bluuebunny/crossref_metadata_2025 huggingface dataset:
Mucosal and systemic antibody responses to bovine coronavirus structural proteins in experimentally challenge-exposed calves fed low or high amounts of colostral antibodies
Authors: Heckert Robert A. , Saif Linda J. , Mengel Judy P. , Myers Greg W.
Published: January 2024

Ten colostrum-deprived calves were assigned to 1 of 2 treatment groups (5 calves/group), and fed colostrum that had either low (naturally infected cows) or high (immunized cows) antibody titers to bovine coronavirus (bcv). All calves were inoculated orally and intranasally with virulent bcv when they were 24 to 48 hours old and challenge exposed 21 days later. Blood, feces, nasal secretions, tears, saliva, and bronchoalveolar lavage (bal) fluids were collected weekly from each calf for 5 weeks after inoculation. The titers to whole bcv or the relative amounts of isotype-specific antibodies to bcv structural proteins were evaluated in these samples by ELISA or immunoblotting, respectively.

Both pools of colostrum contained primarily IgG1, IgG2, and IgA antibodies to the E2 and E3 bcv proteins. Calves fed the high-titer colostrum had correspondingly higher amounts of passive IgG1 and IgA antibodies to whole bcv and to the E2 and E3 bcv proteins in serum, feces, and bal fluid at postinoculation week 1 than those calves fed low-titer colostrum. Active IgG1, IgA, and IgM antibody responses in serum and active IgA and IgM antibody responses in most mucosal secretions to whole bcv and to the E2 and E3 proteins were lower or delayed in calves fed high-titer colostrum, compared with responses in calves fed low-titer colostrum. In contrast, increased responses to the bcv N protein were observed in all samples (except in serum and bal fluid) in the calves fed high-titer colostrum, compared with calves fed low-titer colostrum. Upon challenge exposure, responses to E2 and E3 bcv proteins in serum and bal fluid were lower in the group fed high-titer colostrum, compared with those in the group fed low-titer colostrum.

Our findings indicate that the level of passive immunity in calves at the time of bcv inoculation can influence the development of active antibody responses in serum, feces, and mucosal secretions to whole bcv and to some bcv proteins individually.
Use of biometry and keratometry for determining optimal power for intraocular lens implants in dogs
Authors: Gaiddon Jacque , Rosolen Serge G. , Steru Lionel , Cook C. S. , Peiffer Robert
Published: January 2024

Axial length and corneal curvature were determined by use of A-scan ultrasonography and keratometry on both eyes of dogs of various breeds, sizes, and ages. Mean axial length was 20.43 ± 1.48 mm; axial length was not related to age or sex, but was significantly greater (P = 0.047) in dogs of larger breeds. Mean corneal curvature was 39.94 ± 2.61 diopters. Dogs of large breeds had significantly (P < 0.001) flatter corneas. Mild, roughly symmetric astigmatism was detected in a majority of dogs. Use of mean values in a theoretic artificial intraocular lens power equation suggests that aphakic dogs require an implant of approximately 40 diopters to achieve emmetropia.
Axial pattern flap based on the caudal auricular artery in dogs
Authors: Smith Mark M. , Payne John T. , Moon Martha L. , Freeman Larry E.
Published: January 2024

An axial pattern flap that was based on the sternocleidomastoideus branches of the caudal auricular artery and vein was developed. Control flaps, which included ligation and division of the caudal auricular artery and vein, were similarly developed on the contralateral aspect of the neck. Mean survival of caudal auricular artery axial pattern flaps (85.2%), compared with control flaps (63.9%), was significantly different (P < 0.05). On the basis of results of this study, an axial pattern flap based on the sternocleidomastoideus branches of the caudal auricular artery and vein may be a source of skin for reconstructive procedures of the head and neck.
Bacterial and mycoplasmal flora of the healthy camelid conjunctival sac
Authors: Gionfriddo J. R. , Rosenbusch R. , Kinyon J. M. , Betts D. M. , Smith T. M.
Published: January 2024

Healthy conjunctival sacs of 88 animals of 3 species of captive camelids (Lamaglama, Lama guanicoe, Lama pacos) and llama-guanaco hybrids were sampled for bacterial and mycoplasmal flora. Mycoplasmas were not isolated from any animal. Eleven genera of bacteria were isolated. The most frequent isolates were Staphyloccus epidermidis and Pseudomonas spp. Nine varieties of Pseudomonas were found, which represented at least 3 Pseudomonas species. Many of the bacterial isolates (especially the pseudomonads) are potential pathogens in the eyes of these camelids.
Characterization of eugonic fermenters group EF-4 by polyacrylamide gel electrophoresis and protein immunoblot analysis
Authors: Hanner Tracy L. , Allen John W. , Robertson-Byers Andrea , Hurley Steven L.
Published: January 2024

Whole-cell lysates and proteinase K-extracted lipopolysaccharide (lps) of 19 strains of the group eugonic fermenter- 4 (ef-4) were analyzed by electrophoresis and protein immunoblotting. These strains were isolated from dog- and cat-bite abscesses in human beings, ferret and human gastric lesions, and cat-lung infections. These strains represent 2 biovar groupings; ef-4a biovars ferment glucose and possess arginine dihydrolase activity, whereas ef-4b biovars do not. Electrophoresis of wholecell lysates could distinguish between these biovars groups. Electrophoresis of lps extracts revealed that all strains of ef-4 possess smooth chemotypes. Two strains of ef-4a reacted weakly in protein immunoblots and revealed distinct lps profiles. These studies suggests that subgroups of ef-4 biovars may exist.
Effects of hemolysis and storage on quantification of hormones in blood samples from dogs, cattle, and horses
Authors: Reimers Thomas J. , Lamb Stephen V. , Bartlett Steven A. , Matamoros Roberto A. , Cowan Robert G. , Engle Jeffrey S.
Published: January 2024

Veterinary diagnostic endocrinology laboratories frequently receive hemolyzed plasma, serum, or blood samples for hormone analyses. However, except for the previously reported harm done by hemolysis to canine insulin, effects of hemolysis on quantification of other clinically important hormones are unknown. Therefore, these studies were designed to evaluate effects of hemolysis on radioimmunoassay of thyroxine, 3,5,3’-triiodothyronine, progesterone, testosterone, estradiol, cortisol, and insulin in equine, bovine, and canine plasma. In the first experiment, hormones were measured in plasma obtained from hemolyzed blood that had been stored for 18 hours. Blood samples were drawn from pregnant cows, male and diestrous female dogs, and male and pregnant female horses. Each sample was divided into 2 equal portions. One portion was ejected 4 times with a syringe through a 20-gauge (dogs, horses) or 22-gauge (cows) hypodermic needle to induce variable degrees of hemolysis. Two subsamples of the blood were taken before the first and after the first, second, and fourth ejections. One sub sample of each pair was stored at 2 to 4 C and the other was stored at 20 to 22 C for 18 to 22 hours before plasma was recovered and stored at —20 C. The second portion of blood from each animal was centrifuged after collection; plasma was recovered and treated similarly as was blood. Concentrations of thyroxine in equine plasma, of 3,5,3’-triiodothyronine, estradiol, and testosterone in equine and canine plasma, and of cortisol in equine plasma were not affected by hemolysis. Storage of bovine blood at either temperature and equine blood at 20 to 22 C caused progesterone concentrations to decrease (P < 0.05); the effect was not enhanced or diminished by hemolysis. Insulin concentration in equine blood decreased (P < 0.05) at both temperatures; this effect was exacerbated by hemolysis. In the second experiment, blood samples from horses and dogs were hemolyzed and plasma was immediately recovered and stored for 18 to 22 hours at 2 to 4 C or 20 to 22 C. Storage of hemolyzed equine plasma did not affect concentrations of progesterone, insulin, or thyroxine at either temperature. Whereas progesterone concentration was not affected in hemolyzed canine plasma, hemolysis decreased (P < 0.05) insulin concentration when plasma was stored at 20 to 22 C. These results emphasize the importance of examining effects of sample collection and handling procedures on hormone stability and the danger of extrapolating results of such studies from one species to another and from one hormone to another.
Effects of exploratory laparotomy on plasma and peritoneal coagulation/fibrinolysis in horses
Authors: Baxter G. M. , Parks A. H. , Prasse K. W.
Published: January 2024

Plasma and peritoneal fluid samples were collected before and after surgery from 6 horses undergoing a ventral midline exploratory laparotomy and from 6 anesthetized control horses. Coagulation/fibrinolytic components measured in the plasma and peritoneal fluid of these horses included the functional activity of antithrombin III, α-2 antiplasmin, plasminogen, and protein C, and the concentrations of fibrinogen and fibrin degradation products. Peritoneal fluid antithrombin III, fibrin degradation products, and plasminogen values were significantly increased after surgery (over time) in principal horses. Compared with control horses, postoperative peritoneal fluid from horses undergoing laparotomy had significantly increased antithrombin-III activity at 12 and 72 hours, α-2 antiplasmin activity at 24 hours, fibrin degradation product concentrations at 6, 12, 24, 72, 96, and 144 hours, plasminogen activity at 6, 12, 24, 48, 72, and 96 hours, and protein-C activity at 12, 24, 72, and 96 hours. There were no significant changes in the peritoneal fibrinogen concentration in principal horses. Plasma plasminogen activity was significantly decreased at 24 hours after surgery in principal horses, compared with controls. Changes were minimal in the remaining plasma coagulation/fibrinolytic components of horses undergoing laparotomy. Plasma and peritoneal fluid values of anesthetized control horses did not change.
Effect of intestinal microflora on digestible energy and fiber digestion in chickens fed a high-fiber diet
Authors: Muramatsu Tatsuo , Kodama Hidenori , Morishita Tohru , Furuse Mitsuhiro , Okumura Jun-ichi
Published: January 2024

The effect of intestinal microflora on digestible energy (de) value and fiber digestion was studied in single-comb White Leghorn chickens fed a low-fiber diet (experiment 1) or a high-fiber diet with low or adequate metabolizable energy (me) value (experiment 2). Fecal energy excretion was calculated from the difference between total energy excretion in urinary and fecal droppings and urinary energy excretion, which was estimated from the energy values for individual urinary nitrogenous compounds extracted with Li2CO3. When the birds were fed the low-fiber diet, no differences in growth, de, or me were observed between germ-free and conventional environments. Of birds fed the high-fiber diet, growth of those in the conventional environment was similar to that of the birds in the germ-free environment at the adequate me value, whereas birds in the conventional environment grew faster than the birds in the germ-free environment at the low me value. Changes in observed dietary me values of the high-fiber diets, being higher in birds in the conventional environment than in birds in the germ-free environment (experiment 2), were almost entirely accounted for by those in dietary de values, most of which was contributed by crude fiber digestion. It was concluded, therefore, that by means of fiber digestion, the intestinal microflora may benefit the host bird by supplying extra energy, which would result in growth promotion, particularly when the bird is deficient in energy.
In vitro responses of distal airways in horses with recurrent airway obstruction
Authors: LeBlanc P. H. , Broadstone R. V. , Derksen F. J. , Robinson N. E.
Published: January 2024

Distal airway segments (id, 3 to 4 mm; length, 5 mm) from 2 groups of horses were isolated and suspended in tissue baths filled with Krebs solution, aerated with 5% CO2 in oxygen and maintained at 37 C. Responses to exogenous acetylcholine, isoproterenol, or electrical field stimulation were compared. Control horses (n = 30) had no history of recurrent airway obstruction, whereas principal horses (n = 15) had recurrent airway obstruction and were studied during an acute episode of airway obstruction. Although the distal airways contracted in response to the cumulative half-logarithmic addition of acetylcholine (10-10M to 10-3M) in both groups, bronchi obtained from principals were less sensitive to acetylcholine than were bronchi obtained from controls. Tetdrodotoxin-sensitive electrical field stimulation-induced contractions were observed in both groups of airways, but the tension achieved in principal bronchi was less than in controls. All electrical field stimulation-induced contractions were abolished by atropine, indicating that the only excitatory innervation of equine distal airways is through the parasympathetic system. To examine the effect of isoproterenol and determine inhibitory innervation, bronchi were precontracted with histamine. Electrical field stimulation did not cause relaxation of precontracted bronchi in either group, thus indicating that distal airways lack inhibitory innervation. Isoproterenol caused similar, dose-dependent relaxation in both groups.
Effects of bacterial infection and castration on prostatic tissue zinc concentration in dogs
Authors: Cowan Laine A. , Barsanti Jeanne A. , Brown John , Jain Anant
Published: January 2024

An Escherichia coli bacterial prostatitis was experimentally induced to determine the effect of bacterial infection on prostatic tissue zinc concentrations in castrated and gonadally intact male dogs. Five of the 22 mixedbreed dogs (group 1) had no culture evidence of infection 2 weeks after the instillation of bacteria into the prostate gland. The remaining 17 infected dogs were allotted to 2 groups; 1 group of dogs was subjected to castration (group ca, 7 dogs), and the other group of dogs was subjected to sham operation (group so, 10 dogs). The groups were divided into groups of dogs with prostatic infection at necropsy (groups ca-i and so-i), and those dogs without prostatic infection at necropsy (groups ca-n and so-n). Urine, prostatic fluid, and prostatic tissue (week 0, 7, ± 12) specimens were obtained for bacteriologic culturing to determine whether prostatic infection was present. Prostatic tissue was obtained at necropsy (week < 6, 7, or 12) for analysis of zinc concentration by atomic absorption spectrophotometry.

The logarithmic mean prostatic tissue zinc concentrations were compared between groups. Group ca had a significantly lower prostatic zinc concentration than all other groups. Zinc concentrations were not statistically different between any of the other groups.

Castration did decrease the prostatic tissue concentration of zinc, a known natural antibacterial factor. However, resistance to infection and resolution of infection were not correlated with prostatic tissue zinc concentrations in this experimental model.
Respiratory tract distribution and bioavailability of spiramycin in calves
Authors: Friis Christian , Erhardsen Elisabeth , Madsen Erik B. , Nielsen Paul , Raun Kirsten
Published: January 2024

Pharmacokinetic determinants of spiramycin and its distribution into the respiratory tract were studied in 2 groups of calves, 4 to 10 weeks old. Group-A calves (n = 4) were used to determine pharmacokinetic variables of spiramycin after iv (15 and 30 mg/kg of body weight) and oral administrations of the drug (30 mg/kg) and to measure distribution of spiramycin into nasal and bronchial secretions. Group-B calves (n = 4) were used to determine distribution of spiramycin into lung tissue and bronchial mucosa. Spiramycin disposition was best described by use of an open 3-compartment model. Mean (± SD) elimination half-life was 28.7 ± 12.3 hours, and steadystate volume of distribution was 23.5 ± 6.0 L/kg. Bioavailability after oral administration was 4 ± 3%. High and persistent concentrations of spiramycin were achieved in the respiratory tract tissues and fluids. Tissue-to-plasma concentration ratio was 58 for lung tissue and 18 for bronchial mucosa at 3 hours after spiramycin administration and 137 and 49, respectively at 24 hours. Secretion-to-plasma concentration ratio was 4 for nasal secretions and 7 for bronchial secretions, and remained almost constant with time. Thus, spiramycin penetrates well into the respiratory tract, although the value in bronchial secretions is lower than that in lung tissues and bronchial mucosa. Calculations indicate that a loading dose of 45 mg/kg, administered iv, followed by a maintenance dose of 20 mg/kg, iv, once daily is required to maintain active concentrations of spiramycin against bovine pathogens in bronchial secretions.
Effect of flurbiprofen on facility of aqueous outflow in the eyes of dogs
Authors: Millichamp Nicholas J. , Dziezyc Joan , Olsen Jory W.
Published: January 2024

Aqueous outflow from cannulated canine eyes was determined, using a constant-pressure perfusion technique. The effect of topically applied flurbiprofen, a cyclo-oxygenase inhibitor, on outflow in eyes with or without neodymium:yttrium aluminum garnet laser-induced inflammation was measured. Flurbiprofen caused decrease in aqueous outflow that was more marked in the inflamed eyes.
Comparative study of colonizing and noncolonizing Campylobacter jejuni
Authors: Meinersmann Richard J. , Rigsby William E. , Stern Norman J. , Kelley Lynda C. , Hill Joseph E. , Doyle Michael P.
Published: January 2024

Campylobacter jejuni A74/O and A74/C are congenic strains. An oral dose of 105 organisms of strain A74/C colonizes chicken intestines. Strain A74/O, from which A74/C is derived, does not colonize the chicken intestines with an oral dose of 105 organisms. In this study, the congenic bacteria were compared to identify possible colonization mechanisms. Differences were not observed in plasmid content or by HindIII, Pst I, Acc I, HincII, Ava I, Ava II, Xba I, and BamHI restriction enzyme digestion of total dna. Transmission electron microscopy of negatively stained samples revealed no differences between the strains. Sections of cecal tissue from nonfed day-of-hatch chicks were cultured with each strain for 2 hours and then examined by light and electron microscopy. Both strains caused necrosis of villus epithelial cells. Immunofluorescent or silver staining revealed strain A74/C located deep in numerous epithelial crypts, but strain A74/O only was present in one sample mixed with sloughed necrotic cells. Similarly, organisms were detected by transmission electron microscopy deep in crypts in tissues cultured with A74/C, but not A74/O. Cells of A74/C detected in crypts did not appear to associate with epithelial cells. The strains did not differ in chemotactic behavior to mucin or fucose.
Changes in linear dimensions of the heart, relative to body weight, as measured by M-mode echocardiography in growing dogs
Authors: Sisson David , Schaeffer David
Published: January 2024

The growth of the heart, relative to body weight, was measured by M-mode echocardiography in dogs during the first year of life. Echocardiographic measurements were obtained from 16 English Pointers at 1, 2, 4, and 8 weeks of age and at 3, 6, 9, and 12 months of age. Left atrial (la), aortic (ao), left and right ventricular internal dimensions, interventricular septal and left ventricular wall thickness measurements increased in curvilinear fashion relative to increasing body weight. Least-squares regression analysis, performed on logarithmically transformed data, was used to develop power-law equations describing the relationship of echocardiographic measurements to body weight. Linear dimensions of the la, ao, left and right ventricular internal dimensions and interventricular septal and left ventricular wall thickness changed proportionally to slightly differing exponential powers of body weight (bw), varying from 0.31 to 0.45 (bw0.31 to bw0.45). Fractional shortening and the la to ao ratio decreased slightly, but significantly, as body weight increased. Indexing echocardiographic measurements to bw1/3 was more appropriate than indexing such measures linearly to body weight, offering a practical method for developing accurate normative graphs or tables for M-mode echocardiographic dimensions in growing dogs.
Effect of endocytic and metabolic inhibitors on the internalization and intracellular growth of Brucella abortus in Vero cells
Authors: Detilleux Philippe G. , Deyoe Billy L. , Cheville Norman F.
Published: January 2024

Uptake, transfer to rough endoplasmic reticulum, and intracellular growth of Brucella abortus were studied in Vero cells treated with endocytic and metabolic inhibitors. Infection of Vero cells was suppressed when inhibitors of energy metabolism (iodoacetate, dinitrophenol), receptor-mediated endocytosis (monodansylcadaverine, amantadine, methylamine), or endosomal acidification (chloroquine, ammonium chloride, monensin) were added to the inoculum. Inhibition was not observed when these drugs were added after the inoculation period. Infection of Vero cells by B abortus was inhibited by dibutyryl-cyclic adenosine monophosphate and Vibrio cholerae enterotoxin, but was stimulated by dibutyryl-cyclic guanosine monophosphate and Escherichia coli heat-stable enterotoxin a. Uptake of B abortus by Vero cells was not prevented by colchicine, but was abolished by cytochalasin B. Uptake of heat-killed B abortus and noninvasive E coli was similar to that of viable brucellae. Intracellular growth of B abortus was not affected by cycloheximide. Results indicate that: B abortus may be internalized by a receptor-mediated phagocytic process; transfer of B abortus from phagosomes to rough endoplasmic reticulum may require endosomal acidification; and replication of B abortus within the rough endoplasmic reticulum may not depend on protein synthesis by the host cell.
Isolation, characterization, and quantitative analysis of ceruloplasmin from horses
Authors: Okumura Masahiro , Fujinaga Toru , Yamashita Kazuto , Tsunoda Nobuo , Mizuno Shinya
Published: January 2024

Ceruloplasmin (Cp) was isolated from fresh equine plasma by precipitation, cellulose chromatography, and improved ion-exchange chromatography. Purified equine Cp is a glycoprotein having a molecular weight of approximately 115,000. In electrophoresis, equine Cp migrated to the α1-globulin region, its isoelectric point was about 4.15 and consisted of about 890 amino acid residues.

Serum Cp concentration was measured by use of the single radial immunodiffusion method. In clinically normal horses, the mean (± sd) serum Cp concentration of newborn foals was 2.87 ± 0.40 mg/ml and that of 3-month-old foals was 5.02 ± 0.92 mg/ml, which was similar to the adult value. It reached a peak of 6.06 ± 0.74 mg/ml in 2-year-old horses. The Cp concentration in mares was not statistically different for the perinatal period, but it decreased immediately before and after delivery.

Concentration of Cp increased at 6 days after im administration of turpentine oil, castration, or jejunojejunostomy in adult horses, and increased to peak values twice as high as baseline values at 7 to 14 days, returning to baseline values at 28 days after treatment.

We concluded that equine serum Cp is an acute-phase reactive protein increased in the intermediary or later phase of acute inflammation.
Efficacy of acyclovir against herpesvirus infection in Quaker parakeets
Authors: Norton Terry M. , Gaskin Jack , Kollias George V. , Homer Bruce , Clark Carl H. , Wilson Robert
Published: January 2024

We evaluated the efficacy of acyclovir against experimentally induced herpesvirus infection (Pacheco's parrot disease) in Quaker parakeets. Thirty-two of 40 birds were challenge-exposed with 0.1 ml of a suspension of herpesvirus (104 median cell culture infective doses [ccid50]) given im. Treatment with acyclovir was started 24 hours later and was continued for 7 days. The birds were allotted to 5 groups of 8 birds each. There was a considerable difference in mortality between groups 1–5. Of 8 birds in each group, 6 died in group 1 (control), 1 died in group 2 (gavage), 3 died in group 3 (low dose, im), 4 died in group 4 (high dose, im), and none died in group 5 (contact controls). There was a significant (P = 0.023) difference in mortality between groups 1 and 2, thus the oral form of acyclovir administered by gavage was the most efficacious therapeutic regimen. Clinical signs and death occurred after discontinuation of acyclovir in groups 2 and 3, whereas the mean time of death for the control group was 6 days after challenge exposure. Herpesvirus was recovered by inoculation of chick embryo cell culture with pooled tissue suspensions from all birds that died. Histologic evidence of herpesvirus infection was found in most birds that died, with the control group having the most severe lesions. Surviving Quaker parakeets were transferred to cages with seronegative Quaker parakeets with no known exposure to herpesvirus. There have been no deaths attributable to herpesvirus infection in a period exceeding 2 years.
Chemoprophylactic effects of milbemycin oxime against larvae of Dirofilaria immitis during prepatent development
Authors: Grieve Robert B. , Frank Glenn R. , Stewart V. Ann , Parsons Jim C. , Belasco Debra L. , Hepler Douglas I.
Published: January 2024

Three studies were conducted to determine the efficacy of milbemycin oxime in the prevention of Dirofilaria immitis infection in dogs. Dogs were given single or multiple experimental inoculations with infective third-stage D immitis larvae and were treated with milbemycin oxime at a target dosage of 0.5 mg/kg of body weight either once or at monthly intervals at various times after inoculation. The compound was effective in preventing infection when 1 dose was administered 30 or 45 days after inoculation. Significant, but incomplete, protection was achieved when single treatments were administered 60 or 90 days after inoculation. Multiple monthly treatments beginning 60 days after inoculation appeared to provide additive effects that resulted in restoration of complete efficacy.
Effects of Superoxide dismutase on injury induced by anoxia and reoxygenation in equine small intestine in vitro
Authors: Johnston Janet K. , Freeman David E. , Gillette Deborah , Soma Lawrence R.
Published: January 2024

Sheets of mucosa from the jejunum of healthy horses were mounted in incubation chambers and bathed with Krebs-Ringer bicarbonate solution. Changes in tissue function and histologic appearance were compared after the following conditions: (1) control conditions for 30 minutes with 95% O2/5% CO2 in the gas phase; (2) same conditions as control, except incubation with superoxide dismutase (300 U/ml) during the last 18 minutes; (3) anoxia for 15 minutes with 95% N2/5% CO2, followed by reoxygenation for 15 minutes; (4) same conditions as 3, except incubation with superoxide dismutase during reoxygenation; and (5) anoxia for 30 minutes. Anoxia reduced the accumulation of radiolabeled l-alanine and caused cell swelling, as indicated by an increase in tissue water and tissue Na contents. Reoxygenation improved the tissue's ability to accumulate l-alanine, but tissue swelling continued after this treatment. Tissue Na content and l-alanine accumulation were restored to control values by reoxygenation with superoxide dismutase in the bathing medium. The grade of structural damage, as indicated by separation of eptihelial cells from villi, was equally severe after all, but control, conditions. Superoxide dismutase had no effect on the tissue control conditions. Results of this study suggest that superoxide radicals are involved in the pathogenesis of reperfusion injury in equine jejunal mucosa and that this may be of clinical importance in cases of small intestinal strangulation obstruction.
Measurement of estrogen receptors in normal and neoplastic lymph node tissue from dogs
Authors: Vicini Donna S. , Ogilvie Gregory K. , Katzenellenbogen John , Carlson Kathryn
Published: January 2024

Estrogen receptors were measured in normal canine lymph nodes and neoplastic tissue from dogs with lymphoma, using a commercially available [3H]estradiol dextran-coated charcoal assay. Using the same assay, estrogen receptors were detected in the positive-control tissues—dog uterus, rat uterus, and lyophilized bovine uterus. Specific binding of [3H]estradiol was not detected in rat skeletal muscle or in any of the canine lymphoid tissues, indicating that the specimens did not contain estrogen receptors.
Colonization of the tonsils of calves with Pasteurella haemolytica
Authors: Frank G. H. , Briggs R. E.
Published: January 2024

Tonsils of 10 calves were inoculated with Pasteurella haemolytica (ph) and the degree of colonization was followed by collecting sequential tonsil, wash specimens. Tonsils were colonized for at least 3 weeks after instillation of ph into the tonsillar sinus. Calves with colonized tonsils responded with serum and nasal secretion antibody responses to ph and to leukotoxin. Pasteurella haemolytica was detected in nasal mucus specimens of 2 calves during the week after inoculation of the tonsils, but all other specimens were culture-negative. Infectious bovine rhinotracheitis virus-induced respiratory tract disease 25 days later did not elicit a population increase of ph in the tonsils, and did not elicit shedding of ph in nasal mucus.
Efficacy of AHR-13268, an antiallergenic compound, in the management of pruritus caused by atopic disease in dogs
Authors: DeBoer Douglas J. , Moriello Karen A. , Pollet Robert A.
Published: January 2024

Twenty-nine pruritic, atopic dogs were entered into a double-blind, placebo-controlled, crossover study to evaluate the efficacy of an investigational antiallergenic compound, AHR-13268. Fourteen dogs were evaluated by a veterinary dermatologist (at intervals) and the owner (daily). Fifteen dogs were evaluated only by the owner. The mean (± se) owner scores for pruritus, erythema, and lesions with placebo treatment (higher score = worse signs) were 3.24 (± 0.12), 2.73 (± 0.12), and 2.61 (± 0.09), respectively. With drug treatment, the corresponding scores were 2.89 (± 0.12), 2.50 (± 0.12), and 2.25 (± 0.09). Scores for pruritus and lesions (but not erythema) were significantly better with drug treatment than with placebo treatment. Investigator scores showed similar trends, but the differences were not great enough to be statistically significant. Overall, 11/29 (38%) owners reported their dogs had moderate or better improvement from drug capsules, and 4/29 dogs (14%) improved on placebo capsules A variety of adverse effects were reported following both drug (9/29 dogs) and placebo (8/29 dogs) capsule administration, but were mild and well tolerated. Results of this study indicate that AHR-13268 has potential for empiric treatment of allergic inhalant dermatitis in some dogs.
Effects of single-dose l-asparaginase on coagulation values in healthy dogs and dogs with lymphoma
Authors: Rogers Kenita S. , Barton Claudia L. , Benson Patricia A. , Green Robert A.
Published: January 2024

Ten healthy dogs and 10 dogs with multicentric lymphoma were given a single dose of l-asparaginase at a rate of 10,000 IU/m2 of body surface. Assessment of concentrations of contributors to the coagulation process and of the ability to coagulate including antithrombin III, one-stage prothrombin time, prothrombin-proconvertin time, activated partial thromboplastin time, plasminogen, fibrinogen, and platelet number were performed prior to drug administration (day 0). These tests were repeated 24 hours (day 1), 48 hours (day 2), and 7 days after treatment with l-asparaginase. Antithrombin-III concentrations were significantly lower in the dogs with lymphoma than in healthy dogs on days 0, 1, 2, and 7; however, with the exception of day 1, mean values remained within normal limits. There was also a difference between the 2 groups in prothrombin/proconvertin values on day 7 and in platelet number on day 2, with the lymphoma group having significantly shorter prothrombin/proconvertin time than healthy dogs, and the difference in platelet numbers being associated with increased counts in the healthy dogs. Data obtained from the healthy dogs and dogs with lymphoma for each coagulation test were pooled for each treatment day (0, 1, 2, and 7), and day-0 values for each coagulation test were compared with data obtained on days 1, 2, and 7. Antithrombin-III concentration on day 7 was significantly lower than on day 0, prothrombin/ proconvertin time on day 1 was significantly longer than on day 0, and fibrinogen concentrations on days 1 and 2 were significantly lower than on day 0. Evidence of clinical hemorrhage or thrombosis was not found in any dog subsequent to l-asparaginase administration. Results of this study suggest that although individual coagulation test results may be altered, a single dose of l-asparaginase does not clinically alter coagulation in either healthy dogs or dogs with multicentric lymphoma.
Detection of Campylobacter upsaliensis in diarrheic dogs and cats, using a selective medium with cefoperazone
Authors: Burnens André P. , Nicolet Jacques
Published: January 2024

Using a newly formulated selective medium containing cefoperazone, we isolated 72 Campylobacter strains in fecal samples from 397 diarrheic dogs and cats. Of these, 39 were thermophilic catalase-negative Campylobacter species. We identified these Campylobacter strains by dna:dna hybridization, using digoxigenin-labeled total genomic dna of 4 Campylobacter reference strains (C jejuni, C coli, C lari, and C upsaliensis) as a probe. The labeling was done with a commercially available kit. We could identify 66 of the 72 Campylobacter isolates to the species level with this method; identification with probes always agreed with conventional test results. Of the 66 identified strains, 33 were C upsaliensis and 33 were C jejuni. Six isolates could not be assigned to a known species with probes or conventional tests. On the basis of our findings, C upsaliensis is more resistant to cefoperazone than to cephalothin, thereby explaining the unexpected recovery of these Campylobacters on cephalosporin-containing media.
Inhibition of equine complement activity by polysulfated glycosaminoglycans
Authors: Rashmir-Raven A. M. , Coyne C. P. , Fenwick B. W. , Gaughan E. M. , Andrews G. A. , DeBowes R. M.
Published: January 2024

The ability of polysulfated glycosaminoglycans (psgag) to inhibit the complement cascade was evaluated. The role of complement in inflammation and infection has been well documented. Inhibition of the complement cascade by psgag could explain why intra-articularly administered psgag diminish diarthrodial joint inflammation and potentiate septic arthritis in horses.

Hemolytic complement testing was performed to evaluate the effect of psgag on the equine classical and alternate pathways of complement, using rabbit erythrocytes as the target cells. Concentration of psgag between 0.2 mg/ml and 0.6 mg/ml significantly (P< 0.05) inhibited equine complement in dose-related fashion. Further increase in complement inhibition was not observed at psgag concentration >0.6 mg/ml. Difference was not apparent in the extent of inhibition of complement from each of the 4 horses tested. Polysulfated glycosaminoglycans appeared to inhibit the classical and alternate complement pathways equally, indicating possible effect on complement components common to both pathways. Heat inactivation of complement function completely inhibited (P<0.01) the hemolytic activity of the serum from all horses.
Evaluation of a subunit vaccine for bovine adenovirus type 3
Authors: York Ian A. , Thorsen Jan
Published: January 2024

The hexon subunit of bovine adenovirus serotype 3 (bav-3) was purified by use of anion-exchange chromatography. A vaccine composed of the purified hexon in immune-stimulating complexes was administered and induced high titer of virus-neutralizing antibody in rabbits and calves.
Fractional excretion of electrolytes in lactating dairy cows
Authors: Fleming S. A. , Hunt E. L. , Brownie C. , Rakes A. , McDaniel B.
Published: January 2024

Samples of serum and urine were obtained simultaneously from 56 healthy lactating cows to determine ranges of fractional excretion (fe) of calcium (Ca), phosphate (PO4), magnesium (Mg), sodium (Na), potassium (K), and chloride (Cl). Samples were obtained at 3 stages of lactation: period 1 = 1 to 7 days, 2 = 83 to 112 days, and 3 = 175 to 197 days. The fe of electrolytes were significantly different among periods 1, 2, and 3 for Ca (P<0.001), PO4 (P< 0.025) and Mg (P<0.025), but were not significantly different for Na, K, and Cl. Least squares mean fe of Ca was lowest in period 1 and not significantly different for periods 2 and 3, whereas mean fe values for PO4 and Mg were highest in period 2 and not significantly different for periods 1 and 3. The mean fe values of Na, K, and Cl did not change with stage of lactation. Age and category of milk production (high, medium, and low) did not influence the FE values of the electrolytes.
Populations of Salmonella typhimurium in internal organs of experimentally infected carrier swine
Authors: Wood Richard L. , Rose Rebecca
Published: January 2024

Experiments were conducted to determine comparative populations of Salmonella typhimurium in the most commonly infected body organs of long-term carrier swine. Naturally farrowed Salmonella-free pigs (n = 58) were orally exposed to S typhimurium when they were 47 days old. Necropsy of 3 to 5 randomly selected pigs was conducted at 3, 7, 10, 14, and 17 days and at 3, 4, 5, 6, 8, 12, 16, 20, 24, and 28 weeks after exposure. Mean populations (log10/g) of S typhimurium in palatine tonsils, ileum, cecum (wall and contents), ascending colon (wall and contents), and mandibular and ileocolic lymph nodes were estimated at each necropsy, using a most-probable-number method of bacteriologic examination. Populations of organisms in cecum and colon were similar to each other throughout the duration of the study. Mean populations (log10/g) associated with cecal and colonic walls decreased from 6.1 and 6.6, respectively, during the first postexposure (pe) week to ≤ 1.67 from pe weeks 4 to 28. Populations (log10/g) associated with cecal and colonic contents decreased from 5.6 and 5.5, respectively, at pe day 3 to 2.5 and 2.7, respectively, at pe week 4, and remained ≤ 2.8 until week 28. Populations (log10/g) associated with intestinal walls and contents were closely correlated during the study. Population (log10/g) in the ileum was ≥ 5.3 from pe days 3 to 17, then varied between 5.4 and -0.4 up to pe week 28. Population (log10/g) of S typhimurium in the tonsils varied from 6.4 to 5.5 up to pe week 5, then decreased to a range of 5.3 to 4.0 until pe week 24, and further decreased to 1.1 at pe week 28. Population (log10/g) in mandibular lymph nodes decreased from 3.5 at pe day 3 to 0.8 at week 8, then ≤ 1.0 up to week 28. In ileocolic lymph nodes, population decreased from 4.4 during the first pe week to ‒0.2 at 8 weeks, then ≤ 1.5 up to week 28. Fecal samples obtained weekly or biweekly throughout the study were 50 to 100% culture-positive (av, 85.4%). Results indicate that the long-term carrier state of S typhimurium in most infected body organs of swine exists mainly at a low, but fairly stable population.
Long-term study of aerobic bacteria of the genital tract in stud dogs
Authors: Bjurström Lena , Linde-Forsberg Catharina
Published: January 2024

The aerobic bacterial flora of the genital tract was characterized in 15 stud dogs in an 18-month study. The dogs represented 4 breeds and were from 3 kennels. Bacterial samples from the prepuce and semen were collected every month, except in connection with matings, when they were collected weekly (464 samples). The dogs that were included all mated at least once during the study. The mean pregnancy rate, litter size, and pup mortality for the bitches with which they had mated were all within normal limits. The most frequent bacteria isolated from the prepuce and semen were Pasteurella multocida, (β-hemolytic streptococci, and Escherichia coli. There was a tendency for breeds to differ in frequency of the most common bacterial species. Bacterial culture yielded no aerobic growth in 14.2% of the preputial samples and 69.8% of the semen samples. Bacteria were transferred between dog and bitch at mating. In this study of healthy breeding dogs, neither the fertility of the dog nor that of the bitch was affected by the bacteria transferred.
Response of Pasteurella haemolytica to erythromycin and dexamethasone in calves with established infection
Authors: Clarke Cyril R. , Barron Selwyn J. , Ayalew Sahlu , Burrows George E.
Published: January 2024

A subcutaneous soft tissue infection model in calves was used to study the in vivo response of Pasteurella haemolytica to erythromycin and dexamethasone. Two tissue chambers were implanted sc in each of 12 calves. At 45 days after implantation, all tissue chambers were inoculated with an erythromycin-sensitive strain of P haemolytica. Starting 24 hours after inoculation, calves were allotted to 4 groups of equal size and a 2 × 2-factorial arrangement of treatments was applied: 3 calves were given erythromycin (30 mg/kg of body weight, im, for 5 days), 3 calves were given dexamethasone(0.05 mg/kg, im, for 2 days), 3 calves were given erythromycin and dexamethasone, and the remaining calves served as nontreated controls. Chamber fluids were tested daily, and the response to treatment was measured. Neither erythromycin nor dexamethasone affected viability or growth of bacteria within tissue chambers. Dexamethasone had no effect on the influx of neutrophils into infected chambers. Despite repeated administration of a high dose of erythromycin and attainment of adequate concentration in serum, erythromycin concentration in chamber fluids did not exceed the minimal inhibitory concentration established in vitro. These results indicate that the clinical efficacy of erythromycin against P haemolytica sequestered in consolidated pneumonic lesions may not be well correlated with predictions based on serum pharmacokinetic and in vitro susceptibility data.
Impact of bovine somatotropin administration beginning at day 70 of lactation on serum metabolites, milk constituents, and production in cows previously exposed to exogenous somatotropin
Authors: Lean Ian J. , Baldwin R. Lee , Troutt H. Fred , Bruss Michael L. , Galland John C. , Farver Thomas B. , Rostami Jeffrey , Weaver Leon D. , Holmberg Charles A.
Published: January 2024

Metabolic and production responses are reported for 72 cows treated with bovine somatotropin (bst) for 30 days starting at day 70 of lactation. Of these 72 cows, 48 had been exposed in the preceding lactation to long-term treatment with bst at 3 dosages and 24 (controls) had not been given bst. Approximately half of the cows in each group were parity-2 cows, the rest were older. Comparisons between groups were made separately for parity-2, and older cows.

Analyses, using pretreatment values of each variable as a covariate, indicated that older cows, but not parity-2 cows, significantly (P < 0.05) increased milk production during treatment. Parity-2 cows, however, had a significantly higher milk fat percentage than controls following treatment. Cows treated with 51.6 or 86 mg bst/d in both parity groups had significantly higher serum-free fatty acids than controls. Estimated net energy balances were significantly lower for older treated cows, but did not significantly differ from controls for parity-2 treated cows. Older cows in the 86 mg of bst/d group tended to have higher concentrations of blood glucose than did older control-group cows. Treatment with bst did not significantly increase serum ketone concentrations in any group of animals, and none of the cows developed clinical ketosis during this period.

Estimated net energy balance (eneb) during treatment was a significant (P < 0.05) covariate for free fatty acid concentrations in older cows and for milk fat percentage in parity-2 cows. Covariate adjusted analyses, using eneb during treatment as a covariate, indicated that lipolytic stimuli already acting may be enhanced by treatment with bst, but a negative energy balance was not a necessary precondition for free fatty acid concentrations to increase following somatotropin treatment. Similarly, milk fat percentages for parity-2 treated cows were significantly (P < 0.05) higher during treatment than controls when eneb during treatment was used as a covariate.

Increased milk fat concentrations in parity-2 treated cows were not associated with significant increases in the ratio of C18:C4-10 milk fatty acids, indicating that increased milk fat resulted from either an increase in incorporation of C18 fatty acids into milk fat coupled with an increase in de novo mammary synthesis of C4-10 milk fatty acids or an increase in C12-16 fatty acids that may arise either from increased tissue mobilization, from diet, or from de novo mammary synthesis.
Culture and initial characterization of the secretory response of neoplastic cat mast cells
Authors: Mohr F. Charles , Dunston Sheryl K.
Published: January 2024

Mast cells isolated from feline splenic mastocytomas were cultured to study their structural and functional properties. Isolated cells from various cats were grown as monolayer cultures for a mean of 56 days (range, 30 to 76 days). Cat mast cells released allergic mediators in response to compound 48/80, anti-cat serum antibodies, and concanavalin A. On the basis of the finding that secretion from cat mast cells was stimulated by anti-cat serum antibodies and concanavalin A, these cells contain surface-bound immunoglobulins. The presence of mast cell-sensitizing antibodies has been suspected in cats, but never before directly demonstrated. Cultured cat mast cells have cytochemical and functional characteristics common to connective tissue-type mast cells and provide one of the few non-rodent models of cultured cells for the study of this type of mast cell.