bluuebunny/crossref_metadata_2025_split huggingface dataset:
In vitro antimicrobial activity of sulfonamides against some porcine pathogens
Authors: Mengelers M. J. B. , van Klingeren B. , van Miert A. S. J. P. A. M. 
Published: February 2025

SUMMARY
The minimal inhibitory concentrations (mic) of sulfonamides were determined against Bordetella bronchiseptica (n = 10), Pasteurella multocida (n = 10), Haemophilus pleuropneumoniae (n = 20), and Streptococcus suis (n = 10) strains isolated from pigs with atrophic rhinitis, pneumonia, or meningitis.
Sulfonamides tested in an agar dilution method were sulfachloropyridazine, sulfadiazine, sulfadimethoxine, sulfamethazine, sulfadoxine, sulfisoxazole, sulfamerazine, sulfamethoxazole, sulfamethoxypyridazine, sulfanilamide, sulfatroxazole, and sulfisomidine.
Results indicated that monotherapy of S suis infections with sulfonamides should not be encouraged because the mic50 of all sulfonamides investigated was > 32 μg/ml. The mic50 of the sulfonamides against B bronchiseptica ranged from 0.5 to 8 μg/ml, against P multocida from 2 to 32 μg/ml, and against H pleuropneumoniae from 8 to 64 μg/ml.
The mic50 of sulfachloropyridazine, sulfadiazine, sulfadimethoxine, sulfamerazine, and sulfamethoxazole for the gram-negative bacteria did not exceed 16 μg/ml. Among these compounds, sulfamethoxazole had the highest activity. The frequently prescribed sulfamethazine had an overall low antimicrobial activity.
Effects of inoculations with Eimeria zuernii on young calves treated with decoquinate or narasin with or without dexamethasone
Authors: Fitzgerald P. R. , Mansfield M. E. 
Published: February 2025

SUMMARY
Sixteen 7-week-old Holstein male calves were inoculated with sporulated oocysts of Eimeria zuernii. Four calves (controls) were euthanatized and necropsied at 14 and 20 days after inoculation (dai). Two calves were treated with 20 mg of dexamethasone (im) on 13, 14, and 15 dai and euthanatized and necropsied 17 dai and 2 calves were given similar treatments and necropsied 20 dai. The 8 other calves were euthanatized and necropsied 20 dai. Two were started on the anticoccidial drug decoquinate in feed 13 dai; 2 others were given decoquinate on the same schedule plus dexamethasone on 13, 14, and 15 dai. Two calves were given the antibiotic narasin in feed beginning 13 dai and 2 calves were given parasin on the same schedule plus dexamethasone on 13, 14, and 15 dai.
All calves, except 2 controls necropsied 14 dai and 4 calves given decoquinate, discharged moderate-to-large numbers of oocysts in feces and had moderate-to-severe changes in fecal consistency. Histologic examintions revealed large numbers of endogenous stages in tissues of calves treated or not treated with dexamethasone. Few endogenous stages were observed in tissues from calves that were given decoquinate or decoquinate plus dexamethasone. Calves given narasin or narasin plus dexamethasone had moderate-to-large numbers of endogenous stages in the tissues.
Endogenous prostaglandin F2α release induced by physiologic saline solution infusion in utero in the mare: Effect of temperature, osmolarity, and pH
Authors: Pascoe David R. , Stabenfeldt George H. , Hughes John P. , Kindahl Hans 
Published: February 2025

SUMMARY
Thirty mares with normal estrous cycles were allotted equally to 5 groups and infused with 250 ml of saline (NaCl) solution in utero on the seventh day after ovulation to test the effects of temperature, osmolarity, or pH of the saline solution on prostaglandin F2α (pgf2α) release and luteolysis. Intrauterine infusion of phosphate-buffered saline solution failed to alter the duration of the luteal phase, compared with the control group. Similarly, increasing the temperature of phosphate-buffered saline solution to 42 C or increasing (600 mosm) or decreasing osmolarity (< 10 mosm) did not change the duration of the luteal phase. Decreasing the pH of saline solution to 3 caused significant (P < 0.0001) releases of pgf2α from the uterus within the first hour after infusion, and the luteal phase was shortened to 8.8 ± 1.0 days (mean ± sem; control, 15 ± 1.2 days). The results of this study showed that pH is the main factor in eliciting pgf2α release by intrauterine infusion of a saline solution, whereas increased temperature and osmolarity have no effect on the release of pgf2α.
Hemodynamic effects of high-frequency oscillatory ventilation in halothane-anesthetized dogs
Authors: Bednarski Richard M. , Muir William W. 
Published: February 2025

SUMMARY
Hemodynamic effects of spontaneous ventilation, intermittent positive-pressure ventilation (ippv), and high-frequency oscillatory ventilation (hfov) were compared in 6 dogs during halothane anesthesia. Anesthesia was induced with iv thiamylal Na and was maintained with halothane (end-tidal concentration, 1.09%). During placement of catheters, dogs breathed spontaneously through a conventional semiclosed anesthesia circuit. Data were collected, and dogs were mechanically ventilated, using ippv or hfov in random order. Ventilation was adjusted to maintain PaCO2 between 38 and 43 mm of Hg during ippv and hfov. Cardiac index, aortic blood pressure, and maximum rate of increase of left ventricular pressure were significantly (P < 0.05) less during hfov than during spontaneous ventilation, whereas right atrial and pulmonary artery pressure were significantly greater during hfov than during spontaneous ventilation. During ippv, only the maximum rate of increase of left ventricular pressure was significantly less than that during spontaneous ventilation.
Evaluation of the effects of intra-articular injection of dimethylsulfoxide on normal equine articular tissues
Authors: Welch R. D. , DeBowes R. M. , Liepold H. W. 
Published: February 2025

SUMMARY
To evaluate the effects of intra-articular injection of dimethylsulfoxide (dmso) on normal equine articular structures, 7 adult horses with clinically normal carpi were allotted to 2 treatment groups (group A, n = 4; group B, n = 3). In each horse after collection of synovial fluid samples, the right antebrachial carpal and middle carpal joints were aseptically injected with 2 ml of a 40% solution of 90% medical grade dmso in lactated Ringer solution, and the corresponding joints of the left forelimb (controls) were injected with 2 ml of lactated Ringer solution. In group-A horses, 2 ml of synovial fluid was obtained prior to injections of 40% dmso at 24 hours and 72 hours, for a total of 3 injections. At necropsy, synovial fluid, synovial membrane, and articular cartilage specimens were obtained. Group-B horses were injected with 40% dmso in the same sequence; however, the series was repeated following a 1-week interval.
Clinical evaluation of these horses revealed no evidence of carpal inflammation associated with any injection in any group. Synovial fluid analysis of dmso-injected and control joints revealed insignificant differences in leukocyte counts and total protein content.
There was no evidence of cartilage degradation on gross, histologic, or histochemical evaluation of any of the joints. Intercellular matrix staining of the articular cartilage failed to reveal any observable difference in glycosaminoglycan content between injection with dmso or lactated Ringer solution.
Numbers of Sertoli cells, quantitative rates of sperm production, and the efficiency of spermatogenesis in relation to the daily sperm output and seminal quality of young beef bulls
Authors: Berndtson William E. , Igboeli Gaius 
Published: February 2025

SUMMARY
Data from 34 yearling Hereford or Angus bulls were used to investigate relationships of testicular size, quantitative rates of sperm production, Sertoli cell numbers, numbers of germ cells supported per Sertoli cell, and the efficiency of spermatogenesis to daily sperm output and seminal quality. Two ejaculates were collected by electroejaculation from each bull on each of 2 days/week throughout the study. The percentage of progressively motile sperm and the percentage of morphologically normal sperm were determined from aliquots of fresh semen. Additional aliquots of semen were frozen in glass ampules or plastic straws and subsequently evaluated for postthaw motility and percentage of sperm with intact acrosomes. Sertoli cell numbers, the numbers of germcells per Sertoli cell, and the efficiency of spermatogenesis were unrelated to the quality of fresh or frozen semen (P > 0.05). In first ejaculates, the numbers of sperm and motile sperm were related (P < 0.05) to testicular parenchymal weight (r = 0.38 and 0.50), daily sperm production (r = 0.45 and 0.53), and spermatids per gram of testicular parenchyma (r = 0.35 and 0.34). Testicular parenchymal weight and daily sperm production also were related to daily sperm output and to the average daily motile sperm output of these bulls (P < 0.05), but could account for < 25% of the variability in these end points among bulls.
Interaction of turkey complement with Escherichia coli isolated from turkeys
Authors: Ellis Marlene G. , Arp Lawrence H. , Lamont Susan J. 
Published: February 2025

SUMMARY
The role of turkey complement in a serum bactericidal reaction was determined using serum-sensitive and serum-resistant Escherichia coli isolated from turkeys. Inactivation of complement by heating serum (56 C for 40 minutes) or by treating serum with 10 mM EDTA eliminated bactericidal activity. Serum-sensitive E coli organisms were killed by turkey serum treated with 10 mM ethylene glycol-bis-β-(aminoethyl ether)-N,N,N',N'-tetraacetic acid and 5 mM MgCl2. Exposure of normal turkey serum to serum-sensitive or serum-resistant E coli resulted in equivalent reductions in hemolytic activity of serum. Treatment of serum-resistant E coli with antibody rendered the bacteria sensitive to bactericidal effects of normal turkey serum. Serum-sensitive E coli organisms were readily killed by an alternative complement pathway, serum-sensitive and serum-resistant E coli activated the complement system equally well, and antibody was required for complement-mediated killing of certain serum-resistant E coli organisms from turkeys.
Kinematic analysis of cutting horses working a mechanical flag
Authors: Clayton Hilary M. 
Published: February 2025

SUMMARY
High-speed cinematography was used to record the movements of 12 cutting horses performing a standard test with a mechanical flag. Based on their previous competitive performances, horses were classified into 2 groups: group 1, composed of 5 moderately successful or average performers that had won < $35,000 in purse money; and group 2, composed of 7 highly successful or elite performers that had amassed > $35,000 in competition earnings. Analysis of the results indicated that, compared with horses of the average group, the elite horses had faster reaction times in response to the start and cessation of flag movement (P < 0.01), and were positioned closer to the flag during all stages of the trial (P < 0.05). Discriminant analysis was used to construct a mathematical formula that could be used to classify an individual horse into 1 of the 2 alternative groups, based on the set of measurements. Two predictor variables were selected that described the maximal distance between the horse and the flag during the run and the part of the body that was moved first in response to the initial flag movement. The accuracy of the predicted group membership, compared with the actual group membership, was 100%.
Treatment of Brucella melitensis infection in mice by use of liposome-encapsulated gentamicin
Authors: Hernández-Caselles T. , Vera A. , Crespo F. , Villalaín J. , Gómez-Fernández J. C. 
Published: February 2025

SUMMARY
Liposomes with entrapped gentamicin were used to treat mice with infection attributable to Brucella melitensis. Liposomes bearing positive charge and formed by egg yolk lecithin, cholesterol, and stearylamine were effective in the elimination of B melitensis residing in liver and spleen. Negatively charged liposomes, formed by egg yolk lecithin, cholesterol, and dicetyl phosphate were also effective in suppression of the infection in liver, but were less so in suppression of the infection in the spleen. Free gentamicin was less effective than the encapsulated antibiotic. At 20 hours after administration of gentamicin encapsulated in liposomes, the gentamicin concentrations in liver and spleen were similar, regardless of the charge of the liposomes—neutral, positive, or negative. However, positively charged liposomes were more efficient than were other liposome types for the treatment of brucellosis caused by B melitensis.
Response of equine airway smooth muscle to acetylcholine and electrical stimulation in vitro
Authors: Mason Diane E. , Muir William W. , Olson Lynne E. 
Published: February 2025

SUMMARY
Smooth muscle strips from the midcervical portion of the trachea and bronchial smooth muscle strips from third-generation airways of horses were placed in tissue baths, and isometric contractile force was measured. Active force was measured in response to electrical stimulation and exogenous acetylcholine. Square-wave electrical stimuli were applied at various voltages (10, 12, 15, 18, 20, 25 V), frequencies (3, 5, 10, 15, 20, 25, 30 Hz), and pulse durations (0.2, 0.5. 1.0. 1.5, 2.0 ms). Isometric contractile force increased as voltage, frequency, and pulse duration increased. Maximal contractile response to electrical stimulation was obtained at 18 V, 25 Hz, and 0.5 ms. Atropine (10-6M) or tetrodotoxin (3 × 10-6M) blocked the contraction, indicating that the contractile response was attributable to the release of neurotransmitter from cholinergic nerves.
Cumulative concentration-response curves to acetylcholine (10-9M through 10-4M) were determined. Isometric contractile force increased as acetylcholine concentration increased. There was a significant (P < 0.05) difference in the 50% effective dose for acetylcholine in tracheal smooth muscle and bronchial smooth muscle. The mean (± sd) contractile reponse to maximal electrical stimulus was 89% (± 7.4%) of that in response to 10-4M acetylcholine in tracheal smooth muscle and was 68% (± 10.4%) of the response to 10-4M acetylcholine in bronchial smooth muscle.
Interaction between Pasteurella haemolytica, sulfadiazine/trimethoprim, and bovine viral diarrhea virus
Authors: Clarke Cyril R. , Short Charles R. , Corstvet Richard E. , Nobles Debbie 
Published: February 2025

SUMMARY
A study was designed to develop and define a sc tissue chamber as a suitable device for establishing a soft-tissue infection model in cattle and to use this model to study the interaction between Pasteurella haemolytica, sulfadiazine/trimethoprim, and bovine viral diarrhea virus (bvdv). Thermoplastic tissue chambers were implanted in the paralumbar fossae of 20 calves. At 35 days after implantation, calves were allotted to 4 groups of equal size and the calves in 2 groups were inoculated intratracheally with a New York-1 strain of bvdv. At 45 days after implantation, all chambers were inoculated with a 6-hour culture of P haemolytica serotype 1. Starting 36 hours after bacterial inoculation, sulfadiazine/trimethoprim was administered iv once a day to half of the virus-inoculated calves and to half of those calves that had not been exposed to virus. Inoculation of P haemolytica into tissue chambers resulted in the establishment of a localized soft-tissue infection, characteristic of pneumonic pasteurellosis. Despite the maintenance of chamber antimicrobial concentrations that exceeded minimal bactericidal concentrations established in vitro, the infections were not sterilized. This lack of efficacy was associated with decreased pH and increased protein concentrations in chamber fluids after inoculation. Infection with bvdv, which is thought to depress host defenses, had no effect on the response of P haemolytica to sulfadiazine/trimethoprim administration. Observation of responsive antibody titers, bacterial phagocytosis, and high leukocyte viability within P haemolytica-infected chambers documented functional host defenses within tissue chambers.
Influence of isoprinosine on lymphocyte function in virus-infected feeder pigs
Authors: Flaming K. P. , Blecha F. , Fedorka-Cray P. J. , Anderson G. A. 
Published: February 2025

SUMMARY
Pseudorabies is a porcine herpesvirus of major importance in the swine industry. Isoprinosine is an immunomodulating drug that has been shown to be beneficial in treating herpesvirus infections. Twenty-four 7-week-old pigs were allotted within litters to 1 of 4 groups: control, isoprinosine (iso), pseudorabies virus (prv), or isoprinosine and pseudorabies virus (iso-prv). Isoprinosine was administered daily for 16 days to the iso and iso-prv groups (75 mg/kg of body weight/day, po). Immunity in pigs in the prv and iso-prv groups was challenged with pseudorabies virus (105 tcid50 units) on day 4. Rectal temperatures and viral excretion were monitored daily; total and differential leukocyte counts, lymphocyte response to mitogens, and interleukin-2 production were monitored every 4 days. Pigs challenge-inoculated with pseudorabies virus became ill, with the iso-prv group most severely affected. Rectal temperatures were high (P < 0.05) in virally challenged pigs on days 5 to 12 and 14 to 16; isoprinosine did not alter this effect. Pseudorabies virus-infected pigs had leukocytosis (P < 0.05) on days 12 and 16, primarily caused by neutrophilia. Concanavalin A-stimulated lymphocyte proliferation was decreased (P < 0.06) in both prv and iso-prv groups on day 12, compared with control pigs, but only in the prv group on day 16. Pokeweed mitogen-stimulated lymphocyte proliferation was decreased (P < 0.02) in iso-prv pigs on day 8 of the experiment. Interleukin-2 concentrations, pooled over all sampling days, were decreased (P < 0.03) in pseudorabies virus-infected pigs. Viral excretion was not altered by isoprinosine treatment. These data suggest that pseudorabies virus infection decreased lymphocyte proliferative responses and interleukin-2 production in pigs, and that isoprinosine did not mitigate these effects.
Isoproterenol- and salbutamol-induced relaxation of acetylcholine- and histamine-induced contraction of equine trachealis muscle in vitro
Authors: Olson L. E. , Perkowski S. Z. , Mason D. E. , Muir W. W. 
Published: February 2025

SUMMARY
Strips of trachealis muscle were dissected from the mid-cervical portion of the trachea of horses that were free of y respiratory tract disease, and the overlying epithelium and mucosa were removed. Muscle strips were suspended in tissue baths that were filled with Krebs-bicarbonate solution, aerated with 5% CO2 in oxygen and maintained at 37 C. Isometric tension was continuously recorded. The increase in active isometric tension was concentration dependent when acetylcholine (10−9 to 10−4M) or histamine (10−9 to 10−4M) was added to the tissue baths in 0.5-logarithmic increments. When the tissues were contracted with acetylcholine (3.1 × 10−6M) or histamine (10−4M), the decrease in active isometric tension was concentration dependent when isoproterenol (10−9 to 10−4M or salbutamol (10−9 to 10−4M) was added to the tissue baths in 0.5-logarithmic increments. There was no difference between the response to isoproterenol and salbutamol when tissues from the same horses were compared whether the tissues were contracted in response to acetylcholine (3.1 × 10−6M) or histamine (10−4M). Relaxation was antagonized by 10−6M propranolol. The degree of relaxation obtained in these muscle strips was considerably less than that reported from other species’ tracheal muscle strips that had the epithelium and mucosa intact. We concluded that equine tracheal smooth muscle contains β-adrenoceptors that can be stimulated by either a mixed β-1, β-2 agonist or a selective β-2 agonist.
Effect of probenecid administration on cephapirin pharmacokinetics and concentrations in mares
Authors: Juzwiak James S. , Brown Murray P. , Gronwall Ronald , Houston A. E. 
Published: February 2025

SUMMARY
Cephapirin (20 mg/kg of body weight, iv) was administered before and after 3 doses of probenecid (25, 50, or 75 mg/kg, intragastrically, at 12-hour intervals) to 2 mares. Clearance and apparent volume of distribution, based on area under the curve, were negatively correlated with probenecid dose. Clearance of cephapirin was decreased by approximately 50% by administration of 50 mg of probenecid/kg.
Serum, synovial fluid, peritoneal fluid, csf, urinary, and endometrial concentrations of cephapirin were determined after 5 doses of cephapirin (20 mg/kg, im, at 12-hour intervals) without and with concurrently administered probenecid (50 mg/kg, intragastrically) to 6 mares, including the 2 mares given cephapirin, iv. Highest mean serum cephapirin concentrations were 16.1 ± 2.16 μg/ml at 0.5 hour after the 5th cephapirin dose [postinjection (initial) hour (pih) 48.5] in mares not given probenecid and 23.7 ± 1.30 μg/ml at 1.5 hours after the 5th cephapirin dose (pih 49.5) in mares given probenecid. Mean peak peritoneal fluid and synovial fluid cephapirin concentrations were 6.2 ± 0.57 μg/ml and 6.6 ± 0.58 μg/ml, respectively, without probenecid administration and 12.3 ± 0.46 μg/ml and 10 ± 0.78 μg/ml, respectively, with concurrent probenecid administration.
Mean trough cephapirin concentrations for peritoneal and synovial fluids in mares given probenecid were 2 to 3 times higher than trough concentrations in mares not given probenecid. Overall mean cephapirin concentrations were significantly higher for serum, peritoneal fluid, synovial fluid, and endometrium when probenecid was administered concurrently with cephapirin (P < 0.01). Cephapirin was not detected in csf samples. Overall mean urinary cephapirin concentrations (2.47 mg/ml without concurrent probenecid administration and 3.06 mg/ml with concurrent probenecid) were not significantly different (P > 0.05). Mean trough serum probenecid concentration was 61.2 ± 5.28 μg/ml. Highest serum probenecid concentration was 148.8 ± 5.97 μg/ml, 2 hours after the 5th cephapirin dose (pih 50). Probenecid administration increased serum, synovial fluid, peritoneal fluid, and endometrial concentrations of cephapirin in mares.
Whole blood platelet aggregation in uremic dogs
Authors: Forsythe LeeAnn T. , Jackson Marion L. , Meric Susan M. 
Published: February 2025

SUMMARY
Whole blood platelet aggregation responses to collagen, arachidonic acid, and adenosine diphosphate were determined by use of the impedance method in 22 dogs with serum urea concentrations ≥ 20 mmol/L, which was attributable to renal disease, and in 25 healthy control dogs. The median changes in impedance for the control dogs were 23 ohms for collagen, 18 ohms for arachidonic acid, and 6 ohms for adenosine diphosphate. The median changes in impedance in uremic dogs were 25 ohms for collagen, 21 ohms for arachidonic acid, and 15 ohms for adenosine diphosphate. There were no significant differences in platelet aggregation responses to collagen, arachidonic acid, and adenosine diphosphate between uremic and control dogs. Hemorrhagic tendencies were not detected in uremic dogs by use of whole blood platelet aggregation. Results of this study suggest that platelet aggregation by use of the whole blood platelet aggregometer is not abnormal in uremic dogs, but does not exclude the possibility of a platelet aggregation defect undetected by the whole blood system.
Serum distribution of iodine after oral administration of ethylenediamine dihydriodide in cattle
Authors: Maas J. , Berg J. N. , Petersen R. G. 
Published: February 2025

SUMMARY
Serum concentrations of iodine were determined after cattle were given ethylenediamine dihydriodide (eddi) orally at dosages ranging from 0.0 (placebo) to 0.77 mg/kg of body weight/day. The serum iodine concentration was correlated with the dosage of eddi. A rate of 0.11 mg eddi/kg/day was correlated with serum iodine concentrations (20 to 80 μg/dl) previously found to be effective in preventing foot rot in cattle. A linear dose-response curve that was generated could be helpful in predicting dosage of eddi if the serum iodine concentration is known.