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Effect of prostaglandin F2 alpha on adrenal-produced steroid hormones in cows
1989
Watson, Ed | Hinrichs, K.
Ovariectomized, nonlactating cows were treated with IM injections of either physiologic saline solution or prostaglandin F2 alpha. Plasma concentrations of cortisol increased significantly by 30 to 60 minutes after injection of prostaglandin F2 alpha, but there were no significant increases in plasma concentrations of estradiol, progesterone, or testosterone. After saline solution treatment, there were no increases in any of the hormones measured.
Show more [+] Less [-]Rapid decay of serum IgG recognizing gram-negative cell wall core antigens in neonatal calves
1989
Douglas, V.L. | Cullor, J.S. | Tyler, J.W. | Thurmond, M.C. | Bushnell, R.B.
Serum immunoglobulins of the IgG isotype recognizing common gram-negative cell core epitopes were serially measured, using a direct ELISA, on samples obtained from 20 neonatal Holstein calves. An R-mutant Escherichia coli (strain J5) was used as a plate antigen in this assay. Total serum IgG concentration was measured using radial immunodiffusion. Half-lives of core antigen-specific IgG (7.56 days) and total serum IgG (22.66 days) were dramatically different (P less than 0.0005). This may be an indication of cross-reactive consumption of core antigen-specific immunoglobulins.
Show more [+] Less [-]Effects of inoculations with Eimeria zuernii on young calves treated with decoquinate or narasin with or without dexamethasone
1989
Fitzgerald, P.R. | Mansfield, M.E.
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 decoquinated 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.
Show more [+] Less [-]Neonatal survival in swine: effects of low birth weight and clinical disease
1989
Gardner, I.A. | Hird, D.W. | Franti, C.E.
Data were collected for 3,636 full-term pigs born in a commercial swine herd to determine the effects of birth weight and clinical disease on survival during the first 3 weeks of life. Logistic regression models were constructed for 7-day survival for all live-born pigs, and for 21-day survival for pigs surviving the first week of life. Estimates of birth weight and disease effects were adjusted simultaneously for other risk factors including litter size, parity, and within-litter variation in birth weight. The 7-day survival model indicated that survival odds improved significantly with increasing birth weight. Maximal survival, relative to pigs weighing less than 601 g at birth, was evident in pigs weighing greater than 2 kg atbirth (odds ratio [OR] = 349). Diarrhea (OR = 2.7) and splayed limbs (splay leg; OR = 37.3) significantly (P less than 0.05) reduced 7-day survival. Models of 21-day survival indicated a smaller, but still significant, effect of birth weight on survival. Adjusted survival odds for pigs in the heaviest weight group (greater than 2 kg) were 20.1 times higher than pigs weighing less than 801 g. Diarrhea (OR = 2.7) and lameness (OR = 2.6, 2 limbs) significantly (P less than 0.05) decreased 21-day survival.
Show more [+] Less [-]In vitro ultrasonographic appearance of the normal and verminous equine aorta, cranial mesenteric artery, and its branches
1989
Wallace, K.D. | Selcer, B.A. | Tyler, D.E. | Brown, J.
Ninety-one equine aortic and cranial mesenteric arterial segments were evaluated ultrasonographically in a water bath. On the basis of pathologic evidence of verminous arteritis, arterial segments were classified into 4 categories, and the ultrasonographic characteristics of each group were evaluated. Normal arteries (class 1) were ultrasonographically characterized by a smooth luminal surface layer and uniform wall thickness and echogenicity. Arteries with only histopathologic evidence of verminous arteritis (class 2) were ultrasonographically characterized by a smooth luminal surface layer, uniform thickness, uniform echogenicity, and the presence of a hyperechoic luminal layer. Arteries with both gross and histopathologic evidence of verminous arterities (class 3) were characterized ultrasonographically by an irregular luminal surface layer, varying wall thickness, varying wall echogenicity, and the presence of a hyperechoic luminal layer. The ultrasonographic characteristics of arteries with luminal thrombosis (class 4) were an irregular luminal surface, varying wall thickness, and nonuniform echogenicity.
Show more [+] Less [-]Continuous electromyographic recordings of pharyngeal muscle activity in normal and previously denervated muscles in dogs
1989
Venker-van Haagen, A.J. | Hartman, W. | Brom, W.E. van den | Wolvekamp, W.T.C.
Continous electromyographic recordings of pharyngeal muscle activity were made in 5 clinically normal control dogs and in 7 dogs 3 years after partial denervation of the pharyngeal muscles. Electromyographic recordings were made of the sequence of actions of each muscle and of the combined muscle activity, at rest and during swallowing of food. During 30-second periods, the recordings were digitalized and stored on diskette for further analysis. All control dogs had a distinct pattern of muscle activity during swallowing, the onset being in a constant order (hyopharyngeal, thyropharyngeal, and cricopharyngeal) and bilaterally synchronous. While eating, each dog had about 5 to 12 short periods of synchronous activity in each muscle, between the swallowing actions. During the resting period, there were longer periods of activity, which were synchronous with respiration. In each denervated dog, there were normal and irregular swallowing actions. Swallowing activity was recognized, but the sequence of hyopharyngeal, thyropharyngeal, and cricopharyngeal muscle activity was irregular and different from that in control dogs. Partial denervation of the pharyngeal muscles does not seriously impair motor activity of the muscles, but does alter the sequence of activity in the pharyngeal muscles during swallowing.
Show more [+] Less [-]Decreased protein kinase C activity in fatty liver from cattle
1989
Katoh, N. | Kimura, K.
Protein kinase (PK) C activity in the liver of cattle with fatty liver syndrome was evaluated and compared with that in liver of healthy cattle. The PKC activities in cytosolic and particulate fractions were reduced in fatty livers, compared with those in livers from healthy cattle. The decrease of PKC activity was more distinct in cytosolic (P = 0.0016) than particulate (P = 0.069) fractions. Protein kinase activities other than PKC were not substantially changed. Seemingly, PKC was involved in the pathogenesis of fatty liver syndrome in cattle.
Show more [+] Less [-]Nuclear scintigraphic assessment of liver size in clinically normal dogs
1989
Godshalk, C.P. | Twardock, A.R. | Kneller, S.K.
Measurement of liver size was made on nuclear scintigraphic images obtained from 16 clinically normal, anesthetized dogs in ventral, dorsal, right and left lateral, and left dorsal oblique positions after administration of technetium 99m-sulfur colloid. Linear measurements of liver length and width were make from each scintiscan, and liver surface area was determined by setting a region of interest manually and by use of a computer count of pixels above a minimal intensity (threshold method). All linear measurements had a statistically significant (P less than 0.05) correlation with liver and body weight, with the exception of the measurements of liver width made on dogs in dorsal and left lateral dorsal oblique positions. The highest correlation (r = 0.89) between the scintigraphic measurements and liver weight was the multiplication of measurements of liver width and length from the right lateral view. Although all area determinations were significantly (P less than 0.05) correlated with liver and body weight, for most views, the manual method of determining the region of interest had a slightly better correlation with the liver weight than did the threshold method.
Show more [+] Less [-]Effect of Pasteurella haemolytica (A1) capsular polysaccharide on sheep lung in vivo and on pulmonary surfactant in vitro
1989
Brogden, K.A. | Adlam, C. | Lehmkuhl, H.D. | Cutlip, R.C. | Knights, J.M. | Engen, R.L.
Capsular polysaccharide (CP) of Pasteurella haemolytica (type A1) was first deposited by fiberoptic bronchoscopy in the lungs of sheep to examine lesions and changes in bronchoalveolar lavage cell populations and, later, was mixed with pulmonary surfactant to investigate alterations in physical properties or surface tension. At 22 hours after deposition, minimal lesions were seen in the lungs only at and contiguous to the site of CP deposition in 2 of 4 sheep. Microscopically, alveoli and interlobular septa were filled with edema fluid. Terminal airways and alveoli contained a moderate amount of neutrophils that varied between sheep. Significant differences in number or type of bronchoalveolar lavage cells were not observed in the weekly lavages between each group or among sheep within each group, either before or after deposition of CP or physiologic saline solution. After 6 hours of incubation at 37 C, CP-surfactant mixtures were examined with a surface tensiometer and centrifuged in sucrose gradients. The CP bound to surfactant, resulting in formation of a precipitate with a surface tension of 31.6 +/- 0.1 dynes/cm and a density of 1.07 to 1.08 g/ml. Lipopolysaccharide of P haemolytica, used as a control, also bound to surfactant, resulting in a complex with a surface tension of 57.7 +/- 0.4 dynes/cm and a density of 1.06 to 1.10 g/ml. Surfactant alone had a surface tension of 32.6 +/- 0.2 dynes/cm and density of 1.05 to 1.06 g/ml. The CP appears by itself not to be a direct major factor in the lung damage that develops in cases of pneumonic pasteurellosis. However, the precipitation of surfactant by CP may be a lectin reaction that would allow the attachment of the organism to the lining of the alveolus and become established during an infection.
Show more [+] Less [-]Influence of limb temperature on sensory nerve conduction velocity in horses
1989
Wheeler, S.J.
Sensory nerve conduction velocity was measured in the lateral palmar nerve of 8 horses. The limb temperature was manipulated by external means and monitored. Alterations in the nerve conduction velocity related to limb temperature variation were identified at both increased and decreased temperatures. These were quantified and a mean value of 2.15 +/- 0.2 m/s/degree Celsius was determined. The effect of altered limb temperature should be considered in nerve conduction velocity determinations.
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