摘要:

Inhalt:Beschrieben wird eine einfache Methode zur Isolierung von Präantralfollikeln aus Eierstöcken des Rindes. Nach einer dosierten Mazerierung der Rindenzone und anschlieβenden physikalischen Zellseparationsverfahren konnten aus einem Ovar durchschnittlich 300 Präanhalfollikel gewonnen werden, die anhand des Durchmessers (40–100μm) und der Zahl der Follikelepithelschichten als Primär‐ (einschichtiges Epithel) und Sekundärfollikel (mehrschichtiges Epithel) charakterisi

ISSN:0936-6768    

DOI:10.1111/j.1439-0531.1991.tb01542.x

出版商:Blackwell Publishing Ltd    

年代:1991

数据来源: WILEY

摘要:

Contents:Some aspects of the bovine uterine defense mechanisms were evaluated over two successive estrous cycles in five adult nonpregnant Friesian cows. Uterine flushings and blood samples were taken from each cow during the estrus and diestrus phases of each estrous cycle. A significant higher percentage of Candida albicans (C. albicans) were phagocytosed (P<0.01) and killed (P<0.05) by blood neutrophils during estrus than during diestrus. N‐acetyl‐β‐D‐glucosaminidase activity of uterine flushings, blood neutrophil alkaline phosphatase activity scores, and serum progesterone concentrations during diestrus increased significantly (P<0.01) compared to those at estrus. Mean total blood leucocyte and monocyte counts increased significantly (P<0.05) during estrus compared to diestrus.It is concluded, that the different hormonal status has at each stage of the estrous cycle a definite effect on uterine resistance against bacterial infection and a fall in serum progesterone concentrations is associated with an increased ability of blood neutrophils to phagocytose and kill C.

ISSN:0936-6768    

DOI:10.1111/j.1439-0531.1991.tb01543.x

出版商:Blackwell Publishing Ltd    

年代:1991

数据来源: WILEY

摘要:

Contents:The addition of the antibiotic combinations penicillin and streptomycin on the one hand, and gentamicin, tylosin, lincomycin, and spectinomycin on the other hand, to a Tris egg‐yolk extender for bovine semen was investigated on the basis of insemination results. The nonreturn rates, calculated separately for heifers (n = 2108) and cows (n = 8930), showed no significant differences between the two combinations of antibiotic

ISSN:0936-6768    

DOI:10.1111/j.1439-0531.1991.tb01544.x

出版商:Blackwell Publishing Ltd    

年代:1991

数据来源: WILEY

摘要:

Contents:Eighty‐five animals were used to develop an embryo transfer programme including a study on how oestrus synchronization influenced the ovulation rate. The animals, both ewes and ewe lambs, were divided into three groups: donors, recipients and controls. Oestrus was synchronized in donors and recipients by the use of progesterone‐impregnated vaginal pessaries. The donors also received one injection of 600 IU PMSG. Samples for microbiological investigation of the vaginal flora were taken in connection with synchronization. The ovulation rate was determined by laparoscopy in the control animals and by laparotomy in the donors and recipients. The embryos were surgically recovered from the donors by flushing of the uterine horns seven days after pessary removal. The embryos were classified according to developmental stage and quality. At transfer each recipient received 2–4 embryos (moruhs or blastocysts) by a surgical method. A ± 1 day asynchrony in oestrus between donors and recipients was tolerated. All synchronized animals came into oestrus within 2.5 days after pessary removal. The interval was shorter if the animals had been injected with PMSG. The largest number of ovulations occuwed in the synchronized and PMSG‐treated animals (mean 4.5 ± 2.1). Synchronized animals that did not receive PMSG had almost the same ovulation rate as the control animals (2.6 ± 0.9 versus 2.5 ± 0.7). The pessary treatment influenced the bacterial flora of the vagina. The number of ewes with bacterial growth in the vagina increased. The number of isolated organisms also increased. The embryo recovery rate was 80.8% and 3.7 ± 2.7 ovas was recovered on average. Eighty‐eight percent of all donors yielded transferable embryos. Morulas and blastocysts comprised 84.4% of the recovered oocytes/embryos. Only 5.2% of these were of poor quality. Of the transferred embryos, 65.1% developed into lambs and 91.3% of the recipients lambed. The ewe lambs were as suitable as donors and recipients as

ISSN:0936-6768    

DOI:10.1111/j.1439-0531.1991.tb01545.x

出版商:Blackwell Publishing Ltd    

年代:1991

数据来源: WILEY

摘要:

Contents:Flow cytometric sorting of X and Y chromosome‐bearing sperm into separate populations, followed by surgical insemination into the isthmus of the oviduct of mature gilts, produced litters with phenotypic sex ratios skewed in the direction of male or female according to the predicted sex of the sperm population inseminated. The skewing of the sex ratio of the offspring was predicted from flow cytometric DNA reanalysis of flow sorted sperm populations. Gilts inseminated with intact, viable flow‐sorted X‐bearing sperm produced litters of off spring that were 74% female (P<.01). Gilts inseminated with intact, viable flow‐sorted Y‐bearing sperm gave off spring that were 68% male (P<.04). These results validate the use of DNA as a marker for pre‐selecting the sex of offspring when used in conjunction with flow cytometric sorti

ISSN:0936-6768    

DOI:10.1111/j.1439-0531.1991.tb01546.x

出版商:Blackwell Publishing Ltd    

年代:1991

数据来源: WILEY

ISSN:0936-6768    

DOI:10.1111/j.1439-0531.1991.tb01547.x

出版商:Blackwell Publishing Ltd    

年代:1991

数据来源: WILEY

摘要:

Abstract:Pregnancy detection in cows by pulse mode ultrasoundTwo commercially available pulse mode ultrasound instruments for pregnancy detection in cows were examined by testing 50 pregnant Friesian cows twice weekly. Absolutely reliable results were obtained after d 181 (“Cow‐Tone”) and d 221 of pregnancy (Preg‐Alert 7 respectively. A newly constructed instrument (“HK‐Rheintechnik”) operating with greater wavelength (0,7 MHz) was tested in a similar fashion on 62 pregnant cows. Zt produced absolutely reliable results from d 135 of pregnancy on, i.e. 46 days sooner than the best of the commercial instr

ISSN:0936-6768    

DOI:10.1111/j.1439-0531.1991.tb01548.x

出版商:Blackwell Publishing Ltd    

年代:1991

数据来源: WILEY

ISSN:0936-6768    

DOI:10.1111/j.1439-0531.1991.tb01549.x

出版商:Blackwell Publishing Ltd    

年代:1991

数据来源: WILEY

ISSN:0936-6768    

DOI:10.1111/j.1439-0531.1991.tb01550.x

出版商:Blackwell Publishing Ltd    

年代:1991

数据来源: WILEY