Attempts at sex determination on 6- and 7- day old cattle embyros     

L A Moustafa  J Hahn  R Roselius 《Berliner und Münchener tier?rztliche Wochenschrift》1978,91(12):236-238

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Cultural demonstration of Campylobacter fetus subspecies fetus in preputial rinsing samples from insemination and breeding bulls     

H Stadtfeld  E Nitzschke  W Hahn  A Konz 《Berliner und Münchener tier?rztliche Wochenschrift》1982,95(20):393-397

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Lactic acidosis: a factor associated with equine laminitis   总被引：4，自引：0，他引：4  

H E Garner  D P Hutcheson  J R Coffman  A W Hahn  C Salem 《Journal of animal science》1977,45(5):1037-1041

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Serving capacity of crossbred yearling beef bulls. II. Summer grazing activity and body temperature patterns during average and heavy mating loads at pasture     

G W Boyd  D D Lunstra  L R Corah  R C Cochran  G L Hahn 《Journal of animal science》1989,67(1):72-79

Ten low (LSC) and 10 high (HSC) serving capacity yearling bulls were exposed individually to 25 naturally cyclic (N) cows for 3 d (average mating load) and subsequently to 9 estrus-synchronized (S) cows for 1 d (heavy mating load) in a randomized complete block design consisting of 10, 4-d blocks. Bulls were fitted with vibracorders and temperature acquisition modules to record grazing activity and body temperature (BT), respectively. During the N cow treatment, LSC bulls had fewer (P less than .05) services per cow and a higher mount to service ratio than HSC bulls, and LSC bulls tended (P = .12) to graze less total time than HSC bulls (7.8 vs 9.0 h/d, respectively). However, both groups of bulls exhibited similar diurnal grazing patterns with two major daily grazing periods; the first (0400 to 1300) peaked early in the morning (0600) and the second (1700 to 2200) occurred in late afternoon and evening. During the S cow treatment, LSC and HSC bulls did not differ (P = .60) in grazing time or pattern, but similar mating activity was exhibited by both SC groups while exposed to S cows. Bulls grazed little during the hottest part of the day (1300 to 1700), and LSC and HSC bulls spent only 2.2 and 2.4 h, respectively, grazing during dark, cooler periods near midnight. Body temperature did not differ between SC groups and averaged 39.3 degrees C during N cow treatment and 39.4 degrees C during S cow treatment. Body temperature had a distinct, monophasic diurnal pattern in bulls exposed to an average mating load.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

Geklontes Kalb in Neustadt geboren     

J. Todorov  T. Todorova  U. Zimmermann  W.M. Arnold  C. Leiding  R. Hahn  J. Hahn 《Reproduction in domestic animals》1992,27(5):307-309

Am 27.8.1992 wurde beim Besamungsverein Neustadt (BVN) in Neustadt a.d. Aisch ein geklontes Fleckviehkalb geboren. Die Identität der Abstammung konnte eindeutig gesichert werden. Der erfolgreiche Kerntransfer in einem Versuchsprogramm soll belegen, daβ sich nach der Fusion einer Blastomere aus einem Spenderembryo mit einer in vitro gereiften und enukleierten Empfängeroozyte ein Embryo entwickeln kann, der nach Transfer auf ein Empfängertier zur Geburt eines gesunden Kalbes führt.
Contents: A cloned calf was born in Neustadt ad. Aisch
A cloned "Fleckvieh" calf was born at the Al-Association Neustadt (BVN) in Neustadt a.d. Aisch on August, 27, 1992. The identity of the parentage could be verified undoubtedly. The successful nuclear transfer in an experimental program showed that the fusion of a blastomere from a donor embryo with an in vitro matured and enucleated recipient oocyte led to the development of an embryo, and after transfer to a synchronous recipient to the birth of a healthy calf.  相似文献   

Role of blackflies in the epidemiology of Potomac horse fever     

N E Hahn  B D Perry  R M Rice  J W Hansen  E C Turner 《The Veterinary record》1989,125(10):273-274

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Characterization of porcine xenoreactive cytotoxic T lymphocytes.     

D M Dunham  E C Hahn 《Veterinary immunology and immunopathology》1992,34(3-4):209-220

Cytotoxic T lymphocytes (CTL) against mouse P815 cells were detected after stimulation of porcine peripheral blood mononuclear cells (PBMC) with irradiated Balb/c splenocytes. In vivo priming prior to in vitro stimulation slightly enhanced CTL activity, but lysis of targets was undetectable from lymphocytes from non-immune or immune animals that were not cultured with mouse splenocytes. After primary culture with Balb/c (H-2d) splenocytes, specific killing of P815 (H-2d) targets and not L929 (H-2k) targets indicated that recognition was specific for the H-2 locus. Similarly, CTL primed by mouse cells from either of two congenic strains recognized targets with alleles homologous to the stimulating cells. The anti-murine CTL was confirmed to be a CD8+ T cell based on studies using specific monoclonal antibodies to the porcine CD4 or CD8 cells. The cells responsible for the cytotoxicity of P815 targets lacked the characteristics of non-specific NK cells because (1) naive PBMC were unable to lyse NK targets (K562 cells) during the 4 h cytotoxic assay and (2) CTL killing of P815 targets increased with time after primary stimulation, whereas killing of K562 cells remained low at all times. These results suggest that porcine CTL can be readily generated against the xenogeneic mouse major histocompatibility complex.  相似文献   

Cisplatin Therapy in 41 Dogs With Malignant Tumors   总被引：3，自引：0，他引：3  

Deborah W. Knapp DVM    Ralph C. Richardson DVM    Patty L. Bonney BS  RVT  Kevin Hahn DVM 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》1988,2(1):41-46

Forty-one dogs with a variety of histopathologically diagnosed, measurable tumors were treated with cisplatin (cis-diamminedichloroplatinum, Platinol, Bristol Laboratories, Syracuse, NY 13221-4755) as a single agent at a dosage of 60 mg/m2 given intravenously at 3-week intervals. In an attempt to avoid renal toxicity of cisplatin, saline diuresis was induced and maintained for 4 hours before and 2 hours following cisplatin administration. The dogs received one to ten doses of cisplatin. To determine response to therapy and to monitor toxicity of the drug, the dogs were evaluated with physical examinations including tumor measurements, radiography, complete blood counts, platelet counts, urinalyses, serum urea nitrogen concentrations, and serum creatinine concentrations. An overall response rate of 19% was observed. Complete remission occurred in one of 11 dogs with squamous cell carcinomas and one of one dog with a mediastinal undifferentiated carcinoma. Partial remissions were documented in one of 11 dogs with squamous cell carcinomas, two of three dogs with metastatic osteosarcomas, one of three dogs with nasal adenocarcinomas, and one of one dog with a thyroid adenocarcinoma. Toxic side effects were primarily gastrointestinal in nature, with vomiting occurring 1-6 hours after cisplatin administration in 27 of 41 dogs. Severe anorexia occurred in three dogs, and hemorrhagic diarrhea was observed in one dog. One dog developed grand mal seizures and died 3 hours following therapy. Granulocytopenia was documented in six dogs, and thrombocytopenia was observed in four dogs. One dog showed an increase in serum urea nitrogen and creatinine concentrations, but this patient had known pre-existing renal disease.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

Thyroid neoplasms in a colony of beagle dogs     

P J Haley  F F Hahn  B A Muggenburg  W C Griffith 《Veterinary pathology》1989,26(5):438-441

The histologic, clinicopathologic, and epidemiologic features of spontaneous thyroid neoplasms were evaluated in a control population of Beagle dogs. The mean age of thyroid tumor-bearing dogs (16.2 years) as significantly higher than non-tumor-bearing dogs (13.6 years). Thirteen benign and 18 malignant tumors were identified, with the incidence of both tumors increasing rapidly near the mean age of 16.2 years for tumor-bearing dogs. The age-specific incidence of tumors was 1.1% per year at 8 to 12 years, increasing to 4.0% per year by 12 to 15 years and 67% over 17 years of age. Numbers of malignant tumors were greater than benign tumors at an earlier age. Approximately 44% of the malignant tumors metastasized but only 22% resulted in death of the dog. There was no difference in tumor incidence when compared according to sex, if total tumor numbers were considered or if tumors were separated into benign and malignant categories. The age at death of tumor-bearing dogs was not increased significantly by the surgical resection of the thyroid tumors. Of dogs with thyroid tumors, 15% had clinical diagnoses of hypothyroidism, and no dogs with thyroid tumors had diagnoses of hyperthyroidism.  相似文献   

Superovulation beim Rind: Hormonprofile bei Stimulation mit Serum-gonadotropin (PMSG) bzw. hypophysärem FSH*)     

D. Von Schams  Ch. Menzer  E. Schallenberger  B. Hoffmann  A. Prokopp  B. Hahn  R. Hahn 《Reproduction in domestic animals》1979,14(1):11-25

Contents: Superovulation in cattle: Hormonal profdes during superovulation with PMSG or pituitary FSH.: Hormonal profiles for LH, FSH, PMSG, progesterone in peripheral blood and oestrogens in urine during superovulation with PMSG (1500–3100 IU i. m.) or pituitary porcine FSH (5 mg i.m. 2 times daily for 5 days) were evaluated radioimmunologicaly. Two days after the begin of treatment luteolysis was induced by means of 0.5 mg Estrumat® i. m. The experiments were performed with 14 heifers and 2 cows. Blood samples were taken in 6 or 12 h intervals. Preovulatory LH and FSH peaks occurred coinciding with the onset o f oestrus in good responding animals instead of a few hours later, as in weakly responding animals or during normal oestrous cycle. PMSG could be still measured in peripheral blood 10 days after application. Preovulatory gonadotropin peaks are preceded in good responding animals by clear oestrogen peaks contrary t o weak responding ones. Progesterone concentrations of good responding animals increase faster after the preouulatory LH peak and reach higher absolute values compared t o bad responding ones or during normal oestrous cycle. Furthermore there was a clear difference in progesterone values between both stimulation methods. Progesterone concentrations after induction of superovulation with PMSG are significantly higher f o r about the same number of corpora lutea as after stimulation with pituitary FSH. For judgement of the success of stimulation the determination of progesterone can be considered as parameter. From the hormonal profiles no conclusion can be drawn why some animals don't respond to the stimulation.  相似文献