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《The Journal of Applied Poultry Research》2018,27(1):59-64
An experiment was conducted to examine the suitability of chopped palm leaves to utilize as a bedding material, compared to wood shavings or wheat straw, on growth performance, immune response, and air quality for broiler production. Three bedding materials were used: wood shavings, chopped palm leaves, and wheat straw. A total of 3,240 one-day-old broiler chicks (Ross 308) was randomly distributed into 3 litter groups (1,080 birds each). Each group had 6 replicate pens (180 birds/pen). All birds were kept under similar environmental conditions, except for bedding material. The obtained results revealed that the growth performance and total mortality rate were not significantly affected by bedding material type. However, using chopped palm leaves as bedding material significantly reduced (P < 0.05) ammonia emission compared to wood shavings and wheat straw (4.1, 7.3 and 8.4 ppm, respectively). A similar trend was observed for settled dust concentration (4.0, 10.3, and 5.9 g/m2, respectively). Moreover, an improvement in cell-mediated immunity was observed in boilers kept on chopped palm leaves. Carcass characteristics were not significantly affected by bedding material. It was concluded that chopped palm leaves are a good alternative bedding material to wood shavings and wheat straw in commercial broiler production. 相似文献
955.
Computed tomographic description of the highly variable imaging features of equine oromaxillary sinus and oronasal fistulae
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Oronasal and oromaxillary sinus fistulae are well‐documented complications following removal or loss of a maxillary cheek tooth. Diagnosis is currently based on a combination of oral examination, videoendoscopy, radiography, and computed tomography (CT). The objective of this retrospective, case series study was to describe the CT characteristics of confirmed oronasal and oromaxillary sinus fistulae in a group of horses. Inclusion criteria were a head CT acquired at the authors’ hospital during the period of 2012–2017, a CT diagnosis of oronasal or oromaxillary sinus fistulae, and a confirmed diagnosis based on a method other than CT. Signalment, clinical findings, oral examination findings, presence of a confirmed fistula, and method for confirmation of the diagnosis were recorded. A veterinary radiologist reviewed CT studies for all included horses and recorded characteristics of the fistulae. Seventeen horses were sampled. Fourteen oromaxillary sinus fistulae and three oronasal fistulae were identified. All fistulae appeared as variably sized focal defects in the alveolar bone. Defects frequently contained a linear tract of heterogeneous material interspersed with gas bubbles, considered consistent with food. Computed tomographic attenuation of the material (Hounsfield units, HU) varied widely within and between cases. In 16 of 17 cases, there was evidence of concurrent dental disease in addition to the fistulae. Although the gold standard diagnostic test remains identification of feed material within the sinus or nasal passages, findings from the current study support the use of CT as an adjunctive diagnostic test for assessing the extent of involvement and presurgical planning. 相似文献
956.
Bacteriological evaluation of composted manure solids prepared from anaerobic digested slurry for hygienic recycled bedding materials for dairy cows
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Eiryu Okamoto Hiroki Miyanishi Akinobu Nakamura Tomoyuki Kobayashi Norihiko Kobayashi Yoshinori Terawaki Hajime Nagahata 《Animal Science Journal》2018,89(4):727-732
Changes in mastitis‐causing pathogens, pH and water content in composted manure solids (CMS) prepared from digested slurry were evaluated during turning at 2‐day intervals for 8 days (C1–C4). The numbers of streptococci, coagulase‐negative staphylococci and coliforms were 2.6 × 101, 1.7 × 102 and 1.0 × 101 colony‐forming units (cfu)/g in CMS (C4) (summer), and these counts were markedly lower (P < 0.05) than those in CMS (C0 and C1). The bacterial counts ranged from 101 to 1.7 × 102 cfu/g in CMS (C4) (summer) and were within approved levels, <1 × 106 cfu/g, indicating a minimal mastitis risk. The temperatures in CMS (C1–C4) increased to 63°C–74°C in summer and 67°C–70°C in winter. The mean pH values in CMS (C0–C4) were 9.2 in summer and 8.7 in winter, and water contents ranged from 61.7% to 69.6% in summer and 73.2% to 66.2% in winter. The significant decrease of pathogenic bacteria in CMS appears to be closely related to temperature >63°C for 8 days, pH 8.7–9.2, and water content 62% to 73%. This study demonstrates that prepared CMS has value as a recycled material with the potential to alleviate udder health issues in dairy cows. 相似文献
957.
Su Zhifeng Yang Wenping Yang Zhenping Du Tianqing Hao Jiaomin Sun Min Gao Zhiqiang 《棉花学报》2015,27(5):435-444
为探求生土地当年最佳施肥方式,快速提高棉花地上部生产力并改良根干物质质量垂直分布,试验连续2年以黄土母质生土为供试土壤,采用根管土柱法,研究不同肥料(N,P,NPK,有机肥,不施肥对照(CK))、不同施肥深度(0~20 cm,40~60 cm,80~100 cm土层)对棉花(Gossypium hirsutum)茎叶干物质质量、棉铃干物质质量及根干物质质量垂直分布的影响。结果表明,所有处理中,以有机肥深施40~60 cm处理的茎叶和棉铃的干物质质量最大,其次为NPK肥深施40~60 cm处理,二者差异显著(P0.05);以含P肥深施40~60 cm处理的根干物质质量较大,且40 cm以下根层的分布比例较大;所有处理均以0~20 cm层的根分布比例最大,约占0~100 cm总根干物质质量的40%~80%。总的来看,当年生土地棉花冠 ̄根系统的最佳肥料运筹是有机肥深施40~60 cm。 相似文献
958.
Foliar sprays of pesticides are frequently used to control two-spotted mites on rose flowers, but these also destroy predatory mites and pose a high risk of contamination for humans and the environment. Using a novel approach to avoid spray applications on rose plants, modified acaricide-treated string curtains were adapted to control the pest. Two main aims of this study were: (i) to identify the lethal concentration of string curtains treated with propargite, dicofol, flufenoxuron, acrinathrin or tau-fluvalinate (τ-fluvalinate) on Tetranychus urticae, and (ii) to test the design (feasibility) and efficiency of the string curtains to trap the phytophagous mites on the plants during their circadian migration. Bioassay results in the lab confirmed T. urticae circadian migration, toxicity of the five kinds of treated string curtains and a concentration-dependent repellent effect of each chemical on T. urticae females. Of the two products tested in the field, dicofol was more effective than acrinathrin in controlling T. urticae compared to an acaricidal spray of the same products. The effect of acaricide-treated string curtain use on Phytoseiulus persimilis did not differ significantly from the control. The string curtain technique proved to be effective, but because of some biotic and abiotic constraints and the low economic threshold of mites, even for the commercialized high canopy stem roses, the present device could be more appropriate for another horticultural crop, e.g. tomato. 相似文献
959.
在对侗寨民居环境的调研中,侗族人们运用自然材料青石板搭建台阶,其尺度感的把握,技巧运用及空间布局,很好地符合使用者的需求,利用地势的高差合理地将台阶铺设融于自然之中,使台阶的功能与形式自然、纯朴地表现出来。经过代代发展侗族人们铸就了对自然材料的领悟和运用及对材料之美的理解和尊重。 相似文献
960.
随着我国建筑业的发展,建筑工程的安全性与耐久性已成为人们重视的课题;未来建筑的发展方向一定是更高,更坚固,使用年限更长、更舒适,随之而来的是需要探讨新材料研发、施工温度控制及管理措施等一系列问题。 相似文献