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1.
Silage and total mixed ration hygienic quality on commercial farms: implications for animal production 下载免费PDF全文
T. Cogan R. Hawkey E. Higgie M. R. F. Lee E. Mee D. Parfitt J. Raj S. Roderick N. Walker P. Ward J. M. Wilkinson 《Grass and Forage Science》2017,72(4):601-613
Implications of silage hygienic quality for animal production were investigated on forty‐five dairy farms in South West England. Samples of grass and maize silages and of total mixed rations (TMR) were obtained together with information on silage technology, herd size and animal production. Samples were analysed for mycotoxins, bacteria, yeasts, moulds and chemical composition. Thirteen mycotoxins were assayed, but none were detected in the samples of grass silage. However, mycotoxins were found in 0·9 of all maize and other silage samples, with deoxynivalenol and zearalenone predominating. There was no relationship between total mycotoxin concentration and mean lactation milk yield per cow. Enterobacteria counts tended to be higher in maize silage than in grass silage and higher still in TMR – a cause for concern. There were no relationships between mould counts and mycotoxin concentrations in silages, implying that mycotoxins may have been produced in the field pre‐ensiling. 相似文献
2.
A 4-month old, 200 kg, grey warmblood colt presented for a firm, non painful mass on the distal medial aspect of the left third metatarsus. Excisional biopsy revealed a diagnosis of haemangiosarcoma. Equine haemangiosarcoma is uncommon and only limited reports of successful treatment are available. The prognosis for survival is therefore considered to be poor. After two separate incidences of recurrence with incomplete excision of the tumour, intralesional treatment with cisplatin without excision or debulking was performed on three separate occasions. Intralesional cisplatin injection was performed at monthly intervals for three treatments. Four years post treatment with cisplatin, the horse remained in remission. This case report describes the diagnostic and treatment challenges for successful treatment of a primary haemangiosarcoma on the distal limb of a warmblood foal using intralesional cisplatin chemotherapy. 相似文献
3.
本论文研究了饲料加工的两个关键参数(调质温度和时间)对育肥猪颗粒饲料淀粉糊化度和维生素沉积的影响。日粮配方为含30%干酒糟及其可溶物的玉米-豆粕型基础日粮。整个试验中配方保持不变。本试验采用2×3双因子设计,调质温度分别为77℃和88℃,调质时间分别15秒、30秒和60秒。此外,本试验还设置一个对照组,对照组饲料不采用调质制粒工艺,而是采用粉料饲喂。因此,本试验共有7个处理组。采集调质后制粒前(热干粉)、制粒后冷却前(热制粒)、以及制粒冷却后(冷制粒)的样品,并分析这三种样品的总淀粉率、淀粉糊化 相似文献
4.
SCINTIGRAPHIC TRACKING OF MESENCHYMAL STEM CELLS AFTER PORTAL,SYSTEMIC INTRAVENOUS AND SPLENIC ADMINISTRATION IN HEALTHY BEAGLE DOGS 下载免费PDF全文
Mathieu Spriet Geraldine B. Hunt Naomi J. Walker Dori L. Borjesson 《Veterinary radiology & ultrasound》2015,56(3):327-334
Mesenchymal stem cells have been proposed to treat liver disease in the dog. The objective of this study was to compare portal, systemic intravenous and splenic injections for administration of mesenchymal stem cells to target the liver in healthy beagle dogs. Four healthy beagle dogs were included in the study. Each dog received mesenchymal stem cells via all three delivery methods in randomized order, 1 week apart. Ten million fat‐derived allogeneic mesenchymal stem cells labeled with Technetium‐99m (99mTc)‐hexamethyl‐propylene amine oxime(HMPAO) were used for each injection. Right lateral, left lateral, ventral, and dorsal scintigraphic images were obtained with a gamma camera equipped with a low‐energy all‐purpose collimator immediately after injection and 1, 6, and 24 h later. Mesenchymal stem cells distribution was assessed subjectively using all four views. Pulmonary, hepatic, and splenic uptake was quantified from the right lateral view, at each time point. Portal injection resulted in diffuse homogeneous high uptake through the liver, whereas the systemic intravenous injection led to mesenchymal stem cell trapping in the lungs. After splenic injection, mild splenic retention and high homogeneous diffuse hepatic uptake were observed. Systemic injection of mesenchymal stem cells may not be a desirable technique for liver therapy due to pulmonary trapping. Splenic injection represents a good alternative to portal injection. Scintigraphic tracking with 99mTc‐HMPAO is a valuable technique for assessing mesenchymal stem cells distribution and quantification shortly after administration. Data obtained at 24 h should be interpreted cautiously due to suboptimal labeling persistence. 相似文献
5.
The effects of mulching with perforated black plastic, in combination with fertilization and induced mycorrhizal symbioses, on the growth of loblolly pine (Pinus taeda L.) and yellow-poplar (Liriodendron tulipifera L.) were studied in a plantation under intensive, short rotation management. Mulching effects on soil temperature were also examined in order to assess the potential influence of this treatment on temperature-dependent processes in soils affecting tree growth. Mulching significantly increased height and stem diameter growth of both species, attributable largely to improved water relations resulting from diminished soil surface evaporation and elimination of transpirational losses from competing vegetation. Mulching effects on soil temperature were insufficient to contribute substantially to the growth response exhibited by mulched trees. Multiple applications of urea-N promoted enhanced growth in both loblolly pine and yellow-poplar, an effect accentuated by mulching, but the field performance of trees inoculated in the nursery with selected mycorrhizal fungi was poor relative to that of the other treatments investigated. 相似文献
6.
The effects of two controlled release fertilizers, Forestcote 22-4-6 + Minors and Dry Site 21-6-2 + Minors, and also dolomitic lime, on growth and nutrition of bareroot Jeffrey pine (Pinus jeffreyi Grev. & Balf.) were investigated. Forestcote, which consists of loose prills, and Dry Site, consisting of prepackaged prills, were administered with two rates, while a single liming rate was used. An acidic Sierra Nevada surface mine provided the study site, and all amendments were applied at outplanting to the backfill of augered planting holes. Without impacting survival, both fertilizer formulations enhanced seedling growth, particularly at a 16 g rather than an 8 g application rate, although Forestcote was marginally more effective in this regard. In contrast, liming at a 27 g rate induced severe mortality and offset much of the growth gains resulting from fertilization. Improvements in N and P nutrition, as revealed by foliar analysis, probably accounted for much of the growth stimulation exhibited by fertilized seedlings, but reductions in the uptake of potentially phytotoxic trace elements such as Mn and Al and increases in base cation/metallic element ratios likely also contributed. The high application rate was generally preeminent in eliciting these nutritional responses. Liming induced little alteration of seedling nutrition. Impaired water relations may have caused the unfavorable responses to this treatment. 相似文献
7.
Christoforos Karanikas Vincent Walker Apostolos Scaltsoyiannes Gilles Comte Cédric Bertrand 《Annals of Forest Science》2010,67(4):412-412
8.
Summary The deformation processes involved in wedge indentation of wood are described. The behaviour of wood is compared to that of an elastic-plastic solid and that of a cellular body. It approximates towards the former when its density is high and towards the latter when its density is low. The hardness of wood is examined as a function of density and of wedge angle.We wish to thank the University Grants Committee and the New Zealand Forest Service for supporting this work 相似文献
9.
Morphology and rooting of shoots developing in response to decapitation and pruning of Caribbean pine 总被引:2,自引:0,他引:2
The effects of decapitation at various levels, combined with heavy pruning of remaining branches, were examined for Caribbean pine. This treatment stimulated the development of shoots with long primary needles at all levels in the crown of trees aged one, four and eight years. Although a significant positive relationship between primary needle length and rooting was demonstrated, the very juvenile appearance of these shoots was not a reliable guide to rooting. There was an over-riding effect on rooting of the ortet age × level in crown × decapitation height treatment. Decapitated trees provided shoots of higher rooting capacity than intact trees for the one and four, but not the eight year old trees. Shoots developing in the lower crown in response to decapitation and heavy pruning of four year old trees displayed a high level of rooting-equivalent to that of shoots from the decapitated and pruned one year old trees. 相似文献
10.
Kyle E. Walker 《Growth and change》2017,48(4):532-551
Recent estimates that central cities are growing faster than their suburbs in the U.S. have captured the attention of both academics and the popular media. Many commentators have used these numbers to claim that internal migration trends in the U.S. have reached a turning point, in which migrants increasingly prefer urban residences to suburban locales. However, these assertions often rely on problematic definitions of city and suburb, and pay too little attention to demographic variations among migrants. This paper examines whether recent internal migrants in the U.S. are choosing closer‐in destinations, drawing from microdata samples from the American Community Survey since 2005. During this period, there is an overall trend of migrants to the largest metropolitan areas in the U.S. choosing to migrate closer to the metropolitan core. However, this trend varies significantly among major demographic groups; whereas younger, single, educated, and white‐collar migrants show evidence of a return to the core, migrants who are blue‐collar, less‐educated, older, and with families remain more suburban. In turn, this analysis suggests that overall trends of “back to the city” migration are producing considerable divergence in the metropolitan destinations of different demographic groups. 相似文献