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1.
Reprod Domest Anim ; 47 Suppl 4: 38-45, 2012 Aug.
Article in English | MEDLINE | ID: mdl-22827348

ABSTRACT

Education in reproductive science is operating from an outdated paradigm of teaching and learning. Traditionally, reproductive education follows the pattern where students read a textbook, listen to instructor presentations, re-read the textbook and class notes and then complete a test. This paradigm is inefficient, costly and has not incorporated the potential that technology can offer with respect to increases in student learning. Further, teachers of reproductive science (and all of science for that matter) have little training in the use of documented methods of instructional design and cognitive psychology. Thus, most of us have learned to teach by repeating the approaches our mentors used (both good and bad). The technology now exists to explain complex topics using multimedia presentations in which digital animation and three-dimensional anatomical reconstructions greatly reduce time required for delivery while at the same time improving student understanding. With funding from the Small Business Innovation Research program through the U.S. Department of Education, we have developed and tested a multimedia approach to teaching complex concepts in reproductive physiology. The results of five separate experiments involving 1058 university students and 122 patients in an OB/GYN clinic indicate that students and patients learned as much or more in less time when viewing the multimedia presentations when compared to traditional teaching methodologies.


Subject(s)
Multimedia , Physiology/education , Reproduction/physiology , Adult , Anatomy/education , Female , Humans , Parturition/physiology , Students
2.
Anim Reprod Sci ; 105(1-2): 179-86, 2008 Apr.
Article in English | MEDLINE | ID: mdl-18280064

ABSTRACT

This paper outlines concerns pertaining to the future of professionals in the discipline of reproductive science. This discourse is based on the experiences, opinions and due considerations of the author. The major objective of this paper is to stimulate thinking, discussion and debate, as well as action aimed at correcting problems that may threaten the next generation of reproductive scientists. The most important points are that mentoring has been replaced with counting, and that academic positions with combined research and teaching components are less and less attractive due to the protracted PhD plus postdoctoral training periods, the extremely low funding rates for extramural grant proposals, and being rewarded on the basis of quantity rather than quality.


Subject(s)
Reproduction/physiology , Research/education , Research/trends , Animals , Humans
3.
Phys Rev Lett ; 96(7): 072301, 2006 Feb 24.
Article in English | MEDLINE | ID: mdl-16606077

ABSTRACT

Differential production cross sections of K+/- mesons have been measured in p + C and p + Au collisions at 1.6, 2.5, and 3.5 GeV proton beam energy. At beam energies close to the production threshold, the K- multiplicity is strongly enhanced with respect to proton-proton collisions. According to microscopic transport calculations, this enhancement is caused by two effects: the strangeness exchange reaction NY --> K- NN and an attractive in-medium K- N potential at saturation density.

4.
Phys Rev Lett ; 95(1): 012301, 2005 Jul 01.
Article in English | MEDLINE | ID: mdl-16090609

ABSTRACT

Azimuthal distributions of pi+, K+, and K- mesons have been measured in Au+Au reactions at 1.5A GeV and Ni+Ni reactions at 1.93 A GeV. In semicentral collisions at midrapidity, pi+ and K+ mesons are emitted preferentially perpendicular to the reaction plane in both collision systems. In contrast for K- mesons in Ni+Ni reactions, an in-plane elliptic flow was observed for the first time at these incident energies.

5.
Phys Rev Lett ; 91(15): 152301, 2003 Oct 10.
Article in English | MEDLINE | ID: mdl-14611460

ABSTRACT

Differential production cross sections of K- and K+ mesons have been measured in Ni+Ni and Au+Au collisions at a beam energy of 1.5 A GeV. The K(-)/K(+) ratio is found to be nearly constant as a function of the collision centrality and system size. The spectral slopes and the polar emission pattern differ for K- and K+ mesons. These observations indicate that K+ mesons decouple earlier from the fireball than K- mesons.

6.
Phys Rev Lett ; 90(23): 232501, 2003 Jun 13.
Article in English | MEDLINE | ID: mdl-12857251

ABSTRACT

An exclusive measurement of the Coulomb breakup of 8B into 7Be+p at 254A MeV allowed the study of the angular correlations of the breakup particles. These correlations demonstrate clearly that E1 multipolarity dominates and that E2 multipolarity can be neglected. By using a simple single-particle model for 8B and treating the breakup in first-order perturbation theory, we extract a zero-energy S factor of S17(0)=18.6+/-1.2+/-1.0 eV b, where the first error is experimental and the second one reflects the theoretical uncertainty in the extrapolation.

7.
J Anim Sci ; 80(1): 19-22, 2002 Jan.
Article in English | MEDLINE | ID: mdl-11831515

ABSTRACT

Thirty-six percent of American Wagyu bulls do not meet the current minimum standards set by the Society of Theriogenology for the breeding soundness exam. In contrast, only 15% of bulls of domestic breeds do not meet the minimum standards. Scrotal circumference measurements of Wagyu are smaller than those of other breeds. The objective of this research was to describe scrotal circumference of Wagyu bulls as it relates to age and BW. The data set consisted of 190 Wagyu bulls housed at two locations. One hundred forty-one bulls constituted the first set of data (location 1); scrotal circumference was measured one to six times per bull aged between 13 and 70 mo. Ninety-four of the bulls underwent semen evaluation for motility and morphology. Forty-nine bulls constituted the data set for which scrotal circumference and BW was measured one to nine times per bull between 5 and 21 mo of age (location 2). Mean scrotal circumference of bulls within each age group was as follows: 12 to 14 mo, 29.8 0.2 cm (mean +/- SE); 15 to 17 mo, 31.8 +/- 0.2 cm; 18 to 20 mo, 32.9 +/- 0.3 cm; 21 to 24 mo, 31.8 +/- 0.5 cm; and > 24 mo, 35.5 +/- 0.2 cm. Both age and BW were highly correlated to scrotal circumference (r = 0.81 and 0.82, respectively). Within each age group, there were a percentage of bulls that did not meet the minimum standard for scrotal circumference set by the Society of Theriogenology. The percentages were as follows: 12 to 14 mo, 46%; 15 to 17 mo, 25%; 18 to 20 mo, 33%; 21 to 24 mo, 42%; and > 24 mo, 32%. Morphology and motility were > 50% each in 91% of the bulls between ages 12 and 20 mo at location 1. Based on these data, it is recommended that Wagyu bulls be evaluated with the breed-specific minimum standards for scrotal circumference of 26 cm from 12 to 14 mo, 29 cm from 15 to 17 mo, and 30 cm from 18 to 20 mo of age.


Subject(s)
Cattle/physiology , Scrotum/anatomy & histology , Age Factors , Animals , Body Weight , Breeding , Cattle/genetics , Male , Reference Standards , Scrotum/physiology , Sperm Motility , Spermatozoa/physiology
8.
Phys Rev Lett ; 86(1): 39-42, 2001 Jan 01.
Article in English | MEDLINE | ID: mdl-11136088

ABSTRACT

The production of pions and kaons has been measured in 197Au+197Au collisions at beam energies from 0.6 to 1.5A GeV with the kaon spectrometer at SIS/GSI. The K+ meson multiplicity per nucleon is enhanced in Au+Au collisions by factors up to 6 relative to C+C reactions, whereas the corresponding pion ratio is reduced. The ratio of the K+ meson excitation functions for Au+Au and C+C collisions increases with decreasing beam energy. This behavior is expected for a soft nuclear equation-of-state.

9.
Phys Rev Lett ; 85(1): 18-21, 2000 Jul 03.
Article in English | MEDLINE | ID: mdl-10991148

ABSTRACT

The emission pattern of charged pions has been measured in Au+Au collisions at 1 GeV/nucleon incident energy. In peripheral collisions and at target rapidities, high-energy pions are emitted preferentially towards the target spectator matter. In contrast, low-energy pions are emitted predominantly in the opposite direction. The corresponding azimuthal anisotropy is explained by the interaction of pions with projectile and target spectator matter. This interaction with the spectator matter causes an effective shadowing which varies with time during the reaction. Our observations show that high-energy pions stem from the early stage of the collision whereas low-energy pions freeze out later.

10.
Reprod Fertil Dev ; 9(5): 545-9, 1997.
Article in English | MEDLINE | ID: mdl-9418985

ABSTRACT

The effects of angiotensin II (Ang II) as a semen extender were studied. In the first experiment, individual ejaculates from 10 bulls were split and extended in egg yolk citrate in the absence or presence of varying concentrations of Ang II (10[-5]-10[-10] M) to a final concentration of 35 x 10(6) sperm per mL. The percentage of intact acrosomes and percentage motility were determined in all treatments for all bulls at 0 h (immediately post thaw) and after incubation for 4 h at 37 degrees C. Extension of the semen with Ang II did not affect spermatozoal viability at either time studied. In the second experiment, mixed breed virgin heifers were induced into oestrus with intramuscular injections of prostaglandin F2alpha on Days 0 and 3. Animals that stood to be mounted were paired for bilateral intracornual insemination using a 0.5-mL French straw on each side approximately 8 h later. One of the paired heifers received semen containing Ang II (10[-5] M) while the other received control semen. A 1-mL aspirate of vaginal mucus was collected at hourly intervals for 8 h after insemination. Concentration of spermatozoa was determined by haemocytometry. There was a significant reduction in cumulative semen loss into the vagina of heifers inseminated with Ang II extended semen (14.4%) compared with heifers inseminated with control semen (19.7%). This suggests that Ang II, when added to extended semen, may reduce retrograde sperm loss following insemination without affecting sperm viability.


Subject(s)
Angiotensin II/pharmacology , Insemination, Artificial/veterinary , Semen/cytology , Sperm Motility/drug effects , Spermatozoa/drug effects , Animals , Cattle , Cohort Studies , Dose-Response Relationship, Drug , Female , Insemination, Artificial/standards , Male , Random Allocation , Semen/drug effects , Sperm Motility/physiology , Spermatozoa/physiology , Time Factors , Uterus/cytology
12.
J Anim Sci ; 73(7): 1914-9, 1995 Jul.
Article in English | MEDLINE | ID: mdl-7592073

ABSTRACT

The fertility of bull semen packaged in .25- and .5-mL french straws was compared. One ejaculate from each of five Holstein bulls was split, extended to 10 x 10(6) spermatozoa/inseminate dose in whole homogenized milk, packaged in .25- and .5-mL french straws, frozen in liquid nitrogen (LN) vapor, and stored in LN. Semen was thawed at 37 degrees C for 30 s. Synchronized heifers (n = 1,360) were inseminated (during a 12-mo period) with semen packaged in either a .25- or .5-mL french straw. Blood was collected on the day of insemination and the serum was assayed for progesterone. Heifers with blood progesterone levels of > 1 ng/mL were eliminated from the data. Blood was collected at 30 to 45 d after insemination and the serum was assayed for the presence of bovine pregnancy-specific protein B (bPSPB) by RIA to determine pregnancy. Conception was 63.6 and 62.0% (P = .55) for semen packaged in the .25- and .5-mL french straws, respectively. There was neither a bull x packaging unit interaction (P = .49) nor a day of insemination x packaging unit interaction (P = .87). Conception among bulls ranged from 57.1 to 68.0% (P = .19). No evidence was found that meteorological factors influenced conception. Under the conditions of this experiment, semen packaged in the .25- and .5-mL french straw had similar fertility.


Subject(s)
Cattle/physiology , Cryopreservation/veterinary , Fertility/physiology , Semen Preservation/veterinary , Semen/physiology , Animals , Cattle/blood , Cryopreservation/methods , Female , Fertilization/physiology , Insemination, Artificial/methods , Insemination, Artificial/standards , Insemination, Artificial/veterinary , Male , Progesterone/blood , Radioimmunoassay/veterinary , Semen Preservation/methods , Spermatozoa/physiology
13.
Theriogenology ; 43(3): 551-6, 1995 Feb.
Article in English | MEDLINE | ID: mdl-16727646

ABSTRACT

This study was conducted over a 12-mo period to determine the rate of bovine embryo death between 30 and 60 d of gestation. In addition, palpation per rectum as a means of pregnancy detection was evaluated as a possible cause of embryo death. Estrus was synchronized in Holstein heifers (n = 1358), weighing > or = 385 kg, with a single intramuscular injection of 25 mg prostaglandin F(2alpha). Estrus was primarily detected by the absence of paint marks on the tailhead. The heifers were artificially inseminated with semen from 5 Holstein sires. Blood was collected between 30 and 45 d after breeding, and sera were evaluated for the presence of bovine pregnancy-specific protein B (bPSPB) by RIA to determine pregnancy. Palpation for fetal membrane slip was conducted by an experienced technician in approximately one-half of the inseminated heifers. To determine embryonic survival, a second blood sample was collected at approximately 60 d from 862 heifers that were determined to be pregnant at the first blood sampling. Embryonic loss averaged 5.3% during the interval between the initial detection of pregnancy at 30 to 45 d and the subsequent detection of pregnancy at 60 d of gestation. Embryo loss in heifers that were palpated was 6.5% compared with that of 4.3% in the control heifers (X(2): P = 0.145). These findings establish that there was substantial loss of embryos between 30 and 60 d post breeding but that embryo loss was not affected by palpation per rectum.

14.
J Dairy Sci ; 77(9): 2745-53, 1994 Sep.
Article in English | MEDLINE | ID: mdl-7814743

ABSTRACT

The single most important problem limiting high reproductive efficiency in the national dairy herd is poor detection of estrus. Failure to detect estrus or erroneous diagnosis of estrus results in an estimated annual loss of over $300 million to the dairy industry in the US. New technologies for the solution of this problem must be more effective than visual observation and aids currently used to detect estrus. Ideally, technologies that provide the solution for detection problems should provide the following: continuous (24 h/d) surveillance of the cow, accurate and automatic identification of cows in estrus, operation for the productive lifetime of the cow, minimized labor requirements, and high accuracy in identifying the appropriate physiologic or behavioral events that correlate highly with ovulation. New approaches are aimed at providing automation of detection of estrus using electronic technology. Pedometry, implantable impedance sensors, and surface-applied and implantable pressure sensors are in various stages of development and use.


Subject(s)
Cattle , Estrus Detection/methods , Animals , Dairying/economics , Electric Impedance , Female , Motor Activity , Pressure
17.
Infect Immun ; 61(6): 2558-62, 1993 Jun.
Article in English | MEDLINE | ID: mdl-8500892

ABSTRACT

Sources of anti-Haemophilus somnus antibody in bovine uterine secretions following intramuscular immunization and subsequent intrauterine inoculation of killed H. somnus were investigated. Holstein cattle (n = 21) were immunized with a 270-kDa outer membrane protein from H. somnus (omp-270) by intramuscular injection. At estrus, the cattle were given an intrauterine inoculum of a heat-killed suspension of a homologous strain of H. somnus containing omp-270 (n = 7), a heterologous strain of H. somnus lacking omp-270 (n = 7), or phosphate-buffered saline (n = 7). Uterine secretions were sampled by saline lavage immediately prior to inoculation and at 6, 24, 48, 72, 96, and 120 h after inoculation. Immunoglobulin G subclass I (IgG1) and IgG2 antibody specific for omp-270 were detectable in estrous uterine secretions of all systemically immunized cattle from which an adequate sample was obtained. IgM antibody specific for omp-270 was detected in serum following immunization but was not consistently detected in the uterine secretions of any animal. IgA antibody specific for omp-270 was not detectable in either serum or uterine secretions following immunization or intrauterine inoculation. Ratios of antibody to immunoglobulin and ratios of immunoglobulin to albumin in serum and uterine secretions indicated that about half the IgG1 and essentially all the IgG2 in secretions originated in the serum. Relative titers of IgG1 and IgG2 omp-270-specific antibodies in the uterine lumen and serum gave no evidence for selective transport of either subclass from serum into local secretions. Neither heterologous nor homologous intrauterine inocula detectably altered the serum contribution to antibody in uterine secretions within the sampling period. On the basis of these results, development of a systemic IgG2 antibody response may provide the basis for local immunological protection in the bovine reproductive tract.


Subject(s)
Antibodies, Bacterial/analysis , Bacterial Outer Membrane Proteins/immunology , Haemophilus/immunology , Uterus/immunology , Animals , Antibodies, Bacterial/blood , Antibody Specificity , Cattle , Female , Immunization , Immunoglobulin G/analysis , Immunoglobulin G/blood , Injections, Intramuscular , Serum Albumin/analysis , Uterus/metabolism
19.
J Reprod Fertil ; 93(2): 341-5, 1991 Nov.
Article in English | MEDLINE | ID: mdl-1787453

ABSTRACT

Polymorphonuclear neutrophils (PMN) in bovine uterine flushings following intrauterine deposition of killed bacteria were measured and the effect of immune status on the influx of PMN into the uterine lumen during oestrus was determined. Holstein heifers were immunized with a 270-kDa outer-membrane protein (omp-270) from Haemophilus somnus. During oestrus, immunized heifers (n = 21) received an intrauterine inoculum of either a heat-killed suspension of a homologous strain of H. somnus containing omp-270 (n = 7), a heterologous strain of H. somnus lacking omp-270 (n = 7), or phosphate-buffered saline (n = 7). Five additional heifers were inseminated with extended bovine semen. Uterine contents were collected in saline lavage immediately before inoculation (t0) and at 6, 24, 48, 72, 96, and 120 h after inoculation. The semen-inoculated heifers were lavaged only at t120. All groups experienced PMN infiltration which peaked 6 h after inoculation and tended to decline thereafter. Differences were not observed between treatment groups, indicating that neither bacterial inoculation nor immune status was as important in eliciting PMN effusion as the flushing procedure itself.


Subject(s)
Bacterial Vaccines/administration & dosage , Estrus/immunology , Haemophilus/immunology , Neutrophils/physiology , Uterus/immunology , Animals , Cattle , Cell Movement/physiology , Female , Kinetics
20.
J Anim Sci ; 69(10): 3999-4006, 1991 Oct.
Article in English | MEDLINE | ID: mdl-1778813

ABSTRACT

The objective of this experiment was to determine whether sexually experienced bulls would demonstrate a preference (using primarily olfaction) between a heifer in estrus and a heifer in diestrus (luteal phase) when physical contact was denied. In Exp. 1, a heifer in estrus and a heifer in diestrus (n = 18 pairs) were individually enclosed in opposite ends of a pen. During each period (n = 18), three bulls were individually introduced into the pen and allowed 5 min to demonstrate preference between the heifer in estrus and the heifer in diestrus. The total time that a bull spent within 2.5 m of either heifer was used to evaluate his preference. The total time that bulls spent adjacent to the heifer in estrus was not greater (P greater than .05) than the total time that bulls spent adjacent to the heifer in diestrus. In Exp. 2, five bulls were used and were evaluated using the same method as in Exp. 1. In addition, the number of flehmen reactions were recorded for each bull. Six heifers were ovariectomized and each heifer was induced into estrus with one of three doses of estradiol 17 beta (5, 10, and 20 mg) over the 5-wk treatment period. Estradiol 17 beta-treated heifers were always paired with a non-estradiol-treated (control) heifer. The goal of Exp. 2 was to determine whether heifers treated with pharmacological doses of estradiol 17 beta would be preferentially selected from non-estradiol-treated (control) heifers by bulls.(ABSTRACT TRUNCATED AT 250 WORDS)


Subject(s)
Cattle/physiology , Diestrus , Estrus , Sexual Behavior, Animal , Animals , Crosses, Genetic , Estradiol/blood , Estradiol/pharmacology , Female , Male , Odorants , Progesterone/pharmacology
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