Conversion of Cortisone to Cortisol and Prostaglandin F2α Production by the Reproductive Tract of Cows at the Late Luteal Stage In Vivo     

HT Duong  DJ Skarzynski  KK Piotrowska‐Tomala  MM Bah  K Jankowska  P Warmowski  K Łukasik  K Okuda  TJ Acosta 《Reproduction in domestic animals》2012,47(6):939-945

Previous in vitro studies demonstrated that bovine endometrium has the capacity to convert inactive cortisone to biologically active cortisol (Cr) and that Cr inhibits cytokine‐stimulated prostaglandin F_2α (PGF) production. This study was carried out to test the hypothesis that bovine reproductive tract has the capacity to convert cortisone to Cr in vivo and to evaluate the effects of intravaginal application of exogenous cortisone on uterine PGF secretion during the late luteal stage. The temporal relationships between PGF and Cr levels in uterine plasma were also determined. Catheters were inserted into jugular vein (JV), uterine vein (UV), vena cava caudalis (VCC) and aorta abdominalis (AA) of six cows on Day 15 of the oestrous cycle (ovulation = Day 0) for frequent blood collection. On Day 16, the cows were divided randomly into two groups and infused intravaginally with vaseline gel (10 ml; control; n = 3) or cortisone dissolved in vaseline gel (100 mg; n = 3). Blood samples were collected at ?2, ?1, ?0.5, 0, 0.5, 1, 1.5, 2, 3, 4, 5 and 6 h after treatments (0 h). Intravaginal application of cortisone increased plasma concentrations of Cr between 0.5 and 1.5 h in UV, at 0.5 h in VCC, at 1 h in JV and at 1.5 h in AA. The plasma concentrations of PGF in UV and of PGF metabolite in JV were greater at 0.5 and 1 h in the cortisone‐treated animals than in control animals. The levels of PGF in UV blood plasma decreased after Cr reached its highest levels. The overall findings suggest that the female reproductive tract has the capacity to convert cortisone to Cr in vivo. Based on the temporal changes of PGF and Cr levels in the uterine plasma, a biphasic response in PGF secretion was found to be associated to the Cr increase induced by the cortisone treatment at the late luteal stage in non‐pregnant cows.  相似文献   

Germany/Australia Index of Sperm Sex Sortability in Elephants and Rhinoceros     

B Behr  D Rath  TB Hildebrandt  F Goeritz  S Blottner  TJ Portas  BR Bryant  B Sieg  A Knieriem  SP de Graaf  WMC Maxwell  R Hermes 《Reproduction in domestic animals》2009,44(2):273-277

Flow cytometric sexing of spermatozoa followed by application in artificial insemination or in vitro fertilization provides a unique opportunity to predetermine the sex of offspring and might enhance the conservation management of endangered species in captivity such as the elephant and rhinoceros. To obtain an indication of the sortability of spermatozoa from these species, the relative DNA differences between X and Y chromosome bearing spermatozoa (fresh, frozen thawed, epididymal) from three rhinoceros species [white ( Ceratotherium simum ), black ( Diceros bicornis ), Indian ( Rhinoceros unicornis )] and both elephant species, the Asian and the African elephant ( Elephas maximus, Loxodonta Africana ), were determined through separation of spermatozoa into X and Y chromosome bearing populations, using a modified high speed flow cytometer. The head profile areas of spermatozoa from all five species were measured using light microscopy. By multiplying the relative DNA differences and the head profile areas, the sperm sorting indices were calculated to be 47, 48 and 51 for white, black and Indian rhinoceros respectively. The calculated sorting index for the Asian elephant was 66. In the African elephant, we determined the highest sorting index of 76. These results indicate the practicability of flow cytometric sex sorting of spermatozoa from the tested rhinoceros species and both elephant species. The lower sorting indices in rhinos indicate that sex sorting of spermatozoa from the rhinoceros will be more challenging than in elephants.  相似文献   

Longitudinal study of career plans and directions of veterinary students and recent graduates during the first five years after graduation   总被引：2，自引：1，他引：1  

TJ HEATH 《Australian veterinary journal》1998,76(3):181-186

Objectives To determine the patterns of work undertaken by veterinarians during the first 5 years after graduation, and to study the background to career decisions. Design Longitudinal study. Population Veterinarians (119) who started the veterinary course at The University of Queensland in 1985 and 1986, and who responded to a mailed questionnaire 5 years after they graduated. Procedure Questionnaires were completed in the first and fifth year of the veterinary course, and in the second and after the fifth year after graduation. The data were coded numerically and analysed using the SAS System for Windows. Results Most respondents (61%) planned to work in mixed practice and 61% entered mixed practice initially, but only 39% of these (26% of the total) remained in mixed practice after 5 years. Those who had grown up on a farm which derived primary income from animals were more likely to enter mixed practice, but half of this group had left mixed practice after 5 years. Most decisions to change career direction involved a move away from negative factors including inadequate private time and/or rewards, issues involving other people including the practice principal and sometimes clients, or aspects of the work itself. However, some cited positive reasons, including opportunities to learn, to help others or to travel. There were no significant differences between males and females in the numbers entering mixed practice or leaving it, or entering small animal practice, or in attitudes to many issues involving veterinarians. However, more females than males found their remuneration too small, and females did receive significantly smaller incomes than males. Conclusions Most graduating veterinarians, especially those from farms with animals, seek to enter mixed practice initially. Negative experiences are mainly responsible for moves to small animal practice. Gender does not affect the distribution of young veterinarians between mixed and small animal practice.  相似文献   

Biological characterisation of Australian isolates of chicken anaemia agent   总被引：1，自引：0，他引：1  

TJ CONNOR  F. McNEILLY  GA FIRTH†  MS McNULTY† 《Australian veterinary journal》1991,68(6):199-201

Three Australian isolates of chicken anaemia agent (CAA) resisted treatment at 70 degrees C for 5 min and chloroform treatment. Although minor antigenic differences were detected using monoclonal antibodies to CAA, the Australian isolates were indistinguishable from the reference Cux-1 and Gifu-1 isolates in cross-immunofluorescence and cross-neutralisation tests employing polyclonal chicken antiserums. The Australian viruses were pathogenic for intramuscularly inoculated 1-day-old SPF chicks, but were less pathogenic for 7-day-old chicks. Thus the Australian isolates of CAA did not differ significantly in these properties from previously characterised CAA isolates from other continents.  相似文献   

Freezing resistance in some Antarctic fishes   总被引：19，自引：0，他引：19  

A L DeVries  D E Wohlschlag 《Science (New York, N.Y.)》1969,163(871):1073-1075

Measurements of serum freezing points in three Antarctic marine fishes indicated that they do not freeze in the -1.87 degrees C seawater because their blood is isosmotic to seawater. Concentrations of sodium chloride, urea, and free amino acids in the serum accounted for only half of the freezing-point depression of the serum. A protein containing carbohydrate was isolated which accounted for 30 percent of the freezing-point depression of the serum.  相似文献   

Temperature tolerance of some Antarctic fishes   总被引：22，自引：0，他引：22  

G N Somero  A L DeVries 《Science (New York, N.Y.)》1967,156(772):257-258

Three species of Antarctic fishes which live in constantly near-freezing waters have a markedly low upper-lethal temperature of 6 degrees C ; this is the lowest upper-lethal temperature reported for any organism. The fishes survive supercooling to -2.5 degrees C. Data on brain metabolism in vitro support the hypothesis that the central nervous system is a primary site of thermal injury.  相似文献   

Diagnostic utility of cerebrospinal fluid analysis in dogs with suspected idiopathic epilepsy     

SE Gilbert  TJ Cardy  S Bertram  F Taylor‐Brown 《Australian veterinary journal》2021,99(1-2):1-5

  相似文献   

Poultry Diseases     

TJ BAGUST 《Australian veterinary journal》2002,80(12):757-757

  相似文献   

Susceptibility to antimicrobials of mastitis‐causing Staphylococcus aureus,Streptococcus uberis and Str. dysgalactiae from New Zealand and the USA as assessed by the disk diffusion test          下载免费PDF全文

KR Petrovski  A Grinberg  NB Williamson  ME Abdalla  N Lopez‐Villalobos  TJ Parkinson  IG Tucker  P Rapnicki 《Australian veterinary journal》2015,93(7):227-233

  相似文献   

Headspace gas chromatographic method for determination of methyl bromide in food ingredients     

J W DeVries  J M Broge  J P Schroeder  R H Bowers  P A Larson  N M Burns 《Journal of the Association of Official Analytical Chemists》1985,68(6):1112-1116

A headspace gas chromatographic (GC) method, which can be automated, has been developed for determination of methyl bromide. This method has been applied to wheat, flour, cocoa, and peanuts. Samples to be analyzed are placed in headspace sample vials, water is added, and the vials are sealed with Teflon-lined septa. After an appropriate equilibration time at 32 degrees C, the samples are analyzed within 10 h. A sample of the headspace is withdrawn and analyzed on a gas chromatograph equipped with an electron capture detector (ECD). Methyl bromide levels were quantitated by comparison of peak area with a standard. The standard was generated by adding a known amount of methyl bromide to a portion of the matrix being analyzed and which was known to be methyl bromide free. The detection limit of the method was 0.4 ppb. The coefficient of variation (CV) was 6.5% for wheat, 8.3% for flour, 3.3% for cocoa, and 11.6% for peanuts.  相似文献