bluuebunny/crossref_metadata_2025_split huggingface dataset:
Malabsorption of vitamin A in preruminating calves infected with Cryptosporidium parvum
Authors: Holland Robert E. , Boyle Stephen M. , Herdt Thomas H. , Grimes Sheila D. , Walker Robert D. 
Published: January 2024

SUMMARY
Serum retinol, retinyl palmitate, and total vitamin A concentrations, and jejunoileal morphology were examined in neonatal calves infected with Cryptosporidium parvum. Group-1 calves served as noninfected controls and, after an adjustment period, were given 50 ml of saline solution iv every 12 hours for 6 days. Group-2 calves were inoculated with 107 C parvum oocysts and, after the onset of diarrhea, were given 50 ml of saline solution iv every 12 hours for 6 days. Group-3 calves were inoculated with 107 C parvum oocysts and, after the onset of diarrhea, were treated with difluoromethylornithine (dfmo, 200 mg/kg of body weight iv, q 12 h) for 6 days. Group-4 calves were naturally infected with C parvum. Jejunoileal biopsy specimens were excised from calves of groups 1-3 at 3 and again at 15 to 16 days of age. During the course of diarrhea and 3 days after saline or dfmo administration, water-miscible retinyl palmitate was administered orally (2,750 μg/kg) to each calf in each group. Cryptosporidium parvum infection was associated with significant (P ≤ 0.05) reduction in postadministration serum retinol, retinyl palmitate, and total vitamin A concentrations in calves of groups 2, 3, and 4. Cryptosporidium parvum infection caused significant (P ≤ 0.05) reduction in villus height. Decreased villus height, villus blunting and fusion, and attenuation of the intestinal mucosa were associated with reduced absorption of vitamin A, as indicated by lower peak postadministration retinyl palmitate concentration in C parvum-infected calves. Intravenous administration of dfmo to group-3 calves did not improve retinol absorption. Vitamin A should be provided parenterally to young calves with enteric cryptosporidiosis in an attempt to avoid depletion of concurrent low liver vitamin A reserves.
Effects of monensin on selenium status and related factors in genetically hypo- and hyperselenemic growing swine
Authors: Horvath Christopher J. , Stowe Howard D. , Miller Elwin R. 
Published: January 2024

Summary
Monensin is an ionophoretic antibiotic, which selectively transports alkali metal cations across biological membranes. In growing swine, monensin toxicosis causes acute, degenerative cardiac and skeletal myopathy resembling vitamin E-selenium deficiency. Selenium is an essential trace element incorporated in glutathione peroxidase (gsh-Px), an antioxidant enzyme system that protects subcellular membranes. In our study, we examined the effects of monensin on body weight, Se balance, antioxidant status, and serum concentrations of selected minerals in growing pigs that were genetically hypo- or hyperselenemic (hypo-Se and hyper-Se, respectively). Three groups of eight 8-week-old pigs, each comprised of 4 hypo-Se and 4 hyper-Se pigs (76.4 ± 3.0 and 106.3 ± 10.3 ng of Se/ml of serum, respectively), were fed standard diets containing 0.1 mg of supplemental Se/kg of body weight, and either 0, 200, or 400 mg of monensin/kg for a 77-day period, followed by a 28-day monensin withdrawal period. On days 0, 7, 28, 56, 70, and 98, all pigs were weighed and blood was collected for determination of serum gsh-Px, creatine phosphokinase, and aspartate transaminase values, as well as serum concentrations of vitamin E, Se, Ca, Cu, Fe, K, Mg, Na, P, and Zn. Significance of main effects of monensin treatment, genetic Se status, and their interactions was tested by Fisher's variance ratio test, followed by conditional comparison of treatment means with a Bonferroni test. Signs of monensin toxicosis were not observed and monensin consumption had no effect on body weight, or serum creatine phosphokinase, aspartate transaminase, or Se values. However, pigs consuming monensin had consistently higher serum gsh-Px activities, possibly because of increased synthesis of this adaptive antioxidant enzyme. Interactions were not found between monensin and genetic Se status. Hyperselenemic pigs were heavier and had higher serum Se and gsh-Px values than hypo-Se pigs. Furthermore, hypo-Se and hyper-Se pigs were hypo- and hypercupremic, respectively, suggesting genetic regulation of copper status. It is likely that pigs with inadequate antioxidant status (hyposelenemia, hypocupremia) are more susceptible to diseases associated with cellular membrane damage, such as vitamin E-Se deficiency disease and monensin toxicosis.
Neuromuscular and cardiovascular effects of atracurium in isoflurane-anesthetized chickens
Authors: Nicholson Anthony , Ilkiw Jan E. 
Published: January 2024

Summary
Atracurium besylate, a nondepolarizing neuromuscular blocking agent, was administered to 24 isoflurane-anesthetized domestic chickens. Birds were randomly assigned to 4 groups, and atracurium was administered at dosage of 0.15, 0.25, 0.35 or 0.45 mg/kg of body weight. The time of onset of twitch depression, the amount of maximal twitch depression, and the duration of muscular relaxation were recorded. After return to control twitch height, atracurium was further administered to achieve > 75% twitch depression. When twitch depression reached 75% during noninduced recovery, 0 5 mg of edrophonium/kg was administered to reverse the muscle relaxation. Throughout the experimental period, cardiovascular, arterial blood gas, and acid-base variables were monitored.
The effective dosage of atracurium to result in 95% twitch depression in 50% of birds, (ed95/50) was calculated, using probit analysis, to be 0.25 mg/kg, whereas the ed95/95, the dosage of atracurium to result in 95% twitch depression in 95% of birds, was calculated by probit analysis to be 0.46 mg/kg. The total duration of action at dosage of 0.25 mg/kg was 34.5 ± 5.8 minutes; at the highest dosage (0 45 mg/kg), total duration increased 0 47.8 ± 10.3 minutes. The return to control twitch height was greatly hastened by administration of edrophonium. Small, but statistically significant changes in heart rate and systolic blood pressure, were associated with administration of atracurium and edrophonium. These changes would not be clinically relevant.
In this study, atracurium was found to be safe and reliable for induction of muscle relaxation in isoflurane-anesthetized chickens.
Cerebrospinal fluid changes after iopamidol and metrizamide myelography in clinically normal dogs
Authors: Widmer William R. , DeNicola Dennis B. , Blevins William E. , Cook James R. , Cantwell H. Dan , Teclaw Robert F. 
Published: January 2024

Summary
Cerebrospinal fluid samples from 2 groups of clinically normal dogs were compared after iopamidol (n = 9) and metrizamide (n = 8) myelography. Iopamidol (200 mg of I/ml) and metrizamide (170 mg of I/ml) were administered by cerebellomedullary injection at dosage of 0.45 ml/kg of body weight. In dogs of both groups, postmyelographic csf changes included high specific gravity, Pandy score, protein concentration, and wbc count. The high specific gravity and Pandy score were false-positive effects attributed to nonionic contrast media. Although postmyelographic protein concentration and total wbc count were greater in csf samples from dogs given metrizamide than in those given iopamidol, differences were not statistically significant. The differential wbc counts were consistent with mild, acute leptomeningitis; these findings were supported by results of histologic examination. Iopamidol and metrizamide should be considered low-grade leptomeningeal irritants in dogs.
Evaluation of the Doppler ultrasonic method of measuring systolic arterial blood pressure in cats
Authors: Grandy J. L. , Dunlop C. I. , Hodgson D. S. , Curtis C. R. , Chapman P. L. 
Published: January 2024

Summary
The accuracy of the Doppler technique for indirect systolic blood pressure measurement was assessed in 16 anesthetized cats. Eight cats were anesthetized with isoflurane and 8 were anesthetized with halothane. Anesthetic depth and mode of ventilation were varied to obtain a wide range of arterial blood pressure. A Doppler transducer was placed on the palmer surface of the left forelimb over the common digital branch of the radial artery to detect blood flow, and a blood pressure monitoring cuff with a width 37% the limb circumference was placed half way between the elbow and the carpus. To enable direct arterial pressure measurements, the left femoral artery was catheterized and the blood pressure waveforms recorded simultaneously.
Systolic blood pressure measured by use of the Doppler ultrasonic technique was significantly lower than that obtained from the femoral artery catheter. Using linear regression, we determined a clinically useful calibration adjustment for Doppler indirect blood pressure measurement in cats: femoral systolic pressure = Doppler systolic pressure + 14 mm of Hg.
High-resolution computed tomography of the mammalian lung
Authors: Chen Qihang , Klein Jeffrey S. , Gamsu Gordon , Webb W. Richard 
Published: January 2024

Summary
High-resolution computed tomography (HRCT) was performed in 21 isolated animal lungs, from 4 mammalian species (pigs, rabbits, dogs, sheep). Gross and subgross central and peripheral lung morphology was determined by HRCT. Three distinct types of lungs can be identified, principally based on the extent of interlobular septal development; the relationship of major vessels to airways; and the thickness of the visceral pleura. Type-I lung is found in pigs, sheep, and cattle; type-II lung is found in rabbits, dogs, cats, and monkeys; and type-IH lung is found in human beings and horses.1 These mammalian lungs were compared with human lungs. The potential use of HRCT to investigate specific human lung diseases in the aforementioned species also was considered.
Characteristics of L-glutamine transport in equine jejunal brush border membrane vesicles
Authors: Salloum Rabih M. , Duckworth Donna , Madison John B. , Souba Wiley W. 
Published: January 2024

SUMMARY
The sodium-dependent transporter system responsible for L-glutamine uptake by brush border membrane vesicles prepared from equine jejunum was characterized. Vesicle purity was ascertained by a 14- to 17-fold increase in activity of the brush border enzyme markers. Glutamine uptake was found to occur into an osmotically active space with negligible membrane binding. The sodium-dependent velocity represented approximately 80% of total uptake and demonstrated overshoots. Kinetic studies of sodium-dependent glutamine transport at concentrations between 5 μM and 5 mM revealed a single saturable high-affinity carrier with a Michaelis constant of 519 ± 90 μM/ and a maximal transport velocity of 3.08 ± 0.97 nmol/mg of protein/10 s. Glutamine uptake was not affected by changes in environmental pH. Lithium could not substitute for sodium as a contransporter ion. 2-Methylaminoisobutyric acid inhibited the sodium-dependent carrier only minimally, but marked inhibition (> 90%) was observed in the presence of histidine, alanine, cysteine, and nonradioactive glutamine. Kinetic analysis of the sodium-independent transporter revealed it to have a Michaelis constant = 260 ± 47 μM and a maximal transport velocity of 0.32 ± 0.06 nmol/mg of protein/10 s. We conclude that glutamine transport in equine jejunal brush border membrane vesicles occurs primarily via the system B transporter and, to a lesser extent, by a sodium-independent carrier.
Fetal heart rate patterns and the influence of myometrial activity during the last month of gestation in cows
Authors: Jonker F. H. , van Oord H. A. , van der Weyden G. C. , Taverne M. A. M. 
Published: January 2024

SUMMARY
Five cows in the last month of gestation, provided with uterine electrodes and in which catheters had been chronically installed in the fetal aorta, were used to study patterns of fetal heart rate (fhr) and the influence of periods of myometrial electrical activity during gestation (contractures) on fhr. The fhr was calculated by counting the number of blood pressure pulses on the tracings during alternate periods of 12 seconds. Three 1-hour recordings without contractures and 10 recordings during the time of a contracture were randomly selected for each cow. The calculated data points were plotted on a graph to display fhr patterns.
In 41 periods associated with single contractures, fhr data points were taken every 72 seconds. Changes in absolute and relative fhr in these periods were determined to analyze a possible effect of contractures on fhr.
Three types of variation in fhr patterns could be distinguished: a short-term, low-amplitude variation of basal FHR; a second type in which the duration was < 4 minutes and the amplitude was ≥ 15 beats/ min; and prolonged periods with increased or decreased fhr values (> 4 minutes and ≥ 15 beats/ min). The relationship between these types of variation and fetal activity states remains to be established for cows. During the 60 hours of recordings that were analyzed, a period of several minutes during which fhr values were extremely high (> 180 beats/min) was found 3 times. There were no significant differences in absolute or relative fhr before, during, or after a contracture.
Elbow arthroscopy in clinically normal dogs
Authors: Van Ryssen Bernadette , van Bree Henri , Simoens Paul 
Published: January 2024

SUMMARY
After a detailed anatomic study to determine puncture sites, 10 cadaver elbows from 5 dogs were examined arthroscopically to study the normal intraarticular anatomy, as viewed from the medial side. Subsequent dissection revealed absence of neurovascular injury and only minor iatrogenic damage to the cartilage. The technique was clinically applied and evaluated in 13 dogs (26 joints). The dogs recovered without complications. The technique proved to be safe and reliable for direct examination of nearly the entire joint. More specifically, it allowed systematic inspection of the medial and lateral humeral condyles, the medial and lateral coronoid processes, the caudal and middle parts of the head of the radius, the olecranon (including the anconeal process), and the medial collateral ligament.
Intraosseous pressure and pathologic changes in horses with navicular disease
Authors: Pleasant R Scott , Baker Gordon J. , Foreman Jonathan H. , Eurell Jo Ann C. , Losonsky John M. 
Published: January 2024

SUMMARY
Navicular bone intraosseous pressure, gross pathologic, histologic, and histochemical data were collected from 8 horses with navicular disease and 4 control horses. Simultaneous navicular bone intraosseous, medial palmar arterial, and saphenous venous pressures were measured for the left and right forelimbs of each horse under general anesthesia. Gross pathologic evaluation included grading of changes on the flexor surface of the navicular bone. Safranin-O-fast green-stained sections were used for histologic-histochemical grading of the hyaline articular and fibrocartilage surfaces of the navicular bones. Hematoxyhn and eosin-stained sections were used for morphologic evaluation of the marrow spaces of navicular bones. Mean navicular bone intraosseous pressure for horses with navicular disease was significantly (P< 0.001) higher than that for controls. Differences in medical palmar arterial or saphenous venous pressures were not significant between groups. The median flexor surface gross pathologic and histologic-histochemical fibrocartilage scores for horses with navicular disease were significantly (P< 0.001) more severe than those for control horses. The histologic-histochemical hyaline cartilage scores for control horses and those for horses with navicular disease were not significantly different. Fibrosis of the marrow spaces beneath the flexor cortex of horses with navicular disease was more pronounced than that of control horses.
Detection of bluetongue virus from blood of infected sheep by use of an antigen-capture enzyme-linked immunosorbent assay after amplification of the virus in cell culture
Authors: Mecham James O. 
Published: January 2024

SUMMARY
An antigen-capture elisa was used to detect bluetongue virus (btv) from blood of infected sheep. A rabbit-origin capture antibody and a mouse-origin detection antibody combined with biotin-avidin amplification were used for the assay. The antigen-capture elisa could not detect virus directly from the blood of infected sheep because of low virus titer. To enhance detection, virus from infected blood was amplified in cell culture. Virus could then be detected from cell culture supernatant fluids, using the elisa. This amplification step increased the sensitivity of the assay comparable to that of assays performed in cell culture measuring cytopathic effects. The elisa procedure was specific for btv and did not mistakenly identify the antigenically related epizootic hemorrhagic disease virus. The antigen-capture elisa permitted indirect quantitation and identification of btv from the blood of infected sheep.
Effect of Corynebacterium pseudotuberculosis phospholipase D on viability and chemotactic responses of ovine neutrophils
Authors: Yozwiak Michael L. , Songer J. Glenn 
Published: January 2024

SUMMARY
Corynebacterium pseudotuberculosis phospholipase D (PLD) significantly affected viability of ovine neutrophils after 24 hours' exposure. This effect was more marked in cells that ingested PLD emulsified in oil. Treatment of neutrophils with PLD significantly (P < 0.05) reduced the ability of these cells to migrate toward activated sheep serum. The PLD was not chemotactic, but it activated normal sheep serum, producing factors that were chemotactic for neutrophils.
Transcutaneous oxygen monitoring for predicting skin viability in dogs
Authors: Rochat Mark C. , Pope Eric R. , Payne John T. , Pace Lanny W. , Wagner-Mann Colette C. 
Published: January 2024

SUMMARY
Transcutaneous oxygen (PO2-TC) monitoring is commonly used in human medicine for evaluating skin viability. The application of transcutaneous monitoring for evaluating skin viability in dogs was investigated.
The changes in PO2-TC values were measured from 16 avascular skin flaps created along the lateral hemithoraces of 4 dogs. Transcutaneous oxygen values were serially recorded from the vascular base and avascular apex of each flap for 12 hours after surgery. A single transcutaneous measurement was obtained from each flap base and apex 24 hours after surgery. Serial arterial blood gas analyses were obtained to compare central oxygen values with PO2-TC values. Full-thickness skin biopsy specimens were harvested from the base and apex of each flap 24 hours after surgery. The flaps were observed for 4 days and then excised for histologic examination. A subjective grading scale was used to assess histologic changes.
Throughout the 12-hour period and at 24 hours, a statistically significant difference was found between the PO2-TC values for apices and bases of the flaps. The mean PO2-TC for all bases was 90.9 mm of Hg ± 3.3 SEM, and the mean PO2-TC for all apices was 21.2 mm of Hg ± 1.8 SEM. The mean regional perfusion index (apex PO2-TC/base PO2-TC) was 0.23 ± 0.02. The subjective numbers assigned to the biopsy specimens were statistically evaluated by using a paired Student's t test and a Wilcoxon signed-rank test. A significant difference was found between the numbers for the collective bases and apices with both tests. A statistically significant difference was found between the numbers for the apex biopsy specimens taken 24 hours after creation of the skin flap and those taken when the flap was excised, whereas no difference was found between the numbers for the base biopsy specimens. On the basis of our findings, PO2-tc monitoring is a useful technique for assessing skin viability in dogs.
Relation between reduced glutathione content and Heinz body formation in sheep erythrocytes
Authors: Goto Ikuo , Agar N. S. , Maede Yoshimitsu 
Published: January 2024

Summary
To clarify the oxidant defense functions of reduced glutathione (gsh) in erythrocytes, the effect of gsh deficiency on in vitro oxidant defense was studied, using gsh-deficient sheep erythrocytes (low-gsh cells). The formation of Heinz bodies in low-gsh cells was higher than that in high-gsh cells when the cells were incubated with an oxidant drug, acetylphenylhydrazine (aph). Artificial depletion of gsh by 1-chloro-2,4-dinitrobenzene in high-gsh cells resulted in increased Heinz body formation in these cells incubated with aph. Furthermore, high negative correlation was observed between Heinz body formation and gsh content in sheep erythrocytes exposed to aph. These results clearly indicate that erythrocyte gsh is indispensable for erythrocyte defense against oxidative damage induced by aph, and support the previous observations that sheep with low-gsh erythrocytes were more susceptible to oxidative agents than were sheep with high-gsh erythrocytes.
Comparison of excretory urography and ultrasonography for detection of experimentally induced pyelonephritis in dogs
Authors: Neuwirth L. , Mahaffey M. , Crowell W. , Selcer B. , Barsanti J. , Cooper R. , Brown J. 
Published: January 2024

Summary
Pyelonephritis was experimentally induced in 10 clinically normal dogs by nephropyelocentesis and introduction of Proteus mirabilis into the randomly chosen right or left renal pelvis. Dogs were examined by nephrosonography and excretory urography before and 2 weeks after infection.
The major nephrosonographic findings of pyelonephritis were renal pelvic dilatation, usually with proximal ureteral dilatation, and a hyperechoic mucosal margin line within the renal pelvis, proximal portion of the ureter, or both. In addition, at least one or more of the following were observed: generalized hyperechoic renal cortex, focal hyperechoic areas within the medulla, and focal hyperechoic or hypoechoic cortical lesions.
Interpretation of excretory urograms resulted in 3 false-negative and 1 false-positive conclusions, compared with the histologic findings. Interpretation of nephrosonograms resulted in 2 false-negative and no false-positive conclusions. Of the kidneys with histologic evidence of pyelonephritis, 73% were detected by excretory urography, whereas 82% were detected by nephrosonography.
Nephrosonography appeared to be useful for detection of mild to moderate cases of acute pyelonephritis that may be be interpreted as such by excretory urography.
Possible involvement of protein kinase C with induction of haptoglobin in cows by treatment with dexamethasone and by starvation
Authors: Yoshino Kazuhiro , Katoh Norio , Takahashi Kiyoshi , Yuasa Akira 
Published: January 2024

Summary
Haptoglobin (Hp), an acute-phase protein, is detected in serum of cows with hepatic lipidosis (fatty liver). To assess the relevance of Hp in fatty liver, induction of Hp was examined, using conditions similar to those involving development of fatty liver in cows. Induction of Hp was achieved by a combination of dexamethasone administration (0.1 mg/kg of body weight) and 2 days’ starvation. Haptoglobin appearance in serum was not associated with the increase of α1-acid glycoprotein (a marker for inflammation). This treatment increased serum nonesterified fatty acids concentration and decreased serum triglycerides concentration. Protein kinase C activity was decreased in the cytosolic fractions of liver and mononuclear cells. Reduction of protein kinase C-catalyzed endogenous protein phosphorylation also was observed, particularly in the cytosolic fractions of the tissue and cells. Detection of Hp in serum of cows with fatty liver appears to be explained by the fact that Hp is induced by dexamethasone administration and starvation, which are similar to the condition responsible for fatty liver development. The change of protein kinase C-catalyzed phosphorylation was suggested to be involved in the induction of Hp in cows.