bluuebunny/crossref_metadata_2025 huggingface dataset:
Isolation and functional analysis of normal canine blood monocytes and resident alveolar macrophages
Authors: Shaw S. E. , Anderson Ν. V.
Published: February 2025

The percentage of mononuclear phagocytes bearing the Fc receptor for immunoglobulin G, the percentage of cells phagocytic for Candida albicans and latex particles, and the phagocytic index for blood monocytes and alveolar macrophages from healthy dogs are reported. Blood monocytes were concentrated by density-gradient centrifugation, whereas alveolar macrophages were obtained in high yield by bronchoalveolar lavage. Adherent populations of those cells were used for functional assays after repeated washing to remove nonadherent cells. A greater percentage of adherent alveolar macrophages than adherent blood monocytes showed evidence of the Fc receptor for immunoglobulin G. Similarly, adherent alveolar macrophages showed significantly greater phagocytic ability, as measured by percent phagocytic cells and phagocytic index, using C albicans and latex particles, than did adherent canine blood monocytes.
Xylazine causes transient dose-related hyperglycemia and increased urine volumes in mares
Authors: Thurmon J. C. , Steffey E. P. , Zinkl J. G. , Woliner M. , Howland D.
Published: February 2025

Xylazine given iv at doses of 0.5, 1.0, and 1.5 mg/kg to mares caused a significant (P < 0.05) dose-related increase in serum glucose concentration and urine volume. Serum glucose concentrations as much as 150 mg/dl were recorded in mares after they were given the largest xylazine dose. The greatest urine volume, similar to changes in peak glucose concentration, always occurred during the first hour after dosing with xylazine and averaged 1.82, 3.93, and 5.68 ml/kg/hour after the 0.5-, 1.0-, and 1.5-mg/kg doses, respectively, were given. Urine osmolality and specific gravity were significantly (P < 0.05) inversely related to urine volume. Although serum glucose concentrations were significantly increased above those measured after iv injection of saline solution, significant glucosuria was not detected.
Infestation potential of Psoroptes ovis (Hering) from cattle injected with ivermectin
Authors: Wright Fred C. , Guillot Frank S.
Published: February 2025

Cattle scabies mites, Psoroptes ovis (Hering), surviving on cattle injected subcutaneously with ivermectin were capable of infesting to unprotected cattle 3, 5, 7, and 9 days after injection. All recipient cattle exposed to mites from vehicle-injected cattle developed reproductive colonies in 5 weeks. All recipient cattle exposed to mites from ivermectin-injected cattle at 3 and 5 days after injection developed reproductive colonies in 5 weeks. By 8 weeks, 3 of 4 and 2 of 4 recipient cattle exposed to mites from ivermectin-injected cattle 7 and 9 days after injection, respectively, developed reproductive colonies. To prevent the spread of mites, injected cattle should be isolated from uninfested cattle for longer than 9 days.
Lymphocyte reactivity to Ostertagia ostertagi L3 antigen in type I ostertagiasis
Authors: Klesius Phillip H. , Washburn S. Michelle , Ciordia Honorico , Haynes Thomas B. , Snider Theron G.
Published: February 2025

To better understand the immune response of calves infected with Ostertagia ostertagi, studies were conducted to examine cell-mediated immune responses to L3 antigen and phytohemagglutinin (pha) by lymphocyte reactivity assay. The L3 antigen was prepared by freeze-thawing and sonication of exsheathed O ostertagi L3. Antigen preparations contained 40 to 60 µg of protein/ml and no detectable endotoxin.

Cell-mediated immune responses of peripheral blood lymphocytes were determined in 3 groups of 12 calves each: (i) calves given consecutive multiple dose inoculations with L3; (ii) calves naturally infected by pasture exposure to L3; and (iii) noninfected controls. Consecutive multiple-dose-inoculated calves showed marked increases in stimulation indices (si) to L3 antigen over the si of naturally inoculated calves (56.5 and 25.8, respectively). Negative si were obtained in calves of the noninoculated control group (−1.0). No significant difference (P ≥ 0.05) in response to pha was obtained between lymphocytes from calves inoculated with O ostertagi and lymphocytes obtained from noninoculated control calves. There was significant (P ≤ 0.01) agreement between positive si and evidence of patent infection (development of type I ostertagiasis).

Specificity of lymphocyte reactivity was determined, using lymphocytes from 4 O ostertagi- and 2 Cooperia punctata-infected calves after challenge inoculation. Positive si to L3 antigen were obtained, using lymphocytes from either O ostertagi- or C punctata-infected calves, indicating that there may be a lack of genus specificity for O ostertagi L3 antigen in lymphocyte reactivity assay.

Kinetic studies of lymphocyte reactivity to L3 antigen and pha showed that responses were briefly suppressed to both of these stimuli in prepatent calves. It was concluded that transient nonspecific suppression of cell-mediated immune responses occurs during prepatent periods of type I ostertagiasis. This immunosuppression phenomenon may have a role in the pathogenesis of O ostertagi and in development of immunity to ostertagiasis.
Tonsillar changes in pigs given pseudorabies (Aujeszky's disease) virus
Authors: Narita Minoru , Inui Sumio , Shimizu Yukio
Published: February 2025

All of the eight 5-day-old pigs orally given pseudorabies (Aujeszky's disease) virus developed tonsillitis. The initial changes occurred in the subepithelial area between the lymphoid nodule and the crypt epithelium, showing a characteristic pattern of necrosis. The necrosis became more severe and gained access into the lymphoid nodule and crypt epithelium. Coincident with the histopathologic changes, numerous specific immunofluorescences were detected, first in the nucleus and in some parts of the cytoplasm of cells distributed in the subepithelial area. The fluorescence subsequently spread into adjacent lymphoid nodules and crypt epithelial cells. Ultrastructurally, many enveloped virus particles were detected in the center of the necrosis. Thereafter, the crypt epithelial cells also underwent degeneration, and a small number of virus particles were detected in the nucleus of the degenerating epithelial cells. In the more advanced stage, the enveloped virus particles were discharged into the crypt lumen.
Relationship of iron administration to susceptibility of newborn pigs to enterotoxic colibacillosis
Authors: Kadis Solomon , Udeze Frank A. , Polanco José , Dreesen David W.
Published: February 2025

To determine whether supplemental iron (Fe) administration to newborn pigs reared in concrete pens not only prevents anemia, but renders the pigs more susceptible to Escherichia coli-induced diarrheal disease, pigs were given a large or a small dose of Fe im or orally before or after challenge exposure with E coli. The controls were challenge-exposed pigs not given Fe and pigs not challenge exposed (Fe-treated and nontreated groups).

Although the mortality of the pigs challenge exposed with E coli and administered a large oral dose of Fe shortly after birth was greater than that of the challenge-exposed pigs given no Fe, differences in mortality were not noted between any of the groups tested when the Fe was injected im. The Fe-treated survivors had severe diarrhea (oral Fe administration) or mild diarrhea (im Fe administration) for longer periods than did the nontreated survivors. All challenge-exposed pigs treated with a large dose of Fe gained less weight than the nontreated pigs during the diarrheal period and for several days thereafter. Beyond this time period, the weight gain of the Fe-treated pigs was substantially greater than that of their nontreated littermates; the weight gain of the pigs given a small dose of Fe was intermediate.

Hemoglobin and hematocrit values of the pigs shortly after birth and weekly thereafter revealed that within 2 weeks, both sets of values from the pigs treated with a large dose of Fe were within acceptable laboratory limits and substantially greater than the values obtained for the nontreated pigs, which were severely anemic.
Clinical and laboratory characterization of Basenjis with immunoproliferative small intestinal disease
Authors: Breitschwerdt Edward B. , Ochoa Ricardo , Barta Marketa , Barta Ota , McClure Jill , Waltman Celeste
Published: February 2025

Eleven adult Basenji dogs with immunoproliferative small intestinal disease (ipsid) were studied. Two items of history related to the digestive tract were characteristic: (i) chronic intractable diarrhea in most dogs, and (ii) progressive emaciation. Anorexia was intermittent in only a few dogs. In addition, skin lesions of various degrees of severity were observed, including alopecia of pinnae and ventrum, hyperpigmentation and hyperkeratosis of pinnae, and necrosis and ulcerations of margins of pinnae. The cause of the skin lesions was not determined; however, hypothyroidism did not appear to contribute to the skin changes.

Standard hematologic and serum chemical values were not consistently abnormal. However, a poorly regenerative anemia, mild neutrophilia, and increased aspartate aminotransferase and alanine aminotransferase activities were generally observed in severely affected dogs. The Pelger-Huet anomaly was identified in dog 3.

Maldigestion and malabsorption as determined by the N-benzoyl-l-tyrosyl-p-aminobenzoic acid and d-xylose test was documented to varying degrees in dogs with ipsid. Maldigestion was correlated with functional pancreatic exocrine insufficiency. Severe malabsorption was documented in only 3 dogs.

Serum gastrin values were evaluated in these dogs because of a prior observation of parietal cell hyperplasia and gastric ulceration. Hypergastrinemia was documented in 3 dogs. Additional studies will be necessary to determine whether an acid hypersecretory state contributes to the pathogenesis of ipsid in Basenjis.
Antisperm responses in male dogs with chronic Brucella canis infections
Authors: George Lisle , Carmichael Leland
Published: February 2025

Male Beagles infected with Brucella canis for ≥ 3 months developed serum antibodies that agglutinated normal canine spermatozoa. Titers were highest in dogs that had been infected for 4 to 6 months. Lower spermagglutinin titers were detected in sera collected 10 months after inoculation. Antibodies were also observed in seminal plasma of chronically infected dogs. Seminal plasma from infected, but not from clinically normal dogs, caused head-to-head agglutination of normal sperm. In contrast to macroagglutination of sperm by serum antibodies, agglutination by seminal plasma antibodies was detected only by microscopic examination. Seminal plasma agglutinins were not inactivated by heat (56 C, 1 hour) or by reduction with 2-mercaptoethanol. When seminal plasma and sperm were mixed with 2 hemolytic units of guinea pig complement, spermatozoa were not inactivated. Spermagglutinin activity was present in the first 2 spectral absorption peaks of Sephadex G-200 fractionated seminal plasma. Fractions that had the highest spermagglutinin titers contained mostly immunoglobulin A.

Seminal plasma from infected dogs also contained cytophilic factors for normal splenic macrophages that caused sperm adherence to macrophages.

Dogs with a bacteremia lasting > 4 months had cutaneous delayed-type hypersensitivity reactions when tested with soluble canine testicular extracts. Reactions did not occur in normal dogs. Dogs with testicular atrophy had the most severe skin test responses. Seemingly, isoimmune responses to sperm antigens are involved in infertility caused by B canis infection of male dogs.
Surgical and chemical vasectomy in the cat
Authors: Pineda M. H. , Dooley M. P.
Published: February 2025

Ejaculates of surgically vasectomized cats had spermatozoa as long aa 49 days after vasectomy, indicating that spermatozoa in the ejaculate from intact cats originated from the epididymides and vasa deferentia.

Intraepididymal injections of an aqueous solution of 4.5% chlorhexidine digluconate into the caudae of the epididymides induced a lasting oligospermia or azoospermia in 7 of 8 cats. Of these 7 cats, 4 were azoospermic and 1 cat had no intact spermatozoa in his ejaculates 140 days after treatment. The method of chemical vasectomy by intraepididymal injection of sclerosing agents appears to be safe and may be suitable for large-scale sterilization programs for controlling the growth of the feline population.
Rates of diagnosis of six diseases of Holstein cows during 15-day and 21-day intervals
Authors: Erb Hollis N. , Smith R. David , Hillman Robert B. , Powers Pamela A. , Smith Mary C. , White Maurice E. , Pearson Erwin G.
Published: February 2025

The lactations of 3,172 Holstein dairy cows were divided into intervals of 15 and 21 days. The numbers of new diagnosis of metritis, cystic ovary, miscellaneous reproductive disorders, mastitis, left displaced abomasum, and milk fever in each interval were counted. The numbers of cows at risk in each interval were also counted. A cow was at risk if she was still milking, in the herd, and a diagnosis had not already been made for that condition in that lactation. A cow was also only at risk of a reproductive diagnosis if she was not pregnant. For each interval, the incidence rate of new diagnoses was calculated by dividing the number of new diagnoses by the number of cows at risk.
Pulmonary function testing in calves: Technical data
Authors: Lekeux P. , Hajer R. , Breukink H. J.
Published: February 2025

Measurements of airflow (V̇), tidal volume (Vt), and intrapleural pressure (Ppl) were tested for accuracy in 5 healthy Dutch Friesian calves with an average body weight of 153 kg. A face mask was constructed, using fiberglass and polyester, taking into account the typical facial morphology of the calf. It was tested for airtightness, dead space, laminarity of the expiratory V̇, and absence of saliva into the pneumotachograph. Three different systems for measuring Ppl (pleura puncturing, esophageal bailloon catheter, and esophageal saline solution-filled catheter) were tested in vitro, in a Woulfe's flask, and in vivo, in the 5 calves previously described. Moreover, Ppl measured at 3 different puncture sites of the thorax and at 3 different thoracic positions of the esophagus were compared.

The frequency-response was flat to 5 Hz for the intrapleural needle and the balloon catheter, but not for the saline solution-filled catheter. The pulmonary function values obtained by puncture of the pleura at the right 9th intercostal space on a line running from the tuber coxae to the shoulder joint and by the esophageal balloon catheter, the balloon being positioned between the crossing point with the aorta and the 2 largest caudal mediastinal lymph nodes, did not differ significantly. The Ppl changes during normal breathing were greatest in the ventral site of the thorax and in the caudal thoracic portion of the esophagus, less in the dorsal site of the thorax and the middle thoracic portion of the esophagus, and least in the cranial site of the thorax and the cranial thoracic portion of the esophagus. When the balloon was positioned between the crossing point with the aorta and the 2 largest caudal mediastinal lymph nodes, Ppl recordings showed a twice smaller variability than with the 2 other esophageal positions.
Virulence in African swine fever: Its measurement and implications
Authors: Pan I. C. , Hess W. R.
Published: February 2025

A method of measuring and expressing the virulence of African swine fever virus in numerical terms was developed. Seventeen viruses (13 hemadsorbing and 4 nonhemadsorbing) were tested and classified into 3 groups: highly infectious and highly virulent, highly infectious and moderately virulent, and slightly infectious and slightly virulent. This classification was based on the number of 50% hemadsorption unit (ha50) or tcid50 required to produce 1 ld50 for swine, the number of ha50 or tcid50 required to produce one 50% pig infectious dose (pid50), and the number of pid50 required for each ld50.

The virulent virus (group 1) required ≤ 10 virus units (ha50 or tcid50) for 1 pid50 and ld50 (highly infectious and highly lethal), respectively, and had a ratio of 1.0 for pid50/ld50, ie, all infected pigs died from acute African swine fever. Tengani, L'60, and DR-I isolants and nonhemadsorbing viruses of Haiti-1 isolant belong to this group.

The moderately virulent virus (group 2) required < 10 virus units for 1 pid50 and 20 to 562 virus units for 1 ld50 (highly infectious and moderately lethal), respectively, and recoveries from the clinical disease and immunologic deaths were frequent. Madrid '75, Haiti-1, DR-II, and BR-I isolants belong to this group.

The slightly virulent virus (group 3) required 56 to 10,000 virus units for 1 pid50 and 56,200 to 3,120,000 virus units for 1 ld50 (slightly infectious and less lethal). The L'60BM89BC1 virus, which originated from Portugal as a vaccinal virus, and L'60BM89BC20-2 virus, which was obtained from L'60BM89BC1 virus by 20 subpassages at limiting dilution, belong to this group. The nonhemadsorbing viruses isolated from the moderately virulent Haiti-1 isolant were highly infectious and highly virulent. Their nonhemadsorbing and virulent characteristics were genetically stable.

The virulence of a virus preparation was determined by the proportion of highly virulent and slightly virulent, and possible moderately virulent, clones in the preparation at the time of testing. Observations on the clinical disease caused by viruses of a varying virulence were described and implications were discussed.
Pemphigus in the dog: Comparison of immunofluorescence and immunoperoxidase method to demonstrate intercellular immunoglobulins in the epidermis
Authors: Suter Maja M. , Palmer Dieter G. , Zindel Sibylle , Schenk Helen
Published: February 2025

In 3 dogs with pemphigus vulgaris and 4 dogs with pemphigus foliaceus, intercellular immunoglobulins were demonstrated in the epidermal stratum spinosum. The immunofluorescence technique on cold ethanol-fixed and paraffin-embedded tissue sections was compared with the immunoperoxidase method on formalin-fixed paraffin-embedded tissue sections. The results of both methods were identical. However, the advantage of the unlabeled antibody-enzyme method was that the same formalin-fixed tissue specimens could be used for conventional light microscopy, as well as for immunohistologic studies.
Cellular and humoral responses of Brucella abortus-infected bovine fetuses
Authors: Enright F. M. , Walker J. V. , Jeffers G. , Deyoe B. L.
Published: February 2025

Fifty-nine bovine fetuses naturally and experimentally infected with Brucella abortus were studied. Lymphoid hyperplasia in multiple lymph nodes, lymphoid depletion in the thymic cortex, adrenal cortical hyperplasia, and disseminated inflammatory foci composed mainly of large mononuclear leukocytes were present in infected fetuses. Histopathologic changes in naturally infected fetuses were indistinguishable from those infected fetuses inoculated in utero. Fetuses inoculated with 1.0 × 103 to 1.0 × 105 colony-forming units of strain 2308 B abortus were aborted on postinoculation day (pid) 7 to 19. Fetuses obtained by pid 9 and 10 had increased immunoglobulin concentrations and antibody. Increased cortisol values were present in fetuses obtained as early as pid 6. The initial fetal inflammatory response was composed of large mononuclear leukocytes. In fetuses obtained by pid 9 to 10, moderate numbers of neutrophils mixed with mononuclear leukocytes were present in the inflammatory foci. This shift in the initial inflammatory reaction coincided with the appearance of agglutinating antibody.
Development and characterization of a hybridoma-derived antibody (Aby 1A1) with specificity to canine thymocytes and peripheral T lymphocytes
Authors: Krawiec Donald R. , Muscoplat Charles C.
Published: February 2025

A hybridoma (1A1)-producing antibody with reactivity to canine T-lymphocyte surface antigens was produced, using standard fusion techniques. Antibody secreted from this hybridoma was tested for specific anti-canine lymphocyte activity, using an enzyme-linked immunosorbent assay, an indirect-fluorescent antibody assay, and cytotoxicity assay. Antibody 1A1 reacted with canine T lymphocytes, but not with B lymphocytes, and with brain tissue and connective tissue. The antibody was also characterized. Its heavy chain had a molecular weight (mol wt) of 80,000 and its light chain was 28,000 mol wt. The Aby 1A1 is a monoclonal immunoglobulin M with a κ light chain, and it binds poorly to Staphylococcus A.
Development and characterization of a monoclonal antibody (Aby 6C6) that distinguishes medullary from cortical thymocytes
Authors: Krawiec Donald R. , Muscoplat Charles C.
Published: February 2025

A hybridoma (6C6) producing antibodies with specificities to canine thymocyte surface antigens was produced using standard fusion techniques. The Aby 6C6 has affinity for medullary thymocytes, bone marrow cells, T- and B-peripheral lymphocytes, and monocytes. The Aby 6C6 appears to have 2 heavy chains with different molecular weights, an isoelectric focusing pattern consistent with monoclonality, and is an immunoglobulin G2b antibody with a κ light chain.
Influence of reduced protein diets on morbidity, mortality, and renal function in dogs with induced chronic renal failure
Authors: Polzin David J. , Osborne Carl A. , Hayden David W. , Stevens Jerry B.
Published: February 2025

The influence of a maintenance diet containing 44.4% dry weight protein and 2 reduced protein diets containing 8.2% and 17.2% dry weight protein on morbidity, mortality, and renal function of dogs with induced chronic renal failure was studied for 40 weeks. The diets differed in mineral and electrolyte composition in addition to differences in protein, carbohydrate, and fat content. Dogs fed the 44.4% protein diet had a higher mortality (6 of 11) than did dogs fed the 8.2% (1 of 6) or 17.2% (0 of 6) protein diets. Dogs fed the 44.4% protein diet died of uremic complications. An occlusive portal vein thrombus caused death of the nonsurvivor fed the 8.2% protein diet. Clinical signs of uremia were detected only in nonsurvivors fed the 44.4% protein diet. Surviving dogs fed the maintenance diet were less active and had poorer hair than did dogs fed reduced protein diets.

Inulin clearance rate and urinary protein excretion were lower in most dogs fed reduced protein diets than in dogs fed the maintenance diet. Despite the greater decrease in renal function, serum urea nitrogen concentrations were markedly lower in dogs fed the 8.2% and 17.2% protein diets than in dogs fed the 44.4% protein diet. Seemingly, the reduced protein renal failure diets were of benefit in preventing or reducing morbidity and mortality associated with the uremic syndrome and in reducing serum urea nitrogen concentrations as compared with that of the higher protein diet. The potential benefits of dietary protein restriction in dogs with chronic renal failure prevailed over potential adverse affects of excessive protein consumption.
Effects of Onthophagus gazella F (Coleoptera: Scarabaeidae) on free-living strongyloids of equids
Authors: Houston R. S. , Craig T. M. , Fincher G. T.
Published: February 2025

Effects on the recently introduced dung-burying beetle, Onthophagus gazella F, on free-living stages of equine strongyles were determined on a Texas pasture. Two populations of O gazella (22 and 44 pairs) were exposed to 1-kg deposits of equine dung containing 545,000 strongyle eggs for 31 days near the end of the beetle’s activity season. Weekly dung and pasture samples were taken from these plots and from control plots from which beetles were excluded to recover developing larvae. Significant differences did not occur among the 3 treatments (P < 0.05).
Chloramphenicol sodium succinate in the horse: Serum, synovial, peritoneal, and urine concentrations after single-dose intravenous administration
Authors: Brown Murray P. , Kelly Robin H. , Gronwall Ronald R. , Stover Susan M.
Published: February 2025

Six healthy adult mares were given a single iv dose (25 mg/kg of body weight) of chloramphenicol sodium succinate. Chloramphenicol concentrations in serum, synovial fluid, peritoneal fluid, and urine were measured serially over a 48-hour period. The highest measured serum chloramphenicol concentration was 6.21 μg/ml at 0.5 hour. Chloramphenicol was detected in synovial and peritoneal fluids, with mean peak concentrations of 3.89 μg/ml and 3.50 μg/ml, respectively, at 0.5 hour. Serum and synovial concentrations declined rapidly and were not measurable at 3 hours. Chloramphenicol could not be detected in peritoneal fluid at 6 hours. The serum half-life was 0.43 hour and the apparent volume of distribution was 2.83 L/kg. Urine concentrations of chloramphenicol peaked at 0.5 hour at 106.72 μg/ml and also declined rapidly. The drug could not be detected in the urine at 36 hours.
Effects of halothane anesthesia on equine liver function
Authors: Engelking Larry R. , Dodman Nicholas H. , Hartman Gail , Valdez Henry , Spivak William
Published: February 2025

SUMMARY AND CONCLUSIONS

Effects of halothane anesthesia were investigated in ponies prepared surgically with chronic external biliary fistulas (T tubes) to determine the effects on liver function and biliary excretion during 2 hours of anesthesia. Four studies were performed on 2 ponies, 2 to 6 months after surgery with the enterohepatic circulation held intact between studies. Intravenous bile acid infusion was used to maintain steady-state bile flow, bilirubin, and bile acid excretion during each study. Compared with the immediate 2-hour preanesthesia values (base line), halothane caused a 138% increase in bilirubin excretion, a 60% increase in biliary bilirubin concentration, and a 43% increase in pcv. Halothane anesthesia also caused a 16% reduction in plasma bilirubin, a 46% reduction in biliary bile acid concentration, and a 27% reduction in bile acid excretion. The bile acid independent fraction of bile flow appeared to increase. Plasma aspartate transaminase concentration did not change during anesthesia.

The ratio of conjugated bilirubin fractions in bile [82% to 83% diconjugates of glucuronide and glucoside (2 forms) and 17% to 18% monoconjugates of glucoside, glucuronide, and xyloside] did not change during anesthesia and < 1% was excreted unconjugated. Halothane anesthesia did not appear to affect adversely the activity of the transferase-conjugating enzymes in the presence of an increased bilirubin load.

Seemingly, greatly increased conjugated bilirubin excretion observed during halothane anesthesia was most likely the result of a combination of increased hepatic clearance from plasma and increased hepatic bilirubin production from turnover of free hepatic heme or heme from the induced cytochrome P-450 system. The reduction in bile acid excretion may result potentially from a decrease in hepatic blood flow. Halothane anesthesia does not appear to disrupt hepatic parenchymal cells in the pony; however, it does reduce bile acid excretion and enhance pcv, bile acid-independent bile flow, and conjugated bilirubin excretion.
Radiographic, macroscopic, and microscopic changes in growth plates of calves raised on hard flooring
Authors: White Susan L. , Rowland George N. , Whitlock Robert H.
Published: February 2025

The effect of flooring on the development of physeal and metaphyseal lesions of the limbs was studied in 1- to 5-month-old dairy calves. Calves were allotted to 2 groups. Group I was housed on a clay floor throughout the study and group II was housed on metal slats until weaned and then on concrete. Radiographs of the right thoracic limb of the animals were made 7 times during the experimental period and of the right thoracic and pelvic limbs at necropsy. Selected sections of the physeal regions of the distal part of the radius, metacarpus, metatarsus, and rib were examined microscopically. The physes of the limbs in the 2 groups had eosinophilic streaks and patches which originated in the germinal zone and were associated with blood vessels. These foci varied from small streaks parallel to the chondrocyte columns to multiple horizontal branching patches in which cleft formation and necrosis interrupted the physis, resulting in osseous bridging. Remnants of necrotic cartilage or cartilage containing hypertrophied chondrocytes were located in the metaphysis adjacent to the areas of physeal disruption. Multiple undulations of the physes with variations in thickness and orientation of the chondrocyte columns occurred in the physes of all limbs examined. These areas did not interrupt the physis and were not associated with metaphyseal lesions. The ribs in both groups had focal areas of failure of endochondral ossification characterized by elongation of the hypertrophied zone, accumulation of fibrin and hemorrhage in the zone of provisional calcification, and retention of cartilage within the metaphysis. The distribution of lesions within individual calves and the morphologic character of the lesions were consistent with the changes described for osteochondrosis. The tendency for more severe and more numerous lesions in group II indicates that the hard flooring may exacerbate the lesions of osteochondrosis.
Effect of combined rotavirus and Escherichia coli in neonatal gnotobiotic calves
Authors: Torres-Medina Alfonso
Published: February 2025

Gnotobiotic calves (24 hours old) were monoinfected with calf rotavirus (crv) strain NCDV, an enterotoxigenic Escherichia coli (etec) strain B44 (K99 + ), or a nonenterotoxigenic Ε coli (netec) strain 123 (K99-). Calves also were dually infected with crv and either etec or netec. Eighteen calves equally allotted between 6 treatment groups were used in these studies: Noninfected controls—group A; crv—group B; etec—group C; netec-—group D; crv + etec—group E; and crv + netec—group F. Severe diarrhea and villous atrophy were observed in calves of treatment groups B, C, E, and F. Mortality was present only in treatment groups C and Ε as result of etec infection. There were no significant deferences in the clinical responses or enteric lesions between treatments B and F, although a significant increase in the concentrations of netec was demonstrated in calves dually infected with crv + netec (group F) as compared with calves monoinfected with netec (group D). Calves inoculated with etec (group C) had severe villous atrophy, neutrophilic infiltration of intestinal lumen, and moderate enterocyte necrosis. Calves dually inoculated with crv + etec (group E) had the most extensive and severe lesions, similar to those in group C, plus a pronounced necrotic fibrino-hemorrhagic enteritis. Infection of enterocytes by crv did not affect in any way the adherence of etec to the intestinal mucosa. Dual viral and bacterial infections of the same enterocytes were evident.
Effect of rotavirus and/or Escherichia coli infection on the aggregated lymphoid follicles in the small intestine of neonatal gnotobiotic calves
Authors: Torres-Medina Alfonso
Published: February 2025

The effect of rotavirus and/or Escherichia coli infections on the follicle-associated epithelium (fae or M cells) of the domes of the aggregated lymphoid follicles (alf, or Peyer's patches) of gnotobiotic calves was evaluated by light, scanning electron, transmission electron, and immunofluorescence microscopies. Calf rotavirus (crv) infection produced loss of fae cell microvilli, and virions were observed in cytoplasmic vacuoles of fae cells, as well as in intercellular spaces between fae cells and lymphoid cells migrating through the dome epithelium. The crv particles appeared to have entered the fae cells by phagocytosis, with no subsequent cytoplasmic replication. Enterotoxigenic Ε coli (etec) induced more severe alterations including marked microvilli loss and ballooning in the fae cells. There was no adhesion to, or colonization of fae cells by etec, but bacteria were observed free or phagocytized within the dome and the germinal centers of the alf. There were no etec observed in the cytoplasm of fae cells. The presence of nonenterotoxigenic Ε coli (netec) in the intestine of calves had no effect on the intestinal fae cells. The addition of netec to crv infections did not enhance or modify in any way the response of fae cells to the viral infection; however, the combination of crv + etec produced severe necrosis of the fae cells, and loss of dome epithelium of alf.
Effects of Escherichia coli endotoxin on leukocyte and platelet counts, fibrinogen concentrations, and blood clotting in colostrum-fed and colostrum-deficient neonatal calves
Authors: Deldar A. , Naylor J. M. , Bloom J. C.
Published: February 2025

Effects of a single iv injection of Escherichia coli endotoxin on hemogram and clotting function were compared in colostrum-fed and colostrum-deficient neonatal calves. Before endotoxin administration, the 2 groups of calves only differed in their prothrombin times. After endotoxin administration, there were significant differences (P < 0.005) between colostrum-fed and colostrum-deficient calves in total leukocyte, segmented neutrophil, nonsegmented neutrophil, and lymphocyte (P < 0.05) counts and partial thromboplastin time. Significant time dependent changes were observed in the aforementioned parameters and in platelet count and fibrinogen concentration.

Seemingly, colostrum feeding improved the calf's ability to respond to endotoxin challenge exposure probably because of improved granulopoietic activity.
Effect of bovine viral diarrhea virus infection on the distribution of infectious bovine rhinotracheitis virus in calves
Authors: Potgieter L. N. D. , McCracken M. D. , Hopkins F. M. , Walker R. D.
Published: February 2025

Four calves (control animals) were inoculated (by aerosol) with Cooper's strain of infectious bovine rhinotracheitis (ibr) virus given with an ultrasonic nebulizer. Seven other calves (principals) were inoculated (by aerosol) with a noncytopathic strain of bovine viral diarrhea (bvd) virus and 7 days later, with ibr virus. The calves were killed 3 to 8 days after the latter virus was inoculated. Various tissues were collected from the calves during necropsy and assayed for ibr virus.

In the control calves, the ibr virus was recovered only from the cranial part of the respiratory tract and, in much lower concentrations, from the caudal part of the respiratory tract. In contrast, the same virus was widely disseminated in most tissues, usually in high concentrations, of the calves first inoculated with bvd virus (principals). These observations indicate that initial bvd virus infection may impair the ability of calves to clear ibr virus from the lungs and to contain the latter virus at the local infection site. The pathogenesis of various forms of ibr virus-induced diseases in calves is discussed.
Peripheral distribution of virus in dogs inoculated with two strains of rabies virus
Authors: Fekadu Makonnen , Shaddock John H.
Published: February 2025

Forty-seven Beagles were inoculated im with an Ethiopian strain or a Mexican strain of rabies virus to study the pathogenesis of street rabies virus in dogs. Thirty-nine dogs died of rabies, with incubation periods lasting 9 to 69 days. Of the dogs that died, 82% had shown typical signs of rabies, but 18% died without any noticeable signs of illness. Eight dogs that remained healthy during an observation period lasting more than 2 years did not produce detectable amounts of rabies virus-neutralizing antibodies; however, when challenge exposed with a large dose of the homologous rabies virus inoculum, these 8 dogs responded with high antibody titers, but challenge-exposed control dogs died of rabies.

Infective virus was isolated from the saliva and cerebrospinal fluid of dogs before any signs of rabies were noticed; rabies virus-neutralizing antibodies were not detected in the serum and cerebrospinal fluid before illness. In this study, viral antigen was not detected in the skin biopsy specimens taken before signs of rabies were noticed. At necropsy of the 39 dogs, rabies virus was detected in most tissues examined.

Viral antigen was detected in the skin tissues of 14 (36.8%) of the 38 dogs examined. The presence of viral antigen in the skin seemed to correlate with the presence of virus in the salivary glands, but virus in the salivary glands did not indicate the presence of virus in the skin. Eleven (44%) of the 25 dogs which had virus in the salivary glands did not have any detectable amount of viral antigen in the skin. The distribution of virus seemed to depend on the dose of inoculum and the strains used.
Lipopolysaccharides of the Heddleston serotypes of Pasteurella multocida
Authors: Rimler R. B. , Rebers P. A. , Phillips M.
Published: February 2025

Lipopolysaccharides (lps) were extracted from 13 of the 16 Heddleston serotypes of Pasteurella multocida by phenol-chloroform-petroleum ether (pcp). Serotypes 3, 9, and 13 were extracted only by phenol-water (pw). After extraction of lps of serotype 9 by pw, an additional lps was isolated by pcp. All lps contained glucose, 2-keto-3-deoxyoctonate, and heptose. Two isomers of heptose, d-glycero-d-mannoheptose and l-glycero-d-mannoheptose, were found in serotypes 2 and 5. Antisera made against purified lps of serotypes 2 and 5 reacted with both heat-stable antigens and lps from serotypes 2 and 5 in the gel-diffusion precipitin test. Antisera against serotype 2 lps protected turkeys against challenge with capsulated serotype 5, indicating that a structural relationship exists between lps of strains that cause hemorrhagic septicemia and fowl cholera.

Rhamnose was a component of serotype 9 lps, and galactose was found in all lps, except for serotype 11. The lps of serotype 13 contained an isomer of heptose that has not been identified.

The lps had buoyant densities in CsCl of 1.40 ± 0.0148 g/ml, and all hemagglutinated chicken and turkey, but not sheep or horse, rbc.
Control of Boophilus ticks on heifers with two pyrethroids applied as sprays
Authors: Davey R. B. , Ahrens Ε. H.
Published: February 2025

The pyrethroid permethrin (25% cis to 75% trans) was sprayed on Hereford heifers infested with all parasitic stages of Boophilus microplus (Canestrini) at 0.05% and 0.1% active ingredient. At 0.05%, control was 66.7%; whereas at 0.1%, control was 93.3%. Replete females were collected daily for 28 days after treatment at both concentrations, indicating that at least some ticks treated as larvae or nymphs were able to reach repletion.

The pyrethroid fenvalerate was sprayed on Hereford heifers infested with all parasitic stages of B microplus or B annulatus (Say) at 0.025% and 0.05% active ingredient. Fenvalerate was as effective as permethrin at a lower concentration. At 0.025%, control was 89.2% and 86.6% and at 0.05% was 92.5% and 90.1% for B microplus and B annulatus, respectively.

Both these pyrethroids could provide adequate reduction in programs in which control is the aim; however, in an eradication program, both acaricides failed to provide the necessary reduction to achieve complete elimination.
Uterotonic effect of prostaglandin F2α and oxytocin on the postpartum cow
Authors: Eiler Hugo , Hopkins Fred M. , Armstrong-Backus Cindy S. , Lyke Wilfred A.
Published: February 2025

Uterine motility was measured in 6 mixed-breed beef cows 48 to 72 hours after parturition, using an intrauterine balloon technique. Baseline uterine motility was measured for 30 minutes after a stabilization period. After 25 mg of prostaglandin F2α, (pgf2α) was given im, motility was recorded for 2 to 4 hours. After pgf2α injection, 200 IU of oxytocin was given im and motility was recorded for 2 to 4 hours.

Twenty-four hours later, oxytocin treatment was administered, and 2 to 4 hours later, pgf2α was given. The tension-time index was calculated.

When pgf2α was given initially, it did not affect (P > 0.05) uterine motility. However, oxytocin after pgf2α increased uterine motility an average of about 225% of that of base line 20 minutes after injection. When oxytocin was given before pgf2αtreatment, the average increment of uterine motility was 875% above base line 20 minutes after oxytocin injection. The injection of pgf2α did not affect uterine motility significantly (P > 0.05), whether given before or after oxytocin treatment. There was a linear decrease in the uterotonic effect of oxytocin between 10 minutes and 2 hours. When oxytocin was injected first, the correlation coefficient for the time-response relationship was −0.98. When oxytocin was injected after pgf2α, the correlation coefficient was −0.84.

Seemingly, pgf2α should not be used as a uterotonic agent in the postpartum cow; however, oxytocin was an effective uterotonic agent.
Morphologic, cytochemical, and functional studies of peripheral blood cells of young healthy American alligators (Alligator mississippiensis)
Authors: Mateo M. R. , Roberts E. D. , Enright F. M.
Published: February 2025

Samples of peripheral blood collected from healthy young American alligators (Alligator mississippiensis) were studied to determine baseline values and characterize cell types. Mean total leukocyte counts were 6.4 ± 2.9 × 103/mm3, with mean differential values of 54.7 ± 47.5% heterophils, 10.4 ± 6.0% eosinophils, 12.7 ± 16.8% basophils, 23.9 ± 4.9% lymphocytes, and 0.7 ± 0.5% monocytes. Mean total thrombocyte counts were 23.0 ± 7.0 × 103/mm3, and mean total erythrocyte counts were 3.84 ± 8.7 × 105/mm3. Morphologic descriptions of Wright-Giemsa-stained alligator blood cells generally corresponded to those of their counterparts in other reptiles, birds, and mammals. Cytochemical tests were positive as follows: chloroacetate esterase-lymphocytes and monocytes; nonspecific esterase-heterophils and monocytes; acid phosphatase-heterophils, basophils, and monocytes; and alkaline phosphatase-heterophils, eosinophils, and monocytes. Phagocytic and microbiocidal capacity was tested by adding live Staphylococcus aureus to whole blood. Subsequent staining with acridine orange and observation with fluorescence microscopy showed in vitro phagocytic and microbiocidal activity of monocytes, heterophils, and to a lesser degree, eosinophils.
Experimentally induced Cooperia oncophora infection in calves: Lymphocyte blastogenic and delayed hypersensitivity responses
Authors: Hanrahan L. A. , Benz G. W. , Schultz R. D.
Published: February 2025

Lymphocytic responses in peripheral blood and visceral lymph to Cooperia oncophora antigen and skin tests were determined in 35 Holstein male calves that were inoculated orally with single or multiple doses of C oncophora infective larvae. Several calves were vaccinated or given immune serum before larvae were inoculated. Antigen-specific in vitro blastogenesis of blood and lymph lymphocytes and delayed-type hypersensitivity reactions were observed in several inoculated, vaccinated, and/or passively immunized calves. Most calves that had delayed skin reactions also had in vitro lymphocyte responses to C oncophora antigen. The lymphocyte and skin responses were inconsistent and variable in time of onset—the earliest lymphocyte response occurring 7 days after calves were inoculated. A cellular immune response was induced by both dermal vaccination and oral inoculation however, passive immunization by iv administration of immune serum simultaneously with inoculation did not have an apparent effect on the cellular response, as measured by the lymphocyte blastogenesis test or dermal testing. Although cellular immune responses were observed in several calves infected with C oncophora, there was no apparent relationship between the specific responses and number of nematodes establishing infection in calves after either single- or multiple-dose oral inoculations.
Functional anatomy of the equine tarsocrural collateral ligaments
Authors: Updike Susan J.
Published: February 2025

Equine tarsocrural collateral ligaments (cl were dissected grossly. The areas of attachment and fiber arrangements were described for the long lateral cl, long medial cl, 3 short lateral cl, and 3 short medial cl. Sequential cutting of cl in any order indicated that the short medial cl were responsible for the snap-joint phenomenon observed at the equine tarsocrural joint.
Stride characteristics of horses competing in Grand Prix jumping
Authors: Leach D. H. , Ormrod K. , Clayton H. M.
Published: February 2025

An investigation was made of the stride characteristics of horses jumping 2 obstacles during a Grand Prix competition. One obstacle was a picket fence and rail 1.3 m high (fence 2), and the other was a coop and rail 1.52 m high (fence 11). Thirteen distance and 22 timing measurements of 17 horses were extracted from high-speed films, using computer-aided analysis. These data were used to compare takeoff and landing of the lead and nonlead legs, the thoracic limbs and pelvic limbs, and fence 2 and fence 11. Paired t-tests were used to compare means and a stepwise regression analysis was done for each fence, using the total horizontal distance jumped as the dependent variable.

Stride timing and distance measurements did not differ (P < 0.05) between the 2 fences. Each horse approached the fences in a moderately fast canter and, at takeoff, placed the nonlead thoracic limb earlier and farther from the fence than the lead thoracic limb (P < 0.05). The nonlead leg stance phase lasted longer than the lead leg stance phase (P < 0.05). The lead and nonlead pelvic limbs acted more in unison than the thoracic limbs and did not differ in their time of placement, stance phase duration, or position from the fence (P < 0.05). The overlap of the stance phases of the pelvic limbs was greater than that of the thoracic limbs (P < 0.05). The pelvic limbs remained on the ground for a longer period of time and were placed closer to the jump than the thoracic limbs (P < 0.05), but the total stance phase of the thoracic limbs did not differ from the total stance phase of the pelvic limbs (P < 0.05).

In 15 of 29 jumps studied, the lead thoracic limb changed during the jump. In the landing phase the lead thoracic limb was positioned further from the jump and had a longer stance phase and single support than did the nonlead thoracic limb (P < 0.05). The overlap increased and advanced placement decreased between these limb pairs on landing as compared with the takeoff (P < 0.05). The distance between the pelvic limbs at landing was greater than at takeoff (P < 0.05), but was not significantly different from the distance between the thoracic limbs at landing.

The stepwise regression analysis selected different independent variables for the 2 fences. The final regression equation for fence 2 included 5 independent variables and had an adjusted R2 value of 0.999. Four of these independent variables were distance measurements and 4 described the thoracic limbs. The R2 value of the final regression equation for fence 11 was 0.953 and all 3 independent variables selected were distance measurements of the pelvic limbs.
Cellular constituents of clinically normal foal bronchoalveolar lavage fluid during postnatal maturation
Authors: Zink M. C. , Johnson J. A.
Published: February 2025

Bronchoalveolar lavage was performed 5 times, sequentially, on 3 healthy foals when each was between 2 and 63 days of age. Total and differential counts were performed on recovered cells. The lungs of foals < 19 days of age contained few alveolar macrophages recoverable by bronchoalveolar lavage. This number increased sharply during the first 2 to 3 weeks of life, but remained relatively constant subsequently. Approximately 86% of the alveolar cells in the lungs of foals up to 3 weeks of age were alveolar macrophages. During the first 2 months of life, this number decreased to approximately 71%, whereas the relative percentage of lymphocytes increased from 5% to 20%.