bluuebunny/crossref_metadata_2025 huggingface dataset:
Growth kinetics of equine respiratory tract viruses in cell and organ cultures
Authors: O'Niell Fielding D. , Issel Charles J.
Published: February 2025

Growth kinetics of equine influenza virus-A1, equine herpesvirus-1, and equine rhinovirus-1 were determined in susceptible cell monolayers and in organ cultures of equine fetal tracheal and nasal turbinate epithelium. Equine influenza virus-A1 was replicated in cell and organ cultures and was released more readily and for longer periods from nasal turbinate epithelium than from tracheal epithelium. Equine herpesvirus-1 was also replicated in cell and organ cultures. During the first 24 hours after inoculation, equine herpesvirus-1 was released more readily from tracheal epithelium than from nasal turbinate epithelium. Beyond postinoculation day 1, virus was released more readily and for longer periods from nasal turbinate epithelium than from tracheal epithelium. Equine rhinovirus-1 replicated in cell and organ cultures, but almost exclusively from nasal turbinate epithelium.
Usefulness of lymphocyte typing to exclude incorrectly assigned paternity in horses
Authors: Bailey Ernest
Published: February 2025

Lymphocyte typing can be used to detect incorrectly identified parentage of horses. Efficacies of lymphocyte typing to solve paternity questions were calculated using gene frequency estimates of equine lymphocyte antigen (ela) markers for Thoroughbreds and Standardbreds. Probabilities that ela typing will detect an incorrectly assigned sire were 68.7% in Thoroughbreds, 67.9% in pacing Standardbreds, and 62.0% in trotting Standardbreds. These calculations demonstrate that ela typing is among the most efficacious genetic systems for solving paternity questions in horses. Likewise, it could also be effective for blood type identification and solving other questions of parentage in horses.
Efficacy of fenbendazole against inhibited larvae of Ostertagia ostertagi in yearling cattle
Authors: Williams J. C. , Knox J. W. , Marbury K. S. , Kimball M. D. , Scheide S. W. , Snider T. G. , David M. U.
Published: February 2025

Efficacy of fenbendazole, at doses of 7.5 and 10.0 mg/kg of body weight, against inhibited early 4th-stage larvae of Ostertagia ostertagi and other nematodes of the abomasum and intestinal tract, was investigated in naturally infected yearling heifers in late May 1982. In Louisiana, this is near the end of the period (March to May) in which maximal numbers of inhibition-prone larvae are acquired. The mean numbers of O ostertagi in 10 untreated control cattle were; adults, 4,880; developing 4th-stage larvae, 12,546; and inhibited early 4th-stage larvae, 167,931. At the 7.5 mg/kg dose level (10% liquid suspension) in 10 cattle, percentage reduction of O ostertagi in comparison with controls was; adults, 95.7%; developing 4th stages, 91.1%; and inhibited 4th stage, 55.0%. Percentage reductions of other genera were as follows; abomasum—Trichostrongylus axei, 99.6%; Haemonchus sp, 95.1%; intestinal tract—Cooperia spp, 97.8%; Trichostrongylus colubriformis, 100.0%; and Oesophagostomum radiatum 4th stage and adults, 100.0%. At the 10.0 mg/kg dose (10% liquid suspension) in 11 cattle, the percentage reduction of O ostertagi in comparison with controls was: adults, 98.6%; developing 4th stages, 92.9%; and inhibited 4th stage, 80.0%, Percentage reductions of other genera were; abomasum—T axei, 99.9%; Haemonchus sp, 98.8%; intestinal tract—Cooperia spp, 99.3%; T colubriformis, 100.0%; and Oes radiatum 4th stage and adults, 100.0%. Variability of efficacy against inhibited larvae was observed, particularly at the 7.5 mg/kg dose; at this dose, 7 of the 10 heifers in the group yielded in excess of 54,000 surviving larvae. Variability of efficacy was less evident at the higher dose; numbers of larvae > 40,000 were recovered from 2 of the 11 heifers in the group.
Auditory-evoked response in the clinically normal dog: Early latency components
Authors: Sims Michael H. , Moore Robert E.
Published: February 2025

Early latency components (0 to 10 ms) of the auditory-evoked response, which is also called the brainstem auditory-evoked response (baer), were recorded in 6 clinically normal adult dogs. Each dog responded to suprathreshold monaural clicks with a highly repeatable averaged waveform configuration consisting of 6 to 7 vertex positive waves. Configuration of the canine baer consisted mainly of waves I, II, III, V, and VI. Wave IV was present in some records, but in most cases, it formed a complex with wave III and was not apparent as a separate wave. After a 90-dB hearing level (hl) stimulus (20/s), the positive peak of wave I in the averaged response appeared at approximately 1 ms after stimulation onset, and subsequent waves were spaced at approximately ≤ 1-ms intervals. Amplitudes of these waves were 4.0 μV when measured from positive peak to the following negative trough.

Experiments were conducted to determine the effects of varying stimulus intensity (50- to 90-dB hl) on baer wave amplitude and peak latency in nonanesthetized and anesthetized dogs and to determine the effects of increasing stimulus rate (10 to 50/s) in nonanesthetized dogs. As stimulus intensity was increased in 10-dB steps from 50 to 90 dB and as the stimulus rate remained at 20/s, amplitude increased and latency decreased for all waves (P < 0.01). When stimulus intensity was held constant at 90 dB and stimulus rate increased from 5 to 50/s, amplitude decreased and latency increased. The amplitude effect was significant for all waves (P ≤ 0.01), whereas the latency effect was only significant for waves III (P ≤ 0.05) and waves V and VI (P ≤ 0.01), Thiamylal sodium (20 mg/kg of body weight, iv) significantly increased the latency of waves II and III (P ≤ 0.05) and waves V and VI (P ≤ 0.01), and decreased the amplitude of waves V and VI (P ≤ 0.01) across intensity levels.

The interpeak latency between the positive peaks of waves I and V was calculated from baer in nonanesthetized and anesthetized dogs. Interpeak latency was significantly decreased by decreasing stimulus intensity (P ≤ 0.05) and increased by the administration of thiamylal sodium (P ≤ 0.01). The difference in interpeak latency between right and left sides in nonanesthetized dogs was not affected by stimulus intensity between 50- and 90-dB hl.
Efficacy of ivermectin against the mange mite Sarcoptes scabiei var suis in pigs
Authors: Alva-Valdes R. , Wallace D. H. , Benz G. W. , Foster A. G. , Holste J. E.
Published: February 2025

The efficacy of ivermectin administered by esophageal intubation in a single dose was evaluated against the mange mite Sarcoptes scabiei var suis in 24 naturally infested pigs. Six pigs were allocated to each of the 4 treatment groups. Control (group 1) pigs were given nonmedicated water, group 2 were given ivermectin at 300 μg/kg of body weight, group 3 were given ivermectin at 400 μg/kg, and group 4 were given ivermectin at 500 μg/kg. The pigs were examined for S scabiei before treatment and on days 7, 14, 21, and 28 after treatment.

Of the 18 ivermectin-treated pigs, 10 had no live S scabiei recovered on day 7 after treatment, 16 had none on day 14, 18 had none on day 21, and 16 had none on day 28. All 6 nonmedicated control pigs had live S scabiei recovered on days 7 and 21, and 5 control pigs had mites on days 14 and 28.

The single administration of ivermectin given by esophageal intubation was highly effective in reducing the number of S scabiei at all dose levels tested. The pooled ivermectin-treated groups had significantly (P < 0.01) fewer mites than the control group on all posttreatment examination days. There were no statistically significant differences among the ivermectin dose levels.
A rapid staining procedure for Anaplasma marginale in bovine erythrocytes
Authors: Donovan-Myhand J. , Hart L. T. , Liu C. , Ohrberg C. , Seger C.
Published: February 2025

A commercial product that stains cells in < 1 minute was compared with the Giemsa and the Wright-Giemsa methods for detection of the intraerythrocytic parasite, Anaplasma marginale, in bovine blood smears. The total number of A marginale-infected erythrocytes detected in 5 microscope fields of 18 different samples was determined for each staining procedure. In samples where < 2% to > 25% of the rbc were infected, statistical analysis of the data indicated that the rapid staining method was superior to the Giemsa and Wright-Giemsa methods with regard to determination of the percentage of bovine erythrocytes infected with A marginale.
Spinal-evoked potentials and spinal conduction velocity of the cat: Reference values
Authors: Redding R. W. , Lee A. H. , Wilson S. G.
Published: February 2025

Spinal conduction velocities of the fastest afferent fibers of the spinal cord were calculated from the onset latencies of averaged evoked responses elicited by stimulation of the tibial nerve sensory afferent fibers and were recorded at various sites on the spinal cord. Locations for stimulation and recording electrodes were identified. Waveforms, mean amplitudes, and duration of the evoked spinal potentials were described. The mean conduction velocity of the spinal cord afferents at T12-T13 was 74.25 m/s with a sd of ± 9.81 m/s. The mean conduction velocity of the spinal cord afferents, determined at the cisterna magna, was 80.66 m/s with a sd of ± 11.50 m/s. This is a slight increase over the spinal conduction velocity at T12-T13 (P = 0.05).
Plasmid content and pathogenicity of Campylobacter jejuni and Campylobacter coli strains in the pregnant guinea pig model
Authors: Taylor Diane E. , Bryner J. H.
Published: February 2025

Strains of Campylobacter jejuni and C coli from human and animal sources were assessed for pathogenicity by their capability to produce abortions in pregnant guinea pigs. The pathogenicity rate varied from 7% to 87% for the C jejuni strains and from 0% to 53% for the C coli strains. Plasmid carriage was not found to correlate with pathogenicity as determined by ability of the strains to produce abortions in the pregnant guinea pig model.
Serologic and clinical responses of premunized, vaccinated, and previously infected cattle to challenge exposure by two different Anaplasma marginale isolates
Authors: Kuttler K. L. , Zaugg J. L. , Johnson L. W.
Published: February 2025

Two Anaplasma marginale isolates, one originating in Florida (FAM) and the other from Virginia (VAM), were compared immunologically by cross-challenge exposure of 14 Anaplasma carrier cattle, 8 previously infected cattle, and 6 splenectomized carrier calves. In addition, 28 cattle vaccinated with a commercially available adjuvant killed vaccine and 22 nonvaccinated cattle were challenge exposed with either FAM or VAM.

A detectable clinical response was not produced by either FAM or VAM challenge exposure in carrier and previously infected cattle; however, evidence of A marginale growth as characterized by low percentages of parasitemia and increased serum complement-fixation titers was seen in carrier cattle given a heterologous challenge organism and in previously infected cattle inoculated with either homologous or heterologous organisms. Among splenectomized calves, there was virtually no cross protection to the heterologous challenge exposure, whereas a homologous challenge failed to elicit any detectable response.

Vaccinated cattle were resistant to VAM exposure, but the clinical response to FAM exposure was severe with a 47% mortality. Most of these cattle displayed typical acute anaplasmosis that was only marginally less severe than that encountered in nonvaccinated cattle.
Effect of pH on in vitro ruminal conversion of l-tryptophan to 3-methylindole and indole
Authors: Hammond Andrew C. , Slyter Leonard L. , Carlson James R. , Wong Lap-Ping , Breeze Roger G.
Published: February 2025

Three in vitro experiments were conducted to determine the effects of pH on ruminal conversion of l-tryptophan (trp) to 3-methylindole (3-mi) and indole (ind). Experiment 1 involved 2 closed-system incubations, each with triplicate replications of buffered ruminal fluid at initial pH of 4.5, 5.0, 5.5, 6.0, 6.5, 7.0, 7.5, and 8.0. Highest molar conversions of trp to 3-mi were 61.5 ± 2.7% and 64.3 ± 0.8% at initial pH treatments of 7.5 and 7.0 (final pH 7.3 and 6.9) for the 2 incubations, respectively.

Experiment 2 used duplicate continuous cultures at each of 4 pH treatments. Following a common 5-day pretreatment period, effluent pH averaged 5.6, 6.1, 6.5, and 6.9 for the respective treatments. Data for 4 subsequent 5-day time periods showed production of 3-mi was affected by pH treatment (P < 0.01), time (P > 0.01), and treatment × time (P < 0.01); conversion of trp to 3-mi reached 78% at pH 6.9 and decreased to < 1% at pH 5.6. Production of ind was not related to pH treatment (P > 0.10). Total moles of volatile fatty acid (vfa) carbon produced showed a pH treatment × time interaction (P < 0.01) which reflected a trend toward decreasing vfa production at lower pH and increasing vfa production at higher pH.

Experiment 3 consisted of 2 pH treatments with additional continuous culture fermenters. Conversion of trp to 3-mi was lower (P < 0.01) at pH 6.6 than at pH 7.0 immediately after the pretreatment period, and this difference continued as a trend at subsequent times with 3-mi production at the lower pH remaining 67% to 76% of that of 3-mi production at the higher effluent pH. The decrease in 3-mi production at lower pH was not accompanied by a reduction in total vfa carbon produced in this experiment. There was a small difference in the conversion of trp to ind (P < 0.01) during the pretreatment period which continued for one time period after pH change. These data clearly demonstrate that ruminal degradation of trp is affected by pH and that ruminal conversion of trp to 3-mi is maximal at pH near neutrality and explain why treatment of cattle with buffers which raise ruminal pH has not resulted in reduction of ruminal 3-mi production.
Pharmacologie and pharmacokinetic properties of methocarbamol in the horse
Authors: Muir W. W. , Sams R. A. , Ashcraft S.
Published: February 2025

The hemodynamic, respiratory, and behavioral effects, as well as the pharmacokinetic properties of methocarbamol, were determined in horses. Heart rate, cardiac output, arterial and venous blood pressures, respiratory rate, and arterial blood gases did not change after iv methocarbamol (4.4, 8.8, 17.6 mg/kg) administration. There were no signs of behavior modification or ataxia observed.

Analysis of plasma concentration time data indicated that the disposition of methocarbamol may be dose-dependent. Clearance and steady-state volume of distribution decreased as the dose increased. Plasma concentrations of guaifenesin, a metabolite of methocarbamol, were never greater than 0.5% of the plasma concentration of methocarbamol.
Diagnostic criteria for an enzyme-linked immunosorbent assay for occult heartworm disease: Standardization of the test system in naturally exposed dogs
Authors: Gillis Jaqueline M. , Smith Ronald D. , Todd Kenneth S.
Published: February 2025

The development of criteria for interpreting and reporting the results of an occult heartworm enzyme-linked immunosorbent assay to practitioners is described. The antigen is a saline extract of adult female Dirofilaria immitis. The cutoff absorbance A400 nm values were estimated, using 106 dogs free of infection. Any A400 nm value < 0.526 is considered negative and values ≥ 0.784 are positive. Intermediate A400 nm values are interpreted as suspect. Absorbance values for serum samples from 13 client-owned amicrofilaremic dogs revealed a bimodal distribution consistent with presumptive diagnosis based on clinical signs, which indicates that the test may be used to support a diagnosis of occult heartworm disease. The present serotest, however, is unable to distinguish microfilaremic dogs from noninfected dogs. Serum from dogs infected with other common helminths failed to crossreact with the D immitis antigen, with the exception of Dipetalonema reconditum.
1,3 Butanediol treatment of ethylene glycol toxicosis in dogs
Authors: Murphy Michael J. , Ray Allen C. , Jones Larry P. , Reagor John C.
Published: February 2025

In order to assess the therapeutic value of 1,3 butanediol in ethylene glycol toxicosis, mixed-bred dogs were given an oral dose of commercial antifreeze at 6 ml/kg of body weight (0 hour) and treated (iv) 7 times at 6-hour intervals with 5.5 ml/kg of body weight 1,3 butanediol solution (20% in physiological saline solution) beginning at 8, 12, and 21 hours. Serum glycolic acid concentration was quantitated by high-pressure liquid chromatography. Three dogs that were given ethylene glycol, but no 1,3 butanediol treatment, died with elevated serum glycolic acid concentrations. Five dogs were given ethylene glycol and 1,3 butanediol treatment. Of 2 dogs treated at 8 hours, 1 survived and 1 died at 39 hours; 1 treated at 12 hours and 1 treated at 21 hours survived; 1 dog died soon (27 hours) after treatment was initiated at 21 hours. Four of the 5 dogs had dramatically decreased serum glycolic acid concentrations after 1,3 butanediol treatment, indicating its effectiveness in inhibiting alcohol dehydrogenase-dependent glycolic acid formation in vivo.
Use of whole blood lymphocyte stimulation test for immunocompetency studies in bald eagles, red-tailed hawks, and great horned owls
Authors: Redig Patrick T. , Dunnette Jean L. , Sivanandan Vaithianathan
Published: February 2025

Mitogen-induced whole blood lymphocyte stimulation tests for immunocompetency studies in bald eagles (Haliaeetus leucocephalus), red-tailed hawks (Buteo jamaicensis), and great horned owls (Bubo virginianus) were developed. Combinations of incubation times, blood dilutions, concentrations of [3H]thymidine and [125I]2-deoxyuridine, antibiotics, phytohemagglutinin-P, and concanavalin A were tested for their effects on the stimulation index (si).

An antibiotic combination of gentamicin plus amphotericin B yielded low si with lymphocytes from bald eagles, but not with lymphocytes from great horned owls or red-tailed hawks. Penicillin plus streptomycin caused no such depression of si. Lymphocytes from all 3 species yielded maximum responses with a 48-hour prelabel and 12- to-16 hour postlabel incubation period at 41 C and 1:20 blood dilution. Optimal mitogen concentrations for lymphocytes from bald eagles, red-tailed hawks, and great horned owls were 25 μg, 10 μg, and 10 μg of phytohemagglutinin-P/well, respectively, and 2.5 μg, 10 μg, and 10 μg of concanavalin A/well, respectively. Differences in si were not seen between the 2 radioactive labels. The optimal concentration of the [3H]thymidine label ranged from 0.06 to 0.125 μCi/well.
Associations of sire, breed, birth weight, and sex in pigs with congenital splayleg
Authors: Vogt D. W. , Gipson T. A. , Akremi B. , Dover Sam , Ellersieck M. R.
Published: February 2025

Data on 4,411 male and 4,148 female progeny from the University of Missouri-Columbia swine research herd were analyzed to evaluate the associations of sire, breed, weight at birth, and sex of the pigs with the development of congenital splayleg. Statistically significant differences in frequency of splayleg were found among sires and among breeds indicating a genetic influence. Differences in frequencies among male vs female progeny also were found to be statistically significant. The overall frequency among male progeny was 1.74 times that observed among female progeny. Comparison of birth weights of splayleg vs normal pigs showed birth weights to be statistically significantly smaller among affected pigs.
Coagulation changes in African swine fever virus infection
Authors: Edwards J. F. , Dodds W. J. , Slauson D. O.
Published: February 2025

Pigs were infected with highly virulent (Tengani ’62), with moderately virulent (DR ‘79) African swine fever (asf) virus, or with virulent hog cholera (hc) virus. Changes in platelet counts, selected coagulation assays and concentrations of factor VIII-related antigen (VIIIR:Ag) were monitored. Permeability of aortic endothelium was studied after the injection of Evan's blue dye on various days after infection with DR ‘79 asf virus.

Virulent asf virus caused prolongation of the activated partial thromboplastin time (aptt), 1-stage prothrombin time, and thrombin clotting time as early as postinoculationday (pid) 4. These changes became progressively more severe until death. Both virulent hc and DR’79 viruses induced an increase appt and thrombin clotting time at pid 3 to 4, only occasionally did the prothromb in time increased significantly (P < 0.01). The appt began to decrease on pid 7 and 8, but only DR’79-infected pigs lived long enough to regain a normal aptt. Infection by asf viruses caused acute thrombocytopenia after pid 6 and platelet counts of hc virus-infected pigs decreased progressively from the onset of fever to levels of 1 to 2 × 105/mm3 at pid 6 to 7. All asf virus-infected pigs had an increase in VIIIR:Ag beginning at pid 3, with maximum increases at pid 6 to 7. Hog cholera virus infection did not cause consistent changes in levels of VIIIR:Ag.

Pigs infected with DR’79 virus did not have increased vascular permeability to Evan's blue dye during infection; however, there was markedly decreased staining of the aorta after pigs became thrombocytopenic.
Prevalence of gastrointestinal parasitism in Oklahoma swine
Authors: Morris Robert G. , Jordan Helen E. , Luce William G. , Coburn Timothy C. , Maxwell Charles V.
Published: February 2025

The prevalence of swine gastrointestinal parasites was determined from all listed large swine operations (28) and a geographically representative sample (70) of the population of small hog farm operations in Oklahoma. Fecal samples (n = 975) were collected from 98 farms. From the 98 farms, parasites were recovered in pig feces as follows: Ascaris, 53.0%, strongyles, 53.1%, Trichuris, 35.7%, spirurids, 6.1%, Strongyloides, 19.4%, coccidia, 57.1%, and Balantidium, 55.1%. A higher percentage (16.5%) of hogs maintained on cement floors were positive for Ascaris than were those on either dirt lots (11.9%) or slatted floors (9.9%), but pigs on dirt lots were more often positive with a higher percentage of coccidia (21.0%) than those on either cement or slatted floors (8.5% and 6.0%, respectively). Prevalence of Trichuris was essentially the same (6.8% to 11.3%) in hogs from all 3 management practices.
Oronasal and intramuscular vaccination of swine with a modified live porcine parvovirus vaccine: Multiplication and transmission of the vaccine virus
Authors: Paul Prem S. , Mengeling William L.
Published: February 2025

An attenuated strain NADL-2 of porcine parvovirus (ppv) has been used at the 54th cell culture passage as a modified live-virus (mlv) vaccine. The present study was conducted to determine the minimum immunizing dose of mlv, the extent of mlv multiplication in swine tissues, and its transmission from swine administered mlv oronasally or intramuscularly. Immune response to mlv was dose dependent and swine responded to as little as 102 median cell-culture infective doses (ccid50). A 105 ccid50 of mlv, the largest dose given, induced the best immune response and was used in subsequent experiments.

Route of mlv administration also was found to be important. The mlv replicated in tissues of swine after im inoculation; however, viral antigen in tissues was less, as measured by immunofluorescence, and serum hemagglutination-inhibition titers for ppv were lower in mlv-inoculated swine than we have previously observed in virulent ppv-inoculated swine. In contrast, oronasal inoculation with mlv did not consistently result in infection of pigs; only 5 of 23 swine had virologic and/or serologic evidence of infection. Virus transmission studies indicated that mlv is shed in feces, but shedding occurs later than that in virulent-ppv-inoculated swine and is inconsistent. Delayed transmission of mlv was observed in contact pigs, which were seronegative at 2 weeks, but became seropositive at 4 weeks—indicating that perhaps a virus population capable of infecting pigs by oronasal route was selected by passage through the pig. The mlv also was found to be safe for pregnant gilts, since transplacental infection of fetuses was not observed after oronasal or after oronasal and im inoculation. The virulent strain NADL-8 of ppv retained its capability to cause transplacental infection after 10 cell-culture passages, indicating that perhaps the inability of strain NADL-2 to cause transplacental infection may be inherent to this strain. Our current and previous investigations attest to the attenuation of strain NADL-2 of ppv and demonstrate the strain's usefulness as a mlv vaccine for protection against the ppv-induced reproductive failure.
Transplacental transfer and colostral concentrations of selenium in beef cattle
Authors: Koller Loren D. , Whitbeck Ginny A. , South Peter J.
Published: February 2025

Three groups of 20-month-old pregnant Hereford heifers received 3 regimens of selenium (Se) supplementation. Group 1 received pelleted alfalfa hay, soybean meal, which contained Se (0.313 mg/kg), and 90 mg of Se as sodium selenite/kg of salt-mineral mix ad libitum. Group 2 received the pelleted hay and soybean meal, and group 3 received only the pelleted alfalfa hay. At time of parturition, the mean whole blood Se concentrations were; group 1 = 0.250 mg of Se/kg of blood, group 2 = 0.162 mg/kg, and group 3 = 0.052 mg/kg, whereas the respective mean blood glutathione peroxidase (GSH-Px) values were 144, 80, and 30 mU/mg of hemoglobin. In comparison, the mean whole blood Se values for the calves were 0.242, 0.175, and 0.81 mg/kg, respectively, and their blood GSH-Px values were 154, 113, and 50 mU/mg of hemoglobin, respectively. Thus, the blood Se and GSH-Px values for each group reflected dietary intake of Se. The calf blood GSH-Px values were similar to their dams for group 1, but were 41% higher in group 2 and 67% greater in group 3. The data suggested that the fetus can sequester blood Se, accumulating values greater than the dam, and that larger amounts were concentrated in the fetus when smaller amounts were available from the dam.

The colostrum contained modest to low amounts of Se proportionate to dietary intake of this element. However, milk 7 days after parturient contained inadequate amounts of Se to sustain blood Se values in calves and the milk from heifers with low normal blood Se was essentially void of Se (0.009 mg/kg).

Assessment of blood GSH-Px in calves 8 weeks of age revealed that Se intake was insufficient to maintain blood GSH-Px corresponding to activity at birth; the declines were 17% in group 1, 29% in group 2, and 36% in group 3. Thus, the calves from the heifers that possessed the lowest blood Se (group 3) had the most rapid decline in blood GSH-Px.

The fetus can sequester Se when the dam has relatively low blood values of this element. Initially, an additional amount can be consumed by the neonate via colostrum, but the milk rapidly becomes deficient in Se. Lack of an adequate dietary source of Se resulted in a rapid decline of calf blood GSH-Px activity by 8 weeks of age. Nevertheless, oral supplementation of Se will result in sufficient quantities of this element in the dam with effective transfer to the fetus in utero to provide the neonate with adequate blood Se to prevent the development of severe Se-deficient associated syndromes.
Bovine pneumonic pasteurellosis: Effect of vaccination with live Pasteurella species
Authors: Panciera R. J. , Corstvet R. E. , Confer A. W. , Gresham C. N.
Published: February 2025

Experimental bovine pneumonic pasteurellosis was induced in beef calves by a transthoracic challenge exposure with Pasteurella haemolytica serotype 1 or P multocida type 3. Challenge exposure lesions were quantified by a lesion scoring system based on size and extension of lesions with larger scores assigned to the more severe lesions. Calves inoculated with live Pasteurella sp by aerosol or parenteral routes developed high serum antibody titers to the homologous organism, as determined by a quantitative fluorometric procedure. Mean lesion scores were approximately 2 to 20 times higher in control than those in vaccinated calves. There was a significant correlation (P < 0.05) between high serum antibody titers at the time of challenge exposure and a low lesion score in 4 of 6 experiments.
Application of the enzyme-linked immunosorbent assay for the detection of platelet antibodies in dogs
Authors: Campbell Karen L. , George Jeanne Wright , Greene Craig E.
Published: February 2025

An enzyme-linked immunosorbent assay (elisa) was developed to detect serum antibodies reactive to canine platelets. The method used an anti-canine immunoglobulin G horseradish peroxidase conjugate, O-dianisidine, as a water-soluble chromagen, and pooled platelets as a temporary antibody support. The elisa was compared with a conventional immunoinjury method measuring the accelerating effect of platelet factor 3 on coagulation. The elisa was more sensitive in the detection of antiplatelet antibodies in canine patients with idiopathic thrombocytopenic purpura, autoimmune hemolytic anemia, and systemic lupus erythematosus. Serial dilution of rabbit anti-canine platelet serum revealed a positive correlation between the strength of the antiserum and the degree of color measured spectophotometrically, indicating that the absorbance value may be useful in estimating the amount of antibody present in the serum in indirect tests and on the platelets in direct tests.
Pathogenicity studies of feline coronavirus isolates 79-1146 and 79-1683
Authors: Pedersen Niels C. , Evermann James F. , McKeirnan Alison J. , Ott Richard L.
Published: February 2025

Two feline coronavirus isolates were characterized by their disease-causing potential in cats. The 79-1683 feline coronavirus isolate caused an inapparent-to-mild enteritis when given oronasally to specific-pathogen-free kittens and was not a cause of feline infectious peritonitis (fip). Target tissues for the virus were the mature apical epithelium of the small intestine, mesenteric lymph nodes, tonsils, thymus, and (to a lesser extent) the lungs. Inoculated kittens shed high numbers of virus in their feces for 14 to 17 days, but remained infectious to susceptible kittens for longer periods of time, as evidenced by contactexposure studies. Because the 79-1683 isolate induced only enteritis, it was designated feline enteric coronavirus (FECV) 79-1683.

The 79-1146 feline coronavirus isolate induced effusive abdominal fip in specific-pathogen-free kittens after oronasal and intraperitoneal inoculation. Clinical signs of disease appeared within 12 to 14 days in almost all inoculated kittens. Because this isolate caused fip, it was designated fip virus (FIPV) 79-1146.

Cross-protective immunity was not induced by the various coronavirus infections. Kittens preimmunized with the UCD strain of FECV (FECV-UCD) or with FECV-79-1683 were not immune to infection with FIPV-79-1146. Likewise, kittens previously inoculated with FECV-79-1683 were not immune to infection with FIPV-UCD1. In fact, preexisting heterologous FECV-79-1683 immunity often accelerated and enhanced the severity of disease caused by inoculation with FIPV-UCD1, This enhancing effect was not seen, however, when FECV-UCD and FECV-79-1683 immune cats were challenge exposed with FIPV-79-1146. The FIPV-79-1146 caused disease only after an incubation period of 12 to 14 days, regardless of whether or not the kittens had preexisting feline coronavirus immunity and regardless of what FECV strain was used to induce that immunity. One kitten that recovered from FECV-79-1683 was immune to FIPV-79-1146 infection, and a second such kitten developed fip.
Characterization of antigenic variation among mink enteritis virus isolates
Authors: Parrish C. R. , Gorham J. R. , Schwartz T. M. , Carmichael L. E.
Published: February 2025

Three antigenic forms of natural field isolates of mink enteritis virus were revealed with a panel of monoclonal antibodies generated against the closely studied feline panleukopenia virus and canine parvovirus-2 virus. Two types (types 2 and 3) were shown to be closely related by agar-gel precipitin tests and by restriction enzyme mapping. However, types 2 and 3 differed from the type 1 isolates in the same tests. In cross-protection studies, inactivated viral vaccines made from any one of the 3 variant types of mink enteritis virus protected mink against challenge exposure by the homologous, as well as the heterologous, antigenic types.
Relationship between fertility and blood glucose and cholesterol concentrations in Holstein cows
Authors: Kappel L. C. , Ingraham R. H. , Morgan E. B. , Zeringue Laura , Wilson Deborah , Babcock D. K.
Published: February 2025

Jugular blood samples were collected prepartum and postpartum from 97 Holstein cows and heifers. Samples were analyzed for total serum cholesterol and plasma glucose. Plasma samples taken 4, 11, 18, and 25 days postpartum were also analyzed for progesterone. Concentrations of cholesterol, glucose, and progesterone were evaluated in relation to summer- and winter-calving seasons, milk production, lactation number, days-to-conception, number of postcalving uterine infusions given, and time relative to calving. A temperature-humidity index was used as a covariate in the analysis to adjust the data for climatic effects so that seasonal effects other than temperature and humidity could be determined.

Average plasma glucose was within the normal range (62 ± 8 mg/dl). It increased before calving and then declined to a minimum value between 11 and 25 days postpartum. Glucose then increased after 25 days for the summer-calving group and remained relatively stable for the winter-calving cows. Blood glucose concentrations were inversely related to milk production. Negative correlations existed between milk production and plasma glucose at days 4, 11, 18, 25, and 39 postpartum. First-lactation heifers had higher blood glucose levels than cows in their second or later lactation. Blood glucose concentrations were not related to days-to-conception over both seasons.

Average serum cholesterol was within the normal range (125 ± 29 mg/dl). It decreased before calving and then increased for 88 days after calving. Summer-calving cows had higher serum cholesterol concentrations prepartum and winter-calving cows had higher concentrations from 39 through 88 days postpartum. Cholesterol concentrations were directly related to milk production from 25 through 88 days postpartum. Cows in their second lactation had higher cholesterol concentrations than firstcalf heifers on 9 of 12 sampling days. Cows in their third or later lactation had intermediate cholesterol concentrations. Days-to-conception was inversely related to serum cholesterol. Cholesterol values were not related to number of postcalving uterine infusions. Plasma progesterone was positively correlated with cholesterol in the summer-calving group.
Enzyme-linked immunosorbent assay, using monoclonal antibody, to detect enterotoxic Escherichia coli K99 antigen in feces of dairy calves
Authors: Holley Deborah L. , Allen Stanley D. , Barnett Bill B.
Published: February 2025

A modified, double-antibody, enzyme-linked immunosorbent assay (elisa) was developed to detect the K99 pilus antigen of enterotoxic Escherichia coli (etec) in feces of calves. Extremely high positive to negative ratios (> 200) were obtained by using monoclonal antisera as the primary antibody. Strong positive reactions were obtained with strains of E coli known to produce the K99 antigen; however, nonenteropathogenic E coli (strains not producing the K99 antigen), Salmonella, Proteus, Klebsiella, Pseudomonas, Staphylococcus, Streptococcus, and rotavirus produced negative results.

Seventy-five fecal samples, 8 from healthy calves and 67 from calves with neonatal calf diarrhea were examined with the K99 elisa for the presence of etec. Rotavirus test and fecal culture results were available on feces from calves with diarrhea and were used with the K99 elisa results to determine the specific cause of the disease. Enterotoxic E coli was the predominant agent detected in the feces of 29 diarrheal calves < 5 days of age. Mixed infections of rotavirus and etec were also common in these calves, but rotavirus infections alone were not detected. In 38 calves ≥ 5 days, rotavirus was detected without etec. Of these calves, only 2 produced positive tests with the K99 elisa Salmonella sp and Proteus sp were detected from 5 of 67 calves with diarrhea.
Effect of prior natural exposure to Pasteurella haemolytica on resistance to experimental bovine pneumonic pasteurellosis
Authors: Confer A. W. , Panciera R. J. , Fulton R. W.
Published: February 2025

The effect of prior natural exposure to Pasteurella haemolytica, as determined serologically, was studied with respect to resistance to experimental pneumonic pasteurellosis in 20 calves from 3 experiments. Resistance to challenge exposure was measured using a lesion-scoring system. As measured by a quantitative fluorometric immunoassay, naturally acquired serum antibody titers to the organisms were 0 to 228. There was a significant correlation (P < 0.05) between high naturally acquired antibody titers and resistance to transthoracic challenge exposure with P haemolytica.
Specificity of pseudorabies virus serotests
Authors: Neill J. D. , Kelling C. L. , Rhodes M. B.
Published: February 2025

Pigs experimentally inoculated with bovine herpesvirus-1 or equine herpesvirus-1 developed mild clinical disease signs. Regression of clinical disease was accompanied by development of specific virus-neutralizing antibodies. These antibodies did not react positively with pseudorabies antigens in the serumvirus neutralization test, an indirect radioimmunoassay, or a microimmunodiffusion test.
Detection of Corynebacterium equi-specific antibody in horses by enzyme-linked immunosorbent assay
Authors: Hietala S. K. , Ardans A. A. , Sansome A.
Published: February 2025

An enzyme-linked immunosorbant assay was developed to measure naturally occurring Corynebacterium equi specific antibody in horse serum. Antibody against C equi was demonstrated in normal adults and was passively transferred to foals. Adult levels of specific antibody were reached by 5 to 6 months of age in healthy foals. Decreased early antibody levels were demonstrated in a limited number of foals with confirmed C equi infection.
Fatigue characteristics and biocompatability of a totally implantable bone growth stimulator in ponies
Authors: Collier M. A. , Lowe J. E. , Rendano V. T.
Published: February 2025

Materials fatigue and gross biocompatability of an implantable bone growth stimulator (bgs) were assessed in a 6-month trial using 6 ponies. The forelegs of each pony were implanted with a bgs; the right leg implant had the cathode and cathode lead preconnected by the manufacturer, and the left leg implant was connected at surgery. Evaluation was by radiographic and clinical examination at the beginning and end of the experimental period. Six of the 12 cathode leads (50%) and 7 of the 12 cathodes (58%) were broken at 6 months. All of the implanted preconnected cathode and insulated cathode leads and 33.3% of the surgically connected cathodes and insulated cathode leads were connected at the titanium connector socket at 6 months. This bgs may exhibit wire fatigue > 50% of the time when used in the distal extremity of the horse.
Comparison of the pneumopathogenicity of two strains of bovine viral diarrhea virus
Authors: Potgieter L. N. D. , McCracken M. D. , Hopkins F. M. , Guy J. S.
Published: February 2025

The pneumopathogenicity in calves of 2 strains of bovine viral diarrhea (bvd) virus, isolate 2724 (a noncytopathogenic virus) and isolate 72 (a cytopathogenic virus), was compared. All calves were inoculated endobronchially, using fiberoptic bronchoscopy.

Two calves were given Pasteurella haemolytica, 2 calves were given the noncytopathogenic bvd virus, and 2 calves were given cytopathogenic bvd virus. Five calves were inoculated sequentially with bvd virus and, 5 days later, with P haemolytica. Two of these calves were inoculated with the noncytopathogenic bvd virus and the other 3 with the cytopathogenic strain.

Both bvd virus strains caused marked respiratory tract disease in the calves sequentially inoculated with P haemolytica and also impaired pulmonary clearance of P haemolytica. However, the effect of the cytopathogenic strain was more severe than the noncytopathogenic strain, indicating that strains of bvd virus may vary in their pneumopathogenicity for calves.
Venous blood pressure relative to the development of bovine udder edema
Authors: Vestweber Jerome G. E. , Al-Ani Falah K.
Published: February 2025

Cranial superficial epigastric (milk vein) and jugular venous blood pressure were measured in 8 cows with udder edema and in 3 normal control cows at least 2 weeks before parturition, at parturition, and 2 weeks after parturition. Cows with udder edema had a significant mean increase (P ≤ 0.05) in cranial superficial epigastric venous pressure at parturition when compared with pressures 2 weeks prepartum and 2 weeks postpartum. Unaffected control cows had an insignificant increase in cranial superficial epigastric venous pressure during these 3 periods of measurement. There was an insignificant increase in jugular venous blood pressure during the 3 periods of measurement in affected and control cows. A correlation was observed between mammary blood flow and cranial superficial epigastric blood pressure at parturition (r = −0.659, P ≤ 0.05).
Adenosine triphosphatase activity in the carotid rete-cavernous sinus complex of sheep and goats
Authors: Khamas Wael A. , Ghoshal Nani G.
Published: February 2025

The carotid rete-cavernous sinus structures of sheep and goats were frozen with liquid nitrogen or with Freon liquid spray and were cryosectioned at −20 C.

The main concentration of sodium- and potassium-dependent adenosine triphosphatase was on the tunica intima, especially on the endothelial cells of rete branches and the cavernous sinus. Little reaction product was discernible in the tunica media and the tunica adventitia.
Antiepithelial autoantibodies associated with the feline eosinophilic granuloma complex
Authors: Gelberg H. B. , Lewis R. M. , Felsburg P. J. , Smith C. A.
Published: February 2025

A retrospective study of banked sera from 19 cats with the eosinophilic granuloma complex revealed that 68% of affected cats had circulating antibodies to components of normal cat epithelium. Seemingly, the eosinophilic granuloma complex of cats may be an autoimmune disease; however, epidermal damage caused by the eosinophilic granuloma complex may release altered self-antigens to which the cat's immune system responds.
Amaranthus retroflexus (redroot pigweed): Inability to cause renal toxicosis in rabbits
Authors: Schamber G. J. , Misek A. R.
Published: February 2025

Rabbits fed Amaranthus retroflexus (redroot pigweed) did not develop lesions of renal toxicosis reported in other species fed this plant. In feeding trials using adult and weanling rabbits, A retroflexus did not produce indications of renal involvement in rabbits. In both trials, treated rabbits had increased weight loss when compared with controls; however, the weight loss was not attributed to a toxic effect, but to previously described decreased palatability of Amaranthus spp.
Comparative evaluation of a commercial microdilution method and a conventional disk diffusion method for determination of antibiograms of gram-positive cocci
Authors: Newman Susan S. , Roy Alma F. , Luther D. Gene , Hoskins Johnny D. , Cox Hollis Utah , Kearney Michael T.
Published: February 2025

A commercial broth microdilution system for testing the antimicrobial susceptibility of gram-positive cocci was compared with the standardized disk agar-diffusion method by testing 254 clinical strains of staphylococci and streptococci using both methods. A total of 2,794 parallel determinations were made with 92.3% complete agreement between the 2 methods; of the discrepancies encountered, 3.0% were minor, 2.5% were major, and 2.1% were very major. The results indicate that the commercial microdilution system may provide a reliable quantitative method for antimicrobial susceptibility testing of clinical isolates from animals.
Colonic motor responses in the pony: Relevance of colonic stimulation by opiate antagonists
Authors: Roger Th. , Bardon Th. , Ruckebusch Y.
Published: February 2025

The electrical and mechanical activity of the digestive tract and its response to the administration of opiate agonists and antagonists was assessed from electrodes and strain gauges chronically implanted on the jejunum and the cecocolonic segments in 3 ponies given a diet of hay and concentrates. Before the drugs were given, 10 to 17 migrating myoelectric complexes/day were recorded on the small intestine, and a rhythmic motor activity (base line) was observed on the proximal portion of the colon at the rate of 3.5 to 6.6/hour, Propagated contractions from the proximal to the distal portion of the colon occurred at the rate of 1.5 to 2.3/hour.

Each pony was used as its own control and was given morphine (0.5 or 1 mg/kg of body weight, iv) or fentanyl (0.01 or 0.05 mg, iv) at weekly intervals. After an early phase of inhibition of the overall activity that lasted from 0.5 to 3 hours, depending on the dose, the resting muscle tone of the colonic activity was increased for a dose-dependent period. Propagated contractions only reappeared at the end of this 2nd phase.

The opiate antagonist naloxone (0.5 mg/kg, iv) elicited a marked propulsive activity on the left replicated colonic segment, characterized by an increase in the number of propagated contractions. The N-methyl-quaternary analog of naloxone (methylnaloxone, which presumably entails selective action at opiate receptors outside the cns) was also effective, indicating peripheral effects at the dosage level used (0.5 mg/kg, iv). Seemingly, an inhibitory opioid system exists in the control of colonic motor function in ponies and the possible usefulness of opiate antagonists to relieve hypomotility resulting in colonic impaction and constipation.
Dairy herd problem with mastitis caused by a rapidly growing Mycobacterium species
Authors: Schultze W. Donald , Stroud Ben H. , Brasso William B.
Published: February 2025

Intramammary infections by a nonspeciated Mycobacterium of Runyon group IV increased in the dairy herd at the Beltsville, Md, Agricultural Research Center during 4 years, and were cultured from 9.7% of 300 quarter samples from clinical mastitis cases in 1982. The infection was mildly acute, without systemic involvement, and refractory to therapy but self-terminating, usually at the end of lactation. Invasion of the mammary gland commonly followed stress, either calving or previous clinical mastitis, and was most frequent in August and September. Transmission of this mycobacterial intramammary infection from cow to cow was far more likely in free-stall barns than in tie stalls, and seemed not to be associated with machine milking.
Adhesion of Corynebacterium renale and Corynebacterium pilosum to epithelial cells of bovine vulva
Authors: Hayashi A. , Yanagawa R. , Kida H.
Published: February 2025

Corynebacterium renale and C pilosum adhered effectively to the epithelial cells of the bovine vulva; the numbers of these organisms that adhered to the vulval epithelial cells were 50 and 30/cell, respectively, which were several times as many as those that adhered to the uroepithelial cells. Of the epithelial cells of the vulva, cornified cells lacking nuclei bound more bacteria than did those with indistinct nuclei, indicating that adhesion of bacteria was most effective to the most aged cells. The marked adhesion of C renale and C pilosum to the epithelial cells of the vulva may indicate that the vulva is an important portal of entry of these bacteria.
Bovine-murine hybridoma that secretes bovine monoclonal antibody of defined specificity
Authors: Raybould T. J. G. , Crouch C. F. , McDougall L. J. , Watts T. C.
Published: February 2025

Spleen cells from a calf hyperimmunized with bovine enteric coronavirus were fused with nonproducer mouse plasmacytoma cells. Stable hybridoma lines secreting bovine immunoglobulins were obtained. One line secreted monoclonal bovine immunoglobulin G2, which reacted specifically with bovine enteric coronavirus in an enzyme-linked immunosorbent assay, inhibited virus hemagglutination, and precipitated a structural polypeptide with a molecular weight of 26,000 daltons.