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Atsakymai kurių autorius Lambyland

  4. PAŠARAI: Ganyklų žolė, šienas ir kiti pašarai

    forume Avininkystė

    Paskelbta

    Viskas priklauso nuo ganyklų kokybės .kuo geresne-tuo daugiau gali laikyti SGV.knygelese ir čia forume,tiesiog reikia nepatingeti ir perskaityti viską nuo A iki Z ir daug kas paaiškės.,rekomenduojama laikyti 10 eriavedziu su prieaugliu.kiti,kaipir aš laikome ir 20 ir daugiau viename ha,tiesiog pigiau nusipirkt pasarus,nei pačiam auginti:)

    Aš irgi susizavejau avininkyste praeitais metais,ir po šiai dienai esu proceso kuryme.

    Sekmės ir kantrybės

  10. Žuvų ligos

    forume Žuvininkystė

    Paskelbta

    Tai nekenkia kalio pergamanatas?jei 5 arak,tai kiek cia pilt reiketu,nes as kaip suprantu irgi atsiveziau vedrodiniu karpiu rudeni,ta kasdien po 2-3 kilograminius amurus istraukiu pilvais isvirtusiais.dar pasirodo ratanai uzsiveise,tai jau nebezinau ir ka bedaryti

  14. Veislines eriavedes is EU

    forume Avininkystė

    Paskelbta

    Jei kam idomu del genomo

    Scrapie is an infectious disease of sheep that affects the central nervous system and is always fatal.  Upon necropsy, infected animals will have holes or vacuoles in the tissue of the brain.  The disease is classified as a transmissible spongiform encephalopathy (TSE).    Some TSE’s in other species include bovine spongiform encephalopathy (BSE, Mad Cow Disease), Creutzfeldt-Jakob Disease (CJD) in man, new variant CJD (vCJD) in man thought to result from eating meat from BSE-infected cattle, transmissible mink encephalopathy (TSE), chronic wasting disease (CWD) in some U.S. populations of deer and elk, and feline spongiform ecephalopathy (FSE).  Federal and State animal health authorities have considered scrapie a high priority disease for elimination for many years, but the relatively recent evidence that ties vCJD in humans to BSE in cattle has resulted in increased attention on scrapie in sheep.

     

    Incidence

     

    Scrapie was first diagnosed in the U.S. in 1947 in a flock of Suffolk sheep in Michigan that had imported sheep from Canada of U.K. origin for several years.  From 1947 through July 2001, scrapie had been diagnosed in over 1,000 flocks, and approximately 1,600 individual cases of natural sheep scrapie and 7 individual cases of natural goat scrapie have been found (Sutton, USDA/APHIS/VS, personal communication).  Through 1992, the breed distribution was as follows: 87% Suffolk, 6% Hampshire, and 7% other breeds (Border Leicester, Cheviot, North Country Cheviot, Corriedale, Cotswold, Dorset, Finnsheep, Merino, Montadale, Rambouillet, Shropshire, and Southdown) and crosses (Detwiler et al., 1996; Wineland et al., 1998, USDA, 1999).  While 1,600 appears to be a large number of cases of sheep scrapie, it actually is not since it represents an average of only about 30 cases per year.  Relative to most other sheep diseases, the incidence of scrapie is quite low.

     

    Clinical signs

     

    Early signs of scrapie include subtle changes in behavior and temperament.  These changes may be followed by scratching and rubbing against fixed objects.  Other signs are loss of coordination, weight loss despite a good appetite, biting of feet and limbs, and lip smacking.  Gait abnormalities such as high-stepping of the forelegs, hopping like a rabbit, and swaying of the back end may be seen.  Signs or effects of scrapie usually do not appear until 2 to 5 years after an animal is infected.  Sheep may live 1 to 6 months (sometimes longer) after the onset of clinical signs (USDA, 1999).

     

    Infected animals show no immune response to the infective agent as is the case with viral and bacterial diseases.  There is currently no live-animal test to determine if an animal is infected.  This is a major area of research, and some promising live-animal tests are in the development and evaluation stages.

     

    The scrapie agent is thought to be spread most often from ewe to offspring and to other lambs in contemporary lambing groups through contact of lambs with the placenta and placental fluids of infected ewes (USDA, 1999).  Lateral transmission from infected rams to ewes and lambs, from infected ewes to other ewes, and from an infected environment to adult animals are not thought to be major routes of transmission; although there are documented cases of scrapie where such routes of transmission are thought to have occurred.

     

    There is not agreement among scientists on the nature of the infectious agent.  However, infected animals have large amounts of an abnormal type of prion protein (denoted as PrPSc), especially in the central nervous system tissues of the brain and spinal cord.  Scrapie-free animals have normal prion protein (PrPC) and no PrPSc.  Some feel that PrPSc itself is the infectious agent (Prusiner, 1998) while others feel that PrPSc is the result of another infectious agent.  However, scientific evidence increasingly supports the theory of PrPSc itself as the infectious agent.  Dr. Stanley B. Prusiner, University of California, San Francisco was awarded the 1997 Nobel Prize in Physiology or Medicine for his work on the infectious nature of prions.  The infectious agent is extremely resistant to heat and to normal sterilization procedures.

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