Nuclear transplantation in bovine embryos   总被引：9，自引：0，他引：9  

J M Robl  R Prather  F Barnes  W Eyestone  D Northey  B Gilligan  N L First 《Journal of animal science》1987,64(2):642-647

This study was conducted to develop a method for transplanting nuclei in bovine embryos and to test the development of several stages of donor nuclei transplanted to enucleated pronuclear recipient embryos. Pronuclear embryos were centrifuged to reveal nuclei. Nuclei were removed without penetrating the plasma membrane as membrane-bound karyoplasts, and were inserted into enucleated zygotes by electrically induced cell fusion. The highest rate of fusion (79%) occurred in Zimmerman Cell Fusion medium at 100 V for 20 to 40 microseconds with the fusion membranes oriented parallel to the electrodes. The effect of nuclear transplantation on development was tested in pronuclear embryos in which nuclei were removed and reinserted and the embryos were then transferred to sheep oviducts for 5 d. Of the intact nuclear transplant embryos recovered, 5/29 (17%) developed to morulae or blastocysts compared with 11/30 (37%) of the non-manipulated embryos. Two nuclear transplant embryos were transferred to a recipient cow, and both developed to normal offspring. When nuclei from two-, four-, or eight-cell embryos were transplanted to pronuclear recipient embryos, no development was observed.  相似文献   

Serologic evidence of infectious bursal disease virus infection in Iowa turkeys     

H J Barnes  J Wheeler  D Reed 《Avian diseases》1982,26(3):560-565

Two infectious bursal disease viruses (IBDVs)--a cell-culture-adapted chicken strain designated Edgar strain and a recent isolate from turkeys in Missouri--were used to assay sera from 10 Iowa turkey flocks collected between 1 and 16 weeks of age. The two viruses were serologically distinct in cross-neutralization tests. For all flocks, a similar serologic pattern was found consisting of (1) low maternal antibody titers to turkey IBDV and occasionally to Edgar strain IBDV between 1 and 3 weeks of age, (2) a period of very low or no detectable titers between 3 and 7 weeks of age, and (3) sharply rising high titers to turkey IBDV with low titers to Edgar IBDV beginning at 5 to 8 weeks of age. These findings indicate that infection with IBDV of the serotype represented in this study by the turkey isolate is common in Iowa turkey flocks, whereas infection with IBDV represented by Edgar strain is uncommon. Infection occurred between 3 and 7 weeks of age during the late brooding period or after birds had been moved to an intermediate growing facility. All flocks developed complicated respiratory disease with excessive mortality caused by Escherichia coli septicemia, typically between 3 and 6 weeks of age. Although there was a temporal relationship between IBDV infection and respiratory disease, the possible role of IBDV in the process is unknown.  相似文献   

Inclusion-body hepatitis in day-old turkeys     

J S Guy  J L Schaeffer  H J Barnes 《Avian diseases》1988,32(3):587-590

Inclusion-body hepatitis was diagnosed in 1-day-old turkeys experiencing above-average mortality. At necropsy, turkeys appeared anemic and had pale yellow livers. Histopathologic examination of affected livers revealed diffuse hepatic degeneration and multifocal necrosis, with approximately 70% of the hepatocytes containing large, basophilic, intranuclear inclusion bodies. An adenovirus was isolated from affected livers and identified as a group I avian adenovirus by indirect immunofluorescence.  相似文献   

Effect of genetic selection for milk yield and increased milking frequency on plasma growth hormone and prolactin concentration in Holstein cows     

G W Kazmer  M A Barnes  R M Akers  R E Pearson 《Journal of animal science》1986,63(4):1220-1227

Fifty Holstein cattle, either second to fourth generation daughters of cows randomly bred to non-commercial sires originating in the Virginia Tech dairy herd (estimated mean PDM84 = -455 kg, control animals), or daughters of cows bred to commercially available sires (mean PDM84 = +368 kg, selection animals), were randomly assigned to be milked twice or thrice daily starting at parturition. Serial blood samples were collected via jugular cannulae at 30, 90 and 200 d post-partum (DPP) during both the first and second lactations. Blood samples were collected for 3 h prior to and 4 h following thyrotropin releasing hormone (TRH) administration, and were analyzed for growth hormone (GH) and prolactin (PRL) concentrations. Dry matter intake, body weight and milk yield and fat content were used to calculate net energy balance (NEB) of animals at each DPP sampling period. Mean plasma GH concentrations were greater (P less than .01) in selection vs control animals both before and after TRH administration, and decreased (P less than .01) with advancing lactation (30 greater than 90 greater than 200 DPP). However, NEB was not influenced by genetic merit, implying that observed differences in GH concentrations were not due to that trait. Plasma PRL concentrations were not affected by genetic merit or DPP, but were greater (P less than .01) in the second vs first lactation. Neither PRL or GH concentrations were affected by frequency of milking. The results support the contention that increased plasma GH concentrations are associated with selection for increased milk yield.  相似文献   

Intestinal cryptosporidiosis and reovirus isolation from bobwhite quail (Colinus virginianus) with enteritis     

G D Ritter  D H Ley  M Levy  J Guy  H J Barnes 《Avian diseases》1986,30(3):603-608

An acute enteric disease of young pen-raised bobwhite quails was studied. Affected quails had white, watery diarrhea accompanied by dehydration and subsequent death. Mortality from hatch to 17 days of age ranged from 30 to 45% in the three flocks examined. Small intestines were thin-walled and distended with fluid and gas. Microscopic lesions in the intestinal tract consisted of villus atrophy, villus fusion, and sloughing of cells at the tip of the villi in duodenum, jejunum, and ileum. Cryptosporidium sp. and reovirus were identified in affected quails.  相似文献   

Acute airsacculitis in turkeys inoculated with Pasteurella multocida     

M D Ficken  H J Barnes 《Veterinary pathology》1989,26(3):231-237

Thirty female turkeys, inoculated into the caudal thoracic air sacs with Pasteurella multocida were examined from 0 to 6 hours post-inoculation (PI). The air sac reacted rapidly and intensely with exudation of heterophils. Circulating leukocyte and thrombocyte numbers remained normal except for an absolute lymphopenia by 6 hours PI. P. multocida was initially isolated from blood at 3 hours PI. Total cell counts increased markedly in air sac lavage fluids by 1.5 hours PI and continued to increase until 6 hours PI. Heterophils predominated in lavage fluids (greater than 94%), with macrophages comprising the remaining cells. Microscopically occasional heterophils were present within air sac blood vessels and perivascularly by 0.5 hour PI. They became more numerous by 1.5 and 3 hours PI when transepithelial migration into the air sac lumen was seen. By 6 hours PI, there was diffuse, severe swelling of air sac epithelium and mesothelium, and bacteria were located in air sac interstitium. Ultrastructurally, endothelial and air sac epithelial cells were swollen and vacuolated Interdigitating processes of air sac epithelial cells were separated. These results indicate that air sacs can be the portal of entry for P. multocida into the systemic circulation, probably via damaged air sac epithelium.  相似文献   

Sectional notes     

Frank E. Garret  Geo D. Ruehle  Verne C. Beverly  H. J. Evans  W. C. Barnes  R. E. Goodin 《American Journal of Potato Research》1948,25(3):92-100

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The microbiology and sensory evaluation of pheasants hung at 5, 10 and 15 degrees C     

E M Barnes  G C Mead  N M Griffiths 《British poultry science》1973,14(3):229-240

Pheasants hung for 9 d at 10 °G were found to be more acceptable than those hung for 4 d at 15 °G or for 18 d at 5 °G. The birds stored at 15 °G were tough by comparison with those held for longer at the lower temperatures and the clostridia, including Clostridium welchii, increased considerably in the intestines during the storage period. Microbial growth in the muscle tissue was generally found to occur only in birds in which the gut had been perforated by shot. There is an indication that 9 d at 10 °C produced a more “ gamey “ bird than 18 d at 5 °G or 4 d at 15 °G, but the most “ gamey “ birds, independent of temperature, were those in which the muscle was damaged by shot.  相似文献   

Pathogenesis and pathologic changes of experimentally induced listeriosis in newborn pigs   总被引：1，自引：0，他引：1  

R H Busch  D M Barnes  J H Sautter 《American journal of veterinary research》1971,32(9):1313-1320

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Pseudoparasitism of broiler chicks by mites of the family Uropodidae, genus Fuscuropoda     

D V Rives  H J Barnes 《Avian diseases》1988,32(3):567-569

Seven 6-day-old broiler chicks were presented dead and heavily infested with ectoparasites. Tentatively identified as Argas ticks, the parasites were later determined to be non-parasitic mites of the family Uropodidae, genus Fuscuropoda.  相似文献