bluuebunny/crossref_metadata_2025 huggingface dataset:
Inhibition of Lymphocyte Blastogenesis by Sera from Cows with Lymphoma
Authors: Jacobs R. M. , Valli V. E. O. , Wilkie B. N.
Published: February 2025

The sera from cows with lymphoma inhibit the blastogenesis of normal lymphocytes. The inhibitory sera were partially characterized. Twenty of 34 sera from cows with lymphoma caused inhibition, whereas 3 of 25 sera from healthy animals were inhibitory. Sera from 15 cows with various inflammatory conditions did not cause inhibition. Seventy-four cows were tested for responsiveness to phytohemagglutinin, and of this group, the stimulation indices of 25 animals which had antibody to the bovine leukemia virus did not differ from the remainder of the group. The inhibitory substance: (a) was heat stable at 56 C for 30 minutes, (b) was not overcome by the addition of phytohemagglutinin, (c) was active in a manner that was proportional to the concentration of serum in the culture media, (d) was not lymphocytotoxic at a concentration which was profoundly inhibitory to blastogenesis, (e) was found in the first peak eluted from a Sephadex G-200 column, (f) was nonspecifically active because it inhibited the blastogenesis of a panel of lymphocytes from healthy animals, (g) was present in 59% of cows with lymphoma in the terminal stages of disease, (h) was rarely present in healthy cows or cows with inflammatory conditions, and (i) was not associated with bovine leukemia virus infection in the absence of tumor development.
Effect of Hyaluronic Acid in Naturally Occurring and Experimentally Induced Osteoarthritis
Authors: Auer J. A. , Fackelman G. E. , Gingerich D. A. , Fetter A. W.
Published: February 2025

Effect of intraarticular injections of hyaluronic acid was evaluated in two groups of horses, using force plates to assess quantitatively the degree of lameness observed. In six horses, chip fractures were created surgically on the dorsomedial aspects of both radial carpal bones. After the horses were trained for 30 days, 40 mg of hyaluronic acid was injected intraarticularly into the limb showing the greater degree of lameness. Horses were worked for 2 more weeks and then were evaluated. A highly significant (P < 0.01) increase in weight bearing on the treated limb was observed.

Ten horses with clinical unilateral front limb lameness, involving a single joint, also were treated with 40 mg of hyaluronic acid. The day after the injection, the horses resumed training and were examined 2 weeks later. At that time, the horses were free from observable lameness, and this observation was corroborated by force plate data. According to their trainers, the horses’ performance improved markedly after the injection and remained improved.

Seemingly hyaluronic acid was beneficial when injected into the arthritic joints of these two groups of horses.
Experimental Transmission of African Swine Fever Virus by Omithodoros coriaceus an Argasid Tick Indigenous to the United States
Authors: Groocock C. M. , Hess W. R. , Gladney W. J.
Published: February 2025

Three ticks, indigenous to the United States, were assessed for their ability to maintain and transmit African swine fever virus (asfv). Amblyomma americanum and A cajennense adults and nymphs maintained virus for 4 to 7 days after engorging on infected swine blood; however, virus was not carried through the subsequent molt of nymphs and it was not transmitted vertically to the eggs and larvae of the infected females. On refeeding of the ticks, infection was not transmitted to healthy swine. Ornithodoros coriaceus adult females also did not show transovarial transmission of two strains of asfv. Nymphs, however, maintained virus for 77 to 118 days through a molting stage and transmitted one strain of the virus (Lisbon 60) to healthy swine.
A Simple Intestinal Cannula for Swine
Authors: Gargallo J. , Zimmerman D. R.
Published: February 2025

A T-cannula was designed for placement in the gastrointestinal tract of pigs used for nutritional studies. It was made from available and inexpensive polyvinylchloride plumbing fittings. The main advantages of the cannula are (1) light weight (32 g), (2) good tolerance by the animals, (3) short projection from the body wall, (4) minimal leakage, and (5) patency for several months. The caudal part of the ilea of ten pigs was cannulated with satisfactory results. Macroscopic alterations of the gastrointestinal tract were not observed when the animals were euthanatized.
Physiologic Features of the Canine Esophagus: Effect of Modified Heller's Esophagomyotomy
Authors: Hoffer R. E. , MacCoy D. Μ. , Gaynor F. , Moraff H. , Aron D. , Quick C. B. , Law K.
Published: February 2025

The effects of the modified Heller's esophagomyotomy on function of the lower esophageal sphincter in the dog were studied. In normal dogs, this surgical procedure produced a less competent lower esophageal sphincter that still maintained the ability to prevent esophageal reflux.
Physiologic Features of the Canine Esophagus: Effects of Tranquilization on Esophageal Motility
Authors: Gaynor F. , Hoffer R. E. , Nichols Μ. F. , Rosser E. , Moraff H. , Hahn A. W. , MacCoy D. Μ.
Published: February 2025

Esophageal motility was studied in clinically normal dogs. Mean values as to the time and pressure functions of esophageal peristaltic pressure curves are presented. Effects of two dosage levels of tranquilization on the time and pressure functions are reported.
Antigens of Campylobacter fetus subsp fetus Eliciting Vaccinal Immunity in Heifers
Authors: Border Maryon Μ. , Firehammer B. D.
Published: February 2025

These studies were designed to identify the antigens of Campylobacter fetus subsp fetus that elicit vaccinal immunity. Heifers were vaccinated subcutaneously twice (42 days between vaccinations) with bacterins containing K, O, and H antigens (group A), O and H antigens (group B), or O antigen (group C) of the challenge strain. Five heifers were not vaccinated and served as controls (group D).

Two weeks after heifers were given the second vaccination, the immunity of all heifers was challenge exposed by inoculating a live culture against the cervical os. Cervicovaginal mucus samples were examined by microbiological culture technique, using a selective medium, at 7- and 14-day intervals after challenge exposure. One of the six vaccinated heifers in group A became infected, as did all vaccinated heifers in groups B and C and the controls (group D). Only heifers vaccinated with bacterin containing K antigen were resistant to experimental infection with C fetus subsp fetus (P = 0.0002).

Humoral antibody responses to whole-cell antigen were monitored, using a tube agglutination test, with and without treatment of the serum with 2-mercaptoethanol. An anamnestic antibody response of 2-mercaptoethanol-resistant antibody was detected in heifers in both groups A and B. An agglutination test (iggk) was developed to measure immunoglobulin G directed against the K antigen and was used in an attempt to correlate agglutination titers with the immunity to challenge exposure. With the iggk test, the serum agglutination titers of heifers in group A were significantly higher (P < 0.0001) than those of heifers in group B.

The results of these studies indicate that K antigen of C fetus subsp fetus elicits vaccinal immunity and that a direct correlation exists between the iggk test and immunity on a group basis.
Effect of Udder Inflammation on Milk Immunoglobulins and Phagocytosis
Authors: Guidry A. J. , Paape Μ. J. , Pearson R. E.
Published: February 2025

Udder inflammation was induced in two quarters in each of eight cows by infusing oyster glycogen in saline solution. Milk was collected before and after infusion for immunoglobulin (Ig) and phagocytosis assays. Milk Ig and bovine serum albumin were measured by single radial immunodiffusion. The concentrations (mg/ml) of the immunoglobulins (IgA, IgG1, IgG2, and IgM) and bovine serum albumin before and after infusion were: IgA = 0.064 (before), 0.084 (after); IgG1 = 0.323, 0.486; IgG2 = 0.046, 0.094; IgM = 0.091, 0.124; and bovine serum albumin = 0.207, 0.451. The fact that IgA, IgG1, IgG2, and IgM were significantly correlated with bovine serum albumin within the cows before and after inflammation suggests a passive transfer of these Ig during inflammation. Phagocytosis was determined by incubating polymorphonuclear leukocytes collected after infusion with 32P-tagged Staphylococcus aureus in autologous skim milk collected before and after infusion. The difference in percentage of phagocytosis before (42%) and after (36%) infusion was not significant. None of the Ig were significantly correlated with phagocytosis.
Microorganisms Associated with Abscesses of Sheep and Goats in the South of Iran
Authors: Tadayon R. A. , Cheema A. H. , Muhammed S. I.
Published: February 2025

A total of 86 abscesses (45 and 41 abscesses of sheep and goats, respectively) were examined for their causal agents; 44 of these abscesses were located subcutaneously, and the remaining 42 were in lungs, livers, intestines, and udders. A total of 23 different types of microorganisms were isolated from 78 abscesses; bacteria were not detected in the remaining eight abscesses. Microorganisms isolated were: species of the genera Corynebacterium, Staphylococcus, and Streptococcus and Pasteurella, Escherichia coli, and other gram-negative rods. Peptostreptococcus anaerobius and Eubacterium tortuosum were isolated in pure culture from one abscess each in goats. Two to four different microorganisms were associated with 25 of the 86 abscesses. It was determined that 11 isolates of Corynebacterium pyogenes, 2 isolates of Pasteurella haemolytica, 1 of P multocida, and 1 of C pseudotuberculosis were lethal to mice. Two of the C pyogenes isolates from subcutaneous spreading abscesses of goats were pathogenic for rabbits; these two isolates produced similar suppurative inflammation in goats experimentally, but did not cause death. As determined by experimental inoculation, goats were more susceptible than sheep to the two isolates. In nature, subcutaneous abscesses of goats associated with C pyogenes were of a more diffusive type which resulted in generalization of the infection and death of the animals. Postmortem examination of ten goats dying of field infection showed the presence of larvae of the warble-fly Przhevalskiana silenus at the site of infection.
Vascular Anatomy and Surgical Technique for Bilateral Adrenalectomy in the Equid
Authors: Slone D. E. , Vaughan J. T. , Garrett P. D. , Vaden Μ. F. , Purohit R. C.
Published: February 2025

The vascular anatomy of the adrenal glands and a surgical technique for bilateral adrenalectomy in the equid are described. Bilateral adrenalectomy was performed in six ponies and one horse via bilateral transcostal retroperitoneal approaches through the 18th rib during a single anesthetic period. Complications included hemorrhage from the right side only and pneumothorax which usually occurred on the right side. One pony died as a result of the surgical technique. Maintenance of adrenal function was accomplished with desoxycorticosterone pivilate and prednisolone.
Heterotransplantation of Feline Malignant Tumors in Nude Thymusless Mice
Authors: Ladiges W. C. , Van Hoosier G. L.
Published: February 2025

The nude mouse was used to evaluate transplantation of feline tumors and subsequent doxorubicin chemotherapy. Three mammary gland adenocarcinomas and one salivary gland adenocarcinoma were readily transplanted. All were successfully passed at least once. The two sarcomas, a fibrosarcoma and a malignant hemangioendothelioma, failed to grow when transplanted. Growth rates for the adenocarcinomas appeared to be specific for individual tumors. Generally, tumor weights increased five to eight times by days 40 to 50. Structural changes were not observed histopathologically in tumors transplanted several times. When doxorubicin was given intraperitoneally (1 mg/kg of body weight) weekly for 6 weeks to nude mice with transplanted feline mammary gland adenocarcinoma, there was no significant difference (P > 0.05) in weights of tumors of experimental (n = 15) and control (n = 10) mice.
Aqueous Humor Outflow in Beagles with Inherited Glaucoma: Gross and Light Microscopic Observations of the Iridocorneal Angle
Authors: Peiffer Robert L. , Gelatt Kirk N.
Published: February 2025

Gross and light microscopic examinations of the ocular outflow pathways were performed on Beagles with inherited glaucoma subsequent to constant-pressure perfusion of the anterior chamber and observations compared with those of nonperfused and perfused eyeballs (bulbus oculi) from healthy dogs. Iridocorneal angle changes that were noted were interpreted to be secondary, supporting the hypothesis that the disease in the Beagle is an open-angle glaucoma.
Neoplasm of the Mammary Papilla in a Male Dog
Authors: Raflo Charles P. , Diamond Sheldon S.
Published: February 2025

A 7-year-old male Afghan Hound had a mammary neoplasm. The mass was surgically removed and a histologic diagnosis of ductal papillary adenoma of the mammary papilla (nipple) was made. The literature on male canine mammary neoplasia was reviewed and a similar disease in men was compared with the canine lesion.
Trimethoprim and Sulfadiazine: Experimental Infection of Beagles
Authors: Powers T. E. , Powers J. D. , Garg R. C. , Scialli V. T. , Hajian G. H.
Published: February 2025

The purpose in the present study was to determine whether the commercial combination of trimethoprim (tmp) and sulfadiazine (sdz) tribrissen (tri) was more effective than either of the components for treating experimentally induced infection of Streptococcus zooepidemicus. Two dose levels of each were given subcutaneously for treatment, and their effectiveness was compared with that of sulfadimethoxine (sdm) in terms of (i) clinical manifestations, (ii) hematologic changes, (iii) blood culture examinations, and (iv) tissue culture examinations. According to these four measurements, the combination tmp/sdz was more effective than either of the components. This effect was observed at the two dosages of tri (30 and 15 mg/kg). The higher dosage, however, was more effective as demonstrated by three of the measurements. Alone, tmp and sdz were not effective, but sdm treatment was effective in this model.
Effects of Maternal Protein-Energy Malnutrition and Cold Stress on Neutrophil Function of Bovine Neonates
Authors: Woodard L. F. , Eckblad W. P. , Olson D. P. , Bull R. C. , Eversen D. O.
Published: February 2025

The effects of maternal protein or calorie deprivation (or both) on the bactericidal activity of neutrophils and sera from newborn calves subjected to cold stress were studied. Nutritional deficiencies in the dam had little effect on in vitro bactericidal activity of neutrophils and base-line sera taken at birth. Neutrophils obtained at birth destroyed Staphylococcus aureus but not Escherichia coli when incubated with either unheated or heated autologous base-line sera. Heat treatment of base-line sera to inactivate complement did not alter bacterial growth.

When incubated in the presence of autologous base-line sera, neutrophils from 3-day-old calves were no more active in the destruction of either bacterium than were neutrophils from newborn calves. However, addition of day 3 (immunoglobulin-containing) sera enabled day 3 neutrophils to destroy Ε coli (Ρ < 0.0001). The increased destruction of Ε coli by day 3 neutrophils and day 3 sera was not affected by heat treatment of the sera.

Maternal protein deficiency significantly increased (P < 0.05) destruction of Ε coli by day 3 neutrophils and sera. This effect was independent of energy levels. There were no differences observed in the bactericidal activity of neutrophils and sera taken from calves exposed to 1 C or 21 C environmental chambers for 3 days. Also, cold stress-nutritional stress interactions were not detected.
Experimental Transmission of Treponema hyodysenteriae from Mice to Pigs
Authors: Joens L. A.
Published: February 2025

Transmission experiments with Treponema hyodysenteriae were conducted with mice and pigs, using laboratory mice as the carrier host. Mice were intragastrically inoculated with T hyodysenteriae and placed in contact with nonexposed mice or healthy pigs. Contact mice mingled with infected mice at 5 or 180 days after inoculation were shedding T hyodysenteriae in their feces 9 to 14 days after exposure. Pigs exposed directly to infected mouse feces were shedding T hyodysenteriae in their feces after 5 to 7 days of exposure and developed swine dysentery after 11 to 13 days. Transmission of T hyodysenteriae to pigs through direct contact with feces from infected mice indicates that rodents in the field may be a reservoir host and may also be involved in spreading swine dysentery.
Combined Dexamethasone Suppression and Cosyntropin (Synthetic ACTH) Stimulation Test in the Dog: New Approach to Testing of Adrenal Gland Function
Authors: Eiler H. , Oliver J.
Published: February 2025

A combined dexamethasone suppression and cosyntropin (synthetic ACTH) stimulation test was developed in the dog so that information concerning pituitary gland (hypophysis) and adrenal gland competence could be provided in a single trial, during a short time span.

Treatment of dogs with dexamethasone (0.1 mg/kg, im) resulted in total suppression (below assay sensitivity or < 10 ng/ml) of plasma hydrocortisone (cortisol) at postinjection hour (pih) 2 in 100% of the dogs, whereas suppression was inconsistent at pih 1. Cosyntropin (0.5 U/kg, iv) administration to normal or dexamethasone-suppressed dogs increased plasma hydrocortisone concentration 3.5 to 4.5 times base-line values at pih 1, which was the time of maximal effect.

The combined test concept for adrenal gland function is valid, convenient (three sample collections; 3-hour period), and allows testing of adrenal gland response to dexamethasone suppression and ACTH stimulation in a single trial. The following test procedure for dogs is recommended: (i) collect base-line plasma sample (0900 hours) followed by injection of dexamethasone (0.1 mg/kg, im); (ii) collect second plasma sample 2 hours after dexamethasone (to evaluate suppression of plasma hydrocortisone concentration) followed by the injection of cosyntropin (0.5 U/kg, iv); and (iii) collect a third plasma sample 1 hour later to evaluate plasma hydrocortisone concentration after cosyntropin stimulation.
Effect of Age on Tolerance of Calves to Chlorpyrifos
Authors: Palmer J. S. , Rowe L. D. , Crookshank H. R.
Published: February 2025

Groups of five calves (1 to 2 weeks old) or older calves (4 to 6 months old) were treated topically with increasing concentrations of chlorpyrifos [O,O-diethyl-O(-3,5,6-trichloro-2-pyridinyl) phosphorothioate] to determine their susceptibility to chlorpyrifos toxicity. Newborn calves also were given oral doses of technical grade (97.4%) chlorpyrifos to estimate their susceptibility by this treatment route. Topical applications to newborn calves consisted of 0.02%, 0.06%, or 0.12% chlorpyrifos administered as a spray to the entire body surface. Oral dosages given the newborn calves consisted of 5, 10, or 25 mg of chlorpyrifos/kg of body weight. Topical applications were administered to the older calves in the same manner as were applications to the newborn calves, but at concentrations of 0.25%, 0.5%, 0.9%, or 2.3%. Minimum dosages producing signs of toxicosis in newborn calves which were orally and topically given chlorpyrifos were 25 mg/kg of body weight and 0.06%, respectively. All five newborn calves sprayed with 0.12% chlorpyrifos were severely poisoned and were treated with atropine. One of these calves died within 48 hours after exposure to chlorpyrifos despite antidotal therapy.

Signs of poisoning were not observed in older calves sprayed with 0.25%, 0.5%, or 0.9% chlorpyrifos. One Brahman-cross calf sprayed with 2.3% chlorpyrifos developed signs of mild poisoning that dissipated in 72 hours without treatment. Four older non-Brahman calves sprayed with 2.3% chlorpyrifos did not show signs of poisoning. Seemingly, 4- to 6-month old calves have an increased tolerance to topically applied chlorpyrifos compared with the tolerance of newborn calves, and the magnitude of this increased tolerance is 30-fold or higher.
Crystalline Inclusions in Erythrocytes Parasitized with Babesia equi Following Treatment of Ponies with Imidocarb
Authors: Simpson Charles F. , Taylor W. J. , Kitchen H.
Published: February 2025

Four splenectomized Welsh ponies were infected with Babesia equi. Two ponies were treated with imidocarb dipropionate, and two were not treated. By light microscopic examination, 1% to 2% of the parasitized erythrocytes of treated ponies contained crystalline inclusions. The crystals were rectangular, diamond, or burr shaped. They occupied most of the erythrocytic cytoplasm, and, as a result, the remainder of the pale staining cytoplasm was inconspicuous in Wright-Giemsa-stained blood smears. The size and shape of intraerythrocytic inclusions varied when examined by electron microscopy, but in most instances they were either adhered to or were located close to the parasite. The sides of crystals were either smooth or serrated, and corners were either sharp or notched. Fractures or faults were common in large crystals. Parasitized erythrocytes of non-treated ponies and nonparasitized erythrocytes of treated ponies did not contain crystals.

Four hemoglobulin types were identified in five noninfected, non-treated Welsh ponies from the same herd.
Intramammary Coliform Infection After Heavy External Contamination of Teats
Authors: Schultze W. Donald , Thompson Paul D.
Published: February 2025

Teats of lactating dairy cows were exposed to massive, repeated external contamination by application of a freshly prepared broth culture of Escherichia coli that was maintained in wet contact with the teat ends during 14 or 21 successive entire intermilking periods. When contamination was restricted to the intermilking periods by dipping teats in an iodophor germicide before each milking, 18 new intramammary infections occurred among the 93 mammary quarters at risk. The rate of infection achieved was 1/89 milkings. Transient residence of E coli in streak canals and frequent occurrence of sterile inflammation of mammary quarters made diagnosis of new infection difficult.

Teats also were exposed to E coli without sanitization before milking. The milking machine was modified to maximize the likelihood of contaminated milk droplets impacting on teat orifices through back-jetting. Diagonally opposed milking machine inflations were fitted with rifled-bore short milk tubes designed to be protective against back-jetting. The rate of new E coli infections was 1/291 milkings among control and protected quarters. When contamination was extended into the milking operation, the new infection rate was not greater than was that achieved when exposure was limited to intermilking periods; therefore, the protective value of rifled-bore short milk tubes was not adequately tested and a role of the machine as a vector was not demonstrated.
Wavelength of Ultraviolet Radiation that Enhances Onset of Clinical Infectious Bovine Keratoconjunctivitis
Authors: Kopecky K. E. , Pugh G. W. , Hughes D. E.
Published: February 2025

Cellulose acetate filtered ultraviolet (uv) radiation and unfiltered uv radiation were used on calves that were subsequently challenge exposed with Moraxella bovis. The onset, course, and severity of infectious bovine keratoconjunctivitis (ibk) were studied. Ten calves irradiated with unfiltered uv had the disease 1 to 2 days after Μ bovis challenge exposure; all 10 calves had moderate to severe ibk. Ten calves irradiated with filtered uv and 10 calves not irradiated manifested ibk in a similar manner. The date of onset and the severity of the disease varied.

Evidence is presented to support the contention that the wavelengths (around 270 nm) which are eliminated by cellulose acetate enhance the course of ibk. The effects on ibk of environmentally increased solar uv radiation is also discussed.
Immunoglobulin A Response of the Bovine Fetus and Neonate to Escherichia coli
Authors: Yamini Behzad , Sleight Stuart D.
Published: February 2025

The chronologic appearance of immunoglobulin (Ig) A-containing plasma cells and their distribution and numbers in the intestinal tract, spleen, and mesenteric lymph nodes were determined in beef calves inoculated in utero with Escherichia coli O26-K60:NM bacterin or with saline solution. Secondary responses were assessed by oral revaccination or by challenge exposure to live E coli. Specific immunofluorescent procedures were used to count IgA-containing plasma cells.

Appreciable numbers of IgA-containing plasma cells were seen in in utero-vaccinated calves at birth. Oral vaccination or challenge exposure with E coli increased the number of plasma cells. The caudal part of the jejunum and the ileum and related lymph nodes had more IgA-containing cells than any of the other tissues examined. In revaccinated and challenge exposed calves, the spleen was especially active in the formation of IgA-containing plasma cells. The results indicate that the entire small intestine, the draining lymph nodes, and the spleen were involved in IgA formation in these young calves. Age as a factor in IgA production was seen in the control calves which had no indication of IgA-containing cells before 9 days of age. None of the in utero-vaccinated calves at birth or at necropsy had evidence of IgA in serum.
Evaluation of Granulated Fenbendazole (22.2%) Against Induced and Naturally Occurring Helminth Infections in Cats
Authors: Roberson Edward L. , Burke T. Michael
Published: February 2025

A granulated formulation of 22.2% fenbendazole was tested for anthelmintic activity against helminths in cats. The drug was administered in 20 g of canned food on each of 3 days at a dosage of 50 mg/kg of body weight/day. Of 31 young adult cats harboring naturally occurring infections of Toxocara cati, 16 were treated and 15 served as controls. There was 100% clearance of ascarids from all treated cats. Among controls, 18% of the ascarid burden was expelled naturally.

Thirty additional cats were acclimated for 2 months prior to infecting them experimentally with Aelurostrongylus abstrusus, Taenia taeniaeformis, and Ancylostoma tubaeforme. Treatment caused a transitory reduction in the number of lungworm larvae. Histopathologically, cells of developing eggs and of a majority of 1st-stage larvae in lungs of treated cats had evidence of marked degeneration and necrosis, whereas the same stage of larvae in lungs of control cats were normal. Although the number of lung lesions in treated cats was approximately half the number found in controls, there was no significant (P > 0.05) indication that this was due to treatment.

Fenbendazole was effective against induced infections of A tubaeforme and Taen taeniaeformis. Greater than 99.9% of hookworms were expelled from 16 treated cats as compared with a 2% natural expulsion from 15 controls. Of 24 cats that developed patent infections of Taen taeniaeformis, 12 were treated and cleared of this parasite, whereas 9 of 12 controls continued to harbor 1 to 10 tapeworms at the time of necropsy.

Fenbendazole at a dosage of 50 mg/kg/day × 3 days appeared to be an effective anthelmintic against the common ascarid, hookworm, and tapeworm of cats. Its activity against lungworms was inconclusive at the dosage used, but the data suggest the need for investigating its activity against this parasite at higher dosages, for longer periods of treatment, or both.
Adrenal Gland Function in Dogs Given Methylprednisolone
Authors: Spencer Karen B. , Thompson F. N. , Clekis T. , Lorenz Μ. D.
Published: February 2025

Serum cortisol (hydrocortisone) was measured by radioimmunoassay in dogs given methylprednisolone (mp) orally or methylprednisolone acetate (mpa) im. The mp was given on a daily and on an alternate-day basis to different treatment groups and the mpa was administered weekly. Samples of blood were obtained twice a week over a 9-week treatment period for serum cortisol determination, and the adrenal gland response to ACTH was assessed on posttreatment days 1, 3, 5, and 7. Administration of mp on an alternate or daily basis caused a slight but significant (P < 0.05) depression in mean resting cortisol values over time. The mpa administration caused a severe depression of resting serum cortisol values. In response to ACTH, cortisol values invariably increased sharply in nontreated control dogs and in those dogs given mp on an alternate-day basis. Dogs given mp daily had a depressed response to ACTH. The mpa treatment resulted in adrenal cortices that were unresponsive to ACTH. Dogs given mpa, but not challenge exposed with ACTH, had markedly lowered cortisol values for at least 2 weeks after cessation of treatment. Consequently, a difference between daily- and alternate-day mp administration was detected after ACTH challenge exposure; mpa administration inhibited adrenal cortisol secretion for at least the duration of the experiment.
Pathogenicity of Toxoplasma gondii Oocysts to Ponies
Authors: Al-Khalidi N. W. , Weisbrode S. E. , Dubey J. P.
Published: February 2025

Nine ponies were fed 100,000 infective Toxoplasma gondii oocysts and were given corticosteroid injections before and after feeding the T gondii oocysts. Titers to the Sabin-Feldman dye tests (1:2 to 1:16,384) developed within postinoculation days (pid) 7 to 21 and antibodies persisted to pid 133. Toxoplasma organisms were isolated from the tissues of 4 ponies (heart of 4, brain of 2, spinal cord of 3, diaphragm of 1, skeletal muscle of 1, liver of 1, kidneys of 1) killed between pid 36 and 63, but not from 5 ponies killed between pid 117 and 150. Seemingly, ponies are one of the more resistant species of animals to develop clinical toxoplasmosis.
Evaluation of a Formalin-Inactivated Rift Valley Fever Vaccine in Sheep
Authors: Harrington D. G. , Lupton H. W. , Crabbs C. L. , Peters C. J. , Reynolds J. A. , Slone T. W.
Published: February 2025

A formalin-inactivated Rift Valley fever (rvf) vaccine prepared in cell culture for human use was immunogenic in sheep. Vaccine was administered as a single dose of diluted (1:5) or undiluted vaccine with or without an adjuvant. Serum-neutralizing antibodies induced by rvf vaccine persisted for at least 7 months. Seven of 11 vaccinated sheep with prechallenge plaque-reduction neutralization (prn80) antibody titers of ≤ 10 were protected against challenge exposure with 106 plaque-forming units of Zagazig 501 strain of rvf virus. Challenge exposure induced abortion in 2 of 2 pregnant sheep. Five sheep with prn80 titers ≥ 1:20 were protected from detectable viremia after challenge exposure. Additionally, 5 of 6 lambs (3 months old) were protected (by maternal antibodies) against challenge exposure. Challenge control sheep developed clinical disease and detectable viremia after exposure. Virus was isolated from saliva of 1 challenge control sheep and virus was transmitted by contact exposure to 1 of 4 seronegative contact-control sheep.

Immunization of sheep with formalin-inactivated rvf vaccine induced a priming effect against rvf viral antigens. Challenge exposure with rvf virus resulted in significantly higher neutralizing titers in vaccinated sheep than in nonvaccinated sheep.
Experimental Infection of Cattle with Yersinia enterocolitica Serotype O9: Serologic Responses
Authors: Mittal K. R. , Barnum D. A. , Tizard I. R.
Published: February 2025

Cattle were exposed to Yersinia enterocolitica O9 by the oral or intramammary routes. Oral exposure failed to generate significant serologic responses. In contrast, intramammary inoculation produced a marked response, the serum antibodies provoked in this manner reacting strongly with Brucella abortus. The serum agglutination, indirect hemagglutination, microplate agglutination, and quantitative plate agglutination techniques were used to characterize the serologic responses to the 2 organisms. None was an entirely satisfactory technique for obtaining diagnostic discrimination between brucellosis and yersiniosis.
Vascular Supply of the Equine Stifle Joint
Authors: Updike Susan J. , Diesem Charles D.
Published: February 2025

The vascular supply of the equine stifle joint was investigated, using latex vascular injections of pelvic limbs from 3 adult horses and 6 ponies. Vessels were grossly dissected to the small arteriole level. The primary source of blood supply was the femoral artery and its branches which entered the joint on the caudal and medial surfaces. The superficial vasculature arose from the caudal branch of the deep circumflex iliac artery cranially and laterally, and from the saphenous and descending genicular arteries medially. The deep vasculature arose from the popliteal artery and its branches on the caudal joint surface. These 2 layers of vessels arborized to form the vascular rete which surrounded the joint and gave off branches to supply the articular capsule and the intraarticular structures. Venous drainage paralleled arterial pathways.
Efficacy of Immunoserodiagnostic Procedures in the Recognition of Canine Immunologic Diseases
Authors: Quimby Fred W. , Smith Christina , Brushwein Mary , Lewis Robert W.
Published: February 2025

Six immunologic tests were conducted on a large population of dogs with a variety of diseases. The test results were analyzed retrospectively and correlated to the clinical and final pathologic diagnoses. The results indicated that rheumatoid factor and the direct antiglobulin (Coombs) test were both sensitive and specific for the diagnoses of canine rheumatoid arthritis and autoimmune hemolytic anemia. The antinuclear antibody test was useful in supporting the diagnosis of systemic lupus erythematosus (sle) only when both antibody titer and the staining pattern were taken into consideration. The lupus erythematosus cell test was specific but not sensitive when used to confirm a diagnosis of canine sle.

Cellulose acetate serum electrophoresis and immunoelectrophoretic techniques were each useful in supporting the diagnosis of multiple myeloma.

Epizootiologic data collected in this study indicated that dogs with primary immunologic disease had a poor prognosis. A female predisposition was observed in cases of canine autoimmune hemolytic anemia and sle. Ovariectomy seemed to prevent the development of canine sle.
Effect of Inspired-Air Warming and Humidification in the Prevention of Hypothermia During General Anesthesia in Cats
Authors: Haskins Steve C. , Patz J. D.
Published: February 2025

An inspired-air heating and humidifying device was constructed and evaluated with regard to its ability to maintain mean body heat in anesthetized cats. Control cats exhibited a net heat loss of −5.960 and −2.970 Kcal for each of 2 successive hours. The respiratory heat loss was only 0.675 Kcal per hour. Subjects inhaling warmed and humidified oxygen exhibited a net heat loss of −2.860, −1.900, and −0.742, for each of 3 successive hours, whereas respiratory heat gain was 0.643, 0.742, and 0.776 Kcal for the same periods. The inspired-air heating and humidifying technique was associated with a significantly slower decrease in body temperature (P < 0.05) after 45 minutes. The inspired-air heating technique is beneficial in minimizing body heat loss during general anesthesia in cats, but is not effective enough to supplant other methods.
Changes in Periparturient Fecal Egg Counts in Beef Cows Calving in the Spring
Authors: Hammerberg Bruce , Lamm W. Dennis
Published: February 2025

A herd of mature Angus and Angus-Holstein-Friesian cows calving between March and May was maintained at 80% and 100% of National Research Council's recommended total digestible nutrient (tdn) levels during the winter. Changes in fecal nematode egg counts of these cows, expressed as eggs/5 g of feces and quantitated by the Wisconsin sugar flotation technique, were detected perinatally and were correlated with breed, nutritional level, and time of year. A limited, yet highly significant (P < 0.001) increase in egg output was found in cows at calving. Anthelmintic treatment at calving caused postcalving egg counts that were statistically lower than were those from nontreated cows. When breed and nutritional level were considered independently, there was less influence on egg counts than when the interaction of breed and nutritional level was examined. Angus-Holstein-Friesian cows fed 80% tdn requirements had the greatest perinatal increase in egg output, and those fed 100% tdn had the smallest increase of all groups. Angus cows responded in an opposite manner to the nutritional level and had increases in egg counts intermediate to those counts of Angus-Holstein-Friesian cows. This characterization of the periparturient egg output by mature cows aided in evaluating the role of grazing cows in contaminating pastures.
Rotavirus Infection in Foals
Authors: Conner Μ. E. , Darlington R. W.
Published: February 2025

Fecal samples from 86 foals with diarrhea were examined by electron microscopy during a 2.5 year period. Of these, 26 (30%) were positive for rotavirus. All of the cases were found in epizootic areas. The disease was produced in an experimental foal by inoculation via stomach tube of a bacteria-free fecal filtrate containing rotavirus. Examination of postmortem tissues from the duodenum and jejunum of 2 naturally infected foals and an experimentally infected foal revealed replicating virus in the intestinal epithelial cells. A limited survey of complement-fixing antibody to rotavirus in horses from Kentucky, Virginia, and France indicated that all horses had antibody to the virus. The sole exception was 1 foal from which blood samples were collected prior to suckling. These results were presumptive evidence that rotavirus is a major cause of diarrhea in foals, and the presence of antibody in horses from diverse areas is evidence for the ubiquitousness of this infection.
Pseudomonas Pneumonia of Mink: Pathogenesis, Vaccination, and Serologic Studies
Authors: Long Gerald G. , Gallina Anthony Μ. , Gorham John R.
Published: February 2025

Fulminating pneumonia was produced in mink by the intratracheal administration of Pseudomonas aeruginosa. The sequence of pulmonary lesions was focal inflammation, focal necrosis, and widespread inflammation and necrosis. Secondary lesions of peracute hemorrhage and necrosis were the result of bacterial spread via the airways. Invasion of vessel walls by P aeruginosa was a terminal event and was secondary to bacillary invasion and necrosis of adjacent tissues. Regional (lymphatic) and systemic spread of bacteria followed the development of pulmonary lesions, but there was little morphologic evidence of tissue damage in other organs. Immunofluorescence studies showed that P aeruginosa antigen was dispersed within pulmonary cells and was free in the lung parenchyma. Mink surviving beyond postinfection hour 60 had a macrophage infiltration into limited pulmonary lesions.

A vaccine trial was conducted with P aeruginosa lipopolysaccharides (lps) used as antigen, and an enzyme-linked immunosorbent assay was used to detect antibody. Antibody was detected in mink after vaccination with lps or natural exposure. Mink with antibody to lps, from vaccination or naturally acquired, were resistant to experimental infection.
Hemorrhagic Syndrome Induced in Chicken Embryos by Intravenous Inoculation of Ground Chicken Embryo Extract
Authors: Tyler D. E. , Sawyer Μ. Μ. , Osburn B. I. , Benken B.
Published: February 2025

SUMMARY AND CONCLUSIONS

The hemorrhagic syndrome which occurred after the iv inoculation of ground embryo extract into living chicken embryos resulted from rapid activation and depletion of the clotting mechanism. The syndrome was prevented by the addition of heparin to the ground embryo inoculum. The characteristics of the hemorrhagic syndrome suggest that the phenomenon is the result of disseminated intravascular coagulation.
Efficacy of Ivermectin (22,23-Dihydroavermectin B1) Against Gastrointestinal Parasites in Ponies
Authors: Klei Thomas R. , Torbert Betty J.
Published: February 2025

The controlled test method was used to evaluate the antiparasitic efficacy of im inoculated 22,23-dihydroavermectin B1 (ivermectin) against gastrointestinal parasites of horses (ponies). Parasite infections were naturally acquired in southern Louisiana. Dose levels of the drug tested were 0.2 mg/kg, 0.3 mg/kg, and 0.5 mg/kg.

Ivermectin at all dose levels tested had an efficacy greater than 97% (P < 0.05) against Gasterophilus intestinalis larvae, Trichostrongylus axei, Oxyuris equi larvae, Strongylus vulgaris, S edentatus, 15 species of small strongyles, and small strongyle larvae. Ponies were less uniformly infected with Habronema sp larvae, G nasalis larvae, Parascaris equorum, O equi adults, Anoplocephala perfoliata, S equinus, and 11 small strongyle species, and statistical analysis was not possible to do. However, observations indicate that the drug was also highly effective against these species. There were no gross or clinical reactions observed in treated animals. Dissections of the injection sites revealed spindle-shaped lesions, 3 to 5 cm long, in a few ponies in all treatment groups, including those given the placebo injection.
Effects of Clonidine on Glucose Production and Insulin Secretion of Cattle
Authors: Gorewit R. C.
Published: February 2025

Clonidine2-(2,6-dichlorophenylamine)-2-imidazoline hydrochloride, a potent α-adrenoceptor stimulant, was given to dairy heifers. Administration of either 2 or 20 μg of drug/ kg during 10 minutes resulted in decreased immunoreactive serum insulin (iri) concentrations and increased serum glucose concentrations 5 minutes after administration. Drug administration resulted in a protracted decrease (P < 0.01) of serum iri and a protracted increase (P < 0.01) in serum glucose. Doses differed significantly (P < 0.01) with regard to their ability to alter iri and glucose concentrations. Clonidine also significantly (P < 0.05) enhanced glucose release from liver slices of heifers in vitro. Clonidine stimulated cyclic 3'5' adenosine monophosphate (cAMP) production in liver tissue slices when they were incubated in the presence (or absence) of theophylline, indicating that the mechanisms bringing about changes in liver glucose release and cAMP production were related.
Response of Calves to Lung Challenge Exposure with Pasteurella haemolytica After Parenteral or Pulmonary Immunization
Authors: Wilkie B. N. , Markham R. J. F. , Shewen P. E.
Published: February 2025

In 3 experiments, calves were vaccinated by intrabronchial or subcutaneous injection of formalinized Pasteurella haemolytica. Immunization was evaluated by assessing the clinical and pathologic responses to pulmonary challenge exposure with live homologous bacteria. Serum and bronchoalveolar washings were titrated for antibody by indirect (antiglobulin) bacterial agglutination.

Response to challenge exposure was determined by increased rectal temperature and faster respiratory rate. In all experiments, the most obvious clinical change occurred in challenge-exposed calves which had been vaccinated by the subcutaneous injection of killed P haemolytica with added adjuvant. Also, macroscopic pulmonic lesions were recorded most frequently in calves vaccinated by this route. In all instances, immunization resulted in elevated anti-Phaemolytica titers both in lung and serum.
Canine Population Dynamics; A Study of the Manhattan, Kansas, Canine Population
Authors: Nassar R. , Mosier J. E.
Published: February 2025

Analysis of the age distribution in the pet population of dogs in the community of Manhattan, Kansas from 1968 to 1979 revealed that the distribution was stationary and the rate of population change (λ1) was close to 1, which means, that if present conditions do not change, the population probably would remain stable in size in the future.

The number of females spayed in the Manhattan population reached a frequency of 66% in 1979. Considering only present age-dependent birth and survival rates, the population could not maintain itself and would decrease rapidly in size. It was found, however, that the population is maintained by a high net rate of immigration, with about 57% of all dogs under 6 months old coming from outside the Manhattan population.

The ratio of people to dogs in Manhattan was estimated to be 4.14:1; about 41% of all dogs under 6 months of age were acquired through breeders.

Roaming animals in 1 year represented about 12% of the canine population in Manhattan; of those, 36% were stray (not claimed by owner) and the rest were owned and redeemed. The data represented only a portion of the population (dogs with responsible owners) and for a complete understanding of the dynamics of the entire population, one should analyze roaming dogs in a similar way.

The methods described in this study should be useful for collecting data to be used by veterinarians and municipal authorities confronted with proposals for regulation dealing with reproduction and pet population.
Aqueous Humor Outflow in Beagles with Inherited Glaucoma: Constant Pressure Perfusion
Authors: Peiffer Roger L. , Gum Glenwood G. , Grimson Roger C. , Gelatt Kirk N.
Published: February 2025

Determination of facility of aqueous humor outflow (C), using constant pressure perfusion, was performed in vivo in normal dogs and in Beagles with inherited glaucoma at different stages of the disease process. Measurements were taken at 10 mm of Hg increments of intraocular pressure (iop) from 10 to 50 mm of Hg iop in the controls and to higher levels of iop, as needed, to obtain 3 consecutive intervals in which perfusion was required in glaucomatous animals. In normal dogs, C increased slightly as iop increased to a maximum of 0.22 at 50 mm of Hg. In glaucomatous dogs, C was significantly (P = 0.001) reduced compared with the value in the controls, with a maximum value of 0.09 at 50 mm of Hg.