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101.
Six 3‐year‐old goats (three males and three females) weighing 60.0 ± 18 kg (mean ± SD) were used to investigate the effect of medetomidine (MED; 20 µg kg?1 IV) and its antagonism with atipamezole (ATI; 100 µg kg?1 IV) on physiologic responses (heart rate (HR; beats minute?1), respiratory rate (RR; breaths minute?1), electrocardiogram (ECG), rectal temperature (T; °C), blood pressure (oscillometric; mm Hg), sedation (SED), posture (REC), analgesia (ALG), and stress‐related hormonal and metabolic responses (epinephrine and norepinephrine (high performance liquid chromatography with electrochemical detection), cortisol (COR; µg dL?1; radioimmunoassay), glucose (GLU; mg mL?1; enzymatic colorimetric assay), and free fatty acids (modified enzymatic colorimetric assay)); each goat received ATI or SAL in random order separated by 1 week. Jugular catheters were placed for drug administration and blood sampling (10–12 mL sample?1) using a lidocaine skin block (20 mg) 2 hours prior to beginning of each trial; during this trial, goats breathed room air. Physiologic parameters were measured, SED, REC, and ALG were scored, and blood samples were collected from jugular catheters at baseline (time = ?30 minutes), 5 minutes post‐MED administration (time = ?25 minutes), 25 minute post‐MED administration and immediately prior to antagonism (time = 0 minute), and at 5, 30, 60, and 120 minutes after administering ATI or SAL. ALG was tested by clamping the withers and metacarpus with hoof testers fitted with a force transducer to measure applied isometric force (lb) (a technique used previously in goats to evaluate analgesia). Continuous variables were analyzed by Repeated Measures analysis of variance (anova ); categorical data were analyzed using a Friedman Repeated Measures anova on ranks. A p‐value of <0.05 was considered significant. If a significant difference was found, a Dunnett's pair‐wise comparison of means was conducted. Differences between ATI and SAL were examined at 5, 30, 60, and 120 minutes using a paired t‐test with a Bonferroni correction. Administration of MED resulted in a decrease in T (38.7 ± 0.3 to 34.5 ± 0.4 °C), HR (78 ± 19 to 55 ± 9), and RR (31 ± 12 to 14 ± 5) over time; an increase in mean arterial blood pressure (90 ± 19 to 132 ± 23), COR (0.254 ± 0.125 to 4.327 ± 1.233), and GLU (82.0 ± 13.2 to 255.9 ± 38.9); and changes in SED (alert to marked sedation), REC (standing to recumbent), and ALG (metacarpus = 5 ± 2 to 14 ± 0; withers = 3 ± 2 to 14 ± 0). GLU was 62–70% higher at 60 and 120 minutes and COR was 336% higher after SAL than after ATI at 120 minutes; at 30, 60, and 120 minutes, T was 4–10% higher after ATI than SAL. There were no other significant differences. REC, SED, and ALG were antagonized after ATI. ATI did not antagonize the effect of MED on HR, RR, or MAP, but stabilized T and antagonized the increase in GLU and COR.  相似文献   
102.
103.
OBJECTIVE: To determine whether immunity against bovine respiratory syncytial virus (BRSV) mitigates the effects of 3-methylindole (3MI) on occurrence of bovine respiratory tract disease (BRD) and rate of gain in feedlot cattle. ANIMALS: 254 mixed-breed beef cattle. PROCEDURE: Cattle were randomly assigned to 1 of 3 groups at the time of arrival at the feedlot. One group was vaccinated with an inactivated BRSV vaccine, another was vaccinated with a modified-live BRSV vaccine, and the third was maintained as unvaccinated control cattle. On days 0 and 28, serum BRSV antibody concentrations were measured, using serum neutralizing and ELISA techniques. Serum 3MI concentrations were measured at feedlot arrival and 3 days later. Cattle were monitored for development of BRD. At slaughter, lungs were evaluated grossly for chronic lesions. RESULTS: Higher serum 3MI concentrations early in the feeding period were associated with lower mean daily gain. Control cattle were more likely to be treated for BRD after day 3, compared with cattle vaccinated with the modified-live BRSV vaccine. Humoral immunity against BRSV did not appear to modify the effect of 3MI on development of BRD or mean daily gain. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that abrogating the effects of 3MI and BRSV infection may improve the health and growth performance of feedlot cattle. However, in this study, immunity against BRSV did not appear to protect against the potential synergism between 3MI and BRSV infection, possibly because of the slow rates of gain of cattle included in the study or timing of sample collection.  相似文献   
104.
105.
A retrospective analysis of the clinical case histories of 10 domestic shorthaired cats that underwent omentalisation, using a vascular pedicle of greater omentum, of chronic non-healing axillary wounds was carried out. Wounds were debrided and closed in a primary fashion following omentalisation. The cats had undergone a modal number of three previous repair attempts over a three- to 18-month period (mean 11 months) before referral. Further dehiscence occurred in eight cases, requiring a modal number of one further attempt at closure of the wound. Other complications included incisional herniation (two cats), serous exudate from the axillary wound (two cats) and paracostal abscessation (one cat). Long-term cure was achieved in seven of the 10 cases, with wounds finally having healed at a mean of 24 days post-omentalisation. Chronic axillary wounds are particularly difficult to treat and there are no reports of consistently successful techniques for their repair. This report suggests that omentalisation of these wounds may be a step towards such a repair procedure.  相似文献   
106.
To improve the reproductive performance of water buffalo to level can satisfy our needs, the mechanisms controlling ovarian follicular growth and development should be thoroughly investigated. Therefore, in this study, the expressions of growth differentiation factor‐9 (GDF‐9) in buffalo ovaries were examined by immunohistochemistry, and the effects of GDF‐9 treatment on follicle progression were investigated using a buffalo ovary organ culture system. Frozen–thawed buffalo ovarian follicles within slices of ovarian cortical tissue were cultured for 14 days in the presence or absence of GDF‐9. After culture, ovarian slices were fixed, sectioned and stained. The follicles were morphologically analysed and counted. Expression pattern of GDF‐9 was detected in oocytes from primordial follicles onwards, besides, also presented in granulosa cells. Moreover, GDF‐9 was detected in mural granulosa cells and theca cells of pre‐antral follicles. In antral follicles, cumulus cells and theca cells displayed positive expression of GDF‐9. In corpora lutea, GDF‐9 was expressed in both granulosa and theca lutein cells. After in vitro culture, there was no difference in the number of primordial follicles between cultured plus GDF‐9 and cultured control that indicated the GDF‐9 treatment has no effect on the primordial to primary follicle transition. GDF‐9 treatment caused a significant decrease in the number of primary and secondary follicles compared with controls accompanied with a significant increase in pre‐antral and antral follicles. These results suggest that a larger number of primary and secondary follicles were stimulated to progress to later developmental stages when treated with GDF‐9. Vitrification/warming of buffalo ovarian tissue had a little remarkable effect, in contrast to culturing for 14 days, on the expression of GDF‐9. In conclusion, treatment with GDF‐9 was found to promote progression of primary follicle that could provide an alternative approach to stimulate early follicle development and to improve therapies for the most common infertility problem in buffaloes (ovarian inactivity).  相似文献   
107.
Over a 3-y period, 906,000 cattle were monitored in 23 feedlots in southern Alberta for symptoms of acute interstitial pneumonia (AIP). Plasma, urine, and lung tissue were collected at slaughter from 299 animals clinically diagnosed with AIP and from 156 healthy penmates and analyzed for 3-methylindole (3MI) derivatives and reduced glutathione concentration. From each animal, the left lung was subsampled for histologic examination. Concentrations of glutathione in lung tissue were reduced (P < 0.001) in animals showing clinical symptoms of AIP as compared with their asymptomatic penmates. Animals histologically confirmed as having AIP had higher levels of 3MI protein adducts in blood and lung tissue (P < 0.05) than did emergency-slaughtered animals without AIP. Within feedlots, where pens of heifers were fed either a standard dosage of melengestrol acetate (MGA) or none, the rate of death attributable to AIP was similar between treatment groups, but emergency slaughter after clinical diagnosis of AIP was done 3.2 times more often (P < 0.001) in the MGA-fed heifers than in the group not fed MGA. Use of MGA did not influence glutathione concentration. As growth performance of heifers given steroidal implants may not be improved by feeding MGA, the most cost-effective method of reducing the incidence of AIP-related emergency slaughter in feedlot heifers may be to eliminate MGA from the diet.  相似文献   
108.
109.
Although Salmonella remains one of the leading causes of foodborne illnesses in the United States, the Salmonella enterica serovars and genetic types associated with most infections appear to fluctuate over time. Recently, the Center for Disease Control and Prevention (CDC) has reported an increase in cases of salmonellosis caused by Salmonella 4,[5],12:i:-. Similarly, this unusual Salmonella serovar has been isolated from cattle and poultry in the state of Georgia. We examined the genetic relatedness of Salmonella 4,[5],12:i:-, isolated from several different poultry companies and dairy farms in Georgia, by pulsed-field gel electrophoresis (PFGE). Several Salmonella 4,[5],12:i:- isolates had PFGE patterns identical or similar to PFGE patterns of Salmonella Typhimurium isolated from numerous animal sources. We identified distinct PFGE patterns for Salmonella 4,[5],12:i:- and matching Salmonella Typhimurium PFGE patterns, identifying four "distinct" strains. We focused a more specific analysis on the poultry Salmonella 4,[5],12:i:- and Salmonella Typhimurium isolates and found that of these Salmonella 4,[5],12:i:- isolates, 32% lacked the entire phase 2 antigen gene, fljB; 61% contained partial deletion(s); and 4% had partial deletion(s) in fljB and an adjacent gene hin, 5' to fljB. Thirteen percent contained smaller deletions or point mutations not identified by our DNA probes. The Salmonella 4,[5],12:i:- isolates were positive for several genes present in the Salmonella Typhimurium, including lpfE (100%), sseI(96%), and spvC (93%). Genetic analysis indicates independent, spontaneous mutations in fljB in at least four distinct Salmonella Typhimurium strains of animal origin circulating in nature.  相似文献   
110.
Although agriculture generates 16% of Australia’s greenhouse gas emissions, it also has the potential to sequester large quantities of emissions through land use management options such as agroforestry. Whilst there is an extensive amount of agroforestry literature, little has been written on the economic consequences of adopting silvopastoral systems in northern Australia. This paper reports the financial viability of adopting complementary agroforestry systems in the low rainfall region of northern Australia. The analysis incorporates the dynamic tradeoffs between tree and pasture growth, likely forest product yields, carbon sequestration and livestock methane emissions in a bioeconomic model. The results suggest there are financial benefits for landholders who integrate complementary agroforestry activities into existing grazing operations at even modest carbon prices.  相似文献   
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