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Efficacy of netobimin against Muellerius capillaris and resistant strain of digestive tract strongyles in dairy goats
1991
Cabaret, J.
The efficacy of netobimin against digestive tract strongyles and the small lungworm Muellerius capillaris was tested in a dairy goat herd. The drenches were given orally at the rate of 20 mg/kg of body weight once, 10 mg/kg on 2 successive days, or 7.5 mg/kg on 3 successive days. Fecal egg counts and larval counts were done 8 days before and on the day of drenching; further counts were performed on postdrenching days 8 and 18. Two goats were necropsied, 1 on postdrenching day 5 and 1 on day 10 in the group treated on 3 successive days. The fecal egg counts were reduced by 44 to 79% depending on dosage on postdrenching day 18; the remaining worms were Trichostrongylus colubriformis. The larval counts of M capillaris were reduced by 72 to 92%, depending on dose. The reduction was significant in all the treated groups, compared with that in the control group. The use of netobimin at the dosage of 10 mg/kg given on 2 successive days or 7.5 mg/kg given on 3 successive days might be recommended to treat goats infected with Muellerius spp and digestive tract strongyles.
Показать больше [+] Меньше [-]Epizootiology of helminth parasitism in a beef cow/calf herd in Minnesota
1991
Stromberg, B.E. | Schlotthauer, J.C. | Haggard, D.L. | Vatthauer, R.J. | Hanke, H. | Myers, G.H.
To test the effect of a parasite control program for cattle, 2 groups of similar composition were grazed on separate, but equivalent, improved pastures. Cattle in 1 group were treated with fenbendazole at 5.0 mg/kg of body weight at the time they were turned out on pasture in the spring and again at midsummer, when the cattle were moved to a new pasture. The control group was not treated. Parasite egg counts were significantly (P < 0.04) lower in the treated group. Trichostrongyle-type eggs were the most prevalent throughout the, year, except in the month of May, when Strongyloides papillosus eggs were predominant. The number of worms recovered from tracer calves was lower for those on pastures where the treated group grazed than for those on- the control group's pasture. The most consistently recovered parasite was Ostertagia ostertagi, and hypobiosis was observed.
Показать больше [+] Меньше [-]Antibody response to glycoprotein I in maternally immune pigs exposed to a mildly virulent strain of pseudorabies virus
1991
Oirschot, J.T. van | Daus, F. | Kimman, T.G. | Zaane, D. van
To study the antibody response to glycoprotein I (gI) of pseudorabies virus (PRV) in maternally immune pigs, 3 groups of 6 pigs were given low doses of the mildly virulent Sterksel strain of PRV at 3 and 11 weeks of age. Group A consisted of seronegative pigs; groups B and C consisted of pigs with maternal antibodies deficient of antibodies to gI. At 3 weeks of age, 3 pigs of each group were inoculated intranasally with 10(2.5) plaque-forming units (groups A and B), or with 10(3.5) plaque-forming units (group C) of PRV. The 3 other pigs in each group were contact-exposed to the inoculated pigs. In group A, 4 of 6 pigs shed virus and all developed antibodies to gI of PRV and produced PRV-specific IgM and virus-neutralizing antibodies. In groups B and C, 10 pigs shed virus and all developed low and inconsistent titers of gI antibodies, whereas only 3 pigs produced PRV-IgM antibodies with low titers. Thus, after PRV infection of pigs with high concentrations of maternal antibodies deficient of gI antibodies, the antibody responses to PRV were severely inhibited. The pigs were reinoculated with 10(3) plaque-forming units of the same virus 8 weeks after the first inoculation. The pigs in group A did not respond at all, as they were immune. The pigs in groups B and C shed considerable amounts of virus. Three pigs had a clear secondary antibody response to gI, whereas the others developed an early to normal antibody response to gI. None of the pigs mounted a secondary neutralizing antibody response to PRV. We concluded that inoculation of pigs having high titers of gI-deficient maternal antibodies with low doses of a mildly virulent PRV, induced low to undetectable concentrations of antibodies to gI.
Показать больше [+] Меньше [-]Platelet function, antithrombin-III activity, and fibrinogen concentration in heartworm-infected and heartworm-negative dogs treated with thiacetarsamide
1991
Platelet aggregation and release, platelet number, mean platelet volume, antithrombin-III activity, and fibrinogen concentration were evaluated in heartworm-negative and heartworm-infected dogs at baseline and on days 3, 10, and 21 after treatment with thiacetarsamide. Platelet reactivity was enhanced in a group of dogs naturally infected with Dirofilaria immitis, compared with 2 groups of heartworm-negative dogs, but platelet reactivity was not further enhanced after treatment with thiacetarsamide. A significant decrease in antithrombin-III activity was detected 21 days after treatment. The platelets from a group of laboratory Beagles implanted with 50 adult D immitis displayed enhanced reactivity 6 months after implantation, but by 18 months, platelet reactivity had returned to near, or less than, baseline. Platelet reactivity was enhanced after thiacetarsamide treatment in this group. Thiacetarsamide-associated changes were not observed in platelet number or size; antithrombin-III activity decreased, but the change was not significant. Fibrinogen concentration was increased significantly (P < 0.05) on day 10. Enhanced adenosine diphosphate (ADP)-induced platelet aggregation was observed on days 3, 10, and 21 after treatment in heartworm-negative dogs. This change was not observed in 6 control Beagles not treated with thiacetarsamide. Although antithrombin-III activity was decreased on day 3 and fibrinogen concentration was increased on day 10, paralleling changes observed in the heartworm-infected dogs, the changes were not statistically significant. In this study, thiacetarsamide was procoagulatory in heartworm-negative dogs and may be an important contributing factor to the thromboembolism observed with adulticidal therapy.
Показать больше [+] Меньше [-]Cutaneous laser-Doppler velocimetry in nine animal species
1991
The assessment of cutaneous microcirculation by laser-Doppler velocimetry (LDV) has been primarily limited to human studies. The purpose of this investigation was to establish normal values in various species and anatomic sites for blood flow, velocity, and volume as determined by LDV. Microcirculation was measured with a laser-Doppler velocimeter in 54 animals, 6 healthy animals from each of 9 species. The standard sites used were the buttocks, convex surface of the ear, metacarpal pad, humeroscapular junction, thoracolumbar junction, ventral portion of the abdomen, dorsal metacarpus (hooved animals), and ventral surface of the tail (horse). Significant differences in blood flow, velocity, and volume were measured between species and sites within species. The ventral portion of the abdomen consistently had the highest relative blood flow across all species except the monkey. Measurements in the canine metacarpal pad had a high SD, possibly indicating the stratum corneum and epidermis to be too thick for LDV. Our findings provide baseline data in several species, with application of LDV in comparative dermatologic research.
Показать больше [+] Меньше [-]Multivariable prediction model for the need for surgery in horses with colic
1991
Reeves, M.J. | Curtis, C.R. | Salmān, Muḥammad | Stashak, T.R. | Reif, J.S.
A survey of 1,965 equine colic cases was conducted from August 1985 to July 1986 at 10 equine referral centers located throughout the United States. The purpose of this study was to develop and validate a multivariable model for the need for surgery. Two-thirds of the cases were randomly selected for model development (1,336), whereas the remaining cases (629) were used only for subsequent validation of the model. If a lesion requiring surgical correction was found at either surgery or necropsy, the case for the horse was classified as surgical, otherwise the case was classified as medical. Only variables that were significant (P < 0.05) in an initial bivariable screening procedure were considered in the model development. Because of the large number of missing values in the data set, only variables for which there were < 400 missing values were considered in the multivariable analysis. A multivariable logistic regression model was constructed by use of a stepwise algorithm. The model used 640 cases and included variables: rectal findings, signs of abdominal pain, peripheral pulse strength, and abdominal sounds. The likelihood ratio for surgery was calculated for each horse in the validation data set, using the logistic regression equation. Using Bayes theorem, the posttest probability was calculated, using the likelihood ratio as the test odds and the prevalence of surgery cases (at each institution) as an estimate of the pretest odds. A Hosmer-Lemeshow goodness-of-fit X2 statistic indicated that the model fit the validation data set poorly, as demonstrated by the large X2 value of 26.7 (P < 0.001). However, when the expected proportion of surgical cases was compared with the observed proportion of surgical cases in each of 10 increments of risk, the model's performance appeared satisfactory.
Показать больше [+] Меньше [-]Detection of anti-equine neutrophil antibody by use of flow cytometry
1991
Jain, N.C. | Stott, J.L. | Vegad, J.L. | Dhawedkar, R.G.
Flow cytometric and conventional fluorescence microscopic methods were compared to detect heterologous (rabbit) neutrophil antibody bound to equine neutrophils. Unfixed and paraformaldehyde-fixed neutrophils were treated with normal rabbit serum or various dilutions of an antineutrophil serum. The cells were then reacted with fluorescein conjugates of goat anti-rabbit IgG, staphylococcal protein A, and streptococcal protein G. Antibody binding was evaluated by use of fluorescence microscopy and flow cytometry. Unfixed neutrophils treated with normal rabbit serum did not fluoresce, whereas many of the fixed neutrophils had distinct cytoplasmic and some membranous (nonspecific) fluorescence. Unfixed cells treated with the antiserum had localized areas (capping) of intense membrane fluorescence, whereas fixed cells had bright uniform membranous fluorescence. The intensity of specific fluorescence varied with the antiserum dilution and the conjugate. On flow cytometry, over 80% of unfixed cells treated with antiserum dilutions up to 1:1,024, 1:2,048, and 1:256 fluoresced, respectively, with anti-IgG, protein-G, and protein-A conjugates. Fixed cells generally had similar percentages of fluorescent cells, but at a higher (1-step) antiserum dilution. It was concluded that flow cytometry is more sensitive than conventional fluorescence microscopy to detect antibodies associated with equine neutrophils.
Показать больше [+] Меньше [-]Prevalence of pigment gallstones in sheep
1991
Cavallini, A. | Messa, C. | Mangini, V. | Linsalata, M. | Guerra, V. | Misciagna, G. | Di Leo, A.
In a survey of 666 sheep at a slaughterhouse, gallstones (concretions with a diameter greater than or equal to 1 mm) were found in the gallbladder of 50 sheep (7.5%), sludge (concretions with a diameter < 1 mm) was found in 9 sheep (1.4%), and sludge plus gallstones were found in 7 sheep (1.1%). Gallstones and sludge were associated, and were more frequent in lambs and females, compared with adults and males. Qualitative analysis of the stones revealed all to be pigment (bilirubin) stones. There was a statistically significant increase of biliary bilirubin (total and indirect quota) only in sheep with gallstones plus sludge, compared with control sheep without sludge or gallstones. Concentrations of bilirubin, cholesterol, phospholipids, total and single bile aids, and total and ionized calcium were similar in the bile of sheep with gallstones, sludge, or both and control sheep. Bacteriologic analysis of the bile in 10 sheep with gallstones and 10 controls revealed bacteria in 50% of the first group and in 75% of the second group (Escherichia coli in all sheep and Salmonella spp also in 1 sheep with gallstones). These findings confirm our earlier findings of a high prevalence of black pigment gallstones in sheep. On that basis, we suggest that gallstones are associated with high total bilirubin concentration in the bile, and deconjugating bacteria are common in the biliary tract of these animals.
Показать больше [+] Меньше [-]Changes in phospholipids of alveolar lining material in calves after aerosol exposure to bovine herpesvirus-1 or parainfluenza-3 virus
1991
Engen, R.L. | Brown, T.T. Jr
Pulmonary lavage samples were collected from 90- to 130-day-old calves before and 6 days after aerosol inoculation with bovine herpesvirus-1 (BHV-1) or parainfluenza-3 (PI3) virus. Alveolar lining material was separated from lavage fluids by high-speed centrifugation and phospholipids were extracted from alveolar lining material and analyzed by high-performance liquid chromatography. Phosphatidylcholine and phosphatidylethanolamine were 74.2 +/- 6.5% and 13.3 +/- 2.8%, respectively, of the total phospholipid content in the surfactant obtained from calves before virus inoculation. Other phospholipids were represented by substantially lower percentages. Infection with either of the 2 viruses caused a significant (P < 0.05) decrease in the percentage of phosphatidylcholine to 66.0 +/- 8.0% and 65.1 +/- 10.8% in the calves inoculated with BHV-1 and PI3 virus, respectively. A significant (P < 0.05) increase in the percentage of phosphatidylethanolamine to 18.1 +/- 2.2% and 17.8 +/- 4.5% developed in calves inoculated with BHV-1 and PI3 virus, respectively. Infection with BHV-1 also induced an increase (not significant) in the percentage of phosphatidylinositol from 5.5 +/- 2.8% to 7.8 +/- 2.2%. A similar, but not significant, increase in the percentage of phosphatidylinositol was also seen in the calves inoculated with PI3 virus. Less substantial changes in the percentage of other phospholipids were detected after virus infection.
Показать больше [+] Меньше [-]Comparison of effects of cimetidine and omeprazole on mechanically created gastric ulceration an on aspirin-induced gastritis in dogs
1991
Jenkins, C.C. | DeNovo, R.C. | Patton, C.S. | Bright, R.M. | Rohrbach, B.W.
A double-blind study was conducted to compare gastric ulcer healing time in nontreated dogs with that in dogs treated with either cimetidine or omeprazole. Single ulcers were created in the gastric antrum by use of a suction biopsy capsule. Each dog was given 25 mg of aspirin/kg of body weight orally for 20 days after ulcer induction. Five control dogs were given aspirin only (no anti-ulcer medication) during the 20-day study. Six dogs were given cimetidine at dosage of 10 mg/kg orally every 8 hours, and 6 dogs were given omeprazole orally at dosage of 2 micromole/kg (0.7 mg/kg) once daily. All dogs were examined endoscopically on days 5, 10, 15, and 20 and were given a score for the size of the mechanically created ulcer and a score for the degree of aspirin-induced gastritis. All dogs were euthanatized on day 21, and gastric lesions were examined histologically. Significant differences were not evident in ulcer healing scores or degree of aspirin-induced gastritis among treated and nontreated dogs on days 5, 10, 15, and 20. However, aspirin-induced gastritis was less severe in dogs of the omeprazole group than in dogs of the cimetidine or control group on each day observations were made. The effect of omeprazole given once daily was comparable with that of cimetidine given every 8 hours in lessening aspirin-induced gastritis.
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