bluuebunny/crossref_metadata_2025 huggingface dataset:
Direct current stimulation of bone production in the horse: Preliminary study with a “gap healing” model
Authors: Collier M. A. , Brighton C. T. , Norrdin R. , Twardock A. R. , Rendano V. T.
Published: February 2025

The effect of a 20-μA direct-current implantable bone growth stimulator (bgs) on bone production with a “gap healing” model in the horse was evaluated. The right and left 4th metatarsal bones (Mt-4) were used in 7 adult horses to create the “gap healing” model. A 4-mm section of the Mt-4 bone was resected bilaterally in each horse. The bgs was surgically placed into the 7 left Mt-4 defects. The 7 right Mt-4 defects served as controls. Six horses survived the 16-week experimental period.

Signs of pain, decreased range of limb motion, or lameness was not observed in any animal during the 16 weeks. None of the animals showed complete healing radiographically. Four stimulated sites showed less periosteal reaction and 2 showed greater reaction than the 6 controls. The greatest amount of periosteal reaction or bone resorption was seen around the screws and plates in both groups. Uptakes of 99mTc-MDP in counts/pixel for control sites and stimulated sites were 7.90 and 8.25 in the “gap defect” and 5.19 and 5.06 in the areas adjacent to the gap defect. The ratio of uptake between the gap defect and adjacent area was 1.5 and 1.58 respectively. Biocompatability of the bgs was excellent; however, 1 horse had a broken cathode wire 5 cm from the generator capsule at 6 weeks. All polyethylene cathode sheaths were fluid filled at 16 weeks. The average mineralization rates were 1.57 ± 0.34, 1.71 ± 0.28 mm/day and bone formation activity was 0.0182 ± 0.171, and 0.0168 ± 0.0149 mm2/day for control limbs and stimulated limbs, respectively.

There was no significant difference between groups in any of the histomorphometric values measured. Direct current (20 μA) did not increase bone production in this experiment. Methods to objectively evaluate electrically induced osteogenesis and a “gap defect” model for bgs research on the horse are discussed. The results provide a basis for additional research on electrical stimulation of fractures in the horse and for dose-response studies.
Control of Isospora suis-induced coccidiosis on a swine farm
Authors: Ernst John V. , Lindsay David S. , Current William L.
Published: February 2025

Results of a program designed to control neonatal porcine coccidiosis on a total confinement, farrow-to-finish swine farm are reported. The control program consisted of washing, phenol disinfection, and steam cleaning of farrowing houses and treatment of sows with amprolium HCl before and after farrowing. Before initiation of the control program, 88.9% of the sows examined in the farrowing house were negative for coccidian oocysts, 9.9% were positive for Eimeria spp, and 1.2% were positive for Isospora suis. Most pigs nursing on sows before initiation of the control program had diarrhea at 5 to 10 days of age, which led to dehydration and weight loss. Morbidity was high, and mortality was moderate. Composite fecal samples from these litters were all positive (100%) for I suis. After initiation of the control program, 99.6% of the sows examined in the farrowing house were negative for coccidian oocysts and 0.4% were positive for Eimeria spp. Clinical signs of coccidiosis were rarely present in nursing pigs examined after the control program was initiated; however, I suis was still present in 19.8% of the composite fecal samples from pigs examined. An association between oocyst production in sows and I suis infections in pigs was not found in the present study. Oocysts of Eimeria spp were not found in the feces from the pigs.
Effects of three diets on dogs with induced chronic renal failure
Authors: Finco Delmar R. , Crowell Wayne A. , Barsanti Jeanne A.
Published: February 2025

Healthy mixed-bred dogs of both sexes had renal mass surgically reduced and were allowed 2 to 3 months for hypertrophy of the remnant kidney. They were then allotted into 3 groups with equal renal function and were fed 1 of 3 diets that differed in composition. Group 1 dogs (n = 6) were fed moist food that contained 50% protein, 2.34% Ca, and 1.64% P with a P-binding agent (basic aluminum carbonate gel) added. Group 2 dogs (n = 6) were fed a dry diet that contained 24.5% protein, 1.26% Ca, 1.21% P, and the same P-binding agent as used for group 1. Group 3 dogs (n = 7) were fed a moist diet that contained 16.1% protein, 0.38% Ca, and 0.3% P without a P-binding agent. Each group was fed its diet for 92 days and monitored for responses. Mortality associated with uremia occurred in 2 of 6 group 1 dogs, 0 of 6 group 2 dogs, and in 2 of 7 group 3 dogs. Among survivors, clinical signs were seen in the more azotemic dogs of group 1, but not in dogs of groups 2 and 3. The blood urea nitrogen, plasma P concentrations, and pcv values were most favorable in group 3 and least favorable in group 1. Marked differences between groups were not seen in plasma concentrations of protein, albumin, or Ca or in plasma alkaline phosphatase activity.

Values for glomerular filtration rate did not change in any group during the experiment. Significant differences between groups were not seen in brain mineral concentration, kidney mineral concentration, or kidney histologic findings. Thus, progression of renal disease did not occur with any of the diets under the conditions of the study.
Serum pancreatic polypeptide and amylase concentrations in dogs with experimentally induced acute pancreatitis
Authors: Murtaugh R. J. , Jacobs R. M. , Sherding R. G. , O'Dorisio T. M.
Published: February 2025

Serum concentrations of immunoreactive pancreatic polypeptide (ipp) were measured serially for 7 days after experimental induction of acute hemorrhagic pancreatitis in dogs by infusion of oleic acid into the pancreatic duct. The mean serum ipp concentrations in dogs with pancreatitis were increased significantly (P = 0.013) for 96 hours after induction of pancreatitis. Providing food at 108 hours resulted in significant increases (P = 0.032) in mean serum ipp concentrations in sham-operated control dogs compared with dogs with induced pancreatitis. This was attributed to cephalic-phase release of ipp due to a conditioned response that resulted from feeding immediately after each blood sampling. Mean serum ipp concentrations returned to base line more quickly than did mean serum amylase concentrations in dogs with pancreatitis.
Oral papillomatosis in New Zealand white rabbits
Authors: Sundberg John P. , Junge Randall E. , El Shazly Mohamad O.
Published: February 2025

Oral papillomas were seen in 31% of New Zealand white rabbits (n = 51) examined from 2 local sources. Papillomavirus structural antigens were detected by the peroxidase-antiperoxidase technique in cells of the stratum spinosum which contained basophilic intranuclear inclusions. Homogenates of papillomas hemagglutinated mouse rbc and also induced papillomas on the ventral surface of tongues, but not bulbar conjunctiva or vulva, of susceptible rabbits. The same oral papilloma homogenate induced fibromas in neonatal hamsters. Homogenates of hamster fibromas did not cause lesions on tongues of susceptible rabbits.
Evaluation of jackrabbits as nonruminant hosts for Anaplasma marginale
Authors: Zaugg J. L. , Newman B. A.
Published: February 2025

Two black-tailed jackrabbits (Lepus californicus), 1 splenectomized and 1 intact, were inoculated with 0.2 ml of a 1:5 dilution of a Florida Anaplasma marginale stabilate. Five months later, both hares were inoculated with 1 ml of whole blood from a calf with acute anaplasmosis. Neither hare developed any signs of clinical anaplasmosis. Pooled blood (7 ml) from these jackrabbits which was inoculated into 2 Anaplasma-susceptible, splenectomized calves failed to induce hematologic or serologic signs of anaplasmosis for at least 90 days.

Two susceptible, splenectomized calves were inoculated with 35 ml of pooled whole blood from 9 wild-collected black-tailed jackrabbits from a known anaplasmosis enzootic area. Both steers remained free of anaplasmosis signs for 90 days.
Pathogenesis and electron microscopic changes of spherulogenesis of Coccidioides immitis (valley fever)
Authors: Gabal M. A.
Published: February 2025

Pathogenesis and electron microscopic changes of spherulogenesis of Coccidioides immitis were determined. The organism showed a strong affinity for lung tissue, with granuloma developing in 100% (n = 40) of animals after subcutaneous and intraperitoneal inoculation. Intranasal instillation of the arthrospores resulted in moderate granuloma, with a markedly low frequency rate of infection in 11 animals (55%). Intradermal inoculation and skin scarification did not induce systemic infection. Unlike other routes used to induce infection, only 30% of the mice showed cutaneous changes, whereas in the group infected by skin scarification, 25% of the animals revealed pathologic changes. Indurated tiny nodular lesions developed in the skin at the site of the inoculation. The lesions did not ulcerate, and complete resolution was observed in 4 to 6 weeks.

Electron microscopy of the spherulogenesis showed that the tissue form of the fungus replicated in the host tissues by segmentation of the innermost stratum of the wall of the spherule. The layer appeared to function as a germinating center, and as many as 8 spores of irregular size and shape were produced within a kidney-shaped segment. Many segments were in each spherule. The spores were separated, pushed more centrally, and became rounded to become the endospores. When the endospores were freed, each developed into a spherule.
Effect of protective padding on forelimb intracompartmental muscle pressures in anesthetized horses
Authors: Lindsay W. A. , Pascoe P. J. , McDonell W. N. , Burgess M. L. F.
Published: February 2025

Wick catheters were used to measure intracompartmental muscle pressures (icmp) within the long heads of the triceps brachii and extensor carpi radialis muscles of 8 horses maintained under halothane anesthesia while their breathing was controlled by intermittent positive-pressure ventilation. Blood gas, cardiac output, and blood pressure determinations were monitored to maintain a stable plane of anesthesia. The horses were positioned in left lateral recumbency and were placed sequentially on each of 4 contact surfaces for 1 hour. The 4 surfaces used for each horse were concrete, foam rubber, air dunnage bag, and a water mattress. Hematologic and biochemical determinations were made before and 24 hours after anesthesia. All horses recovered from the anesthesia. One horse had forelimb lameness for 36 hours after anesthesia, which was clinically diagnosed as a myoneuropathy. The icmp values were markedly elevated in the muscle bellies of the lower limb of all horses. Supporting the horse on a water mattress caused the least dramatic pressure elevation and foam caused the most.

The triceps muscle and, to a lesser extent, the extensor carpi radialis muscle of the lower limb are at risk of ischemia in anesthetized horses because the icmp may exceed the critical closing pressure of 30 mm of Hg required for capillary blood flow.
Chondrolysis associated with cartilage canals of the epiphyseal cartilage of the distal humerus of growing pigs
Authors: Kincaid S. A. , Allhands R. V. , Pijanowski G. J.
Published: February 2025

The articular-epiphyseal (a-e) cartilage of the distal humeri of 7 pigs weighing 13.1 to 18.2 kg and of 3 pigs weighing 36.4 to 40.9 kg was studied. Frozen samples of a-e cartilage were stained for the presence of reduced nicotinamide adenine dinucleotide dehydrogenase, lactate dehydrogenase, isocitrate dehydrogenase, and uridine diphosphate galactose-4-epimerase. Additional frozen sections and paraffin-processed sections were stained using the Alcian blue-critical electrolyte concentration method, safranin 0-fast green, and hematoxylin and eosin. An area of grossly visible, opaque a-e cartilage of the medial condyle corresponded to regions of chondrolysis of the epiphyseal cartilage. The chondrolytic regions contained chondrocytes that did not stain for enzymes, had reduced staining for proteoglycans in the matrix, and were located at the site where the a-e cartilage increased in thickness. Cartilage canals were associated with the chondrolytic areas. Cartilage canals in both groups of pigs were commonly in various stages of chondrification, some of which were associated with degenerative cartilage. The regions of chondrolysis may indicate sites of biomechanical weakness in the a-e cartilage during the transformation of the epiphyseal cartilage into bone.
Effects of intravesical hydrostatic pressure and volume on the distensibility of the canine prostatic portion of the urethra
Authors: Johnston Gary R. , Feeney Daniel A. , Osborne Carl A. , Johnston Shirley D. , Smith Frances O. , Jessen Carl R.
Published: February 2025

Positive-contrast retrograde urethrocystograms were obtained serially on 12 male dogs weighing 11.4 to 23.2 kg before, during, and after the injection of contrast medium until the urinary bladder neck and prostatic and membranous portions of the urethra remained open and distended as viewed by fluoroscopy. Correlations of intravesical volumes and pressures required to achieve maximum distension of the midprostatic portion of the urethra with body weight and surface area were not significant.

Because of the variability in intravesical volumes and pressures encountered at maximum distension of the prostatic portion of the urethra, a dose of contrast material expressed relative to body weight or surface area could not be determined for consistently providing maximum distension of the prostatic portion of the urethra.
Anatomic and radiographic appearance of a sesamoid bone in the tendon of origin of the supinator muscle of dogs
Authors: Wood A. K. W. , McCarthy P. H. , Howlett C. R.
Published: February 2025

Radiologic and anatomic studies of the elbow of 100 dogs of 17 different breeds showed that a sesamoid bone may be located in a constantly present sesamoid cartilage associated with the tendon of origin of the supinator muscle. The sesamoid was observed in 31% of the radiographs of 100 supinator tendons dissected from 50 of the dogs. The bone was usually bilateral and was best demonstrated in craniocaudal medial-to-lateral oblique radiographs of the elbow where it articulated with the craniolateral aspect of the head of the radius.
Healing of surgically created defects in the equine superficial digital flexor tendon: Effects of pulsing electromagnetic field therapy on collagen-type transformation and tissue morphologic reorganization
Authors: Watkins J. P. , Auer J. A. , Morgan S. J. , Gay S.
Published: February 2025

The effect of pulsing electromagnetic field (pemf) therapy on the healing of surgically created defects in equine superficial digital flexor tendons was evaluated. Defects were created in both front superficial digital flexor tendons of 20 horses. The defect in 1 limb was exposed to a pemf for 2 hours daily. The other limb served as a control. Histologic and immunofluorescent evaluations were done in horses killed at postsurgical weeks 2, 4, 8, 12, and 24. Therapy with the pemf significantly (P < 0.05) delayed the maturation of the tissue formed within the defect at postsurgical weeks 8 and 12, as determined by histologic examination. The collagen-type transformation was also delayed by the pemf therapy, but to a degree that was not significant.
Canine Rocky Mountain spotted fever: A kennel epizootic
Authors: Breitschwerdt Edward B. , Meuten Donald J. , Walker David H. , Levy Michael , Kennedy Karen , King Memorie , Curtis Barbara
Published: February 2025

Within a period of 5 consecutive days after the initial observation of illness was made, 7 of 12 Siberian Husky dogs developed clinical signs of Rickettsia rickettsii infection. One dog died and was necropsied. Clinical signs of infection consisted of lethargy, anorexia, ocular and nasal discharges, and neurologic disorder (incoordination and rolling). Scleral blood vessel injection, fever, lymphadenomegaly, splenomegaly, and increased bronchovesicular lung sounds were prominent findings. Clinical laboratory test results identified decreased platelet numbers, variable neutrophil counts, increased serum alkaline phosphatase activity, hyponatremia, hypokalemia, and bilirubinuria.

Diagnosis of Rocky Mountain spotted fever was confirmed by serologic evaluation of acute and convalescent sera, using the microimmunofluorescence technique, and R rickettsii antigen was determined by demonstration of intracellular rickettsial organisms in vascular endothelial cells of brain and lung (stained with carbol-basic fuchsin and aqueous malachite green) and by demonstration of spotted fever-group rickettsiae in tissues by direct fluorescent antibody technique. Near-simultaneous naturally occurring tick-borne infection of 7 dogs with R rickettsii documents an unreported occurrence.
Appearance of ovine progressive pneumonia virus outside the United States
Authors: Perk K. , Irving S. G. , Yaniv A. , Gazit A.
Published: February 2025

A recently isolated Israeli retrovirus from a sheep with maedi-visna was compared with other retroviruses, using cDNA-RNA hybridization in solution. The Israeli isolate was shown to have close, if not identical, genetic homologic features with the ovine progressive pneumonia virus reported in the United States, rather than with those of the maedivisna viruses of European origin.
Chromosomal evaluation of a ewe lamb with atresia ani vaginalis
Authors: Swartz Helen A. , Vogt Dale W. , Michalski Karen A. , Warren John E. , Kiesling David
Published: February 2025

Chromosomes of a ewe lamb born with atresia ani vaginalis were examined after a 72-hour culture of peripheral whole blood. The 2n number of chromosomes was 54,XX, with no apparent deviation from normality. Pedigree analysis of the ewe lamb indicated that her sire and dam were only slightly related (Rsd = 0.59%); therefore, the amount of inbreeding of the lamb was small (Fx = 0.30%).
Epizootiologic investigations of a diarrheic syndrome in fattening pigs
Authors: Jestin A. , Popoff M. R. , Maké S.
Published: February 2025

A diarrheic syndrome linked to Clostridium perfringens was observed in fattening pigs. A good correlation was observed between the onset and the severity of diarrhea and the fecal passage of C perfringens enterotoxin. Intestinal fluids from affected pigs had activity comparable with that detected in a purified C perfringens enterotoxin. Seven pigs excreting enterotoxin were shown to develop serum antibodies to C perfringens enterotoxin.
Enzyme-linked immunosorbent assay for diagnosis of Corynebacterium (Rhodococcus) equi infection in foals
Authors: Takai Shinji , Kawazu Shinichiro , Tsubaki Shiro
Published: February 2025

An enzyme-linked immunosorbent assay (elisa) was used to diagnose Corynebacterium (Rhodococcus) equi infection in foals. In tests done with different antigen-extraction procedures (sodium dodecyl sulfate, sodium deoxycholate, polyoxy-ethylene [9] p-tert-octylphenol, polyoxy-ethylene [9-10] p-tert-octylphenol, sonification, homogenization, and heat treatment at 121 C), Tween 20 was a satisfactory reactive antigen. Using hyperimmune rabbit sera or infected foal sera, we investigated the specificity and the sensitivity of the elisa with the Tween 20 antigen of the different serotypes or of the isolates. Corynebacterium equi strain ATCC 6939 antigen had the best activity for detecting antibodies to C equi in foals. Sera from 218 healthy horses, 11 healthy foals, 17 healthy newborn foals, a foal with suspected C equi infection, and 5 infected foals were evaluated for antibodies to C equi, using elisa. The optical density values of 206 healthy horses, 17 healthy newborn foals, and 9 healthy foals were < 0.1. Infected foal sera, except from foal 3, and serum from a foal with suspected C equi infection had higher optical density values. Using elisa, specific antibodies against C equi were detected in a naturally infected 6-week-old foal after the foal had a rapid increase in the number of bacteria in the feces and after the initial development of clinical signs of illness at 5 weeks of age. Therefore, elisa was useful for the early diagnosis of C equi infection in foals.
Light and electron microscopic comparisons of cutaneous fibromas in white-tailed and mule deer
Authors: Sundberg John P. , Hill David L. , Williams Elizabeth S. , Nielsen Svend W.
Published: February 2025

Cutaneous fibromas of white-tailed deer (Odocoileus virginianus), when compared with normal skin of the same species, had a thinner basement membrane; thickened stratum spinosum with numerous melanocytes, desmosomes, polyribosomes, and tonofilaments; focal hyperplasia of the stratum granulosum containing numerous large, electron-dense keratohyalin granules with irregular borders and containing occasional cells with diffuse intranuclear virus particles; and a moderately thickened stratum corneum with (although rarely) small crystalline arrays of virus particles. Normal mule deer (Odocoileus hemionus) skin was structurally similar to that of the white-tailed deer. Mule deer fibromas were similar to those in white-tailed deer, except for diffuse thickening of the stratum granulosum (the cells of which contained large keratohyalin granules of various electron densities with occasional composite granules) and except for a markedly thickened stratum corneum that contained numerous intranuclear viral inclusions. In negatively stained homogenates of tumors from both deer species, viral particles resembled papillomaviruses.
Erythrocyte volume distribution in rainbow trout
Authors: Haley P. J. , Weiser M. G.
Published: February 2025

Reference mean corpuscular volume and volume heterogeneity values for erythrocytes of 23 rainbow trout were measured, using an electronic particle counter, and were analyzed, using a particle-size analyzer and microcomputer. The mean (± sd) erythrocyte count was 1.5 × 106 ± 0.16 × 106 cells/µl, the mean corpuscular volume was 346 ± 25 fl, and the mean coefficient of variation of erythrocyte volumes was 29 ± 2.3%. All erythrogram curves were skewed to the right, representing a mean of 15.6 ± 3.5% of the total cells counted.
Assessment of compensatory renal function and [125I]iothalamate clearance in sheep
Authors: Filippich Lucio J. , English Peter B. , Ainscow Janet
Published: February 2025

Compensatory renal function and sodium [125I]iothalamate clearance were studied in 4 adult Merino ewes. Renal clearances of inulin (Cin), iothalamate (Ciot), and p-ammohippurate (Cpah) were used to measure renal function before and 7 and 170 days after 50% and 75% reductions in renal mass. Renal mass reduction to 50% of normal was achieved by ligation of the right renal artery, and to 25% of normal by ligating the right renal artery and branches of the left renal artery. Renal function (Cin and Cpah) after 50% renal mass reduction was 78% of normal on postligation day (pld) 7 and 64% of normal on pld 170. This decrease in renal function between pld 7 and 170 was significant (P < 0.05). Renal function (Cin and Cpah) after 75% renal mass reduction was 55% of normal on pld 7 and 48% on pld 170; however, this decrease in renal function between pld 7 and 170 was not significant. Results indicated that, shortly after 50% renal mass reduction by renal arterial ligation, renal function in ewes was greater than that previously reported after unilateral nephrectomy and that a further decrease in renal function developed within 6 months after ligation. The mean Ciot in healthy ewes was 2.46 ml/min/kg of body weight. In healthy ewes and in ewes after renal mass reduction, regression of the simultaneous Ciot and Cin was Ciot = 0.276 + 1.05 Cin. The Ciot was higher than the corresponding Cin, and remained significantly (P < 0.01) and consistently higher. Therefore, iothalamate can be used to estimate glomerular filtration rate in sheep, although a correction factor is required.
Detection of viral antigens in bluetongue virus-infected ovine tissues, using the peroxidase-antiperoxidase technique
Authors: Cherrington J. M. , Ghalib H. W. , Sawyer M. M. , Osburn B. I.
Published: February 2025

An indirect immunoperoxidase procedure was developed to detect viral antigens in bluetongue virus (btv)-infected tissues. Embryonating chicken eggs were infected with btv serotypes 10, 11, 13, or 17, and the chorioallantoic membranes were subsequently fixed in formalin and embedded in paraffin. The peroxidase-antiperoxidase (pap) system was used to examine the infected membranes for the presence of viral antigens. Sheep antisera raised against btv serotypes 10, 11, 13, and 17 served as the primary antibodies in the pap procedure. Specific staining was observed when each of these antisera was applied to membranes expressing antigens of homologous and heterologous btv serotypes. The pap method was rapid, reliable, and specific in its detection of btv.
Activity of closantel against experimentally induced Fascioloides magna infection in sheep
Authors: Stromberg B. E. , Schlotthauer J. C. , Seibert B. P. , Conboy G. A. , Newcomb K. M.
Published: February 2025

The efficacy of closantel against experimentally induced Fascioloides magna infection in sheep was studied. In each of 3 experiments, closantel was administered 8 weeks after the sheep were given (oral inoculation) 100 metacercariae of F magna. In the 1st experiment, closantel was given orally to 5 groups of 6 sheep each at dosages of 0 (nontreated control), 5, 7.5, 10, and 15 mg/kg of body weight. In the 2nd and 3rd experiments, groups of 10 or 12 sheep were treated to confirm the efficacy of the previously determined optimal dosage of 15 mg/kg. An additional group of sheep (n = 10) was used in the 3rd experiment to evaluate the efficacy of closantel given im at a dosage of 7.5 mg/kg.

Closantel given orally at a dosage level of 15 mg/kg was highly effective (94.6% to 97.7%) in reducing F magna burdens. Also, pathologic scores associated with the F magna infection were reduced by 81.3% to 92.6% in sheep given this dosage of closantel. Efficacy of the im administered dosage of 7.5 mg of drug/kg was equivalent to that of the 15 mg/kg oral dosage. Other than mild, transient lameness of the limbs which were injected with the drug (group 10), side effects were not observed.
Anthelmintic efficacy of flubendazole paste against nematodes and cestodes in dogs and cats
Authors: Vanparijs O. , Hermans L. , Van der Flaes L.
Published: February 2025

Small dogs and cats, naturally infected with nematodes and cestodes, were used in a critical test under laboratory conditions to determine the palatability and efficacy of flubendazole as a paste formulation. Subsequently, a control test in dogs was conducted under field conditions.

A 4.4% paste formulation was given at a dosage of 22 mg/kg of body weight once a day for 2 or 3 consecutive days.

In a critical test in dogs, the efficacy against Toxocara canis was 97.4% after a 2-day administration and 100% after 3 days. Toxascaris leonina seemed to be the most susceptible worm species, since either 2 or 3 treatments were 100% active. The efficacy against Uncinaria stenocephala was 97.5% after 2 treatments; the same dose level for 3 days improved the efficacy to 100%. The efficacy was 100% for the removal of Trichuris vulpis after a daily dosage for 2 days and 96.7% after 3 days. One of 2 dogs infected with Taenia pisiformis was cleared of the infection after a 2-day treatment, and 3 of 4 dogs were cleared after a 3-day regimen. All cats were cleared of Toxocara cati after 2 or 3 days of treatment. One of 2 cats infected with Hydatigera taeniaeformis was cleared of the infection after a 2-day treatment; a 3-day treatment in 7 cats was 100% effective.

The results in the laboratory test in dogs were confirmed under field conditions by a control test, based on the reduction of eggs per gram of feces count after treatment.

The paste formulation was well accepted by all dogs and cats without any side effects.
Bacterial isolates from tracheobronchial aspirates of healthy horses
Authors: Sweeney Corinne Raphel , Beech Jill , Roby Kate A. W.
Published: February 2025

Of tracheobronchial aspirates from 50 clinically healthy Thoroughbred racehorses, 4 (8%) had aerobic bacteria with recognized pathogenicity, 12 (24%) contained transient bacterial isolates, and 37 (74%) had no bacterial growth.

Of tracheobronchial aspirates from 36 pastured, nonracing racehorses, 3 (8%) had bacteria with recognized pathogenicity, 23 (64%) contained transient bacteria, and 10 (28%) had no bacterial growth. Anaerobes were not isolated from 12 of 12 pastured horses. Transient bacteria were isolated more often in the pastured horses.
Preliminary studies on the measurement of conjunctival oxygen tension in the foal
Authors: Webb A. I. , Daniel R. T. , Miller H. S. , Kosch P. C.
Published: February 2025

The capability of a transconjunctival oxygen monitoring system to provide an accurate and reliable means of observing arterial oxygenation trends was evaluated in 12 horse and pony foals between 5 and 20 days of age. Ten of the foals were anesthetized with isoflurane in oxygen and nitrous oxide, and 2 foals were conscious. Inspired oxygen concentration was manipulated by differing proportions of oxygen and nitrous oxide in the fresh gas supplied to the breathing circuit. With arterial oxygen tension values ranging from < 20 to > 400 mm of Hg, all foals had significant positive correlations between arterial and conjunctival oxygen tensions (P < 0.001). Although the system seemed accurate and reliable, monitoring oxygenation in awake and mobile foals may require a ring conformer made to fit the foal's eye.
Viral-like particles associated with naturally occurring transmissible venereal tumor in two dogs: Preliminary report
Authors: Amber E. I. , Isitor G. N. , Adeyanju J. B.
Published: February 2025

Naturally occurring canine transmissible venereal tumors in 2 dogs were examined ultrastructurally, using a transmission electron microscope. Typical nondegenerating cells of various shapes with normal cytoplasmic organellae were seen.

Degenerating and necrotic cells characterized by loss of normal organellae with vacuolations of the cytoplasm were in all sections studied. Icosahedral electron-dense particles (22 nm diameter) were in the degenerating and necrotic cells.

The uniqueness of this finding is not known. The shape and size of the particles indicate that there may be viral involvement.
Terminal deoxynucleotidyl transferase activity in thymocytes of kittens
Authors: Richerson Joan T. , Coleman Mary Sue , Brunner Cindy J. , Mattingly Steele F.
Published: February 2025

Activity of terminal deoxynucleotidyl transferase (TdT) was measured in the thymus of 8- to 14-week-old kittens. Microscopic evidence of involution or other morphologic changes were not observed in formalin-fixed hematoxylin and eosin-stained thymic tissue sections. Thymic tissue from young kittens (8 weeks old) had low TdT activity, as determined by enzymatic catalysis or immunoassay procedures. Markedly higher TdT activity was measured in thymic tissue of older kittens (13 to 14 weeks old). Feline TdT catalyzed the polymerization of deoxynucleotides at a higher rate in Mn2+ than in Mg2+. Results of protein immunoblotting experiments indicated that the major form of feline thymic TdT is a single, high molecular weight polypeptide in 13- to 14-week-old kittens. Detection of TdT activity in the feline thymus indicated that TdT may have the same diagnostic and therapeutic value in feline oncology as in human oncology.
Susceptibility of laboratory rats, hamsters, and mice to wound infection with Staphylococcus aureus
Authors: Donnelly Thomas M. , Stark Dennis M.
Published: February 2025

Response of rodents to experimentally induced subcutaneous infection was examined to determine whether laboratory rats used in invasive procedures have a superior ability to withstand wound infection than do hamsters and mice. Rats, hamsters, and mice were injected subcutane-ously with 109, 107, and 105 colony-forming units of Staphylococcus aureus. Quantitative counts of viable S aureus from the injection site, bactériologie cultures of heart blood, and histologic examinations of the subcutaneous tissues were performed.

Multiple linear regression of the quantitative data and equality of regression lines among groups were determined. Results indicated that the ability to eliminate bacteria varied between species and depended on the dose injected within each species. Compared with hamsters and mice at all doses, rats eliminated bacteria faster and had the mildest and most rapidly organized inflammatory response after inoculation. Experimental bacteremia developed in 3.7% of all animals evaluated, with no species-specific pattern. The rat was more resistant to localized wound infection with S aureus than were hamsters and mice.
Effect of antibodies to type 1 fimbriae on clearance of fimbriated Escherichia coli from the bloodstream of turkeys
Authors: Arp L. H.
Published: February 2025

Young turkeys (n = 20) were inoculated iv with fimbriated, virulent Escherichia coli EC1 (O78:K80: H9:F1). Blood samples were collected for bacterial quantitation at postinoculation minutes (pim) 10, 20, 30, 40, 50, and 60. Immediately after the pim 30 sampling, the turkeys were allotted into 4 groups (5 turkeys/group) and were injected iv with 1 of the following antisera: group 1, antibodies to F1 fimbriae (af); group 2, antibodies to E coli O78 antigen (ao); group 3, antibodies to live, fimbriated (F1+) homologous E coli (alec); or group 4, normal turkey serum (nts) collected from a healthy turkey. Compared with nts, alec and ao caused a significant reduction in blood-borne E coli, whereas ae did not reduce bacterial numbers. In addition, 2 groups of 10 turkeys were inoculated iv with live, F1+ or non-fimbriated (F1−) E coli EC1. Numbers of viable bacteria were determined in blood samples and liver specimens collected 2 minutes after inoculation. Compared with F1− bacteria, significantly more F1+ bacteria were found in liver specimens and significantly fewer F1+ bacteria were found in blood samples. Results indicated that antibodies to F1 fimbriae do not enhance clearance of F1+ E coli from the bloodstream of turkeys probably because F1+ bacteria are selectively cleared by the liver, even without antibody.
Efficacy of an albendazole feed formulation against bovine gastrointestinal nematodes including arrested larvae of Ostertagia ostertagi
Authors: Courtney C. H. , Greiner E. C. , Whitten R. D.
Published: February 2025

The efficacy of an albendazole feed premix formulation was compared with that of an albendazole drench suspension for control of gastrointestinal nematodes in 31 beef cattle. The premix (11 cattle) and drench suspension (9 cattle) were found to have similar efficacies at a dosage of 7.5 mg/kg of body weight. When compared with controls (11 cattle), both formulations caused significant (P < 0.05) reductions in worm counts with an efficacy of 98% or greater against adult Haemonchus placei, Ostertagia ostertagi, Trichostrongylus axei, Cooperia punctata, and C pectinata. There was no significant effect against arrested 4th-stage larvae of Ο ostertagi. Adverse effects of albendazole treatment were not observed, and the premix formulation was readily consumed by cattle.
N-Acetyl-β-d-glucosaminidase and antitrypsin in subclinically infected quarter-milk samples: Effect of bacteria and hemolysins, lactation stage, and lactation number
Authors: Mattila T. , Syväjärvi J. , Jensen Ν. E. , Sandholm M.
Published: February 2025

Interrelationships between N-acetyl-β-d-glucosaminidase (indicating cellular damage) and antitrypsin (indicating increased permeability between the blood and milk compartments) were evaluated in 1,411 quarter-milk samples collected during routine herd surveys. N-Acetyl-β-d-glucosaminidase was a more sensitive indicator of mild mastitis than was antitrypsin, whereas, in more severe mastitis, antitrypsin had a more constant deflection. The sensitivity of both determinants was associated with the virulence of bacteria. Production of bacterial hemolytic toxins was associated with a significant increase in both determinants. Penicillinase production by staphylococci was associated with selective increases of antitrypsin.
Effects of Pasteurella haemolytica lipopolysaccharide on selected functions of bovine leukocytes
Authors: Confer A. W. , Simons K. R.
Published: February 2025

Lipopolysaccharide (lps) was obtained from Pasteurella haemolytica serotype 1, using phenol-water extraction, and was evaluated for its ability to modify the biological activity of bovine leukocytes. The lps was not toxic to polymorphonuclear leukocytes (pmn). The lps preparation had little effect on random migration of pmn or mononuclear leukocytes (mnl), but caused a 2.5- to 3-fold increase in migration of cells within a whole peripheral blood leukocyte preparation. Phagocytosis of [125I]-labeled Staphylococcus aureus by pmn decreased with low (2.5 μg/106 cells) and high (65 μg/106 cells) concentrations of lps and increased with moderate concentrations of lps (5 to 25 μg/106 cells). The lps enhanced nitroblue tetrazolium reduction by pmn. Moderate lps concentrations (25 to 50 μg/106 cells) were mitogenic for mnl, whereas high lps concentrations (300 μg/106) inhibited [3H]thymidine incorporation by mnl.
Blood magnesium values in healthy cattle and in cattle affected with anaplasmosis and eperythrozoonosis
Authors: Brown Jesse E. , Hidalgo Richard J. , Jones E. Wynn , Boyle Carolyn R.
Published: February 2025

Magnesium (Mg) concentrations in plasma, serum, and erythrocytes (rbc) of calves subjected to splenectomy (sp), splenectomy-induced eperythrozoonosis (ep), and experimentally induced anaplasmosis (an) were determined and compared with pre-sp, pre-ep, and pre-an values. Mean serum and plasma Mg concentrations varied in parallel through most periods of the trial. Both were highest after sp, but neither value was significantly different from the pre-sp concentrations. Mean serum and plasma Mg values varied inversely with mean rbc values after sp and ep. Mean rbc Mg values increased significantly from previous periods during ep and an and after an, with the values after an being significantly higher than those at all other periods.

Mean plasma, serum, and rbc Mg concentrations were correlated to both mean percentage of parasitemia (%P) and packed-cell volume (pcv). The rbc Mg values increased significantly after mean %P reached 20 and the pcv began to decrease. There was evidence for a distinct lag variation in increasing rbc Mg concentrations with respect to both mean %P and pcv during an. A strong correlation was observed between the rbc Mg values and the %P occurring 5 days previously and the pcv occurring 3 days previously.
Effect of laryngeal hemiplegia and laryngoplasty on airway flow mechanics in exercising horses
Authors: Derksen F. J. , Stick J. A. , Scott E. A. , Robinson Ν. E. , Slocombe R. F.
Published: February 2025

The effect of left laryngeal hemiplegia on airway flow mechanics in 5 exercising horses was examined, and the efficacy of surgical repair by prosthetic laryngoplasty was evaluated. Measurements of the upper airway flow mechanics were made with horses on a treadmill (incline 6.38°) while standing (period A); walking at 1.3 m/s (period B); trotting at 2.6 m/s (period C); trotting at 4.3 m/s (period D); and standing after exercise (period E). Experiments were done on healthy horses before any surgical manipulation (control), at 10 days after left recurrent laryngeal neurectomy, and at least 14 days after prosthetic larynogoplasty.

Increasing treadmill speed from period A to period D progressively increased heart rate, respiratory frequency, peak inspiratory flow, and peak expiratory flow, but inspiratory resistance and expiratory resistance remained unchanged. Neither left recurrent laryngeal neutrectomy nor prosthetic laryngoplasty affected heart rate, respiratory frequency, peak expiratory flow, or expiratory resistance when compared with those values at the control measurement periods. Left recurrent laryngeal neurectomy resulted in inspiratory flow limitation at peak inspiratory flow of approximately 25 L/s, and increased inspiratory resistance at periods D and E. Subsequent prosthetic laryngoplasty alleviated the flow limitation and reduced inspiratory resistance at measurement periods D and E.
Duration of pneumoperitoneum in the dog
Authors: Probst Curtis W. , Stickle Russ L. , Bartlett Paul C.
Published: February 2025

The duration of pneumoperitoneum was examined in 12 adult and 4 immature dogs. Four dogs were given intra-abdominal injections of 110 ml of air/kg (group 1 ), 4 were given 55 ml of air/kg (group 2), and 4 were given 27.5 ml of air/kg (group 3). Also, 4 immature dogs were given 110 ml of air/kg (group 4). The number of days from creation of pneumoperitoneum until the radiographic absence of pneumoperitoneum averaged 25 days for group 1, 14 days for group 2, 9 days for group 3, and 17 days for group 4.
Influence of age and breed of equid on plasma copper and zinc concentrations
Authors: Cymbaluk Nadia F. , Bristol Frank M. , Christensen David A.
Published: February 2025

Plasma ceruloplasmin activities and plasma Cu and Zn concentrations were determined in 215 clinically normal equids of various ages and breeds. Newborn foals, regardless of breed, were hypocupremic, compared with adolescent and mature horses. The mean plasma Cu concentration of newborn Standardbred-Thoroughbred (std-tb) foals was 2.9 μmol/L, which was about one-sixth of plasma Cu concentrations of mature horses. Newborn draft-cross foals had higher (4.6 μmοl/L) plasma Cu concentrations than did newborn std-tb foals, but plasma Cu content was only one-fifth of the dams' concentrations. Draft-cross horses, regardless of age, had plasma Cu concentrations 15% to 40% higher than did std-tb horses. Plasma Cu concentrations of Quarter Horse yearlings were similar to those in draft-cross yearlings. Plasma ceruloplasmin activities revealed a curvilinear relationship to plasma Cu concentrations.

Plasma Zn concentrations of newborn and 1-week-old std-tb foals were 30% to 80% higher than those for yearling and mature std-tb horses. There were no differences between draft-cross neonates and their dams in plasma Zn concentration. Plasma Zn concentrations of neonatal and mature draft-cross horses were 22% higher than those obtained for all other equids. Age and breed of equid should be a consideration in interpretations of plasma Cu and Zn concentrations in equids.
Alveolar phospholipids of 17-day-old pigs exposed to microorganisms of nonpulmonic origin
Authors: Engen R. L. , Whipp S. , Hummel S. K.
Published: February 2025

Alveolar lining material was obtained from gnotobiotic pigs; gnotobiotic pigs exposed to aerobes, anaerobes, or mixtures of both microorganisms; and conventional farm-raised pigs. Alveolar lining material concentrations of phosphatidylcholine, sphingomyelin, phosphatidylserine, phosphatidylinositol, phosphatidylethanolamine, phosphatidylglycerol, and lysolecithin were determined. Seventy-four pigs were allotted to the following groups: 1—gnotobiotes (n = 13), 2—gnotobiotes with aerobes (n = 6), 3—gnotobiotes with anaerobes (n = 31), 4— gnotobiotes with anaerobes and aerobes (n = 2), 5—gnotobiotes with facultative anaerobes (n = 9), and 6—conventionally farm-farrowed (n = 13). The conventionally raised pigs had lysolecithin, sphingomyelin, and phosphatidylinositol concentrations that were significantly different from those of all other groups of pigs. Phosphatidylethanolamine was significantly decreased in group 6 pigs when compared with that in all other groups. There were also statistically significant differences between the gnotobiotic (group 1) and the exposed gnotobiotic (groups 2, 3, 4, 5) pigs, although the differences were less pronounced. Since intestinal microbes produce alveolar lining material phospholipid differences, studies need to be concerned with phospholipid changes that occur after exposure to lung-specific microorganisms and with physiologic changes in lung function associated with the phospholipid changes.
Factor VIII complex in canine plasma after submaximal treadmill exercise
Authors: Turrentine Mark A. , Hahn Allen W. , Johnson Gary S.
Published: February 2025

Exercise-induced changes in the plasma concentrations of coagulation factor VIII and von Willebrand factor were evaluated, using 8 random-source adult dogs that exercised on a treadmill for 5 to 10 minutes (mean running time = 8.3 minutes). Maximum treadmill speeds attained by the dogs were 11 to 18 km/hr, and the mean of the maximum individual speeds was 14.3 km/hr. Maximum heart rates of individual dogs during exercise were 190 to 250 beats/min with a mean of 218 beats/min (a 2.4-fold increase over the mean preexercise rate). Exercise did not induce significant increases in plasma concentrations of factor VIII coagulant activity, coagglutinin cofactor activity, or factor VIII-related antigen. Results indicated that submaximal exercise does not induce increases in plasma concentrations of coagulation factor VIII or von Willebrand factor in the dog.
Spontaneous expression of an endogenous retrovirus by the equine sarcoid-derived MC-1 cell line
Authors: Cheevers W. P. , Fatemi-Nainie S. , Anderson L. W.
Published: February 2025

A retrovirus is spontaneously released into the culture medium of the equine sarcoid-derived MC-1 cell line. The MC-1 virus did not exhibit in vitro transforming activity or replication when tested on equine fibroblasts or a variety of other mammalian cell cultures. Complementary DNA, synthesized using detergent-activated MC-1 virus RNA-dependent DNA polymerase, detected homologous sequences in the DNA of an established equine dermal cell line and in the DNA of primary equine dermal fibroblasts. Iododeoxyuridine or azacytidine induced a replication-deficient endogenous retrovirus in the normal fibroblasts and amplified the production of MC-1 virus by the tumor cells. It was concluded that the endogenous virus, repressed in normal equine cells, is spontaneously expressed by the tumor cells.
Sequence relationships of United States prototype and wild-type bluetongue virus RNA genomes investigated by northern blot hybridization analysis
Authors: Squire K. R. E. , Chuang R. Y. , Chuang L. F. , Doi R. H. , Osburn Β. I.
Published: February 2025

The 10 double-stranded RNA (dsRNA) genome segments of various isolates of bluetongue virus (btv) were separated on a Polyacrylamide gel, denatured in NaOH, and blotted onto 2-aminophenylthioether paper. Blotted dsRNA segments were detected, using radioactive probes, a cloned copy of DNA 70% fragment of genome segment 7 of btv-17, whole genome btv-17 copy DNA, or whole genome btv-17 dsRNA. These probes detected sequence diversities in different isolates of btv and these diversities are discussed in relation to the serotype and the electrophoretic migration patterns of the isolates.
Reclassification of North American leptospiral isolates belonging to serogroups Mini and Sejroe by restriction endonuclease analysis
Authors: Thiermann Alex B. , Handsaker Annette L. , Foley John W. , White Frank H. , Kingscote Barbara F.
Published: February 2025

The genomes of North American strains of leptospires belonging to serogroups Mini and Sejroe were analyzed and compared with those of reference strains by cleavage with restriction endonucleases.

The isolates selected for this study, when typed by the serologic method, were identified as serovars szwajizak, hardjo, and balcanica. However, the results of restriction endonuclease analysis (rea) indicated that a different classification existed. The 2 isolates typed as serovar szwajizak seem to be georgia by rea.

Isolates belonging to serovars balcanica and hardjo had rea patterns that differed from both reference strains. Differences were not observed in the rea patterns between balcanica and hardjo isolates. All hardjo and balcanica isolates examined are suggested to be classified into a previously described hardjo, rea subtype hardjo-bovis. Using the enzyme Hha1, these isolates were subdivided into 3 subgroups. When examining the rea pattern of the 17 reference strains in serogroup Sejroe, 3 identical pairs were observed: wolffi and roumanica; sejroe and polonica; and istrica and nyanza. The rea again indicated that it will be a valuable method for the classification of leptospires.