bluuebunny/crossref_metadata_2025 huggingface dataset:
Phagocytosis, bactericidal activity, and oxidative metabolism of milk neutrophils from dairy cows fed selenium-supplemented and selenium-deficient diets
Authors: Grasso P. J. , Scholz R. W. , Erskine R. J. , Eberhart R. J.
Published: January 2024

Six primiparous Holstein cows were fed a Se-deficient diet, beginning at least 90 days before their first calving, and 6 other primiparous cows were given the same diet plus a supplement of 2 mg of Se/cow/d as sodium selenite. All cows were fed their diets for the duration of the experimental period. One uninfected quarter of each cow was injected with 25 μg of Escherichia coli endotoxin at postpartum week 5. Leukocytes were isolated by centrifugation from milk collected at postinjection hour 16. Isolated cells were 92 ± 3% neutrophils and were incubated with Staphylococcus aureus or E coli in a 1:300 ratio. Phagocytosis and intracellular killing by neutrophils were assessed after 0, 30, 60, and 90 minutes by a fluorochrome assay, using acridine orange. Viability of neutrophils was assessed by use of trypan blue. Superoxide anion production and hydrogen peroxide production by neutrophils also were determined.

Cows fed Se-deficient diets had significantly (P < 0.05) lower blood Se concentration and blood glutathione peroxidase activity than cows fed Se-supplemented diets. Selenium status had no effect on the phagocytic capacity of neutrophils. Neutrophils obtained from cows fed Se-supplemented diets killed a significantly (P < 0.05) higher percentage of ingested bacteria than did neutrophils from cows fed the Se-deficient diet. Viability was significantly (P < 0.05) reduced by incubation with S aureus in neutrophils from both groups of cows, with neutrophils from Se-deficient cows having lower viability. Superoxide anion production did not differ significantly between neutrophils from the 2 groups, but extracellular hydrogen peroxide concentration was significantly (P < 0.05) higher in neutrophils harvested from milk of cows fed the Se-deficient diet.
Platelet aggregation studies in dogs with acute Ehrlichia platys infection
Authors: Gaunt Stephen D. , Baker Dale C. , Babin Shirley S.
Published: January 2024

Ten adult dogs (5 Beagles and 5 mixed-breed dogs) were inoculated IV with canine platelets containing Ehrlichia platys. Inclusions and morulae of E platys developed in platelets of infected dogs at 10 to 14 days after inoculation, followed by marked thrombocytopenia at 14 to 21 days. Parasitemia and marked thrombocytopenia recurred at 24 to 28 days after inoculation. Increased numbers of megakaryocytes were observed in marrow aspirate smears from infected dogs, indicative of regenerative thrombocytopenia. Prior to infection, platelet-rich plasma from these dogs was determined to have similar aggregatory response to arachidonate. After infection with E platys, the aggregatory response of platelet-rich plasma to collagen or 3 dilutions of adenosine diphosphate was evaluated. A statistically significant (P < 0.05) inhibition of platelet aggregatory response to the lowest dilution of adenosine diphosphate was detected for mixed-breed dogs, whereas aggregation responses were unchanged in Beagles. Results indicate that platelet activation may occur in dogs with acute ehrlichial infection.
Influence of induced cholestasis on pharmacokinetics of digoxin and digitoxin in dogs
Authors: Miyazawa Y. , Sato T. , Kobayashi K. , Akahori F. , Suzuki T. , Miyashita H.
Published: January 2024

Dogs with ligated common bile ducts were used to determine effects of cholestasis on pharmacokinetics of digoxin and digitoxin. Forty-three dogs were assigned to: group 1—sham-operated controls (n = 13); group 2—dogs with ligated common bile duct (n = 17); group 38—dogs given phenobarbital for 2 weeks before common bile duct was ligated (n = 11); or group 4—dogs with an induced biliary fistula (n = 2). Digoxin (group A) or digitoxin (group B) was given as single iv injections, and digitalis concentration in plasma was measured by radioimmunoassay.

In 18 dogs given digoxin, differences in plasma digoxin concentrations among groups 1A to 3A were not significant (P > 0.1). Plasma elimination rate of digoxin was delayed in group 2A. Group-3A dogs had a shortened β phase half-life (t½(β)) and a decreased distribution volume.

In 25 dogs given digitoxin, group-2B dogs maintained a significantly higher plasma digitoxin concentration (P < 0.01) and had a significantly longer t½(β) than did dogs in groups 1B and 3B (P < 0.05). In group-3B dogs, plasma digitoxin concentration was decreased and t½(β)) of digitoxin was shortened. In 10 group-B dogs given 3H-digitoxin (groups 1B, 2B, and 4B), the excretion of total radioactivity in urine and bile was 15 to 20 and 7% of the dose, respectively in the first 24 hours. Most radioactivity in urine and bile was a dichloromethane-unextractable fraction. In group-3B dogs, the urinary excretion was 35% of the dose, and the dichloromethane-unextractable fraction was greater than those in other groups.

Seemingly, the status of the liver affected pharmacokinetics of digoxin and digitoxin. However, the influence of induced cholestasis on the pharmacokinetics of digitoxin appeared to be greater than that of digoxin in dogs.
Reproductive consequences of deficiency of uridine monophosphate synthase in Holstein cattle
Authors: Shanks Roger D.
Published: January 2024

Cattle heterozygous for deficiency of uridine monophosphate synthase required more breeding services per calving when mated to other heterozygotes than did matings of normal cattle. Gestation length, number of breeding services per calving, and days from breeding to pregnancy examination were monitored on 759 complete gestations, 76 false-positive pregnancy diagnoses, 14 false-negative pregnancy diagnoses, and 413 negative pregnancy diagnoses in a dairy herd between 1983 and 1987. For complete gestations, 15 heterozygote × heterozygote matings required 3.13 ± 0.37 breeding services per calving, which was significantly more than the 2.05 ± 0.05 breeding services required for normal × normal matings; gestation length and days from breeding to pregnancy examination were similar between mating types. For false-positive pregnancy diagnoses, females diagnosed pregnant, but subsequently found not to be pregnant, 5 heterozygote × heterozygote matings averaged 51 ± 23 days of gestation, which was less than the 93 ± 6 days required for 71 normal matings; services and days from breeding to pregnancy examination were similar between mating types. All false-negative pregnancy diagnoses, females diagnosed not pregnant but later found to be pregnant, were made on cattle with normal matings. For negative pregnancy diagnoses, heterozygous matings averaged 0.3 more breeding services per examination than normal matings.
Identification of gonadal steroid receptors in meningiomas from dogs and cats
Authors: Speciale John , Koffman Boyd M. , Bashirelahi Nasir , Steinberg Sheldon A.
Published: January 2024

Cytosolic assay was used to detect gonadal steroid receptors in brain tumor tissue from 6 dogs and 2 cats. For 4 samples, the maximal number of binding sites and the equilibrium dissociation constant were calculated, using Scatchard analysis. The concentration of receptor protein that was discovered was similar to that detected in hormone-sensitive tumors.
Effect of bovine fibroblast interferon on rhinovirus infection in calves
Authors: Rosenquist Bruce D. , Allen Gary K.
Published: January 2024

The prophylactic/therapeutic activity of natural bovine fibroblast interferon (BoF-ifn) against bovine rhinovirus infection in calves was assessed. Six calves were each given 8 intranasal inoculations of partially purified BoF-ifn (3.25 × 105 U at 8 am, 11 am, 5 pm, and 8 pm on day 1 and 8 am, 11 am, 2 pm, and 5pm on day 2), and 6 calves were given placebo. All calves were challenge exposed with 105.1 TCID50) of bovine rhinovirus after the first 2 treatments (6 hours after the first ifn or placebo treatment). Nasal excretion of rhinovirus, ifn concentration in the nasal secretions, and nasal secretion and serum rhinovirus antibodies were measured before and at selected times after calves were inoculated. Interferon-treated calves excreted rhinovirus in their nasal secretions in lesser amounts (mean value, 0.84 log10 TCID50/ml vs 1.58 log10 TCID50/ml on postchallenge exposure days 1 and 2; (P < 0.05) and for a shorter duration (P < 0.05) than did placebo-treated calves. No calves developed clinical signs of respiratory tract illness. Rhinovirus antibody titer was not significantly different between ifn- and placebo-treated calves.
Necrotic oophoritis in heifers vaccinated intravenously with infectious bovine rhinotracheitis virus vaccine during estrus
Authors: Smith Paul C. , Nusbaum K. E. , Kwapien R. P. , Stringfellow D. A. , Driggers K.
Published: January 2024

Twenty-two Hereford heifers were injected im with prostaglandin F2αa, 11 days apart to synchronize estrous cycles. Twelve of 14 heifers that had signs of estrus were inoculated iv with 1 of 3 modified-live infectious bovine rhinotracheitis virus vaccines, and 2 were assigned to a nonvaccinated control group. Also, 6 of the 8 anestrous heifers were inoculated iv with 1 of the 3 vaccines on the fourth day after the last prostaglandin injection and the other 2 were assigned to the nonvaccinated group. Vaccine virus was isolated from the blood and nasal and vaginal secretions from the vaccinated heifers on postvaccination days 4, 7, and 9. On postvaccination day 9, all heifers were ovariectomized and ovarian tissues were processed for virus isolation and histologic examination. Vaccine virus was isolated from ovarian tissues of some heifers in each of the vaccine groups. Necrotic oophoritis characterized by multifocal areas of ovarian tissue necrosis, hemorrhage, and mononuclear lymphocytic infiltration was observed. The corpora lutea and surrounding ovarian tissues taken from vaccinated heifers in each group had varying amounts of necrotic and inflammatory change, but the changes appeared to be more severe in 1 group than in the other 2. Virus also was isolated from 2 of the controls; these heifers apparently became infected with vaccine virus that had been excreted from the vaccinated animals.
Development of wheat-sensitive enteropathy in Irish Setters: Morphologic changes
Authors: Hall Edward J. , Batt Roger M.
Published: January 2024

Morphologic changes in the small intestine were investigated during development of naturally acquired wheat-sensitive enteropathy in Irish Setters. To distinguish underlying morphologic abnormalities from non-specific effects of intestinal damage, progeny of affected dogs reared on a normal wheat-containing diet were compared with their own littermates reared on a cereal-free diet and with age-matched clinically normal Irish Setters fed the same wheat-containing diet. Peroral jejunal biopsy specimens were taken sequentially between 4 months and 1 year of age. At 4 months of age, there were no differences in villus height, comparing the 3 groups, but increased numbers of intraepithelial lymphocytes and goblet cells were already present in biopsy specimens from the affected Irish Setters fed wheat. Dietary wheat resulted in a progressive reduction in villus height in the jejunum of affected Irish Setters from 6 months onward. Underlying morphologic abnormalities were not found, and the characteristic morphologic changes of this enteropathy were secondary to the presence of dietary wheat. However, development of partial villus atrophy was preceded by increased numbers of intraepithelial lymphocytes and goblet cells.
Comparison of dna:dna homology and enzymatic activity between Pasteurella haemolytica and related species
Authors: Bingham Douglas P. , Moore Rebecca , Richards Alan B.
Published: January 2024

A commercially available microbiological identification system and dna:dna hybridization were used to determine relationships between and within serovars 1-13 of Pasteurella haemolytica, and between P haemolytica and P multocida and 4 species of Actinobacillus. All serovars of P haemolytica that belonged to biovar A were related with mean dna homology of 78%, whereas all serovars of P haemolytica that belonged to biovar T were related to each other with mean dna homology of 90%. The dna:dna hybridization between strains of biovars A and T ranged from 3 to 13%, indicating little or no genetic relationship between the 2 biovars of P haemolytica. The dna homology between all serovars of P haemolytica and other species of non-P haemolytica bacteria tested (P multocida and actinobacilli) was < 14%, suggestive of essentially no genetic relationship of P haemolytica with the atcc reference strains of the genus Pasteurella or the genus Actinobacillus.

Enzymatic differences were observed between P haemolytica and the other non-P haemolytica bacteria tested; however, the microbiological identification system that uses enzymatic reactions could not distinguish among biovars of P haemolytica. Results of this research support other data that suggest that biovars A and T of P haemolytica should be classified as separate species, but do not support the inclusion of either biovar A or T within the genus Actinobacillus.
Effects of teat cistern mural biopsy and teatoscopy stab versus longitudinal incision with or without tube implant on incisional healing in lactating dairy cattle
Authors: Tulleners Eric , Hamir Amir
Published: January 2024

Effects of teat cistern mural biopsy and full-thickness stab and longitudinal incisional healing were evaluated experimentally on clinically normal teats in 12 lactating dairy cattle. Each teat on each cow was assigned by Latin-square design to 1 of 4 surgical interventions: (I) teatoscopy only; (II) teatoscopy, stab incision, and mural biopsy; (III) longitudinal incision and mural biopsy; and (IV) longitudinal incision, mural biopsy, and tube implantation.

Teatoscopy was done with a 4-mm od arthroscope introduced through the teat canal and attached to a television camera. Teatoscopy was quicker to perform and provided a more detailed videotaped examination of the teat and gland cistern, compared with gross inspection through a longitudinal incision. In intervention-II cows, the Ferris-Smith biopsy instrument jaws introduced through a longitudinal 1-cm midteat stab incision were easy to visualize and manipulate accurately. Stab incisions closed with only 1 or 2 skin sutures healed without complications in all 12 teats. On palpation, stab incisions were significantly (P < 0.01) less thick than longitudinal incisions at 8 weeks and were microscopically indistinguishable from the normal tissue. However, in 24 teatoscopically examined teats, 9 (38%) had microscopic evidence of teat canal injury and 12 (50%) of the quarters developed mastitis. This was attributed to trauma resulting from introduction of the arthroscope through the teat canal.

Intervention III yielded satisfactory results with the least complications. All 12 longitudinal incisions healed by primary intention, and all teats remained patent. Mastitis developed in 4 (33%) quarters.

Intervention IV caused considerable complications associated with the tube implant and no improvement in biopsy site healing, compared with interventions II and III. Eleven longitudinal incisions healed by primary intention. One incision dehisced, 2 (17%) tube implants dislodged, 2 (17%) became obstructed proximally, and irritations of the mucous membrane developed in 2 teats proximally and in 6 teats distally. Mastitis developed in 6 (50%) quarters.

Longitudinal incisions healed with moderate submucosal fibrosis. All sutured incisions had multifocal microgranulomata in which suture material was in various stages of degradation. At 8 weeks, localized teat wall thickening could be detected at incisional and biopsy sites, but did not obstruct milk flow.

Excessive granulation tissue was at the biopsy sites (72 total) at 2 weeks, and at this time, the sites were partially covered by metaplastic squamous epithelium. However, by 8 weeks, 71 (98%) of the areas were replaced by fibrous tissue with minimal protrusion into the teat cistern.
Nephrotomography and ultrasonography for the localization of hyperfunctioning adrenocortical tumors in dogs
Authors: Voorhout George , Rijnberk Ad , Sjollema Bart E. , van den Ingh Ted S. G. A. M.
Published: January 2024

Nephrotomography and ultrasonography were used in 11 dogs with hyperadrenocorticism to assess the value of these techniques for the localization of biochemically diagnosed hyperfunctioning adrenocortical tumors. Both techniques enabled accurate localization of a unilateral adrenal mass in each of the dogs. Cross-sectional diameters of the masses ranged from 1 to 4 cm. In 1 dog, expansion of tumor into the caudal vena cava was revealed by caudal venacavography and ultrasonography. Mineralization in the tumor mass in 2 dogs was easily recognized by nephrotomography, but not by ultrasonography.

Paracostal laparotomy confirmed the presence of an adrenocortical tumor in each dog, and expansion of tumor into the caudal vena cava in 1 dog. Cross-sectional diameters of the tumors ranged from 1.2 to 4.5 cm and corresponded well with cross-sectional measurements by nephrotomography and ultrasonography.

It was concluded that nephrotomography and ultrasonography have similar diagnostic accuracies for the detection and localization of hyperfunctioning adrenocortical tumors.
Determination of macrophage chemotaxis to atherosclerotic plaque extract in domestic turkeys with hypertension
Authors: Johnson Patricia D. , Klesius P. H. , Krista L. M.
Published: January 2024

The chemotactic activity of turkey peritoneal macrophages in response to an atherosclerotic plaque extract from a hypertensive strain of turkeys was determined. Atherosclerotic plaque extract stimulated macrophage chemotaxis, whereas normal aortic extract did not stimulate macrophage chemotaxis. However, differences were not revealed by sodium dodecyl sulfate-polyacrylamide gel electrophoretic analysis of extracts of atherosclerotic plaque and normal aorta. Chemotactic activity was diminished with pronase treatment, suggesting the chemoattractant is a protein. Seemingly, atherosclerotic plaque of turkeys contains a macrophage chemotaxin.
Histologic and immunochemical study of the pathogenesis of heartwater (Cowdria ruminantium infection) in goats and mice
Authors: Brown Corrie C. , Skowronek Anthony J.
Published: January 2024

Eleven adult goats and 32 adult outbred mice were inoculated iv with Cowdria ruminantium-infected blood (Kwanyanga isolate), monitored clinically, then serially euthanatized. Predominant clinical signs of disease in goats were depression, head tremors, seizures, and dyspnea. In mice, dyspnea and depression were the only clinical signs of disease noticed. Tissues were examined histologically and immunohistochemically for C ruminantium colonies or antigen. In goats, C ruminantium was detected only in endothelial cells of the brain, even though gross and microscopic lesions were confined to the thorax. In mice, C ruminantium was detected only in endothelial cells of the heart and lungs.
Modulation of arachidonic acid metabolism by bovine alveolar macrophages exposed to interferons and lipopolysaccharide
Authors: O'Sullivan M. G. , Fleisher L. N. , Olson N. C. , MacLachlan N. J. , Brown T. T.
Published: January 2024

Stimulation of bovine alveolar macrophages with calcium ionophore A23187 resulted in marked production of leukotriene (lt)B4 and a lesser increase in thromboxane (tx)B2, whereas opsonized zymosan (opz) resulted in production of txb2 and relatively small increases in ltb4 and prostaglandin (pg)F2α. Alveolar macrophages incubated with recombinant bovine interferon-γ or lipopolysaccharide, and subsequently stimulated with A23187 or opz, had altered arachidonic acid metabolism, producing markedly increased amounts of txb2 and pgf2α, and slightly increased ltb4. Incubation of alveolar macrophages with lipopolysaccharide had a more profound effect on the increased amounts of txb2 and pgf2α, observed in response to stimulation with A23187 or opz, than did incubation with interferon-γ. Alveolar macrophages incubated with recombinant bovine interferon-α1-1 also produced slightly increased amounts of ltb4 when stimulated with A23187 or opz. Altered arachidonic acid metabolism by alveolar macrophages exposed to interferons and lipopolysaccharide may contribute to the development of pulmonary inflammation, such as in the early stages of bacterial pneumonia following viral infections that induce interferon production.
Experimental infection of the white-footed mouse with Borrelia burgdorferi
Authors: Wright Scott D. , Nielsen Svend W.
Published: January 2024

Laboratory raised white-footed mice (Peromyscus leucopus) were inoculated experimentally with live spirochetes (Borrelia burgdorferi), the etiologic agent of Lyme disease (borreliosis). Prior to inoculation, mouse sera were tested with an indirect fluorescent antibody test, and all mice were seronegative. All inoculated mice seroconverted. In tick transmission studies, immature stages of Ixodes dammini and Dermacentor variabilis attached and fed to repletion on mice, but only I dammini transferred spirochetes to uninfected mice. Mice were susceptible to oral infection and transmitted infection to each other through direct contact. Infection did not affect reproduction or development of young born from infected dams, nor did spirochetes appear in the tissues of neonates. Borrelia burgdorferi spirochetes were identified in the kidneys, liver, and spleen of infected mice by the use of the modified Steiner silver stain and a tissue indirect fluorescent antibody test. Spirochetes also were isolated in culture of the heart blood of 1 mouse. Regardless of the source of infection, no mice developed clinical signs or had any pathologic change resulting from infection. Spirochetes were always observed extracellularly within interstitial spaces. Antibody titers persisted for over 4 months in some mice and spirochetes were found in the tissues of 1 mouse that had been infected 1 year earlier.
Efficacy of clorsulon for the treatment of experimentally induced infections of Fasciola hepatica in goats
Authors: Sundlof Stephen F. , Bliss Ernest L. , Greiner Ellis C. , Tran Thang Q. , Wertenberger Mary A.
Published: January 2024

A dose titration study was undertaken to determine the efficacy of clorsulon against the adult stage of Fasciola hepatica in goats. Thirty-nine goats were experimentally infected with metacercariae of F hepatica. At 14 weeks after infection, each goat was assigned randomly to 1 of 5 groups. Goats in groups 1 to 4 received a single oral administration of clorsulon at dosages of 3.5, 7, 11, and 15 mg/kg of body weight, respectively. The fifth group of goats (control group) was infected with F hepatica, but were not treated with clorsulon. Postmortem examination of goats at 3 weeks after treatment revealed mean reductions in numbers of flukes of 83, 98, 99, and 100% for groups 1 to 4, respectively. Mean percentage of reduction in eggs following treatment of groups was 82, 98, 100, and 100%, respectively.

The clinical effects of clorsulon in 24 goats that were not infected with F hepatica were studied. Goats in groups 1 to 3 received a single oral administration of clorsulon at dosages of 7, 21, and 35 mg/kg, respectively, every other day for a total of 3 doses/goat. Group-4 goats (control group) received a vehicle placebo. Goats in group 3 were subject to postmortem examination at 14 days after dosing. Abnormal signs or lesions that could be attributed to clorsulon were not found in any goat.
von Willebrand factor in lysates of washed canine platelets
Authors: Parker Michael T. , Turrentine Mark A. , Johnson Gary S.
Published: January 2024

Canine and human platelets (washed 4 times in a solution containing edta, prostaglandin E1, and theophylline to prevent release of agranule constituents) were lysed by being frozen and thawed in the presence of detergent. Radioelectroimmunoassay for von Willebrand factor (vWf) in 5 human platelet lysates produced precipitin rockets, shaped like those produced from vWf in plasma from healthy human beings, and indicated that the mean von Willebrand factor antigen (vWf:Ag) content in platelets from healthy human beings was 526 ± 87 human U/ 1012 platelets. Radioelectroimmunoassay for vWf in platelet lysates from 17 healthy dogs with normal plasma vWf:Ag concentration produced precipitin rockets that looked different from those produced from canine plasma and indicated vWfAg content of 59 ± 35 canine U/1012 platelets. Inclusion of protease inhibitors in the lysing solution did not normalize the appearance of the precipitin rockets or substantially alter the measured platelet content of vWf:Ag. The array of vWf multimers revealed by sodium dodecyl sulfate-agarose gel electrophoresis of canine platelet lysates had a distinct appearance that differed from that of vWf in canine or human plasma and platelets; the intensity of the canine platelet vWf multimer bands was skewed, with relatively greater density in the lower molecular weight region and faint or undetectable multimer bands in the higher molecular weight region. Electrophoretograms with visible multimers in the high molecular weight region had vWf components that had higher molecular weight than did any vWf components in canine plasma. Radioelectroimmunoassay for fibronectin in these same canine platelet lysates indicated that the fibronectin content in platelets was 2.89 ± 1.10 mg/1012 platelets. An Airedale Terrier with type-I von Willebrand disease (vWd), but lacking clinical signs of vWd, had normal platelet content of vWf:Ag (28 ± 12 canine U/1012 platelets), whereas a German Shorthaired Pointer with moderately severe type-II vWd and a mildly affected Doberman Pinscher with type-I vWd had only a trace or undetectable amounts of vWf:Ag in their platelets. The concentration of vWf: Ag in platelet lysates from the Doberman Pinscher with vWd remained undetectable when the platelets were isolated from the Doberman Pinscher's blood mixed with citrated plasma from dogs with normal plasma vWf:Ag concentration. In all 3 dogs with vWd, platelet fibronectin content was within the normal range.
Cardiopulmonary function values before and after heartworm removal in dogs with caval syndrome
Authors: Kitagawa H. , Sasaki Y. , Ishihara K. , Kawakami M.
Published: January 2024

Cardiopulmonary function values were determined before and after surgical removal of adult heartworms in 25 dogs with spontaneous and 4 dogs with drug-induced caval syndrome (cs). Fifteen dogs with spontaneous cs (recovery group) and 4 dogs with drug-induced cs (drug-induced cs group) recovered after removal, and 10 dogs with spontaneous cs were euthanatized or died (nonsurviving group). Before heartworm removal, injected radiographic contrast medium was regurgitated from the right ventricle to the right atrium. Mean pulmonary arterial pressure and total pulmonary resistance were not statistically different between the recovery and nonsurviving groups of dogs, but the end-diastolic right ventricular pressure (mean ± sd, 6.9 ±9.1 mm of Hg) and the a (8.7 ± 9.2 mm of Hg)- and v (6.3 ± 8.5 mm of Hg)-waves of the right atrial pressure curve in the recovery group were less, respectively, than the end-diastolic right ventricular pressure (17.3 ± 6.0 mm of Hg) and the a (15.8 ± 6.1 mm of Hg)- and v (21.4 ± 6.9 mm of Hg)-waves in dogs of the nonsurviving group. After heartworm removal, contrast medium regurgitation disappeared, and cardiac output of the right ventricle increased in dogs of the recovery (from 2.08 ± 0.72 to 2.38 ± 0.68 L/min; P < 0.05) and drug-induced cs (from 1.42 ± 0.19 to 1.88 ± 0.26 L/ min, P < 0.05) groups. However, regurgitation remained, and cardiac output did not increase in some dogs of the nonsurviving group. Mean pulmonary arterial pressure decreased significantly (from 37.7 ± 18.3 mm of Hg to 32.0 ± 16.1 mm of Hg; P < 0.01) at 1 week after heart-worm removal in dogs of the recovery group, but not in those of the nonsurviving group. Total pulmonary resistance (from 12,612 ± 7,670 dynes·sec·cm-5·kg of body weight to 9,776 ± 6,089 dynes·sec·cm-5·kg; P < 0.01) and right atrial pressure (a-wave: from 8.7 ± 9.2 mm of Hg to 4.1 ± 5.6 mm of Hg; v-wave: from 6.3 ± 8.5 mm of Hg to 2.1 ± 4.6 mm of Hg) decreased after heartworm removal in dogs of the recovery group. Total pulmonary resistance (from 20,309 ± 9,682 dynes·sec·cm-5·kg to 15,970 ± 6,798 dynes·sec·cm-5·kg; P < 0.05) and right atrial pressure (a-wave: from 15.8 ± 6.1 mm of Hg to 10.1 ± 6.3 mm of Hg; v-wave: from 21.4 ± 6.9 mm of Hg to 11.1 ± 3.7 mm of Hg) also decreased in dogs of the nonsurviving group. However, pressures in the right side of the heart and total pulmonary resistance after heart-worm removal were greater in dogs of the nonsurviving group than in dogs of the recovery group. At necropsy, pulmonary arterial emboli containing dead heartworms were found in almost all dogs with spontaneous cs, but not in dogs with drug-induced cs. The severity of pulmonary arterial embolism correlated significantly with mean pulmonary arterial pressure before (r = 0.710; P < 0.01) and 1 week after (r = 0.728; P < 0.01) heartworm removal.
Measurement of anal and genitoanal reflexes in cats
Authors: Cook James R. , Oliver John E. , Purinton Paul T.
Published: January 2024

Noninvasive determination of anal and genitoanal reflexes was evaluated in clinically normal cats. Thirty adult mixed-breed cats (15 sexually intact or castrated males, 15 sexually intact or spayed females) were sedated by iv administration of ketamine, acetylpromazine, and atropine. Anal reflexes were recorded from the anal sphincter muscle after ipsilateral and contralateral electrical stimulation of the perineal skin. Genitoanal reflexes were recorded from the anal sphincter muscle after electrical stimulation of the penis or clitoris. An anal sphincter response to tibial nerve stimulation was attempted.

Anal reflexes from ipsilateral and contralateral stimulations and a genitoanal reflex were detected in all cats. Anal sphincter responses to tibial nerve stimulation were inconsistent (4/30) and were not included in any analyses. Anal reflexes had response latencies of 7.5 to 12.0 ms (ipsilateral stimulation) and 6.5 to 13 ms (contralateral stimulation). Genitoanal reflexes had latencies of 9.0 to 13.0 ms (males) and 6.5 to 9.0 ms (females). Anal reflex latencies were significantly (P < 0.05) longer for contralateral, opposed to ipsilateral, stimulation and were significantly (P < 0.05) longer in males than in females. Genitoanal reflex latencies were also significantly (P < 0.05) longer in males than in females, reflecting the more peripheral stimulation site in males.

Anal reflex responses could be recorded in 2 feline clinic patients with such severe perineal trauma that pudendal nerve function could not be manually evaluated. A potentially favorable prognosis was given in each instance on the basis of detection of the response. One cat eventually recovered. The other was euthanatized because of other problems, and the sacral part of the spinal cord, sacral nerve roots, and pudendal nerves were found to be intact at necropsy.
Lysozyme concentrations in the tears of cattle, goats, and sheep
Authors: Brightman Alan H. , Wachsstock Rand S. , Erskine Ron
Published: January 2024

Tear samples were collected from 1 eye of each of 40 cows, 27 sheep, 5 goats, and 5 human beings. Additionally, 10 bovine tear samples were pooled and concentrated. Spectrophotometric assays, using Micrococcus lysodeikticus, were performed on each sample to detect lysozyme activity expressed in hen egg lysozyme (hel) equivalents. Lysozyme activity was not detected in tears of cows, but 158.8 ± 159.3 mg of hel/ml was detected in tears of sheep, 220.7 ± 37.5 mg of hel/ml in tears of goats, and 216.3 ± 86.2 mg of hel/ml in tears of human beings.

In pooled bovine tear samples, lysozyme activity was not detected on plate assay and lysozyme protein was not detected on Polyacrylamide gel electrophoresis, column chromatography, or immunoelectrophoresis with rabbit anti-bovine tear antibodies. On the basis of these observations, we concluded that the basic ocular protective mechanism in bovine tears is not lysozyme. Other antibacterial proteins such as lactoferrin, transferrin, complement, or β-lysin may, therefore, be of primary importance in protecting the bovine eye.
Gram-negative bacterial infections of the mammary gland in cows
Authors: Todhunter Deborah A. , Smith K. Larry , Hogan Joseph S. , Schoenberger Pamela S.
Published: January 2024

Naturally acquired gram-negative bacterial intramammary infections (n= 160) were studied in 99 cows over a 2-year period. Escherichia coli, Klebsiella spp, Serratia spp, Enterobacter spp, and unidentified gram-negative bacteria were isolated from 28.8, 39.4, 9.4, 5.0, and 11.2%, respectively, of infected mammary glands. A majority (61%) of intramammary infections were first detected during the nonlactating period. Gram-negative bacteria isolated during the first half of the nonlactating period were predominantly Klebsiella spp, Serratia spp, and Enterobacter spp. Onset of E coli intramammary infections was more prevalent during the second half of the nonlactating period and during the first 7 days of lactation. The majority (59%) of infections were < 28 days in duration, but Klebsiella spp and Serratia spp infections were of significantly (P < 0.05) greater duration than infections with E coli. The greatest percentage (47%) of gram-negative bacterial intramammary infections were first detected during the summer.
Lesions and localization of viral antigen in tissues of cattle with experimentally induced or naturally acquired muscosal disease, or with naturally acquired chronic bovine viral diarrhea
Authors: Wilhelmsen Catherine L. , Bolin Steven R. , Ridpath Julia F. , Cheville Norman F. , Kluge John P.
Published: January 2024

Tissues from cattle that died of experimentally induced mucosal disease (n = 3), naturally acquired mucosal disease (n = 6), or naturally acquired chronic bovine viral diarrhea (n = 4) were examined. Consistent findings were lymphocytic depletion of lymphoid tissues, degeneration of myenteric ganglion cells, and mild adrenalitis. Intracytoplasmic viral antigen was detected in myenteric ganglia and in endocrine glandular cells. Noncytopathic virus was isolated from all cattle, and cytopathic virus was isolated from 12 of 13 cattle.
Biochemical study of repair of induced osteochondral defects of the distal portion of the radial carpal bone in horses by use of periosteal autografts
Authors: Vachon Anne M. , McIlwraith C. Wayne , Keeley Fred W.
Published: January 2024

Periosteal autografts were used for repair of large osteochondral defects in 10 horses aged 2 to 3 years old. In each horse, osteochondral defects measuring 1.0 × 1.0 cm2 were induced bilaterally on the distal articular surface of each radial carpal bone. Control and experimental defects were drilled. Periosteum was harvested from the proximal portion of the tibia and was glued into the principal defects, using a fibrin adhesive. Control defects were glued, but were not grafted.

Sixteen weeks after the grafting procedure, the quality of the repair tissue of control and grafted defects was assessed biochemically. Total collagen content and the proportion of type-II collagen were determined. Galactosamine and glucosamine contents also were determined. From these measurements, contents of chondroitin and keratan sulfate and total glycosaminoglycan, and galactosamine-to-glucosamine ratio were calculated. All biochemical variables were compared with those of normal equine articular cartilage taken from the same site in another group of clinically normal horses. Total collagen content was determined on the basis of 4-hydroxyproline content, using a colorimetric method. The proportions of collagen types I and II in the repair tissue were assessed by electrophoresis of their cyanogen bromide-cleaved peptides on sodium dodecyl sulfate slab gels. Peptide ratios were computed and compared with those of standard mixtures of type-I and type-II collagens. Galactosamine and glucosamine contents were determined by use of ion chromatography.

In general, the biochemical composition of repair tissue of grafted and nongrafted defects was similar, but clearly differed from that of normal articular cartilage. Total glycosaminoglycan content, galactosamine and glucosamine contents, and galactosamine-to-glucosamine ratio of grafted and nongrafted defects were all significantly (P < 0.05) less than corresponding values in normal equine articular cartilage. By contrast, total collagen content of neocartilaginous tissues of grafted and nongrafted defects was greater than that of normal articular cartilage, although the difference was not significant. The proportion of type-I and type-II collagens in repair tissue in grafted and nongrafted defects was 70 and 30%, respectively. The fibrous nature of the repair tissue reported in a companion morphologic and histochemical study was substantiated by the biochemical results. We concluded that use of periosteal autografts did not improve the healing of osteochondral defects.
Changes in serum immunoglobulin values in kittens after ingestion of colostrum
Authors: Yamada Takatsugu , Nagai Yoshinori , Matsuda Motoo
Published: January 2024

Immunoglobulin values were determined in fetal and kitten sera. In the fetal and precolostral kitten sera, only IgG was detected, except in 1 case in which IgM was detected. The IgG, IgA, and IgM were transferred to the kittens through colostrum ingestion with some selectivity. Concentration of the transferred IgG, IgA, and IgM decreased significantly with half-lives of 4.15 ± 1.29 days, 2.03 ± 0.33 days, and 2.2 ± 1.2 days, respectively. As a result of this decrease and increase of de novo immunoglobulin synthesis, IgG, IgA, and IgM were at their lowest values when kittens were 20 to 25 days, 14 to 20 days, and 8 to 10 days old, respectively. After their nadir was reached, IgG values increased gradually, IgA slowly, and IgM rapidly, as a result of de novo immunoglobulin synthesis. When the kittens were 90 days old, their immunoglobulin values were 80% (IgG), 7% (IgA), and 100% (IgM), compared with those of adult cats. These findings suggest that kittens that receive inadequate colostrum from their mothers will be particularly susceptible to infection after they are 5 weeks old.
Use of pulsed-wave Doppler echocardiography to determine aortic and pulmonary velocity and flow variables in clinically normal dogs
Authors: Brown Donald J. , Knight David H. , King Robert R.
Published: January 2024

Transcutaneous pulsed-wave Doppler echocardiography was used to obtain velocity signals from the aortic and pulmonary roots of clinically normal adult dogs tranquilized with acepromazine. Doppler-derived variables included peak ejection velocity, ejection time, and velocity-time integral. The cross-sectional areas of the left and right ventricular outflow tracts were estimated from diameters of the respective orifices measured from two-dimensional echocardiographic images. These data were used to calculate stroke volume and cardiac output for each ventricle. Linear, single variable regressions of ejection time, velocity-time integral, and peak velocity with body weight showed no significant correlations. Significant correlations existed between body weight and estimated left and right ventricular stroke volume and cardiac output. A close correspondence existed between pulmonary and aortic determinations of velocity-time integral, stroke volume, and cardiac output. These results provide an initial framework for interpretation of clinical data by veterinary cardiologists.
Field evaluation of a commercial M-protein vaccine against Streptococcus equi infection in foals
Authors: Hoffman Andrew M. , Staempfli Henri R. , Prescott John F. , Viel Laurent
Published: January 2024

A double-blind randomized clinical trial was undertaken to determine the value of parenterally administered Streptococcus equi M-protein vaccine in foals during an epizootic of strangles. Weaned mixed-breed foals (n = 664) housed on 2 adjacent feed-lots (A and B) arrived over a 5-day period, 2 weeks before primary vaccination. Foals in lot B (n = 114) were randomly administered vaccine (n = 59) or saline solution (placebo; n = 55) on 3 occasions at biweekly intervals. Foals in lot A (n = 450) were given 1 dose of vaccine (n = 225) or placebo. The following clinical observations were scored blindly by a single observer for all foals in lot B and for 120 (randomly sampled) foals in lot A on a single day, 2 (lot B) and 6 (lot A) weeks after final vaccination: cervical lymphadenopathy, type of bilateral nasal discharge, and palpable swelling at injection site(s). Bacteriologic culture of nasal swab specimens or lymph node aspirates from selected foals with clinical disease yielded Sequi. Cervical lymphadenopathy was observed in 17 of 59 (29%) vaccinates and 39 of 55 (71%) nonvaccinated controls in lot B and in 32 of 60 (53%) vaccinates and 29 of 60 (48%) controls in lot A. Contingency χ2analysis confirmed significantly lower cervical lymphadenopathy rate (χ2= 18.5; P < 0.001) and prevalence of mucopurulent nasal discharge (χ2= 11.4; P < 0.01) for vaccinates in lot B only. Swelling(s) at the vaccine injection site were palpated in 44% of lot B and 29% of lot A vaccinates vs < 2% of placebo controls. In the face of intense natural exposure, foals inoculated 3 times with M-protein vaccine were less than half as likely to have clinical signs of strangles as were nonvaccinated horses.
Osteochondrosis and juvenile spavin in equids
Authors: Watrous Barbara J. , Hultgren Bruce D. , Wagner Pamela C.
Published: January 2024

Thirty-six of 50 young equids examined at necropsy for gross pathologic and histopathologic evidence of osteochondrosis were determined to have lesions characteristic of this disorder in the distal joints of the tarsus. Abnormalities ranged from retained endochondral cores underlying undisturbed articular cartilage surfaces to clefts, subchondral osseous cyst-like lesions, and cartilage ulceration. Our findings supported the conclusion that osteochondrosis may cause spavin in the juvenile equid.
Recombination of pseudorabies virus vaccine strains in swine
Authors: Henderson Louise M. , Levings Randall L. , Davis Arthur J. , Sturtz Dawn R.
Published: January 2024

We report here genetic recombination between 2 USDA-licensed vaccine strains of pseudorabies virus co-inoculated into swine. The vaccine strains, one of which was a conventionally attenuated strain and the other, a genetically engineered deleted strain containing a negative immunologic marker, had complementary genomes. Co-inoculation resulted in the creation of novel strains of pseudorabies virus containing negative immunologic markers with restored virulence genes. Plaque-purified recombinant progeny viruses were found in 2 litters of pigs in which both strains were co-inoculated im, a litter in which both strains were co-inoculated oronasally, and a litter in which the conventionally attenuated strain was inoculated oronasally and the genetically engineered strain was inoculated im. Recombinant phenotypes and recombinant restriction fragment patterns were observed. The creation, spread, and potential misdiagnosis of these types of recombinant strains could disrupt control and eradication programs that are based on the serologic identification of swine infected with potentially virulent strains of pseudorabies virus.
Frequency and severity of osteochondrosis in horses with cervical stenotic myelopathy
Authors: Stewart Randolph H. , Reed Stephen M. , Weisbrode Steven E.
Published: January 2024

We compared the frequency and severity of osteochondrosis lesions in young Thoroughbred horses with cervical stenotic myelopathy (csm) vs that in clinically normal Thoroughbreds of the same age. All lesions of the cervical vertebrae and appendicular skeleton were classified histologically as osteochondrosis or nonosteochondrosis and were measured for severity. Minimal sagittal diameter was significantly smaller in horses with csm from C2 through C6; no difference was detected at C7. Severity of cervical vertebral osteochondrosis was greater in the horses with csm, however frequency was not different. Frequency and severity of nonosteochondrosis lesions were not different in cervical vertebrae or appendicular skeleton. Frequency and severity of appendicular skeleton osteochondrosis lesions were both greater in horses with csm. Osteochondrosis and nonosteochondrosis lesions were more severe on facets at sites of compression than on facets at noncompressed sites in horses with csm. However, compression was also observed at sites with no articular facet lesions. The association of widespread osteochondrosis and spinal canal narrowing with csm suggests csm may represent a systemic failure in the development or maturation of cartilage and bone.
Effect of milk stasis on Brucella abortus infection of the mammary gland in goats
Authors: Meador Vincent P. , Deyoe Billy L.
Published: January 2024

To compare the effects of milk stasis and milk flow on Brucella abortus infection of the mammary gland under the same systemic conditions, primiparous goats (n = 5) were inoculated iv with B abortus on the day of parturition, and suckling by their neonates was restricted to one mammary gland. Goats were euthanatized and necropsied at 3 weeks after inoculation, and milk, mammary glands, and supramammary lymph nodes were evaluated by bacteriologic, histologic, and immunoenzymatic staining techniques. Nonnursed mammary glands had high titers of brucellae in milk, moderate interstitial mastitis, and brucellar antigen in macrophages located primarily in alveolar and ductal lumina. Brucellae often filled the macrophage cytoplasm. In contrast, nursed mammary glands had fewer brucellae in milk, minimal inflammatory changes, and no detectable brucellar antigen in histologic sections. Hyperplastic changes were only seen in supramammary lymph nodes draining nonnursed mammary glands; these contained more brucellae than lymph nodes draining nursed mammary glands. These studies show that milk stasis may be the sole cause of increased susceptibility of nonnursed mammary glands to B abortus infection.