bluuebunny/crossref_metadata_2025_split huggingface dataset:
Biomechanical study of the effect of coxofemoral positioning on passive hip joint laxity in dogs
Authors: Heyman Steven J. , Smith Gail K. , Cofone Mark A. 
Published: January 2024

SUMMARY
Ten coxofcmoral joints from 5 dog cadavers were used to study the effect of coxofcmoral positioning on passive hip laxity. A material test system was used to measure lateral translation when force was between 20 N of compression and 40 N of distraction. Using the orthogonal coordinate system imposed in this study, neutral position was empirically defined at 15° of extension and 10° of abduction, relative to the plane of the pelvis, and no internal or external rotation of the femur. The hips were mounted in a custom-designed jig that allowed 1 rotational degree of freedom (ie, either flexion extension, adduction/ abduction, or internal/external rotation), while holding the other 2 constant. Lateral translation of the hips was tested at 10° intervals from 30° of flexion to 70° of extension, 40° of adduction to 60° of abduction, and 30° of internal rotation to 40° of external rotation. Lateral displacement was maximal at 10° of extension, 20° of abduction, and 10° of external rotation, approximating the neutral coxofcmoral position during stance. As the hips were rotated into extreme positions, the amount of lateral displacement occurring with the same applied load decreased significantly to 32.0 to 65.3% of the maximal displacement. Determining the position of the hip associated with maximal passive laxity in vitro is essential to the design of a precise and accurate clinical stress-radiographic method to quantitate joint laxity in dogs. Our results confirm earlier work that passive hip joint laxity is at a maximum with the hip approximately in a neutral weight-bearing position.
Dose-response relation between plasma concentrations of corticotropin and Cortisol after administration of incremental doses of cosyntropin for corticotropin stimulation testing in cats
Authors: Peterson Mark E. , Kemppainen Robert J. 
Published: January 2024

SUMMARY
We compared the plasma Cortisol and immunoreactive corticotropin (IR-ACTH) responses to incremental doses (1.25, 12.5 and 125 μg) of synthetic ACTH (cosyntropin) administered IV to 6 clinically normal cats. Mean plasma Cortisol concentration increased significantly (P < 0-0001) after administration of all 3 doses of cosyntropin. After administration of the 1.25- and 12.5-μg doses, plasma Cortisol concentration peaked at 30 minutes, then decreased to values not significantly different from baseline concentration by 90 and 120 minutes, respectively. In contrast, after administration of the 125-μg dose, mean Cortisol concentration peaked at 60 minutes and remained significantly (P < 0.05) higher than baseline values at 120 minutes. Compared with the 1.25- and 12.5-μg doses, administration of the 125-μg dose of cosyntropin induced significantly (P < 0.05) higher Cortisol responses at 60, 90, and 120 minutes. Although individual cat's peak plasma Cortisol concentration after administration of the 125-μg dose was higher than the peak value determined after administration of the 2 lower doses of cosyntropin, these differences were not statistically significant. Mean plasma IR-ACTH concentration increased significantly (P < 0.0001) and reached a maximal value at 30 minutes after administration of all 3 doses of cosyntropin. After administration of the 1.25- and 12.5-μg doses, plasma IR-ACTH concentration decreased to values not significantly different from baseline concentration by 60 and 120 minutes, respectively, whereas mean IR-ACTH concentration remained significantly (P < 0.05) higher than baseline values 120 minutes after administration of the 125-μg dose. Mean peak plasma IR-ACTH concentration attained after administration of the 125-μg dose of cosyntropin was significantly higher than that attained after administration of the 2 lower doses. Peak plasma IR-ACTH concentration attained after administration of the 12.5-μg dose of cosyntropin was significantly higher than that attained after administration of 1.25 μg of cosyntropin. Results of the study indicate that IV administration of cosyntropin at doses ranging from 1.25 to 125 μg induces similar peak plasma cortisol responses in clinically normal cats, indicating that all of the doses may maximally stimulate the adrenal cortex. Administration of the higher cosyntropin doses did, however, result in more prolonged adrenocortical response.
Changes in fluid composition on the serosal surface of jejunum and small colon subjected to venous strangulation obstruction in ponies
Authors: Ruggles Alan J. , Freeman David E. , Acland Helen M. , Simmons Marie Fitz 
Published: January 2024

SUMMARY
In 6 anesthetized ponies, 3 segments of jejunum and 3 segments of small colon were isolated from the peritoneal cavity in plastic bags filled with Hanks' balanced salt solution. One jejunal and 1 small colon segment were subjected to venous strangulation obstruction for 3 hours (vso-3), venous strangulation obstruction for 6 hours (vso-6), or a 6-hour sham procedure to control for changes induced by isolation in a plastic bag. Additional segments of jejunum and colon that were not placed in bags served as controls for histologic examination and collagenase measurements. Samples of fluid surrounding the intestine were obtained for chemical analyses, nucleated cell count, aerobic and anaerobic bacteriologic culture, and measurement of collagenase activity. Full-thickness tissue samples were obtained for histologic examination and measurement of collagenase content.
Bacteria did not cross the intestinal wall after 3 and 6 hours of vso, despite severe mucosal lesions in these segments. At 6 hours, Po2 was significantly less and Pco2 was significantly (P<0.05) greater in the fluid surrounding the vso-6 jejunal segments, compared with the sham jejunal segments. The pH was significantly (P<0.05) less in fluid surrounding vso-6 small colon segments, compared with the sham colon segments at 6 hours. For jejunum and small colon, phosphate and lactate concentrations were significantly (P<0.05) greater in vso-6 fluid than in the corresponding sham fluids at 6 hours. Fibrin formed around all vso segments, although fibrinogen was not detected in the surrounding fluid, indicating possible rapid conversion of fibrinogen to fibrin. Fluid collagenase activity increased significantly (P<0.05) in all segments over 6 hours. The preparation used in this study was successful in measuring local changes on the serosal surface of intestine subjected to vso and in isolating segments under study in a sterile environment.
Vertical ground reaction force distribution during experimentally induced acute synovitis in dogs
Authors: Rumph Paul F. , Kincaid Steven A. , Baird Debra K. , Kammermann John R. , Visco Denise M. , Goetze Leopold F. 
Published: January 2024

SUMMARY
The pattern of vertical ground reaction force redistribution among limbs during episodes of acute synovitis of the stifle in 12 mixed-breed dogs was investigated as an adjunct to a blinded nonsteroidal anti-inflammatory drug efficacy study. Without regard to drug efficacy groupings, the redistribution of vertical forces before and during the acute synovitis episode was evaluated by analysis of gait, using a force platform.
Acute synovitis was induced by intrasynovial injection of sodium urate crystals. Simultaneously, each dog was given 1 of 4 treatment regimens, including iv injection of sterile saline solution (as a negative control), phenylbutazone (as a positive control), or 1 of 2 proprietary nonsteroidal anti-inflammatory drugs. Postinjection analyses took place at 2, 4, 8, 12, 24, and 36 hours. The peak vertical force redistribution in the 3 untreated limbs of the dogs was described.
The greatest redistribution was observed 4 hours after substance injection when the synovitis was clinically at maximum. Thereafter, there was steady improvement and the dogs had a clinically normal gait 24 hours after substance injection. During synovitis, peak vertical force increased in the contralateral hind limb. During the more severe synovitis episodes, force was decreased in both forelimbs. There was good correlation between severity of lameness and peak vertical force response in the contralateral hind limb. Results of the study indicate that the untreated limbs of the same animal should not be used as a control during acute lameness studies.
Evaluation of the caudoventral portion of the mandible as a donor site for corticocancellous bone for periodontal surgery in dogs
Authors: Smith Mark M. , Saunders Geoffrey K. , Moon Martha L. , Payne John T. 
Published: January 2024

SUMMARY
Corticocancellous bone graft was obtained from the caudoventral portion of the mandible of 8 dogs. The recipient site was an alveolar jugal and alveolar defect from vital root amputation of the mesiobuccal root of the maxillary fourth premolar. Anatomic observations of 20 canine cadavers indicated that guidelines for harvesting bone from the caudoventral portion of the mandible of dogs were the mesial aspect of the masseteric fossa, the distal aspect of the roots of the first mandibular molar, and the ventral aspect of the mandibular canal. The mean weight of corticocancellous bone harvested was 0.4 ± 0.1 g. Harvested corticocancellous bone was adequate to fill recipient sites measuring a mean volume of 105.0 ± 28.5 mm3. Histologic evaluation of the recipient site revealed progressive osseous integration of the bone-graft site during a mean follow-up period of 3.5 ± 1.9 months. There was normal bone healing of the donor site without adverse effects on the mandibular molars or neurovascular structures of the mandibular canal. Vital amputation sites receiving silver amalgam had evidence of plasmacytic/lymphocytic inflammation associated with residual silver amalgam in the bone-graft area. The caudoventral portion of the mandible may be used as a donor site for autogenous corticocancellous bone in periodontal surgery of dogs.
Accuracy of a reflectance pulse oximeter in anesthetized horses
Authors: Watney G. C. G. , Norman Wendy M. , Schumacher J. P. , Beck E. 
Published: January 2024

Summary
The accuracy of a reflectance pulse oximeter was determined in 22 anesthetized horses. Oximetric blood oxygen saturation was measured with the pulse oximeter probe attached to the mucosa of the mandible. Arterial blood oxygen saturation (Sao2) was calculated from arterial blood gas values and the equine blood oxygen dissociation curve. The mean ± SD difference between oximetric blood oxygen saturation and Sao2 was −1.3 ± 3.1% for values of Sao2 ranging from 80 to 100%. The difference between oximetric blood oxygen saturation and Sao2 was influenced by Sao2, the mean arterial blood pressure, and preanesthetic medication administered, but not by age, sex, or body weight of the horse, individual animal effect, anesthetic induction or maintenance agent, procedure performed, body position, mode of lung ventilation, time of sampling, arterial pH, or carbon dioxide tension.
Effects of dietary electrolyte balance on subluxation of the femoral head in growing dogs
Authors: Kealy R. D. , Lawler D. F. , Monti K. L. , Biery D. , Helms R. W. , Lust G. , Olsson S.-E. , Smith G. K. 
Published: January 2024

Summary
Effects of increased dietary chloride and reduced sodium and potassium ion concentrations on coxofemoral joint conformation, as assessed by radiography, were examined in growing dogs. Dietary electrolyte balance was quantified by dietary anion gap (dag), defined as Na+ + K+ - Cl- in milliequivalents per 100 g of food. Diets had anion gap ranging from 8 to 41 mEq/100 g of food. One hundred sixty-seven pups from 27 litters representing 5 breeds were studied during the period of rapid growth. The extent of subluxation of the femoral head was measured on radiographs, using the method of Norberg. On average, less subluxation of the femoral head (P < 0.05) was observed when diets with lower dag were fed. Differences in dag balance did not result in different rates of weight gain; therefore, the reduction in coxofemoral joint subluxation attributable to low dag was unrelated to weight gain. Norberg angles measured at 30 weeks of age were highly correlated with coxofemoral joint status at 2 years of age, as measured by the Swedish diagnostic system and the scoring system of the Orthopedic Foundation for Animals (|r| ≥ 0.70, P < 0.0002, n = 24). This diet-related improvement in coxofemoral joint subluxation would be expected, on average, to delay or mitigate the characteristic clinical and radiographic signs of hip dysplasia in growing dogs.
Pharmacokinetics and concentrations of ceftiofur sodium in body fluids and endometrium after repeated intramuscular injections in mares
Authors: Cervantes Carlos C. , Brown Murray P. , Gronwall Ronald , Merritt Kelly 
Published: January 2024

Summary
Each of 5 healthy mares was given 5 consecutive im injections of ceftiofur sodium (2 mg/kg of body weight; 50 mg/ml) at 12-hour intervals. Ceftiofur concentrations were measured serially in serum, synovial fluid, peritoneal fluid, and urine, and were measured in CSF and endometrial tissue after the fifth dose. Mean elimination rate constant was 0.354 ± 0.101 h−1 and elimination half-life was 2.49 ± 0.49 hour. Mean serum ceftiofur concentrations peaked approximately 1 hour after each injection. The highest mean ceftiofur concentration was 5.09 μg/ml at 1 hour after the fifth dose for serum, 3.02 μg/ml at 2 hours after the fifth dose for synovial fluid, and 3.23 μg/ml at 4 hours after the fifth dose for peritoneal fluid. Mean urine concentrations reached 15.72 μg/ml at 1 hour after the fifth dose. Ceftiofur was not detected in csf or endometrial tissue. None of the mares had adverse reactions to the drug.
Dexamethasone pharmacokinetics in clinically normal dogs during low- and high-dose dexamethasone suppression testing
Authors: Greco Deborah S. , Brown Scott Anthony , Gauze Johna J. , Weise Dale W. , Buck Joan M. 
Published: January 2024

Summary
Dexamethasone pharmacokinetics was studied in 10 healthy dogs receiving high-dose administration of dexamethasone (dosage, 0.1 mg/kg of body weight, iv), alone or combined with acth (dosage, 0.5 U/kg, iv), or low-dose administration of dexamethasone (dosage, 0.01 mg/kg, iv) in an incomplete cross-over design. Serum samples were obtained at 0, 5, 10, 15, 20, 30, 45, 60, 90, 120, 180, 240, 360, 480, 720, 1,080, 1,440, 1,920, 2,400, and 2,880 minutes after dexamethasone administration; dexamethasone was measured by radioimmunoassay validated for use in dogs. Dexamethasone pharmacokinetics was adequately described by a two-compartment first-order open model.
Comparison of pharmacokinetics for the low- and high-dose protocols revealed dose dependence; area under the curve, mean residence time, clearance, and volume of distribution increased significantly when dexamethasone dosage increased. The elimination rate constant was significantly (P < 0.05) less, and the elimination half-life significantly greater for the high-dose protocols; however, the distribution rate constant and distribution half-life were not significantly different when high-dose protocols were compared with the low-dose protocol. Dose-dependent increases in volume of distribution and clearance may be related to saturation of protein-binding sites. Concurrent administration of acth did not affect dexamethasone disposition.
Histomorphologic features of the nasal cavity of pigs exposed to Pasteurella multocida type-D dermonecrotic toxin
Authors: Ghoshal Nani G. , Niyo Yosiya 
Published: January 2024

Summary
Microscopic examination of the nasal mucosa of clinically normal specific-pathogen-free pigs and of toxicogenic type-D Pasteurella multocida toxin challenge-exposed_ specific-pathogen-free pigs indicated that the surface epithelium in pigs of both groups was microscopically normal; erosions or appreciable inflammatory changes were not evident. In pigs of both groups and in all 3 regions of the nasal cavity, the endothelial lining of all blood vessels appeared normal without detectable changes to the walls at postinoculation day 10. Vascular injury in the cartilage or the bone was not discernible in control or challenge-exposed pigs.
There were marked differences in the osseous structures of the conchae when the 2 groups were compared. In control pigs, active bone formation and remodeling were observed, and the septal cartilage was normal. In toxin challenge-exposed pigs, there likewise was normal bone formation and remodeling in the vestibular region, and the septal cartilage was normal. In marked contrast, conspicuous changes were observed in the osseous core of the conchae of the respiratory and, sometimes, the olfactory regions. These changes consisted of bone necrosis and resorption by large numbers of osteoclasts with variable replacement by dense mesenchymal stroma, which resulted in conchal atrophy. In the absence of any discernible damage or injury (angiopathy) to the nasal vessels, it appears that the action of the dermonecrotoxin of P multocida serotype D is on the most active osteoblasts and the associated organic matrix of the bone, with subsequent disruption of normal bone formation and remodeling of the nasal conchae.
Ultrastructural features and pathogenesis of knobbed spermatozoa in a boar
Authors: Toyama Yoshiro , Itoh Yoneto 
Published: January 2024

Summary
Ultrastructures of knobbed spermatozoa in a boar were observed. The knobs, found at the apex of the spermatozoa, were spherical swellings of the acrosome; vacuoles were found in the swellings. According to the contents, 2 types of the vacuoles were recognized: a vacuole containing cell debris that was surrounded by 2 or 3 layers of membranes, and a vacuole containing an amorphous material that was surrounded by a single membrane. Several vacuoles might be observed in a knob. Observations of both testes indicated that the cell debris in the vacuole of the knob was derived from the cytoplasm of the Sertoli cell, which evaginated into the spermatid. Origin of the amorphous material in the other type of knob is not known.
Use of flow-volume loops to evaluate upper airway obstruction in exercising Standardbreds
Authors: Lumsden Jonathan M. , Derksen Frederik J. , Stick John A. , Robinson N. Edward 
Published: January 2024

Summary
Flow-volume loops generated from 6 Standardbreds at rest and during treadmill exercise were evaluated for their use in detecting upper airway obstruction. Tidal breathing flow-volume loops (tbfvl) were obtained from horses at rest and exercising at speeds corresponding to 75% of maximal heart rate and at maximal heart rate. The tbfvl were evaluated, using a pulmonary function computer; calculated indices describing airflow rate and expiratory-to-inspiratory airflow ratio for individual loops were determined. In addition to tbfvl indices, standard variables of upper airway function also were measured: peak airflow, peak pressure, and calculated inspiratory and expiratory impedances. Measurements were recorded before left recurrent laryngeal neurectomy (lrln; baseline) and 14 days after surgically induced left laryngeal hemiplegia.
When horses were at rest, tbfvl shape and indices describing the loop were highly variable. In contrast, in exercising horses, tbfvl shape was consistent and coefficients of variation of loop indices were less during exercise than at rest. After lrln, tbfvl from exercising horses indicated marked inspiratory airflow limitation, while the expiratory airflow curve was preserved. Peak inspiratory flow rate and inspiratory flow at 50 and 25% of tidal volume decreased, and the ratio of peak expiratory to inspiratory airflow and that of midtidal volume expiratory and inspiratory airflow rates increased significantly (P < 0.05). Inspiratory impedance also increased after lrln.
Although in resting horses tbfvl were not a useful indicator of upper airway obstruction, examination of tbfvl from exercising horses allowed objective, specific, and repeatable detection of upper airway obstruction. The technique was noninvasive, rapid, and well tolerated by horses; thus, it is a potentially valuable clinical diagnostic test.
Furosemide attenuates the exercise-induced increase in pulmonary artery wedge pressure in horses
Authors: Manobar Murli 
Published: January 2024

Summary
Right atrial (ra), right ventricular (rv), pulmonary artery (pa), and pulmonary artery wedge (paw) pressures were examined, using catheter-mounted micromanometers, in 8 healthy horses at rest and during galloping on a treadmill at belt speeds of 8, 10, and 13 m/s. The in vivo signals from the micromanometers were matched with those from conventional fluid-filled catheter transducers leveled at the scapulohumeral joint. Thirty minutes after completing control exercise measurements, furosemide was administered iv at a dosage of 1 mg/kg of body weight, and resting, as well as exercise, measurements were repeated 4 hours later. Studies also were performed on a separate day, when only postfurosemide resting and exercise data were collected. Prefurosemide and postfurosemide heart rate values for rest (37 ± 2 beats/min, mean ± sem), as well as for exercise (213 ± 5 beats/min at 13 m/s), were similar. Prefurosemide mean ra, pa, and paw pressures were increased significantly (P < 0.05) from resting values of 8 ± 2, 31 ± 2, and 18 ± 2 mm of Hg, respectively, to 44 ± 4,89 ± 5, and 56 ± 4mm of Hg with exercise at 13 m/s. Furosemide administration resulted in marked diuresis, and resting mean ra, pa, and paw pressures decreased significantly (P < 0.05) to 1 ± 1, 27 ± 2, and 11 ± 2 mm of Hg, respectively, 4 hours after furosemide administration. Although pressures increased markedly with exercise (corresponding values being 31 ± 5, 79 ± 6, and 44 ± 4 mm of Hg), these 4-hour postfurosemide exercise values were significantly (P < 0.05) less than those recorded with prefurosemide exertion. Intravascular pulmonary capillary pressure, calculated as the average of mean pa and paw pressures, during prefurosemide exercise (73 ± 5 mm of Hg) significantly (P < 0.05) exceeded that during exercise performed 4 hours after furosemide administration (61 ± 5mm of Hg). Attenuation by furosemide of the exercise-induced increase in pulmonary capillary pressure may have a role in limiting or reducing the extent of exercise-induced pulmonary hemorrhage in horses.
Serum immunoglobulin concentrations after feeding maternal colostrum or maternal colostrum plus colostral supplement to dairy calves
Authors: Francisco S. F. Abel , Quigley J. D. 
Published: January 2024

Summary
Maternal colostrum or maternal colostrum plus colostral supplement, composed of a blend of lyophilized colostrum and dried whey, was fed to 32 Holstein calves as soon as possible after birth (mean ± sem = 2.0 ± 0.2 hours) and, again, 12 hours later. Mean immunoglobulin concentration in colostrum was 59.2 mg/ml; mean immunoglobulin fraction in supplement was 11.4%. Serum immunoglobulin concentrations were measured at 0, 12, 24, 48, and 72 hours, and at 28 and 56 days. Hour/treatment interactions were significant for total immunoglobulin, IgG1, and IgM concentrations. Immunoglobulin concentrations were highest at 12 hours (total immunoglobulin, IgG1, IgM) or 24 hours (IgG2) in calves fed colostrum plus supplement, whereas all immunoglobulin concentrations were highest at 24 hours in calves fed maternal colostrum only. Peak mean immunoglobulin concentrations did not differ between treatments. Supplementation of colostrum did not increase peak mean serum immunoglobulin concentration, but did alter the serum concentration-time profile from 12 to 72 hours after birth.