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451.
We investigated the effects of wood kraft pulp (KP) feeding on feed digestibility and rumen fermentation of Japanese Black (JB) steer in the middle fattening stage. The feeding experiment was carried out a replicated 3 × 3 Latin square design using six JB steers (16.2 ± 0.8 months of age). Steers were fed rice straw and three concentrated feeds: commercial formula feed (control), formula feed containing 7.5% KP on a dry matter (DM) basis (7.5% KP), and formula feed containing 15% KP on a DM basis (15% KP). Feed digestibility and rumen fermentation parameters were recorded for 3 days during the measurement period, after an adaptation phase of 11 days. There was no significant difference in DM intake per day among diets. A slightly higher digestibility of neutral detergent fiber was observed in steers fed 15% KP, compared with those fed other diets (P = 0.059). The butyric acid ratio in rumen fluid was higher in steers fed KP diets than in steers fed control (P = 0.083). The average ruminal pH was unaffected by KP diets. This study suggests that replacing 15% of concentrated feed with KP has little effect on feed digestibility and rumen fermentation in JB fattening steer.  相似文献   
452.
Postpartum metritis is a common problem in many animal species. In equine medicine, sequelae of postpartum metritis vary from delay in uterine involution to development of systemic acute metritis (SAM), toxemia, and laminitis. Heavy draft mares potentially have higher risk of suffering from SAM than light breed mares. Postpartum fever (PF) mostly appears as a sign of SAM. The purpose of this study is to analyze the factors affecting the incidence of PF in 158 foalings from 62 heavy draft mares by multiple logistic regressions. The objective variable was the incidence of PF, and the explanatory variables were year foaled, month foaled, age of mare, breed of mare (crossbred heavy draft horse vs. Percheron), gestation length, foaling difficulty (easy delivery vs. dystocia), retained fetal membranes, stillbirth, and sex of offspring. Twenty-four out of 158 mares were diagnosed with PF. Stepwise regression analysis showed that breed of dams and foaling difficulty were significant risk factors for PF. Percheron mares had higher risk than crossbred mares (odds ratio: 3.4). Dystocia had higher risk than easy delivery (odds ratio: 3.3). Percheron mares had higher incidence of PF than crossbred mares even in the cases of easy delivery. Risks for damage and contamination of birth canal will be increased especially if the fetal delivery needs assistance. The results of this study suggest that it is necessary to consider the foaling difficulty and the breed of dams for earlier detection of PF in peripartum heavy draft mares.  相似文献   
453.
Forest certification for community-based forest management was designed to strengthen an area’s forestry functions while simultaneously alleviating poverty by developing the existing community forest. It is fundamental for forest certification to maintain the economic benefits for certified local sellers and balance conservation goals with increasing local incomes. This study explores how FSC certification of a community-based forest enterprise in Southeast Sulawesi in Indonesia could improve effectively field situations of community forest management and strengthen local peoples’ financial benefits and social perceptions towards conserving forests. FSC group certification was introduced in the area of teak community forest of several villages in 2005. Because of local strong interest in group certification, the size of certified forests, the number of group certification members and the amount of certified wood harvested gradually increased. The support of a local NGO and an international NGO contributed towards successful establishment of group certification and establishment of a small-scale forestry enterprise producing certified wood in a sustainable manner. These NGOs played important roles in establishing strong relationships between producers and consumers, strengthening local forest management institutions, and promising social and economic benefits to the local people.  相似文献   
454.
普通小麦白粉病成株抗性的QTL分析   总被引:6,自引:1,他引:6  
以抗白粉病的日本小麦品种Fukuho-komugi和以色列小麦Oligoculm杂交F1的DH(doubled haploid)群体107个系为材料,利用313个SSR标记和37个RFLP标记,对Fukuho-komugi和Oligoculm的白粉病成株抗性进行QTL分析。试验材料于2003-2004年度种植在北京、2003-2004和2004-2005年度种植在安阳,调查白粉病发病情况。构建了由350个位点组成的遗传连锁图,覆盖小麦21个连锁群,全长3 101 cM。采用复合区间作图法进行白粉病成株抗性QTL分析,在1A、2B、4B和7D上发现4个抗白粉病QTL,分别解释13.6%、6.6%、8.9%和12.7%的表型变异。抗白粉病基因及其紧密连锁分子标记的发掘,将为小麦抗白粉病育种的分子标记辅助选择提供理论和技术支持。  相似文献   
455.
Worldwide, only a few “fatty” pig breeds exist with different and/or regional utilization. Using the Hungarian Mangalica, which almost went extinct in Europe and the Lao Moo Lat pig, which still has a large population in South-East Asia as exemples, we wanted to demonstrate that indigenous (fatty) pig breeds may represent both national value and tremendous economic potential. Since these less prolific and less productive breeds cannot contribute to mass production, new market roles and methods should be established for them in the premium segment of pork trading. Thus their preservation and propagation needs the comprehensive collaboration of commercial, governmental actors and researchers. Briefly summarizing the history, we report the current results of reproductive physiology research. The commercial renaissance of Mangalica pigs is indebted to the enthusiastic efforts of basic scientists, pig breeding experts and dedicated Mangalica producers. Scientific achievements were applied to practical breeding and production of delicious pork and processed products, which ultimately made the economic success in the Mangalica sector possible. Both, research on and utilization of endangered (pig) breeds maintain not only breed diversities, but also may improve the livelihood of farmers worldwide.  相似文献   
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457.
Journal of General Plant Pathology - Three nitrate-nonutilizing (nit) mutants of a soil-borne fungus, Diaporthe destruens, pathogen of foot rot of sweet potato, were generated with a...  相似文献   
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460.
A new coupled model (PCPF–SWMS) was developed for simulating fate and behavior of pollutant in paddy water and paddy soil. The model coupled the PCPF-1, a lumped model simulating pesticide concentrations in paddy water and 1 cm-surface sediment compartment, and the SWMS-2D, a finite element numerical model solving Richard's and advection-dispersion equations for solute transport in soil compartment. The coupling involved improvements on interactions of the water flow and the concentration the pollutant of at the soil interface between both compartments. The monitoring data collected from experimental plots in Tsukuba, Japan in 1998 and 1999 were used to parameterise and calibrate hydraulic functioning, hydrodynamic and hydrodispersive parameters of the paddy soil. The analysis on the hydraulic functioning of paddy soil revealed that the hard pan layer was the key factor controlling percolation rate and tracer transport. Matric potential and tracer monitoring highlighted the evolution of saturated hydraulic conductivity (K S) of hard pan layer during the crop season. K S slightly decreased after puddling by clay clogging and strongly increased after mid term drainage by drying cracks. The model was able to calculate residential time in every soil layers. Residential time of tracer in top saturated layers was evaluated to be less than 40 days. It took 60 days to reach the unsaturated layers below hardpan layer.  相似文献   
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