bluuebunny/crossref_metadata_2025 huggingface dataset:
Serologic evidence of Legionella infection in horses
Authors: Cho Sang-Nae , Collins Michael T. , Reif John S.
Published: February 2025

The indirect fluorescent antibody test was used to examine 109 samples of equine sera randomly selected from serum pools. Results were compared with titers obtained by the microagglutination (ma) test. A high correlation (r = 0.89) was found between titers measured by the 2 tests. Blood samples were obtained serially from a total of 156 horses at a research farm and the sera were tested against Legionella pneumophila serogroups 1 through 4 using the ma test; 29 horses (19%) seroconverted to at least 1 serogroup of L pneumophila. The indirect fluorescent antibody test substantiated the results obtained by the ma test. Seroconversions in horses provided additional evidence that horses become naturally exposed to legionellae.
Measurement of serum antibody in swine vaccinated with Bordetella bronchiseptica: Comparison of agglutination and enzyme-linked immunosorbent assay methods
Authors: Venier L. , Rothschild M. F. , Warner C. M.
Published: February 2025

The immune responses of 514 pigs from 5 swine breeds (Chester White, Duroc, Hampshire, Landrace, Yorkshire) to vaccination with Bordetella bronchiseptica were measured by agglutination and enzyme-linked immunosorbent assay (elisa) methods. Both assays showed higher antibody levels in sera of pigs after vaccination than in sera of the pigs before vaccination. The variability of the responses among breeds was greater for the agglutination method than for the elisa method. The elisa proved to be more sensitive than the agglutination method and could detect antibody in serum samples diluted at least 100-fold more than those used in the agglutination procedure. The correlation of antibody titers obtained by the 2 methods was small, but statistically (P < 0.01) significant. The elisa should be useful for determinations of antibody responses of swine to B bronchiseptica.
Experimental infection of fetal and newborn Suffolk sheep with scrapie virus
Authors: Hadlow W. J. , Jackson T. A. , Race R. E.
Published: February 2025

SUMMARY AND CONCLUSIONS

Fetal (n = 21) and newborn (n = 7) Suffolk sheep were inoculated with scrapie virus isolated from other Suffolk sheep. Twenty fetuses, 76 to 109 days of gestational age, were inoculated im in the neck through the uterine wall and were examined for virus 47 to 322 days later by mouse inoculation. Scrapie virus was not detected before 254 days of age; only traces of virus were detected in 3 of 7 lambs examined thereafter (2 at 254 days of age and 1 at 322 days of age). Virus was limited to the suprapharyngeal, prescapular, and mesenteric lymph nodes.

Seven lambs were inoculated into the palatine tonsils with scrapie virus as newborns (3 to 12 days old) and were examined for virus when they were 147 to 210 days old. Virus was not detected in the lymphoreticular tissues or terminal portion of ileum of any lamb.

Failure to find scrapie virus in these lambs and in most lambs inoculated as fetuses might indicate few had become infected. However, if most lambs and fetuses had become infected, the long zero phase of the infection could have accounted for failure to find scrapie virus in many of them examined too soon after inoculation. The limited findings of this study indicate that efforts to demonstrate prenatal or neonatal transmission of scrapie by detecting virus are hampered by the slowness of its replication.
Development of enzyme-linked immunosorbent assays for the detection of Fusobacterium necrophorum antibody in animal sera
Authors: Evans J. W. , Berg J. N.
Published: February 2025

Enzyme-linked immunosorbent assays (elisa) for the detection of Fusobacterium necrophorum antibody in the sera of rabbits, cattle, and sheep were developed, using a ribosome-rich extract (rre) from F necrophorum as the antigen. Test character, including optimal antigen dilution and substrate incubation periods, was established, using rabbit, bovine, and ovine antisera produced against rre from isolates of F necrophorum. Rabbit antisera produced against 7 other species of bacteria were used to test the specificity of the F necrophorum rre antigen. Cross-reactivity was not detected. Sera from 50 feedlot cattle were examined with the bovine elisa. Of the 50 samples, 43 (88%) were positive for F necrophorum antibody. The elisa developed in this study were sensitive and specific and appear to be readily adaptable to serologic investigations of F necrophorum.
Evaluation of a technique for measurement of γ-glutamyltranspeptidase in equine urine
Authors: Adams Ragan , McClure Jill J. , Gossett Kent A. , Koonce Kenneth L. , Ezigbo Charles
Published: February 2025

γ-Glutamyltranspeptidase (ggt) activity in equine urine was measured, using an assay developed for use with serum and was found to be reproducible. The ggt activity was measured in samples prepared by serial dilution of exogenous ggt with equine urine, and the activity was determined to be linear between 21 IU/L and 407 IU/L. The behavior of exogenously added ggt was compared in equine serum and urine. The enzyme behaved similarly in both fluids. The ggt activity was measured in serum and urine samples after storage at −20, 4, and 25 C for 24 and/or 72 hours. Enzyme activity decreased after storage at all temperatures and times, but the decrease was greatest and most variable at −20 C. The urine ggt:urine creatinine ratio was calculated on serial urine samples collected over 24 hours, Although the urine ggt activity and creatinine concentration had significant variation, the ratio remained constant. The urine ggt:urine creatinine ratio was calculated from random urine samples collected from 27 clinically healthy adult horses and was found to be 10.52 ± 4.78 (mean ± sd).
Heavy metals in fluids and tissues of fetal calves and in young calves of nursing cows exposed or not exposed to anaerobically digested wastewater sludge
Authors: Fitzgerald Paul R. , Peterson James , Lue-Hing Cecil
Published: February 2025

Fetal fluid, diaphragm muscle, heart, kidney, and liver from 14 four- to five-month-old calf fetuses were analyzed for Zn, Cu, Cd, Cr, Ni, Pb, and Fe. The same tissues and bone were examined from postparturient calves 30, 60, and 120 days of age. Weaned calves (8 to 9 months old) were necropsied and diaphragm muscle, heart, kidney, liver, brain, and bone were analyzed. Additional calves from cows exposed or not exposed to anaerobically digested sludge were placed in a feed yard at weaning for a feeding period of 150 days and then were killed and necropsied. Heavy metal content of the aforementioned tissues was compared with the same tissues obtained from peer calves weaned, killed, and necropsied 150 days earlier.

Zinc, Cu, and Fe were up to 11 times higher in fetal livers than in control or exposed postparturient calves. These concentrations declined after birth and stabilized at approximately the concentrations observed in adult cattle at about 12 to 14 months of age. Cadmium accumulated to a greater extent in kidneys and livers of exposed calves than in control calves. However, the accumulation did not produce a detectable effect upon the functional or morphologic characteristics of the organs examined. Other metals were present at low levels and were generally not remarkably different in control and exposed animals.
Effect of Escherichia coli endotoxin and thyrotropin-releasing hormone on prolactin in lactating sows
Authors: Smith Bradford B. , Wagner W. C.
Published: February 2025

Primiparous gilts were given subcutaneous injections of saline solution or 8 mg of Escherichia coli endotoxin (055:B5 strain) in saline solution on postpartum days (ppd) 2 and/or 6 and saline solution at the same site on PPD 1, 3, 5, and 7 at 1000 hours. On ppd 1 to 3 and on ppd 5 to 7, pigs were given 100 μg of thyrotropin-releasing hormone (trh) iv at 1300 hours to evaluate trh-induced prolactin (prl) release. Blood samples were analyzed for prl, cortisol, triiodothyronine (T3), and tetraiodothyronine (T4) concentrations. Rectal temperatures were monitored at hourly intervals between 0800 and 1500 hours on ppd 2 and 6.

The prl declined after endotoxin administration on ppd 2, but a similar decline was not seen after saline solution administration on ppd 1, 2, or 3. The prl concentrations remained unchanged on ppd 5, 6, and 7 in gilts exposed to endotoxin for the 1st or 2nd time on ppd 6 and to saline solution on ppd 5 and 7. The trh injection caused increases in prl in all animals, but the prl increase after trh injection was significantly lower (P < 0.05) in gilts treated with endotoxin on ppd 2.

Cortisol concentrations increased after endotoxin exposure on ppd 2 and 6. Rectal temperatures increased after endotoxin exposure on ppd 2 and 6 with peak temperatures of 41.8 C and 41.6 C seen 4 and 3 hours, respectively, after endotoxin injection. The T3 and T4 response, used as an indicator of trh perfusion of the adenohypophysis, was unchanged after endotoxin or saline solution administration.
Experimental reproduction of septicemic pasteurellosis in feedlot lambs: Bacteriologic and pathologic examinations
Authors: Suàrez-Güémes Francisco , Collins Michael T. , Whiteman Charles E.
Published: February 2025

Septicemic pasteurellosis (sp) was induced in feedlot lambs. Twenty-eight lambs, randomly allotted into 7 groups, were given combinations of 3 treatments: (1) immunosuppression using hydrocortisone solubilized in dimethyl sulfoxide, (ii) rapid changes in feed, from 100% roughage to 90% concentrate, and (iii) oral inoculation of Pasteurella haemolytica biotype T. Feed changes and immunosuppression by hydrocortisone were needed for the production of sp. Pasteurella haemolytica inoculation was not necessary for induction of sp in all cases, indicating an endogenous source of infection. Clinical pathologic, bacteriologic, and gross and microscopic pathologic findings of induced sp were similar to those described for naturally occurring sp in lambs. Infection of lambs with P haemolytica biotype T via the gastrointestinal tract is discussed as a possible step in the pathogenesis of sp in feedlot lambs.
Measurement of portal and hepatic blood flows using a modified method for surgical placement of catheters in the major splanchnic vessels of sheep
Authors: Naylor J. M. , Freeman D. E. , Richardson D. , Kronfeld D. S.
Published: February 2025

A modified catheterization and para-aminohippurate dye dilution technique was used to measure portal and hepatic blood flows in sheep. Blood flows (mean ± 1sd) for 7 healthy sheep were 1.54 ± 0.71 L/min and 1.98 ± 0.75 L/min for portal and hepatic flows, respectively. Blood flow measurement was facilitated when dye injection rates produced blood para-aminohippurate acid concentrations >15 mg/L. Uniform mixing of dye with blood was confirmed in 1 sheep with 2 portal vein catheters.

Surgery to place the catheters was facilitated by using a ventral paracostal approach. Blood gas analysis was useful in confirming the placement of the catheters.

Useful catheter life in this experiment was 41 days, which was longer than in previous reports. Treating the catheters with an organo-silane preparation, protecting the catheters against dislodgement, and use of a belly bandage to minimize damage to the external parts of the catheter may have prolonged catheter life in this experiment.
Expression of type 1 pili by Escherichia coli strains of high and low virulence in the intestinal tract of gnotobiotic turkeys
Authors: Dominick M. A. , Schmerr M. J. F. , Jensen A. E.
Published: February 2025

Highly virulent (strain 1) and weakly virulent (strain 3) Escherichia coli were examined using immunofluorescent and electron microscopic techniques to determine their ability to express type 1 pili in the intestinal tract of 3-week-old gnotobiotic turkeys. Turkeys were necropsied on postinoculation day (pid) 1, 2, 5, 8, and 12. Nonpiliated forms of strains 1 and 3 were more numerous than piliated forms in cecal and colonic contents examined by negative staining electron microscopy. A piliated form of strain 1 was seen in intestinal contents on each pid and was more numerous in cecal contents than in colonic contents. The mucus blanket of the cecum and colon contained large numbers of bacteria, although organisms were rarely intimately associated with the intestinal epithelium. Immunofluorescent staining indicated large numbers of piliated forms of strains 1 and 3 within the mucus blanket of the cecum and colon on pid 2, 5, 8, and 12. Piliated bacteria were infrequently seen in the ileal mucus blanket. Serum antibody titers to type 1 pili increased markedly by pid 5 and persisted in turkeys inoculated with strain 1. In contrast, antibody titers in turkeys exposed to strain 3 increased gradually and varied markedly among birds at each pid. Type 1 pili may not be important for adherence of pathogenic E coli to intestinal epithelium of turkeys.
Influence of dietary calcium on lead poisoning in mallard ducks (Anas platyrynchos)
Authors: Carlson Brent L. , Nielsen Svend W.
Published: February 2025

Forty-five mallard ducks were allotted into 3 dietary groups. Group I was fed pelleted calcium-supplemented corn; group II was fed a pelleted commercial duck ration; and group III was fed cracked corn. Ten ducks of each group were given four No. 4 lead shot via an esophageal tube, and 5 ducks of each dietary group were kept as pair-fed controls. Anorexia and weight loss were most severe in the treated group III ducks. Group III had a maximum reduction in food consumption of 87% followed by a slight improvement in appetite; they lost 35% of their initial body weight. Group I treated ducks had a reduction in food consumption of 64% that eventually returned to the quantities consumed at the start of the experiment; group I ducks lost 18% of their initial body weight. Group II treated ducks maintained healthy appetites during the experiment and had a weight gain of 2% of their initial body weight. The number of ducks that became moribund and were euthanatized differed significantly among the treated groups with 100% of group III, 50% of group I, and 0% of group II treated ducks becoming moribund.

All 3 groups of treated ducks had increased protoporphyrin IX concentrations compared with controls. Groups I and III lead-treated ducks had significant (P < 0.05) reductions in erythrocyte counts, pcv, hemoglobin concentrations, and mean corpuscular hemoglobin concentrations as compared with controls. Group II had reduced hemoglobin concentration and mean corpuscular hemoglobin concentration compared with controls. However, none of the above changes differed statistically among the 3 dietary groups of lead-poisoned ducks.

Gross pathologic lesions of treated ducks (pectoral muscle atrophy and green discoloration of the gizzard mucosa) were most pronounced in group III, followed by group I and group II, in that order. Histopathologic lesions consisting of neuropile vacuolization, intranuclear inclusion bodies, neuronal degeneration, and myocardial and pectoral muscle degeneration, necrosis, and atrophy occurred most frequently in the group III treated ducks, less in the group I treated ducks, and least in the group II treated ducks. This suggested that, whereas the addition of calcium to the corn diet had an ameliorating effect, other nutrients were also important in mollifying lead absorption and metabolism in mallard ducks.
Serum antiprotease concentrations in dogs with spontaneous and experimentally induced acute pancreatitis
Authors: Murtaugh R. J. , Jacobs R. M.
Published: February 2025

A significant decline (P = 0.047) in serum antiprotease concentration was detected in dogs with experimentally induced acute pancreatitis. Decreased serum antiprotease concentrations, similar in magnitude to those documented in the experimental dogs, were present in dogs with spontaneous, acute pancreatitis. These findings suggest that significant amounts of proteolytic enzymes escape into the systemic circulation during acute pancreatitis in dogs. These circulating enzymes may be involved in the extrapancreatic complications of acute pancreatitis.
Q fever serologic surveillance program for sheep and goats at a research animal facility
Authors: Singh Suraj B. , Lang C. Max
Published: February 2025

Since Q fever is a potential risk to personnel working with small ruminants, the serologic status of sheep and goats received at a medical school animal facility for research was evaluated. A total of 104 sheep and 102 goats were subjected to blood sample-collection procedures on arrival,, as well as after a 2-week quarantine period, and the sera were tested for Q fever specific antibodies by complement-fixation (cf) and microagglutination (ma) tests. The results from the 2 tests were compared and analyzed for seroconversion. On the basis of the cf test, 14 sheep and 3 goats were considered positive; these included 7 sheep and 2 goats that seroconverted during the quarantine period. In contrast, 1 sheep and 5 goats were found positive by the ma test, which also detected seroconversion of 1 sheep and 1 goat. The use of both tests for serologic surveillance of Q fever in sheep and goats increased the likelihood of detection. Management safety practices are also required to minimize the risk of disease transmission.
Inhibition of phagosome-lysosome fusion in macrophages by soluble extracts of virulent Brucella abortus
Authors: Frenchick Patrick J. , Markham R. J. Frederick , Cochrane Annette H.
Published: February 2025

Water extracts of virulent Brucella abortus were able to inhibit phagosome-lysosome fusion in unelicited murine peritoneal macrophages following ingestion of yeast. Extracts from an avirulent strain were unable to produce a similar effect. Lipopolysaccharide from B abortus did not appear to be involved with the ability of the extracts to inhibit fusion.
Alleviation of excessive gas accumulation in the ruminant stomach by ritanserin
Authors: Ruckebusch Y. , Ooms L. A. A. , Degryse Anne-D. , Allal Ch.
Published: February 2025

The relationships between forestomach motility and eructation rate were studied in sheep and cattle. Three ewes and 2 heifers were implanted with strain gauges on the reticulo-rumen and fitted with a cannula in the dorsal sac of the rumen. Studies were performed in sheep after induction of hypocalcemia by Na2EDTA infusion and cattle were studied after ruminal distension. Experiments were performed by measuring the rate and volume of eructated ruminal gases, using a technique by which the trachea is transected.

The frequency of reticulo-ruminal contractions decreased 40% within 30 minutes of Na2EDTA infusion to the sheep. The volume of eructated gas (for 30-minute periods) decreased from 10.7 L to 5.5 L at the end of the 60-minute infusion period. Pretreatment with ritanserin (0.1 mg/kg, subcutaneously) not only prevented bloating during the ruminal stasis induced by hypocalcemia, but also significantly increased the eructated volume of gas.

In cattle, ritanserin given at the same dose level (0.1 mg/kg, subcutaneously) significantly increased the volume of eructated gas after ruminal distension.

This study supports the hypothesis that the caudal esophageal sphincter has a role in the rate of ruminal gas eructation and indicates that its relaxation may be due to a 5-hydroxytryptamine antagonist.
Poikilocytosis in dogs with chronic doxorubicin toxicosis
Authors: Badylak Stephen F. , Van Vleet John F. , Herman Eugene H. , Ferrans Victor J. , Myers Charles E.
Published: February 2025

Peripheral blood smears made during 2 studies of chemical antidotes for doxorubicin (drb) cardiotoxicity in dogs were examined to determine the incidence of poikilocytosis. The 1st study had significantly (P < 0.05) increased numbers of poikilocytes in 3 groups of 5 dogs, each treated with drb alone, drb plus thyroxine (0.5 mg/day), and drb plus thyroxine (2.0 mg/day), respectively, compared with 1 group of 5 dogs treated with thyroxine alone (2.0 mg/day). In addition, the drb-treated dogs had regenerative anemia characterized by an increased reticulocyte index. The 2nd study had a significant (P < 0.05) increase in poikilocytes in 4 groups of 6 dogs, each treated with drb alone, drb plus ± -1,2-bis(3-5-dioxopiperazinyl-1-yl; icrf-187), drb plus N-acetylcysteine (nac), and drb plus icrf-187 plus nac, respectively, compared with 4 groups of 3 dogs, each treated with icrf-187 plus saline solution (ss), nac plus ss, icrf-187 plus nac plus ss, and ss alone, respectively. In both studies, the poikilocytes were identified as echinocytes, spiculated erythrocytes, and schizocytes. Administration of thyroxine and icrf-187 did not prevent the occurrence of poikilocytosis in drb-treated dogs. Administration of nac with drb resulted in a mild decrease in the extent of poikilocytosis compared with that observed in dogs given drb alone. The hematologic changes observed in both studies were not accompanied by adverse clinical signs referable to the drb-induced alterations in erythrocytes.
Experimental bovine respiratory syncytial virus infection in conventional calves: Light microscopic lesions, microbiology, and studies on lavaged lung cells
Authors: Castleman W. L. , Lay J. C. , Dubovi E. J. , Slauson D. O.
Published: February 2025

Conventionally raised male Holstein calves, 1 month of age, were infected by intranasal and intratracheal inoculation with bovine respiratory syncytial virus. Viral antigen was identified by fluorescence microscopy most commonly in the cytoplasm of tracheal and bronchial epithelial cells 3 to 5 days after inoculation. Cytoplasmic viral antigen was identified also in nasal, nasopharyngeal, bronchiolar, and alveolar epithelial cells and in alveolar macrophages. Bronchitis and tracheitis, characterized in part by epithelial necrosis, formation of syncytial epithelial cells and epithelial hyperplasia, were the most common lesions observed histologically. Rhinitis, bronchiolitis, and interstitial pneumonia were observed less frequently. Alterations were not detected in the numbers of cells recovered by bronchoalveolar lavage after inoculation. An increase in the phagocytic rate of latex beads occurred in macrophages 5 days after inoculation. Viral-induced lesions were resolved by 30 days after inoculation. The results indicated that bovine respiratory syncytial virus inoculation of calves results in reversible alterations in airway epithelial structure and in the phagocytic function of alveolar macrophages.
Severe clinical disease induced in cattle persistently infected with noncytopathic bovine viral diarrhea virus by superinfection with cytopathic bovine viral diarrhea virus
Authors: Bolin S. R. , McClurkin A. W. , Cutlip R. C. , Coria M. F.
Published: February 2025

Eight healthy cattle that were persistently infected with noncytopathic bovine viral diarrhea virus (bvdv) were inoculated with cell culture fluids that contained noncytopathic or cytopathic bvdv. A severe disease occurred after inoculation with cytopathic bvdv. The clinical signs, lesions, and immune response were consistent with those of clinical bvdv infections.
Effects of experimentally induced Pasteurella haemolytica pneumonia on the pharmacokinetics of erythromycin in the calf
Authors: Burrows G. E.
Published: February 2025

Pneumonic pasteurellosis was produced experimentally in 3- to 4-month-old Holstein bull calves by bilateral intrapulmonary administration of 5 × 107 to 109 colony-forming units of Pasteurella haemolytica. Of 8 calves, 4 developed minor pulmonary changes, 1 died of an apparent bacteremia within 24 hours, and 3 developed extensive pneumonic changes. At 1 week before (1 dose) and at 48, 60, and 72 hours (3 doses) after Pasteurella administration, the calves were given erythromycin at a dosage of 15 mg/kg, and the pharmacokinetic values were determined. There were statistically (P ≤ 0.05) significant increases in the distribution and elimination rates associated with pneumonia. The elimination half life decreased from 132.7 ± 9.6 minutes in prepneumonic calves to 111.1 ± 13.8 minutes and 99.7 ± 2.6 minutes in calves with minor and with moderate pneumonic changes, respectively. There also was a decrease in apparent volume of distribution with pneumonia. Erythromycin tissue concentrations were determined 2 hours after the last dose was given to the calves with pneumonia. Tissue concentrations in the pneumonic lung areas were as high or higher than those in nonaffected lung tissues in the same animals. Because of the increased rate of elimination from serum in pneumonic calves, it may be advisable to use shorter dosage intervals in calves with severe respiratory tract disease.
Blood from bovine leukemia virus-infected cattle: Antigen production correlated with infectivity
Authors: Miller L. D. , Miller J. M. , Van Der Maaten M. J. , Schmerr M. J. F.
Published: February 2025

Leukocytes from 1 ml of blood from cattle seropositive to the bovine leukemia virus were cultured for 3 days and then tested by radioimmunoassay for antigen production. Infectivity of blood from each animal was also tested by calf inoculation and subsequent serologic detection of bovine leukemia virus transmission by agar-gel immunodiffusion. In a preliminary experiment, blood from each of 3 antigen-positive cattle was inoculated intracutaneously into 2 calves in volumes of 20 or 100 μl. Blood from each of 4 antigen-negative cattle was similarly inoculated into 3 calves in volumes of 20, 100, or 500 μl. At the termination of the experiment (8 weeks after inoculation), all 6 calves given blood from antigen-positive cattle had seroconverted, and 11 of 12 calves given blood from antigen-negative cattle had seroconverted.

In a 2nd experiment, blood from each of 2 antigen-positive and 2 antigen-negative cattle was inoculated into pairs of calves in volumes of 1, 10, or 20 μl. At the end of the experiment (12 weeks after inoculation), all calves inoculated with blood from antigen-positive cattle had seroconverted, but only 6 of 12 calves that had been given blood from antigen-negative cattle had seroconverted. The relative infectivity of blood was best illustrated by comparing results from the 1-μl inoculations. At that volume, the 4 calves given blood from antigen-positive cattle were infected, whereas none of 4 calves given blood from antigen-negative cattle was infected.
Infectious bovine keratoconjunctivitis: Subconjunctival administration of a Moraxella bovis pilus preparation enhances immunogenicity
Authors: Pugh Geogge W. , Kopecky Kenneth E. , McDonald Timothy J.
Published: February 2025

To compare the immune response elicited by 3 routes of vaccination, 36 calves were randomly allotted to 4 groups of 9 calves each. Group I was vaccinated subconjunctivally only. Group II was vaccinated concomitantly, both subconjunctivally and in the dewlap. Group III was vaccinated in the dewlap only. Group IV was not vaccinated and served as a virulence control for the Moraxella bovis culture. Calves in groups I, II, and III were given 2 inoculations with 14 days between inoculations. Twenty-one days after the last inoculation, the ventral conjunctival sac of all calves was instilled with cells of a virulent M bovis strain.

After challenge exposure, all vaccinated calves (groups I, II, and III) had evidence of enhanced resistance, compared with the nonvaccinated calves. The highest to lowest gradients of immune responsiveness were: Group I ≥ group II > group III > group IV. When immune criteria, such as the percentage of diseased eyes, the mean duration of infection, the severity of corneal lesions, and the serologic response were compared, groups I and II were significantly (P < 0.05) more resistant to challenge exposure than were groups III and IV. Group III was significantly (P < 0.05) different from group IV in severity of lesions and in serologic response. Also, the mean duration of infection was shorter, and the percentage of diseased eyes was less in group III than in group IV (P > 0.10). Group I was more resistant than was group II (P < 0.10).

The overall results indicated that subconjunctival vaccination induced a better immune response than did subcutaneous dewlap vaccination.
Experimental porcine eperythrozoonosis; T-lymphocyte suppression and misdirected immune responses
Authors: Zachary James F. , Smith Arnold R.
Published: February 2025

Immune responses and hematologic alterations were investigated in splenectomized pigs after im inoculation with Eperythrozoon suis. Early hematologic alterations were massive parasitism of rbc, severe hypoglycemia, moderate bilirubinemia, and mild anemia; later findings included severe anemia, minimal parasitism of rbc, spontaneous agglutination of rbc at 25 C and 4 C which was reversible at 37 C, transient thrombocytopenia, and mild bilirubinemia. The humoral immune responses consisting of a transitory hyperglobulinemia and increase of indirect hemagglutination (iha) titers against E suis were attributed to immunoglobulin M cold agglutinins. Cell-mediated immune responses, measured by phytohemagglutinin- and pokeweed mitogen-induced lymphocyte blastogenesis, were reduced after massive parasitemia. Blastogenesis induced by Escherichia coli lipopolysaccharide mitogen was increased before the hyperglobulinemia and an increase in iha titer. There was an increase in the uptake of [3H]thymidine by lymphocytes cultured without mitogens after the decline in total globulin concentration and iha titer.
Regional distribution of porcine brain blood flow during 50% nitrous oxide administration
Authors: Manohar Murli
Published: February 2025

Regional distribution of brain blood flow was examined in 6 healthy nonmedicated swine during inhalation of 50% O2 (+ 50% N2) and at 45 minutes of 50% end-tidal nitrous oxide administration. All animals were surgically prepared 10 to 12 days before the hemodynamic study. Catheters were implanted in the left atrium, ascending aorta, descending aorta, and pulmonary artery. Brain blood flow was determined, using 15-μm diameter radionuclide-labeled microspheres injected into the left atrium. Administration of 50% nitrous oxide markedly increased blood flow in all regions of the brain (except corpus callosum), even though the animals were not excited and the arterial blood pressure, arterial blood-gas tensions, pHa, and cardiac output were not different from respective control values. At 45 minutes of 50% nitrous oxide administration, cerebral, cerebellar, and brain-stem blood flows were 144%, 137%, and 137% of respective control values. It is concluded that 50% nitrous oxide administration caused marked vasodilatation in all regions of the porcine brain.
Relative oxytocic properties of fenprostalene compared with cloprostenol, prostaglandin F2α, and oxytocin in the ovariectomized ewe
Authors: Garcia-Villar R. , Marnet P. G. , Laurentie M. P. , Toutain P. L.
Published: February 2025

The oxytocic effect of a prostaglandin F2α analogue, fenprostalene, was assessed in 4 ovariectomized ewes fitted with electrodes in both uterine horns and in the cervix. In the absence of estradiol priming, significant motility changes were not elicited by fenprostalene. Conversely, when ewes were primed with 17-β-estradiol, fenprostalene markedly increased the electrical activity in the uterus and cervix. After a single subcutaneous fenprostalene administration (5 μg/kg), activity values remained about twice that of the control values during 8.52 ± 3.31 hours. When the same dosage was administered im, similar post-injection activity values were obtained, but only during 5.88 ± 0.72 hours. Oxytocic effects of fenprostalene were far longer than those elicited by a single im administration of 50 μg of prostaglandin F2α (tham salt)/kg (0.91 ± 0.32 hours) or by a single im administration of 1 μg of cloprostenol/kg (1.88 ± 0.81 hours). Using the dose-effect relationship curve obtained from the same ewes by continuous iv infusions of oxytocin (oxt), the postinjection activity values reached after a single subcutaneous administration of fenprostalene were equivalent to those of an iv infusion of oxt at an average dose of 4.09 ImU of oxt/kg/hr for 6 to 13 hours, according to the values of the particular ewe concerned. These long-lasting oxytocic properties, in addition to its luteolytic capabilities, would make fenprostalene a suitable drug for promoting effective evacuation of the uterus when required in daily veterinary practice.
Brain stem auditory-evoked potentials of dogs: Wave forms and effects of recording electrode positions
Authors: Holliday Terrell A. , Te Selle Marian E.
Published: February 2025

Wave forms of canine brain stem auditory-evoked potentials (baep) and the effects of electrode positions on the wave forms were studied as a basis for experimental and clinical use of baep recording. The baep regularly consisted of 5 waves (I to V) with latencies and polarities similar to those of other species. In some dogs, waves II, III, and IV contained distinct subpeaks (a, b, c). Waves similar to waves VI and VII of other species were recorded in some dogs.

With respect to baep, no site on the head was electrically inactive and baep could be recorded as far caudally as the caudal cervical region in some dogs. Wave I, positive in recordings from the dorsal midline of the calvaria (vertex) underwent polarity reversal and increased amplitude and duration in recordings made from caudal ventrolateral regions of the head (mastoid region). As a result, wave I partially or totally obscured wave II so that the latter could no longer be clearly identified. Waves IIIa and IIIb were differentially affected by moving the recording site, indicating that their generators were spatially separated. Waves IV and V were also affected by electrode site, consistent with previous reports that they have spatially separated generators in other species.

In recordings made with vertex electrodes referenced to the mastoid region ipsilateral to the stimulated ear, wave I appeared as a high-amplitude positive peak with onset latency equalling that in noncephalic reference recordings, but with somewhat later peak latency and longer duration. As a result, wave II was partially or totally obscured so that only 4 major peaks were evident in the baep. In contralateral mastoid reference recordings, latency to peak of wave I was unchanged; however, amplitude of all waves was reduced and waves IIa and IIb were not as clearly differentiated as they were in noncephalic reference recordings.
Properties of a respiratory syncytial virus isolated from a sheep with rhinitis
Authors: Evermann J. F. , Liggitt H. D. , Parish S. M. , Ward A. C. S. , LeaMaster B. R.
Published: February 2025

A virus isolated from a yearling cross-bred ewe was identified as respiratory syncytial virus (rsv) by indirect immunofluorescence and by virus neutralization with bovine rsv antisera. The virus caused a mild conjunctivitis in 3-month-old lambs when inoculated alone. Although clinical signs of pneumonia were not observed, there was gross and microscopic evidence of pulmonary inflammation in the lungs of lambs inoculated with either the sheep rsv isolate alone or in conjunction with Pasteurella haemolytica. Lung lesions in the dual infection were more severe, with approximately 10% of the total lung mass affected. Lavage fluids from lambs inoculated with virus and bacteria contained approximately 3 times more inflammatory cells than from control lambs or lambs inoculated with virus only. The sheep rsv isolate was classified as a mild respiratory pathogen in lambs of this age. Speculations on the potential importance of this virus in interspecies transmission to cattle and goats were discussed.
Clinical, biochemical, acid-base, and electrolyte abnormalities in cats after hypertonic sodium phosphate enema administration
Authors: Atkins Clarke E. , Tyler Ron , Greenlee Paul
Published: February 2025

Ten clinically healthy cats were allotted into 2 groups. Group A was given the low (60 ml), and group B was given the high (120 ml) recommended dose of a commercial hypertonic sodium phosphate enema. Enema retention was enforced. All cats developed clinical and/or laboratory abnormalities, with group B cats being more severely affected. Clinical signs that occurred rapidly included depression, ataxia, vomition, bloody diarrhea, mucous membrane pallor, and stupor; tetany was not seen. One cat in group B died. Laboratory abnormalities included hypernatremia, hyperphosphatemia, hypocalcemia, hyperglycemia, calculated hyperosmolality, and metabolic acidosis with high anion gap probably due to hyperlacticacidemia. There were no significant gross or microscopic lesions associated with enema administration. Therefore, the use of hypertonic sodium phosphate enema at recommended doses is potentially dangerous to cats.
Preliminary study of ethylene oxide sterilization of full-thickness cortical allografts used in segmental femoral fracture repair
Authors: Johnson Ann L. , Shokry M. M. , Stein L. E.
Published: February 2025

Full-thickness canine cortical allografts were cleanly harvested, sterilized with ethylene oxide, and stored at room temperature. The allografts were incorporated into canine segmental femoral fracture repairs and compared clinically, radiographically, and morphologically with control femoral cortical autografts for function of the limb, graft acceptance, and bone union. Sterility was maintained and the cortical allografts were well accepted by the host animals, resulting in full use of the limb which was subjected to surgical operation. The allografts showed healing patterns similar to those of the autografts, as determined by radiographic, gross, and histologic evaluation of the proximal and distal host-graft interfaces. Evaluations were made monthly. The host-graft interfaces of the allografts and autograft were filled with woven bone with adjacent vascular invasion and remodeling of the graft at the final 4th-month evaluation.
Estimation of urine flow rate in mares
Authors: Gronwall Ronald , Price George
Published: February 2025

To determine the rate of urine flow and thus urinary excretion in the horse from untimed urine samples alone, the flow rate, creatinine concentration, osmolarity, and refractive index of 228 quantitatively collected urine samples were determined in 53 experiments on 12 healthy Thoroughbred mares. Forty samples were collected after waterinduced diuresis; 11 samples were collected after furosemide-induced diuresis. Flow rates, which ranged from 1.2 to 84.5 ml/min, could be predicted from the urinary creatinine concentration. Correlation of urinary flow with urinary creatinine concentration accounted for 94% of the variability in the urinary flow rates. Phenylbutazone was administered before collection of 168 urine samples. Urine flow rates that were predicted from urinary creatinine concentration were used to estimate phenylbutazone excretion. Urine flow could be estimated without quantitative urine collection.
Immunologic abnormality in a group of Macaca arctoides with high mortality due to atypical mycobacterial and other disease processes
Authors: Holmberg Charles A. , Henrickson Roy , Lenninger Ron , Anderson John , Hayashi Linda , Ellingsworth Larry
Published: February 2025

Of 54 Macaca arctoides, 44 died during the 2.5 years after their assignment to a common cage. Although early deaths were due to trauma, acute gastric dilatation, and shigellosis; latter deaths were the result of a variety of uncommon diseases including atypical mycobacterial disease, malignant lymphoma, protozoan encephalomyelitis, and other necrotizing and inflammatory lesions.

Atypical mycobacterial disease due to Mycobacterium avium intracellular serotypes was the most frequent single disease agent recognized (33% [18 macaques]). This disease began in the ileum and large intestine with subsequent systemic involvement. An abnormality of host response to infective agents, in general, was indicated by the unusually high occurrence of this disease, as well as other disease processes. Morphologic evaluation of lymphoid organs revealed decreased cellularity of follicles and decreased numbers of plasma cells in all macaques, whereas T cell-dependent areas varied from hypocellular to hypercellular with 5 macaques with malignant lymphoma. The spontaneous erythrocyte rosette-forming subpopulation of T cells was decreased in peripheral blood, but was increased in lymph nodes containing atypical mycobacterial lesions.

Serum immunoglobulin value decreased progressively in diseased macaques. A basic abnormality of T-cell subpopulations controlling other components of host response was suspected. Macrophages from lesions that contain mycobacterial organisms did not phagocytize latex beads normally in vitro, whereas monocytes in the blood of the same macaques were capable of in vitro phagocytosis.
Ornithodoros coriaceus (pajaroello tick) as a vector of bluetongue virus
Authors: Stott Jeffrey L. , Osburn Bennie I. , Alexander Lisa
Published: February 2025

Preliminary studies demonstrated that the argasid tick, Ornithodoros coriaceus Koch, could become infected with bluetongue virus (btv). Ticks became infected after feeding through artificial membranes on btv infected suspensions of cell cultures, chicken embryos, and sheep blood. Ticks also became infected after natural feeding on viremic sheep (btv serotype 17) and cattle (btv serotype 11). Virus was recovered from the hemolymph and salivary glands of ticks which had ingested btv either through an artificial membrane or by natural feeding on a host animal. Ticks infected with btv serotype 13 were capable of transmitting the virus to a susceptible cow at 42 days after ingestion of virus-infected cultures, thus demonstrating the potential of the tick to serve as a biological vector of btv.
Alterations in coagulation and hemograms of horses given endotoxins for 24 hours via hepatic portal infusions
Authors: Duncan S. G. , Meyers K. M. , Reed S. M. , Grant B.
Published: February 2025

This experiment was designed to establish a model for the study of gastrointestinal disturbances as a result of prolonged endotoxin uptake in the horse. The hepatic portal vein of 7 horses was catheterized (through flank incisions) to give chronic hepatic portal infusions of lipopolysaccharide (lps, endotoxin). Lipopolysaccharide was infused at a rate of 1 μg/kg of body weight/hr for 24 hours. Two of the horses were infused with saline solution for 12 hours before lps infusions were given.

Lipopolysaccharide was shown to affect behavior and hematologic and coagulation values. The 1st hour was critical for the lps-infused horses; yet by 4 hours, the horses had apparently become refractory to continued infusion of lps. During the 1st hour, all horses collapsed without an accompanying hypotension. A decrease in polymorphonuclear leukocytes (neutrophils) was seen during this time and was accompanied by a shortening of the recalcification tests, 1-stage prothrombin time, and activated partial thromboplastin time. There was an increased concentration of circulating fibrinogen/fibrin degradatory products. All of the lps-infused horses showed signs of hoof discomfort and either stood with the 4 feet together beneath the body or continually shifted their weight from one front foot to the other. Hoof temperature decreased approximately 3 degrees (C) during this time and remained decreased for the duration of the experiment.
Comparison of the healing of prescrotal urethrotomy incisions in the dog: Sutured versus nonsutured
Authors: Weber William J. , Boothe Harry W. , Brassard Jacqueline A. , Hobson H. Philip
Published: February 2025

Comparison was made of the healing of sutured prescrotal urethral incisions (12 dogs) with that of nonsutured incisions (6 dogs). Comparison was also made of the healing of 5-0 polyglactin 910-sutured urethral incisions (6 dogs) with that of 5-0 polydioxanone-sutured incisions (6 dogs). Three dogs from each treatment group were euthanatized 3 weeks and 6 weeks after the surgical procedure. Surgical sites were examined grossly, and urethral circumference measurements were taken at 3 locations (surgical site, 1 cm cranially, and 1 cm caudally). Transverse sections of the surgical sites were prepared and examined by light microscopy.

Hemorrhage occurred postoperatively in dogs in which the incisions were not sutured. The surgical sites from the 6 dogs in which incisions healed by second intention had more fibrosis and less inflammation than did those that were sutured. There was little difference between incisions sutured with polyglactin 910 and those sutured with polydioxanone suture material. Postoperative urethral stricture formation did not occur in any of the dogs.
Hemorrhage from the cosmetic otoplasty of Doberman Pinschers with von Willebrand’s disease
Authors: Johnson Gary S. , Schlink Gerald T. , Fallon Ronald K. , Moore Cecil P.
Published: February 2025

The hemorrhagic tendencies of 23 Doberman Pinscher pups were observed during cosmetic otoplasty and were ranked by a +1 to +4 grading system (+1 = least hemorrhage, and +4 = most hemorrhage). A second estimate of the hemostatic competencies of these dogs was made by counting the gauze sponges used in the otoplasties. Factor VIII-related antigen concentrations and coagglutinin cofactor concentrations were measured in plasma samples from blood drawn not more than 30 hours before the surgical procedures were done. The factor VIII-related antigen concentrations were between 9% and 147% of the concentration in a normal plasma pool, and the coagglutinin cofactor concentrations were between 1% and 165%, indicating that some of these dogs had von Willebrand’s disease. The hemorrhagic tendencies of 12 pups were graded +1. This group had a mean antigen concentration of 75% (min-max, 38% to 147%) and a mean coagglutinin cofactor concentration of 89% (min-max, 42% to 165%). These were significantly > the antigen and cofactor concentrations of the grades +2 (n = 5), +3 (n = 3), or +4 (n = 3) dogs. Significant differences were not found when antigen concentrations of the grade +2 dogs (mean, 16%; min-max, 11% to 22%), grade +3 dogs (mean, 13%; 12% to 16%), and grade +4 dogs (mean, 11%; 9% to 12%) were compared with each other, nor were significant differences seen among the coagglutinin cofactor concentrations of the grade +2 dogs (mean, 7%; min-max, 1% to 11%), grade +3 dogs (mean, 6%, 4% to 8%), and grade +4 dogs (mean, 5%; 2% to 9%). Otoplasties of pups whose factor VIII-related antigen and coagglutinin cofactor concentrations were more than 30% required relatively few sponges (mean, 12; minmax, 5 to 19), whereas in most instances, more sponges (mean, 31; 12 to 60) were used during the surgical operations on pups whose antigen and cofactor concentrations were less than 30%.
Retrospective study of four years of carcass condemnation rates for malignant lymphoma in California cows
Authors: Thurmond M. C. , Lapuz G. R. , Farver T. B. , Mandac G. C.
Published: February 2025

A retrospective study was undertaken to examine monthly rates of carcass condemnation for bovine malignant lymphoma in adult dairy cows slaughtered between January 1979 and December 1982, in 2 plants (A and B) in the southern San Joaquin Valley of California. Extremes (mean) of monthly rates for slaughterhouse A were 41 to 100 (65.9) per 10,000 slaughtered and for slaughterhouse B, 39 to 113 (94.1) per 10,000. The overall monthly mean rate was 80 per 10,000 slaughtered.

Equations for long-term trend lines for condemnation rates for slaughterhouses A and B were T = 0.398 + 0.0176t - 0.0002t2 and T = 0.314 + 0.0378t - 0.0007t2, where t = month. A difference in patterns of trends was not apparent, although slaughterhouse A tended to have lower rates of condemnation than did slaughterhouse B.

Seasonal components of trend lines, estimated by time-series analysis, were not consistent between plants, except for the month of August, during which time seasonally adjusted rates were low for both slaughterhouses.

For slaughterhouse A, 2 classic cyclical components were identified—between January 1981 and September 1981 and between September 1981 and September 1982. For slaughterhouse B, the cyclical components were between November 1979 and July 1981 and between July 1981 and August 1982. The later cycle resembled the second cycle of rates from slaughterhouse A.

Rates remained stable through 1979 and then increased steadily for 2.5 years. During the last 6 months of 1982, rates leveled off and perhaps began to decline.