bluuebunny/crossref_metadata_2025 huggingface dataset:
Increase of serum lipid-associated sialic acid concentration in dogs with neoplasms
Authors: Poli A. , Arispici M. , Camillo F. , Corazza M.
Published: February 2025

Serum concentrations of lipid-associated sialic acid (lasa) were determined in sera obtained from 26 apparently healthy dogs (group 1), 56 dogs with nonneoplastic disorders (group 2), and 100 dogs with neoplasms (benign [group 3], malignant [group 4]), using a simple, reliable, rapid spectrophotometric procedure.

The lasa concentrations were significantly increased (P < 0.01) in group 4 dogs (malignant neoplasms) when compared with those in dogs from groups 1, 2, and 3.

The sensitivity of the test was between 71.5% and 100%, and specificity was 92.3% for group 1, 67.8% for group 2, and 80.6% for group 3.

A preliminary study concerning variations of serum lasa values as a marker after surgical treatment of tumor showed a good correlation between effectiveness of therapy and serum lasa concentrations.
Microscopic alterations in jejunal epithelium of 3-week-old pigs induced by pig-specific, mouse-negative, heat-stable Escherichia coli enterotoxin
Authors: Whipp Shannon C. , Moseley Steve L. , Moon Harley W.
Published: February 2025

The objective of this study was to determine whether exposure of swine jejunum to crude culture filtrates containing Escherichia coli pig-specific, mouse-negative, heat-stable enterotoxin (STb) induces structural alterations in the jejunal mucosa of pigs. Two ligated intestinal loops in each of twelve 3-week-old pigs were exposed for 2 hours to sterile E coli culture filtrates from each of the following strains: 431 (STa-producing), 1261 (STa and STb-producing), and 1790 (STb-producing); recombinant strain HB101-pRAS-1 (STb-producing); the nontoxigenic K-12 variant HB101; or trypticase soy broth. Formalin-fixed sections from these loops were examined for sloughed cells around villi, and a lesion score was determined, indicating a change in villous epithelium from columnar to cuboidal or squamous cell types or to discontinuous epithelium. Villous lengths and crypt depths also were determined. For loops exposed to culture filtrates containing STa and STb or containing only STb, lesion scores and numbers of sloughed cells were greater (P < 0.05) and villous length was shorter (P < 0.01) than in loops not exposed to toxin. For loops exposed to culture filtrates containing STa, lesion scores, villus lengths, and numbers of sloughed cells were not different from those of loops not exposed to toxin. Therefore, exposure of swine jejunum to STb induced structural alterations in intestinal mucosa (ie, loss of villous absorptive cells and partial atrophy of villi) that were consistent with those causing compromised absorptive capacity.
Comparison of porous titanium-surfaced and standard smooth-surfaced bone plates and screws in an unstable fracture model in dogs
Authors: Orton E. Christopher , Polher Ortrun , Shenk Robert , Hohn R. Bruce
Published: February 2025

Bilateral midshaft femoral osteotomies were fixed with a 3-mm fracture gap in 6 dogs. In each dog, one femur was fixed with a porous titanium-surfaced bone plate and screws, whereas the opposite femur was fixed with a standard smooth-surfaced bone plate and screws. The mean removal torque for porous titanium-surfaced screws (32.3 kg·cm) was significantly (P < 0.01) greater than the mean removal torque for standard screws (4.4 kg·cm). Osseous tissue ingrowth into the surface of porous titanium-surfaced screws was verified by histologic examination of the bone-screw interface.

Radiographic and histologic examinations of the osteotomy gaps showed accelerated primary gap healing in osteotomies fixed with porous titanium-coated implants, compared with slower callus healing seen in osteotomies fixed with standard smooth-surfaced implants.
Isolation of Leptospira interrogans serovar bratislava from sows in Iowa
Authors: Ellis William A. , Thiermann Alex B.
Published: February 2025

Leptospira interrogans serovar bratislava was recovered from 2 of 10 sows examined from an Iowa slaughterhouse. Isolations were made from the kidney and genital tract of each sow. Serovar bratislava is not included in vaccines because it has not been previously isolated in the United States.
Cytotoxicity of bovine lymphocytes after treatment with lymphokines
Authors: Campos Manuel , Rossi Charles R.
Published: February 2025

Cytotoxic lymphocytes were generated from bovine peripheral blood mononuclear leukocytes after in vitro stimulation with lymphokines that contained interleukin-2. Lymphokine-stimulated cultures were cytotoxic to K562 cells (human natural killer [nk] targets) and YAC-1 cells (mouse nk targets), but not to HSB-2 cells (human nk targets) in a 4-hour, 51Cr-release assay. Cells generated after lymphokine activation also mediated antibodydependent cellular cytotoxicity to HSB-2 cells. Appearance of effector cells as a function of time in culture, method of stimulation, and cold target competition experiments strongly indicated that direct cytotoxicity and antibodydependent cellular cytotoxicity may have been mediated by the same cell. Cells generated by similar conditions were able to mediate cytotoxicity against infectious bovine rhinotracheitis virus-infected target cells, especially in an 18-hour assay.
Efficacy of a morantel sustained-release bolus for the control of gastrointestinal nematodes in Florida dairy heifers
Authors: Bradley R. E. , Bliss D. H. , Newby T. J.
Published: February 2025

The effectiveness of a morantel sustained-release bolus (msrb) in controlling gastrointestinal nematode infections was determined in 70 Holstein heifer calves with no prior grazing experience. Calves were allotted to 2 treatment groups and were maintained in Florida during the grazing season on divided pastures of equal area. One msrb was administered to each calf in 1 group at the time of turnout onto spring pasture, whereas calves in the other group remained as nonmedicated controls. By the end of the grazing season, treatment resulted in significantly (P < 0.05) lower worm burdens and significantly improved weight gains. The msrb-treated calves were able to reach breeding weight 2 to 4 weeks earlier than did nonmedicated calves.
Detection of transmissible gastroenteritis coronavirus antigens by a sandwich enzyme-linked immunosorbent assay technique
Authors: Bernard S. , Lantier I. , Laude H. , Aynaud J. M.
Published: February 2025

A new sandwich enzyme-linked immunosorbent assay, using monoclonal and polyclonal antibodies, was developed to detect transmissible gastroenteritis virus antigens from cell culture and from intestinal wash or feces obtained from experimentally infected pigs. This technique was shown to be suitable for the detection of virulent field strain unadapted to cell culture. Cross reactions had not been observed with other enteric pathogens, rotavirus, porcine epizootic diarrhea virus, and Escherichia coli.
Increase of serum γ-glutamyltransferase in neonatal Standardbred foals
Authors: Patterson William H. , Brown Christopher M.
Published: February 2025

Serial blood samples were obtained from 16 Standardbred foals from time of birth to postpartum day 28. Sera were obtained and analyzed for γ-glutamyltransferase (ggt), aspartate transaminase, and immunoglobulin (Ig) G. Presuckle colostrum from the respective mares of these foals was analyzed for ggt activity.

Mean serum aspartate transaminase activities were significantly increased above presuckle values by postpartum hour 48 (P < 0.01) and increased gradually over the first 14 days. Mean serum IgG concentrations were significantly greater than presuckle values by 5 hours after foals first suckled (P < 0.01) and remained significantly increased during the 28-day sampling period.

Serum ggt activity did not differ significantly over the period sampled. The sd were large, since there was a large degree of interindividual variation. Serum ggt activity in the foals was significantly increased over that in the mares throughout the period of the study. The profile of serum ggt activity over time in each foal did not show a pattern of change. There was no postsuckle increase in serum ggt activity nor a correlation between serum ggt activities and IgG concentrations at 24 hours after foals first suckled. Evidence was not obtained to support a colostric source of ggt involved in the increase of serum ggt activity in foals. Serum ggt activity seems to be increased in foals due to endogenous sources.
Effects of eight weeks of physical conditioning on atherosclerotic plaque in swine
Authors: van Oort Gijs , Gross David R. , Spiekerman A. M.
Published: February 2025

Effects of individually prescribed exercise on the regression or interference with deposition of atherosclerotic plaque were studied. Twenty miniature swine allotted, by litter, to a control-diet group (groups CE and CS) and an atherogenic diet group (groups AE and AS). All pigs were subjected to injury (balloon catheter) of the aortic endothelium. They were fed for 8 weeks and after an initial graded exercise test was done, then each group was suballotted to an exercising group (groups CE and AE) or a sedentary group (groups CS and AS). Groups CE and AE (exercised) were given 8 weeks of training. Groups CS and AS (sedentary) were sham exercised during this period. A second graded exercise test was administered to the swine (all groups) before they were euthanatized. Aortas were analyzed for the percentage of area involved and for atherosclerotic plaque density. Samples of blood from the swine after they were fasted were obtained before the start of the project (base line) and once every 2 weeks thereafter. These were analyzed for triglycerides, high- and low-density lipoprotein, and total cholesterol concentration. Comparison of results of blood lipid analyses from weeks 1, 9, and 15 did not show significant differences within diet groups between exercise and sedentary. Significant differences at weeks 9 and 15 were observed between diet groups (ie, the pigs fed the atherosclerotic diet had higher blood lipids). Plaque formation was not found in the pigs fed the control diet (groups CE and CS). Plaque formation was evident in all pigs fed the atherosclerotic diet (groups AE and AS) with no significant differences between exercised and sedentary groups. We conclude that 8 weeks of exercise conditioning has no effect on deposition or regression of atherosclerotic plaque in miniature swine subjected to marked hyperlipemia and endothelial damage.
Clinical and hematologic variables in ponies with experimentally induced equine ehrlichial colitis (Potomac horse fever)
Authors: Ziemer Ellen L. , Whitlock Robert H. , Palmer Jonathan E. , Spencer Pamela A.
Published: February 2025

The clinical and hematologic variables of 10 ponies with experimentally induced equine ehrlichial colitis (eec; syn: Potomac horse fever) were studied for a 30-day period (6 ponies) or until death (4 ponies). The earliest clinical sign indicative of eec was fever (rectal temperature exceeding 39 C). All ponies became depressed (cns) at various times during the disease, and 90% of the ponies developed diarrhea between 9 and 15 days after infection was induced. The most significant hematologic change was an increase in plasma protein concentration after the onset of fever (P < 0.05). The pcv in all ponies became increased above base line during the diarrheic phase of eec. Forty percent of the ponies developed anemia (pcv ≤ 23%) during the study. White blood cell counts were highly variable, with 80% of the ponies developing leukopenia (wbc < 5,000/μl) during the illness and 60% of ponies developing leukocytosis (wbc > 14,000/μl) after leukopenia was observed. Differential wbc changes varied widely and included neutropenia with a left shift, lymphopenia, and eosinopenia. Serial thrombocyte counts, which were done for only 1 pony, identified the development of marked thrombocytopenia. Some hematologic changes in ponies with eec were similar to those reported in canine monocytic and equine granulocytic ehrlichioses. These data are discussed in the context of the pathogenesis and differential diagnosis of eec.
Characterization of feline T and B cells
Authors: Kuramochi T. , Takeishi M. , Ishida T. , Kato K. , Ishida M.
Published: February 2025

Feline peripheral-blood lymphocyte populations (n = 22) were examined for the following markers: rosette formation with guinea pig erythrocytes (gpe-t cells), rosette formation with human rbc (hrbc-t cells), rosette formation with sheep rbc, mixed rosette formation with gpe-T cells and hrbc-t cells (total T cells), erythrocyte antibody-complement rosettes, and surface immunoglobulin. An average of 28% ± 7% (range, 16% to 39%) of the feline lymphocytes formed rosettes with gpe-t cells, and 27% ± 17c (range, 11% to 36%), with hrbc-t cells. An average of 57% ± 97r (range, 33% to 757c) of the lymphocytes formed mixed rosettes. The erythrocyte antibody-complement rosette-forming cells and surface immunoglobulin-bearing cells were found in peripheral blood lymphocytes (10% ± 6% and 24% ± 8%, respectively).

The murine monoclonal antibodies OKT 11 and HuLy-m1, specific for a framework determinant of human E-rosette receptor antigens, cross-reacted with feline cell membrane molecules recognizing a bimolecular complex (45,000 to 50,000 daltons) similar to that described in persons. We investigated the distribution of these E-rosette receptor-like antigens on feline lymphocytes. By complement-mediated lymphocytotoxicity, about 30% of the feline lymphocytes expressed the antigens. When lymphocytes were treated with HuLy-m1 antibody, spontaneous rosette formation with hrbc-t cells was significantly inhibited.
Abortion in sows experimentally infected with African swine fever virus: Pathogenesis studies
Authors: Schlafer Donald H. , Mebus Charles A.
Published: February 2025

Thirteen sows that were 38 to 92 days pregnant were experimentally infected with an African swine fever (asf) virus strain of low virulence (Dominican Republic isolate). Seven of 11 sows that were not killed had aborted. The pathogenesis of the abortions was studied, using virus isolation, tissue immunofluoresence, and histopathologic techniques.

African swine fever virus was recovered from 179 of 1,329 (13.5%) fetal tissues tested. The 3 fetal tissues most frequently yielding virus were the fetal placenta, amniotic fluid, and fetal heart blood. Virus was not recovered from fetal tissues obtained from 2 of the aborting sows.

Direct immunofluorescent microscopy for asf viral antigen was done on approximately 1,175 fetal tissues. Although brightly fluorescing cells were common in maternal tissues, specific immunofluorescence was present in only placental tissues from 2 sows.

Microscopic lesions in fetal tissues were inconsistent and included mild focal placentitis, mild heptic degeneration and necrosis, and mild interstitial pneumonia. These changes were not considered to be sufficiently specific to have diagnostic significance.

In marked contrast to these changes in the fetal tissues, maternal tissues had high titers of virus, with marked necrosis of lymphoid tissues, and contained many cells with asf viral antigen. We conclude that specific diagnosis of abortion resulting from asf infection should, therefore, be based on examination of maternal tissues, rather than fetal tissues. The pregnancy failure seems to result from the effects of the virus infection on the dam more so than from direct viral damage to the placenta or fetus.
Shedding of enteric Coronavirus in adult cattle
Authors: Collins James K. , Riegel Cynthia A. , Olson Jerry D. , Fountain Angela
Published: February 2025

Electron microscopic examination of fecal specimens from adult dairy cows indicated seasonal Coronavirus shedding. Fifty-two cows from a 300 cow herd were monitored for shedding of coronavirus. Approximately 50% to 60% of the cows monitored shed coronavirus during the winter months (November to March) of the first year of the study. During 2 subsequent years of monitoring the same cows, 20% to 30% of the cows shed coronavirus during the winter months. Virus shedding was not detected during the summer months (July to September). Half of the cows monitored were vaccinated with a modified-live rotavirus-coronavirus-Escherichia coli combination vaccine; however, vaccination did not influence seasonal shedding of coronavirus, as compared with shedding in the nonvaccinated cows. In nonvaccinated cows that calved in the winter months, the incidence of coronavirus shedding increased from 20% to 30% during the last 2 months of gestation to 65% to 70% at parturition. In vaccinated cows, the incidence of shedding did not increase at parturition.
Isolation of leptospires from nephritic kidneys of beef cattle at slaughter
Authors: Grégoire Nicole , Higgins Robert , Robinson Yves
Published: February 2025

Of 955 beef cattle slaughtered at an abattoir in Quebec from May to August 1985, 122 (13%) had lesions of focal interstitial nephritis. Nephritic kidneys were collected for leptospiral culture, and matching blood samples were examined serologically. Leptospires were isolated from the kidneys of 35 (29%) cattle. Antibodies to Leptospira interrogans serovar hardjo were found in 29 (24%) cattle and to pomona in 13 (10%).
Radiolabeling of equine platelets in plasma with 111In-(2-mercaptopyridine-N-oxide) and their in vivo survival
Authors: Coyne Cody P. , Kelly Andrew B. , Hornof William J. , O'Brien Timothy R. , Philp Mary Sue , Lamb James F.
Published: February 2025

A method is presented for the in vitro isolation and radiolabeling of equine platelets with the isotope indium 111 (111In: half-life = 2.8 days, gamma = 173 keV, 89%; 247 keV, 94%). The technique described involves complexing 111In with the lipid-soluble chelating agent, 2-mercaptopyridine-N-oxide (mere), in an aqueous medium. inIn-merc platelet-labeling efficiencies in autologous plasma pretreated with or without ferric citrate reagent were 82 ± 7% and 24 ± 12%, respectively. Mean intravascular survivals of 111In-merc-radiolabeled platelets in 8 healthy horses according to simple linear, exponential, mean, weighted-mean residual sum of squares analysis, and multiple-hit model were 5.5 ± 0.49, 3.5 ± 0.53, 4.5 ± 0.18, 4.3 ± 0.65, and 3.6 ± 0.97 days, respectively.
Esophageal manometry in horses, cows, and sheep during deglutition
Authors: Clark E. Susan , Morris Debra Deem , Whitlock Robert H.
Published: February 2025

Esophageal pressure events during deglutition were evaluated in healthy adult animals (6 horses, 6 cattle, and 5 sheep), using a 3-side hole catheter assembly perfused with water by use of a hydraulic-capillary infusion system. The peak postdeglutition pressure, contraction time, and contraction length were determined for the cranial and caudal esophageal sphincter regions and for each functionally different region within the body of the esophagus. The percentage of deglutitions in which relaxation developed at the sphincter regions and the propagation speed (velocity at which pressure waves traversed the esophagus) for the regions within the body of the esophagus also were determined.

Mean (± sem) resting pressures within the cranial and caudal esophageal sphincter regions in the horse were 84.8 ± 4.39 and 12.7 ± 0.61 mm of Hg, respectively, with postdeglutition peaks of 208.0 ± 4.78 and 100.0 ± 1.06 mm of Hg, respectively. Peak postdeglutition pressure was 92.3 ± 1.59 mm of Hg in the cranial two thirds of the esophageal body and 100.9 ± 1.31 mm of Hg in the caudal third.

Mean resting pressure of the cranial esophageal sphincter region in the cow was 82.0 ± 7.81 mm of Hg, whereas that of the caudal esophageal sphincter region was 20.5 ± 0.36 mm of Hg. The peak postdeglutition pressures for the cranial esophageal sphincter region, proximal portion of the esophageal body, caudal portion of the esophageal body, and caudal esophageal sphincter region in the bovine esophagus were 238.1 ± 2.93, 105.4 ± 1.97, 114.5 ± 1.49, and 112.0 ± 1.20 mm of Hg, respectively.

Mean resting pressures in the cranial and caudal esophageal sphincter regions in sheep were 36.0 ± 4.62 and 10.4 ± 0.21 mm of Hg, respectively. Peak postdeglutition pressures in the cranial and caudal esophageal sphincter regions were 105.7 ± 1.55 and 58.3 ± 0.87 mm of Hg, respectively. Mean peak postdeglutition pressures in the distal, middle, and proximal thirds of the body of the esophagus were 46.5 ± 1.32, 50.0 ± 1.52, and 44.8 ± 1.43 mm of Hg, respectively.
Renal ultrasonography in healthy cats
Authors: Walter P. A. , Johnston G. R. , Feeney D. A. , O'Brien T. D.
Published: February 2025

Serial ultrasonographic examinations were performed on the kidneys of 10 healthy cats during normal hydration and after administration of contrast medium. Differences in the appearance of anatomic structures or in the echo intensity were not detected between kidneys during normal hydration and after contrast medium administration. The appearance of scanning images was influenced by mode, frequency, and focal range of the transducer, topography and mobility of the kidneys, and adequate sound conduction.
Hormonal changes in sows after induced porcine parvovirus infection in early pregnancy
Authors: Meyers Patrick J. , Liptrap Robert M. , Miller Richard B. , Thorsen Jan
Published: February 2025

Hormonal changes, lesions, and virus isolation studies were determined in sows after uterine artery inoculation with porcine parvovirus ([ppv], strain NADL-8) in early pregnancy. Two sows were given ppv on days 14 or 16 and were euthanatized and necropsied on day 35 after twice daily plasma collection for hormone measurement. Parvovirus was given to 4 sows on day 14 and to 4 sows on day 21 with 5 times daily plasma samples collected for 1 week. Sows were examined on days 21 and 28, respectively. Four control sows in each group on days 14 and 21 were given a placebo injection and were similarly studied. All embryos in all but 1 sow given ppv were in various stages of resorption at necropsy. Normal embryos were present in all control sows.

Estrone sulfate values increased logarithmically, progesterone values remained stable, and concentrations of 13, 14-dihydro-15-keto-prostaglandin (pg) F2α (pgfm), a pgf2α metabolite, were < 200 ng/ml for sows given a placebo. In contrast, sows with resorbing embryos did not have an increase in estrone sulfate values. A decrease in plasma progesterone values occurred in 9 of 10 sows inoculated with ppv; this decrease was accompanied by ≥ 1 marked increase in pgfm concentrations.

Quantitative assessment of the uterus revealed significantly greater cytoplasmic density in endometrial and glandular cell (P < 0.01), a greater glandular epithelium height (P < 0.05), and twice the number of glands (P < 0.05) in control sows, compared with values in sows inoculated with ppv. Virus isolation studies were positive for embryos of inoculated sows, but were consistently negative for those of control sows. Porcine parvovirus was recovered from 6 of 8 sows inoculated with ppv, but not from sows injected with a placebo. The importance of the hormone changes are interpreted in the light of pathologic alterations.
Evaluation of a simplified blood pepsinogen assay
Authors: Berghen P. , Dorny P. , Vercruysse J.
Published: February 2025

Blood pepsinogen concentrations in cattle were determined, using a simple, direct method based on the hydrolysing effect of serum on buffered bovine albumin substrate (2 g/dl). The amount of tyrosine released was measured at 680 nm, using the Folin and Ciocalteu's colorimetric method. To ensure an optimal digestion in vitro, a glycine-hydrochloric acid buffer (0.1M) was evaluated at various pH. Serum samples with medium (2,591 mU of tyrosine) and high (6,222 mU of tyrosine) pepsinogen concentrations had the highest proteolytic activity at pH 2.5. Substituting albumin by hemoglobin substrate resulted in almost double the amount of hydrolyzed products. For preparation of standard pepsin or pepsinogen curves, the incorporation of serum (activated or inactivated) diminished the tyrosine released to only half the amount obtained without serum. The use of serum or plasma did not significantly affect the results of the test, nor did prolonged storage at −70 C result in marked differences in the results.
Pharmacokinetics of diacetoxyscirpenol in cattle and swine: Effects of halothane
Authors: Coppock R. W. , Swanson S. P. , Gelberg H. B. , Koritz G. D. , Buck W. B. , Hoffmann W. E.
Published: February 2025

In swine and cattle given 0, 0.1, or 0.5 and 0, 0.5 mg of diacetoxyscirpenol (das)/kg of body weight, iv, respectively; das had a large volume of distribution and total body clearance. The shortness of the interval between halothane and das exposures significantly (P >; 0.05) decreased das biotransformation. Urinary excretion of das as a parent compound was not an important route of elimination. In swine and cattle, das was transformed by sequential deacetylation to monoacetoxyscirpenol and scirpentriol.
Changes in small intestinal morphology and flora associated with decreased energy digestibility in calves with naturally occurring diarrhea
Authors: Youanes Youanes D. , Herdt Thomas H.
Published: February 2025

Fecal composition was studied in 5 healthy Holstein calves and in 10 with naturally occurring diarrhea. The calves were between 5 and 21 days of age. The mean fecal contents of fat, lactate, and acetate were higher in the calves with diarrhea than in the healthy calves (P < 0.01). On the basis of calculated values, the mean caloric uptake from milk was decreased by 31% in diarrheal calves, compared with that in controls. At least half of the diarrheal calves were calculated to be in negative energy balance during the fecal collection period. This occurred in spite of consumption of a diet sufficient to provide more than enough energy for maintenance in healthy calves.

The mean values for villous lengths were decreased at all portions of the small intestine in the calves with diarrhea, compared with those values in healthy calves. Similarly, the mean intestinal epithelial lactase activities were decreased in the calves with diarrhea, compared with those activities in healthy calves. Villous length was negatively correlated with fecal lactate content (r = −0.88 in the duodenum, r = −0.66 in the jejunum, and r = −0.80 in the ileum), but not with fecal fat content. Intestinal lactase activity in the cranial portion of the intestine tended to be negatively correlated with fecal lactate content.

The mean concentration of total viable bacteria in the ileum was 1,000-fold higher in the diarrheal calves than in the healthy calves (109 vs 106/5-cm intestinal segment; P < 0.001), whereas the mean concentrations of total viable bacteria in the duodenum and jejunum of healthy and diarrheal calves were approximately the same. The concentration of coliform organisms was higher in the principal calves than that in the healthy calves in all 3 small intestinal sections (P < 0.05). The concentration of coliform organisms in the duodenum was positively correlated with fecal lactate content (r = 0.77, P < 0.05).

It was concluded that fat and carbohydrate malabsorption occurs frequently in calves > 5 days of age that have diarrhea. The accompanying decrease in dietary energy digestibility was substantial and may contribute to the death of these calves, particularly in cold weather. Small intestinal epithelial damage seemed to cause carbohydrate malabsorption, but the mechanism responsible for fat malabsorption was not apparent. Small intestinal bacterial overgrowth with a predominance of coliform organisms is common in calves with diarrhea and malabsorption, and its occurrence is probably independent of the inciting cause.
Acid-base and electrolyte balance in dairy heifers fed forage and concentrate rations: Effects of sodium bicarbonate
Authors: Roby K. A. W. , Chalupa W. , Orsini J. A. , Elser A. H. , Kronfeld D. S.
Published: February 2025

SUMMARY AND CONCLUSIONS

Eight Holstein heifers were fed diets of alfalfa hay, corn silage, or finely ground corn grain with or without NaHC03 in a rotating experimental design. Acid-base status and renal excretion of electrolytes were evaluated during shortterm (1 and 5 day) and long-term (24 day) feeding trials. Heifers fed alfalfa hay had a greater metabolic buffering capacity than did heifers fed corn silage. Heifers fed grain had lower blood pH and bicarbonate values than did those fed the forage diets. The most pronounced effects of grain-feeding were aciduria and phosphaturia. Aciduria did not occur when NaHCO3 was added to the grain at 2% of the ration on a dry matter basis. Grain-fed heifers had significantly (P < 0.05) lower blood and urine pH and bicarbonate values, and excreted significantly more calcium, phosphorus, and magnesium in the urine than did those fed grain plus NaHC03. Sodium bicarbonate, as a 2% dietary supplement, counteracted many effects of high-grain diets.
In vitro viral expression as a criterion for development of control procedures for enzootic bovine leukosis
Authors: Weber A. F. , Meiske J. C. , Hooker E. C. , Haggard D. L. , Domagala A. M. , Sorensen D. K. , Buoen L. C.
Published: February 2025

In a university beef herd of 304 cattle in which six died of lymphosarcoma between 1980 and 1984, 77% of the Angus and 26% of the Charolais cattle were determined to be infected with bovine leukemia virus (blv). Changes in iatrogenic procedures were initiated as early control measures.

In vitro viral expression (ve) was used as a criterion to identify cattle for subsequent segregation or culling. This involved determinations of percentages of blv-associated lymphocyte profiles among thin-sectioned Ficoll-Paqueisolated blood lymphocytes that were processed into plastic after culture for 48 h. Cattle retained until completion of nutritional studies or as breeding stock were separated into two groups. The blv-seronegative cattle, blv-seropositive cattle with 0% ve, and blv-seropositive cattle with 1% to 4% ve were placed in group 1. Seropositive cattle with ≥ 5% ve were placed in group 2.

In 1985, evaluation of in vitro ve in 108 mature blv- seropositive cattle retained for breeding revealed 36 (33%) had no observable ve. In 1986,58 of 108 cattle were available to be reexamined, and 21 (36%) had 0% ve in both years. The ve expression values for individual cattle were generally comparable over the 2-year period. Of 48 initial seronegative breeding stock housed in group 1 with blv- seropositive cattle with low or no ve, 21 (44%) seroconverted during 1985 to 1986. A positive correlation of 0.585 was found between ve and age-related absolute lymphocyte number.
Auditory brain stem response testing in anesthetized horses
Authors: Rolf Sheri L. , Reed Stephen M. , Melnick William , Andrews Frank M.
Published: February 2025

Auditory brain stem response testing, using insert earphones, was performed in 10 healthy horses given general anesthesia. The procedure involved clicks of alternating polarity delivered at a rate of 25 clicks/s. Wave forms, including five peaks, were commonly identified.

Latencies were measured in milliseconds for waves I through V for all intensities. Latencies of all waves decreased as stimulus intensity increased. For waves I through V, a least-squares regression line was determined for each horse, using all responses between 87-dB sound pressure level (spl) and 136-dB spl, inclusive.

Slopes were significantly (P < 0.05) less than zero for waves I through IV, but not for wave V. Peak latencies of each wave averaged at 87-dB spl for waves I through V were 1.73, 2.6, 3.82, 4.80, and 5.71 ms, respectively; latencies of these five waves at 136-dB spl were 1.36, 2.2, 3.06, 3.92, and 4.71 ms, respectively. The decrease in latency among the five waves ranged from 0.13 to 0.004 ms/dB. When peak values were below 87-dB spl, waves became essentially unrecognizable.
Pathogenesis of rotavirus infection in various age groups of chickens and turkeys: Pathology
Authors: Yason C. V. , Summers B. A. , Schat K. A.
Published: February 2025

Various age groups of turkeys, White Leghorn chickens, and broiler chickens were inoculated with turkey rotavirus strain Tu-2 or with chicken rotavirus Ch-2, and the development of rotavirus-induced lesions were evaluated macroscopically and microscopically (light microscopy and scanning electron microscopy). Morphometric evaluations were conducted to determine morphologic changes in the villi of infected turkeys. Macroscopic lesions that were found in turkeys, but not in chickens, consisted of pallor of the intestinal tract and distension of the cecum with frothy or nonfrothy fluid contents. Histologic lesions in turkeys consisted of basal vacuolation of enterocytes, separation of enterocytes from the lamina propria (with subsequent desquamation), villus atrophy accompanied by widening of the lamina propria, scalloping of the villus surface, fusion of the villi, and leukocytic infiltration of the lamina propria. Scanning electron microscopy indicated roughened villus surfaces, distortion of the normal morphologic features of the villi, and loss of microvilli in cells located on the tips of the villi. Most of the lesions disappeared by 8 days after inoculation. Results of the morphometric evaluations indicated that the crypt length had increased and the villus-to-crypt ratio had significantly decreased, compared with that of noninoculated control turkeys. Broilers ≥ 21 days old and White Leghorn chickens ≥ 35 days old had minimal leukocytic infiltration of the lamina propria and minimal loss of microvilli in cells located on the tips of the villi. The loss of microvilli was more extensive in chickens ≥ 119 days old than in younger birds. Generally, turkeys 1 to 112 days old developed more severe lesions than did chickens, and lesions were more pronounced in turkeys at 112 days of age.
Disposition of fenbendazole in cattle
Authors: Short Charles R. , Barker Steven A. , Hsieh Lily C. , Ou Su-Pin , McDowell Tamera , Davis Lloyd E. , Neff-Davis Carol A. , Koritz Gary , Bevill Richard F. , Munsiff Irene J.
Published: February 2025

Fenbendazole (fbz) was administered to cattle iv and orally in a crossover design. Plasma concentration vs time profiles were reported for fbz and its major metabolites, the sulfoxide (oxfendazole) and the sulfone. The total excretion of fbz and its metabolites in urine and feces was also measured for 6 days after administration. All known metabolites were identified in urine and feces except for fenbendazole amine. Neither this minor metabolite nor p-hydroxyfenbendazole (fbz-oh) appeared in plasma. The major excretory product was fbz-oh. After oral administration, only 44.6% of the dose was eliminated after 6 days, indicating a fairly high degree of sequestration, probably within the gastrointestinal tract.
Circulating proplatelets: Isolation and quantitation in healthy rats and in rats with induced acute blood loss
Authors: Handagama P. J. , Feldman B. F. , Jain N. C. , Farver T. B. , Kono C. S.
Published: February 2025

A technique to isolate megakaryocyte proplatelet processes from blood of rats’ hearts, using colloidal silica coated with polyvinylpyrrolidone density gradient, was developed. The proplatelet concentration in blood from right ventricles was significantly higher (P < 0.001) than that in blood from left ventricles in healthy rats, as well as in rats with induced acute blood loss. The proplatelet concentration of blood from the heart, 24 hours after acute blood loss was induced was significantly (P < 0.001) increased, indicating that platelet production was accelerated. The demonstration of proplatelets entering the pulmonary circulation indicates platelet release via proplatelet formation. Seemingly, proplatelets are fragmented in the lungs at predesignated locations along the proplatelet process.
Effects of dexamethasone, levamisole, and dexamethasone-levamisole combination on neutrophil function in female goats
Authors: Maddux Jeanne M. , Keeton Kerry S.
Published: February 2025

SUMMARY AND CONCLUSIONS

Effects of dexamethasone, levamisole, or combined dexamethasone-levamisole administration on polymorphonuclear neutrophil (pmn) function in healthy, adult female goats were studied. Goats were assigned to treated (n = 6) and control (n = 6) groups. In experiment 1, treated goats were given levamisole (6 mg/kg of body weight, im). In experiment 2, treated goats were given 0.1 mg of dexamethasone/kg, iv, for 3 consecutive days, 1 mg of dexamethasone/kg, iv, for 6 consecutive days, and 6 mg of levamisole/kg, im, with a 4th injection of 1 mg of dexamethasone/kg. All injections were administered 12 hours before blood collection. The pmn were evaluated for random migration and Chemotaxis under agarose, ingestion of Staphylococcus aureus, cytochrome C reduction, iodination, and antibody-dependent cell-mediated cytotoxicity. Levamisole alone did not alter the function of caprine pmn. Both doses of dexamethasone caused increased random migration and decreased cytochrome C reduction and iodination. Dexamethasone resulted in no changes in Chemotaxis, S aureus ingestion, and antibody-dependent cell-mediated cytotoxicity. Random migration and cytochrome C reduction returned toward base line in cells from dexamethasone and levamisole-treated goats. Although iodination activity in cells from dexamethasone-treated goats remained significantly (P < 0.05) lower than those of controls after levamisole administration, a rebound toward base-line activity occurred.
In vitro calibration and surgical implantation of electromagnetic blood flow transducers for measurement of left coronary blood flow and cardiac output in the pony
Authors: Ward D. S. , Fessler J. F. , Bottoms G. D.
Published: February 2025

Electromagnetic flow transducers were implanted via left thoracotomy in 8 ponies (122.7 to 263.6 kg) around the main pulmonary and left main coronary arteries for continuous measurement of mean and pulsatile blood flow. Flow transducers were calibrated in vitro with a gravity flow system. The mean ± se pulmonary flow was 73.1 ± 5.1 ml/kg of body weight/min. Left coronary flow was 0.95 ± 0.07 ml/kg/min (1.3% of cardiac output) and was not believed to be an accurate measurement. This was caused by the inability to implant a zero-flow occluder, requiring the use of minimum flow during systole as zero-flow base line. However, relative changes in left coronary flow were measured. Ponies were maintained up to 5 weeks with no adverse effects. Measurement of mean pulmonary flow with chronically implanted electromagnetic flow transducers provided an accurate continuous measurement of cardiac output with a minimum of restraint.
Immunoglobulin M-specific enzyme-linked immunosorbent assay for serodiagnosis of bovine respiratory syncytial virus infections
Authors: Westenbrink F. , Kimman T. G.
Published: February 2025

An antibody-capture enzyme-linked immunosorbent assay (elisa) for detection of immunoglobulin (Ig) M antibodies to bovine respiratory syncytial virus (brsv) in cattle was developed. Monoclonal antibody to bovine IgM was used as the catching antibody. The IgM-elisa was used, as well as a brsv-specific IgG elisa to determine the kinetics of IgM and IgG antibody responses to brsv infections in cattle.

High IgM and IgG antibody titers developed after naturally occurring or induced brsv infection of calves (6 to 7 months old). Induced infection resulted in an IgM response that was first detectable at postinoculation day (pid) 11 reached a maximum at pid 13, and became undetectable again about pid 28. An IgG response also was detected by pid 11. However, a maximum response was not reached before pid 23, and titers remained high (until pid 80). In naturally occurring infection, IgM and IgG responses in calves were observed in the acute phase of epizootics of respiratory tract disease. Patterns of IgM and IgG response curves were similar to those observed in experimentally infected calves.

The involvement of brsv in an epizootic of respiratory tract disease in 8 calves (2 to 3 weeks old) was demonstrated by the detection of brsv in several lung lavage samples. All calves had existing IgG antibodies to brsv which were interpreted to be maternally derived. None of the calves responded with an increase in IgG antibody titer. However, a weak but distinct brsv IgM antibody response occurred in 6 calves.

To further evaluate the potential of the IgM elisa for diagnostic use, sera of 92 calves involved in 12 epizootics of respiratory tract disease were examined. The brsv infections had been diagnosed in 48 calves using the IgG elisa. An IgM response was detected in 59 calves, including all 48 calves determined to be positive, using IgG elisa. The brsv-specific IgM antibodies were most effectively scored in the sera collected 10 days after the onset of disease.
Fascioliasis in cattle in Louisiana: Development of a system to predict disease risk by climate, using the Thornthwaite water budget
Authors: Malone J. B. , Williams T. E. , Muller R. A. , Geaghan J. P. , Loyacano A. F.
Published: February 2025

A system correlating climate with the annual risk of Fascioliasis in cattle in central Louisiana was developed, using the Thornthwaite water budget and a 6-year data base that included records on herd prevalence rates, transmission to fluke-free sentinel calves, and snail population dynamics. The system developed was compared with modifications of the wet-day and Mt forecasting systems previously developed for use in the oceanic climate zone of western Europe. The wet-day system correlated poorly with transmission data, whereas the Mt and Thornthwaite water budget-derived systems correctly ranked 5 of the 6 years in terms of annual numbers of flukes transmitted to sentinel calves. Compared with the Mt system, the water budget-based system more closely correlated with transmission data, on the basis of statistical regression analysis. The water budget system was calculated by use of a microcomputer software program, and provided a means of measuring the effect of moisture stress and flooding in snail habitats that serve as foci of transmission of Fasciola hepatica to cattle on pastures.
Induction of bovine plaque-forming cells in vitro
Authors: Kaattari S. L. , Nevin B. D.
Published: February 2025

A culture system was developed for the in vitro inoculation of bovine splenic lymphocytes with sheep rbc and trinitrophenylated proteins. The addition of pokeweed mitogen to the cultures was necessary for the induction of plaque-forming cells to the antigen. This culture system required the use of autologous serum and the addition of mitogen.
Radiolocalization of bovine lymphosarcoma cells in athymic mice, using a monoclonal antibody against tumor-associated antigens
Authors: Aida Y. , Ochiai K. , Ito K. , Onuma M. , Fujimori F. , Fujimoto Y. , Izawa H.
Published: February 2025

Mouse monoclonal antibody c 143 was purified and F(ab')2 fragments were generated by pepsin digestion and then radiolabeled with 126I. The 125I-labeled c 143 F(ab')2 fragments were injected into athymic mice bearing bovine lymphoid tumor cells. The fragments became preferentially localized in tumor tissues, but not in normal tissues, as determined by differential counting of tissue radioactivity. The fragments became localized specifically in those tumors that were reactive with c 143 in vitro, but did not become localized in unrelated tumors. Localization of labeled F(ab')2 fragments of a monoclonal antibody of the same isotype directed against Taka virus (a variant of Newcastle disease virus) was not observed in athymic mice bearing bovine lymphoid tumor cells. Tumors were detectable by radioimmunoscintigraphy, using radiolabeled c 143 F(ab')2 fragments, without background subtraction, and by use of silver-grain scattering in light microscopic autoradiography.
Concentrations of carnitine in the seminal fluid of normospermic, vasectomized, and castrated dogs
Authors: Olson Patricia N. , Behrendt Michelle D. , Amann R. P. , Weiss Deborah E. , Bowen Richard A. , Nett Terry M. , McGarry J. Denis
Published: February 2025

Concentrations of total carnitine (free and esterified) were determined in seminal fluids from 12 normospermic dogs before treatment and from the same 12 dogs after assignment to control, vasectomized, or castrated treatment groups (4 dogs each). Before treatment, the mean concentration (± sd) of carnitine in seminal fluid was 946 ± 345 nmol/ml and was not significantly different (P > 0.05) among groups on any seminal collection day. After surgery, mean concentrations of carnitine in seminal fluid from vasectomized and castrated dogs were 49 ± 9 and 14 ± 5 nmol/ml, respectively and were lower (P < 0.001) than the mean concentration in control (sexually intact) dogs. Dogs with obstructive azoospermia may be distinguished from those with aspermatogenesis (secretory azoospermia) by measuring seminal carnitine concentration. Seemingly, the epididymis is the major source of carnitine in canine seminal fluid, because the concentration of carnitine in prostatic fluid was only 58 ± 53 nmol/ml, whereas the concentration of carnitine in 6 pools of epididymal fluid was 18.8 ± 3.9 μmol/ml.
Efficacy of dichlorvos, fenbendazole, and ivermectin in swine with induced intestinal nematode infections
Authors: Marchiondo A. A. , Szanto J.
Published: February 2025

Anthelmintic efficacies of dichlorvos, fenbendazole, and ivermectin were compared in specific-pathogen-free crossbred weanling pigs inoculated with Ascaris suum, Trichuris suis, and Oesophagostomum dentatum. On postinoculation day (pid) 50, 24 pigs in each treatment group were treated orally with 43 mg of dichlorvos/kg of body weight, 3 × 3 mg of fenbendazole/kg, or 300 μg of ivermectin/kg, sc. Twenty-four pigs were not treated. On posttreatment day 7 (pid 57), 12 pigs from each treatment group (phase I) were slaughtered, and the anthelmintic efficacy of each treatment was determined. Efficacies against A suum, T suis, and O dentatum, respectively, were: dichlorvos, 100%, 99.9%, and 100%; fenbendazole, 100%, 99.8%, and 100%; and ivermectin, 98.7%, 53.9%, and 87.6%. Weight gains and feed conversions of the remaining pigs were monitored until they reached market weight (phase II). The average weight gains (kg) and feed conversions (kg of feed/kg of gain) at posttreatment day 81 (pid 131), respectively, were: 73.6 and 3.44 for non-treated controls, 78.9 and 3.31 for dichlorvos-treated pigs; 72.1 and 3.36 for fenbendazole-treated pigs, and 74 and 3.48 for ivermectin-treated pigs. Differences in average weight gains and feed conversions were not significant (P > 0.05).
Serodiagnosis of postnatally and prenatally induced oxoplasmosis in sheep
Authors: Dubey P. , Emond J. P. , Desmonts G. , Anderson W. R.
Published: February 2025

Nineteen pregnant (45 to 90 days of gestation) and 9 nonpregnant ewes were inoculated orally with 1,000 or 10,000 oocysts of Toxoplasma gondii. Pregnant ewes were euthanatized at days 14 (2 ewes), 21 (1 ewe), 23 (1 ewe), 28 (2 ewes), 35 to 42 (6 ewes), and 49 to 62 (6 ewes), and antibody titers in fetal and maternal sera were assayed, using the modified agglutination, latex agglutination, indirect hemagglutination, and dye tests. Although all ewes developed antibody titers of ≥ 1,024 within 28 days after inoculation, fetuses were seronegative up to 28 days, using the modified agglutination test. Toxoplasma gondii antibodies were found in fetuses, using the modified agglutination and dye tests 35 days after ewes were inoculated. Latex agglutination and indirect hemagglutination tests were insensitive for detection of T gondii antibodies in ovine fetal sera. Toxoplasma gondii antibody titers in nonpregnant ewes were similar to those in pregnant ewes. Passively acquired T gondii antibodies from the colostrum decreased from 1,024 to < 16 between 49 and 56 days of age in 1 lamb and between 62 and 106 days in its twin.