U.S. flagAn official website of the United States government
                    Here's how you know **Official websites use .gov**
                            
                            A **.gov** website belongs to an official government organization in the United States.
 **Secure .gov websites use HTTPS**
                            
                            A **lock** (                            
                              A locked padlock                                                      
                            
                            ) or **https://** means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.


Menu Agricultural Research Service
						
                    U.S. DEPARTMENT OF AGRICULTURE
 close



Research
                Research Home
                            National Programs
                            Research Projects
                            Scientific Manuscripts
                            International Engagement
                            Scientific Software/Models
                            Databases and Datasets
                            Office of Scientific Quality Review
            Media
                News & Features
                            Multimedia
                            Briefing Room
                            Down on the Farm
                            Press Room
                            Science in Your Shopping Cart
                            Scientific Discoveries
                            Tellus
                            Under the Microscope
            About ARS
                About ARS Home
                            Staff Directory
                            Labs and Research Centers (Map)
                            Headquarter Offices
                            Organizational Chart
                            Employee Services (REE Employees Only)
                            Office of Outreach, Diversity, and Equal Opportunity
            Work With Us
                Work With Us Home
                            ARS Vacancies at USAJOBS
                            Careers at ARS Information
                            Scientific Collaborations
                            Extramural Agreements
                            1890 Faculty Research Sabbatical ProgramSearch small
                    Search
            
            ARS Home
                                About ARS
                                Contact Us




ARS Home Research Publications at this Location





- ARS National Programs
- Search for a scientific manuscript
- Search for a research project
- ARS Software
- Programs and Projects
- Collaborations
- Subjects of Investigation
- Publications

Title:   Author  item
                                            LINDSAY, D - VIRGINIA TECHitem
                                            BLAGBURN, B - AUBURN UNIVERSITYitem
                                            Dubey, Jitender
  Submitted to: Veterinary Parasitology
                                    Publication Type: Peer Reviewed Journal
                                    Publication Acceptance Date: 12/27/2001
                                    Publication  Date: N/A
                                    Citation: N/AInterpretive Summary: Infections by the single-celled parasite Toxoplasma gondii are widely prevalent in animals and humans.  It causes mental retardation and loss of vision in children.  Humans become infected by ingesting parasites encysted in meat or by ingesting food and water contaminated with the resistant stage of the parasite (oocyst) excreted in feces of infected cats.  Oocysts swhen excreted in feces are unsporulated (not infective) and become infective after 1-2 days outside in the environment.  Scientists at the Beltsville Agricultural Research Center and the Virginia Tech, Blacksburg have found that oocysts stored in refrigerator for 11 weeks were still capable of sporulating.  These findings will be of interest to biologists, parasitologists and public health workers.
                                Technical Abstract: Toxoplasma gondii oocysts are excreted nonsporulated in the feces of cats into the environment.  These oocysts must undergo sporulation to become infectious.  Little is known about the factors that influence sporulation of T. gondii oocysts.  The present study examined survival of nonsporulated oocysts under refrigerated conditions over an 11 week observation period.  Microscopic examination of oocysts indicated that no visible development occurred under refrigerator conditions.  The nonsporulated oocysts retained their ability to sporulate when placed at room temperature.  The numbers of visually viable appearing oocysts decreased over time.  Some oocysts in all samples were infectious for mice despite being refrigerated for up to 11 weeks before undergoing sporulation.  Results indicate that nonsporulated oocysts can survive in the environment for at least 3 months and retain their ability to become infectious when placed under appropriate  conditions.


Return to top


Connect with ARS Sign up


ARS Home
                            USDA.gov
                            Plain Writing
                            Policies & Links
                            Civil Rights Statements
                            FOIA
                            Accessibility Statement
                            Privacy Policy
                            Non-Discrimination Statement
                            Quality of Information
                            USA.gov
                            WhiteHouse.gov