• The Journal of Engineering Geology
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• v.19 no.4
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• pp.493-499
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• 2009

Recently, the construction of Concrete Faced Rockfill Dam (CFRD) is increasing because rock material resources are plenty in Korea. Bedding zone in the CFRD is necessary enough bearing capacity to support the concrete face slab uniformly and enough impermeability to prevent the loss of fine soils in case of leakage from the concrete slab face. Therefore, cut-off the water leakage in bedding zone securely is the key factor influencing the safety of CFRD. Tested materials satisfied with the specification of particle size distribution at the Bedding Zone area are chosen for conducting permeability tests, which are done to evaluate the property of cut off the materials. Based on the test results, the effects of cut off the materials are investigated by considering the coefficient of permeability, the soil particle distribution, and the dry unit weight. Especially, the relationships between coefficient of permeability with effective size(D10), dry unit weight, and weight passing percent the No.4 sieve are suggested, and also the variation of coefficient of permeability with time are proposed.

• Asian Journal of Atmospheric Environment
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• v.4 no.1
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• pp.33-41
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• 2010

Because ammonia from livestock production may substantially contribute to environmental pollution, emissions from all possible sources (housing systems, manure storage, manure application, outside grazing) should be reduced. The purpose of this study was to investigate the effect of different bedding materials on ammonia emissions in a cow house. By applying a combination of four treatment types: treatment $1-T_1$ (sawdust (50%)+sawdust pellets (50%)), treatment $2-T_2$ (sawdust (50%)+corn stalk pellets (50%)), treatment $3-T_3$ (sawdust (100%)), and treatment $4-T_4$ (sawdust (50%)+palm kernel meal pellets(50%)) as bedding materials in a cow house, the effects of such treatments on ammonia flux were assessed in approximately one month. The magnitude of ammonia emissions (mg $m^{-2}\;min^{-1}$) varied in the following order: $T_1$(2.226), $T_4$(2.052), $T_2$(1.845), and $T_3$(1.712). The patterns of pH had a decreasing trend for all bedding treatments during the experiment, and there was no significant relationship with ammonia flux. The results reveal that the most important factor influencing ammonia emissions is the physical structure of the bedding types.

• Asian-Australasian Journal of Animal Sciences
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• v.33 no.11
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• pp.1858-1865
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• 2020

Objective: The microbiota of dairy cow milk varies with the season, and this accounts in part for the seasonal variation in mastitis-causing bacteria and milk spoilage. The microbiota of the cowshed may be the most important factor because the teats of a dairy cow contact bedding material when the cow is resting. The objectives of the present study were to determine whether the microbiota of the milk and the cowshed vary between seasons, and to elucidate the relationship between the microbiota. Methods: We used 16S rRNA gene amplicon sequencing to investigate the microbiota of milk, feces, bedding, and airborne dust collected at a dairy farm during summer and winter. Results: The seasonal differences in the milk yield and milk composition were marginal. The fecal microbiota was stable across the two seasons. Many bacterial taxa of the bedding and airborne dust microbiota exhibited distinctive seasonal variation. In the milk microbiota, the abundances of Staphylococcaceae, Bacillaceae, Streptococcaceae, Microbacteriaceae, and Micrococcaceae were affected by the seasons; however, only Micrococcaceae had the same seasonal variation pattern as the bedding and airborne dust microbiota. Nevertheless, canonical analysis of principle coordinates revealed a distinctive group comprising the milk, bedding, and airborne dust microbiota. Conclusion: Although the milk microbiota is related to the bedding and airborne dust microbiota, the relationship may not account for the seasonal variation in the milk microbiota. Some major bacterial families stably found in the bedding and airborne dust microbiota, e.g., Staphylococcaceae, Moraxellaceae, Ruminococcaceae, and Bacteroidaceae, may have greater influences than those that varied between seasons.

• Journal of the Korean Geosynthetics Society
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• v.6 no.2
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• pp.9-15
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• 2007

Bedding zone in CRFD (Concrete Faced Rockfill Dam) requires bearing capacity to support the concrete face slab uniformly. Also, shear strength which is a key factor in slope stability and impermeability which is to prevent a loss of soils in case of leakage of concrete slab face are needed. In this study, trial prototype construction for bedding zone in CRFD was performed to investigate the compaction characteristics of bedding zone according to the frequency of compaction, water contents and so on. As a results of series of field test, the compaction characteristics of bedding zone in CRFD was affected considerably by the depth of compaction layer and frequency of compaction.

• Journal of the Korea institute for structural maintenance and inspection
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• v.11 no.6
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• pp.121-130
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• 2007

In this paper, large scale experimental model tests were performed to investigate the distribution of earth pressure acting on embedded rigid pipes having different bedding conditions. For these tests, very light weighted EPS blocks were installed at top and bottom of the rigid pipe and Jumunjin Standard Sand was used as a ground material. As results of model tests, for the case of no bedding on the pipe, the measured pressure at the bottom of the pipe was $4.96_{tf/m^2}$ whereas they were in the range of $1.87{\sim}4.96_{tf/m^2}$ in the case of EPS beddings being installed at the top and the bottom of the pipe. Therefore, for the case of EPS bedding being installed, the ratio of reduced pressures acting on the pipe, compared with the case of no EPS beddings, were in the rage of 16~62%. As a result of parametric test with changing the locations of EPS bedding, the trend of reducing the stress acting on the pipe was in the order of bottom bedding, top bedding, and top and bottom bedding. Effect of bedding positions on the reduced magnitude of acting pressure on the pipe was more significant in the case of top bedding than in the case of the bottom bedding.

• Textile Coloration and Finishing
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• v.29 no.4
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• pp.231-238
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• 2017

There are many kinds of elements and processes for the development of high quality bedding products like fiber, high-temperature heat treatment, dyeing process, tenter drying with softening agent and multiple final finishing. Especially we examined the mechanical characteristic properties of fabrics according to different yarn types. The critical physical properties of the yarn consisting the pile knitted fabrics were obtained for the development of the hi-grade bedding items. The material property and the exhaustion behaviour of the developed pile knitted fabrics composing of different yarns were measured and observed. The physical properties of the developed fabric were evaluated through the material property analysis of the yarn, the physical nature of the pile knitted fabrics and the data of the exhaustion performance; tensile strength, tensile elongation, tearing strength, cross section of yarn types, dyeing properties etc. And then high-class of bedding items were knitted using the double raschel machine to make the pile knitted fabrics.

• Journal of Animal Science and Technology
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• v.65 no.2
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• pp.377-386
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• 2023

The effect of different commercially available bedding materials on the growth performance and carcass characteristics of ducks for 42 days was investigated. 336 one-day-old White-Pekin ducklings (60.48 ± 0.16 g) were randomly allocated into 24-floor pens with one of the three beddings namely i) coco peat, ii) rice husks, or iii) sawdust. 14 ducklings per pen and 8 replicate pens per bedding material were used. Birds were fed a starter diet from days 1-21 and a grower diet from days 22-42. Weekly growth performance evaluation was conducted for the average body weight, weight gains, daily feed intake, and feed conversion efficiency. One bird per pen was sacrificed on day 42 for the evaluation of carcass characteristics including the carcass, breast, and leg muscle percentages. Breast and leg muscle samples were then collected and analyzed for their proximate and pH values. Higher body weights (p < 0.05) were noticed with rice husks on day 42 only. Improved daily gains (p < 0.05) were also noticed for birds raised with rice husks over the entire period (days 1-42). Concerning feed intake, higher values (p < 0.05) were similarly noted with rice husks for the grower phase (days 22-42), and the entire experimental period (days 1-42). Marginally improved feed intake values were also noted with the use of rice husks as the bedding materials on day 42 (p = 0.092). Improved feed efficiency (p < 0.05) was noticed with rice husks on day 35, the grower period, and the entire 42-day period. However, no significant differences were noticed for most of the carcass characteristics that were evaluated. Nevertheless, higher (p < 0.05) pH values for the breast muscle were noticed with the use of coco peat and sawdust as the bedding. Conclusively, the bedding type could have a significant impact on the growth performance of ducks without adverse effects on carcass characteristics. The use of rice husks as bedding might be advantageous and is therefore recommended.

• Asian-Australasian Journal of Animal Sciences
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• v.29 no.3
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• pp.444-454
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• 2016

This study was designed to examine the characteristics of sawdust and cocopeat bedding materials, including physicochemical properties (Exp. I) and on-farm trial (Exp. II). In Exp. I, the proportion of particle size was in the order of sawdust>cocopeat India>cocopeat Vietnam (p<0.05), and cocopeat contained higher proportion of small particles ($250{\mu}m$+below $250{\mu}m$) than sawdust, causing a dust production problem. Bulk density was cocopeat India>cocopeat Vietnam>sawdust (p<0.05), thus cocopeat treatments showed 4.4 times higher bedding cost than sawdust. The water absorption rates were 702.0% in cocopeat India, 678.3% in cocopeat Vietnam, and 444.0% in sawdust, showing cocopeat had approximately 1.5 times higher water absorption rate than sawdust. Moisture evaporation rates after 12 h of air blowing (2.00 m/s) were higher (p<0.05) in cocopeat Vietnam (80.4%) than sawdust (71.2%) and cocopeat India (72.8%). In vitro ammonia emissions were higher (p<0.05) in sawdust ($2.71mg/m^2/h$) than cocopeat India ($1.59mg/m^2/h$) and Vietnam ($1.22mg/m^2/h$), and total ammonia emissions were higher (p<0.05) in sawdust ($37.02mg/m^2$) than cocopeat India ($22.51mg/m^2$) and Vietnam ($13.60mg/m^2$). In Exp. II, an on-farm trial was conducted with 48 Hanwoo cattle in 16 pens using the same bedding materials as in Exp. I, with fan (blowing 2.00 m/s) and no fan treatments, and feed bunk side (FB) and water supply side (WS) within a pen (4.5 m, $width{\times}9.0m$, length). Beddings were replaced with fresh bedding materials when moisture concentrations were over 65%. No interactions among treatments were detected for moisture concentration and increment rates, and ammonia concentrations, but a significant effect was observed (p<0.01) for each of the treatments. Both concentrations and increment rate of moisture were higher (p<0.01) in the beddings without fan than with fan. Moisture concentrations and increment rate within a pen were also higher (p<0.01) in FB than WS. Thus, the whole no-fan-FB and sawdust-fan-FB were replaced with fresh bedding material between 4 to 5 experimental weeks. The ammonia concentrations and pH of beddings were not significantly different among treatments. Therefore, using cocopeat bedding with a blowing fan can extend twice the bedding utilization period, and WS within a pen showed twice the bedding-life compared to FB. Despite the outstanding characteristics of cocopeat compared with sawdust, using cocopeat as an alternative for sawdust bedding is not recommended for cattle management, considering it has 4.4 times higher bedding cost and a dust production problem.

• Asian-Australasian Journal of Animal Sciences
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• v.28 no.1
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• pp.143-150
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• 2015

The objective of this study was to evaluate the effects of different litter mixture compositions on bedding system temperature, pH and volatile fatty acid and ammonia-N ($NH_3$-N) content, and the serum physico-chemical parameters and growth indices of calves. Thirty-two Limousin calves ($280{\pm}20kg$) were randomly assigned to four groups (n = 8 for each group) according to the bedding system used: i) control with soil only (CTR); ii) mixture with 50% paddy hulls (PH), 30% saw dusts (SD), 10% peat moss (PM) and 10% corn cobs (CC) (TRT1); iii) mixture with 15% PH, 15% SD, 10% PM, 40% CC, and 20% corn stover (CS) (TRT2); iv) mixture with 30% PH, 10% PM, 40% CC, and 20% CS (TRT3). The litter material combinations of different treatments were based on the cost of bedding system materials in China. The cost of four treatments from low to high: Control$NH_3$-N level (271.83 to 894.72 mg/kg) was lowest for TRT1 (p<0.0001) and highest for TRT2 (p<0.0001). The acetate, propionate and butyrate levels were highest for the control group (p<0.0001). In all the groups, the pH value (6.90 to 9.09) increased at the beginning and later remained stable at below 9.09. The temperature of deep litter increased at the first week and reached the maximum ($42.1^{\circ}C$) on day 38. 3,5,3'-Triiodothyronine ($T_3$) levels in the TRT1 group animals (p<0.0001) were lower than those in the control and TRT2 animals. 3,5,3',5'-Tetraiodothyronine ($T_4$) in the TRT1 group (p = 0.006) was lower than that in the other treatment groups. Cortisol (COR) in the control and TRT1 group was lower (p<0.0001) than that in the TRT2 and TRT3 groups. Corticosterone (CORt) in the control group was higher (p<0.0001) than that in the treatment groups. The findings indicate that the deep litter bedding systems provided better conditions for animal health and growth performance compared with the control system. Furthermore, the litter composition of TRT1 was found to be optimal among the three treatment groups.

• Korean Journal of Poultry Science
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• v.45 no.4
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• pp.273-283
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• 2018

Two diet energy levels (high or low) and two bedding material (rice husk or saw dust) treatments were designed for either male or female slow-growing Korean meat-type chicken (Hanhyop 3) to make totally eight treatments for 11~75 d feeding trial. Body weight gain (BWG) were influenced by energy levels, sex of bird and bedding material type. There were interaction effect among those three factors. Feed intakes (FI) by male bird during each and overall periods were higher than those by female. Diet energy levels and bedding material affected the FI only during final 56~75 d period, of which FI of high energy diet was higher in male whereas that of low energy diet was higher in female. Although feed conversion ratio (FCR) was improved by high energy diet, the better FCR has dissipated during 41~75 d, when the most of overall BWG were achieved. Apparent total tract retention (ATTR) of nutrients were higher in male than those in female birds with exception on fat ATTR. Fat ATTR was improved when fed low energy diet regardless of the sex of birds. Both energy levels and sex of bird influenced the color of breast. Thiobarbituric acid reactive substances (TBARS) value of female thigh was higher than that of male. Levels of moisture and P in female thigh were lower although level of fat in female breast was higher than those in male, respectively. This study showed that diet energy levels for Hanhyop 3 chicken, especially during 41~75 d, should be differently formulated between male and female bird.