32 results on '"Christensen BW"'
Search Results
2. Population-based anti-Müllerian hormone reference intervals help define gonadal status in the bitch.
- Author
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Conley AJ, Berger T, Caruso CJ, Cotterman RF, Jones T, Christensen BW, Hollinshead FK, and Place NJ
- Subjects
- Animals, Dogs, Female, Reference Values, Retrospective Studies, Inhibins blood, Hysterectomy veterinary, Enzyme-Linked Immunosorbent Assay veterinary, Anti-Mullerian Hormone blood, Ovariectomy veterinary
- Abstract
Objective: To establish statistically valid, population-based reference intervals (RIs) for canine anti-Müllerian hormone (AMH) and define changes in AMH and inhibin-B in bitches during breeding cycles., Methods: A homologous canine ELISA was used to measure AMH in serum samples (collected between May 2019 and July 2024) from 102 intact and 78 reportedly ovariohysterectomized (OVH) bitches and 8 bitches before and after ovariohysterectomy, and in longitudinal samples from 24 bitches undergoing breeding management. Established 95% RIs were used in a retrospective assessment of 3,193 clinical submissions. Cyclic variation of AMH and inhibin-B (heterologous ELISA) were regressed with time and normalized to the rise in progesterone in samples from breeding bitches., Results: Intact and OVH RIs for AMH were calculated with and without inclusion of 7 samples from reportedly OVH bitches that had AMH concentrations in the intact RI. Anti-Müllerian hormone and inhibin-B were positively correlated, and AMH was 3 times higher in proestrus than in estrus. Retrospectively, of 3,193 samples submitted for clinical AMH testing, 41% to 56% were in or above the intact AMH interval, 37% to 44% were within the OVH interval, and < 10% were inconclusive, depending on how RIs were defined., Conclusions: Statistically valid, population-based RIs establish a sound basis for interpreting results of clinical submissions requesting AMH to assess gonadal status in the bitch., Clinical Relevance: Confirmation of cyclic variation in AMH (and, for the first time, inhibin-B) reaffirms proestrus as the optimum time to draw samples, and ≤ 10% of samples submitted for determination of gonadal status are expected to fall in an inconclusive AMH RI.
- Published
- 2024
- Full Text
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3. An investigation of the discrepancy between set and actual temperature of neonatal incubators: concern for hypothermia and hyperthermia.
- Author
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Christensen BW and Erb HN
- Subjects
- Animals, Dogs, Temperature, Body Temperature physiology, Incubators, Hypothermia veterinary, Hyperthermia, Induced veterinary
- Abstract
Objective: To document any discordance between the set temperature and independently measured temperature of neonatal incubators in order to determine the potential of neonatal incubators to cause hypothermia or hyperthermia in neonatal animals., Sample: 5 different veterinary neonatal incubators from 2 separate manufacturers., Methods: Internal temperatures of 5 incubators from 2 manufacturers were monitored with both internal and external monitoring devices to determine how much incubator temperatures might vary from what is reported on the incubator thermostat. The study was conducted on May 25, 2022., Results: Increases in temperature as measured by thermocouple and infrared sensors of > 2 °C were detected in 3 of the 5 (60%; 95% CI, 17% to 93%) tested incubators. Temperatures exceeded 41 °C at times, despite the incubator thermostat being set to 35 °C., Clinical Relevance: Neonatal puppies have a decreased capacity to thermoregulate and are susceptible to both hypothermia and hyperthermia if environmental temperatures are not kept within a proper range. Core temperatures below 35.0 °C lead to bradycardia, dyspnea, loss of suckle reflex, hypoglycemia, gastrointestinal ileus, and multiple organ failure; temperatures above 41.1 °C lead to pulmonary edema, petechial and ecchymotic hemorrhage in multiple organs, and death.
- Published
- 2023
- Full Text
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4. Canine Semen Evaluation and Processing.
- Author
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Christensen BW and Meyers S
- Subjects
- Male, Dogs, Animals, Spermatozoa, Cryopreservation veterinary, Sperm Motility, Semen, Semen Preservation veterinary
- Abstract
Advances in canine semen evaluation have progressed over time in fits and spurts, interspersed with long periods of relative inactivity. Despite exciting advances in the semen analysis, clinical canine theriogenology has been in a period of relative inactivity for a number of decades since initial advances in canine semen freezing in the mid 20th century. This review describes ways that the clinical practice of canine semen evaluation should improve, given the state of current knowledge., (Copyright © 2023 Elsevier Inc. All rights reserved.)
- Published
- 2023
- Full Text
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5. Progesterone Analysis in Canine Breeding Management.
- Author
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Conley AJ, Gonzales KL, Erb HN, and Christensen BW
- Subjects
- Pregnancy, Female, Animals, Dogs, Cesarean Section veterinary, Progesterone, Reproduction
- Abstract
Progesterone is a worthwhile addition to the clinical assessment of cycle stage for breeding, elective cesarian delivery, and reproductive management in the bitch if reliably measured. Clinical decisions based on systemic progesterone concentrations also require the rapid return of results. Most commercially accessible analyses capable of returning results within a day still rely primarily on immunoassays of one kind or another. Point-of-care instruments utilizing similar technology have been developed more recently to enable results to be generated in-house. Repeated monitoring of progesterone on whatever platform can be useful if consistent collection and analysis protocols ensure acceptable precision, accuracy, and repeatability., (Copyright © 2023 Elsevier Inc. All rights reserved.)
- Published
- 2023
- Full Text
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6. Cardiotoxicity of BTK inhibitors: ibrutinib and beyond.
- Author
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Christensen BW, Zaha VG, and Awan FT
- Subjects
- Adenine analogs & derivatives, Agammaglobulinaemia Tyrosine Kinase, Cardiotoxicity drug therapy, Cardiotoxicity etiology, Humans, Piperidines, Protein Kinase Inhibitors adverse effects, Pyrimidines adverse effects, Hypertension, Leukemia, Lymphocytic, Chronic, B-Cell drug therapy, Leukemia, Lymphocytic, Chronic, B-Cell pathology
- Abstract
Introduction: The development of Bruton
s Tyrosine Kinase (BTK) inhibitors has transformed the treatment of B-cell malignancies and other non-malignant conditions. Management of the unique cardiotoxic profile of these agents requires prompt recognition and a multi-disciplinary approach., Areas Covered: The increasing indications and addition of newer agents to clinical practice and emergence of BTK inhibitor-related cardiac adverse events have complicated the management decisions for utilization of this class of therapy. We review the incidence, mechanisms, and management approaches for BTK inhibitor-related atrial fibrillation, hypertension, and ventricular arrhythmias., Expert Opinion: The newer BTK inhibitor acalabrutinib represents a new standard of care in front-line chronic lymphocytic leukemia (CLL) given the results of the ELEVATE-RR trial demonstrating comparable efficacy and a more favorable toxicity profile especially with regard to cardiac adverse events as compared to ibrutinib. Often not recognized by clinicians, BTK inhibitor-induced hypertension is common and can be severe, requiring prompt recognition and initiation or adjustment of anti-hypertensive medications to prevent major adverse cardiac outcomes. Novel BTK inhibitors in development are being designed to overcome the patterns of resistance from first-generation agents and to minimize off-target kinase activity, with promising toxicity profiles in early trials. - Published
- 2022
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7. Blurred Vision and Gastrointestinal Bleeding in a Patient With HIV.
- Author
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Christensen BW, Li HC, and Huerta S
- Subjects
- Cytomegalovirus Retinitis complications, Enteritis complications, Gastrointestinal Hemorrhage etiology, HIV Infections diagnosis, HIV Infections drug therapy, Humans, Lymphoma, Large B-Cell, Diffuse diagnostic imaging, Lymphoma, Large B-Cell, Diffuse drug therapy, Lymphoma, Large B-Cell, Diffuse pathology, Male, Middle Aged, Cytomegalovirus Retinitis diagnosis, Enteritis diagnosis, Gastrointestinal Hemorrhage diagnosis, HIV Infections complications, Lymphoma, Large B-Cell, Diffuse diagnosis, Vision Disorders virology
- Published
- 2022
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8. Randomized Comparative Trial of Acupuncture and Exercise Versus Uterine Ecbolics in the Treatment of Persistent Postbreeding Endometritis in Mares.
- Author
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Swift LA, Christensen BW, Samocha MB, le Jeune SS, Millares-Ramirez EM, and Dujovne GA
- Subjects
- Animals, Female, Horses, Acupuncture Therapy veterinary, Endometritis therapy, Endometritis veterinary, Horse Diseases therapy, Physical Conditioning, Animal
- Abstract
Although exercise and acupuncture are frequently used therapies to treat persistent postbreeding endometritis, their efficacy to date is unproven. The objective of this study was to determine if exercise and acupuncture are effective methods to reduce intrauterine fluid and compare the effectiveness of these treatments to the use of uterine ecbolics. Twelve mares susceptible to postbreeding endometritis were enrolled in the study with a randomized cross-over design using both positive and negative controls. During each estrous cycle, mares were randomized into one of six treatment groups, including stall rest (SR), oxytocin, cloprostenol, exercise, electroacupuncture, and oxytocin and exercise. Each mare was challenged with an insemination dose of 500 × 10
6 dead sperm at time 0 hours. Intrauterine fluid measurements were taken at 0, 4, 24, 48, 72, and 96 hours postbreeding. Associations between treatment efficacy and fluid clearance were investigated using a random-effects logistic regression model that controlled for positive uterine culture. Compared with the SR negative control, exercise was the most effective treatment and had 29.7 times increased odds of fluid clearance. The second most effective treatment was oxytocin alone, with 16.9 times increased odds of fluid clearance. This was followed by cloprostenol that had 10.6 greater odds of fluid clearance, and finally, the treatment that combined exercise with oxytocin had 8.4 times greater odds of fluid clearance. Results from this study confirm that exercise and exercise combined with oxytocin are effective methods to clear intrauterine fluid., (Copyright © 2019. Published by Elsevier Inc.)- Published
- 2020
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9. A retrospective cost analysis of the frequency and cost of transfusion premedications.
- Author
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Christensen BW, Rubinstein SM, Bastakoty D, Savani BN, and Booth GS
- Abstract
Background: Acetaminophen and diphenhydramine are routinely administered to prevent febrile non-hemolytic and allergic blood transfusion reactions despite multiple randomized controlled trials demonstrating that this practice lacks efficacy. As a result, patients are exposed to the adverse effects of these medications and their financial burdens with no expected benefit. The aim of this study was to quantify the frequency and cost of transfusion premedications in patients with acute myeloid leukemia (AML)., Study Design and Methods: This was a retrospective study of patients with AML admitted to Vanderbilt University Medical Center (VUMC) for induction chemotherapy between January 2008 and December 2016. Data were collected on the number of platelet and packed red blood cell (PRBC) transfusions each patient received during the initial inpatient encounter for AML, as well as on the administration of premedications prior to each transfusion., Results: During the 9-year study period, 948 AML patients received a total of 19,820 transfusions. Of these, 30% were preceded by oral diphenhydramine, 8% by intravenous diphenhydramine, and 39% by oral acetaminophen. The percentage of patients that received a transfusion preceded by a premedication increased over the study period (p = 0.03), as did the percentage of transfusions preceded by a premedication (p = 0.02). The total unadjusted cost of pre-transfusion medications to the institution during the study period was $50,309.77, or $52.67 per patient with AML. The cost of premedications per patient did not increase over the study period (p = .45)., Conclusions: Routine transfusion premedication administration is common in AML patients and not well-supported by available evidence., (© 2019 AABB.)
- Published
- 2019
- Full Text
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10. Addition of price transparency to an education and feedback intervention reduces utilization of inpatient echocardiography by resident physicians.
- Author
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Kozak PM, Trumbo SP, Christensen BW, Leverenz DL, Shotwell MS, and Kingeter AJ
- Subjects
- Attitude of Health Personnel, Cost Savings, Cost-Benefit Analysis, Echocardiography economics, Education, Medical, Continuing economics, Feasibility Studies, Health Care Costs, Health Knowledge, Attitudes, Practice, Humans, Internship and Residency economics, Practice Patterns, Physicians' economics, Predictive Value of Tests, Prospective Studies, Quality Improvement economics, Quality Improvement trends, Quality Indicators, Health Care economics, Quality Indicators, Health Care trends, Unnecessary Procedures economics, Echocardiography trends, Education, Medical, Continuing trends, Formative Feedback, Hospital Costs trends, Inpatients, Internship and Residency trends, Practice Patterns, Physicians' trends, Unnecessary Procedures trends
- Abstract
Previous studies have demonstrated the impact of appropriate use criteria (AUC) education and feedback interventions in reducing unnecessary ordering of transthoracic echocardiography (TTE) by trainees. To our knowledge, no study has evaluated the impact of the addition of price transparency to this education and feedback model on TTE utilization by resident physicians. We performed an education and feedback quality improvement initiative combining charge transparency data with information on AUC. We hypothesized that the initiative would reduce the number of complete TTE ordered and increase the number of limited TTE ordered, anticipating there would be substitution of limited for complete studies. Residents rotating on inpatient teaching cardiology ward teams received education on AUC for TTE, indications for limited TTE, and hospital charges for TTE. Feedback was provided on the quantity and charges for complete and limited TTE ordered by each team. We analyzed the effects of the intervention using a linear mixed effects regression model to adjust for potential confounders. The post-intervention weeks showed a reduction of 4.6 complete TTE orders per 100 patients from previous weekly baseline of 31.3 complete TTE orders per 100 patients (p value = 0.012). Charges for complete TTE decreased $122 from baseline of $980 per patient (p value = 0.040) on a per-week basis. Secondarily, there was no statistically significant change in limited TTE ordering during the intervention period. This initiative shows the feasibility of a house staff-driven charge transparency and education/feedback initiative that decreased medical residents' ordering of inpatient TTE.
- Published
- 2019
- Full Text
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11. Canine Prostate Disease.
- Author
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Christensen BW
- Subjects
- Animals, Dog Diseases prevention & control, Dogs, Male, Prostatic Hyperplasia diagnosis, Prostatic Hyperplasia prevention & control, Dog Diseases diagnosis, Orchiectomy veterinary, Prostatic Hyperplasia veterinary
- Abstract
All intact, male dogs will experience benign prostatic hyperplasia and hypertrophy, usually by around 6 years old. Although these dogs will be predisposed to prostatic infections, only a small subset will actually develop infections or show clinical signs of discomfort or subfertility. Neutered male dogs have a higher incidence of neoplasia associated with the prostate. Updated diagnostic tests, including canine prostate-specific arginine esterase, are discussed. Castration is compared with medical treatment options. Updated treatment recommendations include reducing antibiotic exposure to 4 weeks for bacterial infections and use of nonsteroidal antiinflammatory drugs for neoplastic disease., (Copyright © 2018 Elsevier Inc. All rights reserved.)
- Published
- 2018
- Full Text
- View/download PDF
12. Helping Miracles Happen.
- Author
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Christensen BW
- Subjects
- Animals, Reproduction, Veterinary Medicine trends
- Published
- 2018
- Full Text
- View/download PDF
13. Theriogenology Question of the Month.
- Author
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Boye JK, Byrne BA, Alex CE, Affolter VK, Christensen BW, and Dujovne GA
- Subjects
- Aborted Fetus microbiology, Aborted Fetus pathology, Animals, Aspergillosis pathology, Aspergillus isolation & purification, Female, Horse Diseases pathology, Horses, Placenta Diseases microbiology, Pregnancy, Abortion, Veterinary pathology, Aspergillosis veterinary, Horse Diseases microbiology, Placenta Diseases veterinary
- Published
- 2017
- Full Text
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14. Studies of wolf x coyote hybridization via artificial insemination.
- Author
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Mech LD, Asa CS, Callahan M, Christensen BW, Smith F, and Young JK
- Subjects
- Animals, Crosses, Genetic, Female, Genetics, Population, Geography, Male, North America, Phylogeny, Sperm Motility, Coyotes genetics, Hybridization, Genetic, Insemination, Artificial, Wolves genetics
- Abstract
Following the production of western gray wolf (Canis lupus) x western coyote (Canis latrans) hybrids via artificial insemination (AI), the present article documents that the hybrids survived in captivity for at least 4 years and successfully bred with each other. It further reports that backcrossing one of the hybrids to a male gray wolf by AI also resulted in the birth of live pups that have survived for at least 10 months. All male hybrids (F1 and F2) produced sperm by about 10 months of age, and sperm quality of the F1 males fell within the fertile range for domestic dogs, but sperm motility and morphology, in particular, were low in F2 males at 10 months but improved in samples taken at 22 months of age. These studies are relevant to a long-standing controversy about the identity of the red wolf (Canis rufus), the existence of a proposed new species (Canis lycaon) of gray wolf, and to the role of hybridization in mammalian evolution.
- Published
- 2017
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15. A comparison of fecal steroid metabolite concentrations between harem and bachelor stallions in a free-Ranging population of przewalski's horses (Equus ferus przewalskii).
- Author
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D'Souza-Anjo M, Christensen BW, Brabender K, Zimmermann W, Kass PH, and Schwarzenberger F
- Subjects
- Animals, Animals, Zoo, Male, Androsterone analysis, Estrogens analysis, Feces chemistry, Horses physiology
- Abstract
The aim of this study was to determine whether concentrations of reproductive steroid hormone metabolites significantly differed between harem stallions and bachelor stallions in the free ranging group of Przewalski's horses (Equus ferus przewalskii) at the Hortobágy National Park in Hungary. Throughout the study, fecal samples were collected from 21 harem stallions and 15 bachelor stallions and analyzed for immunoreactive estrogen and androgen metabolites. Harem stallions demonstrated significantly higher concentrations of estrogen (P < 0.001) and epi-androsterone (P < 0.001), but not testosterone (P = 0.426). These findings confirm that sociosexual status has a significant effect on androgen concentrations in individual Przewalski stallions. Zoo Biol. 36:127-131, 2017. © 2017 Wiley Periodicals, Inc., (© 2017 Wiley Periodicals, Inc.)
- Published
- 2017
- Full Text
- View/download PDF
16. Utility of an Equine Clinical Skills Course: A Pilot Study.
- Author
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Christensen BW and Danielson JA
- Subjects
- Animals, Horses, Pilot Projects, Clinical Competence, Education, Veterinary, Students psychology
- Abstract
Recent publications have revealed inadequacies in the veterinary training of future equine practitioners. To help address this problem, a 2-week Equine Clinical Skills course was designed and implemented to provide fourth-year veterinary students with opportunities to have hands-on experience with common equine clinical skills using live animals and cadavers. Alumni and employers of alumni were surveyed to determine whether or not students participating in the course were more competent performing clinical skills during their first year post-graduation than those who had not participated in the course. Students who participated in the course were also surveyed before and after completing the course to determine whether or not their self-assessed skills improved during the course. Alumni who had taken the course rated their ability to perform the clinical skills more highly than alumni who had not taken the course. Similarly, students participating in the course indicated that they were significantly more able to perform the clinical skills after the course than when it began. Employers did not indicate a difference between the clinical skills of those who had taken the course and those who had not. Because this study involved a limited number of respondents from one institution, further studies should be conducted to replicate these findings and determine their generalizability.
- Published
- 2016
- Full Text
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17. Theriogenology Question of the Month. Neoplasms of the penis and testis.
- Author
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Scott CJ, Christensen BW, Dechant JE, Espinosa P, and LaDouceur EE
- Subjects
- Amputation, Surgical veterinary, Animals, Carcinoma, Squamous Cell diagnosis, Carcinoma, Squamous Cell pathology, Carcinoma, Squamous Cell surgery, Horse Diseases pathology, Horse Diseases surgery, Horses, Male, Orchiectomy veterinary, Penile Neoplasms diagnosis, Penile Neoplasms pathology, Penile Neoplasms surgery, Penis surgery, Seminoma diagnosis, Seminoma pathology, Seminoma surgery, Treatment Outcome, Carcinoma, Squamous Cell veterinary, Horse Diseases diagnosis, Penile Neoplasms veterinary, Seminoma veterinary
- Published
- 2015
- Full Text
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18. Theriogenology question of the month. Granulosa-theca cell tumor.
- Author
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Myers JE, Dujovne GA, Galuppo LD, Conley AJ, Moore PF, Mok MY, Aristizabal FA, and Christensen BW
- Subjects
- Animals, Female, Granulosa Cell Tumor diagnosis, Granulosa Cell Tumor diagnostic imaging, Granulosa Cell Tumor surgery, Horse Diseases diagnostic imaging, Horse Diseases surgery, Horses, Radiography, Granulosa Cell Tumor veterinary, Horse Diseases diagnosis
- Published
- 2014
- Full Text
- View/download PDF
19. Production of hybrids between western gray wolves and western coyotes.
- Author
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Mech LD, Christensen BW, Asa CS, Callahan M, and Young JK
- Subjects
- Animals, DNA, Mitochondrial genetics, Female, Genetics, Population methods, Male, Coyotes genetics, Hybridization, Genetic genetics, Wolves genetics
- Abstract
Using artificial insemination we attempted to produce hybrids between captive, male, western, gray wolves (Canis lupus) and female, western coyotes (Canis latrans) to determine whether their gametes would be compatible and the coyotes could produce and nurture offspring. The results contribute new information to an ongoing controversy over whether the eastern wolf (Canis lycaon) is a valid unique species that could be subject to the U. S. Endangered Species Act. Attempts with transcervically deposited wolf semen into nine coyotes over two breeding seasons yielded three coyote pregnancies. One coyote ate her pups, another produced a resorbed fetus and a dead fetus by C-section, and the third produced seven hybrids, six of which survived. These results show that, although it might be unlikely for male western wolves to successfully produce offspring with female western coyotes under natural conditions, western-gray-wolf sperm are compatible with western-coyote ova and that at least one coyote could produce and nurture hybrid offspring. This finding in turn demonstrates that gamete incompatibility would not have prevented western, gray wolves from inseminating western coyotes and thus producing hybrids with coyote mtDNA, a claim that counters the view that the eastern wolf is a separate species. However, some of the difficulties experienced by the other inseminated coyotes tend to temper that finding and suggest that more experimentation is needed, including determining the behavioral and physical compatibility of western gray wolves copulating with western coyotes. Thus although our study adds new information to the controversy, it does not settle it. Further study is needed to determine whether the putative Canis lycaon is indeed a unique species.
- Published
- 2014
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20. Kinematic activity of gray wolf (Canis lupus) sperm in different extenders, added before or after centrifugation.
- Author
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Christensen BW, Asa CS, Wang C, Bauman K, Agnew MK, Lorton SP, and Callahan M
- Subjects
- Animals, Biomechanical Phenomena, Cell Survival, Centrifugation veterinary, Male, Semen Preservation methods, Specimen Handling methods, Specimen Handling veterinary, Spermatozoa metabolism, Semen Preservation veterinary, Spermatozoa physiology, Wolves physiology
- Abstract
We evaluated two approaches to improving in vitro wolf sperm survival. Both approaches aimed to reduce the exposure of sperm to prostatic fluid resulting from electroejaculation: (1) use of extender formulations recently developed for the domestic dog (the most closely related domestic species); and (2) dilution of ejaculate shortly after semen collection. Three commercial extenders were compared with the TRIS-based extender we had previously used. We also compared the effects on motility of adding extender immediately after collection to our previous protocol in which extender was added after centrifugation. Both subjective and objective (computer-assisted semen analysis program) kinematic measurements were made. Relatively minor differences were noted (and not in total or progressive motility) between the centrifugation protocols. Two of the commercial extenders resulted in significant improvement in motility over the TRIS-based extender and one of the other commercial extenders at 8 hours after collection (mean ± SEM; total motility was 68.3 ± 4.0% and 70.0 ± 4.0% compared with 53.3 ± 4.0% and 55.0 ± 4.0%, respectively; progressive motility 58.6 ± 5.4% and 57.1 ± 5.4% compared with 32.8 ± 5.4% and 39.3 ± 5.4%; P < 0.05). We inferred that components in two of the commercial dog extenders might provide more protection for wolf sperm, prolonging their motility., (Copyright © 2013 Elsevier Inc. All rights reserved.)
- Published
- 2013
- Full Text
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21. Disorders of sexual development in dogs and cats.
- Author
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Christensen BW
- Subjects
- Animals, Cat Diseases genetics, Cat Diseases therapy, Cats, Disorders of Sex Development diagnosis, Disorders of Sex Development genetics, Disorders of Sex Development therapy, Dog Diseases genetics, Dog Diseases therapy, Dogs, Female, Gonadal Dysgenesis diagnosis, Male, Sex Chromosome Disorders diagnosis, Sexual Development genetics, Cat Diseases diagnosis, Disorders of Sex Development veterinary, Dog Diseases diagnosis, Gonadal Dysgenesis veterinary, Sex Chromosome Disorders veterinary, Sexual Development physiology
- Abstract
Determination of a mammal’s sex begins at conception with the establishment of genotype and continues from there as the expression of specific genes directs the bipotential gonad to develop. The gonad further directs the sexual differentiation of the individual. Deviations from either of these pathways at any stage results in disorders of sexual development. Definitive diagnosis minimally requires a karyotype, histopathologic evaluation of the gonads, and gross description of the genital anatomy, with more complete diagnostic answers achieved through other diagnostic tests. This article covers normal and abnormal development of the reproductive organs with emphasis on diagnosis and treatment.
- Published
- 2012
- Full Text
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22. Effect of semen collection method on sperm motility of gray wolves (Canis lupus) and domestic dogs (C. l. familiaris).
- Author
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Christensen BW, Asa CS, Wang C, Vansandt L, Bauman K, Callahan M, Jens JK, and Ellinwood NM
- Subjects
- Animals, Ejaculation, Electric Stimulation, Male, Specimen Handling methods, Dogs, Semen, Specimen Handling veterinary, Sperm Motility, Wolves
- Abstract
Genetic management of Mexican gray wolves includes semen banking, but due to the small number of animals in the population and handling restrictions, improvements in semen collection and cryopreservation rely on results from studies of domestic dogs. Semen collection from wolves requires anesthesia and electroejaculation, which introduce potentially important variables into species comparisons, as dog semen is typically collected manually from conscious animals. To investigate possible effects of collection method on semen quality, we compared semen collection by the traditional manual method and by electroejaculation (EE) in a group of dogs (n = 5) to collection by EE only in wolves (n = 7). Samples were divided into two aliquots: neat or diluted in Tris/egg yolk extender, with motility evaluated at intervals up to 24 h. There were no differences (P > 0.10) in sperm motility in either neat or extended samples at 24 h from EE dogs and wolves, although motility of the wolf neat samples declined more rapidly (P < 0.05). However, there were differences (P < 0.01) between EE and manually collected dog semen in motility at 24 h, in both the neat and extended samples. Therefore, general motility patterns of dog and wolf semen collected by EE were similar, especially when diluted with a Tris/egg yolk extender, but sperm collected from dogs by EE did not maintain motility as long as manually collected samples, perhaps related to the longer exposure of EE samples to more prostate fluid., (Copyright © 2011 Elsevier Inc. All rights reserved.)
- Published
- 2011
- Full Text
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23. Effects of sociosexual environment on serum testosterone in captive male African rhinoceros.
- Author
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Christensen BW, Troedsson MH, Young LJ, Oliva M, and Penfold LM
- Subjects
- Animals, Animals, Zoo, Enzyme-Linked Immunosorbent Assay veterinary, Female, Male, Perissodactyla blood, Perissodactyla physiology, Sexual Behavior, Animal physiology, Social Behavior, Testosterone blood
- Abstract
The relationships between testosterone concentrations in male African rhinoceros and the presence of conspecific males and females were investigated. Serum testosterone concentrations were measured using enzyme-linked immunoassay (EIA) in 37 male black rhinoceros (Diceros bicornis) and 21 male white rhinoceros (Ceratotherium simum) housed at 37 institutions in the USA. Testosterone concentrations in both black (n=37) and white (n=21) rhinoceros males rose with increasing numbers of females present (P<0.05). Average testosterone concentrations also rose with an increased number of conspecific males (n=34) in black rhinoceros (P<0.05). However, no specific pattern was found among male white rhinoceros housed with other males. We inferred that introduction of females to a male may play an important role in stimulating libido and spermatogenesis. The similar response of black rhinoceros and white rhinoceros to increased numbers of females suggested that, at least historically, herd structure for blacks may have been more similar to whites than previously realized, and should be investigated further.
- Published
- 2009
- Full Text
- View/download PDF
24. Theriogenology question of the month. Bleeding varicose veins.
- Author
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Christensen BW, Troedsson MH, Roberts JF, Pozor MA, Macpherson ML, and Eichelberger AC
- Subjects
- Actinomycetales Infections diagnosis, Actinomycetales Infections diagnostic imaging, Animals, Diagnosis, Differential, Extraembryonic Membranes diagnostic imaging, Female, Horse Diseases diagnosis, Horses, Placenta Diseases diagnosis, Placenta Diseases diagnostic imaging, Pregnancy, Pregnancy Complications, Infectious diagnosis, Pregnancy Complications, Infectious diagnostic imaging, Pregnancy Outcome, Ultrasonography, Varicose Veins diagnosis, Varicose Veins diagnostic imaging, Actinomycetales Infections veterinary, Horse Diseases diagnostic imaging, Placenta Diseases veterinary, Pregnancy Complications, Infectious veterinary, Varicose Veins veterinary
- Published
- 2006
- Full Text
- View/download PDF
25. Nocardioform placentitis with isolation of Amycolatopsis spp in a Florida-bred mare.
- Author
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Christensen BW, Roberts JF, Pozor MA, Giguere S, Sells SF, and Donahue JM
- Subjects
- Actinomycetales isolation & purification, Actinomycetales Infections diagnosis, Actinomycetales Infections microbiology, Actinomycetales Infections pathology, Animals, Female, Horse Diseases diagnosis, Horse Diseases pathology, Horses, Placenta microbiology, Placenta pathology, Placenta Diseases diagnosis, Placenta Diseases microbiology, Placenta Diseases pathology, Pregnancy, Pregnancy Complications, Infectious diagnosis, Pregnancy Complications, Infectious microbiology, Pregnancy Complications, Infectious pathology, Pregnancy Outcome, Actinomycetales Infections veterinary, Horse Diseases microbiology, Placenta Diseases veterinary, Pregnancy Complications, Infectious veterinary
- Abstract
Case Description: A 4-year-old Thoroughbred mare was evaluated because of placental abnormalities and a retained placental remnant., Clinical Findings: Microbial culture of the placenta yielded pure growth of Amycolatopsis spp. Histologic examination of the placenta revealed a focally expanding chorionitis with intralesional gram-positive filamentous bacilli and multifocal allantoic adenomatous hyperplasia on the apposing allantoic surface., Treatment and Outcome: Treatment with lavage and oxytocin resulted in expulsion of the placental remnant within hours of parturition. The mare did not become pregnant again despite multiple breedings. The foal appeared healthy but died of complications during an elective surgical procedure at 7 weeks of age., Conclusions and Clinical Relevance: To the author's knowledge, all previously confirmed cases of nocardioform placentitis have been in mares bred in the central Kentucky region. Indications that the pathogen in the mare reported here is a different species than that isolated in Kentucky suggest that this is an emerging disease. Mares with nocardioform placentitis usually do not have the same clinical signs as mares with placentitis resulting from an ascending pathogen.
- Published
- 2006
- Full Text
- View/download PDF
26. Management of hydrops amnion in a mare resulting in birth of a live foal.
- Author
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Christensen BW, Troedsson MH, Murchie TA, Pozor MA, Macpherson ML, Estrada AH, Carrillo NA, Mackay RJ, Roberts GD, and Langlois J
- Subjects
- Animals, Female, Horses, Hydrops Fetalis, Limb Deformities, Congenital surgery, Pregnancy, Pregnancy Complications diagnostic imaging, Pregnancy Outcome veterinary, Ultrasonography, Prenatal veterinary, Fetus abnormalities, Horse Diseases diagnostic imaging, Limb Deformities, Congenital veterinary, Pregnancy Complications veterinary
- Abstract
Case Description: A 19-year-old Thoroughbred mare was evaluated at 265 days of gestation with a markedly distended abdomen and edema of the ventral portion of the abdomen., Clinical Findings: The uterus was distended over the pelvic rim, making transrectal palpation of the fetus impossible. Transabdominal ultrasonography revealed excessive amounts of fetal fluid. Results of analysis of fluid obtained via amnio- and allantocentesis confirmed that the amniotic cavity was large., Treatment and Outcome: The mare was monitored for signs of weakness of the prepubic tendon and abdominal wall. The fetus and placenta were monitored for signs of stress and pending abortion. Flunixin meglumine and altrenogest were administered to the mare. Parturition was attended and occurred at 321 days' gestation. Postpartum complications in the mare included hypovolemic shock and cardiac arrhythmias. Both conditions were treated, and the mare recovered. The foal was considered small, had bilateral angular limb deformities, and was unable to nurse. The foal was given plasma for failure of passive transfer of immunity. Ten months later, the foal underwent procedures to correct limb deformities., Conclusions and Clinical Relevance: Hydrops conditions are rare in horses, with hydrops allantois occurring more frequently than hydrops amnion; reportedly result in fetal or neonatal death; and may result in death of or injury to the mare. Close monitoring of maternal and fetal health in combination with supportive treatment of the mare can result in the safe progression of a hydrops pregnancy and the birth of a live foal.
- Published
- 2006
- Full Text
- View/download PDF
27. Effect of dietary protein on lean body wasting in dogs: correlation between loss of lean mass and markers of proteasome-dependent proteolysis.
- Author
-
Wakshlag JJ, Barr SC, Ordway GA, Kallfelz FA, Flaherty CE, Christensen BW, Shepard LA, Nydam DV, and Davenport GM
- Subjects
- Absorptiometry, Photon veterinary, Animals, Body Composition, Body Weight, Dietary Proteins metabolism, Energy Metabolism, Female, Gene Expression Regulation, Enzymologic, Muscle, Skeletal pathology, Proteasome Endopeptidase Complex, Adipose Tissue metabolism, Cysteine Endopeptidases metabolism, Dietary Proteins administration & dosage, Dogs metabolism, Multienzyme Complexes metabolism, Muscle, Skeletal metabolism
- Abstract
To determine the effect of dietary protein intake on lean body wasting in adult canines a study was undertaken to investigate the Ubiquitin Proteasome (UP) pathway and concurrent changes in lean and fat body mass of canines fed variable sources and concentrations of dietary protein. Purpose-bred, intact female canines (56) between the ages of 2 and 3 years were fed either 12 or 28% protein diet for 10 weeks. Each diet contained variable amounts of corn gluten meal and chicken protein sources in ratios of 100 : 0, 67 : 33, 33 : 67 and 0 : 100 per cent (w/w), respectively. All diets were isocaloric with calories coming from protein : fat : carbohydrate at the respective ratios of 12 : 40 : 48% for the 12% diets, and 28 : 40 : 32% for the 28% diets. Standard dual energy X-ray absorptiometry was performed to assess total body lean and fat mass at weeks 0 and 10 of the dietary trial. Muscle biopsies were also taken and processed for protein determination and standard gel electrophoresis with subsequent Western blotting for 20S proteasome and PA700 regulatory cap subunit p31. Statistical analysis revealed a moderate degree of correlation between increasing quantities of corn gluten, which is low in essential amino acids (i.e. lysine, tryptophan), and increasing loss of lean body mass over the 10-week study (R = 0.56). Furthermore, a moderate degree of correlation was observed between increasing concentrations of corn gluten protein and decreased expression of the p31 subunit of the 26S proteasome (R = 0.49). Additionally, the dogs consuming the 12% protein diets had a significant increase in fat mass regardless of the protein source. These findings suggest that lean body wasting in adult canines can be associated with the consumption of low protein diets consisting of predominantly corn gluten, which is likely due to imbalances or subclinical deficiencies of specific essential amino acids, and that low protein diets may augment accumulation of adipose tissue. Although the mechanisms remain unclear, alteration of molecular targets of skeletal muscle proteolysis, specifically involving the UP pathway occur.
- Published
- 2003
- Full Text
- View/download PDF
28. In defense of bats.
- Author
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Christensen BW
- Subjects
- Animals, Animals, Wild, Bites and Stings epidemiology, Bites and Stings veterinary, Prevalence, Rabies epidemiology, United States, Chiroptera, Disease Reservoirs veterinary, Rabies veterinary
- Published
- 2003
29. Community and individual considerations in legislation and test policy regarding HIV-infection in the Nordic countries--a cross national comparative study.
- Author
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Krasnik A, Bjoerner J, and Christensen BW
- Subjects
- Acquired Immunodeficiency Syndrome prevention & control, Confidentiality, Humans, Iceland, Mass Screening, Pregnant People, Registries, Scandinavian and Nordic Countries, Acquired Immunodeficiency Syndrome diagnosis, Health Policy, Internationality, Legislation, Medical, Voluntary Programs
- Abstract
The purpose of the study is to facilitate international co-operation and national development on AIDS-policy by describing and comparing the programmes on the control of AIDS in the five Nordic countries. This article is focusing especially on community and individual considerations in legislation and test policy regarding HIV-infection in relation to general testing, testing of special groups, registration, voluntariness and confidentiality. The data were collected in the period of April-December 1987 by a review of existing documental material, mailed questionnaires to key persons in the health agencies in each country and personal interviews with 60 representatives of relevant organisations and institutions. The analysis of the data demonstrate that all the Nordic countries are seeking compromises which try to satisfy individual as well as community needs, although with different weight attached to the elements involved. Compared with international recommendations, national AIDS-policies in the Nordic countries in some instances do not fully respect voluntariness and confidentiality. It is concluded that AIDS-policy should be studied in the context of national traditions concerning general health policy, individual rights and community protection.
- Published
- 1989
- Full Text
- View/download PDF
30. [WHO. 3. WHO's activities for a health strategy in the European countries].
- Author
-
Christensen BW
- Subjects
- Europe, Humans, Health Planning, Health Policy, World Health Organization
- Published
- 1984
31. [WHO. 2. Health strategy applies to all countries of the world].
- Author
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Christensen BW
- Subjects
- Global Health, Health Planning, Primary Health Care organization & administration, World Health Organization
- Published
- 1983
32. [WHO. 1. WHO resolution could have great significance for nurses].
- Author
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Christensen BW
- Subjects
- Denmark, Humans, Nurse Midwives, Nurses, Primary Health Care organization & administration, World Health Organization
- Published
- 1983
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