bluuebunny/crossref_metadata_2025 huggingface dataset:
Use of Solid Medium for Isolation of Leptospires of the Hebdomadis Serogroup from Bovine Milk and Urine
Authors: Thiermann A. B.
Published: February 2025

Leptospira interrogans serovars hardjo and szwajizak were isolated from the milk of experimentally infected cows only when using bovine albumin polysorbate-80 solid medium. Semisolid media, with and without the addition of 5-fluorouracil, and hamster inoculations were also used in the isolation attempts.

These cultural isolation methods were also compared using cows' urine. Semisolid medium with 5-fluorouracil proved to be the most successful. However, the other methods were satisfactory, with solid medium having the lowest percentage of cultural isolations.
Routine Isolation and Cultivation of Bovine Rotaviruses in Cell Culture
Authors: Bachmann P. A. , Hess R. G.
Published: February 2025

Using the bovine embryonic kidney cell line, Aubek, bovine rotaviruses were routinely isolated from fecal samples of calves with diarrhea. Of 125 fecal samples positive for rotavirus by immune electron microscopy and the enzyme-linked immunosorbent assay, 61 isolates were recovered and cultivated continuously.
Effects of Aflatoxins in Young Ponies
Authors: Aller Walter W. , Edds George T. , Asquith R. L.
Published: February 2025

Sixteen clinically normal, healthy ponies were randomly assigned to 4 groups and given aflatoxin B1 in doses of 0.045, 0.030, 0.015, and 0 (control) mg/kg of body weight per day for 21 days (or total doses of 0.945, 0.630, 0.315, and 0 mg/kg). The animals were allowed to recover for 3 months and then were reassigned to 4 treatment groups such that each group during the 2nd trial included a pony from each of the groups of the 1st trial. The animals in the new groups were intubated and were given aflatoxin in doses of 0.4, 0.2, 0.1, and 0 (control) mg/kg/day for 5 days (or total doses of 2.0, 1.0, 0.5, and 0 mg/kg).

Venous blood samples were drawn every other day to monitor for toxicosis; examinations were made for rbc and wbc counts, hemoglobin concentration, pcv, serum urea nitrogen, prothrombin time, and serum concentrations of aspartate aminotransferase, iditol dehydrogenase, alkaline phosphatase, albumin, γ-glutamyl transferase, and arginase.

There were no significant differences between treatment groups and controls (given no aflatoxin) in the toxicologic values examined for during the 1st trial. During the 2nd experiment, 2 of the ponies in the large-dose treatment group (2.0 mg/kg) demonstrated increased serum enzyme activities. These animals had been in the large-dose (0.945 mg/kg) and mediandose (0.63 mg/kg) groups during the 1st trial. Arginase, iditol dehydrogenase, and γ-glutamyl transpeptidase activities became increased on the 4th day of treatment and continued to increase until the 6th day of the experiment (1 day after treatment was terminated). These enzymes approached control group values at 10 days after cessation of treatment. These increases were indicative of hepatocellular toxicity.

It was concluded that the possibility of equine aflatoxicosis exists although ponies given high quality rations appear to be less susceptible than some other species. Prior exposure to aflatoxins may predispose to clinical toxicity on subsequent exposure, despite lack of expression of clinical signs.
Influences of Sequences of Environmental Factors on the Response of Chickens to Fasting and to Staphylococcus aureus Infection
Authors: Gross W. B. , Siegel P. B.
Published: February 2025

Weight gain of chickens following fasting was influenced by interactions between habituation to persons (socialization), stress (drinking water withheld) early in the life of the bird, and sex. Fasting affected socialized birds less than unsocialized birds. Body weight changes following Staphylococcus aureus infection were influenced by interactions between sex, stress early in life, socialization, and fasting. These 4 factors may also influence the occurrence of disease outbreaks in poultry farms.
Extraction, Separation, and Partial Characterization of Brucella abortus Antigens
Authors: Stone S. S. , Patterson J. M. , Deyoe B. L.
Published: February 2025

Brucella abortus isolates strain 19 (a vaccinal strain) and 458 (a virulent field isolate) were analyzed for antigenic differences. Whole cell preparations were extracted with detergents, salt solutions, and phenol-acetic acid-water (paw). Antigens were separated by starch block electrophoresis and sucrose density gradient centrifugation, serotested, and chemically analyzed. Six distinct precipitin lines were observed for the paw extract against hyperimmune bovine antisera. With sucrose density centrifugation or starch block electrophoresis, antigens were separated into (i) complement-fixing (cf) antigens and (ii) antigens that did not fix complement but formed precipitin bands. Reciprocal cf tests with purified cf antigen could not differentiate between the antigens from either isolate of Brucella.
Feline Population Dynamics: A Study of the Manhattan, Kansas, Feline Population
Authors: Nassar R. , Mosier J. E.
Published: February 2025

Analysis of the age-specific birth and survival rates and the age distribution in the pet population of cats in Manhattan, Kansas, revealed that the rate of population change (λ) was about 1.18. This means that under present birth and death rates, the cat population can increase by about 18% per year. In reality, the increase may not be as high since pet ownership may not increase by as much.

The frequency of spayed females of reproductive age in the Manhattan population was about 59%. This may not be sufficient to curb population growth. With the present age-specific survival rates, about 88% of the females should be spayed if the population is to remain stable.

The ratio of people to cats in Manhattan was estimated to be 5.2:1. The average number of cats per household was 0.508. The percentage of households with cats was 28 with an average of 1.74 cats per household. In comparison, the average number of dogs per household was 0.43 and the percentage of households with dogs was 43 with an average of 1.36 dogs per household.

The methods used in this study are useful for collecting and analyzing data to be used by governmental bodies and veterinarians concerned with proposals to regulate pet population growth and reproduction.
Influence of Increased Temperature on Anaplasma marginale Theiler in the Gut of Dermacentor andersoni Stiles
Authors: Kocan Katherine M. , Barron Selwyn J. , Holbert Donald , Ewing S. A. , Hair Jakie A.
Published: February 2025

Three splenectomized dairy calves were inoculated with a Virginia isolate of Anaplasma marginale Theiler and served as an infective source for laboratory-reared Dermacentor andersoni Stiles nymphs. One month after molting, groups of adult ticks were incubated at 37 C for 0, 1.5, 2.5, and 7 days. Gut homogenates were made from ticks representing each incubation period. Twenty-four susceptible, splenectomized dairy calves were each inoculated iv with a gut homogenate extracted from 50 adult ticks and monitored for patent A marginale infection. The prepatent periods were determined and used as a measure of infectivity. Gut homogenates made from ticks that had been incubated for 2.5 days produced infections with the shortest prepatent periods, an average of 28.5 days among 3 trials.
Changes in Gut-Associated Lymphoid Tissues of the Small Intestine of Eight-Week-Old Pigs Infected with Transmissible Gastroenteritis Virus
Authors: Chu Redman M. , Glock Robert D. , Ross Richard F.
Published: February 2025

The responses of the interepithelial lymphocytes (iel) and aggregated lymph nodules (aln; Peyer's patches) of the small intestines of 8-week-old pigs to transmissible gastroenteritis virus (tgev) infection were characterized at 12, 18, and 24 hours after pigs were inoculated.

There was no significant difference in numbers of iel between control and tgev-infected pigs at 12 and 18 hours. However, in pigs examined at 24 hours, there was a significant decrease in the number of iel in the duodenum and cranial portion of the jejunum and an increase of iel numbers in the nuclear level of the intestinal epithelium. Number and distribution were unchanged in the middle portion of the jejunum and the ileum.

Microscopic changes in tgev-infected pigs included microulceration of the dome epithelium (de) over the aln, especially in the cranial portion of the intestine, and villous atrophy in the entire length of the small intestine. Generally, tgev was found by means of peroxidase-antiperoxidase staining in areas where microscopic lesions occurred.

Electron microscopy revealed that M cells and ordinary microvillus-covered epithelial cells in the de embraced one or more lymphocytes, and formed a specialized cell complex or de complex. Most of the lymphocytes in the de complex possessed many organelles indicative of an active cell state. The tgev was found between microvilli, in the cytoplasmic vesicles of M cells and microvillus-covered epithelial cells in the de, and in the cytoplasm of macrophages and lymphocytes and some degenerated cells of unidentified origin in the domes of the aln. The virus was also commonly found in cytoplasmic vesicles of macrophages and degenerated cells in the intestinal lumen near the base of the dome of the aln.
Lymphoscintigraphy in canine mammary neoplasia
Authors: Norris Alan M. , Harauz George , Ege Güneş N. , Broxup Brian , Valli V. E. O. , Leger Luc
Published: February 2025

Radionuclide lymphoscintigraphy, using an interstitial injection of 99mTcSb2S3 colloid, provided scintigraphic images of diagnostic quality of lymph nodes draining the mammary glands in 4 clinically normal dogs and in 13 dogs with mammary neoplasia. This simple, noninvasive technique demonstrated anatomic variants of the canine lymphatic system. Lymphoscintigraphy correctly identified 100% of all lymph nodes with metastases and 82% of lymph nodes free of metastases, as determined by histologic findings.
Effects of alpha chymotrypsin on the canine eye
Authors: Barrie Kathleen P. , Gelatt Kirk N. , Gum Glenwood G. , Samuelson Don A.
Published: February 2025

Injection of 150, 500, or 750 U of α chymotrypsin into the posterior chamber of clinically normal Beagles resulted in changes in intraocular pressure and iridocyclitis. In the 6 eyes treated with 500 or 750 U, lens subluxation occurred in 4 eyes, retinal detachment in 1 eye, retinal degeneration in 1 eye, and optic nerve degeneration in 6 eyes. Scanning electron microscopic changes included dose-related zonu-lolysis and zonulary remnants within the aqueous humor outflow pathways. Ultrastructural changes by transmission microscopy of the optic nerve degeneration revealed loss of axoplasm and organelles and disruption of the myelin sheaths. Retinal and optic nerve changes may represent the direct toxic effects of α chymotrypsin and/or the indirect effects of increased intraocular pressure.
Experimental infection of lambs with bovine respiratory syncytial virus and Pasteurella haemolytica: Pathologic studies
Authors: Al-Darraji A. M. , Cutlip R. C. , Lehmkuhl H. D. , Graham D. L.
Published: February 2025

Nineteen 4-week-old, colostrum-deprived lambs were transtracheally inoculated with respiratory syncytial virus (rsv), Pasteurella haemolytica biotype A serotype 1, or rsv and P haemolytica. Pneumonic lesions were more frequent, more extensive, and more severe in lambs inoculated with rsv and P haemolytica than in lambs inoculated with either agent alone. Lesions were seen in 2 of 4 lambs inoculated with P haemolytica alone, in 3 of 4 lambs inoculated with rsv alone, and in 11 of 11 lambs inoculated with rsv and P haemolytica. Grossly, lambs given P haemolytica alone had fibrinous pleuritis and pneumonic lesions with hemorrhagic and necrotic centers which involved approximately 14% of the lung surface. Lambs inoculated with rsv alone had multifocal areas of consolidation and hemorrhage that involved 5% of the lung surface. Lambs in 2 groups inoculated with rsv and P haemolytica had lesions characteristic of both agents over 15% to 21% of the lung surface. Histologically, P haemolytica alone caused acute fibrinous pneumonia with necrosis of the lung parenchyma and fibrinous pleuritis; rsv alone caused interstitial pneumonitis, bronchiolitis, and hemorrhage. In combination, the agents caused interstitial pneumonitis and severe exudative pneumonia with focal necrosis and hemorrhage.

Lesions seen in lambs given rsv and P haemolytica or in lambs given P haemolytica alone were grossly and histologically similar to those seen in naturally occurring cases of acute pneumonic pasteurellosis. Seemingly, the virus caused a lesion that compromised the lungs and thus permitted P haemolytica to become established and to produce a more severe pneumonic lesion than it could produce alone.
Abnormal spermatozoa, testicular degeneration, and varicocele in a ram
Authors: Ott R. S. , Heath E. H. , Bane A.
Published: February 2025

A 4-year-old Corriedale ram, with a history of infertility, had 50% abnormal acrosomes in the ejaculate resembling knobbed spermatozoa. Electron microscopic profiles of the apical segment of the affected acrosomes revealed a membrane-enclosed inclusion or cyst filled with particulate matter. The abnormal acrosomes were combined with a high prevalence of other degenerative changes such as head abnormalities, proximal droplets, and loose heads. Spermatozoa were examined from 9 ejaculates collected over an 8-month period. Abnormal acrosomes decreased to 5% after 4 months, but increased to 83% a month later. Examination of the testes after castration revealed bilateral varicocele and degeneration of seminiferous epithelium.
Intestinal, pulmonary, and serum antibody responses of feeder pigs exposed to transmissible gastroenteritis virus by the oral and the oral-intranasal routes of inoculation
Authors: Sprino Phillip J. , Ristic Miodrag
Published: February 2025

Specific antibodies against transmissible gastroenteritis (tge) virus produced as a result of oral and oral-intranasal viral exposure of feeder pigs were isolated by molecular sieve column chromatography of lung wash, intestinal fluid, and serum samples. Selected fractions were analyzed for neutralizing antibody activity. Oral inoculation gave a predominantly immunoglobulin (Ig) G antibody response in lung wash and serum, as compared with the response in intestinal fluid in which neutralizing antibody activity was found in the IgA-containing fractions. Oral-intranasal inoculation produced a predominantly IgA antibody response in intestinal fluid. Lung wash contained IgA and IgG antibody, and serum antibody consisted primarily of IgG class of Ig. Neutralizing antibody (IgA, IgG, IgM) from the lung wash, intestinal fluid, and serum samples persisted beyond 56 days after oral and oral-intranasal viral exposures.

The virus-shedding period in feces was 1 to 7 days after oral or oral-intranasal inoculation of feeder swine with virulent tge virus. However, tge virus was reisolated from lung and intestinal tissue for as long as 42 and 56 days, respectively.
Control of psoroptic scabies on calves with ivermectin
Authors: Meleney William P.
Published: February 2025

Eleven Hereford or Angus-cross calves slightly to severely infested with common scabies mites (Psoroptes ovis) were treated with 22,23-dihydroavermectin B1a (ivermectin) at dosages given subcutaneously (sc)—300 μg/kg; orally—400 μg/kg; or im—50, 100, or 200 μg/kg. At 14 days after treatment, live mites were not found on any of the calves treated sc or im, but live mites were found on all of the orally treated calves at 14 days and on 1 of them at 28 days after treatment. Four nontreated calves retained their mite infestations during the course of the im test. Biting lice (Bovicola bovis) were eliminated from 1 calf treated sc, but not from calves treated im. Ear ticks (Otobius megnini) were not noticeably affected.
Histogenesis of the reticular groove of the buffalo (Bubalus bubalis) stomach
Authors: Panchamukhi B. G. , Srivastava H. C.
Published: February 2025

Histogenesis of the reticular groove (sulcus reticuli) of the buffalo (Bubalus bubalis)was observed from primordial stage to birth. The epithelium of the reticular groove was considered early embryonic until a crownrump (cr) length of 2.2 cm, and was uniformly distributed at cr 2.2 cm; superficial and basal zones developed by cr 3.2 cm. At cr 10.5 cm, the basal zone in the floor evaginated and formed longitudinal folds. At cr 25.5 cm, the basal zone in the bps evaginated and formed papillae. The core of the longitudinal folds and papillae was formed by the lamina propria, muscularis mucosae, and submucosa. Keratinization was seen at cr 50.5 cm, and the epithelium was stratified squamous epithelium with keratinization, similar to that of the adult buffalo. The floor and lip had a single layer of muscle. A small oblique muscle layer was also found in the concavity of the lip. The correlation between structure and function of the reticular groove is discussed.
Concentrations of plasma C-terminal immunoreactive parathyroid hormone in the standardized research Beagle
Authors: Jorch U. M. , Anderson C. , Delaquerriere-Richardson L. F. O. , Cook M. A.
Published: February 2025

To assist in studies of the bone remodeling process, determination was made of plasma concentrations of C-terminal immunoreactive parathyroid hormone in the healthy Beagle dog. Blood samples were obtained from 34 Beagles ranging in age from 2 to 25 months. The values were between 10 and 82 μlEq/ml, with a mean of 36.72 μlEq/ml.
Colonic anastomosis: Evaluation of an end-to-end crushing and inverting technique
Authors: Richardson Daniel C. , Duckett Kermit E. , Krahwinkel D. J. , Shipman L. W.
Published: February 2025

Two anastomotic techniques of the colon were evaluated in the dog. An end-to-end simple interrupted crushing suture pattern and an end-to-end interrupted inverting (Connell) suture pattern were used with 3-0 polyglycolic acid as the suture material.

Results of clinical evaluations, lasting 28 days, identified no differences between the 2 techniques. Postoperative complications were not encountered during the 28 days. Daily monitoring of hematologic values and temperature demonstrated normal stress responses to the surgical insult, but differences were not noted between the surgical groups.

Evaluations of adhesion formation at necropsy (28th day) showed no statistical difference between the 2 groups, nor were the hematologic values associated with peritonitis and resulting adhesion formation. Adhesions were minimal and did not grossly interfere with mechanical function of the intestines.

Stenosis was marked with the inverting suture pattern, accounting for an average 63% loss of the lumen diameter at the anastomotic site. The crushing pattern averaged 30% loss of diameter. Even though the lumen size at the anastomoses was greatly reduced with the inverting pattern, clinical significance between the 2 groups was not noted.

Bursting pressure studies at postsurgical day 28 showed that the inverting suture pattern achieved equal normal intestinal strength, whereas the crushing technique was significantly weaker. All but 3 specimens burst on the anastomotic line, and all burst on the antimesenteric border.

Histopathologic evaluations at postsurgical day 28 indicated that the end-to-end crushing pattern had less inflammatory response at the anastomosis. Mucosa bridged the anastomotic site and the remaining layers were aligning themselves with minimal fibrous tissue proliferation. The inverting pattern maintained a bud of granulation tissue at the anastomotic site. The mucosa did not bridge this area. Inflammatory cells and fibrous tissue proliferation at the anastomotic site were marked in comparison to the crushing pattern.

Despite these findings, neither technique was proved to be clinically superior in conditioned research dogs.
Oval lipid corneal opacities in Beagles: Ultrastructure of normal Beagle cornea
Authors: Morrin Lynne A. , Waring George O. , Spangler William
Published: February 2025

The ultrastructure of normal Beagle cornea was similar to the human cornea, except the Beagle lacked an anterior limiting lamina (Bowman's layer) and banding in the anterior portion of the posterior limiting lamina (Descemet's membrane). The epithelium was an average of 19 cells thick with 3 basic types: squamous, polygonal, and basal. The subepithelial stroma with a mean thickness of 9 μm was hypocellular, and the bundles of collagen were randomly oriented. The majority of the stroma consisted of closely packed, parallel collagen lamellae interspersed with keratocytes and occasional nerve fibers. The posterior limiting lamina was homogeneous and thick with increasing age. The endothelial cells formed a monolayer and had apical tight junctions.
Comparison of aqueous porcine ACTH with synthetic ACTH in adrenal stimulation tests of the female dog
Authors: Feldman E. C. , Stabenfeldt G. H. , Farver T. B. , Addiego L. A.
Published: February 2025

The adrenocortical (plasma corticosteroid) responses in female dogs given porcine acth in gelatin (1-39 amino acid sequence) and synthetic acth (1-24 amino acid sequence) were compared. Sixteen dogs were used. Each dog underwent 4 different acth stimulation studies, these being done with a 4- to 8-week interval. The studies in each dog included injections of 2 doses of porcine acth—2.2 IU and 4.4 IU/kg of body weight—and of 2 doses of synthetic acth—0.25 mg/dog and 0.50 mg/dog. The dogs were arbitrarily allotted to 4 groups, each group being subjected to a given sequence of stimulation studies.

The purpose in this project was to determine whether the established methods for synthetic and porcine acth stimulation tests had similar results. Statistical analysis of the 4 stimulation methods revealed no significance (P > 0.05) in the resting or poststimulation plasma corticosteroid concentrations. Thus, it was concluded that either recommended method using acth (porcine acth at 2.2 IU/kg or synthetic acth at 0.25 mg/dog) causes maximal secretion of adrenocortical reserve. Either acth preparation, using the established method, can be used interchangeably.
Controlled tests of fenbendazole against migrating Strongylus vulgaris in ponies
Authors: Slocombe J. O. D. , McCraw B. M.
Published: February 2025

Sixteen pony foals were reared worm-free and inoculated with Strongylus vulgaris. On day 7 after inoculation, 12 ponies were given a fenbendazole 10% suspension at dose rate of 50 mg/kg of body weight by stomach tube. On day 8 after inoculation, 8 of these ponies were given the 2nd treatment of the anthelmintic and on day 9, 4 of these ponies were given the 3rd treatment. (The other 4 of the 16 ponies were given only tap water, as controls.) The ponies were necropsied at death or on day 28 after inoculation. Fenbendazole was effective in minimizing the appearance of clinical signs associated with acute arteritis and was highly efficacious in eliminating early 4th-stage S vulgaris larvae in ponies treated for 3 consecutive days (ie, days 7, 8, and 9). After administration of the anthelmintic, clinical signs of toxicosis were not observed.
In vitro susceptibility of selected isolates of Brucella abortus to penicillin
Authors: Stinebring Warren R. , Kunkel John R.
Published: February 2025

Brucella abortus isolates (n = 134) from 38 dairy herds in Vermont, Florida, and Canada exhibited 2 growth patterns on medium containing 5 U of penicillin/ml. The B abortus isolates from 7 herds in Vermont were always susceptible to the antibiotic at that concentration. Eleven of 12 isolates from 1 herd in Florida and 25 isolates (biotypes 1 and 4) from 30 Canadian herds grew at ≥ 5 U of penicillin/ml, as determined using a gradient plate method. Penicillin susceptibility may be of value in identifying the source of infections in cattle.
Leukocyte migration-inhibition responses of nonvaccinated and vaccinated heifers to experimental infection with Brucella abortus
Authors: Dorsey T. A. , Deyoe B. L.
Published: February 2025

The leukocyte migration agarose technique was used to show the leukocyte migration-inhibition responses of nonvaccinated and vaccinated heifers to experimental infection with Brucella abortus. All heifers had increased leukocyte migration inhibition after exposure to B abortus. Nonvaccinated heifers which aborted had the highest responses. The responses of the vaccinated heifers were significantly (P < 0.01) lower than those of nonvaccinated heifers. None of the vaccinated heifers aborted.
Effect of intra-articular injection of orgotein and saline solution on equine synovia
Authors: Wagner A. E. , Mcllwraith C. W. , Martin G. S.
Published: February 2025

Orgotein was injected into the right intercarpal joint of each of 8 horses; the corresponding left joint was left alone (not injected) or was given an injection of normal saline solution. Injection with orgotein caused a transient, marked inflammatory response, evidenced by clinical signs and by increased leukocytes and total protein in the synovia (synovial fluid). Leukocyte numbers and total protein concentration were increased (P < 0.010) in the orgotein-injected joints within 24 hours. However, saline solution alone also elicited a marked inflammatory response, manifested by increased leukocyte count and total protein concentration. By 7 days, leukocyte and total protein values had returned to approximately base line in all joints.
Renal function of the pony and the horse
Authors: Zatzman M. L. , Clarke L. , Ray W. J. , Garner H. E. , Traver D.
Published: February 2025

Simultaneous renal clearances of inulin (CIN), p-aminohippurate (CPAH), and creatinine (CCR) were measured in hydrated mares (6 ponies and 2 horses). The CIN and CPAH were determined during steady-state infusion at 3 different infusion rates. A 6-fold change in plasma in concentration did not produce alteration in CIN, nor was there a difference between the ponies and horses (P > 0.2). The overall average (mean ± sem) was 190.6 ± 5.89 ml · min-1 · 100 kg of body weight-1. There was no difference noted between simultaneous CIN and CPAH. Clearance of pah remained essentially constant during the change in plasma pah from 0.33 mg/dl to 5.27 mg/dl. The extraction ratio of pah for the nonanesthetized pony was 0.966. Effective renal plasma flow (CPAH) of the pony exceeded that of the horse.
Long-term effect of Bordetella bronchiseptica infection in neonatal pigs
Authors: Underdahl Norman R. , Socha Thomas E. , Doster Alan R.
Published: February 2025

A total of 62 gnotobiotic pigs were inoculated with Bordetella bronchiseptica at 7 days of age. There were 25 noninoculated controls. Thirteen of the inoculated pigs were killed and 6 pigs which died were examined between 3 and 5 weeks after inoculations were done (group A). Of these 19 pigs, 16 had severe pneumonia and B bronchiseptica was isolated from the lungs of 17. The turbinates in most of the pigs appeared to have some atrophy.

Four other pigs died of pneumonia after they were transferred to the floor in isolation rooms, and 9 inoculated pigs were examined at necropsy at about 112 days of age (group B). Bordetella bronchiseptica was isolated from 8 of the latter 9 pigs, and 7 of the pigs had pneumonic lesions. The turbinates all appeared normal.

Thirty inoculated pigs (group C) were killed at 180 days of age. Of these, 22 had pneumonic lesions. Bordetella bronchiseptica was reisolated from the turbinates of 2 of 30 pigs, although the turbinates in all appeared normal.

The noninoculated controls examined at necropsy at 3 to 5 weeks, 112 days, and 180 days of age did not have any pulmonic lesions, and their turbinates appeared normal.

The inoculated pigs killed at 112 days of age gained an average of 0.25 kg/day, and the control pigs gained 0.31 kg. At 180 days of age, the inoculated pigs had gained 0.41 kg/ day and the controls, 0.49 kg.

Bordetella bronchiseptica infection in susceptible pigs can cause a severe pneumonia which can persist and reduce the growth rate.
Antibodies to spotted fever-group rickettsiae in dogs and prevalence of infected ticks in southern Connecticut
Authors: Magnarelli Louis A. , Anderson John F. , Philip Robert N. , Burgdorfer Willy
Published: February 2025

Blood samples and ticks were obtained from dogs to assess canine exposure to spotted fever-group (sfg) rickettsiae during 1978-1980 in southern Connecticut. Of the 1,576 dog sera screened by microimmunofluorescence, 174 (11.0%) contained specific antibodies at titers ≥ 1:64 against Rickettsia montana (n = 34), R rickettsii (n = 31), R rhipicephali (n = 19), or the unclassified 369-C rickettsia (n = 90). End points ≥ 1:8,192 to R rickettsii and to R rhipicephali were recorded for 6 and 3 sera, respectively. Seropositivity rates from southwestern and southeastern Connecticut were similar (about 11%), with positive sera obtained from each region in nearly all months of the investigation. Rates were between 10% for dogs 2 to 7 years old and 14% for those ≥ 8 years. Eight of 629 Dermacentor variabilis, 1 of 18 Ixodes dammini, and 2 of 3 Amblyomma americanum were positive by direct immunofluorescence for sfg rickettsiae. Thirteen D variabilis contained unidentified, long, bacillus-like organisms that differed from the short, ovoid (coccal) forms typical of the spotted-fever agent, R rickettsii. With the exposure to infected ticks and production of type-specific antibodies against at least 4 sfg antigens, dogs may serve as suitable enzootic or epizootic indicators of rickettsial activity.
Ultrastructural changes in livers of young and aging rats exposed to methylated benzenes
Authors: Bowers Daniel E. , Cannon M. Samuel , Jones Daniel H.
Published: February 2025

Ultrastructural examination was conducted on livers of young rats which were given (intraperitoneal injection) several methylated benzenes (73 mg/kg of body weight) for 3 consecutive days and on livers of aging rats (12 to 19 months old) which were fed methylated benzenes in the diet (200 mg/1,000 g of feed) for periods of 1, 2, 3, and 6 months. The young animals demonstrated white, raised, nodular lesions along the free margins of the liver. The lesions in young animals consisted of lipid droplets surrounded by macrophages and fibroblasts. Some fibroblasts in these lesions appeared to be active in collagen synthesis. Mast cells and eosinophils also occurred in the lesions. Hepatocytes in these young animals appeared morphologically normal.

In contrast, hepatocytes in the aging rats developed 2 types of vacuoles. The 1st type of vacuole was bound by a double-unit membrane—the outer unit membrane possibly derived from smooth endoplasmic reticulum; it contained a mottled, globular, electron-lucent material. The 2nd type of vacuole was peripherally located in hepatocytes, was single membrane-bound, and occasionally was observed opening into the space of Disse (spatium perisinusoideum). Our observations indicated that acute exposure (3 days) to at least some methylated benzenes does not cause ultrastructurally observable abnormalities in hepatocytes of young rats, but chronic oral ingestion of some can cause formation of vacuolar structures in aging rat hepatocytes.
Prevalence and distribution of Haemophilus somnus in the male bovine reproductive tract
Authors: Humphrey J. D. , Little P. B. , Stephens L. R. , Barnum D. A. , Doig P. A. , Thorsen J.
Published: February 2025

“Haemophilus somnus” was isolated from 77% of 31 reproductive tracts of bulls from an Ontario slaughterhouse. Identification of H somnus was based on morphologic and cultural characteristics and on fluorescent antibody and immunodiffusion tests, using antisera prepared against a known pathogenic encephalitic isolate of H somnus. The infection rate and distribution of H somnus within the tract were as follows: preputial orifice—71% preputial cavity—71%; urinary bladder—26%; accessory sex glands—19% and ampulla of ductus deferens—10%. Isolates were not obtained from the testes or epididymides. On 2 occasions, H somnus was isolated in pure culture from the preputial cavity. A higher prevalence of infection was found in young bulls. There were no differences found in infection rates between breeds. Differences in hemolytic activity and minor antigenic variation between isolates indicated that a series of biotypes within the species H somnus may exist. The study indicates that organisms presently identified as H somnus may normally form part of the flora of the bovine prepuce and that dissemination from the male bovine reproductive tract is one possible means of infection in H somnus-associated diseases. The pathogenic significance of genital isolates of H somnus awaits further study.
Effect of glucose administration on equine fasting hyperbilirubinemia
Authors: Gronwall Ronald , Engelking Larry R.
Published: February 2025

The effects of several treatments and their routes of administration on the reduction of hyperbilirubinemia in 9 pony mares after a 3-day fast were studied. Treatments were as follows: glucose given at doses of 1.2, 2.4, and 3.7 mg/min/kg of body weight; refeeding the base-line diet; feeding straw; and iv administration of taurocholic acid at a dosage of 0.07 μmol/min/kg.

The 3 glucose dosages were each given by 3 different routes: iv, intraduodenal, and intragastric. The smallest dosage of glucose given by iv route reduced the plasma bilirubin concentration only 7%, even though other measured values associated with fasting returned toward their base line; increased free fatty acid concentration was reduced by 50%; plasma insulin increased above base-line values. Except for the smallest glucose dose given by iv route, the effects of the routes of administration (iv < intraduodenal < intragastric) and of the doses of glucose were not significantly different.

Taurocholic acid (given iv) was ineffective in reducing the plasma fasting bilirubin concentration. Refeeding the base-line diet reduced the hyperbilirubinemia by 66% in 12 hours, which was a significantly greater reduction than the effect of all other treatments except the largest dose of glucose given by intragastric route. Feeding straw was less effective than refeeding, causing only about a 30% reduction.
Carboxyhemoglobin values in swine relative to carbon monoxide exposure: Guidelines for monitoring animal and human health hazards in swine-confinement buildings
Authors: Donham Kelley J. , Carson T. L. , Adrian Burton R.
Published: February 2025

Miniature pigs were exposed, in an environmental chamber, to 55 mg of CO/m3 of air, 110 mg/m3, 220 mg/m3, or 330 mg/m3. Blood samples were taken from the swine every hour over an exposure period of 6 or 8 hours. After the pigs were removed from the chamber, blood samples were taken every 30 minutes for an additional 3 hours. The blood samples were measured by spectrophotometry for the amount of carboxyhemoglobin (COHb).

On exposure to CO, the COHb values in the pigs increased in a linear fashion during the first 2 hours, then began to level off, reaching a peak concentration at 6 to 8 hours. The percentage of COHb in the blood after 6 hours' exposure to the different amounts of CO were as follows: 55 mg/m3 - 5%, 110 mg/m3 - 10.5%, 220 mg/m3 - 20%, and 330 mg/m3 — 27.2%. There was a linear relationship between the amount of CO exposure and the peak blood value of COHb.

The present data provide guidelines for the use of COHb measurement in swine as a means to monitor the environment in swine-confinement buildings for potentially dangerous amounts of CO for swine and persons and to aid in the diagnosis of CO-induced perinatal disease in swine.
Failure of swine influenza virus to cause transplacental infection of porcine fetuses
Authors: Brown T. T. , Mengeling W. L. , Pirtle E. E.
Published: February 2025

Nine pregnant gilts, seronegative to swine influenza virus (siv), were inoculated by various routes with different quantities and strains of siv. Fetuses which were collected from the gilts at different times after inoculations were done and newborn pigs were examined for evidence of transplacental siv infection. Gilts remained clinically healthy after virus inoculation, and evidence of siv infection was not found in any of the fetuses or newborn pigs.
Effect of peripheral anosmia on dogs trained as flavor validators
Authors: Houpt Katherine A. , Davis Peter P. , Hintz Harold F.
Published: February 2025

The importance of olfaction in perception of flavor by flavor-validating dogs was studied. The flavor-validation technique is widely used by pet food manufacturers to determine if a given formula is perceived by dogs as having the flavor of a specific meat. Five Beagles were trained as flavor validators; 2 dogs were trained to select beef and 3 to select lamb from a panel of 4 meats. When the dogs had been trained to select the correct meat on 100% of the trials, they were made anosmic. Reversible peripheral anosmia was produced in the dogs by inflating a cuff on a surgically implanted tracheostomy tube. When the cuff was inflated, air entered the trachea via the tracheostomy tube, rather than via the nasal cavity, and the percentage of correct choices on the flavor-validating test fell to 62 ± 14%. When the tracheostomy tubes were removed, performance returned to 100% correct.

The nasal cavities of 3 dogs were infused with zinc sulfate to produce a more complete and longer-lasting anosmia. The percentage of correct choice on the flavor-validation test fell to 24 ± 5%. These findings indicate that the flavor-validation test is based primarily on one sensory modality, that of olfaction; therefore, formulas selected by flavor-validating dogs may smell similar to the specific meat, but do not necessarily taste similar to that meat.
Proliferative colitis in ferrets
Authors: Fox J. G. , Murphy J. C. , Ackerman J. I. , Prostak K. S. , Gallagher C. A. , Rambow V. J.
Published: February 2025

During a 4-month period, 31 of 156 ferrets (Mustela putorius) in a biomedical research program developed protracted diarrhea. Clinical signs were green mucohemorrhagic fecal material, partially prolapsed rectum, anorexia, body weight loss, and dehydration. Nine of the affected animals were necropsied. On gross examination, the descending colon was grossly thick and histologically characterized by marked proliferation of the mucosa, relatively few goblet cells, mixed inflammatory cell infiltrate, and penetration of the mucosal glands through the muscularis mucosa into the submucosa and tunica muscularis. Campylobacter fetus subsp jejuni was isolated from 6 of 9 ferrets with proliferative colitis. Warthin-Starry stained sections of hyperplastic colon revealed large numbers of organisms in the apical portion of epithelial cells, and organisms similar to Campylobacter spp were observed by electron microscopy in hyperplastic colonic epithelium. The proliferative colitis in the ferret is compared with the pathologic and bacterial features of similar intestinal proliferative diseases in swine and hamsters.
Live temperature-sensitive equine influenza virus vaccine: Generation of the virus and efficacy in hamsters
Authors: Brundage-Anguish Lynne J. , Holmes Dorothy B. , Hosier Nannette T. , Murphy Brian R. , Massicott Judith G , Appleyard Geoffrey , Coggins Leroy
Published: February 2025

Temperature-sensitive (ts) reassortants of an equine influenza virus, subtype A-l, were produced by mating a human influenza ts donor virus with an equine influenza A/Cornell/16/74 wild-type virus and by isolating a ts reassortant virus possessing the equine hemagglutinin and neuraminidase surface antigens. Two equine ts reassortant clones, 8B1 and 71A1, were produced which had an in vitro shutoff temperature for plaque formation of 38 and 37 C, respectively. The human ts donor virus had ts mutation(s) on the polymerase 3 (P3) and nucleoprotein genes so that a ts equine reassortant virus could have either or both of these ts genes. It was found by complementation analysis that reassortant clone 8B1 had a ts lesion on the P3 gene and clone 71A1 had ts lesions on the nucleoprotein and P3 gene. An analysis of the parental origin of the genes in each ts equine reassortant virus indicated that clone 8B1 received 6 of its 8 genes and clone 71A1, 3 of its 8 from the equine parent virus, the remainder genes being from the human ts donor virus. The growth of both clones was restricted in the lungs of hamsters, but similar to that of the equine wild-type virus in the nasal turbinates. Each virus isolate obtained from the hamster's lungs or nasal turbinates retained the ts phenotype. These findings form the basis for further evaluation of the equine ts reassortant viruses for their level of attenuation and immunogenicity in horses
Metabolic and cellular profile testing in calves maintained under feedlot conditions: Protein fractions and lactate dehydrogenase isoenzymes—Changes over time
Authors: Lauerman L. H. , Ruppanner R. , Norman B. B. , Adams C. J. , Farver T. B.
Published: February 2025

Mean concentrations for total serum protein and serum protein fractions, and mean activities for total lactate dehydrogenase (ldh) and ldh isoenzymes were determined in 114 crossbred yearling cattle during a 56- day feeding trial. These values were to be used as predictors of performance (weight gain). The mean total serum protein concentration on day 0 was high (7.27 g/dl), reached a low on days 7 and 14 (6.47 and 6.50 g/dl), and then equilibrated toward the end of the study. The mean concentration for the albumin fraction also reached a low on days 7 and 14 (2.83 and 2.84 g/dl) and then increased, remaining steady until termination of the feeding trial. The α-, β-, and γ-globulin fractions fluctuated throughout the study. The mean for total ldh activity peaked on day 21 (1,363 IU) and then remained relatively constant through day 56. Mean serum activities for the ldh3 activity peaked on day 7 (27%) and then decreased progressively to day 56 (17%). The overall trend for ldh4 and ldh5 activities seemed to be a steady increase.
Bluetongue infections in Louisiana cattle
Authors: Fulton Robert W. , Nicholson S. S. , Pearson Nancy J. , Potter Marylou T. , Archbald L. F. , Pearson J. E. , Jochim M. M.
Published: February 2025

Bluetongue virus (btv) serotype 17 was isolated from cattle with clinical signs of bluetongue disease during 1978 and 1979 epizootics. Bovine sera from 6 herds located in an epizootic region were examined in 1979 for antibodies, using an immunodiffusion (id) test. Of 300 sera, 164 (54.7%) were seropositive.

Sera from statewide surveys of Louisiana cattle in July to August 1980 and December 1980 to January 1981 were tested for btv antibodies, using the id test. Fifty-eight of 70 herds (82.9%) and 164 of 597 (27.5%) individual cattle tested in July to August 1980 were seropositive. Fifty-four of 63 (85.7%) herds and 170 of 600 (28.3%) individual cattle tested in December 1980 to January 1981 were seropositive. Significant differences (P < 0.01) were found in the seropositive rates between the various geographic regions of the state during each survey.

Adult breeding-age cattle in 3 sentinel herds were tested for btv antibodies beginning in 1976 and continuing through January 1981. During this interval, the seropositive rate in 2 of 3 herds was increased. Also, individual cattle in all 3 of these herds converted from seronegative to seropositive, indicating exposure during a particular interval for each herd. The age distribution of seropositive cattle in a dairy indicated that 2-year-old cattle had a seropositive rate comparable with that of older animals in the herd, suggesting that the 2-year-old animals had been exposed to a btv before they entered the breeding herd.
Plasma α- and β-mannosidase activities in caprine β-mannosidosis
Authors: Cavanagh Kevin , Dunstan Robert W. , Jones Margaret Z.
Published: February 2025

Plasma α- and β-mannosidase activities were measured in goats with β-mannosidosis, a recently discovered, inherited deficiency of the glycohydrolase β-d-mannosidase. Plasma β-mannosidase activity in the affected animals was zero at 1 and 4 weeks after they were born. Enzyme values of age-matched, unaffected goats were between 66 and 222 nmol/hr/ml of plasma, α-Mannosidase activities were similar in both affected and unaffected animals. This investigation indicates that deficiency of plasma β-mannosidases activity may be diagnostic of β-mannosidosis.
Metabolic and cellular profile of wether goats: Protein fractions and lactate dehydrogenase isoenzymes—Reference values
Authors: Blackwell J. G. , Libby David W.
Published: February 2025

Blood serum concentrations of electrolytes; mineral, serum protein, and biochemical components; serum lactate dehydrogenase (ldh) activity; and blood cellular components were determined in 8 wether goats over a 59-day feeding period. The blood was collected on 6 sampling days, and the blood cellular components were analyzed on collection days. The biochemical components were analyzed from frozen samples approximately 3 weeks after collection. The serum protein fractions and ldh isoenzymes were separated electrophoretically from frozen samples. The purpose was to determine the variability and changes of these values, using sampleday intervals over the feeding period.

The blood serum concentrations of many of the biochemical and blood cellular components that were measured or calculated varied considerably, showing fluctuations over some portion of the period and ending with an erratic peak at period’s end.

The wbc count, neutrophil, and band neutrophil values were sharply decreased on sampling days 24 and 35, followed by fluctuations over the last half of the period.

Mean percentage concentrations for serum protein fractions for the feeding period were as follows: albumin, 47.13; α-globulin, 11.07; β-globulin, 15.78; and γ-globulin, 27.82. The values for ldh isoenzymes were ldh1 42.46; ldh2, 4.34; ldh3, 32.31; ldh4, 4.9; and ldh5, 11.64. Mean values of the protein fractions are compared with published standard reference values. The values for serum protein fractions and ldh isoenzymes in the present study can be used in similar studies for reference values.
Frequency of bluetongue and bovine parvovirus infection in cattle in South Carolina dairy herds
Authors: Barnes Michael A. , Wright Robert E. , Bodine Ashby B. , Alberty Craig F.
Published: February 2025

A survey of South Caroline dairy cattle in 12 commercial herds was conducted, using serologic testing to determine the frequency and impact on reproduction of bluetongue (bt) and bovine parvovirus (bpv) infections. Results of the study of serum antibody titers and dairy cattle health records indicated that the majority of the cattle surveyed was adequately protected against the major reproductive tract diseases through vaccination programs. The frequency of reproductive dysfunction was common in vaccinated herds, however. Six of the 12 herds in the survey had cattle which were bt serotest reactors, although total numbers of these reactor cattle were relatively small. Further, reproductive performance of reactor cows indicated that bt was of little consequence and was not associated with reproductive problems. All herds contained bpv serotest reactors and the latter comprised 59.7% of the total number of cows surveyed. The bpv seroreactor cows were commonly associated with the group of reproductive problem cows which experienced higher rates of embryonic mortality and more services per conception than did nonreactor cattle. The results of the survey emphasize the need for continued investigation and efforts to control bt, and especially bpv infection, in dairy cattle.