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Categories of infertility are defined according to semen characteristics. Assessment of daily sperm output and carefully planned matings to determine the extent of infertility and to manage insemination to maximize fertility are described. The contributions of baseline laboratory data, evaluation of reproductive hormones, and testicular biopsy in determining the causes of infertility are discussed. Treatments of infertility secondary to systemic disease, infertility caused by accessory gland infections, and infertility associated with abnormal gonadotropin concentrations are reviewed. 相似文献
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M M Sommer V N Meyers-Wallen 《Journal of the American Veterinary Medical Association》1991,198(3):435-438
XX True hermaphroditism was identified in a 5-month-old German Shorthaired Pointer with a large clitoris. The gonads were situated caudal to the kidneys at the cranial tips of the uterine horns, and were composed mainly of seminiferous tubules and interstitial cells and had ovarian follicles in the cortices. Each gonad had efferent tubules, a pampiniform plexus, fimbriae, and a uterine tube. The uterus was positioned normally in the abdomen and had no gross or histologic abnormalities. Giemsa-banded karyotypes revealed a normal female 78,XX chromosomal complement with no structural abnormalities. 相似文献
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Presumptive Sry-negative XX sex reversal in a llama with multiple congenital anomalies. 总被引：1，自引：0，他引：1
M L Drew V N Meyers-Wallen G M Acland C L Guyer D N Steinheimer 《Journal of the American Veterinary Medical Association》1999,215(8):1134-1139
Multiple congenital abnormalities of the external genitalia consistent with XX sex reversal were detected in a juvenile llama. The llama had a typical female karyotype (74, XX) and did not have a Y chromosome, but a minute chromosome was detected. To determine whether a piece of Y chromosome containing the Sry gene might be located in a small translocation, DNA analysis by polymerase chain reaction was performed; the Sry gene was not detected. Histologic examination revealed ovarian tissue, whereas testicular tissue was not found. External genitalia were partially masculinized, indicating that the urogenital sinus, genital tubercle, and genital swellings had been exposed to androgens during development, although the dam had not received exogenous androgens. Testicular tissue in the ovaries may have been undetected or had regressed prior to birth, as has been reported in sex reversal in mice. 相似文献
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M. KROSSH A VN J. O. BJORGUM J. KRANE E. STEINNES 《European Journal of Soil Science》1990,41(3):371-377
Eleven samples of terrestrial humus from different vegetational backgrounds were examined with solid-state 13C NMR using cross-polarization and magic-angle spinning (CP-MAS). In addition, all the samples were run with a dipolar dephasing pulse sequence for non-quarternary carbon suppression (NQS). The humus samples all appeared to contain small amounts of aromatic substances and larger amounts of aliphatic compounds. Most of the samples contained considerable amounts of hydroxyl groups and acetals, which originate mainly from carbohydrates. No correlations were found between vegetational background and chemical structure. 相似文献
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V N Meyers-Wallen M H Goldschmidt G L Flickinger 《Journal of the American Veterinary Medical Association》1986,189(12):1557-1561
Immediate and long-term outcomes of prostaglandin F2 alpha treatment for canine pyometra were studied in 10 bitches. Examination of pretreatment uterine biopsy specimens, taken for histopathologic diagnosis and classification of disease severity, revealed either type III or IV pyometra. Dinoprost tromethamine (0.25 or 0.5 mg/kg of body weight, SC) was given once daily for 3 days. Bitches were bred at the first posttreatment estrus and monitored for a minimum of one year. When pure cultures of Escherichia coli (n = 3) or Staphylococcus aureus (n = 1) were obtained from the vagina, these bacteria also were found in the uterus. Pretreatment WBC counts often did not reflect the severity of histopathologic findings in the uterus, but posttreatment WBC counts were useful in monitoring response to treatment. Four bitches produced a litter within one year of treatment. Four bitches (40%) had recurrence of pyometra within one year of treatment, and these same bitches had another recurrence after an additional prostaglandin treatment. Three additional bitches had a recurrence by 27 months after therapy, establishing a total recurrence rate of 77% (7/9). Results suggested that subclinical disease may persist after treatment, with clinical recurrence during diestrus. Despite the high recurrence rate, it was concluded that this treatment is a practical treatment for canine pyometra when reproduction is desired. 相似文献
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A E Yeager H O Mohammed V Meyers-Wallen L Vannerson P W Concannon 《American journal of veterinary research》1992,53(3):342-351
Serial ultrasonographic examinations were performed on 8 Beagle bitches from 20 to 60 days pregnant to determine time of first detection, appearance, and sizes of selected features of pregnancy. Gestation was timed from the day of the preovulatory luteinizing hormone surge. Findings related to gestational age were consistent among bitches. Gestational ages at earliest detection of the following features were: chorionic cavity at day 20; placental layers in the uterine wall at day 22 to 24; zonary placenta at day 27 to 30; embryo and heartbeat at day 23 to 25; yolk sac membrane at day 25 to 28; allantoic membrane at day 27 to 31; choroid plexus of the brain at day 31 to 35; fetal movement at day 34 to 36; skeleton at day 33 to 39; bladder and stomach at day 35 to 39; kidney at day 39 to 47; and liver hypoechoic, compared with lung, at day 38 to 42. Extra-fetal structures were measurable from day 20 or 22 through day 48. Chorionic cavity diameter increased from 0.2 +/- 0.0 cm to 3.3 +/- 0.2 cm, outer uterine diameter increased from 0.8 +/- 0.03 cm to 4.8 +/- 0.2 cm, length of chorionic cavity or zonary placenta increased from 0.3 +/- 0.03 cm to 4.9 +/- 0.05 cm, uterine wall thickness increased from 0.3 +/- 0.03 cm to 0.8 +/- 0.01 cm, and placental thickness increased from 0.1 +/- 0.0 cm to 0.5 +/- 0.05 cm. Chorionic cavity diameter, outer uterine diameter, and placental length each increased at a linear rate through day 37, after which time, each had a marked plateau in growth. Of the extra-fetal structures, chorionic cavity diameter was the most accurate for estimation of gestational age. All of the fetal structures studied increased at an increasing (second order) rate. Crown-rump length increased from 0.3 +/- 0.05 cm on day 24 to 9.2 +/- 0.2 cm on day 48. Body diameter increased from 0.2 +/- 0.03 cm on day 24 to 4.6 +/- 0.15 cm on day 60. Head diameter increased from 0.8 +/- 0.05 cm on day 34 to 2.7 +/- 0.04 cm on day 60. Of the fetal structures, head diameter was the most accurate for estimation of gestational age. 相似文献
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Inherited disorders of sexual development (DSD) cause sterility and infertility in horses. Mutations causing such disorders have been identified in other mammals, but there is little information on the molecular causes in horses. While the equine genome sequence has made it possible to identify candidate genes, additional tools are needed to routinely screen them for causative mutations. In this study, we designed a screening panel of polymerase chain reaction primer pairs for 15 equine genes. These are the candidate genes for testicular or ovotesticular XX DSD and XY DSD, the latter of which includes gonadal dysgenesis, androgen insensitivity syndrome (AIS), persistent Mullerian duct syndrome and isolated cryptorchidism. Six horses with testicular or ovotesticular XX DSD and controls were screened. In addition, candidate genes for androgen insensitivity syndrome, persistent Mullerian duct syndrome and isolated cryptorchidism were screened in normal horses. While no sequence variants were uniquely associated with XX DSD, the 38 sequence variants identified can serve as intragenic markers in genome-wide association studies or linkage studies to hasten mutation identification in equine XX DSD and XY DSD. 相似文献
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Kothapalli KS Kirkness EF Vanwormer R Meyers-Wallen VN 《Veterinary journal (London, England : 1997)》2006,171(3):559-561
DMRT1, which encodes a zinc finger-like DNA binding motif, is a well-conserved gene that is involved in testis differentiation in a variety of mammalian and non-mammalian vertebrates. The objective of this study was to determine whether a DMRT1 microsatellite marker allele is associated with the affected phenotype in a pedigree of canine SRY-negative XX sex reversal generated from an American Cocker spaniel founder. Ten affected dogs and their parents and grandparents were genotyped. Four alleles at this locus and five different genotypes were found in this pedigree. All affected dogs inherited this trait from the foundation sire of this colony. Thus, the disease-causing mutation should be identical by descent in all affected dogs. Six affected dogs were found to have genotypes at this locus that were different from those of the founder sire. These results indicate that DMRT1 is an unlikely candidate gene for SRY-negative XX sex reversal in this model. 相似文献