bluuebunny/crossref_metadata_2025 huggingface dataset:
Effects of animal and soy fats and proteins in the diet on fatty acid concentrations in the serum and skin of dogs
Authors: Campbell K. L. , Czarnecki-Maulden G. L. , Schaeffer D. J.
Published: January 2024

Growing dogs were fed diets containing soy oil or poultry fat as the main fat source and soybean meal or meat meal as the main protein source to examine the effects of types of dietary fat and protein on fatty acid concentrations in serum and skin and on serum cholesterol concentrations. Dogs fed diets containing soy oil had higher serum linoleic acid concentrations and lower serum oleic acid, arachidonic acid, and cholesterol concentrations than dogs fed diets containing poultry fat. The type of dietary protein had marginal effects on fatty acid concentrations and did not affect serum cholesterol. Similar differences were found in cutaneous fatty acid concentrations, with soy oil-fed dogs having significantly (P < 0.05) higher linoleic acid and lower oleic acid concentrations in their skin than had poultry fat-fed dogs. This study suggested that dietary fat source influences serum and cutaneous fatty acid concentrations and serum cholesterol concentrations in dogs, irrespective of dietary protein source.
Effects of giardiasis on production in a domestic ruminant (lamb) model
Authors: Olson M. E. , McAllister T. A. , Deselliers L. , Morck D. W. , Cheng K.-J. , Buret A.G. , Ceri H.
Published: January 2024

Objective

To examine the effects of giardiasis on production and carcass quality, using growing lambs as a domestic ruminant model.

Design

Randomized block.

Animals

Giardia-free lambs: 23 in infected group, 24 in control group.

Procedure

Six-week-old, specific-pathogen-free lambs were infected with Giardia trophozoites; control lambs received saline solution. Clinical signs of infection, body weight, and feed intake were determined for 10 weeks. Carcass weight and quality were determined at slaughter weight of 45 kg.

Results

Giardia infection persisted from weeks 7 to 16. For 5 weeks after challenge exposure, abnormal feces were more frequently observed in infected lambs. Giardia infection was associated with a decrease in rate of weight gain and impairment in feed efficiency. Time to reach slaughter weight was extended in infected lambs, and the carcass weight of Giardia-infected lambs was lower than that of control lambs.

Conclusion

Giardiasis has a negative effect on domestic ruminant production.

Clinical Relevance

Giardiasis in domestic ruminants is an economically important disease, thus necessitating control or elimination of the infection.
Effects of hydrogen peroxide on isolated trachealis muscle of horses
Authors: Olszewski Michal A. , Robinson N. Edward , Yu Ming-Fu , Derksen Frederik J.
Published: January 2024

During acute bouts of recurrent airway obstruction (heaves) in horses, neutrophils that are capable of increased production of reactive oxygen species accumulate in the airways. In the study reported here, the effect of hydrogen peroxide (H2O2; 1 µM to 0.1M), one of these reactive oxygen species products, on the responses of isolated trachealis muscle of horses was determined. Before and after incubation with H2O2, contractile responses to acetylcholine, electrical field stimulation (efs), 127 mM KCl, and relaxation responses to isoproterenol and activation of the nonadrenergic noncholinergic inhibitory response (iNANC) were evaluated. Beginning at 1 mM, H2O2 contracted trachealis muscle in a concentration-dependent manner. This contraction was unaffected by atropine (1 µM), tetrodotoxin (1 µM), or 1 µM meclofenamate. Contraction of trachealis muscle in response to H2O2 is, therefore, not attributable to release of prostaglandins, acetylcholine, or other neurotransmitters. Above a concentration of 0.1 mM, H2O2 depressed the responses to efs, acetylcholine, and KCl in a concentration-dependent manner. At 0.1M, H2O2 decreased the maximal responses to efs, acetylcholine, and KCl by 62.7 ± 7.2, 60.58 ± 6.12, and 37.8 ± 9.54%, respectively. In the presence of meclofenamate (1 µM), partial but significant protection against 1 to 100 mM H2O2 was observed. In tracheal strips contracted with 0.3 µM methacholine, H2O2 had no effect on the isoproterenol concentration-response curve. Up to a concentration of 100 mM, H2O2 had no effect on iNANC response. However, in the presence of 100 mM H2O2, this response was abolished in 2 of 4 horses. We conclude that high concentrations of H2O2 affected the responses of airway smooth muscle by actions on neurotransmission, muscarinic receptors, and downstream from receptors; some of the H2O2 effects were in part mediated by cyclooxygenase products; and H2O2 had no effect on β-adrenergic or iNANC-induced relaxation.
Down-regulation of β-adrenergic receptors and up-regulation of estrogen and progesterone receptors induced in the reproductive system of female veal calves by dietary clenbuterol
Authors: Re Giovanni , Badino Paola , Novelli Antonella , Girardi Carlo
Published: January 2024

Effects induced by long-term administration of clenbuterol at anabolic dosages (20 µg/kg of body weight for 40 days) on β-adrenergic receptor (β-ar) subtypes, estrogen receptors (er), and progesterone receptors (PgR) in the reproductive system of female veal calves were investigated. Clenbuterol treatment induced a significant (P < 0.01) down-regulation of β-ar subtypes (β1-ar, β2-ar, myometrial high-affinity β2-ar, and ovarian low-affinity β2-ar). On the other hand, a significant (P < 0.01) increase of uterine and ovarian er and PgR receptors was observed in treated calves. Treatment did not affect dissociation constant values of β-ar, er, or PgR. In similar manner, clenbuterol did not significantly modify distribution of er and PgR in the various tissues of the genital tract. In fact, these receptors were significantly (P < 0.05) more concentrated in the uterus than in the vagina in treated and untreated calves. Data indicated that prolonged clenbuterol exposure induced homologous β-ar down-regulation (down-regulation of its specific receptors) and heterologous er and PgR up-regulation (up-regulation of different types of receptors, not specifically bound by clenbuterol) in the genital tract of veal calves. Modification of the receptorial status could be reasonably related to the pathologic changes observed in long-term treated calves (eg, hydrometra, dilatation of uterine glands, cystic ovaries). The increased concentrations of er and PgR suggested the possible existence of subcellular mechanisms regulated by repeated β-adrenergic stimulation.
Icterus in bob veal calves and its association with lack of colostrum intake and high serum creatine kinase activity
Authors: Gray Mary L. , Bounous Denise I. , Kelley Lynda C. , Almazan Pedro , Brown John
Published: January 2024

Icterus condemnations compose a substantial proportion (41%) of total condemnations of bob veal, the class of veal composed of calves < 3 weeks old and weighing up to 68 kg. At postmortem examination, bob veal condemned because of icterus have generalized yellow discoloration of tissues, which is commonly associated with large, yellow liver (fatty liver), and a paucity of other gross pathologic changes. To establish that the generalized yellow discoloration was attributable to high tissue bilirubin concentrations and to examine the underlying mechanism(s) that might be responsible, blood samples and tissue specimens were obtained from clinically normal and icteric bob veal calves at slaughter. For comparison, blood samples were collected from clinically normal, 1- to 5-day-old Holstein calves being raised on local dairy farms. Hematologic and serum biochemical analyses were obtained for the 3 groups of calves (normal local, normal slaughter, and icteric slaughter), and tissues of slaughter calves were examined for histologic evidence of inflammatory or degenerative changes. Mean ± sd total bilirubin concentration and creatine kinase (ck) activity in icteric bob veal (3.3 ± 0.8 mg/dl; 869 ± 788 U/L), normal bob veal (1.4 ± 0.7 mg/dl; 486 ± 890 U/L), and normal local calves (0.5 ± 0.2 mg/dl; 156 ± 158 U/L) were significantly different. When data for both normal and icteric bob veal calf groups were combined for analysis, total bilirubin concentration regressed significantly on hepatic lipid scores (P = 0.00003) and ck activity (P = 0.00049). Colostrum consumption was determined by measuring serum total protein concentration and serum γ-glutamyltransferase activity. Bob veal calves that had not consumed colostrum had significantly higher total bilirubin (P = 0.00005) and ck (P = 0.0008) values. It was concluded that normal and icteric bob veal calves have significant increase in total bilirubin concentration, and icterus of bob veal calves is secondary to unconjugated hyperbilirubinemia. Lack of colostrum consumption was strongly correlated with icterus in bob veal calves.
Comparison of N-acetylcysteine and methylene blue, alone or in combination, for treatment of acetaminophen toxicosis in cats
Authors: Rumbeiha Wilson K. , Lin Yu-Shang , Oehme Frederick W.
Published: January 2024

Acetaminophen is widely used in human beings for analgesic purposes, but is one of the most frequent causes of poisoning in cats. Acetaminophen-poisoned cats develop methemoglobinemia and sometimes hepatic failure. To determine the benefit of using methylene blue, a treatment for methemoglobinemia, along with N-acetylcysteine (nac), the recommended treatment for acetaminophen-poisoned cats, groups of 3 male and 3 female cats each were given methylene blue nac, or both after administration of acetaminophen (120 mg/kg of body weight, po). Male cats seemed more susceptible than female cats to acetaminophen toxicosis, because 3 males died of hepatic failure (2 cats given acetaminophen/methylene blue and 1 given acetaminophen/nac/methylene blue). Although nac alone seemed to elicit the best overall response, methylene blue, alone or in combination with nac, may be useful in female cats.
Effect of flunixin meglumine on endogenous prostaglandin F2α secretion during cloprostenol-induced abortion in mares
Authors: Daels P. F. , Mohammed H. O. , Odensvik Kristina , Kindahl H.
Published: January 2024

Objective

To determine the relative role of endogenous prostaglandin F2α (pgf2α secretion in cloprostenol-induced abortion in mares that no longer require luteal progesterone secretion for maintenance of pregnancy, and to evaluate the ability of a prostaglandin cyclooxygenase inhibitor (flunixin meglumine) to prevent cloprostenol-induced abortion.

Design

The effect of flunixin meglumine on pgf2α secretion and outcome of pregnancy was compared between mares treated with cloprostenol only and mares treated with cloprostenol plus flunixin meglumine.

Animals

Five pregnant mares, aged 4 to 15 years, of light-horse type.

Procedure

Cloprostenol (250 μg) was administered at 24-hour intervals to 5 pregnant mares. Flunixin meglumine (500 mg, iv) was administered at 8-hour intervals starting 15 minutes before the first cloprostenol administration. Hourly blood samples were analyzed for 15-ke-todihydro-pgf2α, progesterone, and estrogen concentrations. Previously reported data on cloprostenol-induced abortion in 6 pregnant mares treated daily with cloprostenol only were used as historic controls.

Results

The mean (± sem) interval from first cloprostenol administration to fetal expulsion 56.4 (± 13.7) hours and number of cloprostenol administrations 3.2 (± 0.6) in the 5 flunixin meglumine-treated mares were not significantly different, compared with values for 6 pregnant mares treated daily with cloprostenol only, 48.6 (± 5.6) hours and 2.8 (± 0.2) cloprostenol administrations. Flunixin meglumine did not inhibit endogenous pgf2α secretion. Prostaglandin F2α secretion rates on the day before and day of fetal expulsion were similar in both groups.

Conclusion

Flunixin meglumine at a dosage of 500 mg/animal, administered iv every 8 hours, is ineffective in modulating uterine pgf2α secretion during cloprostenol-induced abortion.

Clinical Relevance

Flunixin meglumine is ineffective in the modulation of prostaglandin-induced uterine pgf2αsecretion and, therefore, does not offer a viable alternative for the prevention of abortion in mares at risk of abortion because of systemic illness.
Effect of coculture with stallion spermatozoa on de novo protein synthesis and secretion by equine oviduct epithelial cells
Authors: Thomas Philip G. A. , Ignotz G. G. , Ball B. A. , Brinsko S. P. , Currie W. B.
Published: January 2024

Adhesion of equine spermatozoa to homologous oviduct epithelial cells (oec) in vitro results in specific changes in spermatozoa and oec function. To test the hypothesis that adhesion of spermatozoa affects protein synthesis and secretion by oec, the following treatment groups were established in culture: oec with culture medium only; control spermatozoa in culture medium only; oec in coculture with spermatozoa; and oec and spermatozoa in coculture, but physically separated by a microporous membrane. The experiment was replicated within each of 4 ejaculates from 3 stallions. De novo protein secretion by oec was measured and compared by incorporation of [35S]methionine, and evaluated, using two-dimensional Polyacrylamide gel electrophoresis and fluorography. Monolayers of oec secreted a large number of proteins of molecular mass ranging from 14 to 205 kd. Adhesion of spermatozoa consistently caused reduced synthesis of 2 oec secretory proteins and new or increased synthesis of 6 proteins. When spermatozoa and oec were separated by a microporous membrane, some but not all of these changes were duplicated. Synthesis of 3 oec secretory proteins, unaffected by binding of spermatozoa, was reduced when spermatozoa were prevented from contact with oec by a microporous membrane. Adhesion of equine spermatozoa to homologous oec monolayers and presence of equine spermatozoa resulted in qualitative and quantitative changes in synthesis and secretion of proteins by oec. These changes have implications for storage, longevity, and maturation of spermatozoa.
Prevalence of coagulase-positive staphylococci, other than Staphylococcus aureus, in bovine mastitis
Authors: Roberson Jerry R. , Fox Lawrence K. , Hancock Dale D. , Gay John M. , Besser Thomas E.
Published: January 2024

Objective

To determine prevalence and relevance of coagulase-positive Staphylococcus hyicus and S intermedius intramammary infections (IMI) in dairy cows and determine the ability of the 4-hour tube coagulase (TC) test to differentiate the coagulase-positive staphylococci (CPS).

Design

Prevalence of CPS was determined for primiparous cows (point prevalence and prevalence at first parturition) and multiparous cows (point prevalence) of 2 herd groups: < 6% CPS IMI prevalence = low prevalence (LP); > 10% CPS IMI prevalence = high prevalence (HP).

Sample population

For prevalence, cows of 22 dairy herds. For TC, 1,038 CPS strains isolated from cow milk.

Procedure

Speciation of CPS from aseptically collected composite milk samples was performed. Coagulase-positive isolates from 4 cow groups were tested for their ability to coagulate rabbit plasma by 4 hours: LP and HP primiparous cows at parturition, and LP and HP cows any time after first parturition.

Results

Of 487 CPS in the prevalence study, 82.1% were S aureus, 17.7% were coagulase-positive S hyicus, and 0.2% were S intermedius. Of all CPS IMI in LP herds, 34% were coagulase-positive S hyicus; of all CPS IMI in HP herds, 9% were coagulase-positive S hyicus. Coagulase-positive S hyicus appeared to persist to the end of lactation in 4 cows (mean linear somatic cell count = 3.7). The TC test was ≥ 97% sensitive, ≤ 33% specific, and had a predictive value positive range of 60 to 97% for S aureus isolates.

Conclusion

Coagulase-positive S hyicus appears capable of inducing chronic, low-grade IMI. Staphylococcus intermedius does not appear to be an important mastitis pathogen. The TC test is not valid to use as the sole method to differentiate CPS species. (Am J Vet Res 1996;57:54-58)
Preliminary evaluation of antimicrobial agents for treatment of Leptospira interrogans serovar pomona infection in hamsters and swine
Authors: Alt David P. , Bolin Carole A.
Published: January 2024

Objective

To evaluate antimicrobial agents for treatment of models of acute and persistent leptospirosis caused by Leptospira interrogans serovar pomona.

Design

Randomized trials comparing dosages and regimens of various antimicrobial agents for treatment of acute and persistent leptospirosis.

Animals

245 Golden hamsters to model acute leptospirosis and 121 mixed-breed swine to model persistent leptospirosis.

Procedure

Hamsters and swine were inoculated with L interrogans serovar pomona. Antimicrobial agents were given to hamsters for 3 or 5 days after inoculation, with necropsy at 14 days after inoculation. Swine were treated for 1, 3, or 5 days beginning at 3 weeks after inoculation, and were necropsied 7 to 10 days after completion of antimicrobial agent treatment. Hamster tissue and swine tissue and urine specimens were examined by culture, fluorescent antibody testing, and histologic examination for presence of leptospires.

Results

All untreated control hamsters became infected and manifested clinical signs and lesions of acute leptospirosis. Leptospires were not detected in hamsters treated with dihydrostreptomycin/penicillin G (25 mg/kg of body weight). Administration of ampicillin at all dosages reduced the number of hamsters infected, as confirmed at necropsy; the other agents tested required dosages greater than label recommendations to reduce the number infected. All untreated control swine became infected and shed leptospires in urine through the time of necropsy. Leptospires were not detected in kidneys or urine of swine treated with dihydrostreptomycin/penicillin G (25 mg/kg) for 1, 3, or 5 days, or in swine treated with oxytetracycline (40 mg/kg for 3 or 5 days), tylosin (44 mg/kg for 5 days), or erythromycin (25 mg/kg for 5 days). Treatment with ceftiofur and ampicillin was not effective in elimination of L interrogans serovar pomona in swine.

Conclusions

Dihydrostreptomycin/penicillin G is effective for treatment of acute and persistent leptospirosis. Differences between the effectiveness of antimicrobial agents in the acute and persistent model of leptospirosis emphasize the importance of using the appropriate model for treatment evaluation. Antimicrobial agents evaluated for treatment of persistent leptospirosis in swine required the use of dosages above those recommended by the manufacturer.

Clinical Relevance

Use of antimicrobial agents at extra-label dosages for treatment of persistent leptospirosis may cause residue problems in food animals; however, these regimens may be useful for treatment of breeding stock or animals destined for import/export. (Am J Vet Res 1996;57:59-62)
Fractionation of canine serum calcium, using a micropartition system
Authors: Schenck Patricia A. , Chew Dennis J. , Brooks Charles L.
Published: January 2024

Objectives

To determine usefulness of a micropartition system for calcium fractionation of canine serum, and to establish reference values for protein-bound, complexed, and ionized calcium fractions in clinically normal dogs.

Design

Performance characteristics of a micropartition system were evaluated, using serum from clinically normal dogs. This micropartition system was then used to determine a reference range for calcium fractions.

Animals

13 clinically normal dogs.

Procedure

Dog serum was placed in the micropartition system, and spun for 20 minutes at 1,300 × g. Total calcium concentration, ionized calcium concentration, and pH were measured in whole serum, and total calcium concentration was measured in the ultrafiltrate. The protein-bound fraction was calculated by subtracting total calcium of the ultrafiltrate from total calcium of whole serum. The ionized calcium measurement of whole serum was subtracted from the total calcium measurement of the ultrafiltrate, determining the complexed calcium fraction.

Results

During validation of the ability of the micropartition system to separate calcium fractions, no significant amount of serum calcium was adsorbed by the plastic micropartition system or membrane. The micropartition membrane separated the protein-bound calcium fraction (retentate) from the ultrafiltrate, which contained ionized and complexed fractions of calcium. Concentrations of protein-bound, ionized, and complexed calcium from clinically normal dogs were determined to be 3.40 ± 0.63, 5.49 ± 0.17, and 1.01 ± 0.30 mg/dl, representing 34, 56, and 10% of the total calcium concentration, respectively.

Conclusions

This method is a rapid, repeatable means to completely fractionate serum calcium, and most importantly provides accurate assessment of the protein-bound and complexed calcium fractions.

Clinical Relevance

Complete assessment of calcium fractions may increase sensitivity for detection of disease processes that affect calcium metabolism.(Am J Vet Res 1996;57:268-271 )
Effect of dose on the immune response and persistence of Salmonella choleraesuis infection in swine
Authors: Gray Jeffrey T. , Stabel Thomas J. , Fedorka-Cray Paula J.
Published: January 2024

Objective

To establish the effect of dose on persistence of and immune response to Salmonella choleraesuis in swine.

Design

19 Salmonella-free pigs were allotted to 4 groups. Groups 1 (n = 5), 2 (n = 5), and 3 (n = 5) were inoculated intranasally with 109, 106, and 103 colony-forming units of S choleraesuis, respectively. Group 4 (n = 4) served as uninoculated controls.

Procedure

Pigs were monitored for clinical signs of disease and bacterial shedding. Serum and lymphocytes were obtained to measure immune responses. Pigs from groups 1, 2, and 4 were necropsied at postinoculation (PI) weeks 6 and 15. Pigs from groups 3 and 4 were necropsied at PI weeks 6 and 10.

Results

Pigs in group 1 shed S choleraesuis through PI week 15 and were tissue positive at PI weeks 6 and 15. Pigs in group 2 were tissue positive for S choleraesuis until PI week 6 and continued shedding through PI week 9. Salmonella choleraesuis was not recovered at any time from pigs in groups 3 or 4. Pigs in groups 1, 2, and 3 had serum IgG and IgM titers to S choleraesuis lipopolysaccharide and soluble antigens. Pigs in all groups had a lymphocyte response to concanavalin A, and pigs in groups 1 and 2 had a lymphocyte response to S choleraesuis endotoxin. Pigs in group 1 had a lower stimulation index in response to both antigens, indicating some form of lymphocyte immunosuppression.

Conclusions

Persistence of S choleraesuis in host tissues is dose dependent. Short-term persistence can occur after a dose as low as 106 colony-forming units of S choleraesuis. Higher doses result in development of longterm carrier status, which may be related to the observed lymphocyte immunosuppression.(Am J Vet Res 1996;57:313-319)
Pathogenesis of plaque variants of porcine reproductive and respiratory syndrome virus in pregnant sows
Authors: Park B. K. , Yoon I. J. , Joo H. S.
Published: January 2024

Objective

To determine whether porcine reproductive and respiratory syndrome virus plaque variants vary in their pathogenicity in causing late-term reproductive failure.

Design

Four groups of 2 sows each at 86 days of gestation were inoculated intranasally with PRRSV small (MN-Hs) and large (MN-HI) plaque variants, field isolate, and cell culture medium, respectively. In addition, 2 sows each at 86 days of gestation were inoculated intranasally or IM with MN-Hs virus.

Animals

14 pregnant sows.

Procedure

Inoculated sows were allowed to deliver at term, and each litter was examined for clinical abnormality and presence of virus.

Results

Two sows infected with MN-Hs virus delivered 14 live and 5 dead pigs, whereas 2 sows infected with MN-HI virus delivered 0 live and 25 dead pigs. Two sows inoculated with a field isolate (MN-W) delivered 10 live and 20 dead pigs. Two control sows had 26 normal fetuses at slaughter at 107 days of gestation. Virus was isolated from 16 (66.7%) of 24 liveborn pigs, 9 (64.3%) of 14 stillborn pigs, and 3 (12.0%) of 25 mummified fetuses of the 6 infected sows. Subsequently, 4 MN-Hs-infected sows delivered 40 live and 11 dead pigs.

Conclusions

Marked difference in the pathogenicity in pregnant sows between porcine reproductive and respiratory syndrome virus strains was documented. The MN-Hs virus is considered to be of low pathogenicity, but the other viruses are highly pathogenic for late-term pregnant sows.(Am J Vet Res 1996;57:320-323)
Effects of locally injected medications on healing of pad wounds in dogs
Authors: Swaim Steven F. , Vaughn Dana M. , Kincaid Steven A. , Morrison Nancy E. , Murray Susan S. , Woodhead Melissa A. , Hoffman Charles E. , Wright James C. , Kammerman John R.
Published: January 2024

Objective

To ascertain the effects of locally injected immunostimulant and tripeptide-copper complex (TCC) on improving healing of pad wounds.

Design

Wounds in pads of large dogs were injected with either medication or physiologic saline solution (controls). Healing was evaluated.

Animals

12 mature English Pointers.

Procedure

Full-thickness 6 × 8-mm wounds in metatarsal and third and fourth digital pads were injected with immunostimulant or TCC at 0, 3, and 6 days after wounding. Wounds on control dogs were injected with physiologic saline solution. Using planimetric measurements at 0, 3, 6, 14, and 21 days, rates of healing were evaluated. Biopsy of the digital pad wounds at 3, 6, and 14 days was used to evaluate collagen content by hydroxyproline analysis. Biopsy specimens were also evaluated for type-I and type-III collagen, using Sirius red differential staining.

Results

Effect on healing rate and hydroxyproline content was best during the first week for immunostimulant. Immunostimulant- and TCC-injected wounds had more type-I collagen than did controls at 6 days; TCC-injected wounds had the most type-I collagen. At 14 days, the amount of type-I collagen in TCC-injected wounds was significantly greater than that in other wounds.

Conclusions

Tested medications had positive effects on healing of pad wounds.

Clinical Relevance

Intralesional injection of medications helps ensure their presence for enhancement of wound healing. The benefit could be lost with topical use in a bandage if the bandage is lost or becomes wet.(Am J Vet Res 1996;57:394-399)
Scintigraphic evaluation of 99mTc-methylene diphosphonate uptake in the navicular area of horses with lameness isolated to the foot by anesthesia of the palmar digital nerves
Authors: Keegan Kevin G. , Wilson David A. , Lattimer Jimmy C. , Twardock A. Robert , Ellersieck Mark R.
Published: January 2024

Objective

To evaluate distribution and intensity of 99mTc-methylene diphosphonate (99mTc-MDP) uptake in the navicular area in horses with forelimb lameness isolated to the palmar aspect of the foot.

Design

Prospective, case-controlled study.

Animals

7 horses with clinical signs of navicular syndrome and 7 control horses.

Procedure

Palmar view, soft tissue-phase scintigraphic images of the foot were obtained between 7 and 12 minutes after injection of 120 to 170 mCi of 99mTc-MDP. Lateral and palmar view, bone-phase images were obtained at 30 minutes and 1, 2, and 4 hours after injection. Palmar views were evaluated by determining the ratio of image density in the navicular area to mean image density in the distal phalangeal area. Palmar and lateral view, bone-phase images were also scored on the basis of navicular area intensity (intense = 3, moderate = 2, mild = 1, and no uptake = 0). Density ratios and mean scores were evaluated as a three-way ANOVA.

Results

Mean navicular-to-distal phalangeal density ratio for affected horses (1.77) was significantly (P = 0.003) greater than that for control horses (0.97). The mean subjective score for affected horses when evaluating palmar views only (1.85) and when evaluating palmar and lateral view pairs together (1.99) was significantly (P < 0.01) higher than scores for control horses (0.51, 0.62). Images obtained 1 hour after injection were as good at differentiating affected from control horses as images obtained between 2 to 4 hours after injection.

Conclusion

A substantial number of horses with palmar foot pain have increased scintigraphic uptake within the navicular bone 1 to 4 hours after injection of 99mTc-MDP. Lateral view, bone-phase images are less sensitive than palmar view, bone-phase images in revealing navicular area uptake.

Clinical Relevance

A combination of lateral and palmar view scintigraphic images obtained between 1 and 4 hours after injection of 99mTc-MDP is a useful diagnostic aid in evaluating navicular bone involvement in horses with forelimb lameness isolated to the palmar aspect of the foot. (Am J Vet Res 1996;57:415–421)
Local distribution of mepivacaine after distal interphalangeal joint injection in horses
Authors: Keegan Kevin G. , Wilson David A. , Kreeger John M. , Ellersieck Mark R. , Kuo Kenneth C. , Li Zhaolin
Published: January 2024

Objective

To evaluate the distribution of mepivacaine hydrochloride after distal interphalangeal (DIP) joint injection in horses.

Design

Prospective, uncontrolled study.

Animals

10 adult horses.

Procedure

30 minutes before euthanasia, 8 ml of 2% mepivacaine hydrochloride was injected into the dorsal pouch of a forelimb DIP joint. Synovial tissue from the DIP joint and podotrochlear (navicular) bursa and bone tissue from the medullary cavity of the distal sesamoid (navicular) bone were taken from both forelimbs immediately after death. All synovial and bone specimens were analyzed for tissue concentration of mepivacaine by high-performance liquid chromatography. Synovial tissue and bone specimen concentrations from the injected forelimb were compared with corresponding specimens from the noninjected forelimb. All synovial tissue and bone specimen concentrations were compared with an estimated effective tissue concentration of mepivacaine (0.3 µg/mg) for local anesthesia.

Results

Specimen concentrations of mepivacaine from the injected forelimb were significantly greater (P < 0.05) than those in the corresponding tissues of the contralateral noninjected forelimb. All DIP joint and navicular bursa synovial tissue specimens from the injected forelimb had greater than the estimated effective tissue concentration of mepivacaine for local anesthesia. Of the 10 navicular bone specimens from the injected forelimb, 4 were higher and 2 were within 20% of the estimated effective tissue concentration of mepivacaine for local anesthesia.

Conclusions

Mepivacaine hydrochloride deposited into the DIP joint should anesthetize pain arising from navicular bursa synovia and may decrease pain arising from the medullary cavity of the navicular bone.

Clinical Relevance

DIP joint injection of mepivacaine hydrochloride is not specific for DIP joint pain. (Am J Vet Res 1996;57:422–426)
Salmonella enteritidis in eggs, cloacal swab specimens, and internal organs of experimentally infected White Leghorn chickens
Authors: Bichler Lois A. , Nagaraja Kakambi V. , Halvorson David A.
Published: January 2024

Objective

To investigate prevalence of Salmonella enteritidis-positive eggs, excretion of the organism in fecal droppings, and infection of internal organs after oral inoculation of White Leghorn hens with S enteritidis phage type 8.

Animals

30 White Leghorn laying hens.

Procedure

At 25 weeks of age, hens were each inoculated orally with 1010 colony-forming units of S enteritidis, then were observed for 8 weeks.

Results

Salmonella enteritidis Y-8P2 did not cause any clinical signs of disease or decrease in egg production. However, at 1 week after inoculation, 63.9% of the eggs collected from inoculated hens were culture positive for S enteritidis. The organism was isolated from the shell washings, egg shells, yolk, and albumen. A total of 592 eggs from S enteritidis-inoculated hens were examined. Of these eggs, 157 (26.5%) were positive for S enteritidis on external shell washings alone, 17 (2.9%) were positive for S enteritidis internally, and 44 (7.4%) were positive for S enteritidis externally and internally. The percentage of culture-positive eggs gradually decreased between postinoculation weeks 2 and 5, then gradually increased to a high of 76% at week 8. At 3, 7, and 10 days after S enteritidis inoculation, cloacal swab specimens from 3 hens were positive for S enteritidis. Salmonella enteritidis was recovered from ovary, oviduct, liver, and cecal junction from S enteritidis-inoculated hens.

Conclusions

Our results indicated that birds infected with this isolate produced S enteritidis-positive eggs at high frequencies initially, that decreased over time. When S enteritidis antibody began to decrease, reaching geometric mean titer ≤ 40, the frequency of S enteritidis-positive eggs increased. (Am J Vet Res 1996;57:489–495)
Evaluation of injections of collagenase and Oxytetracycline via the umbilical artery as treatment for retained placenta in cattle
Authors: Fecteau Kellie A. , Eiler Hugo
Published: January 2024

Objectives

To test whether Oxytetracycline inactivates collagenase when combined as a potential treatment for retained fetal membranes in cattle and to determine whether Oxytetracycline passes to blood from fetal membranes after intraplacental injection.

Design

Prospective, controlled study.

Sample Population

288 placentomes from 12 cows in their third trimester of pregnancy and 4 cows at term pregnancy.

Procedure

8 experimental groups were established: saline control, collagenase, collagenase plus Oxytetracycline at 3 dosages, and Oxytetracycline at 3 dosages. Placentomes were infused through an umbilical vessel with the test solutions and incubated at 39 C for 4 hours. Immediately after incubation, the force needed to detach cotyledons from caruncles was measured by a manometry technique. Cotyledon-caruncle interface fluids were analyzed for hydroxyproline (collagen breakdown) and total protein contents. A combination of collagenase and Oxytetracycline was injected via umbilical arteries of cows undergoing cesarean section and in cows with retained fetal membranes after natural delivery. Antibiotic residue in blood was determined by the Bacillus stearothermophilus disk assay.

Results

There were no significant differences among collagenase and collagenase plus Oxytetracycline groups in the amount of pressure needed to separate cotyledon from caruncle, amount of hydroxyproline released, and amount of total protein broken down. The 4 cows tested negative for Oxytetracycline in the blood.

Clinical Relevance

Oxytetracycline and collagenase may be a potential combination treatment for retained fetal membranes in cattle. In addition, the lack of antibiotic residue detection in blood may be of regulatory relevance. (Am J Vet Res 1996;57:522–525)
Efficacy of florfenicol for treatment of clinical and subclinical bovine mastitis
Authors: Wilson David J. , Sears Philip M. , Gonzalez Ruben N. , Smith Brenda S. , Schulte Hal F. , Bennett Gary J. , Das Helena H. , Johnson Carl K.
Published: January 2024

Objective

To evaluate efficacy of florfenicol treatment for bovine mastitis caused by Streptococcus agalactiae, Staphylococcus aureus, nonagalactiae streptococci, coagulase-negative staphylococci, Escherichia coli, Klebsiella sp, and others.

Design

Double blind study with cases randomly assigned to 1 of 2 treatment groups.

Sample Population

861 cows/10 commercial dairy farms.

Procedures

Experimental (750 mg of florfenicol) or control (200 mg of cloxacillin) treatment was administered by intramammary infusion every 12 hours for 3 treatments to all cases. Treatments were randomly assigned, identified only by numerical labels. To retain blinding, the longer withdrawal time was adhered to for all cases. Cases remained in the study only if there was no other treatment. Quarter samples were recultured 14, 21, and 28 days later. If all samples after day 1 were culture negative, the case was defined as cured. If only 1 of the follow-up results was positive, the case was considered cured if the day-28 somatic cell count was < 300,000/ml. Failure of treatment was defined as 2 or more culture-positive follow-up samples.

Results

Florfenicol and cloxacillin did not differ significantly in efficacy versus clinical (n = 85) or subclinical (n = 71) bovine mastitis, or for any etiologic agent (χ2). Overall cure rates for mastitis were: Str agalactiae, 5 of 8 (63%); Sta aureus, 5 of 54 (9%); Streptococcus sp, 16 of 35 (46%); Staphylococcus sp, 7 of 33 (21 %); E coli, 5 of 11 (46%); Klebsiella sp, 3 of 6 (50%); others, 1 of 9 (11%); and all cases, 42 of 156 (27%).

Conclusions

Florfenicol did not offer any advantage over cloxacillin in efficacy against bovine mastitis. Overall cure rates were low. As with most mastitis treatment regimens, poor efficacy may be partly attributable to the short duration of treatment. (Am J Vet Res 1996;57:526–528)
Anesthesia induced in pigs by use of a combination of medetomidine, butorphanol, and ketamine and its reversal by administration of atipamezole
Authors: Sakaguchi Minoru , Nishimura Ryohei , Sasaki Nobuo , Ishiguro Toshikazu , Tamura Hiroshi , Takeuchi Akira
Published: January 2024

Objective

To develop an IM administrable anesthetic combination for pigs.

Design

Use of a combination of atropine, medetomidine, butorphanol, and ketamine (MB-K) was evaluated as an anesthetic regimen and compared with that of a combination of atropine, xylazine, butorphanol, and ketamine (XB-K). Cardiorespiratory effects of MB-K combination and use of atipamezole as a means of reversing anesthesia induced by MB-K were examined.

Animals

18 castrated, mixed-breed, specific-pathogen- free pigs, aged 8 to 15 (mean, 12.1) weeks and weighing 14.5 to 26.0 (mean, 19.6) kg, were studied.

Procedure

Dosages of drugs used in this study were atropine, 25 µg/kg of body weight; medetomidine 80 µg/ kg; xylazine, 2 mg/kg; butorphanol, 200 µg/kg; ketamine, 10 mg/kg; and atipamezole, 240 µg/kg.

Results

MB-K combination proved to be more effective than XB-K combination as an anesthetic combination. After quick and smooth induction by IM administration, MB-K-induced anesthesia was sustained for 98.8 ± 22.5 minutes (mean ± SD, 47.4 ± 16.5 minutes by XB-K) with accompanying muscular relaxation (91 ± 18 minutes) and loss of pedal (82 ± 24 minutes) and laryngeal (75 ± 19 minutes) reflexes. Loss of these reflexes was of significantly longer duration than the loss induced by XB-K, enabled tracheal intubation, and, thus, supported major surgery for at least 30 minutes after induction. Recovery from MB-K-mduced anesthesia was smooth. MB-K combination had a slight stimulative effect on cardiovascular status, and a significant depressant effect on blood gas and acid-base status, but these effects were within biologically acceptable limits. Oxygen consumption of pigs under MB-K-induced anesthesia decreased significantly. MB-K-induced anesthesia could be effectively and quickly reversed by IM or IV administration of atipamezole.

Conclusions

The combination of medetomidine, butorphanol, and ketamine induces excellent surgical anesthesia in pigs, and results in moderate cardiorespiratory effects. A great advantage of the anesthetic regimen is that it can be effectively and quickly reversed by atipamezole.

Clinical Relevance

Medetomidine, butorphanol, and ketamine-induced anesthesia is available for short-term major surgery in pigs. (Am J Vet Res 1996;57:529–534)
Quantitative investigation of population persistence and recurrent outbreaks of bovine respiratory syncytial virus on dairy farms
Authors: De Jong M. C. M. , van der Poel W. H. M. , Kramps J. A. , Brand A. , van Oirschot J. T.
Published: January 2024

Objective

To determine if transmission of virus among seropositive cattle is a plausible mechanism for the permanent presence of bovine respiratory syncytial virus (BRSV) in dairy herds, and how likely, with that scenario for persistence, there will be only 1 clinical outbreak of BRSV per year.

Design

Build a stochastic model, parameter estimation from serologic data on BRSV, and interpret the estimated parameter values from the model analysis.

Sample Population

Monthly data on the prevalence of antibodies directed against BRSV in sera from all cattle in 6 dairy herds.

Procedure

Parameter estimation applying general linear models, model analysis using calculation of the reproduction ratio for simplified models, and Monte-Carlo simulation for the whole model.

Results

Persistence of BRSV by transmission among seropositive cattle given estimated parameter values would be accompanied by frequent extinctions (once every 1 to 50 years) and long infectious periods in seropositive cattle (100 days). Moreover, in the model, a single clinical outbreak among seronegative cattle only occurred with external forcing.

Conclusions

From these data, transmission among seropositive cattle is not a plausible mechanism for persistence of BRSV in dairy herds. (Am J Vet Res 1996; 57:628–633)
Haptoglobin response to clinical respiratory tract disease in feedlot cattle
Authors: Wittum T. E. , Young C. R. , Stanker L. H. , Griffin D. D. , Perino L. J. , Littledike E. T.
Published: January 2024

Objective

To quantify haptoglobin response to respiratory tract disease in feedlot cattle, and to investigate its ability to predict disease outcome and response to antibiotic treatment.

Design

Randomized clinical trial.

Animals

60 feedlot calves with clinical respiratory tract disease.

Procedure

Calves were randomly assigned to receive a standard antibiotic treatment regimen (TRT), or to observation pens without antibiotic treatment. Serum haptoglobin concentration was measured at initial and final examinations. Calves were examined for presence of gross pulmonary lesions at slaughter.

Results

Mean ± SD serum haptoglobin concentration at initial examination was 67 ± 108 mg/dl, with range of 0 to 508 mg/dl. Haptoglobin concentration at initial examination was similar for the TRT group and the group that did not receive antibiotic treatment, but at final examination, TRT-group calves had lower (P < 0.01) mean values. Calves receiving antibiotic treatment had haptoglobin concentration at or near zero at final examination. Calves not receiving antibiotic treatment had only slightly lower mean haptoglobin concentration at final examination, compared with initial examination. Within treatment groups, haptoglobin concentration was similar for cases with different outcomes. Calves with gross pulmonary lesions a: slaughter had numerically higher, although statistically similar, haptoglobin concentrations at initial examination, compared with calves without lesions.

Conclusions

Feedlot cattle with clinical respiratory tract disease have a large and variable haptoglobin response. Antibiotic treatment resulted in lower serum haptoglobin values, although low values were not required for full clinical recovery.

Clinical Relevance

Serum haptoglobin concentration may be an indicator of response to antibiotic therapy, although it appears to be unrelated to case severity or need for treatment. (Am J Vet Res 1996; 57:646–649)
Disposition of transdermally administered fentanyl in dogs
Authors: Kyles Andrew E. , Papich Mark , Hardie Elizabeth M.
Published: January 2024

Objective

To evaluate the disposition of fentanyl after IV and transdermal administrations. The hypothesis was that transdermal administration of fentanyl would result in a measurable plasma opioid concentration.

Design

Each dog received 2 treatments in a randomized, crossover design.

Animals

6 clinically normal Beagles.

Procedure

2 treatments consisting of IV fentanyl (50 μg/kg of body weight) and transdermal fentanyl (50 μg/h) administrations. Plasma fentanyl concentrations were measured at fixed times, and pharmacokinetic values were calculated.

Results

Intravenous pharmacokinetics of fentanyl was similar to those previously described in dogs and provided the distribution and clearance data necessary to calculate the rate of absorption of the transdermally administered opioid. The transdermal fentanyl patch produced average steady-state concentrations of 1.6 ng/ml. The actual rate of delivery of transdermal fentanyl was 35.7 (range, 13.7 to 49.8) μg/h, which represented 71.48% (range, 27.45 to 99.56%) of the theoretical rate of delivery. The mean elimination half-life of fentanyl after patch removal was 1.39 hours.

Conclusions

Transdermally administered fentanyl resulted in fairly constant plasma concentrations, in the range generally considered to be analgesic, from 24 to 72 hours after application of the patch. The rate of drug delivery was less than expected, and there was substantial individual variation.

Clinical Relevance

Transdermally administered fentanyl has the potential to be a clinically useful analgesic regimen in dogs, and further evaluation of its analgesic actions and potential side effects is warranted. (Am J Vet Res 1996; 57:715–719)
Effects of U-74389G, a novel 21-aminosteroid, on small intestinal ischemia and reperfusion injury in horses
Authors: Vatistas Nicholas J. , Snyder Jack R. , Hildebrand Susan V. , Harmon Faye A. , Woliner Michael J. , Barry Sean J. , Nieto J. , Henry Pegeen , Enos L. Reed , Magliano David , Brown Scott A. , Drake Christiana
Published: January 2024

Objective

To determine the effects of the 21-amino-steroid, U-74389G, on reperfusion of the equine jejunum, using total (TVO) and partial (PVO) vascular occlusion during the ischemic period.

Design

TVO: 16 healthy horses were randomly allotted to 3 groups—4 horses received the vehicle alone, 6 horses received a low dosage (3 mg/kg of body weight), and 6 horses a high dosage (10 mg/kg) of U-74389G. PVO: 10 healthy horses were randomly allotted to 2 groups—5 horses received the vehicle alone, and 5 horses received the low dosage (3 mg/kg) of U-74389G.

Procedure

TVO was induced for 1 hour followed by 2 hours of reperfusion. During PVO, blood flow was reduced to 20% of baseline for 2 hours, followed by 2 hours of reperfusion.

For both models, either the vehicle alone or the drug was given 15 minutes prior to reperfusion. Samples were obtained before, during, and after ischemia for determination of myeloperoxidase (MPO) activity, malondealdehyde (MDA) concentration, concentration of conjugated dienes (PVO experiment only), and morphometric analysis.

Results

TVO: tissue concentration of MDA and MPO activity were not altered in any group by ischemia or reperfusion. During ischemia, mucosal volume and surface area were reduced. After reperfusion, no further reduction occurred. After initial decrease in submucosal volume during ischemia, there was a significant increase after reperfusion in the vehicle-only group (P < 0.05). PVO: there were no alterations in the concentration of either MDA or conjugated dienes. There was a significant increase in the activity of MPO during ischemia and reperfusion (P< 0.05). These effects were similar for the vehicle-only and drug groups. During ischemia, there was a significant decrease in mucosal surface area and volume (P< 0.05), that was continued during reperfusion for the vehicle-only group (P< 0.05). Submucosal volume increased during reperfusion (P< 0.05). Serosal volume was increased during ischemia and reperfusion.

Conclusions and Clinical Relevance

Reduced blood flow during ischemia (PVO group) caused continued loss in mucosal volume and surface area during reperfusion. At the dosage given, the 21-aminosteroid, U-74389G, was not effective in preventing continued reduction in mucosal volume and surface area after restoration of blood supply in the horses subjected to reduced blood flow. (Am J Vet Res 1996; 57:762–770)