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931.
932.
933.
Raffaele Spinelli Natascia Magagnotti Carla Nati 《European Journal of Forest Research》2011,130(5):737-744
In Italy, poplar plantations represent an important source of wood products, and especially of high-quality veneer logs. These
plantations offer favourable conditions to the introduction of forest mechanisation, and especially easy access and industrial
management. However, owners fear that mechanised log-making may cause value losses, due to poor length measurement, log surface
damage and improper grading. This study compared the performance of manual and mechanised log-making on ten commercial operations,
in order to determine the occurrence and the severity of possible value losses due to product degrade. The study found that
length measurement errors are smaller for mechanised processing, while the frequency and severity of log surface damage are
the same for both treatments. In three cases out of five, mechanised log-making extracted the same value from the stems as
manual log-making: in the remaining two, differences were very small and went opposite directions. Significant differences
were found between operators, stressing the importance of operator skills and motivation. In fact, the log-making specifications
and the pricing structure applied to poplar processing are relatively simple and are unlikely to challenge the ability of
personnel and equipment. At present, most Italian poplar growers are unaware of the potential offered by modern technology,
whose intelligent use would boost value recovery and decrease harvesting cost. Significant benefits may derive from the introduction
of optimised bucking, which may help shifting to a more articulated and rewarding product strategy. 相似文献
934.
Mersha Chanie Tamiru Negash Samuel Bekele Tilahun 《Tropical animal health and production》2009,41(7):1309-1317
Commercial poultry production is one of the flourishing ventures of animal production in Ethiopia. It has been providing to
the demands of proteins at least to the urban population, though concurrent health constraints are hampering its intended
potential. This study reports the influence of infectious diseases in commercial broiler farms in central Ethiopia. In this
study, clinical signs, gross lesions, laboratory tests (serology, bacterial culture, histopathology and parasitology) and
farm management data were used to identify major causes of outbreaks in an age specific manner in broiler chickens in three
poultry farms in Debre Zeit, Central Ethiopia. The outbreaks detected in the farms were due to mycoplasmosis, salmonellosis,
colibacillosis, coccidiosis and infectious bursal disease. It is observed that the occurrence of concurrent diseases in the
farms significantly affects the productivity and health status of broilers. The risk factors that predispose birds to the
various infections in the different farms studied were also recorded. In addition, recommendations were also provided. 相似文献
935.
研究日粮中添加不同水平的红花油对生长育肥猪生长性能和胴体品质的影响.日粮中添加红花油水平分别为0,0.4%,0.6%,0.8%和1%.结果表明:添加红花油的各试验组的平均日增重、粗蛋白、粗脂肪、粗纤维等消化率显著提高(P〈0.05),饲料利用率得到改善;各试验组猪的屠宰率和瘦肉率显著高于试验组1,眼肌面积、脂肪酸含量也比试验组1得到提高,降低了胆固醇含量,改善了猪肉品质. 相似文献
936.
Penultimate and last instar larvae of the common citrus swallowtail butterfly, Papilio demoleus L. (Papilionidae: Lepidoptera), were treated with different doses of a novel juvenoid, diofenolan. Several deformities were
observed as a result of topical administration of diofenolan which include delay in larval–larval and larval–pupal ecdysis,
ecdysial failure, mortality, severe reduction in pupation, deformed pupae and complete inhibition of adult emergence. The
juvenoid diofenolan severely hampers the normal growth, development and metamorphosis of P. demoleus and can be incorporated into integrated pest management programs for successful control of this important pest of citrus
all over the world. 相似文献
937.
Alate viviparous females of Wahlgreniella nervata (Gillette) were found on a Damask rose (Rosa damascena Mill.) plantation in Isparta Province, Turkey. The aphid is recorded for the first time from Turkey. Besides, Damask rose
is a new host for this species. Brief information about this aphid including a key to the alate females of aphid species known
to infest Damask rose in Turkey is provided. 相似文献
938.
Francis Mbuza Rosine Manishimwe Janvier Mahoro Thomas Simbankabo Kizito Nishimwe 《Tropical animal health and production》2017,49(1):71-77
A study was conducted on 37 randomly selected broiler poultry farmers in Rwanda to characterize the production system using pre-tested semi-structured questionnaires. The data were processed in SPSS and presented as means, percentages and ranges in tables and text. All respondents kept Cobb breed and young stock was mainly (73 %) imported from abroad. The majority of respondents were males (68 %) and most farmers had attended only primary level of education (40.5 %). Most of the farms were in the peri-urban (48.6 %) and urban (37.8 %) areas and hired male youth (62.2 %) mainly aged 19–35 years. The majority of respondents (68 %) kept less than 500 birds per batch. Recordkeeping was well practiced (91.9 %) and (62.6 %) had permanent poultry houses and all farmers used deep litter system. Purchased feedstuffs were reportedly (92 %) mixed at farm level as the main feed resource. Maize bran was reported (97.06 %) the main, basal feedstuff. The mortality rates of chick and growers were 12.3 and 9.4 %, respectively. The slaughter age was reportedly 60 days with an average dressing percentage of 75.67 %. The main challenges reported were scarcity and unaffordability of quality feeds (59.5 %), lack of market access (45 %) and lack of credit (21 %). The farmers had various views on improving broiler production in Rwanda ranging from establishing feed processing industries 62.2 %, improving marketing facilities 35.1 %, increasing availability of day-old chick and access credit 27 %, to intensification of farmer training 16.2 %. 相似文献
939.
仿刺参及养殖环境中溶藻弧菌和灿烂弧菌的PCR快速检测 总被引:3,自引:0,他引:3
溶藻弧菌和灿烂弧菌是水产养殖中常见的致病菌,给水产动物的养殖带来巨大的损失,建立一种简便、快速、有效的检测方法十分必要。根据溶藻弧菌和灿烂弧菌gyrB基因序列的保守区序列分别设计引物,对9株溶藻弧菌和6株灿烂弧菌进行了PCR扩增。结果表明两对引物能特异地检测溶藻弧菌和灿烂弧菌,而与其他细菌没有交叉反应;检测溶藻弧菌的每个PCR反应的敏感度为0.13 pg的DNA和103 cfu/mL细菌,检测灿烂弧菌的每个PCR反应的敏感度为0.34 pg的DNA和103 cfu/mL细菌。该PCR检测方法具有特异性好、灵敏度高的特点,可用于对感染溶藻弧菌和灿烂弧菌的仿刺参及其养殖水体中的细菌性病原进行快速检测。 相似文献
940.