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As a contribution to knowledge of anoestrus in heifers, a case of testicular feminisation in a Friesian heifer is reported. This is the first case of this unusual intersex form in German breeds of cattle. 2. The genital syndrome “testicular feminisation” originates in genotypically male animals with foetal testicular insufficiency resulting in diminished or absent androgen production. For this reason, despite the male karyotype, phenotypically female individuals develop with normal female external genitalia, but lacking a uterus and having a short vagina. The male internal organs are also absent, apart from the large intra-abdominal testes. 3. Testicular parenchyma and tubular epithelium are arrested in a state of embryonic development, with severe degeneration of the tubular epithelium which do not contain cells at more developed stages of spermiogenesis. 4. Testicular feminisation is genetically conditioned and is due to a recessive, sex-linked gene which is transmitted by female animals. The frequency of occurrence of this gene and the incidence of the defect in the population appear to be very low.  相似文献   
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Ohne Zusammenfassung Mit 6 Abbildungen (Zeichnungen:R. Kliefoth)  相似文献   
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The aim of this study was to evaluate the reproductive performance of three parities of gilts treated or not treated with gonadotropin to induce puberty. Sixty gilts received 600 IU of equine chorionic gonadotropin (eCG) followed by 2.5 mg of porcine luteinizing hormone (LH) 72 h later. Fifty‐nine other gilts were exposed only to a mature boar for 15 min twice daily. Artificial insemination (AI) was performed at 0, 12 and 24 h after the detection of oestrus, and gestation was confirmed by ultrasound after 35 days. Sows were inseminated at the first post‐weaning oestrus. The total numbers of piglets born, piglets born alive, stillborn, mummified foetuses, as well as pregnancy and farrowing rates were evaluated for each of the three parities. Culling rates, farrowing intervals and weaning‐to‐oestrous intervals (WEI) were also analysed. Mean age at puberty and oestrous manifestation were not significantly different between treatments (p = 0.0639; 179.20 ± 17.52 compared with 173.96 ± 16.94, 91.66% compared with 94.92%) across the experimental period. However, females that underwent puberty induction showed modest increases both in the number of total pigs born and in the number of piglets born alive. In conclusion, puberty induction through exogenous gonadotropin administration in field conditions did not induce a more concentrated first oestrous manifestation, but trended to a modest increase in the number of pigs born alive in the first parity and a reduced culling rate during the first gestation.  相似文献   
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Amplification of the 16S rRNA gene from a blood sample obtained from a dog in southeastern Brazil was used to confirm a naturally acquired Ehrlichia (E.) canis infection. Following isolation and culturing of the new bacterial strain called Uberlândia, partial sequences of the dsb and p28 genes were obtained. The dsb partial sequence of the novel strain was 100% similar to dsb gene sequences of E. canis obtained from different geographic areas around the world. Conversely, the p28 partial sequence for the E. canis Uberlândia strain differed at several nucleotides from other sequences available in GenBank. To confirm the antigenic profile of the Uberlândia strain, an indirect immunofluorescence assay against E. canis antigens was performed using dog sera collected from two different areas in Brazil (Uberlândia and São Paulo). The results suggest that both antigens were able to identify animals seropositive for E. canis in Brazil since these Brazilian strains appear to be highly conserved.  相似文献   
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A new antiepileptic and anxiolytic drug, ELB138, was evaluated in a clinical pilot study in dogs with newly diagnosed or chronic idiopathic epilepsy. The purpose was to verify clinically the anticonvulsant effectiveness of this substance, which had already been demonstrated experimentally. Data from 29 dogs treated with ELB138 were compared with results obtained retrospectively from 82 dogs treated with conventional antiepileptic medication. The reduction in seizure frequency using ELB138 in dogs with newly diagnosed idiopathic epilepsy was comparable to the reduction in dogs treated either with phenobarbital or primidone. In dogs with chronic epilepsy and add-on therapy with either ELB138 or potassium bromide, such supplementation reduced the seizure frequency and the duration and severity of seizures. The most obvious difference between ELB138 treatment and conventional medications became clear in the evaluation of side effects, which in those dogs treated with ELB138 were rare, and consisted mostly of transient polyphagia. This pilot study confirmed that ELB138 has a potent anticonvulsant effect in dogs with idiopathic epilepsy. These results will form the basis for a multicentre, blinded study.  相似文献   
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Objective – To compare the placement feasibility and amount of bone trauma induced by 3 intraosseous (IO) access techniques in cats: an automatic impact penetration device (A), an automatic rotary insertion device (B), and a manual IO needle (C). Design – Prospective ex vivo study. Setting – University. Animals – Eighteen adult mixed breed feline cadavers. Interventions – Cadavers provided 72 total IO insertion locations divided equally between the right and left humerus and tibia. The 3 IO techniques were randomly allocated to these locations. Time to successful insertion, ease of insertion, and success rate were recorded. Each insertion site was analyzed for the number of bone fragments and defect diameter by computed tomography. Measurements and Main Results – Device B had lower time of insertion (P=0.01) compared with devices A and C. Device B had better ease of insertion scores (P<0.01) compared with devices A and C. No differences were detected between insertion sites (tibia versus humerus). No differences in the number of bone fragments, defect diameter, or success rate were detected among devices (P=0.06, 0.31, and 0.14, respectively). Conclusions – All 3 IO access methods evaluated yield acceptable results. Device B is significantly faster and easier to place in cat cadavers when compared with other methods.  相似文献   
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SUMMARY The passive blomechanical property of oesophageal compliance (OC) was measured in 8 naturally occurring cases of canine megaoesophagus, 8 matched control and 7 vagotomised control dogs. Of the 8 dogs with megaoesophagus, 6 had congenital Idiopathic megaoesophagus and 2 had secondary megaoesophagus attributable to generalised skeletal muscle disease. Stepwise distension of the whole oesophagus was employed for measurement of OC at the 4.0 and 8.0 mL/kg Injected volume steps within the control volume range (0 to 12.0 mL/kg). At both Injected volume steps OC was higher In megaoesophagus dogs than in either matched control or vagotomised control dogs (P / 0.01 In both cases), and no significant difference was observed In OC between matched control and vagotomised control dogs. No correlation was demonstrated between OC and the estimated duration of clinical signs of dogs with megaoesophagus. These findings suggest that In most cases of canine megaoesophagus the viscoelastic properties of the oesophageal wall are significantly altered, that In such cases the disorder is unlikely to be purely dynamic and that processes other than the duration of oesophageal dilatation are responsible for the alteration in oesophageal wall blomechanical properties. The relevance of these findings to current concepts on pathophysiological mechanisms underlying the evolution and resolution of various forms of canine megaoesophagus Is discussed.  相似文献   
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Inhalt: Auf Grand fünfjähriger systematischer Registrierung der angeborenen Anomalien bei allen Rinderrassen des Landes Hessen wird festgestellt, daß unter den Nachkommen von Besamungsbullen prozentual nicht mehr mißgebildete Kälber auftreten als bei den Nachkommen von Bullen, die im Natursprung eingesetzt waren. Das breitgestreute Spektrum der Organdefekte umfaßt etwa 43 Mißbildungskategorien und Mißbildungssyndrome; das Zentralnervensystem ist mit ca. 25% am häufigsten beteiligt. Die Aufstellung von "Teratograrnnaen" der Nachkommengruppen ermöglicht die verhältnismäßig frühzeitige Testung von Jungbullen, die für den Einsatz in der KB vorgesehen sind. Da zwischen Nachkommenzahl (Einsatzdauer) der einzelnen Bullen und Mißbildungshäufigkeit bei ihren Nachkommen positive Beziehungen bestehen, bedeuten signifikante Abweichungen von diesen "Normalwerten" der Mißbildungsfrequenzen innerhalb der Nachkommengrößenklassen besondere genetische Situationen der Väter. Diese können in der Anlage für besondere pathologische Merkmale bestehen oder sich in zufallsbedingten embryonalen Entwicklungs-storungen mannigfacher Art als Folge einer individuellen Genomlabilität der Embryonen äußern .  相似文献   
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