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41.
The effects of three non‐nutrient additives on nonspecific immunity and growth of juvenile turbot (Scophthalmus maximus L.) were studied in this feeding experiment. The five treatments are basal diet alone, basal diets containing three different additives [0.4 g kg?1 of xylo‐oligosaccharides (XOS), 1.3 g kg ?1 of yeast cell wall and 0.8 g kg ?1 of bile acids] individually or in combination. Two hundred and twenty‐five turbots (average initial weight 151.3 ± 11.3 g) were randomly allotted in five treatments with three replicates within each treatment in a 72‐day period. Comparing with basal diet group, activities of C3, C4, phagocyte, lysozyme, specific growth rate and feed conversion rate in yeast cell wall, XOS and the combined groups was enhanced significantly (P < 0.05); however, these parameters in bile acid groups were increased slightly (P > 0.05) except for phagocyte (P < 0.05); superoxide dismutase activity in additive groups was not significantly increased (P > 0.05) except for the combined group (P < 0.05). In conclusion, supplementation of yeast cell wall and XOS enhanced the nonspecific immunity of juvenile turbot. Synergistic or additive effect of the three additives was not observed. 相似文献
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43.
【目的】牛只体重数据是衡量牛体健康生长发育的重要指标,定期对牛只称重对实施精细化养殖有重要意义。【方法】采用带围栏的地磅称重、月龄推算、体尺估算测量以及采用保定架等方法对肉牛进行静态称重。【结果】可以实现肉牛全程无障碍通过,在肉牛自然行走状态下监测出肉牛体重信息,有效避免了肉牛产生应激反应;称重效率高,系统锁定肉牛有效体重数据在2~4 s。平均每头牛从进入通道排队到称重结束,时间在10 s之内。肉牛速度较快通过称重平台时,误差在0.5%以下;肉牛在行走—停顿运动状态和平稳行走运动状态下,误差在0.2%以下。【结论】肉牛无应激自动化动态称重系统,主要由主体机械结构框架、RFID无线射频识别系统、供电系统、称重系统、数据传输5部分组成。 相似文献
44.
Turi K Aarnes John AE Hubbell Phillip Lerche Richard M Bednarski 《Veterinary anaesthesia and analgesia》2014,41(2):174-185
ObjectiveTo determine the level of agreement between an oscillometric (O-NIBP) and an invasive method (IBP) of monitoring arterial blood pressure (ABP) in anesthetized sheep, goats, and cattle.Study designProspective clinical study.AnimalsTwenty sheep and goats, 20 cattle weighing <150 kg body weight, and 20 cattle weighing >150 kg body weight.MethodsAnimals were anesthetized and systolic ABP (SABP), mean ABP (MABP), and diastolic ABP (DABP) were measured using IBP and O-NIBP. Differences between IBP and O-NIBP, and 95% limits of agreement (LOA) between SABP, MABP, and DABP values were assessed by the Bland–Altman method.ResultsMean difference ± standard deviation (range) between SABP, DABP, and MABP measurements in sheep and goats was 0 ± 16 (-57 to 38) mmHg, 13 ± 16 (-37 to 70) mmHg, and 8 ± 13 (-34 to 54) mmHg, respectively. Mean difference between SABP, DABP, and MABP measurements in small cattle was 0 ± 19 (-37 to 37) mmHg, 6 ± 18 (-77 to 48) mmHg, and 4 ± 16 (-73 to 48) mmHg, respectively. Mean difference between SABP, DABP, and MABP measurements in large cattle was -18 ± 32 (-107 to 71) mmHg, 7 ± 29 (-112 to 63) mmHg, and -5 ± 28 (-110 to 60) mmHg, respectively. The 95% LOAs for SABP, DABP, and MABP were -31 to +31, -19 to +44, and -19 to +34 mmHg, respectively in sheep and goats; were -37 to +37, -19 to +44, and -19 to +34 mmHg, respectively in small cattle; and were -81 to +45, -50 to +63, and -59 to +50 mmHg, respectively in large cattle.ConclusionsAgreement was poor between O-NIBP and IBP monitoring techniques.Clinical relevanceArterial BP should be monitored in anesthetized sheep, goats, and cattle using IBP. 相似文献
45.
E. Chakwizira J. M. de Ruiter A. L. Fletcher E. D. Meenken 《Grass and Forage Science》2014,69(1):182-190
Establishing the radiation‐use efficiency (RUE) of forage brassica crops will aid our understanding of their photosynthetic performance. The concept of RUE has been developed for cereals and legumes, but there is limited information for forage brassica crops. Three experiments defining the influence of different sowing dates on ‘Gruner’ kale (Brassica oleracea acephala L.) dry matter production were conducted at Hastings (Hawkes Bay) and Lincoln (Canterbury) in New Zealand between 2002 and 2009. These trials were also evaluated for radiation interception and RUE. Delayed sowing increased RUE in two out of three experiments across sites: from 1·93 g MJ?1 photosynthetically active radiation (PAR) for December‐sown crops to 2·72 g MJ?1 PAR (P < 0·001) for January‐sown crops at Hastings and from 1·50 for September‐sown crops to 2·00 g MJ?1 PAR (P < 0·001) for November‐sown crops at Lincoln. The different sowing dates and years of experimentation provided a range of mean temperatures (from 13 to 16°C) during the vegetative period. Across years and sowing dates, RUE was strongly correlated with mean temperature (R2 = 0·81) and sowing date (R2 = 0·64), but weakly correlated with season length (R2 = 0·11) and dry matter (R2 = 0·002). There was also a strong correlation (R2 = 0·83) between sowing date and mean temperature. The increase in RUE with delayed sowing was therefore mainly attributed to increased mean temperatures. Radiation‐use efficiency increased at about 0·41 g MJ?1 for each 1°C increase from 13 to 16°C. 相似文献
46.
阐述了我国农业面源污染现状以及我国农业面源污染防治立法的必要性,分析了现行农业面源污染防治立法的缺陷,并从立法理念、立法模式、法律制度等方面提出了完善现行农业面源污染防治立法方面的对策建议,以期从法律角度规范农业面源污染。 相似文献
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48.
《Scandinavian Journal of Forest Research》2012,27(1-4):379-386
This paper is an attempt to measure the supply consequences of the thinning subsidy which was in operation during the cutting season 1979/80. The econometric analyses are based on a questionnaire to a sample of 2500 private non‐industrial forest owners, which was produced by the official Swedish investigation SOU 1981:81. The analyses show that it is questionable whether the subsidy did affect the total cut. The estimates of the supply increase range from an average of zero to 122 m3/owner. As a by‐product we obtain estimates of the price elasticity of the private non‐industrial forest owners supply curve. These estimates range from 0.63 to 1.69. 相似文献
49.
票据无因性是指票据基础关系与票据法律关系的分离。它能保证持票人(尤其是正当持票人)的利益,促进票据流通的效率。文章从票据无因性最基本的概念出发,针对有关票据无因性的争论中出现的几种不同观点进行阐述和分析,并对我国票据立法中所体现的票据无因性原则进行分析和思考。 相似文献
50.