Refinar búsqueda
Resultados 1-10 de 12
Alterations in pregnancy-associated glycoprotein concentrations of pregnant sheep experimentally infected with bovine viral diarrhea virus
2021
Lear, Andrew | Pohler, Ky | Sula, Mee-Ja M. | Kiupel, Matti | Mulon, Pierre-Yves | Caldwell, Marc
OBJECTIVE To compare pregnancy-associated glycoprotein 1 (PAG1) concentrations in maternal (jugular vein) and fetal (uterine vein) circulations and amniotic fluid samples between pregnant ewes that were and were not experimentally infected with bovine viral diarrhea virus (BVDV). ANIMALS 11 healthy pregnant yearling ewes. PROCEDURES Before study initiation, all ewes were naïve to BVDV and confirmed pregnant by transabdominal ultrasonography at approximately 60 days of gestation. At 65 days of gestation, ewes were intranasally inoculated with a noncytopathic BVDV type 1b strain (concentration, 107 TCID50/mL; 2 mL/nostril; n = 6) or an equal volume of BVDV-free viral culture medium (control; 5). A blood sample was collected for measurement of PAG1 concentration before inoculation. At 80 days of gestation, each ewe was anesthetized and underwent an ovariohysterectomy. While sheep were anesthetized, blood samples from the jugular and uterine veins and an amniotic fluid sample were collected for measurement of PAG1 concentration. Fetal tissues underwent real-time PCR analysis for BVDV RNA, and placental specimens underwent histologic evaluation and immunohistochemical staining for BVDV antigen. RESULTS At 80 days of gestation, BVDV RNA in fetal tissues and mild placentitis were detected in 5 of 6 BVDV-inoculated ewes. Mean PAG1 concentrations in the maternal and fetal circulations of BVDV-inoculated ewes were significantly less than those in control ewes. Mean amniotic fluid PAG1 concentration did not differ significantly between the 2 groups. CONCLUSIONS AND CLINICAL RELEVANCE Concentration of PAG1 in the maternal circulation may be a useful biomarker for determining placental health in sheep after viral infection of the reproductive tract.
Mostrar más [+] Menos [-]Effect of oral administration of meloxicam prior to transport on inflammatory mediators and leukoctye function of cattle at feedlot arrival
2017
Capik, Sarah F. | White, Brad J. | Larson, Robert L. | Van Engen, Nicholas | Cernicchiaro, Natalia | Engelken, Terry J. | Lakritz, Jeffrey | Ballou, Michael A. | Hulbert, Lindsey E. | Vann, Rhonda C. | Caswell, Jeff L. | Jacob, Gabriella | Carroll, Jeffery A. | Coetzee, Johann F.
OBJECTIVE To investigate the effects of meloxicam administration before long-distance transport on inflammatory mediators and leukocyte function of cattle at feedlot arrival. ANIMALS 60 healthy yearling beef steers. PROCEDURES Single-source steers were assigned to a transported (n = 40) or nontransported (20) group. Then, half of the steers within each group were assigned to receive meloxicam (1 mg/kg, PO) or a lactose placebo (1 bolus/steer, PO). All steers were transported approximately 1,300 km overnight to a feedlot; however, the nontransported group was moved before treatment (meloxicam or placebo) administration and allowed a 17-day acclimation period, whereas the transported group was moved immediately after treatment administration on day −1. Blood samples for measurement of inflammatory mediators and leukocyte function were collected from all steers on days −1, 0, and 3. RESULTS For steers that received meloxicam, mean plasma meloxicam concentration for the transported group was significantly greater than that for the nontransported group on day 0. For steers that received the placebo, mean haptoglobin-matrix metalloproteinase-9 complex for the transported group was significantly greater than that for the nontransported group on day 0. Mean haptoglobin concentration, neutrophil L-selectin intensity, and polymorphonuclear leukocyte count for the transported group were significantly greater than those for the nontransported group. Mean substance P concentration for nontransported steers that received meloxicam was significantly lower than that for the other 3 treatment groups. CONCLUSIONS AND CLINICAL RELEVANCE Results indicated meloxicam administration to healthy steers immediately before long-distance transport did not significantly mitigate the effects of transport-induced stress on leukocyte function or inflammatory markers.
Mostrar más [+] Menos [-]Evaluation of pathogen-specific biomarkers for the diagnosis of tuberculosis in white-tailed deer (Odocoileus virginianus)
2017
Wanzala, Sylvia I. | Palmer, Mitchell V. | Waters, Wade R. | Thacker, Tyler C. | Carstensen, Michelle | Travis, Dominic A. | Sreevatsan, Srinard
OBJECTIVE To develop a noninvasive biomarker-based detection system specific for Mycobacterium bovis for monitoring infection in wild animals. SAMPLE Serum samples from 8 experimentally infected yearling white-tailed deer (Odocoileus virginianus) and 3 age-matched control deer and from 393 Minnesota Department of Natural Resources hunter-harvested white-tailed deer in northwest Minnesota. PROCEDURES 8 yearling deer were inoculated with 2 × 10(8) CFUs of virulent M bovis strain 1315 (day 0), and sera were obtained on days 0, 19, 48, and 60; sera were obtained from 3 uninoculated control deer on those same days. Sera from these deer and 9 M bovis-positive hunter-harvested deer were tested for 3 Mycobacterium-specific biomarkers (MB1895c, MB2515c, and polyketide synthase 5) by use of an indirect ELISA. That same ELISA was used to test sera obtained from 384 exposed noninfected deer in northwest Minnesota from 2007 through 2010, concurrent with an outbreak of tuberculosis involving cattle and deer in that region. RESULTS ELISA results revealed that tuberculosis infection could be detected as early as 48 days after inoculation in experimentally infected deer. Results for 384 deer sera revealed that prevalence of tuberculosis decreased over the 4-year period. CONCLUSIONS AND CLINICAL RELEVANCE Results suggested that the prevalence of tuberculosis in Minnesota deer decreased after 2009 but tuberculosis may have persisted (as subclinical disease) at extremely low levels, as indicated by the presence of low concentrations of circulating biomarkers. Biomarker-based diagnostic tests may offer a specific approach for early identification of M bovis infection.
Mostrar más [+] Menos [-]Associations between yearling exercise and interruptions during race training in Thoroughbred racehorses
2012
Bolwell, Charlotte F. | Rogers, Christopher W. | French, Nigel P. | Firth, Elwyn C.
Objective: To investigate the effect of exercise during yearling sales preparation on the risk of interruptions during training in Thoroughbred racehorses. Animals: 114 Thoroughbred racehorses. Procedures: Information regarding the daily exercise of yearlings during sales preparation was obtained prospectively from a convenience sample of stud farms. Yearlings were followed to entry into race training, and subsequently, daily training information was recorded until the end of the racing season. Competing-risks survival analysis was used to model time from entry into race training to voluntary training interruption (no known condition or disease identified) and time from entry into race training to involuntary training interruption (due to presence of a condition or disease) occurring before the first trial (practice race for education). Total hand walking time and mechanical walker time accumulated during sales preparation were the main exposures of interest. Results: 82 of 114 (71.9%) horses had an interruption before the first trial; 65 (79%) interruptions were voluntary, and 17 (21 %) interruptions were involuntary. Increased total hand walking time was significantly associated with decreased risk of voluntary interruptions, whereas longer cumulative distances at a canter were significantly associated with decreased risk of involuntary interruptions. Conclusions and Clinical Relevance: Results identified an association between early exercise during sales preparation and decreased risk of voluntary interruption and increased risk of involuntary interruption during training of 2-year-old Thoroughbred racehorses. Further investigation into the effects of early exercise on racing performance is needed, but results have indicated that there may be an opportunity to modify early exercise programs.
Mostrar más [+] Menos [-]Serologic evidence of vesivirus-specific antibodies associated with abortion in horses. [Erratum: 2006 July, v. 67, no. 7, p. 1265.]
2006
Kurth, A. | Skilling, D.E. | Smith, A.W.
Objective-To test horses for serologic evidence of an association between vesiviral antibodies and abortion. Sample Population-Sera from 141 horses. Procedures-2 experiments were conducted. Experiment 1 comprised sera obtained in 2001 and 2002 from 3 groups of horses (58 mares from farms with a history of abortion problems, 25 mares between 3 and 13 years of age with unknown reproductive histories that were sold at auction breeding-age control mares, and 29 mixed-age males and yearling females sold at auction negative control population). Experiment 2 comprised sera from 3 groups of pregnant mares (10 pregnant mares fed Eastern tent caterpillars ETCs, 9 pregnant mares fed ETC frass only, and 10 pregnant control mares). Sera were analyzed for antibodies against vesivirus by use of a validated recombinant vesivirus-specific peptide antigen in an indirect ELISA. Results-For experiment 1, 37 of 58 (63.8%) mares from farms with abortion problems were seropositive for vesivirus antibodies, whereas 10 of 25 (40%) breeding-age control mares were seropositive. All 29 mixed-age males and yearling females were seronegative for vesivirus antibodies. For experiment 2, 17 of 29 mares aborted (some from each group). Seropositive status for vesivirus antibodies increased from 47.1% (8/17) to 88.2% (15/17) for the pregnant mares that aborted during the experiment. Conclusion and Clinical Relevance-Significant association was detected between seropositive status for vesivirus and abortion in mares; consequently, vesivirus appears to be a pathogenic virus associated with abortion in mares. These data support adding vesivirus antibody testing into diagnostic screening to determine the cause for abortion in mares.
Mostrar más [+] Menos [-]Effects of initial handling and training on autonomic nervous function in young Thoroughbreds
2002
Ohmura, Hajime | Hiraga, Atsushi | Aida, Hiroko | Kuwahara, Masayoshi | Tsubone, Hirokazu
Objective-To determine the effects of initial handling and training on autonomic nervous functions in young Thoroughbreds. Animals-63 healthy Thoroughbreds. Procedure-All horses were trained to be handled and initially ridden in September of the yearling year and then trained until the following April by conventional training regimens. To obtain the heart rate (HR), electrocardiograms were recorded in the stable before initial handling and training and following 7 months of training; variations in HR were then evaluated from the power spectrum in terms of the low frequency (LF; 0.01 to 0.07 Hz) power and high frequency (HF; 0.07 to 0.6 Hz) power as indices of autonomic nervous activity. To evaluate the fitness, the V200 (velocity at HR of 200 beat/min), which is reflective of the aerobic capacity of the horse, was measured. Results-Mean (+/- SE) resting HR decreased significantly from 41.5 +/- 0.8 to 38.7 +/- 0.4 beat/min following 7 months of training. The LF power of horses increased significantly from 1,037 +/- 128 milliseconds2 in September of the yearling year to 2,944 +/- 223 milliseconds2 in the following April. Similarly, the HF power increased significantly from 326 +/- 30 milliseconds2 to 576 +/- 39 milliseconds2 at the corresponding time points. The V200 increased significantly following training. Conclusions and Clinical Relevance-Increases in LF and HF powers indicate that parasympathetic nervous activity increases in horses by 7 months of training. The decrease in resting HR may be dependent on the training-induced increase of parasympathetic nervous activity in Thoroughbreds.
Mostrar más [+] Menos [-]Retrograde catheterization of the urinary bladder in healthy male goats by use of angiographic catheters
2016
Reppert, Emily J. | Streeter, Robert N. | Simpson, Katharine M. | Taylor, Jared D.
OBJECTIVE To identify and evaluate 3 types of angiographic catheters for retrograde urinary bladder catheterization in healthy male goats. ANIMALS 12 sexually intact yearling Alpine-cross bucks. PROCEDURES Three 5F angiographic catheters of the same length (100 cm) and diameter (0.17 cm) but differing in curvature at the tip were labeled A (straight tip), B (tip bent in 1 place), and C (tip bent in 2 places). During a single anesthetic episode, attempts were made to blindly pass each catheter into the urinary bladder of each goat. Order of catheters used was randomized, and the veterinarian passing the catheter was blinded as to catheter identity. The total number of attempts at catheter passage and the total number of successful attempts were recorded. RESULTS Catheter A was unsuccessfully passed in all 12 goats, catheter B was successfully passed in 8 goats, and catheter C was successfully passed in 4 goats. The success rate for catheter B was significantly greater than that for catheter A; however, no significant difference was identified between catheters B and C or catheters A and C. CONCLUSIONS AND CLINICAL RELEVANCE 2 angiographic catheters were identified that could be successfully, blindly advanced in a retrograde direction into the urinary bladder of healthy sexually intact male goats. Such catheters may be useful for determining urethral patency, emptying the urinary bladder, and instilling chemolysing agents in goats with clinical obstructive urolithiasis.
Mostrar más [+] Menos [-]Computed tomographic evaluation to determine efficacy of euthanasia of yearling feedlot cattle by use of various firearm-ammunition combinations
2013
Thomson, Daniel U. | Wileman, Benjamin W. | Rezac, Darrel J. | Miesner, Matt D. | Johnson-Neitman, Jennifer L. | Biller, David S.
Objective—To evaluate with CT the efficacy of various combinations of firearms and ammunitions to penetrate and disrupt the brain tissue of cadaveric heads of feedlot steers. Sample—42 fresh cadaveric heads of 12- to 18-month-old Bos taurus steers. Procedures—For each of 7 combinations of firearms and ammunitions (.22-caliber rifle firing a long rifle 30-grain plated lead solid- or hollow-point round, .223-caliber carbine firing a 50-grain ballistic-tip round, 9-mm pistol firing a 124-grain total metal jacket round, .45-caliber automatic Colt pistol [ACP] firing a 230-grain full metal jacket round, and 12-gauge shotgun firing a 2.75-inch 1.25-ounce No. 4 birdshot shell or a 1-ounce rifled slug), 6 cadaveric heads were shot at an identical distance (3 m), angle, and anatomic location. Heads were scanned with third-generation CT, and images were evaluated to determine extent of penetration, projectile fragmentation, cranial fracture, and likelihood of instantaneous death (≥ 30% destruction of brain tissue or a brainstem lesion). Results—41 of 42 skulls were penetrated by the projectile. Instantaneous death was considered a likely consequence for 83% (25/30) of heads shot with a rifle-fired .22-caliber solid-point round, pistol-fired .45-caliber ACP round, carbine-fired .223-caliber round, and shotgun-fired birdshot and slug. Of the 18 heads shot with pistol-fired 9-mm and .45-caliber ACP rounds and rifle-fired .22-caliber hollow-point rounds, only 6 had brainstem lesions. Conclusions and Clinical Relevance—Results suggested that gunshots delivered by all firearm-ammunition combinations except rifle-fired .22-caliber hollow-point rounds and pistol-fired 9-mm rounds were viable options for euthanasia of feedlot cattle.
Mostrar más [+] Menos [-]Developmental regulation of the activation of translation initiation factors of skeletal muscle in response to feeding in horses
2012
Wagner, Ashley L. | Urschel, Kristine L.
Objective: To determine whether feeding-induced activation of translation initiation factors, specifically protein kinase B, ribosomal protein S6 kinase (S6K1), ribosomal protein S6 (rpS6), and eukaryotic initiation factor 4E binding protein 1, in horses is affected by age. Animals: 6 yearlings, six 2-year-old horses, and 6 mature horses. Procedures: After an 18-hour period of feed withholding, horses consumed a high-protein meal (2 g/kg) at time 0 and 30 minutes (postprandial state) or continued to have feed withheld (postabsorptive state). Blood samples were collected for the duration of the experimental procedures and used to determine plasma concentrations of glucose, insulin, and amino acids. At 90 minutes, biopsy specimens were collected from a gluteal muscle and used to measure phosphorylation of translation initiation factors. Results: Plasma glucose, insulin, and amino acid concentrations were elevated for the postprandial state, compared with results for the postabsorptive state, regardless of age. Phosphorylation of protein kinase B, S6K1, rpS6, and eukaryotic initation factor 4E binding protein 1 was increased for the postprandial state. There was an effect of age with increased phosphorylation of S6K1 at Thr389 and rpS6 at Ser235/236 in the yearlings and mature horses, compared with results for the 2-year-old horses. Conclusions and Clinical Relevance: Food consumption resulted in an increase in the activation of translation initiation factors, with the highest degree of responsiveness in the yearlings. This indicated that increased muscle accretion seen during growth could be a result of increased rates of muscle protein synthesis in response to a meal stimulus.
Mostrar más [+] Menos [-]Polymerase chain reaction-restriction fragment length polymorphism analysis of the SzP gene of Streptococcus zooepidemicus isolated from the respiratory tract of horses
2002
Anzai, Toru | Timoney, John F. | Kuwamoto, Yasushi | Ryuichi, Wada | Oikawa, Msaaki | Higuchi, Tohru
Objective-To develop polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) analysis for molecular typing of strains of Streptococcus zooepidemicus and to use the new typing method to analyze a collection of isolates from the respiratory tract of Thoroughbreds. Sample Population-10 strains of S zooepidemicus, 65 isolates from the respiratory tract of 9 yearlings following long distance transportation, and 89 isolates from tracheal aspirates of 20 foals with pneumonia. Procedure-Phenotypic variations in the SzP protein were detected by western immunoblot analysis. Using PCR-RFLP analysis, genotypes were obtained with primer sets from the SzP gene, followed by restriction endonuclease digestion of the amplicons. Results-Unique genotypic patterns were obtained with a primer set designed from both ends of the structural gene and the restriction endonuclease Dde I. Forty-five isolates from the lymphoid tissue within the pharyngeal recess (ie, pharyngeal tonsil) of yearlings included 10 SzP genotypes and SzP phenotypes. Isolates from the trachea of each yearling were of a single genotype that was also present among isolates from the pharyngeal tonsil of the same horses. Isolates from tracheal aspirates of foals belonged to 14 genotypes. Conclusion and Clinical Relevance-Analysis of the SzP gene by use of PCR-RFLP was effective for molecular typing of strains of S zooepidemicus in the study of respiratory tract disease in horses. Results of PCR-RFLP analysis indicate that a single strain of S zooepidemicus can migrate from the pharyngeal tonsil to the trachea at a high rate in horses undergoing long distance transportation.
Mostrar más [+] Menos [-]