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241.
Taylor D. Stephens Ryan M. Brooks Julia L. Carrington Lulu Cheng Anne C. Carrington Cheryl A. Porr Rebecca K. Splan 《Journal of Equine Veterinary Science》2013
Frozen semen provides several advantages to the breeder relative to fresh or cooled semen. However, some stallions are undesirable candidates for semen freezing due to poor post-thaw motility or longevity caused by membrane damage, osmotic stress, and oxidative stress during cryopreservation. The objective of this study was to determine the effect of post-thaw addition of pentoxifylline, caffeine, or taurine on sperm motility and longevity in equine frozen semen. Pentoxifylline, caffeine, or taurine was incorporated immediately into thawing frozen semen from nine warmblood stallions. Spermatozoa motility and longevity parameters were recorded and analyzed for each additive and for an untreated control. Of the three additives, only pentoxifylline improved total and progressive semen motility relative to that of untreated control. Pentoxifylline also increased semen curvilinear velocity, average path velocity, and straight line velocity relative to those of caffeine, taurine, or control. Semen treated with pentoxifylline also showed greater longevity relative to that of caffeine- or taurine-treated or untreated semen. Taurine improved linearity in comparison to that of semen treated with pentoxifylline, caffeine, or control but did not improve other parameters. Pentoxifylline may be useful in enhancing the quality of equine frozen semen and therefore improving its fertility. Additional studies are warranted that examine the effect of these additives on the conception rate. Pentoxifylline can be used to increase motility and longevity of equine frozen semen and theoretically increase probability of conception and overall breeding success rates. 相似文献
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243.
Stephens BB Gurney KR Tans PP Sweeney C Peters W Bruhwiler L Ciais P Ramonet M Bousquet P Nakazawa T Aoki S Machida T Inoue G Vinnichenko N Lloyd J Jordan A Heimann M Shibistova O Langenfelds RL Steele LP Francey RJ Denning AS 《Science (New York, N.Y.)》2007,316(5832):1732-1735
Measurements of midday vertical atmospheric CO2 distributions reveal annual-mean vertical CO2 gradients that are inconsistent with atmospheric models that estimate a large transfer of terrestrial carbon from tropical to northern latitudes. The three models that most closely reproduce the observed annual-mean vertical CO2 gradients estimate weaker northern uptake of -1.5 petagrams of carbon per year (Pg C year(-1)) and weaker tropical emission of +0.1 Pg C year(-1) compared with previous consensus estimates of -2.4 and +1.8 Pg C year(-1), respectively. This suggests that northern terrestrial uptake of industrial CO2 emissions plays a smaller role than previously thought and that, after subtracting land-use emissions, tropical ecosystems may currently be strong sinks for CO2. 相似文献
244.
Dinnebier RE Gunnarsson O Brumm H Koch E Stephens PW Huq A Jansen M 《Science (New York, N.Y.)》2002,296(5565):109-113
CHCl3 and CHBr3 intercalated C60 have attracted particular interest after a superconductivity transition temperature (Tc) of up to 117 K was discovered. We have determined the structure using synchrotron x-ray powder-diffraction and found that the expansion of the lattice mainly takes place in one dimension (triclinic b axis), leaving planes of C60 molecules on an approximately hexagonal, slightly expanded lattice. We have performed tight-binding band structure calculations for the surface layer. In spite of the slight expansion of the layers, for the range of dopings where a large Tc has been observed, the density of states at the Fermi energy is smaller for C60.2CHCl3 and C60.2CHBr3 than for C60. This suggests that the lattice expansion alone cannot explain the increase of Tc. 相似文献
245.
Irizarry-Rovira AR Stephens J Christian J Kjemtrup A DeNicola DB Widmer WR Conrad PA 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2001,30(4):180-188
Abstract: A 10-year-old spayed female mixed-breed dog was presented to the Purdue University Veterinary Teaching Hospital (PUVTH) with complaints of persistent anemia with occasional exacerbations, anorexia, and lethargy. The dog had been presented to the referring veterinarian 2 months prior with multiple bite wounds received during a fight with 3 Pit Bull Terriers. The dog was discharged after the wounds were cleaned and surgically closed. Upon admission to the PUVTH, blood was collected for a complete blood count and biochemical analysis. Microscopic examination of peripheral blood smears revealed intraerythrocytic protozoal parasites consistent with Babesia gibsoni . Molecular analysis confirmed that the organism was B gibsoni and that its 18S ribosomal RNA sequence was identical to that of other B gibsoni isolates from Oklahoma, North Carolina, and Okinawa, Japan. Hematologic changes included moderately severe, regenerative, macrocytic, normochromic anemia, with poikilocytosis, polychromasia, anisocytosis, and a marked increase in nucleated RBCs. Biochemical changes included increased serum alanine aminotransferase, alkaline phosphatase, and gamma glutamyl-transferase activities. The dog was treated with imidocarb, but despite initial clinical improvement, the dog died 2 weeks after the first dose. A necropsy was not performed. The infection in this dog is the first reported case of B gibsoni infection in Indiana. Because of the widespread geographical distribution of the organism, veterinarians and veterinary clinical pathologists throughout the United States should carefully examine Romanowsky-stained blood smears from patients with acute hemolytic anemia for small intraerythrocytic babesial parasites. 相似文献
246.
SUMMARY: Case records of 450 horses with signs of neurological disease are reviewed. One hundred and nineteen horses with neurological disease due to trauma were examined, of which 60 were due to spinal cord trauma, 47 to brain or cranial nerve trauma and 12 to peripheral nerve trauma. Cervical vertebral fractures/trauma were the most common injury. Basisphenold/basloccipital bone fractures were the most common form of cranial trauma and facial nerve paralysis the most common cranial nerve injury. Eighty-nine horses with neurological disease due to malformation were examined. Cervical vertebral malformation occurred in 83 horses and congenital defects in 6 foals. Neurological disease due to inflammation or infection occurred in 30 horses. The most common disease of this type was meningitis, which occurred in 11 horses and foals. Neoplasms in the CNS caused neurological disease in 8 horses. The final category was miscellaneous neurological disease, which was diagnosed in 204 horses. Diseases in this category included neonatal (28 cases), toxic/metabolic (27 cases), idiopathic (133 cases), degenerative (3 cases) and other neurological diseases (13 cases). The most common condition was idiopathic laryngeal hemiplegia (116 cases).
Where possible, diagnosis relied on a thorough neurological examination with use of ancillary tests in selected cases including rhinolaryngoscopy, radiography, myelography, ophthalmoscopy and cerebrospinal fluid analysis when indicated. In many cases necropsy and histopathological confirmation or diagnosis was necessary. 相似文献
Where possible, diagnosis relied on a thorough neurological examination with use of ancillary tests in selected cases including rhinolaryngoscopy, radiography, myelography, ophthalmoscopy and cerebrospinal fluid analysis when indicated. In many cases necropsy and histopathological confirmation or diagnosis was necessary. 相似文献
247.
Crisp D McMuldroch S Stephens SK Sinton WM Ragent B Hodapp KW Probst RG Doyle LR Allen DA Elias J 《Science (New York, N.Y.)》1991,253(5027):1538-1541
Near-infrared images of Venus, obtained from a global network of ground-based observatories during January and February 1990, document the morphology and motions of the night-side near-infrared markings before, during, and after the Galileo Venus encounter. A dark cloud extended halfway around the planet at low latitudes (>+/-40 degrees ) and persisted throughout the observing program. It had a rotation period of 5.5 +/- 0.15 days. The remainder of this latitude band was characterized by small-scale (400 to 1000 kilometers) dark and bright markings with rotation periods of 7.4 +/- 1 days. The different rotation periods for the large dark cloud and the smaller markings suggests that they are produced at different altitudes. Mid-latitudes (+/-40 degrees to 60 degrees ) were usually occupied by bright east-west bands. The highest observable latitudes (+/-60 degrees to 70 degrees ) were always dark and featureless, indicating greater cloud opacity. Maps of the water vapor distribution show no evidence for large horizontal gradients in the lower atmosphere of Venus. 相似文献
248.
M. S. Smith N. J. Booth W. S. Stephens C. A. Goudie B. A. Simco 《Journal of aquatic animal health》2015,27(3):152-155
The ability of the anesthetics metomidate hydrochloride and tricaine methanesulfonate (MS-222) to mitigate the cortisol stress response of Channel Catfish Ictalurus punctatus was evaluated during a 10-min confinement stress. The cortisol concentrations of Channel Catfish anesthetized in metomidate hydrochloride remained consistent throughout the 10-min exposure; however, for fish anesthetized with MS-222 and nonanesthetized fish, cortisol concentrations were approximately 7- and 22-fold higher, respectively, than the baseline concentrations. While both anesthetics reduced cortisol concentrations relative to those of nonanesthetized fish, these results suggest that MS-222 is an appropriate anesthetic to use during the initial 5 min of sedation and that metomidate hydrochloride is appropriate for longer periods of sedation.
Received November 18, 2014; accepted April 9, 2015 相似文献
249.
250.
DR THOMPSON D. RUGG PG SCOTT LG CRAMER† RA BARRICK† 《Australian veterinary journal》1994,71(6):161-164
SUMMARY An ivermectin-based jetting fluid was assessed for its efficacy in the prevention of blowfly strike and treatment of lice in long-wooled sheep. The ivermectin concentrate was diluted to 0.03 mg/mL and applied via a standard hand jetting technique. In insectary studies, using laboratory-reared Lucilia cuprina, sheep jetted with ivermectin were protected from induced breech and body strikes for 18 weeks after treatment. Merino and Corriedale sheep were equally protected, as were sheep subjected to 25 mm simulated rainfall at 1, 3 or 6 hours after jetting. Naturally occurring infestations of lice, Bovicola (Damalinia) ovis, were successfully treated with ivermectin jetting fluid in Merino and Corriedale sheep using a standard hand jetting technique. In addition, the efficacy of treatment was not affected by simulated rainfall at 1, 3 or 6 hours after treatment. 相似文献