bluuebunny/crossref_metadata_2025_split huggingface dataset:
Myoelectric activity of the small intestine in enterotoxin-induced diarrhea of calves
Authors: Roussel A. J. , Woode G. N. , Waldron R. C. , Sriranganathan N. , Jones M. K. 
Published: January 2024

Summary
Electrodes were surgically implanted at 15-cm intervals in the jejunum and ileum of 4 healthy neonatal calves so that myoelectric activity could be recorded on 2 consecutive days. On the first day, each calf received a control treatment, and myoelectric activity was recorded for 340 minutes. Phase I was recorded for a mean of 175.8 ± 22.8 minutes (51.5%), phase II for 124 ± 27.4 minutes (36.5%), and phase III for 40.3 ± 6 minutes (11.9%). On the second day, each calf was treated with approximately 200 μg of heat-stable enterotoxin (STa) of Escherichia coli orally. All calves developed diarrhea after the administration of STa. Phase I was recorded for a mean of 92.5 ± 42.3 minutes (27.2%), phase II for 227.3 ± 52.5 minutes (66.9%), and phase III for 20.3 ± 11.4 minutes (6.0%). Increase in phase II and decrease in phases I and III after STa administration were significant (P < 0.05). Duration of the migrating myoelectric complex was longer after STa administration (median, 64 minutes), compared with the control treatment (median, 54 minutes). Minute rhythms, recorded on the day of toxin administration, ranged from 49 to 153 minutes. There was no difference between the number of migrating action potential complexes on the control days (range, 1 to 10), compared with those on treatment days (range, 1 to 14).
These findings are suggestive that enterotoxin-induced diarrhea of calves is accompanied by increased total spiking activity and minute rhythms in the distal portion of the jejunum and ileum.
Effects of fluoride on secretory and postsecretory phases of enamel formation in sheep molars
Authors: Milhaud Guy E. , Charles Eliane , Loubiàre Marie-Laure , Kolf-Clauw Martine , Joubert Christophe 
Published: January 2024

Summary
Effect of fluoride was assessed on molars during and after mineralization. Two groups of 7 sheep each were dosed orally with 3.5 mg of fluoride/kg of body weight daily for 4 months (from 5 to 9 months after birth). Sheep of the first group were slaughtered immediately after fluoride administration; those of the second group were slaughtered 4 months later at the age of 13 months. Three control groups of 7 sheep each were slaughtered at 5 months (to determine the state of the teeth at the beginning of fluoride administration), and at 9 and 13 months.
During fluoride administration, plasma fluoride concentration rapidly increased to about 0.50 μg/ml; after fluoride administration, it stabilized at 0.20 μg/ml in treated sheep, whereas controls had concentration of 0.10 μg/ml (P < 0.01).
Parts of the molars that were in the process of mineralization during fluoride administration (mainly second molars) had thinning enamel, with pits, mainly close to the apex, marked decrease in hardness throughout the layer (< 100 Vickers U, compared with 240 Vickers U), and fluoride accumulation twice as high as that in controls (1,000 to 2,500 mg/kg [dry weight]). Fluoride accumulation was higher in dentine (2,700 to 4,200 mg/kg), but hardness was less affected.
On parts of the molars that were already mineralized (mostly, the first molar), changes in the appearance of enamel and cementum, decreased hardness (less important than in teeth during mineralization) affecting outer enamel more than inner enamel, high fluoride concentration (4,000 to 5,500 mg/kg [dry weight]) in outer enamel extending over 200 (μm were observed. Thus, in sheep, fluoride has a substantial postsecretory effect that may be explained by a slower maturation phase of enamel in this species.
Because molar wear is correlated to enamel hardness (dentine at the occlusal surface has low resistance—30 Vickers U), abnormal abrasion of molar teeth that have mineralized before and during fluoride intakes can be observed.
Serum and skin concentrations after multiple-dose oral administration of trimethoprim-sulfadiazine in dogs
Authors: Pohlenz-Zertuche Heidy Ortiz , Brown Murray P. , Gronwall Ronald , Kunkle Gail A. , Merritt Kelly 
Published: January 2024

Summary
Six healthy adult mixed breed dogs were each given 5 oral doses of trimethoprim (TMP)/sulfadiazine (sdz) at 2 dosage regimens: 5 mg of TMP/kg of body weight and 25 mg of SDZ/kg every 24 hours (experiment 1) and every 12 hours (experiment 2). Serum and skin concentrations of each drug were measured serially throughout each experiment and mean serum concentrations of tmp and sdz were determined for each drug for 24 hours (experiment 1) and 12 hours (experiment 2) after the last dose was given. In experiment 1, mean serum tmp concentration was 0.67 ± 0.02 μg/ml, and mean skin tmp concentration was 1.54 ± 0.40μg/g. Mean serum sdz concentration was 51.1 ± 12.2 μg/ml and mean skin sdz concentration was 59.3 ± 9.8 μg/g. In experiment 2, mean serum tmp concentration was 1.24 ± 0.35 μg/ml and mean skin tmp concentration was 3.03 ± 0.54 μg/g. Mean serum SDZ concentration was 51.6 ± 9.3 μg/ml and mean skin sdz concentration was 71.1 ± 8.2 μg/g. After the 5th oral dose in both experiments, mean concentration of tmp and sdz in serum and skin exceeded reported minimal inhibitory concentrations of tmp/sdz (≤ 0.25/4.75 μg/ml) for coaguase-positive Staphylococcus sp. It was concluded that therapeutically effective concentrations in serum and skin were achieved and maintained when using the manufacturer’s recommended dosage of 30 mg of tmp/sdz/kg (5 mg of TMP/kg and 25 mg of sdz/kg) every 24 hours.
Influence of body size on tibial nerve somatosensory evoked potentials in dogs
Authors: Poncelet Luc , Michaux Charles , Balligand Marc 
Published: January 2024

SUMMARY
Somatosensory evoked potentials in response to tibial nerve stimulation were recorded from the scalp of 31 clinically normal mixed-breed dogs. The latency and amplitude of a main positive potential (P18), recorded with a frontal electrode referenced to the nose, were measured in subjects with body length ranging from 316 to 962 mm. A linear relation to body size explained the variations in latency among dogs (r2= 0.81); the amplitude variations were explained in part by body size (r2= 0.44). Bilateral tibial nerve stimulation significantly (P<0.05) increased the amplitude of P18, but its latency was unaffected, compared with unilateral stimulation. Results of unilateral right and left tibial nerve stimulation were compared and were not different. Replacing acepromazine with xylazine as premedication before thiopental anesthesia did not influence the recordings.
Enhancement of lymphocyte function and interleukin 1β transcription by recombinant bovine interleukin 1β
Authors: Stabel Judith R. , Kehrli Marcus E. , Goff Jesse P. 
Published: January 2024

SUMMARY
Six nonpregnant, nonlactating Jersey cows, averaging 4 to 6 years old, were used to evaluate the immunomodulatory effects of recombinant bovine interleukin 1β (rBoIL-1β). Cows were given 166 ng of rBoIL-1β/kg of body weight at 8-hour intervals for 96 hours. Persistent leukocytosis was observed within 3 hours of rBoIL-1 treatment, peaking 24 hours after the first IL-1β injection and returning to baseline values within 72 hours after cessation of IL-1β treatment. Injection of cows with rBoIL-1β stimulated lymphocyte blastogenesis and mitochondrial methyl-thiazoltetrazolium cleavage activity in resting cell cultures. Increases in the aforementioned lymphocyte activities were also observed in stimulated blood mononuclear cell cultures during IL-1β administration. Change in IgM production in cell cultures was not observed during IL-1β treatment. Within 24 hours of the first IL-1β injection, IL-1β mRNA transcription in stimulated blood mononuclear cell cultures was markedly increased, suggesting that IL-1β upregulates its own production in mononuclear cells. These data provide evidence that administration of cytokines, such as rBoIL-1β, enhances immune cell function and, therefore, may be useful in alleviating immunosuppression in cattle.
Effect of 4-bromo-calcium ionophore A23187 on release of Anaplasma marginale from bovine erythrocytes in vitro
Authors: Blouin Edmour E. , Blankemeyer James T. , Kocan Katherine M. , Ewing S. A. 
Published: January 2024

SUMMARY
The ionophore A23187 was used to facilitate release and continued development of Anaplasma marginale in short-term erythrocyte cultures. Addition of 10 μM A23187 to the cultures resulted in significant decrease in percentage of parasitized erythrocytes (ppe) by 24 hours after treatment; further development and increase in PPE was not observed. In contrast, the ppe of untreated cultures, those treated with dimethyl sulfoxide (dmso) only and with 1 μM A23187 increased slightly during that time. Total erythrocyte count decreased in treated cultures in excess of that expected after samples of the medium were taken for analysis. The greatest cell loss and increased hemoglobin concentration in culture medium was observed in cultures treated with 10 μM A23187 and with an equivalent volume of dmso. The dmso appeared to cause hemolysis of some erythrocytes, but not of infected cells selectively. Release of A marginale inclusion bodies was seen by electron microscopy in samples from the 10 μM A23187-exposed cultures. At 30 minutes after treatment, free initial bodies were frequently seen. Inclusion body membranes and individual A marginale were associated with membranes of adjacent erythrocytes. Individual rickettsiae were seen in cell depressions and appeared to be entering erythrocytes. However, neither further invasion nor development of the parasite in erythrocytes was observed. Ionophore A23187 appeared to promote release of A marginale from erythrocytes, but did not enhance infection of erythrocytes or development of organisms in vitro.
Cardiovascular responses to exogenous platelet-activating factor (PAF) in anesthetized ponies, and the effects of a PAF antagonist, WEB 2086
Authors: Wilson D. V. , Eberhart S. W. , Robinson N. E. , Rice R. , Gray P. R. 
Published: January 2024

SUMMARY
The effects of exogenous platelet-activating factor (paf) were determined in anesthetized ponies. Administration of paf induced a decrease in cardiac index that resulted in systemic hypotension. This was followed by tachycardia, hypertension, and a return of cardiac index to baseline. Pulmonary aterial pressure increased markedly because of pulmonary vasoconstriction. Exogenous paf also caused leukopenia and thrombocytopenia. The specific PAP receptor antagonist (WEB 2086) blocked all paf-induced changes. Flunixin meglumine, a cyclooxygenase inhibitor, abolished the pulmonary hypertension and tachycardia, and attenuated the systemic hypotension but did not change the paf-induced peripheral cellular changes. The paf antagonist also inhibited platelet aggregation induced by paf in vitro. The paf-induced changes are similar to those reported after endotoxin exposure in horses.
Effect of a specific platelet-activating factor antagonist on cardiovascular and peripheral cellular responses to colonic ischemia and reperfusion in anesthetized ponies
Authors: Wilson D. V. , Stick J. A. 
Published: January 2024

SUMMARY
The role of platelet-activating factor in mediating the cardiovascular and peripheral cellular responses to large-colon ischemia and reperfusion, was explored in anesthetized ponies. A specific platelet-activating factor (PAF) antagonist (WEB 2086) was administered to a group of 6 ponies, and another 6 ponies (controls) were given an equivalent volume of saline solution, prior to 1 hour of large-colon torsion. After correction of the torsion, ponies were monitored during the reperfusion period. Significant (P < 0.05) hypotension and metabolic acidosis developed in all ponies after correction of colonic torsion, cardiac index increased initially, but then decreased significantly (P < 0.05) over the study period. Mean times between correction of torsion and onset of cardiac failure and death were not different between groups. Significant (P < 0.05) thrombocytopenia developed during the reperfusion period in control ponies, but not in WEB-treated ponies. Blood leukocyte concentration in control ponies was more variable and significantly (P < 0.05) decreased immediately upon reperfusion, compared with that in WEB-treated ponies. We conclude that although the cardiovascular responses to colonic ischemia and reperfusion are not prevented by use of a specific paf-antagonist, specific peripheral cellular responses are mediated by paf.
Expression of calbindin-D28k in developing and growing ovaries of chicken embryos
Authors: Inpanbutr N. , Taylor A. N. 
Published: January 2024

Summary
Immunoreactivity for 28 kd vitamin D-dependent calcium-binding protein (calbindin-D28k) has been localized in the germinal epithelium and cells surrounding oogonia and oocytes (future granulosa cells) of developing and growing ovaries of chicken embryos. The protein first appeared prominently in the germinal epithelium of the developing left ovary in 8-day embryos. At the twelfth day of incubation, cells surrounding oogonia and oocytes reacted intensely for calbindin-D28k. The number and intensity of calbindin-D28k-containing cells increased in both types of cells as the embryos further developed. Calbindin-D28k remained in the germinal epithelium throughout the study period observed (up to 10 weeks). However, the protein was present transiently in the future granulosa cells. It gradually decreased after hatching, and was virtually absent from granulosa cells in a 10-week old chicken. Compared with the known process of onset of sexual development, these results indicated possible involvement of calbindin-D28k in the early phases of oogenesis in chicken ovaries.
Correlations between histologic endometrial lesions in mares and clinical response to intrauterine exposure with Streptococcus zooepidemicus
Authors: Troedsson Mats H. T. , deMoraes Marcos J. , Liu Irwin K. M. 
Published: January 2024

Summary
The relationship between histologic lesions in endometrial biopsy specimens and susceptibility to chronic uterine infection (cui) in mares was investigated. Mares were allotted to 4 groups on the basis of degree of endometrial lesions. Mares in group 1 (n = 6) had no pathologic changes, mares in group 2 (n = 5) had only mild pathologic changes, group-3 mares (n = 7) had moderate changes, and group-4 mares (n = 7) had severe inflammatory and fibrotic endometrial changes. Susceptibility to cui was determined by the inflammatory response to intrauterine inoculation of 5 × 106 Streptococcus zooepidemicus. The inoculum was given on the third day of behavioral estrus and in the presence of a follicle > 30 mm. Mares with > 1 neutrophil/5 high-magnification (400 ×) microscopic fields and > 20 colonies of S zooepidemicus at 96 hours after inoculation were considered to be susceptible to cui.
There was a significant association between biopsy grade and susceptibility to cui among the groups. Histologically normal endometrium was associated with resistance to cui, and severe histopathologic changes in the endometrium were associated with susceptibility to cui. Mild to moderate endometrial lesions did not correlate consistently with susceptibility or resistance to cui.
Development of a DNA probe for identification of bovine herpesvirus 4
Authors: Galik P. K. , van Santen V. L. , Stringfellow D. A. , Bird R. C. , Wright J. C. , Smith P. C. 
Published: January 2024

Summary
A sensitive and specific dna probe for detection and identification of bovine herpesvirus 4 (bhv-4) was developed. Cloned fragments from a library of HindIII fragments of the bhv-4 (DN-599) genome were labeled with 32P or digoxigenin and were tested for sentitivity and specificity in detecting viral dna by dot-blot hybridization. Two probes were identified that detected 10 pg of purified viral dna, and detected viral dna in 0.001 μg of total dna extracted from bhv-4-infected cells. Both probes labeled with 32P and 1 labeled with digoxigenin detected viral dna in samples prepared from cells infected with 2 prototype strains (DN-599 and Movar 33/63) and 4 field isolates of bhv-4. The dna probes did not hybridize to total dna prepared from uninfected bovine cells or from cells infected with bhv-1, bhv-2, alcelaphine herpesvirus 1, pseudorabies virus, or equine herpesvirus 1. One probe, labeled with digoxigenin, was tested further by dot-blot hybridization with infected cell lysates that were simply treated with sodium dodecyl sulfate and proteinase K prior to application to the membrane, avoiding extensive dna purification procedures. This simplified procedure also resulted in specific detection of field isolates of bhv-4 and prototype strains of bhv-4.
Ultrastructural hepatocellular features associated with severe hepatic lipidosis in cats
Authors: Center S. A. , Guida L. , Zanelli M. J. , Dougherty E. , Cummings J. , King J. 
Published: January 2024

Summary
In this study, we compared hepatic ultrastructure in healthy cats, in cats with severe hepatic lipidosis, and in cats with experimentally induced, chronic, extrahepatic bile duct occlusion. Ultrastructural features unique to the lipidosis syndrome included an apparent reduction in number of peroxisomes and alteration in their morphologic features. The quantity of endoplasmic reticulum, Golgi complexes, and lysosomes was subjectively reduced, and paucity of cytosolic glycogen was observed. Bile canaliculi appeared collapsed because of cytosolic distention with lipid. Mitochondria were reduced in number and were markedly pleomorphic. Cristae assumed a variety of shapes, lengths, and orientations. Ultrastructural features of bile duct occlusion were similar to those described in other species and differed from those in cats with hepatic lipidosis.
Isolation of an inhibitor of tumor necrosis factor-α-mediated cytotoxicity liberated from chemotaxin-stimulated equine white blood cell populations
Authors: Coyne C. P. , Fenwick Brad W. , Iandola John , Williams David , Griffith Gary 
Published: January 2024

Summary
Objectives of this investigation were to extract and isolate protein fractions inhibitory to the cytotoxic properties of tumor necrosis factor-α (tnf-α). In this context, mixed populations of wbc were harvested from equine blood and were stimulated with a combination of a synthetic chemotactic peptide and a calcium ionophore. Several methods were subsequently applied for the initial preparation of cell-free crude protein extracts, including fractional precipitation with gradient concentrations of ammonium sulfate and preparative-scale isoelectric focusing. In addition, protein fractions were harvested from extracts of concentrated equine urine. Protein extracts of urinary origin were further separated by gel-filtration column chromatography.
Identification of protein fractions possessing properties inhibitory to the cytotoxic characteristics of tnf-α was facilitated by a tissue culture-based technique for the biological assay of tnf-α-mediated cytotoxicity. Purified protein extracts possessed a marked ability to inhibit or neutralize the cytotoxic properties of tnf-α, on the basis of survival of murine fibrosarcoma cell populations, compared with appropriate negative and positive reference controls. Relative purity of inhibitors and estimation of approximate molecular weight were established by conventional reducing and nonreducing sodium dodecyl sulfate polyacrylamide gel electrophoresis analysis. Equine inhibitory protein fractions from mixed wbc populations, purified in the manner described, had molecular weights of 70,000 to 80,000 and 28,000. An analogous protein fraction of 28 kDa also was isolated from equine concentrated urine. Estimated isoelectric point of tnf-α inhibitor protein fractions was between pH of 5.5 and 6.1. These physical characteristics of equine tnf-α inhibitor protein fractions were similar to those described for a membrane-associated tnf-α receptor protein shed from chemotaxin- and calcium-ionophor-stimulated human wbc populations.
Immunologic changes in Ostertagia ostertagi-infected calves treated strategically with an anthelmintic
Authors: Yang C. , Gibbs H. C. , Xiao L. 
Published: January 2024

Summary
Immunomodulation by Ostertagia ostertagi and the effects of strategic anthelmintic treatments were studied in 3 groups of 6 calves each: an infected group, inoculated with 100,000 third-stage larvae (L3)/calf at 1 and 28 days; an infected-treated group, similarly inoculated, but treated with ivermectin 9 days after each inoculation; and a noninfected control group. Calves were grazed on 2 previously clean pastures, with the infected and infected-treated calves sharing 1 pasture. All calves were inoculated at 12 weeks with Brucella abortus and infectious bovine rhinotracheitis vaccines, and at 13 weeks with a soluble O ostertagi L3 extract (sle). Infected and infected-treated calves had lower blood lymphocyte responses to phytohemagglutinin than did control calves at 2, 4, and 14 weeks, whereas the infected calves had higher responses at 6 and 8 weeks (P < 0.05). Responses to pokeweed mitogen followed a similar pattern, whereas those to sle were low in all calves. Infected and infected-treated calves had increased values of IgG1 to excretory-secretory antigens of L4 larvae, but no changes in the values of IgG1 to sle. They also had lower values of IgG and IgM to B abortus and antibodies to infectious bovine rhinotracheitis at 13 weeks. The infected-treated calves, however, had higher blood lymphocyte and monocyte counts and lower eosinophil count than did infected calves. They also had reduced abomasal mucosa thickness, abomasal wall weight, and abomasal lymph node weight than infected calves. It was concluded that O ostertagi causes nonspecific suppression of cellular and humoral immunity, hypersensitivity reactions coexisted with immunosuppression, and strategic anthelmintic treatments attenuated hypersensitivity reactions and initiated better immune responses.