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МИНИСТЕРСТВО СЕЛЬСКОГО ХОЗЯЙСТВА И ПРОДОВОЛЬСТВИЯ РЕСПУБЛИКИ БЕЛАРУСЬ Учреждение образования «БЕЛОРУССКИЙ ГОСУДАРСТВЕННЫЙ АГРАРНЫЙ ТЕХНИЧЕСКИЙ УНИВЕРСИТЕТ» АГРОЭНЕРГЕТИЧЕСКИЙ ФАКУЛЬТЕТ Кафедра иностранных языков Реферат по дисциплине «Иностранный (английский) язык» (тема магистерского исследования: « Intelligent climate control for fattening pigs » «Интеллектуальное управление микроклиматом при откорме свиней») Специальность: 1-74-80-06 Энергетическое обеспечение сельского хозяйства Выполнил: Комик Д. В. Магистрант маг 21э от, АЭФ ________________________ (дата) (подпись) Проверила: Сысова Н.В., ст. преподаватель кафедры иностранных языков ________________________ (дата) (подпись) МИНСК 2022 Abstract The abstract examines the conditions of detention in pig farms. Existing technologies for keeping pigs are considered. It is indicated that maintaining the microclimate in the room prevents diseases of pigs and improves the growth of young animals.This paper is of interest to technologists, engineers and master degree students. Аннотация В реферате исследуются условия содержания в свиноводческих фермах. Рассматриваются существующие технологии содержания свиней. Указывается, что поддержание микроклимата в помещении, предотвращает болезни свиней и улучшает прирост молодняка. Данная научная работа представляет интерес для технологов, инженеров и магистрантов. Анатацыя У рэфераце даследуюцца ўмовы ўтрымання ў свінагадоўчых фермах. Разглядаюцца існуючыя тэхналогіі ўтрымання свіней. Указваецца, што падтрыманне мікраклімату ў памяшканні, прадухіляе хваробы свіней і паляпшае прырост маладняка. Дадзеная навуковая праца ўяўляе цікавасць для тэхнолагаў, інжынераў і магістрантаў. CONTENTS INTRODUCTION……………………………………………………...4 I. Conditions for maintaining the microclimate in pig houses ….…..5 II. Innovative technical means and equipment for for pig houses in livestock farming…………………………............................………………….10 CONCLUSION………………………………………………………..13 REFERENCES………………………………………………………..14 INTRODUCTION Pig farms have the challenge of providing environmental comfort to the animals, aiming at the productive benefits The environment has great influence on the welfare of the pigs, an improper environment causes discomfort to the animals. The low level of animal welfare can affect production, reproduction, health and quality of the final product.Ambience is the science that analyzes the characteristics of the environment as a function of the thermal comfort zone of the species, associated with physiological characteristics that regulate the internal temperature of the animal The knowledge and identification of climatic variables that directly influence the performance of the animal in the form of thermal stress are the main measures to seek out and execute mitigating measures of discomfort and loss of production.Pigs grow and function better under thermoneutral temperature conditions. Pigs exposed to temperatures outside the thermoneutral zone may have behavioral and physiological changes, consequently reducing weight gain Studies by found that in a situation of thermal stress, the immune system of the animals becomes weak, resulting in an inefficiency to resistance to infections.The objective of this study was to evaluate the thermal comfort of growing and finishing pigs in facilities with different types of floors. I. CONDITIONS FOR MAINTAINING THE MICROCLIMATE IN PIG HOUSES Indoor climate in pig husbandry Most of the 122 million pigs in the European Union are kept indoors, to protect them from negative environmental impacts and to control their environment in order to optimise production. Generally, this results in much better animal performance compared to outdoor production Furthermore, keeping pigs indoors enables the manure to be collected and reduces pollutant emissions. The climate in livestock buildings has to be controlled , and the key process for that is ventilation. The problem is that an adequate control of air distribution in the 3-dimensional space occupied by animals, is still lacking. Therefore, this thesis focuses on the relationship between the 3-dimensional ventilation and the optimal climatic environment for weaned piglets. The standard pig house is subdivided into rooms containing a number of pens. Each room houses a batch of pigs of the same age and therefore with the same thermal needs. Piglets are born in a farrowing room, and when 4 weeks old (bodyweight circa 8 kg) are moved to a room for weaned piglets. At 10 weeks of age (25 kg) they are moved to the grower-finisher room. Commonly, indoor climate is controlled per room primarily by controlling the ventilation rate and additionally by heating. It is extremely important to keep weaned piglets in the right climatic environment. Directly after weaning these animals are subjected to many stresses, including being separated from the sow, being moved, and changing from milk to a solid diet In addition, after the first few days it is important that the climate is right, as production results and health are negatively affected by adverse climatic conditions Ventilation systems for weaned piglets The most common ventilation systems in rooms for weaned piglets are mechanical systems in which fans extract the air from the room. Fresh air enters the room via an air inlet system, and the type of air inlet system generally determines the air distribution in the room. In the Netherlands three types of air inlet systems are common in rooms for weaned piglets. The first is porous ceiling ventilation, primarily based on mixing of fresh air with room air. It is generally applied in rooms with fully slatted floors. Fresh air enters the room through small ducts in the ceiling or through a porous part of the ceiling The other two systems are primarily based on displacement of air and are generally used in rooms with partly slatted floors. Door-ventilation uses the operator walkway in the room as an air inlet channel; fresh air enters the room through an opening in the door Ground channel ventilation supplies fresh air via an under floor air duct and through openings in the floor of the operator walkway In recent years, interest in this system has increased. All systems have a problem relating to the 3-dimensional ventilation and air supply to the animals Climatic demands of pigs The climatic environment can be subdivided into two aspects. The first is the thermal climate of the pig, which is determined by air temperature, air velocity and heat transfer due to conduction (example: floor heating) or radiation (example: heating lamps). The second aspect is air composition (air quality), i.e. the concentration of contaminants and oxygen in the air. Typical aerial contaminants in pig rooms are ammonia, carbon dioxide, dust and vapour. A widely accepted range for the optimal thermal climate for the pig is defined as the Thermo Neutral Zone (TNZ), which is the range of thermal conditions in which the metabolic rate of the pig is minimal The limits of the TNZ depend on animal characteristics such as body weight and feed intake. They are mostly expressed in air temperature, but factors like air 3 Chapter 1 velocity and radiative heat loss are important as. Another problem is that the effect of periodical short-term exposure of the piglet to conditions outside the TNZ is unknown. Furthermore, in an optimal climatic environment, the concentrations of contaminants such as ammonia, carbon dioxide and dust should be as low as possible or at least below defined limits There are four practical reasons why creating an optimal climate is so important for the pigs. • Production efficiency: It is known that climatic conditions influence feedintake, growth and feed conversion ratio of pigs. In cold conditions, more energy is needed to maintain the body temperature, which has a negative effect on the feed conversion ratio Under hot conditions outside the TNZ, the pigs will eat less and therefore grow slower Also, high concentrations of dust and ammonia are known to reduce performance . • Animal health: Climatic conditions are known to influence the health of the animals. Periods of cold conditions outside the TNZ or high concentrations of bacteria (attached to dust particles) in the air can cause respiratory and other diseases, resulting in more use of medicine and a higher mortality When pigs are ill, production efficiency and animal welfare are obviously reduced. • Animal welfare: Climatic conditions in terms of thermal comfort and availability of fresh air affect animal welfare directly In choice tests pigs prefer fresh air above air containing ammonia. Adverse climatic conditions can cause tail biting. • Pen fouling and emissions: Under warm conditions, pigs in pens with a partly slatted floor tend to lie on the cooler slats. As a result, they will dung and pass urine on the solid floor, which causes pen fouling unhygienic conditions, higher concentrations of the contaminant ammonia in the air and higher emissions of ammonia Microclimate It is known that the air in a ventilated room is never homogeneously mixed. There are zones of different climatic conditions, especially in a densely populated pig-room with a high internal heat production. Near the inlet of fresh air the temperature and the concentration of contaminants will be relatively low. Near the sources of heat and contaminants (animals, manure) both temperature and contaminant concentrations will be higher. The airflow pattern in the room determines the temperature and contaminant distribution in the room and is linked to the occurrence of climatic zones. The climatic zones of concern in a pig room are the zone where the pig farmer does his work (working conditions) and the zone where the animals live: the Animal Occupied Zone (AOZ). The AOZ is roughly the zone between 0 and 50 cm above the floor of the. In this thesis the focus is on the climate in the AOZ, i.e. the microclimate. It is distinguished from the macroclimate in the room, which is the average climate of the room. The ability to create and maintain an optimal climate in the AOZ is probably the most important aspect of ventilation system performance especially in rooms for weaned piglets. Although this factor is so important, very little is known about patterns of the climatic conditions the piglets are exposed to when housed in rooms with different ventilation systems. The research described in this thesis sets out to rectify this Contaminant and Heat Removal Effectiveness of Three Ventilation Systems in Nursery Rooms for Pigs Air quality and quality of the microclimate in a pig facility can be characterized by the concentration of contaminants (e.g., ammonia, dust, and bacteria) and by the air temperature, humidity, and air velocity in the animal occupied zone (AOZ), since high concentrations of contaminants and/or high temperatures negatively affect animal health and animal production Too low air temperatures or high air velocities (draft) in the AOZ also significantly affect animal health, animal behavior, and animal production, especially for weaned piglets . Climatic factors are also technical indicators related to animal welfare and pigs prefer fresh air above ammoniated air .The air within a pig facility contains contaminants, moisture, and heat released by animals, feed, floor surface, and slurry. Contaminated air, moisture, and heat are removed through ventilation. The ventilation system distributes fresh air in the building. The effectiveness with which contaminants and heat are removed by various ventilation systems needs to be well understood. Improving ventilation effectiveness is an important strategy for reducing contaminant concentrations in animal houses . Several ventilation system designs are commonly used in pig rooms. However, little is known of the relationship between the air displacement in the AOZ and the ventilation system design, which determines the airflow pattern in the room. Mathematical models (CFD) predict airflow patterns in empty test rooms without obstacles The complex environment of an occupied pig room, where animal presence and animal activity significantly affect airflow pattern characteristics and the distribution of contaminants, has not been simulated. Research relying on practical measurements has shown that displacement ventilation without mixing provides more fresh air to the zone of occupancy than dilution ventilation, which ideally requires perfect mixing (Breum et al., 1989), and that a sidewall inlet combined with a high outlet, and thus an upward flow, more effectively removes certain contaminants from the central operator walkway than a downward flow Practical measurements have also shown that the location of the sources of contaminants in the pig room has important effects on contaminant concentration levels and distribution. For example, contaminant concentration (including ammonia and CO2) measured by Lavoie et al. 13 Chapter 2 (1997) at 1.5 m above the floor of the operator walkway in the center of a pig room showed that significantly lower concentrations could be achieved by locating the air outlet near the source of the contaminants. Measurements have also been used (Aarnink and Wagemans, 1997) to determine that the air quality (measured in terms of ammonia and dust) in pig facilities is better with a low air inlet, in the floor of the operator walkway, and a low air outlet than with a high diffuse inlet combined with a high outlet. The research presented below uses practical measurements to gain insight into airflow patterns and effectiveness of ventilation in the AOZ for three ventilation systems commonly used in nursery rooms for pigs. Air quality measurements (CO2 and temperature, excluding air velocity) in the AOZ of each system were taken for three batches of weaned piglets under practical conditions. There were differences in CRE and HRE among the three experimental rooms. The room with ground channel ventilation showed the highest value of CRE and HRE and the lowest CO2 concentration in the AOZ (table 4), even while this room had the highest inlet concentration . Similar results were found by Aarnink and Wagemans (1997), who compared a room with ground channel ventilation and a low outlet with a room with porous ceiling ventilation and a high outlet. Ground channel ventilation showed better air quality in the AOZ. The results of Breum et al. (1990) also indicated that ventilation systems in a pig facility with a low air inlet and a high air outlet, and thus an upward airflow, gave more effective ventilation than a downward flow. Ventilation system design has an effect on the air quality in the AOZ. A high CRE, resulting in lower contaminant concentrations under cold conditions with minimal ventilation, and a high HRE, resulting in lower temperatures under warm conditions with high ventilation rates, are expected to improve animal performance and animal welfare. This was not determined in the research because the experimental design was not suitable for this. Ongoing research focuses on this topic. The values of CRE and HRE are not solely dependent on ventilation system design. One very important factor is the measurement location, as illustrated by comparison of the results from the different sampling points in each room. The average CRE and HRE values in the AOZ would give a better impression of the effectiveness of the air displacement, but it is difficult to measure CO2 concentrations in the AOZ. Systems with high values of CRE and HRE, indicating effective ventilation in the AOZ, can use lower ventilation rates. This can be illustrated by the climate settings used in this research the ventilation settings used in the room with ground channel and door-ventilation were lower than in the room with porous ceiling ventilation. This can be an important aspect in reducing costs for air scrubbing, which is one way to reduce emissions from livestock facilities effectively. Effective ventilation can be realized by locating the air inlet close to the AOZ. This might increase the risk for high air velocities, or drafts, in the AOZ. Air quality and thermal comfort are both important factors in creating a healthy microclimate and preventing problems with animal health, animal welfare, and sub-optimal production. To evaluate the performance of a ventilation system, the measurements should include draft measurements, and the sampling 27 Chapter 2 points should be located in such a way that they give information about the entire AOZ. A possible strategy for choosing the measurement locations is to carry out a preliminary study in the experimental room, in which one permanent sampling location is chosen close to the lying area of the animals and a movable set of sensors is used at several other sampling locations. Comparing the simultaneous measurements from the reference location and the other sampling locations should provide information on the variation within a pen and on the representativeness of the reference location chosen. Conditions for keeping animals A batch of 36 was fattened in an experimental farm in Liège (Belgium), from 34 to 122 kg on average, during a 3 months period from October 22nd, 2011 to January, 23rd, 2012, corresponding to fall and winter seasons in Belgium. The batch was divided into 3 homogeneous groups of 12 animals according to the sex and the body mass. Groups were kept separately in three identical rooms (30 m2 , 103 m3 ) equipped with a 9 m2 -pen (0.75 m2 per pig) with concrete slatted floor. The manure was collected under the flooring surface and evacuated only at the end of the finishing period. Each pen was equipped with two feeding troughs with free and unlimited access. Each pen was ventilated using an extraction fan whose flow was automatically adapted to keep constant the ambient temperature. The fresh air entered by an opening which communicated with the service corridor. Ventilation rates and ambient temperature were continuously monitored and recorded with an Exavent apparatus (Fancom, Panningen, The Netherlands). II. INNOVATIVE TECHNICAL MEANS AND EQUIPMENT FOR FOR PIG HOUSES IN LIVESTOCK FARMING Electronic nose In one pen (pen 2), a sample tube was also dedicated to anelectronic nose (e-nose) measurement. The signals were recorded at a sampling frequency of 1 measurement each 5 min whole campaign. An electronic nose is an intelligent device based on an array of non-specific gas sensors and a signal processing system. When sensors responses are put together, they form a pattern, which is typical of the gas mixture presented to the array,like a signature. Hence, e-nose is not an analytical instrument, aiming at measuring the concentration of various chemical compounds. In the signal processing step, the whole signal pattern is always used as a global response. The instrument was developed in the university research laboratory and consisted in a six-sensor metal-oxide sensor array (Figaro) arranged in a PTFE 200 mlchamber. The ambient air is sucked with a pump placed after thesensor chamber at a flow rate of 200 ml min1 The useful signal ofeach sensor is its electrical conductance, which is recorded, onboard saved andoff-line processed by statistical package (Statistica). the application suggested by the manufacturer. Remembering that sensors have only partial specificity to those compounds (sometimes odourless), they were chiefly selected from the experience of the research group within the domain of odour monitoring Relevance of electronic nose Obviously, the link between electronic nose response and odour concentration is not straightforward. However with some precautions in the design and in the use of sensor arrays, it is possible to approach the human nose perception of the odour level. A first condition is the right choice of the application for which the “chemical” concentration should be correlated to the odour concentration. Such condition is generally fulfilled for waste or fermentation odours, such as pig farm emissions. There is a quite linear relationship between odour concentration and chemical response, as measured by gas sensors, through that is not true for all odour sources. A second condition is the right choice of the sensors in the array. In the present study, the 6 tin oxide sensors were selected for their good sensitivity to chemicals involved in the odour of pig barns, according to previous experience of the research team. Fig. 9 shows the relation between the odour concentration measured by dynamic olfactometry and the Mahalanobis distance, calculated in the 6D-space of sensor signals, of the observations in the pen from ones in an odour-free air. The two variables are estimated independently one from the other, but the coefficient of determination of the linear model between them is quite high (R2 ¼ 0.78). So, in this specific case, the distance from an odour-free group of observations should already be sufficient to estimate the odour concentration. But the third and major condition to really acknowledge the electronic nose as a “nose” is the right choice of a robust and validated mathematical model of data processing. Here, a link between sensor signals and odour concentration was obtained through a regression procedure. The 1-component PLS model gave very good results in cross-validation and can be considered as sufficiently robust to assess the odour concentration in the pig pen. In the present study, the odour measurements conducted in the specific case of experimental barns provide results which could be regarded as almost independent of ambient parameters, such as temperature (inside and outside), humidity and even ventilation rate. As these parameters do not vary significantly, they have low influence on both the response of e-nose sensors and the odour emission itself. Hence, the time evolution of the odour emission factor can roughly be directly deduced from the variation of the odour concentration inside the pen (about independently of the Fig. 6. Diurnal patterns of assessed odour emission factor for two typical days. Fig. 7. Histogram of hour occurrences of the maximum assessed odour concentration during the day. 940 A.-C. Romain et al. Atmospheric Environment Snapshot olfactometric measurements conducted at different stages of pig growth clearly indicate that the odour emission factor increases about linearly with the pig mass. The value of 20 ou s.pig1 at the finishing stage, adopted in some European guidelines, appears to be credible for the breeding system considered in this study. The most significant outcome of the present study is the confirmation of the high diurnal variation of odour emission rate, which is chiefly due in the studied case to the circadian rhythm of pig. Hence, it is unlikely that a representative odour concentration and emission rate (i.e., a daily mean) can be obtained using a snapshot measurement. As concluded by Schauberger et al. (2013), previously published odour emission rates are likely to show a bias towards higher values since most of the measurements were taken during daytime and in warm weather. The lowest odour level is actually observed during the night, when usually more stable outdoor atmospheric conditions occur. Therefore, considering such variability of the odour emission in dispersion modelling may lead to some differences in the assessment of the area of the annoyance zone. For long term studies, e.g. on an annual time base, however, the higher odour emission rates recorded during the day should balance the shorter extend of the night-time plume. Simulating (with Tropos Impact) a 2000 pigs barn with a constant 20 ou s.pig emission factor or with a typical diurnal pattern, but with the same daily average odour emission rate, gives rise to about the same 98th percentile shape for a typical Belgian climate. The influence of diurnal variation should be more marked when considering short term plumes, especially when night and day wind patterns are very different hen used cautiously, the electronic nose, fitted with appropriate gas sensors and with a suitable odour assessment model, validated against acknowledged measurement methods, proves particularly convenient to continuously monitor an odour emission. In the present study, it was chiefly useful as complementary tool to dynamic olfactometry to record the daily variation of the odour concentration in the pig barn which, when multiplied by the measured ventilation rate, provides the odour emission factor. Diurnal patterns of pig activity for the two days considered in Fig. Relation between the Mahalanobis distance from a non-odorous air group in the 6D-space of sensor signals and the odour concentration measured by dynamic the controlled conditions of the experimental pens, the daily variation of the odour emission rate could be mainly attributed to the sole influence of the circadian rhythm of pig. As a consequence, determining a representative odour emission factor in a real case cannot be based on a snapshot odour sampling, even modulated by the variation of the ventilation rate. The odour emission in a pen is likely to vary up to a factor 5 between quiet periods (e.g. night) and activity periods (e.g. late afternoon). Depending on the sampling time, the average odour emission rate could be largely over or under estimated. To improve the estimation of odour concentrations and odour annoyance zones by dispersion models, not only the annual variation of the odour release has to be taken into account, but also the diurnal one. According to the measurements conducted during this study, this time evolution should be better accounted for by a step variation (e.g. low odour before 8:00 and after 21:00 and higher between) than by a true sinusoidal function. As mentioned, the advantage of experimental barns over real farms is that many parameters are controllable. However, essential outcomes may be extrapolated to farms as experimental conditions were as much as possible representative of real cases. So, the odour emission factor of 20 ou s.pig the finisher pig can be considered as a plausible value, at least for slatted systems. CONCLUSION It is extremely important to keep weaned piglets in the right climatic environment for animal health, animal performance and animal welfare. Ventilation is the key process in climate control in rooms for weaned piglets. This thesis focuses on the relationship between in the 3- dimensional ventilation and the optimal climatic environment for weaned piglets, regarding the two aspects of climate: thermal climate and air composition. The optimal thermal climate for the pig is defined as the Thermo Neutral Zone (TNZ). Furthermore, in an optimal climatic environment, the concentrations of contaminants such as ammonia, carbon dioxide and dust should be as low as possible. The air in a ventilated pig room is never homogeneously mixed. The airflow pattern in the room determines the 3 dimensional temperature and contaminant distribution in the room and is linked to the occurrence of climatic zones. The climatic zone of concern is the zone where the animals live: the Animal Occupied Zone (AOZ) roughly the zone between 0 and 50 cm above the floor of the pen. In this thesis the focus is on the climate in the AOZ, i.e. the microclimate. It is distinguished from the macroclimate in the room, which is the average climate of the room. In the Netherlands three types of ventilation systems are common in rooms for weaned piglets, i.e. porous ceiling ventilation, door-ventilation and ground channel ventilation. The ability to create and maintain an optimal climate in the AOZ is probably the most important aspect of ventilation system performance. Although this factor is so important, very little is known about patterns of the climatic conditions the piglets are exposed to when housed in rooms with different ventilation systems. The objective of this research was to improve microclimate for weaned piglets by answering the questions how to measure, evaluate and control the microclimate in rooms for weaned piglets. All experiments in the study we conducted under normal farming conditions in fully operational rooms with weaned piglets References Aarnink, A.J.A., and M.J.M. Wagemans. 1997. Ammonia Volatilization and dust concentration as affected by ventilation systems in houses for fattening pigs. Trans. ASAE 40(4): 1161-1170. Aarnink, A.J.A., J.W. Schrama, R.J.E. Verheijen, and J. Stefanowska. 2001. Pen fouling in pig houses affected by temperature. In: Proc. of 6th Livestock environment symposium, pp: 180-185. Louisville, Kentucky, 21-23 May 2001. CIGR. 1999. CIGR Handbook of Agricultural Engineering. Animal Production and Aquacultural Engineering, Vol. 2. St. Joseph, Mich.: ASAE. Collin, A., J. van Milgen, S. Dubois, and J, Noblet. 2001. Effect of high temperature and feeding level on energy utilization in piglets. J. Anim. Sci. 79: 1841857. Collin, A., M.J. Vaz, and J. Le Dividich. 2002. Effects of high temperature on body temperature and hormonal adjustments in piglets. Reprod. Nutr. Dev. 42: 45-53. Donham, K.J., and D. Cumro. 1999. Setting maximum dust exposure levels for people and animals in livestock facilities. In: Proceedings of International Symposium on “Dust Control for Animal Production Facilities,” 93-110, 30 May – 2 June, Aarhus, Denmark: Danish Institute of Agricultural Sciences. Drummond, J.G., S.E. Curtis, J. Simon, and H.W. Norton. 1980. Effects of aerial ammonia on growth and health of young pigs. J. Anim. Sci. 50(6): 1085-1091 |