Study of the clinical effects of postoperative parenteral nutrition in 15 horses     

Durham AE  Phillips TJ  Walmsley JP  Newton JR 《The Veterinary record》2003,153(16):493-498

Several clinical variables were compared in two groups of 15 horses recovering from resection and anastomosis of a strangulated small intestine; 15 were treated with parenteral nutrition and 15 were starved routinely. There was some evidence that parenteral nutrition had a short-lived adverse effect on both the catheter sites and gastric emptying, but there were no marked adverse clinical effects and no evidence of any improvement in the horses' condition.  相似文献   

Effect of photoperiod on milk yield and quality, and reproduction in dairy goats     

R. Garcia-Hernandez  G. Newton  S. Horner  Lou C. Nuti   《Livestock Science》2007,110(3):214-220

The objective of this study was to examine the effect of long day photoperiod (LDPP) on milk production and reproduction in milk goats. A total of 79 goats were randomly assigned to three treatment groups blocked by day of kidding. Group 1 (Gr1, n = 26) was subjected to natural photoperiod from January 6 to December 5. Group 2 (Gr2, n = 24) was subjected to LDPP (20 h light, 4 h dark) from June 22 to December 5. Group 3 (Gr3, n = 29) was subjected to LDPP from January 6 to December 6. Weekly milk weights and samples were collected for fat, protein and somatic cell count (SCC) determinations. Blood serum was harvested for progesterone (P4) determination. Results indicated a significant effect (p < 0.001) between treatments for body weight changes, feed intake and milk yield. Both light treated groups had a significantly higher (p < 0.001) average daily milk output for the entire lactation period than the control group (G1, 2.193 kg/day; G2, 2.517 kg/day; G3, 2.305 kg/day). Milk fat for the overall lactation was significantly higher in Gr3 (+ 0.19 g/100 ml) than for Gr2 (+ 0.06 g/100 ml) when compared to the control group (x g/100 ml) under natural photoperiod. Somatic cell counts throughout lactation were significantly (p < 0.001) lower for Gr2 (1.70 million/ml) and higher for Gr3 (2.03 million/ml), with the control group (Gr1) having an intermediate level (1.96 million/ml). Progesterone levels between June 9 and August 30 indicated that 27%, 48% and 63% of the animals had P4 levels in excess of 1.0 ng/ml serum for Gr1, Gr2 and Gr3, respectively. Pregnancy diagnosis by ultrasound in December revealed that a high number of does in the light treated groups (10 of 37) were pseudo-pregnant when compared with the control group (1 of 21). Although light appeared to be effective in increasing milk production, further investigations are needed to evaluate the effect of LDPP on pseudo-pregnancy in dairy goats.  相似文献   

A practitioner's guide to understanding equine infectious disease diagnostics in the United Kingdom. Part 1: How to optimise sampling approaches and a guide to agent detection testing methods     

F. M. Whitlock  J. R. Newton 《Equine Veterinary Education》2022,34(6):330-336

Diagnostic testing is routinely performed by the equine clinician when dealing with suspected infectious disease cases and outbreaks. Optimal sample timing, choice and handling are fundamental to attain an accurate diagnosis, and a good understanding of laboratory-based sample analysis techniques, and their validation is necessary for effective diagnostic test result interpretation. This two-part series highlights the importance of interpreting results bearing testing limitations and specific clinical findings in mind, and on these foundations, the treating clinician should always be well placed to deal with equine infectious diseases. Part 1 in this series will provide a treating clinician with an overview of the importance of testing horses in infectious disease outbreaks and how this is achieved. The different laboratory testing options available for agent detection and their methods will also be discussed. Part 2 will summarise serological (antibody) testing techniques, sample processing (including how tests are performed and validated) and result interpretation.  相似文献   

抗生素对火炬松的器官发生植株再生的影响(英文)     

Latoya Harris  Ronald J.Newton 《林业研究》2003,14(3)

本文研究了氨苄青霉素、羧苄青霉素和头孢霉素等3种抗生素对火炬松愈伤组织的生长和分化及不定芽生根的影响。结果表明,头孢霉素最有利于愈伤组织的诱导和生长,羧苄青霉素最有利于芽的分化,氨苄青霉素降低了不定芽的生根频率。所有试验的3种抗生素提高愈伤组织的形成和芽再生,但降低了芽的生根频率。这些结果表明,选择合适的抗生素对优化火炬松遗传转化体系有重要作用。图3表4参25。  相似文献   

Plant biotechnology: A case study ofBacillus thuringiensis (Bt) and its application to the future of genetic engineered trees     

Tang Wei  Latoya Harris  Ronald J. Newton 《林业研究》2004,15(1):1-10

Agricultural productivity may be raised in a sustainable way by many different technologies such as biological fertilizers, soil and water conservation, biodiversity conservation, improved pest control, and changes in land ownership and distribution. Of these measures, biotechnology applications probably hold the most promise in augmenting conventional agricultural productivity, because biotechnology applications give not only the need to increase production, but also protect the environment and conserving natural resources for future generations. Biotechnology applications will have the possibilities to increase productivity and food availability through better agronomic performance of new varieties, including resistance to pests; rapid multiplication of disease-free plants; ability to obtain natural plant products using tissue culture; diagnosis of diseases of plants and livestock; manipulation of reproduction methods increasing the efficiency of breeding; and the provision of incentives for greater participation by the private sector through investments. Insect resistance through the transfer of a gene for resistance fromBacillus thuringiensis (Bt) is one of the most advanced biotechnology applications already being commercialized in many parts of the world. This paper reviews the development and the status ofBt technology and application ofBt transgenic plants in current agriculture, and discusses specific issues related to the transfer of the technology to the future of genetic engineered trees with emphasis on conifers. Biography: Tang Wei (1964-), male, Ph. Doctor, Research associate, Department of Biology, Howell Science Complex, East Carelina University, Greenville, NC 27858-4353, USA. Responsible editor: Chal Ruihai  相似文献   

与生长激素相关的高等植物细胞周期生化调控     

唐巍 《林业研究》2004,15(3)

高等植物细胞周期是细胞生物学上的重要研究领域。细胞周期受遗传和发育影响因素的调控。本文综述高等植物细胞周期中涉及到细胞周期关卡GO-G1-S期和G2-M期的激素调控。最新研究成果证明玉米素、腺嘌呤、激动素、赤霉素和脱落酸等通过细胞周期蛋白依赖性蛋白激酶及细胞周期关卡的脱磷酸化控制细胞周期。植物D-型细胞周期蛋白也已被证明在细胞周期调控中起关键作用。本文有关细胞周期的研究综述对植物细胞和发育生物学研究有参考价值。图3参61。  相似文献   

Diurnal changes in water conduction in loblolly pine (Pinus taeda) and Virginia pine (P. virginiana) during soil dehydration     

Wakamiya-Noborio I  Heilman JL  Newton RJ  Messina MG 《Tree physiology》1999,19(9):575-581

We studied diurnal changes in water conduction during soil dehydration in 37-month-old seedlings of one Virginia pine (Pinus virginiana Mill.) and two loblolly pine (P. taeda L.) sources, one from North Carolina (NC) and the other from the "Lost Pines" areas of Texas (TX), in an environmentally controlled growth chamber. For seedlings of similar biomass, the TX source had higher values of transpiration, needle conductance, and plant hydraulic conductivity under well-watered conditions than the NC source. Under dry soil conditions, the TX source had lower values of water conduction than the NC source. The Virginia pine source responded similarly to the TX source under both well-watered and dry soil conditions. For all three pine sources, gradients between soil and needle water potentials were greatest when the seedlings were moderately stressed. The TX and Virginia pine sources had higher gradients and lower daytime needle water potentials under moderate stress conditions than the NC source. Predawn needle water potentials did not differ among the pine sources. We conclude that the TX and Virginia pine sources have decreased daytime needle water potentials and increased water potential gradients during the daytime under moderate stress conditions, but with no disruption of recovery at predawn. The greater rates of transpiration and water conduction by the TX source compared with the NC source under well-watered conditions suggest a means by which growth can be maximized prior to the onset of drought, thereby enhancing survival of loblolly pines in drought-prone environments.  相似文献   

The biochemical control of the cell cycle by growth regulators in higher plants     

TANGWei LatoyaHarris RonaldJ.Newton 《林业研究》2004,15(3):227-232

The cell cycle is an important research field in cell biology and it is genetically and developmentally regulated in animals and plants. The aim of this study was to review knowledge about the biochemical regulation of the cell cycle by plant growth regulators through molecular checkpoints that regulate the transition from G0-G1-S-phase and G2-M in higher plants.Recent research has shown that zeatin treatment led to the up-regulation of CycD3 in Arabidopsis. Benzyladenine treatment can also shorten the duration of S-phase through recruitment of latent origins of DNA replication. Kinetin is involved in the phosphoregulation of the G2-M checkpoint; the major cyclin-dependent kinase (Cdk) at this checkpoint has recently shown to be dephosphorylated as a result of cytokinin treatment, an effect that can also be mimicked by the fission yeast Cdc25 phosphatase. Gibberellic acid (GA) treatment induces internode elongation in deepwater rice, this response is mediated by a GA-induced up-regulation of a cyclin-Cdk at the G2-M checkpoint. Recent evidence has also linked abscisic acid to a cyclin-dependent kinase inhibitor. A new D-type cyclin, recently discovered in Arabidopsis may have a key role in this process. A brief review on plant growth regulator-cell cycle interfacing during development and a cytokinin-induced continuum of cell cycle activation through the up-regulation of a plant D-type cyclin at the G1 checkpoint and the phosphoregulation of the Cdk at the G2/M checkpoint had been concluded. This review could be valuable to research on cell and developmental biology in plants.  相似文献   

植物生物技术:苏云金杆菌抗虫基因的研究和它对未来树木遗传工程的影响     

唐巍  LatoyaHarris  RonaldJ.Newton 《林业研究》2004,15(1):1-10,J001

许多不同的技术可以促进农业生产力的持续增长，生物技术是其中最重要和最有前途的方法。因为生物技术不仅可以增加生产力。而且在环境和自然资源的保护中起重要作用，应用生物技术可以生产高产、优质、高抗性和无病植物，同时也可以提高育种效率和促进食品的工业化生产。苏云金杆菌抗虫基因是目前生物技术领域中应用最广泛的例子之一。由此而产生的抗虫植物正在广泛应用于世界各地的商业化生产。本文综述了苏云金杆菌抗虫基因的研究进展和它在未来林木遗传工程中的应用。表4参68。  相似文献   

Effect of Breeding Activity on the Microflora of the External Genitalia and in the Semen of Stallions,and the Relationship Between Micro‐organisms on the Skin and on the External Genitalia     

T Guimarães  C Miranda  M Pinto  E Silva  L Damásio  AL Costa  MJ Correia  JC Duarte  C Cosinha  G Lopes  G Thompson  A Rocha 《Reproduction in domestic animals》2014,49(6):926-933

A possible role of breeding activities in the composition of the microbial population in stallions' external genitalia (EG) and the relationship between micro‐organisms colonizing the skin of the abdomen and the ones colonizing the EG have not been studied. In experiment 1, EG microbiological samples were collected from 41 stallions used for both natural cover and semen collection (BST) and from 18 non‐breeding stallions (NBST). A higher (p < 0.05) frequency of isolation of potentially pathogenic species was found for BST. Age did not influence number of micro‐organism species isolated both in BST and NBST. In experiment 2, the microbial content of the EG and semen was compared in 23 BST. Most micro‐organisms isolated from the EG were present in semen, albeit with a numerically lower prevalence. In 7 stallions, six microbial species isolated from semen were absent from the EG cultures, suggesting contamination by the operator. In experiment 3, a numerically higher number of micro‐organism species was isolated from the EG of 31 stallions, than from their skin of the ventral abdomen in contact with the penis or from the skin of the thorax. With the sole exception of Escherichia coli, potentially pathogenic bacteria were only isolated from the EG but not from the skin. Results suggest that breeding activity increased the number of species colonizing the EG; most species isolated from the EG were also found in semen even if with a lower frequency, and additional semen contamination seemed to occur during its manipulation. Many micro‐organism species of the skin were also isolated from the penis, but independently of being or not in contact with the penis, skin did not seem to provide an adequate environment for the growth of potentially pathogenic bacteria that were isolated from EG, with the sole exception for E. coli.  相似文献