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Evaluation of the effects of stress in cats with idiopathic cystitis
2006
Westropp, J.L. | Kass, P.H. | Buffington, C.A.T.
Objective-To determine the effects of stress in cats with feline idiopathic cystitis (FIC) by evaluating bladder permeability, sympathetic nervous system function, and urine cortisol:creatinine (C:Cr) ratios during periods of stress and after environmental enrichment. Design-Prospective study. Animals-13 cats with FIC and 12 healthy cats. Procedure-Cats subjected to an acute-onset moderate stressor for 8 days received IV injections of fluorescein. Serum fluorescein concentrations were determined and compared with those of controls to evaluate bladder permeability, and urine C:Cr ratios were compared to evaluate function of the hypothalamic-pituitary-adrenal (HPA) axis. Plasma catecholamine concentrations were analyzed in a subset of cats. After 8 days of moderate stress, cats were moved to an enriched environment, and tests were repeated after 21 days. Results-Serum fluorescein concentrations were significantly higher in cats with FIC at all time points. In the cats in which plasma catecholamine concentrations were determined, concentrations of dihydroxyphenylalanine, norepinephrine, and dihyroxyphenylglycol were significantly higher in cats with FIC at all time points, whereas no differences in urine C:Cr ratio between groups were observed. Conclusion and Clinical Relevance-Cats with FIC appeared to have altered bladder permeability, most notably during the period of initial stress. The increase in plasma dihydroxyphenylalanine concentration suggests that there may be stress-induced increase in the activity of tyrosine hydroxylase, which catalyzes the rate-limiting step in catecholamine synthesis. In contrast, no effects of stress on C:Cr ratios were observed, which suggests there was dissociation between the sympathetic nervous system and HPA-axis responses to stress.
显示更多 [+] 显示较少 [-]Biomechanical properties of canine corticocancellous bone frozen in normal saline solution
1995
Griffon, D.J. | Wallace, L.J. | Bechtold, J.E.
Eleven pairs of canine metacarpal bones, 10 pairs of metatarsal bones, and 7 pairs of ribs were harvested cleanly and prepared for banking at -20 C for 1 year. One bone of each pair was randomly assigned to 1 type of storage: plastic pack vs immersion in a normal solution of sodium chloride. The contralateral bone was assigned to the opposite treatment. Six pairs of metacarpal bones and 5 pairs of metatarsal bones were tested in torsion to failure. No significant difference was found within pairs. All ribs, 5 pairs of metacarpal bones, and 5 pairs of metatarsal bones were loaded in 4-point bending to failure. The energy absorbed at failure and the ultimate displacement of ribs and metacarpal and metatarsal bones were increased by 25 to 30% and 18 to 24%, respectively, when the bones were frozen in isotonic saline solution. Corticocancellous grafts frozen in normal saline solution are biomechanically less fragile and brittle than grafts stored in plastic without saline solution.
显示更多 [+] 显示较少 [-]Effects of temperature and storage time on pin pull-out testing in harvested canine femurs
1995
Huss, B.T. | Anderson, M.A. | Wagner-Mann, C.C. | Payne, J.T.
Effects of temperature and storage time on canine bone-transfixation pin specimens were tested by comparing pin pull-out forces. A total of 16 femurs from 8 mature dogs were tested. Five nonthreaded Steinmann pins were placed through both cortices in the diaphysis of each femur. The femurs were then sectioned transversely between each pin, with a bonepin specimen placed evenly into each of 5 groups prior to biomechanical testing. Four bone-pin specimen groups were stored at -20 or -70 C for 14 or 28 days, while 1 specimen group was immediately tested. Pull-out forces for frozen groups were compared with pull-out forces for the fresh group. Using two-way ANOVA, there was no statistical difference in mean axial-extraction forces among bonepin specimen in any of the tested groups. It is concluded that acute pin pull-out forces are not significantly affected by freezing temperature or time. However, specimens stored at -20 C for as few as 14 days had a trend for increased pull-out forces, compared with freshly harvested specimens. Therefore, the authors recommend storage of bone-pin specimens at -70 C when possible.
显示更多 [+] 显示较少 [-]Effects of short-term restraint stress on plasma concentrations of catecholamines, beta-endorphin, and cortisol in gilts
1995
Roozen, A.W.M. | Tsuma, V.T. | Magnusson, U.
The effects of short-term restraint stress, by means of snaring, on plasma concentrations of catecholamines, beta-endorphin, and cortisol were studied in 6 gilts. A catheter was inserted into the jugular vein, and 2 blood samples were collected before onset of stress. Thereafter, a hog snare was applied, and blood samples were collected at 0.5, 2, and 3.5 minutes after the start of snaring. Plasma epinephrine and norepinephrine concentrations increased (P < 0.001) within 0.5 minute after start of restraint and decreased thereafter. Plasma concentration of beta-endorphin increased (P < 0.05) within 2 minutes after start of restraint, whereas that of cortisol increased (P < 0.05) 3.5 minutes after start of restraint. Taken together, short-term stress, such as snaring, may increase the plasma concentration of catecholamines, beta-endorphin, and cortisol in pigs.
显示更多 [+] 显示较少 [-]Evaluation of bending strength of five interdental fixation apparatuses applied to canine mandibles
1993
Kern, D.A. | Smith, M.M. | Grant, J.W. | Rockhill, A.D.
Strength in bending was determined for inter. dental fixation apparatuses applied to hemimandibles obtained from 24 canine cadavers. Hemimandibles were osteotomized perpendicular to the long axis between the third and fourth premolars, and segments were stabilized with 1 of 5 interdental fixation apparatuses: Erich arch bar (EAB, n = 6); Stout loop (SL, n = 6); acrylic A, n = 6); Stout loop and acrylic (SLA, n = 24); and Erich arch bar and acrylic (EABA, n = 6). Ultimate strengths (mean +/- SEM) of EAB, SL, A, SLA, and EABA were 395 +/- 48; 523 t 57; 1,106 +/- 102; 1,306 +/- 156; and 2,707 +/- 504 N.m, respectively. Stiffness (mean +/- SEM) of EAB, SL, A, SLA, and EABA were 2,944 t 357; 6,322 +/- 2,201; 16,010 +/- 5,017; 15,777 +/- 1,026; and 27,079 +/- 5,576 N.m/ radian, respectively. Yield strengths (mean +/- SEM) Of EAB, SL, A, SIA, and EABA were 66 +/- 6; 264 +/- 19; 911 +/- 126; 1,114 +/- 159; and 1,855 +/- 401 N.m, respectively. There were no significant differences in acrylic weight, cross-sectional area of the acrylic, or area moment of inertia of acrylic at the osteotomy site among A, SIA, and EABA; and there were no significant differences in osteotomy surface area and area moment of inertia at the osteotomy site among all apparatuses (P > 0.05). The EABA apparatus had significantly higher mean ultimate strength, mean stiffness, and mean yield strength compared to other interdental fixation apparatuses. There were no significant differences in the mean ultimate strength, mean stiffness, or mean yield strength between EAB and SL (P > 0.05). Apparatuses that combine acrylic with metal reinforcement (SLA, EABA) were significantly stronger and stiffer than those that used metal alone (EAB, SL) or acrylic alone (A).
显示更多 [+] 显示较少 [-]Splenectomy in cattle via transthoracic approach
1992
Thompson, J.R. | Kersting, K.W. | Wass, W.M. | Davis, I.A. | Plumlee, K.H.
Sixty-eight cattle under general anesthesia were splenectomized. The transthoracic approach was used to provide better access to the spleen and to facilitate ligature of the major splenic vessels. The procedure was easier and less time-consuming, compared with other surgical approaches, and is considered to be less stressful to the animals. Postoperative recovery was complete in 67 of 68 cattle. After surgery, 1 animal developed respiratory tract disease that was thought to have been unrelated to the surgery.
显示更多 [+] 显示较少 [-]Effects of marketing stress on fecal excretion of Salmonella spp in feeder calves
1990
Corrier, D.E. | Purdy, C.W. | DeLoach, J.R.
Fecal samples were collected from 200 feeder-calves on farms in Tennessee, after assembly at a Tennessee auction market, and after transport to a Texas feedyard. A final fecal sample was collected from each calf after 30 days of feedyard confinement. The fecal samples were cultured for the presence of Salmonella spp. Salmonella isolates were serotyped and antimicrobial drug-resistance patterns determined. The number of calves fecal culture-positive for Salmonella spp increased from 0 on the Tennessee farms and auction market to 3/200 (1.5%) at entry into the Texas feedyard, and 16/200 (8%) after 30 days of feedyard confinement. Salmonella serotypes isolated and the number of isolates of each serotype were S reading (8), S cerro (4), S newbrunswick (3), S anatum (2), and S typhimurium (copenhagen; 2). All Salmonella isolates were resistant to 5 or more of 13 antimicrobial drugs tested. Salmonella reading isolates were resistant to 10 or 11 of 13 antimicrobial drugs. The results indicated that the calves could have been infected with Salmonella spp prior to or during the course of the study, and that marketing stress as they moved from farm through feedyard may have induced fecal excretion of salmonellae. In addition, the pattern of antimicrobial drug resistance in the Salmonella isolates was broad.
显示更多 [+] 显示较少 [-]Oxidative Stress in C100 Cells Induced by Combined Treatment of Benzo(a)pyrene and/or 2,3,7,8-Tetrachlorodibenzo-p-dioxin(TCDD)
Bae, M.O.;Choi, K.H.;Lee, H.J.;Kim, H.W.;Kim, J.S.;Hwang, S.K.;Park, J.H.;Cho, H.S.;Cho, M.H.(Seoul National University, Seoul, Republic of Korea)E-mail:mchotox@snu.ac.kr
When an organism is exposed to various toxicants chronically, reactive oxygen species(ROS) are accumulated and eventually result in several biological effects from gene expression to cell death. In the present study we investigated the oxidative damage of 2, 3, 7, 8-tetrachlorodibenzo-p-dioxin(TCDD) and/or benzo(a)pyrene (B(a)P) in C100 cells. C100 cells treated with TCDD(30 nM) and B(a)P(3 μM) underwent diverse oxidative stress as determined through thiobarbituric acid-reactive substances(TBARS) formation, DNA fragmentation, DNA single strand break(SSB) assay, immunohistochemical staining of 8-hydroxy-2'-deoxyguanosine(8-OHdG), and mRNA expressions of antioxidant enzymatic genes such as Cu/Zn-SOD gene, GPx(glutathione peroxidase 5) gene, and catalase gene.
显示更多 [+] 显示较少 [-]The relationship between high glucose-induced secretion of IGFs and PKC or oxidative stress in mesangial cells
Park, S.H.;Heo, J.S.;Han, H.J.(Chonnam National University, Gwangju, Republic of Korea)E-mail:hjhan@chonnam.ac.kr | Kang, C.W.(Chonbuk National University, Jeonju, Republic of Korea)
The proliferation of mesangial cells has been associated with the development of diabetic nephropathy. The cell proliferation has been regulated by diverse growth factors. Among them, insulin like growth factors(IGFs) are also involved in the pathogenesis of diabetic nephropathy. However, it is not yet known about the effect of high glucose on IGF-I and IGF-Ⅱ secretion and the relationship between high glucose-induced secretion of IGFs and PKC or oxidative stress in the mesangial cells.
显示更多 [+] 显示较少 [-]Influence of Moringa Oleifera leaf extract and synbiotic supplementation on mitigating stress of broilers subjected to high stocking density.
2024
Rasha Ragab | Abdelrahim H.A. Hassan | Hosney H. Emeash | Fatma Khalil
Environmental factors such as stocking density can cause stress and negatively affect the physiological status and meat quality of broiler chickens. In the current study, we evaluated the effects of increased rearing density on the growth performance, stress, fear levels, meat quality and liver histopathology of broilers as well as suggesting a use of different supplementations that may be helpful to reverse such adverse effects. Three hundred sixty one day-old cobb broilers (44.0 ± 5.24 g live-weights) were randomly distributed to 24 replicate pens to create two different stocking densities (D10 and D15 bird/m2) with the different supplementation treatments: 1) 10 birds/m2/pen (without any treatment, control, "CD10"), 2) 10 birds/m2/pen (moringa aqueous extract treatment "MAED10"), 3) 10 birds/m2/pen (synbiotic "SynD10"), 4)15 birds/m2/pen (without any treatment control SD15 "CD15"), 5) 15 birds/m2/pen (moringa aqueous extract treatment "MAED15"), 6) 15 birds/m2/pen (synbiotic "SynD15"). Results of the current study revealed that there was a significant increase in the overall experimental period body weight gain (P<0.01) with increasing density without affecting feed intake, body weight and feed conversion ratio. High stocking density resulted in significantly increased corticosterone (P>0.001), altered brain monoamines, deteriorated some carcass quality parameters and declined liver health. Additionally, it was concluded that moringa aqueous extract (MAE) and synbiotic (Syn) supplementation have a significant effect in reversing the catastrophic effect of high stocking density (SD) with minimal effect at the lower density groups.
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