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Normal blood supply to the canine mandible and mandibular teeth
1989
Roush, J.K. | Howard, P.E. | Wilson, J.W.
The normal blood supply to the canine mandible and mandibular teeth was determined by microangiography and correlated histology. Branches of the inferior alveolar artery supplied the cortical bone of the mandibular body. Vessels from the periosteal and endosteal surfaces supplied symphyseal cortical bone. Direct vascular anastomoses were not found to cross the fibrous mandibular symphysis. Blood supply to the mandibular teeth was via dental arteries derived from the inferior alveolar artery, with interdental and interradicular arteries supplying the alveolar bone and periodontal ligament.
اظهر المزيد [+] اقل [-]Echocardiographic assessment of cardiac chamber size and functional performance in swine
1989
Gwathmey, J.K. | Nakao, S. | Come, P.C. | Abelmann, W.H.
Nintey nonanesthetized 7- to 16-week-old pigs were studied, using 2-dimensional echocardiography that permits orientation of a targeted M-mode beam perpendicular to structures being studied and allows serial studies of the same cardiac regions. Normative data were obtained and included body weight and measurements of left atrial diameter, mitral valve excursion, aortic root diameter, left ventricular end-diastolic and end-systolic diameters, and left ventricular fractional shortening. A positive correlation was found between body weight and measurements of left atrial diameter, mitral valve excursion, aortic root diameter, left ventricular end-diastolic and end-systolic diameters, and fractional shortening. A correlation was found between body weight and age. Best-fit analysis resulted in all measurements fitting either a first- or second-degree polynomial.
اظهر المزيد [+] اقل [-]Inhibition of pregnancy in heifers, using a repositol formulation of melengestrol acetate
1989
Floyd, J.G. Jr | Ott, R.S. | Weigel, R.M. | Zinn, G.M. | Hixon, J.E.
Efficacy of a repositol formulation of melengestrol acetate (MGA) for inhibition of pregnancy was determined in one hundred 14- to 16-month-old beef heifers. Nonpregnant heifers were allocated on the basis of weight into 5 groups of 20 heifers each and were given 0, 30, 60, 90, or 120 mg of repositol MGA, SC, on day 0. Four bulls, determined to be satisfactory potential breeders, were pastured with the heifers from postinjection days (PID) 7 to 177. The day of gesation was estimated for each heifer by rectal palpation at PID 59, 91, 134, 177, and 225. Heifers not pregnant by PID 177 were assigned a day of conception of greater than 177. For heifers given 0, 30, 60, 90, and 120 mg of MGA, respectively, the percentage pregnant at PID 177 was 95, 95, 50, 15, and 15%, and the median day of estimated conception was PID 21, 87, 175, greater than 177, and greater than 177. Repositol MGA significantly (P less than 0.001) affected the distribution of conception times over all doses. Average daily gain (+/- SEM) for 178 days was 0.28 +/- 0.04 kg, 0.24 +/- 0.03 kg, 0.33 +/- 0.04 kg, 0.40 +/- 0.03 kg, and 0.35 +/- 0.03 kg for heifers given 0, 30, 60, 90, and 120 mg of MGA, respectively. Increased dose of repositol MGA was associated with increased average daily gain, but this effect was not apparent when days pregnant were taken into account. Repositol MGA was an effective contraceptive for pastured heifers and the duration of its effect was dose-dependent.
اظهر المزيد [+] اقل [-]Serum antibody response to carbohydrate antigens of Pasteurella haemolytica serotype 1: relation to experimentally induced bovine pneumonic pasteurellosis
1989
Confer, A.W. | Simons, K.R. | Panciera, R.J. | Mort, A.J. | Mosier, D.A.
The antibody responses to the capsular carbohydrate (CC) purified from Pasteurella haemolytica serotype 1 were determined by an ELISA using 135 sera from 6 calves vaccinated with phosphate-buffered saline solution, formalin-killed P haemolytica bacterins, live P haemolytica, or an extract of P haemolytica referred to as carbohydrate-protein subunit (CPS). Calves vaccinated with live P haemolytica, bacterins, or CPS developed serum antibodies to CC. Bacterins containing Freund incomplete adjuvant or Freund complete adjuvant induced higher antibody responses than did bacterins containing aluminum hydroxide. In 4 of 6 experiments, high antibody responses to CC were significantly (P less than 0.05) correlated with resistance to transthoracic challenge exposure with P haemolytica. When calves were challenge exposed with a dose of P haemolytica that was 4.5 times greater than the standard challenge exposure dose or when calves that had been vaccinated with CPS were challenge exposed, antibody responses did not significantly (P greater than 0.05) correlate with resistance to challenge exposure. The amount of serum antibodies to CPS increased significantly (P less than 0.05) when calves were vaccinated with live or killed P haemolytica or with CPS, compared with that in calves given saline solution. In 5 of 6 experiments, correlation between high antibody responses and resistance to challenge exposure was significant (P less than 0.05). The correlation between those variables was not significant (P less than 0.07) for CPS-vaccinated calves. In the ELISA, treatment of CPS with sodium m-periodate, to oxidize periodate-sensitive carbohydrate epitopes, failed to markedly alter the antibody response to CPS. However, the correlation between high antibody responses to periodate-treated CPS and resistance was significant (P less than 0.05) for all 6 experiments. In the ELISA, periodate treatment of CC, lipopolysaccharide, and CPS caused average reductions in antibody reactivity of 7.1%, 53.8%, and 34.5%, respectively. Preadsorption of sera with CC or lipopolysaccharide did not markedly reduce antibody reactivity with CPS. Preadsorption of sera with CC and reaction with periodate-treated and nontreated CPS indicatedthat for calves given phosphate-buffered saline solution vaccines, antibody reactivity was reduced 65.4%, whereas for those vaccinated with a bacterin with aluminum hydroxide, a bacterin with Freund incomplete adjuvant, or live P haemolytica, antibody reactivity was reduced 47.1%, 40.5%, and 25.0%, respectively. It was concluded that serum antibodies to CC are of some importance in resistance and that certain epitopes in CPS that are not sensitive to periodate are of importance in resistance to bovine pneumonic pasteurellosis. There are qualitative and quantitative differences among the serum antibody responses to carbohydrate epitopes for calves vaccinated with phosphate-buffered saline solution, bacterins, or live P haemolytica.
اظهر المزيد [+] اقل [-]Column chromatographic characterization of cytoplasmic proteins in Eimeria maxima oocysts from chickens
1989
Ainsworth, A.J. | Pote, L. | Haney, J. | Brown, J.
Cytoplasmic proteins from unsporulated and sporulated Eimeria maxima oocysts were analyzed by gel-filtration column chromatography. Unsporulated oocysts were characterized as having 3 major cytoplasmic proteins and sporulated oocysts as having 5 major cytoplasmic proteins. Molecular weights ranged from 5 X 10(3) to 1.4 X 10(6). Larger molecular weight proteins were detected in sporulated and unsporulated oocysts, but were associated more with sporocysts of sporulated oocysts.
اظهر المزيد [+] اقل [-]In vitro susceptibility of feline herpesvirus-1 to vidarabine, idoxuridine, trifluridine, acyclovir, or bromovinyldeoxyuridine
1989
Nasisse, M.P. | Guy, J.S. | Davidson, M.G. | Sussman, W. | Clercq, E. de
In vitro activities of 9-([2-hydroxyethoxy] methyl) guanine (acyclovir), (E)-5-(2-bromovinyl)-2'deoxyuridine, 9-beta-D-arabinofuranosyladenine (vidarabine), 5-iodo-2'-deoxyuridine (idoxuridine), and 5-trifluoromethyl-2'-deoxyuridine (trifluridine) were studied against 6 strains of feline herpesvirus-1. A significant difference was not detected among viral strains in their susceptibility to these compounds (P = 0.442). The relative potency of these compounds was trifluridine greater than greater than idoxuridine greater than virdarabine greater than bromovinyldeoxyuridine greater than greater than acyclovir. Concentrations of trifluridine and idoxuridine (0.67 and 6.8 micromole, respectively) required to reduce plaque numbers by 50%, compared with that of controls, were significantly lower (P less than 0.001) than were those of other compounds.
اظهر المزيد [+] اقل [-]Distribution of cholinergic and adrenergic nerve fibers in the lacrimal glands of dogs
1989
Powell, C.C. | Martin, C.L.
The distribution of postganglionic autonomic nerve fibers in the lacrimal gland and gland of the third eyelid of dogs was studied by use of histochemical techniques. Adrenergic nerve distribution was identified by use of the sucrose-potassium phosphate-glyoxylic acid technique. A loose network of adrenergic nerves was found throughout the interstitium around acini and blood vessels and in vessel walls. Acetylcholinesterase staining was used to identify cholinergic nerve fibers. A cholinergic distribution pattern around acini and blood vessels similar to the adrenergic pattern was found, although the cholinergic innervation appeared more dense than the adrenergic. In the gland of the third eyelid, mucus-secreting lobules and lipid-secreting lobules appeared to be equally innervated by parasympathetic fibers. These lobules could not be differentiated when the sucrose-potassium phosphate-glyoxylic acid technique was used. The techniques used in this study could not demonstrate whether direct contact was made by either cholinergic or adrenergic nerve fiber with secretory or myoepithelial cells. The presence of both nerve fiber types around acini suggests an interrelationship between the sympathetic and parasympathetic nervous system in lacrimal gland secretion in dogs.
اظهر المزيد [+] اقل [-]Influence of isoprinosine on lymphocyte function in virus-infected feeder pigs
1989
Flaming, K.P. | Blecha, F. | Fedorka-Cray, P.J. | Anderson, G.A.
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 (10(5) 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 less than 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 less than 0.05) on days 12 and 16, primarily caused by neutrophilia. Concanavalin A-stimulated lymphocyte proliferation was decreased (P less than 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 less than 0.02) in ISO-PRV pigs on day 8 of the experiment. Interleukin-2 concentrations, pooled over all sampling days, were decreased (P less than 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 prodcution in pigs, and that isoprinosine did not mitigate these effects.
اظهر المزيد [+] اقل [-]Kinematic analysis of cutting horses working a mechanical flag
1989
Clayton, H.M.
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 less than $35,000 in purse money; and group 2, composed of 7 highly successful or elite performers that had amassed greater than $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 less than 0.01), and were positioned closer to the flag during all stages of the trial (P less than 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%.
اظهر المزيد [+] اقل [-]Survival analysis for evaluation of corneal ulcer healing times in calves with naturally acquired infectious bovine keratoconjunctivitis
1989
Edmondson, A.J. | George, L.W. | Farver, T.B.
A clinical trial examining the efficacy of 2 drugs for treatment of a natural epizootic of infectious bovine keratoconjunctivitis was performed. The study was conducted in 103 grazing Hereford calves during the summer of 1985. The calves were prospectively and randomly assigned to 1 of 3 groups at the beginning of the study on June 17, and were examined 3 times weekly thereafter until the final observation on August 6. Calves in group 1 (n = 34) were not treated and were used as controls. Calves of group 2 (n = 34) with corneal ulcers were treated with a long-acting oxytetracycline formulation (OTC group). The parenteral treatment was repeated in 72 hours. Affected calves of group 3 (n = 35) were treated topically with furazolidone spray when they developed new corneal ulcers, or when existing lesions worsened during subsequent examination periods (NFZ group). Healing times of the corneal ulcers were reported in 3 ways: the combined times for ulcers present in both eyes of a calf simultaneously (method A), independent times of each ulcer on a calf (method B), and time of the first ulcer for each calf (method C). Censored healing times were examined as left censored (ulcer present at the beginning of the study), right censored (ulcer not healed at the end of the study), or uncensored (true) healing times. The effect that the treatments had on healing times were investigated by use of notched box and whisker plots, life tables, and Cox regression models. The analysis indicated that treatment of calves with either antimicrobial reduced the healing time of corneal ulcers, compared with untreated controls. Calves treated with OTC had shorter periods with ulcers present on both eyes than did NFZ-treated calves. The healing time of the first ulcer on a calf was faster when treated with either antimicrobial than when not treated, but no significant difference between periods for OTC and NFZ treatments was found. Censored healing times were consistently longer than uncensored healing times. Box and whisker plots indicated that both treatments shortened healing times more than those for controls, and OTC shortened healing times more than did NFZ for responses A and B (but not C). Life tables showed that OTC healing times were shorter than those for controls, and NFZ shorter than controls for response B and C (but not A). Cox regression model (for response A) showed a borderline significant difference between times for OTC group and controls, and no significant difference between times for NFZ group and controls.
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