bluuebunny/crossref_metadata_2025_split huggingface dataset:
Efficacy of an in-feed ivermectin formulation against gastrointestinal helminths, lungworms, and sarcoptic mites in swine
Authors: Alva-Valdes R. , Wallace D. H. , Foster A. G. , Ericsson G. F. , Wooden J. W. 
Published: February 2025

SUMMARY
The efficacy of ivermectin as an in-feed formulation was evaluated against naturally acquired gastrointestinal helminths, lungworms, and sarcoptic mites (experiment 1; n = 24) and against induced infection with intestinal nematodes (experiment 2; n = 24) in pigs. Treatments consisted of ivermectin administered in feed at concentrations calculated to provide 100 or 200 μg/kg of body weight/d for 7 days or of nonmedicated feed (controls) for 7 days.
At concentration of 100 μg of ivermectin/kg/d, efficacy against naturally acquired infections was 97.7% for Ascaris suum, 97.8% for Metastrongylus spp, > 99% for Oesophagostomum spp, 100% for Macracanthorhynchus hirudinaceus, and 89.7% for Ascarops strongylina. Against induced infections (fourth-stage larvae), efficacy was 100% for A suum and 96.9% for Oesophagostomum spp.
At concentration of 200 μg of ivermectin/kg/d, efficacy against naturally acquired infections was 100% for A suum, Hyostrongylus rubidus, Metastrongylus spp, and Ascarops strongylina; > 99% for Oesophagostomum spp; and 85.9% for Macracanthorhynchus hirudinaceus. Against induced infections (fourth-stage larvae), efficacy was 100% for A suum and 95% for Oesophagostomum spp.
At concentrations of 100 and 200 μg of ivermectin/kg/d, efficacy against Sarcoptes scabiei var suis was evidenced by elimination of the mite by posttreatment day 14.
Cross-protective immunity between equine encephalomyelitis viruses in equids
Authors: Walton Thomas E. , Jochim Michael M. , Barber T. Lynwood , Thompson Lee H. 
Published: February 2025

SUMMARY
Eighteen equids were inoculated with eastern equine encephalomyelitis (eee) and 18 equids with western equine encephalomyelitis (wee) viruses to produce eee virus- and wee virus-immunized equids. Twelve surviving eee virus-seropositive equids, 15 surviving wee virus-seropositive equids, and 10 nonimmunized, seronegative equids (controls) were subsequently inoculated with an equine pathogenic (epizootic) strain of Venezuelan equine encephalomyelitis (vee) virus to determine cross-protective immunity. Challenge infection produced 90% mortality in control (nonimmunized) equids, and 40% mortality in wee virus-seropositive equids; all eee virus-seropositive equids survived. Postchallenge exposure vee viremia levels in eee virus- or wee virus-seropositive equids were lower than those in the 10 nonimmunized vee virus-inoculated control equids. Plaque-neutralizing antibody responses to vee virus in the eee virus- and wee virus-seropositive equids were similar in time of onset and titer to the antibody responses of nonimmunized equids. Neutralizing antibody to the third equine encephalomyelitis virus (either eee virus or wee virus) was detectable in 19 of 27 equids after inoculation with the challenge virus, vee. Demonstration of cross-protective immunity between eee or wee virus and vee virus in equids confirmed field observations made during the vee epizootic in Texas in 1971.
Characterization of the attachment of Treponema hyodysenteriae to Henle intestinal epithelial cells in vitro
Authors: Bowden Christine A. , Joens L. A. , Kelley L. M. 
Published: February 2025

SUMMARY
Propertess of the attachment of Treponema hyodysenteriae to Henle intestinal epithelial (hie 407) cells were examined. The frequency of attachment depended on the motility and viability of the spirochetes. Rabbit hyperimmune and swine convalescent antisera inhibited attachment. Treatment of hie cells with neuraminidase had no effect on attachment; however treatment of spirochetes with the enzyme decreased adherence significantly (P = 0.01). Attachment was inhibited by N-acetylneuraminic acid, d-glucuronic acid, and fetuin. Adherence was increased following coincubation with N-acetylglucosamine or yeast mannan. Surface antigens of T hyodysenteriae, isolated by chemical extraction, competitively inhibited adherence. Concentrated T hyodysenteriae culture supernatant fractions inhibited adherence, but concentrated phosphate buffered-saline washings of the spirochete and concentrated uninoculated media did not inhibit adherence. Sialic acid was detected in unwashed T hyodysenteriae and spent culture supernatant fractions in higher concentrations than from washed spirochetes and uninoculated media. It was concluded that the binding adhesins on T hyodysenteriae for cultured hie cells may contain sialic acid residues.
Effect of surgical manipulation, placental fluid, and flunixin meglumine on fetal viability and prostaglandin F2α release in the gravid uterus of mares
Authors: Pascoe David R. , Stover Susan M. 
Published: February 2025

SUMMARY
Twenty-one pregnant mares with single or twin conceptuses between 41 and 65 days of gestational age were allotted to 5 treatment groups. A ventral median celiotomy was performed in all mares. In group-1 mares (3 mares, single conceptus), the uterus and fetus were palpated for 5 minutes. In group-2 mares (3 mares, single conceptus, flunixin meglumine), 250 ml of sterile placental fluid was injected into the nongravid uterine horn. In group-3 mares (4 mares, unicornuate twin conceptuses), group-4 mares (3 mares, unicornuate twin conceptuses, flunixin meglumine), and group-5 mares (8 mares, bicornuate twin conceptuses, flunixin meglumine), 1 conceptus was removed from the uterus via hysterotomy. All mares received progesterone prophylactically until day 100 of gestation or until the fetus died.
The 3 mares in group 1 delivered clinically normal, live foals. The mean prostaglandin F2α metabolite (pgfm) plasma concentration peaked at 180 ± 5.2 pg/ml during uterine manipulation and fetal palpation, then declined to baseline by 1 hour. Free placental fluid (group 2) undermined the chorioallantois ventrally and resulted in fetal death witin 3 hours after surgery. The mean pgfm plasma concentration peaked at 39 ± 4 pg/ml following injection of placental fluid. None of the remaining fetuses in the 7 mares with unicornuate twin conceptuses (groups 3 and 4) survived. Five mares with unicornuate twin conceptuses (group 5) delivered single viable foals. In another mare in group 5, the fetus was alive 4 days after surgery, when the mare was euthanatized for a fractured femur. The peak mean pgfm plasma concentration during hysterotomy in the mares not treated with flunixin meglumine(group 3) was 1,979 ± 27.36 pg/ml, and the highest peak mean pgfm plasma concentration in the flunixin meglumine-treated hysterotomized mares (groups 4 and 5) was 123 ± 4.8 pg/ml. Flunixin meglumine was at least 94% effective in inhibiting expected increases in pgfm plasma concentrations associated with hysterotomy.
Enhanced platelet reactivity in heartworm-infected dogs
Authors: Boudreaux Mary K. , Dillon Allen R. , Spano Joseph S. 
Published: February 2025

SUMMARY
Platelet number, mean platelet volume, and platelet function were evaluated in 34 clinically normal dogs and 28 heartworm-infected (hwi) dogs. Mean platelet numbers for dogs of the hwi group was not significantly lower than those for dogs of the control group (214,000 vs 254,000 cells/μl); however, 6 (21%) hwi dogs had platelet numbers < 150,000/μl, compared with only 2 (6%) heartworm-negative dogs. The mean platelet volume was not significantly different (7.8 vs 7.7 fl) between the 2 groups of dogs. Mean platelet aggregation responses to intermediate and low concentrations of collagen (3.0 and 1.5 μg) and to high, intermediate, and low concentrations of adp (25, 10, and 5 μM) were greater in dogs of the hwi group. Mean platelet 14C-serotonin release was also greater in hwi dogs in response to high concentration of adp (25 μM) and to intermediate concentration of collagen (3.0 μg).
Reference blood chemical values in ostriches (Struthio camelus)
Authors: Levy A. , Perelman B. , Waner T. , van Grevenbroek M. , van Creveld C. , Yagil R. 
Published: February 2025

SUMMARY
Reference blood chemical values were determined for 65 male and 61 female ostriches (Struthio camelus) 1 month to 72 months of age. Plasma values of glucose, total protein, triglycerides, cholesterol, uric acid, urea, bilirubin, creatinine, osmolality, electrolytes, and enzyme activity were determined. In general, differences in various values appeared mainly among age groups and less so between sexes. Older ostriches had lower plasma glucose values and enzyme activity than did younger ostriches. High plasma sodium and chloride concentrations in young ostriches correlated with high plasma osmolalities. Plasma calcium values were lower in laying ostriches. Uric acid concentrations were markedly higher than were urea concentrations in all ostriches.
Effect of Pasteurella haemolytica infection on the distribution of sulfadiazine and trimethoprim into tissue chambers implanted subcutaneously in cattle
Authors: Clarke Cyril R. , Short Charles R. , Corstvet Richard E. , Nobles Debbie 
Published: February 2025

SUMMARY
A study was designed to determine the effect of Pasteurella haemolytica infection on the rate and extent of penetration of sulfadiazine and trimethoprim into tissue chambers implanted sc in cattle. Thermoplastic tissue chambers were implanted sc in 6 calves. At 35 days after implantation, sulfadiazine (25 mg/kg of body weight) and trimethoprim (5 mgkg) were administered iv to 5 of the calves. Chamber fluid and blood samples were collected from each animal at various time intervals for 24 hours after administration. Ten days later, all chambers were inoculated with P haemolytica serotype 1. At 36 hours after inoculation, a second pharmacokinetic study was conducted, using sulfadiazine and trimethoprim. Drug doses and sampling schedules were identical to those used prior to inoculation. A histologic study of infected chamber tissue was conducted, using the calf not included in the pharmacokinetic studies. Disposition curves of antimicrobials in serum and chamber fluid were well described by 2-compartment and 1-compartment pharmacokinetic models, respectively. Inoculation of P haemolytica into tissue chambers was accompanied by marked changes in the composition of chamber fluid. Increased total protein and albumin concentrations, decreased pH, and disruption of chamber tissue vasculature were associated with a significant increase in the penetration of sulfadiazine and trimethoprim into infected tissue chambers, compared with that in noninfected chambers. This increased penetration was accompanied by increases in the apparent volume of distribution for sulfadiazine and trimethoprim.
Pharmacokinetics of ceftazidime given alone and in combination with probenecid to unweaned calves
Authors: Soback Stefan , Ziv Gideon 
Published: February 2025

SUMMARY
Ceftazidime pharmacokinetic values were studied in unweaned calves given the antibiotic alone or in combination with probenecid. Ceftazidime was administered iv to 9 calves at a dosage of 10 mg/kg of body weight and im (10 mg/kg) to 8 calves, to 7 calves (10 mg/kg plus probenecid [40 mg/kg]), and to 9 calves (10 mg/kg plus probenecid [80 mg/kg]). Serum concentration-vs-time data were analyzed, using noncompartmental methods based on statistical moment theory. The data for iv ceftazidime administration also were fitted by use of a linear, open 2-compartment model.
The mean (± sd) terminal half-life was 138.7 ± 23.6 minutes and 126.3 ± 10.5 minutes after iv and im administrations, respectively. The mean residence time was 167.3 ± 21.1 minutes and 201.4 ± 16.8 minutes after iv and im administrations, respectively. Coadministration of probenecid did not affect the terminal half-life or mean residence time values. The total body clearance was 1.75 ± 0.26 ml/min/kg, and the volume of distribution at steady state was 0.294 ± 0.064 L/kg. The estimated mean absorption time was 34.1 minutes.
There were no significant differences between the mean residence time calculated by statistical moment theory or by compartmental analysis, indicating central compartment output of ceftazidime.
The 90% minimal inhibitory concentration values of ceftazidime determined for Escherichia coli, Salmonella spp, Pasteurella multocida, and P haemolytica isolates ranged from < 0.01 to 0.1 μg/ml.
Effect of food deprivation on d-xylose absorption test results in mares
Authors: Freeman David E. , Ferrante Pamela L. , Kronfeld David S. , Chalupa William 
Published: February 2025

SUMMARY
A d-xylose absorption test was conducted on 4 healthy mares deprived of food for 12, 36, 72, and 96 hours before the test, with a 13- to 15-day adjustment period between each test. Maximal plasma concentrations after 72 and 96 hours of food deprivation were approximately 36% lower than those obtained after the 12- and 36-hour periods (P = 0.0001). Absorption curves were flatter and the decrease in plasma concentration was slower after the 72- and 96-hour periods of food deprivation. The rate of d-xylose absorption (P = 0.0108) and the initial rate of urinary excretion (P = 0.0117) were slower at 72 and 96 hours. Gastric emptying appeared to be progressively delayed with food deprivation, as evident by the delay in peak d-xylose excretion in urine (P = 0.0268). Areas under the plasma concentration-time curves and quantitites of d-xylose excreted in urine were similar for all periods of food deprivation, evidence that the same amounts of d-xylose were absorbed, despite changes in the plasma curve. A 15-hour collection period was sufficient to recover all d-xylose excreted in the urine, and during all periods 9.8 ± 0.6% (mean ± sem) of the oral dose was eliminated in the urine.
Detection of intracellular canine distemper virus antigen in mink inoculated with an attenuated or a virulent strain of canine distemper virus
Authors: Blixenkrone-Møller Merete 
Published: February 2025

SUMMARY
Using an indirect immunofluorescence technique, the distribution of viral antigen in various tissues and blood mononuclear leukocytes was studied in wild mink, either vaccinated with an attenuated vaccine strain of canine distemper virus (cdv) or experimentally inoculated with the virulent Snyder-Hill strain of cdv. Viral antigen was detected in cells of the lymphoid system 6 to 12 days after vaccination. From 2 to 3 days after inoculation with the virulent strain, cdv antigen was demonstrated in cells of the lymphoid system and, during the incubation period, the antigen had spread to the epithelia and brain at days 6 and 12, respectively. In clinical cases of acute fatal canine distemper, the viral antigen was detected in a wide variety of tissues, including the cells of the lymphoid system, epithelial cells of skin, mucous membranes, lung, kidney, and cells of the cns. The diagnostic importance of cdv antigen detection is discussed on the basis of these findings.
Large intestinal capacity, retention times, and turnover rates of particulate ingesta associated with extensive large-colon resection in horses
Authors: Bertone Alicia L. , VanSoest Peter J. , Johnson Donald , Ralston Sarah L. , Stashak Ted S. 
Published: February 2025

SUMMARY
Fecal excretion of a particulate marker, ytterbium (Yb), was evaluated in 9 horses before surgery and 3 weeks, 3 months, and 6 months (4 trials) after sham-operation (group 1; n = 3) or extensive large colon resection (group 2; n = 6). Fecal excretion curves of total Yb excretion, loge Yb excretion, % Yb excretion, loge % Yb excretion, and cumulative % Yb excretion were evaluated, and kinetic analysis was performed on the loge Yb excretion curves to detect mixing pools and to calculate the fractional rate of particulate passage, turnover rate, and pool size. Calculations were performed to determined transit time, mean overall retention time, adjusted mean retention time, peak time, and disappearance time. Values were statistically analyzed to determine differences between groups and among trials (P < 0.05).
Group-2 horses had significantly shorter transit, peak, and mean overall retention times, compared with preoperative values and with values for group-1 horses. Two mixing pools were identified: a slower emptying pool of 5.7% hour-1 (k1) and a faster emptying pool of 12.3% hour-1(k2). The rate of passage from the first pool (k1) was not altered by colon resection, and was interpreted as being most influenced by the cecum. In further support of this interpretation, the capacity of the k1 pool approximated the capacity of the cecum (17 L). The capacity of the k1 pool significantly expanded by 6 months in the resected horses. The rate of passage from the second pool (k2) significantly increased initially after colon resection (3 weeks and 3 months), but returned to preoperative values by 6 months. This pool was affected by colon resection, and was therefore interpreted as being influenced by a portion of the colon. Despite these changes in rate of passage and capacity of the mixing pools, on all the trials, colon resection decreased intestinal transit time and overall mean retention time because of a decrease in the total large intestinal length or capacity. This decrease in particulate matter retention and transit time may partially or totally explain the decrease in fiber digestion reported in horses with extensive large colon resection.
Direct effects of Pasteurella haemolytica lipopolysaccharide on bovine pulmonary endothelial cells in vitro
Authors: Paulsen Daniel B. , Mosier Derek A. , Clinkenbeard Kenneth D. , Confer Anthony W. 
Published: February 2025

SUMMARY
Bovine pulmonary artery cells in cell culture were exposed to lipopolysaccharide (lps) purified from Pasteurella haemolytica serotype Al. This resulted in severe membrane damage, which caused a time- and dose-dependent release of lactate dehydrogenase that was first detected 4 hours after exposure and reached a maximal mean release of 67% after 24 hours of exposure to 1 μg of lps/ml. Mean release of 51chromium followed by a similar pattern and reached a maximum of 61% following 24 hours of exposure to 10 μg of lps/ml. Morphologically, endothelial cells responded to lps by marked cell membrane retraction, the formation of numerous cytoplasmic blebs, and ruffling of the cell membrane. Subsequently, the cells became round and detached. Cell detachment reached a mean of 95% following 8 hours of exposure to 1 μg of lps/ml. These studies demonstrated that P haemolytica lps is capable of causing direct damage to bovine pulmonary arterial endothelial cells, which may be important in the pathogenesis of bovine pneumonic pasteurellosis.
Rapid detection of Streptococcus suis serotype 2 in weaned pigs
Authors: Moreau Alain , Higgins Robert , Bigras-Poulin Michel , Nadeau Marie 
Published: February 2025

SUMMARY
A survey to detect Streptococcus suis serotype 2 in 1,716 weaned pigs was done in Quebec. Forty-nine sow herds surve included in this survey: in 26 herds, S suis serotype 2 had been isolated during the preceding 12 months and in 23 herds (control), the organism had not been detected during a previous study. Swab specimens of the nasal cavity and tonsils of pigs were obtained for bacteriologic culture, and S suis serotype 2 was easily detected by the use of brain-heart infusion agar containing a Streptococcus-selective supplement and 5% goat antiserum raised against S suis serotype 2. After measurement of the diameter of the precipitation zone of 539 isolates, a slide agglutination test was performed to identify the S suis serotype 2 isolates. The mean precipitation zone diameter obtained for group S suis serotype 2 was larger (P < 0.001) than that for the group designated as “others.” With slide agglutination test results as reference and on the basis of discriminant analysis to simulate detection of S suis serotype 2, 93.1% of all isolates were correctly classified, using the precipitation zone diameter as unique classification criterion. Relative specificity was 94.5% and relative sensitivity was 88.7%.Use of the precipitation zone diameter on a quantitative basis led to the proposal of a simple and reliable technique to screen swine herds for S suis serotype 2 in weaned pigs. Nasal and tonsillar swab specimens were obtained and analyzed concurrently for S suis serotype 2. The organism was found in both sites in only 20.4% of 103 carrier pigs. Nasal and tonsillar specimens yielded 55.3 and 65%, respectively, of all S suis serotype 2 isolates. Statistically significant difference was not observed between the numbers of S suis serotype 2 isolated from each site. Both sites permitted the recovery of S suis serotype 2 isolates; it was advantageous to use nasal and tonsillar swab specimens to determine the most reliable evaluation of S suis sterotype-2 carrier status in weaned pigs.
Characterization of the plasmids of Moraxella bovis
Authors: Wilt G. R. , Wu G. , Bird R. Curtis 
Published: February 2025

SUMMARY
Restriction endonuclease digestions were performed on plasmids purified from Moraxella bovis isolates GRS, Newport, and IBH64. It was determined from single and double digestions of plasmid dna that GRS and Newport isolates carried 3 large plasmids having molecular sizes of 43.8, 41.3, and 32.8 kilobases (kb). Digestion of the 3 large plasmids and restriction endonucleases Hae III, HindIII, Nde I, and Ava I strongly indicated that these isolates shared structurally identical large plasmids. Timed single digestions with Ava I revealed that the IBH64 isolate carried 2 large plasmids having molecular sizes of 45 and 32.8 kb. The 32.8-kb plasmid was the only large plasmid that appeared to be shared by all 3 M bovis isolates. Two isolates, Newport and IBH64, carried small plasmids in addition to the large plasmids. Restriction maps were constructed for the 43.8-, 41.3-, and 32.8-kb plasmids.
Changes in articular cartilage after intra-articular injections of methylprednisolone acetate in horses
Authors: Chunekamrai Siraya , Krook Lennart P. , Lust George , Maylin George A. 
Published: February 2025

SUMMARY
Eight mature horses with no prior signs of joint disease or history of intra-articular therapy were treated with 8 weekly intra-articular injections of methylprednisolone acetate. Treatments were given at a dose of 120 mg/joint into the right radiocarpal and intercarpal joints, with the left joints as untreated controls. Articular cartilage samples were obtained at necropsy 1, 4, and 8 weeks after the last injection.
Compared with controls, cartilage from injected joints had a loss of hematoxylin basophilia and decreased intensity of staining in safranin O fast green dye. Chondrocyte necrosis and hypocellularity were observed in all sample of cartilage from treated joints. Proteoglycan content and its rate of synthesis were reduced. There was a progressive loss of proteoglycan content, whereas proteoglycan synthesis increased somewhat 4 and 8 weeks after treatment. Collagen content was unchanged, but its rate of synthesis was markedly inhibited. Collagen synthesis did not recover, but remained decreased at 5 to 15% of the values from untreated cartilage. Water percentage was increased, but fibronectin content was not significantly different.
A single injection of methylprednisolone acetate was also given into the right metacarpophalangeal joints of 3 of the 8 horses in this group, with the left joints serving as untreated controls. Sixteen weeks after the treatment, cartilage of the treated joints had a loss of histochemical staining and proteoglycan content was reduced to 50% of control values. The mean rate of proteoglycan synthesis and mean fibronectin content were increased, but the differences were not statistically significant (P > 0.05). Other variables were essentially unchanged. For control studies, the right carpal joints of 2 additional horses were injected with the drug suspension vehicle. All measurements, compared with those of samples from untreated joints, were unchanged.
On the basis of our findings, we concluded that the effects on cartilage of intraarticular injections of methylprednisolone acetate were not ameliorated at 8 weeks after 8 weekly injections or 16 weeks after a single injection. Cartilage remained biochemically and metabolically impaired.