the potential to be implemented in real industrial settings. Even though the prediction results for HTS were found to be worse than for ATR, this method can still be useful for screening major components of large sample numbers of various food products. In the second part of the research, a microfluidic lab-on-a-chip platform was developed as a novel sample presentation strategy. It was specifically designed for compatibility with FT-IR microspectroscopic detection. FT-IR microscopy with a focal plane array (FPA) detector allowed to take chemical snapshots of the sample by acquiring thousands of IR spectra simultaneously, measured from a specific location of the sample. This provided not only spectral, but also spatially resolved information. First, as a proof-of-concept the microfluidic presentation method was used successfully for FT-IR chemical imaging of continuous and segmented flow in the microchannels. Second, a kinetic study of enzymatic reaction of D-glucose with glucose oxidase as a model system was carried out and compared to the ATR/FT-IR measurements. The obtained results showed that the integration of microfluidics and FT-IR microscopy could serve as an innovative bio(molecular) detection concept that can be applied for investigation of the kinetics of different biochemical reactions. It offers new opportunities in bioassays and microfluidics

Academic collection --- Theses

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Abstract Indiscriminate deforestation is endangering some regions all over the globe. Localities in tropical forests that feature exceptional concentrations of species with exceptional levels of endemism and that face exceptional degrees of threat are defined as hotspots (Myers, 1988). One of them is “Tropical Andes” and Ecuador is part of it. In highly deforested areas of the Ecuadorian lowland rain forests, Vriesea is one of the most representative genera among bromeliads. Therefore this genus, represented by Vriesea ‘Ginger’, was used as model plant in this study. In the future, Ecuadorian management of natural resources and conservation legislation have to be improved to avoid even more ecological damage. In the scope of creating tools to improve management and conservation of plant species, this PhD research focuses on possible spontaneous flowering induction “SFI” triggers in order to improve our understanding of this event. Flowering synchronization is utmost important for the continuity of a healthy gene pool for a species. Moreover, a better knowledge about the way a plant species controls flowering constitutes the core of any project that aims to preserve a plant species in his natural habitat.The experimental plant material is described and the time it takes the model plant to show anthesis is determined. Juvenile and mature stages are defined. Juvenility is left behind when plant reaches a fresh weight of 20 g (18 weeks of growth in the greenhouse). This is further confirmed by the analysis of ACC and MACC before and after the plant reaches that fresh weight. Based on the knowledge that bromeliads are flower induced by means of ethylene, treatments believed to spur its biosynthetic pathway were applied to Vriesea ‘Ginger’ plants.On the one hand, mechanical, geotropical and drought treatments applied to assess plants response did not yield any flower induction. However drought did induce “tubing”. “Tubing” is a kind of protection against drought of the apical meristem by the young leaves creating a tube of leaves at the center of the central tank of the plants and by this limiting water loss. “Tubed” plants did not become flower inducible using ethylene. On the other hand, light treatments induce Vriesea ‘Ginger’ plants prone to flower. This is achieved by first decreasing the irradiation light intensity followed by increasing irradiation light intensity. Plants exposed to 0.5 µmol m-2s-1 for four weeks (400 W high pressure sodium lamps) with subsequent increase to 15 or 30 µmol m-2s-1 (400 W high pressure sodium lamps) yielded flower induction of 165 g fresh weight or heavier plants. Higher flower induction was achieved by finalization with 30 µmol m-2s-1 thence suggesting the need of a specific Δ irradiation level to induce plants more efficiently. This was confirmed by the exposure to 100 µmol m-2s-1 (400 W high pressure sodium lamps) of the same plant material under the same initial conditions, showing no flower induction at all for plants up to 225 g fresh weight. High Δ irradiation level proved to have no or even an inhibiting effect on flower induction. Not only light intensity but also light quality definitely plays a role during flower induction. Whereas the 12h exposure of Vriesea ‘Ginger’ plants to one LED light source UV-A (350 nm) and NIR (920 nm) had no effect on flower induction, the exposure of the plants to: 660 nm (11.5 µmol m-2s-1), 630 nm (9.8 µmol m-2s-1), 530 nm (8.6 µmol m-2s-1) and 420 nm (9.7 µmol m-2s-1) made plants from 315 g and heavier prone to flower induction, resulting in at least 40% of the plants to bloom. None of the lighter plants, exposed to the same light intensity or less, were flower induced. The only exceptions were 30% of the plants of 145 and 225 g fw exposed to 5 µmol m-2s-1 (420 nm). 420 nm was the only LED light treatment able to induce 145 g plants, highlighting the importance of blue light during the flower inducive process. 530 nm (8.6 µmol m-2s-1) made 100% of the plants prone to flower induction. This proves against the traditional thought that green light has no major influence on plant physiology behavior.Exposure of plants to two LED-types sources for 12h a ratio ≈ 2:1 of 480 nm (12 µmol m-2s-1) and 630 nm (6.1 µmol m-2s-1) yielded in a flower induction of 40% (225 g plants) and 60% (145 g plants), therefore highlighting once again the importance of blue light. By changing the ratio ≈ 1:2 of 480 nm (6.1 µmol m-2s-1) and 630 nm (12.5 µmol m-2s-1) it was possible to obtain at least 40% of flower induction of 205 g or heavier plants. 660 nm (11.5 µmol m-2s-1) and 730 nm (3.2 µmol m-2s-1) induced 60% of 285 g plants. Irradiating 730 nm (3.2 µmol m-2s-1) for 1h after 12h of 660 nm (11.5 µmol m-2s-1) yielded 60% of induction (327 g plants) and 30% (205 g plants), suggesting that other photoreceptor other than phytochrome might play a role in Vriesea ‘Ginger’ flower induction. Almost with all light treatments it can be said that the higher the fresh weight of the plants, the higher the potential to flower. A total of two “SFIs” were witnessed and both origins were traced down to January: the first one being on 12/01/2009 ± 8 days and the second and last one on 21/01/2010 ± 8 days. Spectral analysis during December 2010-January 2011 showed subtle variation in the values of R:FR ratio (660:730 nm), R/B (660:450 nm) and B:FR (450:730 nm) compared with February, March and April 2011. This suggests that under natural conditions, far-red light (730 nm), blue light (450 nm) and low PAR irradiance might be important in creating flower inducive conditions, which is coherent with the other light experiments conducted. Furthermore, “SFI” is linked with clouding in the rainy seasons in nature as it increases the amount of blue light that reaches plants and at the same time decreases the light intensity plants are exposed to. Both being environmental cues that can trigger SFI under natural conditions.

Academic collection --- Theses

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Food quality is an important aspect for the food industry which refers to the production of safe, high nutritional as well as tasty food products. To meet consumer requirements food manufacturers would like to have fast, accurate and non-destructive quality control techniques. Visible (Vis) and Near Infrared (NIR) spectroscopy has been extensively applied as non-destructive quality inspection technique. Traditionally, the quality attributes are predicted based on statistical relations between the acquired spectra and the properties of interest, which are established through the use of multivariate calibration methods. Although these multivariate statistical methods have been extensively used for non-destructive prediction of quality attributes, in complex biological materials such as food these data-based models often prove not to be robust, due to the complex interaction of incident light with food involving both absorption and scattering of the light. Inability of conventional Vis/NIR spectroscopy to separate scattering and absorption information contained in the spectra limits its robustness for prediction of the chemical composition and its usefulness for determination of the microstructure of foods. To overcome the limitations of classical Vis/NIR spectroscopy this PhD research aimed to separate the information on the scattering and absorption properties of food samples by combining multiple diffuse reflectance measurements which are resolved in space. For this purpose, a setup for contactless spatially resolved spectroscopy (SRS) in the 500-960 nm range has been elaborated by combining a focused broadband light beam for the illumination with a hyperspectral line-scan camera for contactless acquisition of SRS profiles. To estimate the absorption coefficient and the reduced scattering coefficient from the SRS profiles acquired at every wavelength, an iterative estimation has been implemented around a data based light propagation model. This metamodel was trained and validated by means of liquid and solid phantoms covering a wide range of optical properties relevant for food products. The reference optical properties of these phantoms were calculated from double integrating spheres (DIS) measurements, the reference technique for bulk optical properties measurement on turbid samples. The forward and inverse validation of the metamodeling approach on the optical phantoms showed good prediction accuracy. This indicates that this combination of hyperspectral scatter imaging with an inverse light propagation model can provide a fast and accurate estimation of the bulk optical properties of turbid samples, such as foods. This technique was then used to estimate the bulk optical properties of different model foods: sugar foams with the same composition, but different microstructures induced by different foaming times, crispy breads produced with different extruder settings, and Braeburn apples stored for a longer period under controlled atmosphere (CA) conditions and exposed to shelf-life. The estimated optical properties were then used to evaluate the food quality attributes by relating them to the composition and microstructure for better understanding the structure-property relations. Finally, the estimated scattering properties of these food samples were correlated with destructive measurements: X-ray micro-CT (sugar foam), universal texture analyzer (crispy breads and Braeburn apples) for non-destructive estimation of the microstructure parameters of the aforementioned samples. Clear relations were observed between the estimated bulk optical properties (scattering property) and microstructure of the sugar foams and crispy bread samples. These results support the potential of hyperspectral scatter imaging to provide an indirect estimation of the food composition and texture parameters in a rapid and non-contact way. This makes it a very interesting technique for online quality inspection and process monitoring in the food industry. While good results were reported for the model foods, the results for apple fruit with its more complex microstructure were inconclusive with respect to the potential of hyperspectral scatter imaging for non-destructive assessment of the consumption quality. The estimated absorption coefficient spectra of the Braeburn apple fruits clearly showed the changes in chemical composition of the apples during CA storage over a longer period (up to 6 months) and shelf-life exposure (14 days). Mainly, these changes were observed as a decrease in the absorption coefficient values around 670 nm which was due to the degradation of chlorophyll during storage. Also, a clear decrease in the scattering properties of the apples was observed after 14 days of shelf-life exposure. However, no clear differences were observed in the optical properties estimated for the apples which had been stored under optimal and brown inducing CA storage conditions. This was explained by the fact that hyperspectral scatter imaging only probes the outer layers of the fruit, while the browning typically starts at the center of the fruit. Quantitative prediction of the internal apple quality in terms of soluble solids content (SSC) and fruit firmness (FF) based on respectively the bulk absorption coefficient and the reduced scattering coefficient did not result in higher prediction accuracy than prediction based on single point Vis/NIR reflectance spectra. The overall results clearly support a strong potential of the combination of the line-scanning hyperspectral scatter imaging technique with the computationally fast and accurate inverse metamodeling approach for fast, contactless and non-destructive optical properties estimation of food products to separate the information on the microstructure from that on the chemical composition.

664.017 --- Academic collection --- Properties of preserved foods and foodstuffs. Food quality --- Theses --- 664.017 Properties of preserved foods and foodstuffs. Food quality

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Most existing HVAC (Heating, Ventilation and Air Conditioning) systems control a spatial and temporal average level of environmental variable(s) (e.g., temperature, humidity and gas concentration, …) based upon feedback of inside environmental variable(s) measured at a single position in the whole room.Such control systems make use of set-points of these inside-environmental-variables that are assumed to be; (1), homogeneous inside the whole space of the indoor environment; (2), optimal for a defined theoretical population ‘average’ for the considered species of occupants. However, in reality, such environmental variables are never perfectly mixed but rather revealing a three-dimensional gradient due to the spatially and temporally heterogeneous heat and mass transfer phenomena inside the ventilated structures. Furthermore, living organisms (human, animal, plant or biological product) they are Complex, Individually different, Time-Varying and Dynamic ‘CITD’ systems. Consequently they are responding in individually different ways to changes in surrounding environmental variables rather than the ‘average organism’ concept due to several exogenous and endogenous variables, which also influence the bioresponses of these organisms. Every living organism reacts to its own individual ‘micro-environment’, which is defined as the collection of all environmental variables that reach the individual living organism. The micro-environment around the living organism is considered as a well-mixed-zone, which can be defined as the maximal 3D zone of improved mixing with acceptable low spatial gradients in heat and mass variables (micro-environmental variables such as temperature, humidity, …).A first part of this work focused on active control of the well-mixed-zone of temperature in a ventilated structure.The Data-Based Mechanistic approach was used to model the dynamic spatial temperature distribution of well-mixed-zone in a ventilated airspace to changes in the heat supply (control input). Dynamic response of indoor temperature to varying heat supply could be explained by a second-order transfer function model with a high coefficient of determination (R2T > 0.99), a low Young Identification Criterion (YIC < &#8722;2.3) and a low model standard error (SE < 0.028 &#9702;C). The physically meaningful model parameters as local heat load fraction (J/s) and the coefficient of thermal impedance (&#9702;C/J) were revealed. These two parameters were defining the relation between the heat and temperature spatiotemporal distribution inside the ventilated airspace (Chapter 2). The identified aforementioned data-based mechanistic models were the bases for a model-based control system to control the micro-environmental temperature in a ventilated test installation (Chapter 3). The designed control system (Proportional Integral Plus, PIP) was robust enough to control the temperature in different well-mixed-zones individually using ventilation rate and inlet temperature as control variables.By modifying the test installation, to increase the controllability of the system, it was possible to form and control two thermal well-mixed-zone of the same temperature (e.g., 37 oC &plusmn;1 oC) sandwiching another with a different temperature (e.g., 30.5 oC &plusmn;1 oC), simultaneously.A second part of this thesis focused on using the measured bioresponses of living organism to control the micro-environment around them.The bioresponses of individual living organisms to changes in their micro-environmental variables (mainly temperature) were modelled using the DBM approach (Chapters 4 and 5).The dynamic thermal bioresponses (eggshell temperature) of incubated chicken embryos were modelled from embryonic day 8 till embryonic day 19 to step changes in their ambient air te mperature. The incubated-embryo system was proposed in the present work to represent the incubated embryo and its surrounding micro-environment. It was shown that a first-order transfer function model was suitable (coefficient of determination, R2T > 0.98 and Young Identification Criterion, YIC < -10.2) to model the dynamic response (eggshell temperature) of the incubated-embryo system between the embryonic days 8 and 13. However, between embryonic days 14 and 19 a second-order transfer function model was more suitable to represent the dynamic response (eggshell temperature) of the incubated-embryo system, which was explained by the thermoregulatory effect of the developing embryo. Analogies between the incubated-embryo biosystem and physical systems (electric circuit and thermal systems) were used to quantify the physiological responses, thermoregulation and thermal capacity, during the biological processes. It was shown that the incubated egg acts as a reactive electric circuit to changes in its ambient temperature.The dynamic behavioural bioresponse (activity and position) of 7 days old broiler chickens in a ventilated chamber were modelled to stepwise changes in inlet temperature and ventilation rate(Chapter 5). A first-order transfer function model structure was suitable (coefficient of determination, R2T > 0.89 and Young Identification Criterion, YIC < -11) to describe the dynamic activity of the birds. It was noticed that the birds were tending to occupy the zones of low air velocity (< 0.2 m/s) when the inside temperature was lower than their thermal comfort temperature (< 28 oC) or when they were under cold stress. On the other hand, the birds were tending more to occupy the zones of higher air velocity when they were undergoing heat stress (>36 oC), which indicated a behavioural response to reduce their heat stress by moving to the zones of high air velocity to increase the convictive heat losses. It was possible to control the activity level and position of a group of chickens by changing their micro-environmental conditions (local temperature and air velocity). However, and surprisingly, by applying such control approach on the individual level it was found that the birds were tending to respond as one group instead of responding individually. Thus, we can say that the social effect of the group, flock behaviour, was more dominating than the micro-environmental effect on choosing their position in the room.A novel non-contact and motion tolerant technique was proposed and implemented in this thesis (Chapter 6) for real-time monitoring of embryo heart rate and vasodilatation and vasoconstriction in incubated eggs. Using a microscope camera (with 640 × 480 resolution) videos of the egg’s vascular structure were recorded with 10 frame per second from embryonic day 13 till embryonic day 19. Using image processing technique different embryogenic motions were captured in a form of time series of dynamic activity index. The measured heart rate of the chicken embryo was within the range (252-295 bpm) during the measurement period (between embryonic days 13 and 19).The cardiogenic signals were identified using signal processing techniques to calculate the heart rate of the embryo. The measured heart rate of the chicken embryo was within the range (252-295 bpm) during the measurement period.

Academic collection --- Theses