Uninsulated Buildings Research Articles

SE—Structures and Environment: Diurnal Variation in Ammonia, Carbon Dioxide and Water Vapour Emission from an Uninsulated, Deep Litter Building for Growing/Finishing Pigs

In an uninsulated livestock building with natural ventilation, the air temperature and airflow show a large variation according to the daily variations in weather and season. The objective of this investigation was to determine the diurnal variation in the emission of NH3, CO2 and moisture from an uninsulated building with a deep litter system for growing/finishing pigs and to investigate the influence of air temperature and airflow rate on the NH3 emission. The investigations were carried out in an uninsulated experimental building with 125 growing/finishing pigs in deep litter pens. The building was 12 m wide and 20 m long (240 m2), naturally ventilated but also equipped with exhaust fans. The NH3 concentration, the CO2 concentration, the outside and inside air temperature, the outside and inside relative humidity and the animal activity were measured continuously during 6 days at a constant airflow rate of 146 m3 m−2 h−1. During six nights the effect of airflow rate on the NH3 emission was investigated by changing the airflow rate in steps from 26 to 165 m3 m−2 h−1. The measurements were carried out between day 16 and day 46 from the beginning of the growing period. The NH3 emission from an uninsulated, deep litter building for growing/finishing pigs showed a clear diurnal variation. During the 6 days with constant airflow rate the emission varied from 6 to 247% of the mean, with the minimum around 6.00 a.m. and the maximum around 5.00 p.m. The daily mean of NH3 emission increased from 0·23 to 0·65 gh− per pig (day 16–day 43). The diurnal variation of NH3 emission was correlated to the inside air temperature (correlation coefficient rs=0·86–0·91) and the animal activity (rs=0·69–0·83). The increase of NH3 emission with the air temperature followed an exponential pattern. The relative NH3 emission flux increased from 0·2 to 2·0 between the air temperatures −2 to 14°C inside the building. An increase in airflow rate through the building from 26 to 165 m3 m−2h−1 increased the relative NH3 emission flux from 0·4 to 1·4. The CO2 emission during the 6 days at constant airflow rate had a daily mean between 81 and 120 gh−1 per pig with a diurnal variation from 61 to 249% of the mean. The CO2 emission was correlated to the inside air temperature (rs=0·42–0·83) and animal activity (rs=0·67–0·85). The daily mean of water vapour emission increased during the same days between 146 and 408 gh−1 per pig and varied from 18 to 269% of the mean. The water vapour emission was correlated to the inside air temperature (rs=0·53–0·97), animal activity (rs=0·57–0·85) and the water absorption capacity of the inlet air (rs=0·27–0·94). The diurnal variations in NH3, CO2 and water vapour emission were correlated to each other.

SE—Structures and Environment: Deep Litter Systems for Beef Cattle housed in Uninsulated Barns, Part 2: Temperatures and Nutrients

The litter used in the deep litter of uninsulated buildings in beef production is expensive. Different litter materials and their mixes have different characteristics. It was determined that the optimum mix of straw, peat and wood chips would reduce litter consumption and still meet the animals' requirements for a thermal environment in a bench-scale study simulating the deep litter in a partially littered pen. However, this appeared to be impossible. The size of the test vessels was 60 cm by 60 cm. There were five different combinations of litter mix of straw, peat and wood chips involved in the trials. The simulation was based on the assumption that the space allowance per suckler cow in the pen was 3·5 m2on deep litter and 4·0 m2on the dung alley and manure (27·5 kg day−1) was deposited evenly in the pen. The temperatures at three heights were measured and the highest and the average temperatures as well as the temperature profiles of the deep litter were determined. Changes in the nutrient, carbon, moisture contents, losses and mass were measured.The difference in physical structure between the five litter mixes tested did not cause any difference in the composting processes of the mixes. The difference in the chemical composition of the mixes did, however, cause a difference. The deep litter consisting of mixes with a high proportion of straw reached a high composting temperature because the straw contained more organic carbon than did the other components. The input of organic carbon into deep litter should be at least 800 g m−2day which is about 8·8–10·2 kg of litter per day and per suckler cow in an optimized partially littered pen. Hence, rather than reducing the litter consumption of deep litter, it should be increased.

SE—Structures and Environment: Solar Heat Load in Uninsulated Livestock Buildings

High environmental temperatures affect animal productivity. Even in northern Europe, especially uninsulated livestock buildings may reach high air temperature levels during warm and sunny days in the summer due to the heat gain by solar irradiation. The objective of this research was to determine the solar heat load, the ratio of solar heat utilization, the absorptance factor, the transmittance–absorptance factor and the overall heat transfer coefficient per m2of floor area for an uninsulated building. Two studies were made in the same building but with different roof claddings. In the first study, both the wall cladding and the roof cladding were transparent polycarbonate double web sheets (U -value of 3·0 Wm−2K−1). In the second study, 85% of the roof cladding was changed to non-transparent black fibre cement sheets. The outside and inside air temperatures, the temperature in the exhaust airflow and the solar irradiation against a horizontal surface were measured continuously. The specific airflow was changed in steps between 0·0017 and 0·027 m3m−2s−1.The temperature difference had a maximum about 1–2 h later than the maximum solar irradiation. The ratio of solar heat utilization, defined as the fraction of solar irradiation against the building envelope that is transferred to sensible heat in the air volume, varies due to the ventilated airflow through the building. A higher airflow results in a higher utilization. The transmittance–absorptance factor for the building with transparent polycarbonate roof was 0·36 and the absorptance factor for the building with non-transparent fibre cement roof was 0·20. The overall heat transfer coefficients per m2of floor area for the same buildings were 11·0 and 12·5 Wm−2K−1, respectively.

The influence of day length and temperature on food intake and growth rate of bulls given concentrate or grass silage ad libitum in two housing systems

AbstractIn order to study the effect of day length and temperature on performance, data from 495 growing, non-castrated bulls of the Swedish Red and White breed were analysed. Groups of 11 bulls were housed in either an insulated building in pens having slatted floors or in an uninsulated building with pens having both a deep straw bed and a concrete floor. The majority of the bulls (330) were given a concentrate diet ad libitum, while the remainder (165) were given grass silage ad libitum supplemented with concentrate. Energy intake, live-weight gain, housing temperature, day length and change in day length were calculated as 14-day period means for the two housing systems. Regression analyses showed that live-weight gain was associated with increasing day length in bulls on both feeding treatments. For bulls given concentrate ad libitum, metabolizable energy intake was associated with increasing day length. The intake of heavier animals was more influenced by day length than that of those which were lighter. The seasonal influence on daily energy intake in bulls given silage did not show the same pattern as for bulls given concentrate ad libitum. The intake was highest in June and lowest in December for the bulls given concentrate but for the bulls given silage it was highest in August, September and October and lowest in March and April. This was due to the varying quality of the grass silage over the year. No effect or very little effect of temperature or housing system on energy intake or on weight gain was found.

Potential of Tree Shade for Reducing Residential Energy Use in California

Electric utilities in California currently sponsor planting of approximately 75,000 yard trees annually as an energy conservation measure. In this study we evaluated the potential effects of tree shade on residential air conditioning and heating energy use for a range of tree orientations, building insulation levels and climate zones in California using computer simulation. Trees shading a home's west exposure produced the largest savings, both annual (kWh) and peak (kW), for all climate zones and insulation levels considered. Next largest savings were for southwest (annual and peak) and east (annual only) locations. Three trees (two on the west, one on the east side) reduced annual energy use for cooling 10 to 50 percent (200 to 600 kWh, $30 to $110) and peak electrical use up to 23 percent (0.7 kW). Except in climates with little air-conditioning demand, cooling load reductions were always greater than increased heating loads associated with shade from south side trees in winter. Air-conditioning savings, both peak and annual, were larger in warmer climates and uninsulated buildings; percentage savings were larger in cooler climates and for more energy efficient buildings. Recommendations are made regarding locating yard trees to maximize energy savings.

Insulated and Uninsulated Housing Systems for Growing Bulls Fed Grass Silage ad Libitum

Abstract A total of 165 group-fed bulls of the Swedish Red and White breed were used to investigate differences in weight gain, feed intake, feed conversion, carcass traits and health when housed either in an insulated building with slatted floors in the pens or in an uninsulated building with partly deep-littered pens. The total pen area was 1.5–2.3 m2/bull in the insulated building and 3.6–5.8 m2/bull in the uninsulated building. The animals were fed a restricted amount of concentrate which was calculated to cover 50% of the energy requirement and grass silage ad libitum. They were slaughtered at about 470 kg live weight. There was no significant difference between animals in different buildings either in live weight gain, feed intake or feed conversion, but animals in the uninsulated building had significantly less fat in the carcass hindquarters than the others. At slaughter, significantly more pneumonic lesions were found among bulls in the insulated than in the uninsulated building, but this difference did not influence daily live weight gain or the amount of carcass dissectible fat. The conclusion was that animals in the uninsulated building had a higher energy requirement for maintenance and activity than the others and that the main reason for this was the difference between buildings in area per animal and in pen design.

Two Housing Systems for Intensively Reared Bulls Slaughtered in Two Weight Ranges

Abstract 510 group-fed bulls of the Swedish Red and White breed were used to investigate differences in production and health when housed either in an insulated building with slatted floors in the pens or in an uninsulated building with partly littered pens. Two stocking densities, 11 versus 15 animals/pen, were studied as well, but only in the uninsulated building. The animals were fed concentrate ad lib., 0.5 kg/d of roughage, and were slaughtered at about 220 kg live weight (bull calves) or at about 420 kg live weight (bulls). The comparison between buildings showed no significant differences either in feed intake or in live weight gain. Feed conversion, if calculated as MJ metabolizable energy/kg live weight gain, was significantly poorer for bull calves (but not for bulls) in the uninsulated building. If calculated as MJ metabolizable energy/kg carcass gain, there was no significant difference in feed conversion between animals in different buildings. Animals in the uninsulated building had less fat in the carcass than the others. Bull calves had significantly more liver abscesses in the insulated building than in the other. Bulls were treated for pneumonia and interdigital phlegmon more often in the uninsulated than in the insulated building. Animals in the uninsulated building had a higher energy requirement for maintenance and activity than the others. The main reason for this was probably the difference between buildings in area per animal and pen design. The higher stocking density resulted in a lower growth rate of the bulls.

The effect of different housing systems and feeding regimes on the performance and rectal temperature of sheep

AbstractThe effect of insulated (IN) and uninsulated (UN) buildings on food intake, performance and body temperature of sheep was studied over 4 years. The lowest average monthly temperature was -13·1°C. In the UN the temperature was on average 6-6°C higher than outside but the temperature in the IN remained fairly constant and was close to 10°C. Summarized for all 4 years the roughage intake was proportionately 0·02 higher in the UN than in IN (P > 0·05). There was no effect of treatment on weight gain, but the weight of the fleece was higher in IN than in UN (1·74 kg v. 1·66 kg per sheep). The mean age at first oestrus was 222 days. There was no difference in the length of pregnancy and lambing percentage was 185% in both treatments. The average birth weight was higher for lambs born in UN than IN (5·10 v. 4·95 kg), but the weight at weaning was the same. On only one occasion was the rectal temperature lower for ewes in UN than IN before shearing (38·7°C v. 39·2°C). After shearing no effect of treatment was found except for the 1st year, but in year 2 there was an interaction between plane of nutrition and housing. Results clearly indicated that uninsulated buildings are well suited for sheep.

Evaluation of animal health in beef production in relation to housing and feeding systems

The effects of 2 different housing systems and 2 different feeding regimes on animal health was evaluated during a 3 year period. An insulated building with boxes with slatted floor was compared with an uninsulated building with boxes with straw bedding. Two different feeding regimes were used in both barns: concentrates ad lib and 0.5 kg roughage/calf and hay or grass-silage ad lib and 1 kg concentrates/100 kg live weight daily. There was no significant difference in disease incidence in the 2 housing systems except a higher incidence of interdigital phlegmon in bulls from the uninsulated building with straw bedding. The number of treatments against pneumonia and interdigital phlegmon was lower in the groups of bulls fed silage ad lib. Pneumonic lesions, liver abscesses and reactions in the rumen were more frequent in the groups fed concentrates ad lib in contrast to the silage-fed bulls. It was concluded that the present investigation thus indicates an increased susceptibility to infections of the bulls fed concentrates ad lib.

Thermoregulatory behaviour of sheep housed in insulated and uninsulated buildings

The objective of this study was to investigate the thermoregulatory behaviour of sheep in confinement. In Experiment 1, two groups of 8 lambs in both an insulated (IN) and uninsulated (UN) house (total 32 animals) were studied; the durations of lying with and without body contact and standing were recorded (24 h time-lapse video recording) for five selected days before and after shearing (40 24-h periods). Before shearing the lying time was significantly longer in IN than UN (917.2 min day −1 and 862.1 min day −1 respectively). The first day after shearing the lying time was reduced by 39%, but approached the level before shearing around 25 days later. There was no difference between IN and UN. In Experiment 2, the body and head posture and the number of physical contacts (huddling) when lying was recorded at noon every day. Around 90% of the sheep before shearing were lying with all legs hidden under the body, and there was no difference between IN and UN. Huddling was more pronounced in UN. In Experiment 3, a group of 12 lambs could choose between two pens (Pen A with wooden slatted floor and Pen B with an expanded metal floor). Before shearing the lambs showed no preference. The first day after shearing the lambs did not lie down at all, and later they almost exclusively preferred to lie at the wooden slats. This study shows that the main thermoregulatory strategy for sheep exposed to low temperatures, especially after shearing, is to reduce the lying time. Huddling was exploited to some extent, but the results showed that the sheep did not utilize the strategy of changing lying posture and time of day for lying.

Changes in Seed Germination With Time for Polycross Progenies of Cicer Milkvetch

Relatively few seed‐longevity studies have been concerned with differences among cultivars or genotypes within a species. The purpose of this study was to evaluate the change, if any, in longevity and early seedling vigor of cicer milkvetch (Astragalus cicer L.) seed from selected populations when stored at ambient temperature in an unheated, uninsulated building and subsequently germinated at high (15/25 °C) and low (5/20 °C) alternating temperatures. Seed of polycross progenies from four populations were evaluated for rate of germination when the seed were about one year of age and after 12 yr of storage. Percentage seed germination on a daily basis through Day 14 after planting and total germination at 15/25 °C were similar for the four populations and for the 1‐ and 12‐yr‐old seeds. Progenies within populations differed significantly (P ≤ 0.05) for rate of germination except on Day 14 after planting with 1‐year‐old seed. Germinability on Day 14 ranged from 87 to 100% after 12 yr of storage. When evaluated at 5/20 °C, large differences were noted among populations and among progenies within populations for both rate of germination and total germination. This indicates that the populations and progenies within populations differed genetically for rate of germination. Genetic differences among populations were expressed at 5/20 °C, but not at 15/25 °C. The decline in early seedling vigor as measured by rate of germination at 5/20 °C suggests that care should be taken when increasing the seed supply with older seed from a synthetic cultivar of cicer milkvetch and, perhaps, with seed of other species held in a seed storage facility.

The thermal behavior of thermally insulated and uninsulated buildings

The thermal behavior of the walls and roofs of thermally insulated and uninsulated buildings in hot humid climates was experimentally investigated. Two identical housing model huts were built, one insulated with extruded polystyrene foam boards and the other was uninsulated. The inside room temperatures of the two huts were kept the same by means of air conditioners. The thermal behavior was measured over a period of six months. The external and internal surface temperatures of the west and east walls were measured, as well as the roof membrane temperature. The thermal insulation resulted in substantial reductions in heat flow through the walls and roof. The inside surface temperatures of the walls and the roof membrane temperature were very close to the inside design room temperature. The thermal insulation proved to be an effective measure for reduction of heat transmission through walls and roofs of buildings. In addition the insulation protected the roof from extreme temperature cycling, which was observed in the uninsulated building. The insulated hut showed far fewer and smaller cracks than the uninsulated hut, which contributes to longer building life.

Longevity of Alfalfa Seed1

Two hundred twenty‐eight lots of alfalfa (Medicago spp.) seed, ranging in age from 23 to 70 years (stored between 1906 and 1953) were tested for germination. A seed lot represented a plant introduction or open‐pollinated seed from a single plant. The seed had been stored in unheated and uninsulated buildings at Belle Fourche, S. D., and Mandan. N. D. One M. falcata L. seed lot germinated 27% awter 68 years and a second lot germinated 48% after 66 years of storage. For M. sativa L., one seed lot germinated 7% after 70 years and a second lot germinated 30% after 62 years of storage. Medicago falcata, in most instances, retained seed viability longer than did M. sativa. Significant variation between seed lots of the same species harvested the same year suggests that seed longevity may be genetically controlled. This hypothesis is supported by wide differences in seed longevity of M. sativa and M. falcata. When germination percentage was regressed on years of storage, a correlation coefficient of —0.95 and a linear regression coefficient of —2.23 were found for M. sativa and some of its hybrids. Coefficients were significant at a >0.0001 probability level. Every year of storage between 30 to 70 years presupposed a 2.23% decline in seed germination.

Effective temperature as a measure of environmental conditions for pigs

1. Three experiments confirmed the view that losses, poor weight gains and low food consumption were always problems among pigs reared in an open pen in a large uninsulated building in comparison with the better results for pigs reared in wooden ark huts. Pigs in an ark hut with an outdoor run did better than those in one with an indoor run.2. The effective temperature of the different types of housing was estimated. The differences found were not large but the environment which produced the best pigs had the highest effective temperature.3. The provision of an insulated, dry floor to sleep on made it possible to rear good pigs in a pen where before they had failed. Woollen jackets did not provide sufficient insulation to affect the growth or health of pigs in a hut or pen.