bluuebunny/crossref_metadata_2025 huggingface dataset:
Bovine Viral Diarrhea Infection in Pregnant Swine
Authors: Stewart W. C. , Miller L. D. , Kresse J. I. , Snyder Μ. L.
Published: February 2025

Twenty pregnant gilts (5 groups of 4) were infected experimentally with 1 of 4 strains of bovine viral diarrhea virus (bvdv) administered intranasally-orally. Blood specimens were taken from the gilts on postinfection day (pid) 7 and cultured for virus. Serum specimens, obtained on pid 21 and at termination of the experiment, were tested for neutralizing antibodies. At 90 to 112 days of gestation, the gilts were euthanatized and their fetuses were examined for evidence of intrauterine infection.

Evidence of infection was demonstrated in all of the gilts, either by isolation of bvdv at pid 7 or subsequently by detection of neutralizing antibody titers. Intrauterine infection was confirmed in one of 20 gilts by isolation of bvdv, detection of neutralizing antibodies, and demonstration of microscopic lesions in the fetuses. The microscopic lesions were characterized as nonsuppurative meningitis and choroiditis. Clinical signs of disease were not seen in the infected fetuses.

Of 8 gilts exposed to strains of bvdv pathogenic for cattle, 1 gilt developed intrauterine infection, 2 gilts were found barren, and 3 gilts had significantly fewer fetuses than corpora lutea.
Experimental Infection of Pregnant Sows with Porcine Enteroviruses
Authors: Huang J. , Gentry R. F. , Zarkower A.
Published: February 2025

In a series of experiments, SMEDI A—porcine enterovirus serotype 8—was given by intrauterine route to pregnant gilts at intervals between gestation days 0 and 30, and SMEDI C—porcine enterovirus serotype 1—was given to pregnant gilts at intervals between gestation days 30 and 41 to 43. Antibodies were detected in fetuses from groups inoculated at gestation days 30 and 41 to 43, whereas virus was isolated from fetuses only from groups inoculated at gestation days 41 to 43. When inoculated directly into the uterus, embryonic or fetal infection with these viruses was observed regardless of the preinoculation serologic status of the gilts, indicating that maternal antibody had no effect on embryonic or fetal infections after the virus was in the uterus.

Intranasal inoculation of SMEDI C caused embryonic or fetal infections in seronegative gilts but not in gilts that carried specific antibody to SMEDI C at the time of exposure. Antibodies in gilts that were seropositive at time of inoculation probably neutralized the virus before it could reach the uterus and thus prevented embryo or fetal infections.
Responses of Goat Ruminal Musculature to Bradykinin and Serotonin In Vitro and In Vivo
Authors: Veenendaal G. H. , Woutersen-van Nijnanten F. M. A. , van Miert A. S. J. P. A. M.
Published: February 2025

Concentration-response curves obtained for contraction of goat rumen strips indicated that both bradykinin (bk) and serotonin (5-hydroxytryptamine creatinin sulphate; 5-ht) are potent agents. Sodium meclofenamate antagonized the smooth muscle-stimulating action of bk; the 5-ht blocking agents xylamidine and methysergide diminished the contractile effects of 5-ht. The results indicated that the antagonisms are noncompetitive in nature. In vivo, both bk and 5-ht caused a dose-dependent inhibition of the rumen contraction sequences. The bk was the more potent of the two compounds. This inhibition was probably due to an increase in ruminal smooth muscle tone, resulting in reflex inhibition of the normal cyclical contraction sequences. In conscious goats, bk induced tachycardia, whereas 5-ht produced only minor changes in heart rate. Treatment with sodium meclofenamate or phenylbutazone prevented the bk-induced inhibition of rumen motility. Treatment with the 5-ht blocking agents only partly reduced the 5-ht-induced effects.
Chemoimmunotherapy for Canine Lymphosarcoma; A Prospective Evaluation of Specific and Nonspecific Immunomodulation
Authors: Weller R. E. , Theilen G. H. , Madewell B. R. , Crow S. E. , Benjamini E. , Villalobos A.
Published: February 2025

Fifty-six dogs were given chemoimmunotherapy for spontaneous lymphosarcoma. The dogs had been given identical combination chemotherapy (8 weeks) for induction of remission, and after achieving complete clinical remission, they were randomly assigned to one of three treatment groups to evaluate immunotherapy as a method ancillary to chemotherapy to maintain or extend the remission. For immunostimulation, one-third of the dogs were given chemically modified autochthonous tumor cell extract in Freund's complete adjuvant (fca). one-third were given nonmodified tumor cell extract in fca, and one-third were given fca alone. A historical control population of dogs given the same chemotherapy was used for comparison.

Of the 56 dogs, 50 (89.3%) achieved initial remission, but 18 of the latter relapsed clinically during the initial 8-week-chemotherapy regimen. The remaining 32 dogs (or 57.1% of the original 56 dogs) were subsequently given immunotherapy. Duration of remission and survival time were recorded. The median remission duration and survival time for all dogs given immunotherapy following cytoreductive chemotherapy were significantly longer than the historical control population given chemotherapy alone. However, there was no significant difference in remission duration or survival among the three immunotherapy groups.
Feline Chronic Progressive Polyarthritis
Authors: Pedersen Niels C. , Pool Roy R. , O'Brien Timothy
Published: February 2025

Twenty cats with a chronic progressive polyarthritis were studied. The disorder occurred exclusively in male cats, and all but six of the cats were between 1.5 and 5.0 years of age, There were two forms of the disease as determined by radiographic changes: joint instability and deformity, and clinical course. The most prevalent form of the disease was characterized by osteopenia and periosteal new bone formation surrounding affected joints. Marginal periarticular erosions and collapse of the joint spaces with fibrous ankylosis occurred with time, but joint instability and deformities were not seen. The second form of the disease was characterized by severe subchondral marginal erosions, joint instability, and deformities. The periosteal proliferative form resembled Reiter's arthritis of man, and the deforming type resembled human rheumatoid arthritis. The disease began as tenosynovitis and synovitis, with subsequent changes in the articular cartilage and periosteal bone. Histopathologic changes in these cats were similar to those occurring in both chronic Reiter's and rheumatoid arthritis of man.

Chronic progressive polyarthritis of cats was not caused by identifiable bacteria or mycoplasma, but was etiologically linked to feline leukemia virus (FeLV) and feline syncytia-forming virus (FeSFV) infections. The FeSFV was isolated from the blood or was detected by a serologic test in all of the cats with the disease, whereas FeLV was isolated or identified by immunofluorescence technique in 60% of the cats. The arthritis could not be reproduced by inoculation of cell-free synovial tissue from diseased cats or with tissue culture fluid containing FeSFV and FeLV isolates. It was postulated that arthritis was an uncommon manifestation of FeSFV infection that occurred in predisposed male cats. Feline leukemia virus may not have been directly involved in the disease, but may have acted in some way to potentiate the pathogenic effects of FeSFV.
Immunologic Effects of Experimental Iodine Toxicosis in Young Cattle
Authors: Haggard Dale L. , Stowe Howard D. , Conner Gabel H. , Johnson Donald W.
Published: February 2025

A study was designed to evaluate effects of 4 dosage levels (0, 50, 250, or 1,250 mg) of daily iodine supplementation on cell-mediated and humoral immune mechanisms in 40 calves, 10 per group, for a 6-month period. Immune and inflammatory responses were measured by titers to brucella, leptospira, and infectious bovine rhinotracheitis virus vaccinations, by stimulation of lymphoctye mitoses with pokeweed, phytohemagglutinin (pha), and conconavalin A mitogens, by intradermal pha responses, by in vitro phagocytosis of Candida albicans by wbc, and by total wbc counts. Calves given 1,250 mg of iodine daily had significant (P = < 0.05) decreases in persistence of antibody titers to brucella and leptospira organisms, in lymphocyte mitotic activity, in pha injection induration, in phagocytosis by wbc, and in wbc counts. Calves fed iodine at 50 or 250 mg daily tended to have decreased leptospiral titers, lymphocyte mitoses, pha injection induration, and in vitro phagocytosis by wbc compared with responses of controls. Seemingly, large amounts of dietary iodine interfere with titer maintenance to some antigens, with lymphocyte DNA synthesis, and with phagocytic activity of wbc.
Role of the Raccoon in the Transmission of Pseudorabies: A Field and Laboratory Investigation
Authors: Wright James C. , Thawley David G.
Published: February 2025

Serum samples were collected from 42 raccoons trapped in a pseudorabies enzootic area of Missouri. All samples were negative for neutralizing antibodies to pseudorabies virus (prv).

Raccoons were orally exposed with one of four dose levels of prv. The raccoons were found to be susceptible to moderately large doses of prv tissue culture infective dose (104 – 105 tcid50). All raccoons given 103 tcid50 of prv survived and did not develop clinical signs. The prv was consistently isolated from tonsillar swabs collected from raccoons that died after exposure. The prv was also isolated from the brain, tonsils, lungs, and salivary glands of raccoons that died. It was isolated from samples of the brain and tonsils collected from a raccoon 5 days after death.

Neutralizing antibodies to prv could not be detected in the serum of raccoons that survived prv exposure. Tonsillar swabs and tissue samples collected from these raccoons were free of prv. The results indicated that the raccoon may serve as a short-term reservoir for prv, but it is unlikely to have an epizootiologic role as a long-term, subclinical carrier of the virus.
Clearance of Technetium 99m-Labeled Sulfur Colloid Particles from the Blood in Normal Dogs and in Dogs with Hepatic Granulomata
Authors: Gorman N. T. , McCarthy T. , Owen L. N.
Published: February 2025

The clearance of technetium 99m-labeled sulfur colloid particles from the blood was studied in a series of seven clinically normal dogs. The effect of recent (6 hours) injections of bacteria bacillus Calmette-Guerin or Corynebacterium parvum markedly impeded the clearance of the colloid from the blood, due to a partial blockade effect. This phenomenon was reversible. When multiple experimentally induced hepatic granulomatous lesions were present, the clearance was similarly impeded. In contrast, however, this was not a reversible event. The possible application of this technique to diagnosis was discussed.
Economic Value and Course of Infection After Treatment of Cattle Having a Low Level of Nematode Parasitism
Authors: Leland S. E. , Davis G. V. , Caley H. K. , Arnett D. W. , Ridley R. K.
Published: February 2025

To determine whether it is economically advantageous to treat calves having inapparent parasitism, we conducted experiments from 1971 to 1976, involving more than 1,800 calves from 30 pens or lots, using formulations of thiabendazole, levamisole, and crufomate (ruelene). Differential egg counts, cultured larvae, and cultured parasitic stages were used to estimate the kind and degree of nematode parasitism. Differentiation of infective larvae consistently established Cooperia as the predominating (%) genus in all fecal samplings. Bunostomum, when initially present, decreased or disappeared, whereas Trichostrongylus increased; other genera fluctuated less consistently. These qualitative generic fluctuations were not primarily the result of treatment, but more likely were seasonal variation.

Judged by average daily gain (adg), anthelmintic treatment was statistically advantageous at one or more points during the observation periods in 10 of 13 treated groups. In seven treated groups, the observation periods were concluded with statistical advantage in adg, whereas in three groups, compensatory gain by corresponding controls had neutralized earlier advantages. The comparative influence of the various anthelmintics was not consistent from year to year.

When total cost/kilogram gain was calculated from feed efficiency measurements and other costs, economic treatment advantage was evident in seven of 11 tests (7 of 10 treatment groups) from 1973 through 1976. This financial advantage, due primarily to feed efficiency and noted after 28 to 51 days, justified anthelmintic treatment. This advantage was not likely lost by the animals in subsequent periods (to 218 days) on pasture or in lots, since adg indicated the treated calves performed either as well as, or better than, the nontreated controls. Considering all aspects of the study, the results indicate calves coming into Kansas from southern states and weighing 184 to 267 kg may possess a level of subclinical (symptomless) nematode parasitism that when treated will result in a response justifying expense for using anthelmintics.
Metabolic and Cellular Profile Testing in Calves Under Feedlot Conditions, Using Discriminant Analysis to Identify Calves with Low Potential for Weight Gain
Authors: Farver T. B. , Veshkini F. , Ruppanner R. , Norman B. B.
Published: February 2025

Thirty-eight variables were measured in blood samples of 48 calves at the beginning (day 0) of a feed trial. After 56 days, the calves were assigned (according to weight gain) into three groups: high gainers, medium gainers, and low gainers. Discriminant analysis was used on the variables that were measured to classify the calves into three groups. When the mean values for three overlapping groups of 16 calves each were analyzed, blood urea nitrogen data alone correctly classified 68.7% of the low gainers. Overall, correct classification never exceeded 58.3%. When three nonoverlapping groups of nine calves each were used, inorganic phosphate data (used first and alone) correctly classified 66.7% of the low gainers. After seven steps, 81.5% of the animals were correctly classified, including 88.9% of the low gainers. The two-group discriminant analysis identified 78% of the nine lowest gainers, and 90% of the remaining animals were correctly classified.
Immunofluorescent and Electron Microscopic Studies of Feline Small Intestinal Organ Cultures Infected with Feline Infectious Peritonitis Virus
Authors: Hoshino Yasutaka , Scott Fredric W.
Published: February 2025

The pathogenesis, morphology, and morphogenesis of feline infectious peritonitis virus were studied in feline small intestinal organ cultures. Characteristic coronaviruses were demonstrated by electron microscopy in the extracellular organ culture fluid taken at 1 through 12, 15, 22, 31, and 43 days after the cultures were inoculated. Viral particles had a mean diameter of 94 nm. Numerous petal-shaped projections approximately 15 nm long were seen on the envelopes.

Specific immunofluorescence was detected in the absorptive epithelial cells of villi of small intestinal organ cultures at 1 through 12 days after they were inoculated. By electron microscopy, coronavirus particles were observed entirely in the cytoplasm of the infected columnar epithelial cells of villi with no apparent nuclear involvement. Thin sections of the villous epithelium of small intestinal organ cultures showed a number of ultrastructural alterations, and morphogenesis of feline infectious peritonitis virus in the absorptive epithelial cells of villi was consistent with that for other known human and animal coronaviruses.
Effect of Chronic Lead Exposure on the Canine Bone Marrow
Authors: Mitema Eric S. , Oehme Frederick W. , Penumarthy Lakshmiparthy , Moore William E.
Published: February 2025

The effect of chronic oral lead acetate administration on canine bone marrow was studied. Two dogs (group 1) were used as controls, 4 dogs (group 2) were given 2 mg of lead/kg of body weight daily, and 4 dogs (group 3) were given 5 mg of lead/kg daily. After a 7-day stabilization period, lead dosing was conducted for 91 days (13 weeks), after which half of each group was treated with calcium ethylenediaminetetraacetic acid. All dogs were then observed for another 28 days (4 weeks). Blood lead values and bone marrow cellular changes were monitored once a week during the 126 days (18 weeks) of study. Lead-dosed dogs had lower weight gains than the controls. Clinical signs of toxicosis were observed after 6 weeks in one dog in group 3. Anorexia, body weight loss, cns depression, muscular weakness, and trembling were seen. Blood lead concentrations increased in all group 2 and 3 dogs. Lead caused increases in bone marrow segmented neutrophils and myeloid series cells, and increased myeloid:erythroid ratios. Blood lead concentrations and myeloid:erythroid ratios decreased after cessation of lead administration.
Relation of Antibody-Coated Urine Bacteria to the Site(s) of Infection in Experimental Dogs
Authors: Ling Gerald V. , Ackerman Norman , Ruby Annette L.
Published: February 2025

Antibody-coated bacteria tests, using fluorescein-conjugated rabbit anti-canine immunoglobulin (Ig)G and anti-IgA, were conducted on 77 specimens of bladder urine obtained by antepubic cystocentesis from 25 dogs with urinary tract infections. Urine specimens from 3 dogs infected with Staphylococcus aureus were tested a total of 27 times, specimens from 10 dogs infected with Escherichia coli were tested 25 times, urine from 6 dogs infected with Proteus mirabilis was sampled and tested 18 times, urine from 3 dogs with Klebsiella pneumoniae was sampled and tested 4 times, and specimens from 3 dogs infected with P rettgeri, Enterobacter cloacae, or Streptococcus faecalis were tested once each. Specimens of urine from the renal pelves of each dog were obtained by percutaneous nephropyelocentesis at the same time as the specimens of bladder urine. The results of bacterial cultures of these specimens were compared with the results of the corresponding antibody-coated bacteria tests.

False-positive results (ie, evidence of antibody coating of bladder urine bacteria but no bacterial growth from corresponding renal pelvis urine specimens) were obtained in 13 of 22 (59%) tests of dogs infected with S aureus, 12 of 13 (92%) tests in dogs infected with P mirabilis, 5 of 18 (28%) tests in dogs infected with E coli, and 1 of 4 (25%) tests in dogs infected with K pneumoniae. False-negative results (ie, bacterial growth from renal pelvis urine specimens but no evidence of antibody coating of bacteria in the corresponding specimen of bladder urine) occurred in 5 of 7 (71%) specimens infected with E coli, in 4 of 5 (80%) specimens infected with P mirabilis, and in 5 of 5 (100%) specimens infected with S aureus. It was concluded that the antibody-coated bacteria test does not provide accurate information to support the diagnosis of pyelonephritis in the dog.
Clinical Observations, Cutaneous Lesions, and Hematologic Alterations in Chronic Adriamycin Intoxication in Dogs with and Without Vitamin E and Selenium Supplementation
Authors: Van Vleet John F. , Ferrans Victor J.
Published: February 2025

Chronic adriamycin (adr) intoxication with cardiomyopathy developed in young Beagle dogs given weekly iv injections (1 mg/kg of body weight) for 20 weeks (cumulative dose 400 mg/m2). Eighteen dogs were allotted equally to three groups: group A received adr only, group B was given adr and simultaneous weekly doses of vitamin E (17 mg/kg of body weight as α-tocopherol acetate), and group C received adr, weekly doses of vitamin E as in group B, and selenium (0.06 mg/kg of body weight as selenite). The dogs reacted with cutaneous hyperemia, head shaking, and vomiting immediately after adr injection. After 4 to 6 weekly injections, all the dogs developed alopecia that was present initially over the head and subsequently extended to the ventral portions of the neck, thorax, and abdomen and the proximal inner areas of the limbs. Other skin lesions present in alopecic areas were secondary ulcerative dermatitis and melanosis. Testicular atrophy and cachexia developed in the dogs, but damage was not present in bone marrow, alimentary tract, kidney, and bone with the dosage schedule utilized. Hematologic studies showed no significant alterations. Supplementation with vitamin E alone or with selenium failed to alter the incidence and severity of extracardiac adr-induced lesions. This study shows that the dog is a good model for studies of chronic adr-induced cardiotoxicity, as cardiac damage was consistently produced and adr-associated extracardiac lesions were of minimal severity.
Effect of Neonatal Thymectomy on Pathogenesis of Herpesvirus of Turkeys in Chickens
Authors: Sharma J. Μ. , Lee L. F. , Witter R. L.
Published: February 2025

Effect of immunosuppression on pathogenicity of herpesvirus of turkeys (hvt) in chickens was studied. In three experiments, newly hatched chickens of two genetic strains were surgically thymectomized and γ-irradiated and then exposed to hvt. Lymphoid cells of thymectomized-irradiated chickens had reduced in vitro mitogenic response; this result indicated that the immunosuppressive regimen caused suppression of T cell function. The immunosuppressed chickens had more circulating hvt and had a slightly higher frequency of microscopic lesions in peripheral nerves than the intact control chickens, although the intensity of lymphoproliferation remained very mild and no gross lesions or clinical disease was noted during the 5-week observation period. The absence of significant lesion development in an immunosuppressed host indicated that pathogenic potentials of hvt may be limited.
Heptachlor Residue Accumulation and Depletion in Broiler Chickens
Authors: Wagstaff D. J. , McDowell J. R. , Paulin H. J.
Published: February 2025

Broiler chickens were fed heptachlor in concentrations of 0, 0.01, 0.03, 0.1, and 0.3 mg/kg of the ration for the first 8 weeks of life. There were no adverse effects on health or performance. Residue concentrations in adipose tissue increased rapidly for 1 to 2 weeks and then tended to plateau at concentrations about five times greater than those in the rations. Birds exposed only during the 7th week of life stored 25% as much residue as did the chickens exposed in the 1st week, but the former also ate only 63% as much feed. Fat extracted from liver and muscle contained more residue than did fat extracted from adipose tissue. The ratio of the concentration of heptachlor to its epoxide metabolite was higher in muscle fat than in hepatic or abdominal fat. Residue concentrations depleted by about half in the first 4 weeks after cessation of exposure.
Hemagglutination by Canine Parvovirus: Serologic Studies and Diagnostic Applications
Authors: Carmichael L. E. , Joubert J. C. , Pollock R. V. H.
Published: February 2025

Conditions for canine parvoviral hemagglutination (ha) and hemagglutination-inhibition (hi) reactions were defined. The ha phenomena were used to differentiate canine parvovirus (cpv) from feline panleukopenia virus (fpv), mink enteritis virus (mev), and minute virus of canines. Serologic comparisons of the cpv, fpv, and mev by ha-hi and serum-neutralization tests indicated that cpv, fpv, and mev were antigenically similar but were different from minute virus of canines.

Diagnostic application of ha tests to fecal samples from acute cases of enteritis was discussed. Combining ha tests with hi tests on fecal samples provided a rapid and specific diagnostic method for cpv infection.

Secular seroprevalence studies indicated the emergence of cpv infection in the United States dog population-at-large in 1978.
Experimental Toxoplasmosis in Elk (Cervus canadensis)
Authors: Dubey J. P. , Thorne E. Tom , Sharma S. P.
Published: February 2025

One cow elk (approx 4 months pregnant) and one calf elk were each inoculated intraruminally with 105 infective oocysts of Toxoplasma gondii. Both animals were seronegative when inoculated, but became seropositive to T gondii. Sabin-Feldman dye test antibody titers in relation to days postinoculation were as follows: 1: 1024, 1:1024, and 1:2048 (days 28, 69, and 73) for the calf; 1:2048, 1:128, and 1:128 (days 34, 69, and 73) for the cow; and 1:256 (73 days after inoculation of the cow) for the fetus. Indirect hemagglutination antibody titers were not detected in sera of the cow or her fetus and remained low (1:64 or lower) in calf sera. Both the cow and the calf remained asymptomatic until necropsy 73 days after they were inoculated. Toxoplasma was isolated in mice and cats after they were inoculated with brain, spinal cord, heart, diaphragm, liver, pancreas, cervical lymph nodes, and intestines of the infected calf; with brain, heart, diaphragm, and skeletal muscles of the infected cow; and with brain, heart, cervical lymph nodes, and spleen of the fetus.
Tissue Concentrations of Mast Cells and Lymphocytes of the Bovine Uterine Tube (Oviduct) During the Estrous Cycle
Authors: DuBois Jeffrey A. , Wordinger Robert J. , Dickey Joseph F.
Published: February 2025

Estrous cycle fluctuations in the mast cell and lymphocyte counts (per mm2 of tissue) of the ampulla and isthmus of the bovine uterine tube (oviduct) were determined. Four random sections of each region of the uterine tube were prepared at 2 μm thickness and stained with toluidine blue.

The mast cell count of the isthmus was found to be significantly higher (P < 0.01) than the mast cell count of the ampulla for all stages of the estrous cycle. A significant increase (P < 0.01) in the mast cell value of the isthmus occurred during metestrus, diestrus, and proestrus. In the ampulla, metestrous and diestrous mast cell numbers were significantly higher (P < 0.05) than mast cell numbers during estrus. The lymphocyte numbers remained relatively constant in both the ampulla and the isthmus except during diestrus, when ampullary lymphocyte numbers increased significantly (P < 0.05). Lymphocytes were observed to migrate through the uterine tube epithelium and mast cells were observed only in the lamina propria.
Electromagnetic Measurement of Cardiac Output During Exercise in the Horse
Authors: Waugh S. L. , Fregin G. F. , Thomas D. P. , Gerber N. , Grant B. D. , Campbell K. B.
Published: February 2025

Aortic root blood flow was measured with an electromagnetic (em) flow meter in unanesthetized horses during rest and exercise. The cardiac output response to exercise, as determined by the em technique, was compared with the response reported by others who used indicator dilution techniques with good agreement. The em method will allow making measurement of cardiovascular responses to exercise in the horse, not obtainable with other techniques.
Enzyme-Linked Protein A: An Enzyme-Linked Immunosorbent Assay Reagent for Detecting Antibodies in Tuberculous Exotic Animals
Authors: Thoen Charles O. , Mills Ken , Hopkins Mary P.
Published: February 2025

An enzyme-linked immunosorbent assay (elisa) was developed, using protein A labeled with horseradish peroxidase for detecting antibodies in tuberculous exotic mammals (llamas, rhinoceroses, elephants). The modified elisa provides a rapid procedure for screening several animal species simultaneously for tuberculosis without the production of specific antispecies conjugates. Heat-killed cells of Mycobacterium bovis and Μ avium and purified protein-derivative tuberculin of Μ bovis were used as antigens for elisa.
Establishment of a Canine Cell Line: Derivation, Characterization, and Viral Spectrum
Authors: Binn L. N. , Marchwicki R. H. , Stephenson Ε. H.
Published: February 2025

A cell line, designated A-72, for virus studies was established from a tumor surgically removed from a female, 8-year-old Golden Retriever dog. Following explant culture, the cells were serially passaged 135 times. The A-72 cells maintained a fibroblastic appearance and, at the 123rd passage, had a population doubling time of approximately 27 hours. Karyotypic analysis of the high passage cells showed the modal 2n chromosome number was 92 to 93. Using starch gel electrophoresis for enzyme characterization, the electrophoretic mobilities of enzymes extracted from A-72 cells were identical with those of canine peritoneal fibroblasts and primary canine kidney cells. The A-72 cells were susceptible to infection with infectious canine hepatitis virus, canine adenovirus type II, canine herpesvirus, canine parainfluenza virus, and canine coronavirus, but were not susceptible to canine distemper virus or the minute virus of canines. These cells have been particularly useful for studies of the fastidious canine coronaviruses, as the commonly used primary canine kidney cells exhibit varied susceptibility to these viruses.
Reaginic Hypersensitivity in Otodectes cynotis Infestation of Cats and Mode of Mite Feeding
Authors: Powell M. B. , Weisbroth S. H. , Roth L. , Wilhelmsen C.
Published: February 2025

Otodectes cynotis infestations were induced in barrier-reared mite-free cats. By monitoring the infested cats, sequence of humoral and cellular immune reactions to the mites was determined. Delayed hypersensitivity was not demonstrated in vivo, using intradermal skin tests. Reaginic (immunoglobulin E) antibodies, as detected by 72-hour passive cutaneous anaphylaxic reactions, were the earliest form of immune expression. Precipitating antibodies developed later in the course of the experimental infestation. Hematologic indices, including eosinophil counts, were not affected by established infestations.

Antibodies prepared against feline whole blood, lymph, epithelium, and rbc indicated that these regularly occurred in extracts prepared from whole mites. It was concluded, therefore, that the feeding mode of mites required that they ingest feline tissue fluids. This mode is the interface by which the host becomes exposed to, and immunized against, mite antigens.
Experimental Infection of Domestic Goats with Fascioloides magna
Authors: Foreyt William J. , Leathers C. W.
Published: February 2025

Development of the deer liver fluke, Fascioloides magna, was studied in seven domestic goats, each experimentally inoculated with 250 metacercariae. Six infected goats died between 89 and 195 days (mean 139) after inoculation. Infection did not develop in the seventh goat. Mortality was the result of unrestricted fluke migration before maturation or encapsulation of the flukes. A total of 144 F magna (mean intensity of 24.0) were recovered from inoculated goats, representing 8.2% of the metacercariae administered. Growth rate of F magna in goats was similar to that in cattle, white-tailed deer, and sheep.
Effects of Level of Nitrogen Fertilization of Fescue Pasture on Gastrointestinal Parasitism of Beef Cattle
Authors: Ciordia H. , Stuedemann J. A. , Ernst J. V. , McCampbell H. C. , Wilkinson S. R.
Published: February 2025

Two established tall fescue pastures were used in a 4-year study of the relationship between the level of gastrointestinal parasitism in cattle and the level of nitrogen fertilization of the pasture. One pasture was fertilized with 224 kg of NH4NO3/ha each year and served as the control. A second pasture, referred to as the low-fertilized (lf) pasture, was fertilized with Ν at 84 kg/ha the first year and 74 kg/ha in each of the next 3 years. Both pastures were stocked with Angus cows (2.5/ha) and their calves. Rectal fecal samples obtained every 6 weeks from 10 cows and as many calves as possible in each pasture were examined for nematode eggs and coccidia oocysts. Two calves from each group were slaughtered at the end of each of the last 3 years to determine the numbers and species of parasites. Cows had significantly lower egg counts than did the calves. Egg counts did not differ between the two groups of cows, but the control cows had higher average weights than the cows on the lf pasture. Control calves had significantly lower egg counts than the calves on the lf pasture, but only slightly higher mean adjusted 205-day weights. At necropsy, significantly fewer worms were recovered from the controls (17,977) than from the lf-pastured calves (52,332). Cooperia oncophora was the predominant species. The level of coccidia infection did not differ between the two groups of cows and calves. The greater availability of forage in the control than in the lf pasture probably was responsible for the lower level of parasitism in the control calves and for the greater weight gains made by the control cows and calves.
Hyperlipemia in Horses: Effects of Undernutrition and Disease
Authors: Naylor J. M. , Kronfeld D. S. , Acland Helen
Published: February 2025

Lipid mobilization was followed in a study of healthy horses in which food but not water was withheld for 120 hours. The rise in serum lipids was consistent with an initial release of free fatty acids and glycerol from adipose tissue. This was followed by a rise in serum triglyceride as the liver took up free fatty acids and converted them to triglycerides. Changes in total lipids reflected increases in individual serum lipid constituents, especially triglycerides which underwent the greatest absolute increase during food deprivation. The concentration of many serum lipids increased until a new steady state was reached, presumably the point at which increased production was balanced by removal. Numerical values for free fatty acids were 1.61 ± 1.84 (mean ± sd) and 27.78 ± 8.24 mg/dl in fed and food-deprived horses at plateau, respectively; triglyceride values were 31.12 ± 6.86 and 194.7 ± 79.5 mg/dl, respectively.

Observations of healthy horses showed that serum triglyceride concentration rose to a variable extent and with a delay of at least 40 hours after food deprivation. Studies of sick horses confirmed that hypertriglyceridemia was associated with hypophagia, but that the converse was not always true. Thus hypophagia may exist without concomitant hypertriglyceridemia, but the presence of hypertriglyceridemia was a sound indicator of pre-existing hypophagia.

A few sick horses had hyperlipemia. These had very high serum lipid concentrations (up to 3,000 mg of triglyceride/dl), cloudy serum, and fatty infiltration of the liver. There was a statistically significant, Ρ < 0.001, association between serum creatinine and triglyceride concentrations. We postulated that a metabolic block in the removal of triglyceride from serum existed in azotemic horses and that this exacerbated the effect of hypophagia on serum lipid concentrations.
Prolonged Bleeding Time in Aleutian Mink Associated with a Cyclo-Oxygenase-Independent Aggregation Defect and Nucleotide Deficit in Blood Platelets
Authors: Bell Thomas G. , Padgett George A. , Patterson Wayne R. , Meyers Kenneth M. , Gorham John R.
Published: February 2025

A prolonged mean template bleeding time of 13 minutes was present in nine Aleutian mink affected with Chediak-Higashi syndrome (chs) compared with 4 minutes in dark control mink. The concentrations of blood platelets in normal and affected animals did not differ significantly. However, in mink with chs, a marked disturbance of platelet response to collagen was present. Administration of aspirin and indomethacin completely blocked ch platelet response to collagen. Blood platelet adenosine triphosphate and adenosine diphosphate values from mink with chs were significantly less than those of normal mink, and the platelet adenosine triphosphate/adenosine diphosphate ratios were 10.31 in affected mink and 2.74 in normal mink. These findings are consistent with our previous investigations in affected cattle and persons and indicate that a “storage pool disease” of platelets exist in the mink with chs.
Cell-Mediated Immunity Against Turkey Coronaviral Enteritis (Bluecomb)
Authors: Nagaraja Κ. V. , Pomeroy B. S.
Published: February 2025

Studies on cell-mediated immune response in turkeys infected with turkey coronavirus (tcv) were made. A whole blood culture technique was developed for quantitatively evaluating in vitro lymphocyte reactivity to mitogens concanavalin A, phytohemagglutinin-P, and tcv antigen. The degree of blastogenesis was quantitated by the measurement of the uptake of the [125I]deoxyuridine in the presence of fluorodeoxyuridine. The stimulation indices were consistently higher in the infected birds compared with those in the noninfected controls, and they were statistically significant (P < 0.05). The detection of tcv specific responses indicated that cell-mediated immunity may be important in determining the immunity against turkey coronaviral enteritis. The whole blood lymphocyte transformation assay was emphasized as a convenient and useful in vitro indicator of cell-mediated immunity in tcv infection.
Preliminary Studies on Transmission of Chlamydia to Cattle by Ticks (Ornithodoros coriaceus)
Authors: McKercher D. G. , Wada Ε. M. , Ault S. K. , Theis J. H.
Published: February 2025

Preliminary findings indicate that Ornithodoros coriaceus ticks can harbor Chlamydia for long periods and are able to transmit the agent to cattle. Field-collected O coriaceus ticks, which were infected experimentally with a bovine chlamydial agent from an aborted fetus, transmitted the agent 25 and 48 days later to three pregnant heifers. Two of these heifers aborted and the third delivered a term calf. The control heifer also aborted after intradermal (simulated tick) exposure.

Also, a chlamydial agent was isolated from field-collected O coriaceus ticks in an epizootic bovine abortion (eba)-enzootic area that were held for at least 6 months. In the same enzootic area, a chlamydial agent was isolated from a prematurely delivered calf during a severe eba outbreak. Seemingly, this species is a cause, if not the cause, of eba.
Osmolarity and Volatile Fatty Acid Content of Feces from Horses with Chronic Diarrhea
Authors: Merritt A. M. , Smith Doris A.
Published: February 2025

The concentrations of acetate (C2), propionate (C3), isobutyrate (iC4), butyrate (nC4), isovalerate (iC5), and valerate (nC5) were measured in the feces of 16 clinically normal horses and 44 horses with chronic diarrhea of at least 1-month's duration. The diarrheal horses were categorized diagnostically as: (1) no discernible clinical abnormalities other than diarrhea and in some cases, weight loss (open); (2) clinical evidence of strongyle larval migrans; and (3) Salmonella organisms recovered from the feces. Osmolarity of the feces of 14 of the normal and 15 of the sick horses also was measured. The mean concentration of C2 was significantly less (P < 0.05) in feces from horses of all diagnostic categories, whereas there was a significantly increased isobutyrate concentration (P < 0.01) in feces from horses in the open category. When individual volatile fatty acids (vfa) were expressed as percentage of total, only isobutyrate in feces from horses in the open category was significantly different (P < 0.01) from normal and was increased.

Some horses were monitored sequentially for a number of weeks. Fecal vfa concentrations showed considerable variability, and a transient decrease of isobutyrate concentration was not necessarily coincidental with cessation of diarrhea. Horses responding to empirical therapy had a more stable reestablishment of a normal fecal vfa distribution. Correlation between total fecal vfa concentration and osmolarity was significant (P < 0.05) for diarrheal horses, but was not significant for normal horses.
Alterations in Horse Blood Cell Count and Biochemical Values After Halothane Anesthesia
Authors: Steffey E. P. , Farver T. , Zinkl J. , Wheat J. D. , Meagher D. M. , Brown M. P.
Published: February 2025

Quantitative changes in hematologic and serum biochemical values associated with prolonged general anesthesia produced by known alveolar doses of halothane in oxygen were determined in six young, healthy horses under laboratory conditions. In addition, 25 young equine patients anesthetized for shorter periods under clinical conditions were similarly (except hematologic values) prospectively evaluated. In normal horses, muscle- and hepatic-derived serum biochemical values were mildly increased immediately after anesthesia. Values after anesthesia remained at greater than base-line values for up to 4 days. Evidence of minimally depressed renal function was also present immediately after halothane exposure but did not persist beyond the first day.
Clinical Approach to Determine the Contribution of the Palmar and Palmar Metacarpal Nerves to the Innervation of the Equine Fetlock Joint
Authors: Gray B. W. , Engel H. N. , Rumph P. F. , LaFaver J. , Brown B. G. , McKibben J. S.
Published: February 2025

To determine the sensory nerve supply of the metacarpophalangeal joint, lameness was induced in eight horses by injecting the joint with a glycerin suspension of glass microspheres. When the medial and lateral palmar nerves were anesthetized in 4 horses, there was noticeable improvement in the gait, but each horse remained lame. When the medial and lateral palmar metacarpal nerves were also anesthetized, 3 of the 4 horses became sound. To confirm the results of local anesthesia, neurectomies were performed on a second group of four horses. The lameness was alleviated only upon resection of both the palmar nerves and the palmar metacarpal nerves.
Induced Juglone Toxicosis in Ponies and Horses
Authors: True R. G. , Lowe J. E.
Published: February 2025

Juglone, a toxic compound found in all parts of plants of the walnut tree family Juglans, was evaluated as the possible toxin involved in black walnut shaving-associated laminitis in the horse. Large amounts (up to 1 g) of this chemical administered per os inconsistently caused mild signs of laminitis in ponies. Topical application of juglone to the digits of horses caused local skin irritation but did not cause laminitis. Intravenous administration of juglone caused acute pulmonary edema in some individuals previously exposed to the compound per os or iv.
Determining Time of Death of a Dog by Analyzing Blood, Cerebrospinal Fluid, and Vitreous Humor Collected at Postmortem
Authors: Schoning Polly , Strafuss A. C.
Published: February 2025

Blood, cerebrospinal fluid, and vitreous humor collected at antemortem and postmortem from 60 dogs were analyzed to determine what chemical value may be used for estimating time of death. Euthanatized dogs were maintained at 4 C, 20 C, or 37 C for 3, 6, 12, 24, or 48 hours.

At postmortem, vitreous humor potassium values increased with increased time and increased temperature. Cerebrospinal fluid chloride values decreased; potassium and phosphorus values increased markedly, and calcium and creatinine values increased slightly. Blood potassium, phosphorus, and creatinine values increased; sodium and chloride values decreased. Within 6 hours after death, blood carbon dioxide values decreased to a quarter of values determined at antemortem.
Infrared Photographic Measurement of Pupillary Effects of Dichlorvos in Beagles
Authors: Wagstaff D. J. , Winston F. B.
Published: February 2025

Dichlorvos was given orally to Beagles at dose rates of 13.5, 27, and 40.5 mg/kg of body weight. Pupillary response to a strobe flash was observed by using infrared cinematography. In dogs given the two larger dosages, the pupil contracted to a smaller size than it had been before treatment (base line) and recovered more slowly to base-line diameter.
Influence of Time Interval Between Administration of Chloramphenicol and Thiamylal on the Sleeping Time of Mice
Authors: Azadegan Aliakbar , Johnson Donald W. , Stowe Clarence M.
Published: February 2025

The influence of the time interval between chloramphenicol and thiamylal administrations on the sleeping time of mice was studied. Two hundred 20- to 25-g mice were given (intraperitoneally) chloramphenicol or isotonic saline solution and then thiamylal at different time intervals between drugs. The duration of anesthesia was measured as the time between the loss and the return of the righting reflex. The results indicated that in mice given chloramphenicol simultaneously with thiamylal (0 time interval), the sleeping time was increased by a factor of about 10 as compared with the sleeping time in mice given thiamylal alone. As the time interval between administrations of thiamylal and chloramphenicol was increased (from 0.25 to 4 hours), the prolongation of sleeping time decreased correspondingly.
Study of Bovine Pulmonary Response to Pasteurella haemolytica: Pulmonary Macrophage Response
Authors: Walker R. D. , Corstvet R. E. , Panciera R. J.
Published: February 2025

A resistant state was produced in the bovine lung by exposing calves to an aerosolized mist of Pasteurella haemolytica. Verification of the resistant state was determined by an increase in clearance of Ρ haemolytica from lungs of exposed calves vs lungs from nonexposed calves over 24 hours. Bovine pulmonary macrophages isolated from lung washings of calves exposed to Ρ haemolytica and from lungs of nonexposed calves failed to phagocytize Ρ haemolytica in vitro. Whole serum, pulmonary immunoglobulin (Ig)A, and IgG from exposed and nonexposed calves did not enhance phagocytosis as measured by 14C uptake or fluorescent antibody staining.
Study of Bovine Pulmonary Response to Pasteurella haemolytica: Specificity of Immunoglobulins Isolated from the Bovine Lung
Authors: Walker R. D. , Corstvet R. E. , Lessley B. A. , Panciera R. J.
Published: February 2025

A procedure is described for the isolation and purification of the immunoglobulins (Ig)A and IgG from pulmonary lavage fluid from calves. These Ig were isolated from calves experimentally exposed to Pasteurella haemolytica via aerosolization and from nonexposed calves. The specificity of these fractions toward Ρ haemolytica was examined, using an indirect fluorescent antibody test and agglutination reactions. Specific antibody activity was detected in the IgA and IgG fractions from calves exposed to Ρ haemolytica and IgG fractions from nonexposed calves. None of the isolated Ig agglutinated Ρ haemolytica.
Embryo Transfer in Cattle: Nonsurgical Transfer
Authors: Rowe R. F. , Del Campo M. R. , Critser J. Κ , Ginther O. J.
Published: February 2025

Four experiments were conducted to define reasons for failure of nonsurgical transfer of bovine embryos. Single embryos were transferred to the uterine horn ipsilateral to the corpus luteum-bearing ovary 6 to 9 days after estrus. All recipient heifers were within ± 24 hours of heat synchrony with the donors. All nonsurgical transfers were accomplished, using the Cassou apparatus with 0.5 ml French straws. Pregnancy was determined by rectal palpation on day 40 (31 to 34 days after transfer).

In experiment 1, when embryos were transferred surgically, pregnancy rates were not different between the midventral approach (11/14, 77%) and the flank approach (10/14, 71%) but were lower (P < 0.05) when transfers were done nonsurgically (3/14, 36%). In experiment 2, transfer to the midportion of the uterine horn was compared with transfer to the cranial end of the uterine horn. Embryo survival in the midportion of the uterine horn tended to be higher (P < 0,06) when embryos were placed nonsurgically (15/20, 75%) than when transfer was accomplished surgically (9/20, 45%). Surgical transfer to the midportion of the uterine horn was not affected by sham nonsurgical manipulation. Pregnancy rate was not different between nonsurgical transfer to the middle portion of the uterine horn (15/20, 75%) and surgical transfer to the cranial portion (12/20, 60%). In experiment 3, pregnancy rate was not affected by digital compression to the uterine horn during withdrawal of the Cassou instrument after nonsurgical transfer. Pregnancy rates in experiment 4 were not different between the midportion of the uterine horn and the caudal portion of the uterine horn, using nonsurgical embryo transfer.

An operator experienced in nonsurgical embryo transfer obtained higher pregnancy rates (23/40, 58%) than did an operator with no previous nonsurgical embryo transfer experience (14/40,35%, Ρ < 0.05). Amount of time to penetrate the cervix did not affect transfer results; however, increasing the time that the Cassou catheter remained in the uterus tended to decrease pregnancy rates (P < 0.07). It is concluded that experience in nonsurgical transfer is important in achieving acceptable success rates and that specific regional placement of the embryo in the uterine horn ipsilateral to the corpus luteum-bearing ovary is not imperative for nonsurgical transfer success.