bluuebunny/crossref_metadata_2025_split huggingface dataset:
Effect of xylazine in heifers under thermoneutral or heat stress conditions
Authors: Fayed A. H. , Abdalla E. B. , Anderson R. R. , Spencer K. , Johnson H. D. 
Published: February 2025

SUMMARY
A study was performed to assess the effect of xylazine HCl (0.1 mg/kg of body weight, IV) in heifers maintained at thermoneutrality (18 C, 42% humidity) or under heat stress (33 C, 63% humidity) conditions. Xylazine caused 50 and 70% decreases in serum insulin concentrations in the thermoneutral and heat-stressed heifers, respectively. Xylazine-induced hypoinsulinemia was associated with hyperglycemia. In the thermoneutral group, serum glucose concentrations increased from a basal concentration of 75 mg/dl to 150 mg/dl after 15 minutes. In the heat stress group, the serum glucose concentration increased from 65 mg/dl to 105 mg/dl. Hyperglycemia peaked at 2 hours and remained high for 6 hours after xylazine administration. Heat-stressed heifers took a longer time (107 minutes) to stand than did heifers under thermoneutral conditions (41 minutes). The time to regain sensation to pain was significantly prolonged in heat-stressed heifers. Xylazine had no effect on body temperature and respiration rate in heifers under the thermoneutral condition, whereas it markedly induced hyperthermia and suppressed respiration rate in the heat-stressed heifers. Furthermore, the pulse rate was slightly decreased in thermoneutral heifers and was markedly decreased in the heat-stressed heifers.
Onchocerca gutturosa and Onchocerca lienalis in cattle: Variation in length of microfilariae by site of recovery
Authors: Harty T. M. , Ferenc S. A. , Copeman D. B. , Courtney C. H. 
Published: February 2025

SUMMARY
Dermal microfilariae recovered from specimens obtained from umbilical and cervical sites of cattle infected with adult Onchocerca gutturosa alone or with adults of O gutturosa and O lienalis were measured and compared with uterine microfilariae obtained directly from gravid female worms of each species.
Uterine microfilariae of O gutturosa were longer than dermal microfilariae obtained from cattle harboring only adults of O gutturosa. Dermal microfilariae were recovered from umbilical and cervical sites in these cattle. Those found at the cervical site had lengths equal to or greater than lengths of microfilariae recovered from the umbilical site. There was a significant (P < 0.0001) shift in length across populations of microfilariae of O gutturosa from various sites in its bovine host, with a progressive decrease in length between microfilariae recovered from the worm's uterus, microfilariae from the cervical dermis, and microfilariae from the umbilical dermis, respectively. A similar direct comparison was not possible for microfilariae of O lienalis, because none of the cattle was infected with only adult worms of this species. In an indirect comparison, microfilariae of O lienalis were identified at the umbilicus, but their presence in the cervical region could not be determined unequivocally because of confounding of microfilariae length by concurrent infection with O gutturosa. Uterine microfilariae from O lienalis were longer than uterine microfilariae of O gutturosa, although a degree of overlap in the range of measurements existed between species.
Serum relaxin and progesterone concentrations in pregnant, pseudopregnant, and ovariectomized, progestin-treated pregnant bitches: Detection of relaxin as a marker of pregnancy
Authors: Steinetz Bernard G. , Goldsmith Laura T. , Harvey H. Jay , Lust George 
Published: February 2025

SUMMARY
Serum concentrations of relaxin and progesterone were measured by specific radioimmunoassays in pregnant, pseudopregnant, or ovariectomized (between gestation weeks 4 and 5) pregnant Labrador Retriever bitches. Daily administration of 17α -ethyl - 19 - nortestosterone was performed to maintain gestation in the ovariectomized pregnant bitches. This synthetic gestagen was selected because it did not interfere with the assay for endogenously secreted progesterone concentration in serum.
Serum progesterone concentration was high in ovarianintact pregnant or pseudopregnant bitches, but the mean progesterone concentration in pseudopregnant bitches (evaluated at 4 weeks after mating) was only 56% of the concentration in pregnant bitches. After ovariectomy, serum progesterone concentration decreased to undetectable values. Unlike progesterone, serum relaxin concentration increased during the latter half of pregnancy in the ovarian-intact and in the ovariectomized pregnant bitches, but relaxin was not detectable at any time in the pseudopregnant bitches.
The amount of relaxin pregnant measured in the ovariectomized pregnant bitches was less (P < 0.05) than that in overianintact bitches, suggesting that the ovaries may have contributed to the total circulating relaxin concentration in the latter. Placental production of relaxin might have accounted for the serum relaxin concentration after ovariectomy; thus, the ovary and placenta each may secrete relaxin during gestation in bitches.
Regardless of its source, measurement of serum relaxin concentration may offer a useful way of distinction between pregnancy and pseudopregnancy in dogs.
Increased peroxidation of erythrocytes of stress-susceptible pigs: An improved diagnostic test for porcine stress syndrome
Authors: Duthie Garry G. , Arthur John R. , Bremner Patricia , Kikuchi Yuji , Nicol Fergus 
Published: February 2025

SUMMARY
When incubated with solutions of hydrogen peroxide, erythrocytes of stress-susceptible pigs produced more by-products of lipid peroxidation (as measured as thiobarbituric acid-reactive substances [tbars]) than did erythrocytes from stress-resistant pigs. Using this technique, discrimination between the 2 pig types was absolute at hydrogen peroxide concentrations of 0.9 and 1.5%. This was in contrast to other methods of identifying stress-susceptible pigs, such as osmotically induced erythrocyte lysis and the determination of plasma pyruvate kinase and creatine kinase activities, for which considerable overlap of data was observed between pig types. The increased tbars production by erythrocytes was further evidence for the existence of an antioxidant abnormality in stress-susceptible pigs. However, because there were no discernible differences in the major blood antioxidant-related values between stress-susceptible and stress-resistant pigs, the nature of the defect remains unclear. The production of tbars by erythrocytes when incubated with hydrogen peroxide provides an improved method for identifying stress-susceptible pigs.
Echocardiographic assessment of cardiac chamber size and functional performance in swine
Authors: Gwathmey Judith K. , Nakao Shoichiro , Come Patricia C. , Abelmann Walter H. 
Published: February 2025

SUMMARY
Ninety nonanesthetized 7- to 16-week-old pigs were studied, using 2-dimensional echocardiography that permits orientation of a targeted M-mode beam perpendicular to structures being studied and allows serial studies of the same cardiac regions. Normative data were obtained and included body weight and measurements of left atrial diameter, mitral valve excursion, aortic root diameter, left ventricular end-diastolic and end-systolic diameters, and left ventricular fractional shortening. A positive correlation was found between body weight and measurements of left atrial diameter, mitral valve excursion, aortic root diameter, left ventricular end-diastolic and end-syatolic diameters, and fractional shortening. A correlation was found between body weight and age. Best-fit analysis resulted in all measurements fitting either a first- or second-degree polynomial.
Detection of turkey enteric coronavirus by enzyme-linked immunosorbent assay and differentiation from other coronaviruses
Authors: Dea Serge , Tijssen Peter 
Published: February 2025

SUMMARY
A double-antibody ELISA for the detection of coronaviruses in intestinal contents from turkey poults with diarrhea was developed. Antibodies were raised in rabbits and guinea pigs against a Minnesota isolate of turkey enteric coronavirus (TCV) propagated in embryonating turkey eggs and were purified by density-gradient centrifugation. The specificity of antisera was confirmed by hemagglutination-inhibition and immunoelectron microscopy. Absorption of anti-TCV hyperimmune sera with egg extracts or egg ovalbumin and the use of different dilution and blocking buffers influenced the sensitivity and specificity of the ELISA. Reciprocal cross-reactivity was detected among turkey, chicken, bovine, and murine coronaviruses. Antisera to the transmissible gastroenteritis virus of swine, the rabbit enteric coronavirus, or the human coronavirus strain 299E failed to react with TCV. The TCV cross-reacted only moderately with the avian infectious bronchitis virus and the hemagglutinating en-cephalomyelitis virus of swine. Investigations with samples from 47 commercial turkey flocks in Quebec with episodes of transmissible enteritis revealed that the ELISA was more sensitive than was electron microscopy for detection of TCV.
Influence of dietary source of phosphorus on fecal and urinary excretion of phosphorus and other minerals by male cats
Authors: Finco Delmar R. , Barsanti Jeanne A. , Brown Scott A. 
Published: February 2025

SUMMARY
Twelve male cats were fed 2 diets that differed in the source of P. In diet 1 (14% P), 62.7% of P originated from poultry, meat, and fish meal, and the remainder from other organic ingredients of food. In diet 6 (1.6% P), 63.5% of P was derived from neutral monobasic/dibasic salts, and the remainder from other organic ingredients of the food.
The P intake was nearly the same with both diets, but there was a significant (P < 0.05) difference between diets in the percentage of ingested P that was excreted in the urine (14.7 ± 5.3% for diet 1; 34.9 ± 8.4% for diet 2), and in 6-day urinary P excretion (774 ± 290 mg for diet 1; 2,004 ± 556 mg for diet 2). The P concentrations in urine samples obtained by cystocentesis after cats ate were significantly (P < 0.05) higher when cats were fed diet 2 than when those same cats were fed diet 1. Plasma P concentrations increased after ingestion of diet 2, but were unchanged after ingestion of diet 1. Seemingly, urinary excretion of P was markedly influenced by dietary composition. Diets with the same P content have potential for different biologic effects because of differences m availability of P.
Effects of Pasteurella haemolytica leukotoxin on cultured bovine lymphoma cells
Authors: Clinkenbeard Kenneth D. , Mosier Derek A. , Timko Andrea L. , Confer Anthony W. 
Published: February 2025

SUMMARY
Leukotoxin activity from culture supernatants of Pasteurella, haemolytion serotype 1 in logarithmic growth phase caused rapid « 5 min) release of intracellular K+, uptake of extracellular Ca2+, and swelling of cultured bovine lymphoma cells (BL3 cells). Release of 51CrO42- and lactate dehydrogenase (LDH) from BL3 cells began after 15 minutes of incubation with leukotoxin at 37 C and was completed between 60 and 120 minutes of incubation. In addition, leukotoxin exposure of BL3 cells resulted in cell aggregation and adherence to glass surfaces. Scanning electron microscopy indicated that after 10 minutes of leukotoxin exposure, BL3 cells increased in size, and large membrane defects developed between 20 and 60 minutes of exposure. The rate of release of LDH from leukotoxin- exposed BL3 cells was proportional to the amount of leukotoxin added. At high cell concentrations, the activity of LDH released at completion was directly proportional to the amount of leukotoxin added. Leukotoxin-induced release of LDH required a divalent cation, whereas K+ release and cell swelling did not. The addition of Ca2+, Mn2+, and Ba2+ resulted in increased leukotoxin-induced release of LDH. Divalent cation concentrations of 0.5 to 2.5 mM resulted in 50% of maximal stimulation. Ethylene glycol-bis(ß-aminoethyl ether) N,N,N’,N’-tetraacetic acid blocked increased release of LDH caused by Ca2+ addition, but had no effect on K+ release or cell swelling. Leukotoxin action on BL 3 cells (K+ release, cell swelling, Ca2+ uptake, and release of LDH) was prevented by incubation at 4 C.
Cardiopulmonary changes in conscious dogs with induced progressive pneumothorax
Authors: Bennett R. Avery , Orton E. Christopher , Tucker Alan , Heiller Cynthia L. 
Published: February 2025

SUMMARY
Cardiopulmonary function was measured in 6 conscious dogs with progressive degrees of induced pneumothorax. Minute volume, respiratory rate, central venous pressure, systemic arterial pressure, pulmonary arterial pressure, pulmonaiy arterial occlusion pressure, heart rate, cardiac output, and arterial and mixed venous blood gases were determined before pneumothorax and at progressive volumes of pneumothorax equivalent to 50, 100, and 150% of the calculated lung volume. Tidal volume, pulmonary vascular resistance, alveolar to arterial O2 tension difference, physiologic dead space fraction, and pulmonary venous admixture also were calculated.
Linear increases in respiratory rate, central venous pressure, alveolar to arterial O2 tension difference, and pulmonary venous admixture differed significantly (P < 0.05). Linear decreases in tidal volume, pHv̄, pHa, Pv̄O2, and PaO2 were also significantly different. Quadratic increases were significantly different for pulmonary arterial pressure and pulmonary vascular resistance. Trends were not significantly different for other values.
Influence of major histocompatibility genes on serum hemolytic complement activity in miniature swine
Authors: Mallard B. A. , Wilkie B. N. , Kennedy B. W. 
Published: February 2025

SUMMARY
Total serum hemolytic complement (CH50) activity was determined for 3 semi-inbred strains of miniature swine (SLAa, SLAc, and SLAd) and 1 recombinant strain SLAg (ABCcDd), each homozygous for a distinct major histocompatibility complex haplotype. Initial determination was made at 8 weeks of age, prior to standardized immunization, the second at age 12 weeks, after immunization. Analysis of variance was by least-squares method, using a linear model on data from 33 litters by 14 sires and 16 dams. Analysis of variance indicated that the combined effects of haplotype, sire, dam, litter, and gender accounted for 47.63% of the total variation in preimmunization CH50 values. Dam (P ≤ 0.06) and litter (P ≤ 0.03) significantly influenced preimmunization complement activity. Although swine leukocyte antigen (sla) haplotype was not significant in the model, least-squares mean comparisons between haplotypes suggested that ac, dg, and gg pigs tended to have comparatively low preimmunization CH50 values. The model did not account for significant variability in postimmunization CH50 values, but least-squares means indicated that dd, dg, and gg haplotypes tended to have lower values than did other haplotypes tested. Mean CH50 units for 8- and 12-week-old pigs were 41.32 ± 20.49 and 59.50 ± 54.35, respectively. There was a significant difference (P < 0.001) in CH50 activity between 8- and 12-week-old pigs associated with immunization, because CH50 of nonimmunized controls did not differ at 8 and 12 weeks.
Cerebrospinal fluid analysis of rabid and vaccinia-rabies glycoprotein recombinant, orally vaccinated raccoons (Procyon lotor)
Authors: Hanlon Cathleen A. , Ziemer Ellen L. , Hamir Amir N. , Rupprecht Charles E. 
Published: February 2025

SUMMARY
Cerebrospinal fluid obtained from clinically normal free-ranging raccoons was analyzed and compared with csf obtained from raccoons vaccinated orally with vacciniarabies glycoprotein (v-rg) recombinant virus vaccine and subsequently challenged peripherally with street rabies virus, and csf from naive, rabies virus challenge-exposed control raccoons. Significant differences were not found in csf of free-ranging or v-rg recombinant virus vaccine recipient raccoons, and there was no evidence of cns invasion by v-rg virus. The csf of naive, rabies challenge-exposed control raccoons contained high numbers of lymphocytes and monocytes, compatible with rabies virus encephalitis. Although v-rg orally vaccinated challenge-exposed raccoons were protected from lethal rabies virus infection, a mild lymphocytic pleocytosis was evident at 90 days after challenge exposure.
Effects of ischemia and dimethyl sulfoxide on equine jejunal vascular resistance, oxygen consumption, intraluminal pressure, and potassium loss
Authors: Arden Warwick A. , Stick John A. , Parks Andrew H. , Chou Ching-Chung , Slocombe Ronald F. 
Published: February 2025

SUMMARY
Physiologic effects of 1 hour of ischemia and 1 hour of reperfusion on equine jejunum and protective effects of systemic administration of dimethyl sulfoxide (dmso, 1 g/kg of body weight) were investigated in 18 ponies, using neurally intact segments of jejunum perfused at constant flow with heparinized blood. Ponies were allotted to 4 groups: group 1, saline solution administered (control, n = 3); group 2, dmso administered (dmso, n = 3); group 3, ischemia induced and saline solution administered (ischemia, n = 6); and group 4, ischemia induced and dmso administered (ischemia-dmso, n = 6). Intestinal vascular resistance (r, mm of Hg/ml/min/100 g), oxygen consumption (Vo2, ml/min/100 g), frequency and amplitude of rhythmic changes in intraluminal pressure, intestinal compliance (c, ml/mm of Hg), and arteriovenous potassium concentration difference (Δav[K+], mEq/L) were determined and compared with stable preischemic values within groups. There were no significant changes in any variable in ponies of groups 1 or 2. In ponies of group 3, significant (P ≤ 0.05) changes included: an initial increase in r during reperfusion, followed by a decrease to values below preischemic values by 15 minutes of reperfusion; decreased Vo2 during the entire reperfusion period; increased amplitude of rhythmic contractions during initial reperfusion; decreased frequency of rhythmic contractions during ischemia; and increased Δav[k+] during initial reperfusion. Changes in ponies of group 4 were identical to changes in ponies of group 3, with the exception that dmso administration prevented the decrease in r during reperfusion. Although the action of dmso in modulating postischemic vascular reactivity may warrant further investigation, its failure to maintain tissue Vo2 or prevent tissue potassium loss suggested that dmso was not effective in preventing equine jejunal injury resulting from complete arterial occlusion followed by reperfusion.
Effect of clindamycin on Factor-VII activity in healthy cats
Authors: Jacobs Gilbert , Lappin Michael , Marks Amanda , Greene Craig E. 
Published: February 2025

SUMMARY
Four healthy cats were given clindamycin orally in daily doses of 25 or 50 mg/kg of body weight for 6 weeks. Significant change in Factor-VII activity was not found, compared with pretreatment values. In 2 cats tested, toxin produced by Clostridium difficile was not detected in fecal samples obtained before treatment and at 6 weeks after treatment, suggesting that intestinal overgrowth by C difficile did not develop. Results of the study seemed to indicate that orally administered clindamycin does not measurably reduce synthesis of vitamin K-dependent clotting factors in healthy cats.
Pharmacokinetics of sulfadiazine/trimethoprim in neonatal male calves: Effect of age and penetration into cerebrospinal fluid
Authors: Shoaf Susan E. , Schwark Wayne S. , Guard Charles L. 
Published: February 2025

SUMMARY
Sulfadiazine (sdz)/trimethoprim (tmp; 30 mg of sdz/tmp/kg of body weight) was given iv to the same 6 male calves at 1, 7, and 42 days of age and to 2 additional calves at 7 days of age. Serum concentrations of sdz and tmp were best represented by a 2-compartment open model, but in 42-day-old calves, csf concentrations of both drugs were best represented by a 1-compartment open model with first-order input. Between 1 and 42 days of age, the elimination half-life () of sdz decreased from 5.7 to 3.6 hours, and total body clearance (CLtot) increased from 1.43 to 1.88 ml/min/kg; the area under the curve (AUC0→∞) decreased from 291.5 to 225.4 mg/L·h. The distribution coefficient (Vd(area)/kg of body weight) decreased with age, changing from 0.72 to 0.59 L/kg, between 1 and 42 days of age.
Therapeutic concentrations of sdz in serum (> 2 μg/ml) were maintained for 24 hours in 1-day-old calves and for about 15 hours in 7- and 42-day-old calves. The elimination rate of tmp increased about 9-fold; was 8.4, 2.1, and 0.9 hours, respectively, at 1, 7, and 42 days of age. Other values also reflected an increase in tmp elimination rate with age: CLtot increased from 2.8 to 12 to 28.9 ml/min/kg, k13 increased from 0.336 to 0.654 to 1.664/h and AUC0→∞ decreased from 32.8 to 7.9 to 3.1 mg/L·h, respectively. Therapeutic concentrations (> 0.1 μg/ml) were maintained for 15 hours, 8 hours, and about 6 hours in 1-, 7-, and 42-day-old calves, respectively. Penetration of sdz and tmp into the csf in 42-day-old calves was substantial; ratios of AUCCSF/AUCserum were 0.60 and 0.69, respectively.
Therapeutic concentrations of drugs in csf were maintained if serum concentrations were above therapeutic concentrations; elimination rates of both drugs from the csf equaled those of serum. Sulfadiazine was excreted mainly unchanged; the percentage of dose excreted unchanged in 24 hours increased from 22.1 to 47.8 to 50.8% in 1-, 7-, and 42-day-old calves, respectively, paralleling the increase in CLtot. Trimethoprim was extensively biotransformed; the percentage of dose excreted unchanged in the urine in 24 hours decreased from 12.8 to 8.7 to 3.5%. Sulfadiazine and tmp were concentrated in the urine, and therapeutic concentrations of both drugs in urine were maintained for > 24 hours in calves of all ages.
Hematologic changes induced by intravenous administration of diacetoxyscirpenol in pigs, dogs, and calves
Authors: Coppock R. W. , Hoffmann W. E. , Gelberg H. B. , Bass D. , Buck W.B. 
Published: February 2025

SUMMARY
Diacetoxysscippenol (das) was given iv to pigs (0, 0.5, and 1.0 mg/kg of body weight), cattle (0 and 0.5 mg/kg), and dogs (0 and 0.5 mg/kg). Blood was collected and hemograms were done at 0.5-hour intervals for 8 hours. The animals were euthanatized at 8 hours after treatment, and bone marrow samples were taken and examined by light microscopy. Moderate to severe necrosis of bone marrow hematopoietic elements was found in animals given das. The sequential increase in the type and number of abnormal cells in the blood suggested a successive destruction of the hematopoietic elements. A marked left shift in the neutrophil population was found in animals given das. Metarubricytes and large platelets were found in the blood of animals given das. Lymphocytes were replaced with immature cells. Pathologic changes were most severe in the pigs given a dosage of 1.0 mg of das/kg. The order of species sensitivity to das was pigs > dogs >> cattle.