水稻株型育种生理生态特性的研究现状与展望   总被引：21，自引：0，他引：21  

王建林  徐正进  魏树和 《辽宁农业科学》2000,(4):23-27

阐述了株型育种发展的阶段及各阶段的特点,从茎、叶、穗、分蘖、根５个方面与水稻株型育各种有关的各种形态、生理、生态特性的研究现状进行了综合评述。认为株高增加、叶片直立、分蘖力适中、根系发达不早衰是株型育种目标的共同点,而北方粳稻区穗子直立更有利于提高光能利用率。认为通过籼粳稻杂交、水陆稻杂交,并进行多次人回交或复交,将非Ｆ１优势固定或通过籼粳杂交转能广亲和材料采用“架桥”的方法,是实现优化性状组配的  相似文献   

Energy utilization by pregnant and non-pregnant heifers.     

C L Ferrell  W N Garrett  N Hinman  G Grichting 《Journal of animal science》1976,42(4):937-950

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Monitoring and surveillance in abattoirs of residues of antibacterial substances – a description of programs in Australia and the USA     

JL CUPIT  NL BLACKMAN†  TJ NICHOLLS†  IB STEPHENS†  RJ WILD 《Australian veterinary journal》1994,71(12):400-403

SUMMARY Australia and the USA are major international meat exporting countries. Both countries conduct programs to monitor and survey for antibacterial residues. Australian programs use a urine screening test, whereas the US programs use tissue fluids as the test medium. The development of surveillance programs to provide rapid feedback to producers is a feature of the Australian programs. The programs in each country compare favourably with regard to numbers of animals tested, results and action taken to prevent residues. The results of the Australian programs justify the promotion of a ‘clean food’ image for Australian meat products with respect to antibacterial drugs.  相似文献   

Coastal dynamics     

Garrett C 《Science (New York, N.Y.)》1983,220(4599):849-850

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Recent Developments in Oestrous Synchronization of Postpartum Dairy Cows with and without Ovarian Disorders   总被引：1，自引：0，他引：1  

JL Yániz  K Murugavel  F López-Gatius 《Reproduction in domestic animals》2004,39(2):86-93

This report reviews the most recent developments in prostaglandin‐based oestrous synchronization programmes for postpartum dairy cows and addresses the efficiency of controlled breeding protocols based on such developments for cows with abnormal ovarian conditions. A double prostaglandin protocol applied 11–14 days apart seems to be capable of bringing most cows to oestrus. Because of varying oestrus onset times, improved conception rates are obtained following artificial insemination (AI) at detected oestrus rather than fixed‐time AI in prostaglandin‐treated cows. The administration of oestradiol or human chorionic gonadotrophin, or both these hormones, after prostaglandin treatment, improves the synchrony of oestrus yet does not enhance the conception rate. Progesterone‐based treatments for oestrous synchronization are considered the most appropriate for non‐cyclic or anoestrous postpartum dairy cows; prostaglandin alone being ineffective because of the absence of a mature corpus luteum in these cows. Improved oestrus synchrony and fertility rate have been reported using short‐term progesterone treatment regimes (7–9 days) with or without oestradiol benzoate combined with the use of a luteolytic agent given 1 day before, or at the time of, progesterone withdrawal. The ovulation synchronization (Ovsynch) protocol, based on the use of gonadotrophin releasing hormone and prostaglandin, was developed to coordinate follicular recruitment, CL regression and the time of ovulation. This protocol allows fixed time insemination and has proved effective in improving reproductive management in postpartum dairy cows. However, timed AI following Ovsynch seems to have no beneficial effects in heifers, because of an inconsistent follicle wave pattern, and in anoestrous cows, given their lack of prostaglandin responsive CL. To date, there are several prostaglandin based, fixed‐time insemination oestrous synchronization protocols for use in early postpartum dairy cows with ovarian disorders such as ovarian cysts and acyclicity.  相似文献   

Skin lesions caused by orthopoxvirus infection in a dog     

Smith KC  Bennett M  Garrett DC 《The Journal of small animal practice》1999,40(10):495-497

A seven-year-old male dobermann was presented for examination of a non-pruritic ulcerated lesion occurring at the site of a suspected rat bite on the muzzle. Biopsy revealed focal ulcerative dermatitis, with cells in the epidermis, follicular infundibula and interposed sebaceous glands undergoing ballooning degeneration and containing large acidophilic intracytoplasmic structures resembling poxvirus inclusion bodies. The diagnosis of orthopoxvirus infection was confirmed by transmission electron microscopy and immunohistochemistry. The biopsy site healed uneventfully, without evidence of recurrence or development of further cutaneous or internal lesions, and a serum sample collected eight weeks after first presentation had a low titre of poxvirus antibodies. This report demonstrates that orthopoxvirus infection should be considered as a cause of ulcerative skin lesions in dogs, particularly if there has been recent contact with rodents or other small mammals.  相似文献   

Low-Dose Insemination in Pigs: Problems and Possibilities     

JM Vazquez  J Roca  MA Gil  C Cuello  I Parrilla  I Caballero  JL Vazquez  EA Martínez 《Reproduction in domestic animals》2008,43(S2):347-354

Low-dose AI procedures are required by the pig industry to efficiently utilize emerging sperm technologies, such as cryopreservation and sex-sorting. Currently, several different procedures for inseminating with a low or very low number of spermatozoa have been described. Deep intrauterine insemination allows the deposition of the spermatozoa in the depth of the uterine horn, allowing a significant reduction in the number of spermatozoa inseminated with maintenance of optimal reproductive performance. Intra-oviductal laparoscopic insemination has been recently applied in pigs. This technique has proved to be applicable with diluted and sex-sorted spermatozoa. This review discusses several problems encountered during the development of deep intrauterine insemination and intra-oviductal laparoscopic insemination of pigs and provides potential solutions for the practical application of both the technologies.  相似文献   

Plant-virus interactions and the agro-ecological interface     

H. M. Alexander  K. E. Mauck  A. E. Whitfield  K. A. Garrett  C. M. Malmstrom 《European journal of plant pathology / European Foundation for Plant Pathology》2014,138(3):529-547

As a result of human activities, an ever-increasing portion of Earth’s natural landscapes now lie adjacent to agricultural lands. This border between wild and agricultural communities represents an agro-ecological interface, which may be populated with crop plants, weeds of crop systems, and non-crop plants that vary from exotic to native in origin. Plant viruses are important components of the agro-ecological interface because of their ubiquity, dispersal by arthropod vectors, and ability to colonize both crop and wild species. Here we provide an overview of research on plant-virus dynamics across this interface and suggest three research priorities: (1) an increased effort to identify and describe plant virus diversity and distribution in its entirety across agricultural and ecological boundaries; (2) multi-scale studies of virus transmission to develop predictive power in estimating virus propagation across landscapes; and (3) quantitative evaluation of the influence of viruses on plant fitness and populations in environmental contexts beyond crop fields. We close by emphasizing that agro-ecological interfaces are dynamic, influenced by the human-mediated redistribution of plants, vectors, and viruses around the world, climate change, and the development of new crops. Consideration of virus interactions within these environmentally complex systems promises new insight into virus, plant, and vector dynamics from molecular mechanisms to ecological consequences.  相似文献   

Changing Regional Emissions of Airborne Pollutants Reflected in the Chemistry of Snowpacks and Wetfall in the Rocky Mountain Region,USA, 1993–2012     

George P. Ingersoll  Debra C. Miller  Kristi H. Morris  Jill A. McMurray  Garrett Port  Brian S. Caruso 《Water, air, and soil pollution》2016,227(3):94

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Nutrition change strategies: the new frontier     

McLachlan M  Garrett J 《Public health nutrition》2008,11(10):1063-1075

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