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991.
The objective of this experiment was to determine the effect of prerigor injection of several glycolytic inhibitors on pH, color, tenderness, and related traits of low-value beef cuts. The semimembranosus, triceps brachii, and supraspinatus muscles from each of 10 steer carcasses were removed 1 h postmortem. Control samples remained in the carcass at 2 degrees C for 24 h. Prerigor muscles were injected and tumbled with 10% (by weight) of one of four solutions: sodium citrate (NaC; 200 mM), sodium fluoride (NaF; 200 mM), sodium acetate (NaA; 200 mM), and calcium chloride (CaCl2; 300 mM). All muscles treated with NaC and NaF showed the highest pH and glycogen content (P < 0.05), indicating that glycolysis was inhibited. Injection of NaC in semimembranosus and supraspinatus produced the tenderest meat (P < 0.05), showing a greater increase in tenderization at 3 d than at 7 d postmortem. Treatment did not affect color or oxidation-reduction potential, but all treated muscles tended to be more oxidative (higher oxidation-reduction potential). Sodium citrate was identified as a potential compound to enhance tenderness of prerigor muscle without altering color. Further studies are required to investigate its effect on palatability traits and to provide a basis for commercial application of the process.  相似文献   
992.
REASONS FOR PERFORMING STUDY: Mucosal ulcers and, occasionally, small granulomas on the axial surface of one or both arytenoid cartilages have been found in TB yearlings presented for post sale endoscopic examination. OBJECTIVES: To determine the incidence, endoscopic characteristics and outcome of a group of Thoroughbred yearlings affected with mucosal ulcers and granulomas of the arytenoid cartilage. HYPOTHESIS: The incidence of mucosal ulceration of the arytenoid cartilages of yearling Thoroughbreds is relatively high compared to other upper airway abnormalities; and that the majority of mucosal ulcers heal uneventfully, although a small percentage may progress to a granuloma and, less commonly, to arytenoid chondropathy. METHODS: The findings of post sale, upper airway endoscopic examinations of 3312 Thoroughbred yearlings, during a 5 year period, were reviewed, including those abnormalities listed in the conditions of sale and others not listed but considered likely to cause airway obstruction. Information obtained from the medical record of horses that had mucosal ulceration or granuloma of the arytenoid cartilage included the location and size of the lesion(s), sex of the affected horse and the presence and nature of other concurrent abnormalities of the upper portion of the respiratory tract. Additional information included treatment and results of follow-up, endoscopic examination by the authors or attending veterinarian. RESULTS: Mucosal lesions were seen in 0.63% of yearlings evaluated, which represented the most common, documented condition of the upper portion of the respiratory tract. The mucosal ulcers of 15 of 19 horses were considered to have healed without complication during follow-up examination; one of the 19 horses was lost to follow-up. Two horses affected with bilateral, arytenoid mucosal ulceration developed a granuloma at each site of ulceration. One horse developed a granuloma at a site of ulceration and, subsequently, arytenoid chondropathy. CONCLUSIONS: Arytenoid mucosal ulceration in sales yearlings was a relatively commonly encountered abnormality and a small percentage progressed to granuloma or chondropathy. POTENTIAL RELEVANCE: The mucosa of the arytenoid cartilage, particularly at the rostral margin of the vocal process, should be examined carefully during endoscopic examination of the upper portion of the respiratory tract of Thoroughbred yearlings presented for sale. Because a small percentage of mucosal ulcers may progress to granuloma or, less commonly, chondropathy, identification of mucosal ulcers of the arytenoid cartilage seen during post sale, endoscopic examination warrants notification to the purchaser and sales company. Medical therapy of affected horses should be considered and follow-up endoscopic examination performed to determine if the lesion has healed.  相似文献   
993.
During a field trial to evaluate the efficacy of repeated vaccinations with bovine herpesvirus type 1 (BHV-1) marker vaccines, a glycoprotein E (gE)-negative BHV-1 strain was isolated from the nasal secretions of two cows, eight months after vaccination with a gE-negative live-attenuated vaccine, initially given intranasally, then intramuscularly. The strain isolated was characterised using immunofluorescence, restriction analysis and PCR. All the techniques used identified the isolated virus as a gE-negative BHV-1 phenotypically and genotypically identical to the Za strain used as a control.  相似文献   
994.
995.
REASONS FOR PERFORMING STUDY: Wound healing proceeds faster in ponies than in horses and complications during healing, such as wound infection, occur less frequently in ponies. Earlier studies suggested that this difference might be related to differences in the initial post traumatic inflammatory response. HYPOTHESIS: That polymorphonuclear leucocyte (PMN) function and profiles of humoral factors in local inflammatory processes are different in horses and ponies. METHODS: PMNs were isolated from venous blood of horses and ponies. Chemotaxis and reactive oxygen species (ROS) production was determined. Tissue cages were implanted in limbs and necks of horses and ponies and injected with carrageenan and, 3 weeks later, with LPS. In sequential samples of inflammatory exudate, the numbers of macrophages and PMNs and the production of PGE2, TNFalpha, IL-1, IL-6 and chemoattractants were determined. RESULTS: In vitro ROS production of PMNs was significantly higher in ponies than in horses, whereas in vitro PMN chemotaxis was significantly lower in ponies. In the tissue cages for both stimuli, the production of IL-1 and chemoattractants was significantly higher in ponies than in horses and remained so towards the end of the observation period in ponies. CONCLUSIONS: This study demonstrated a higher production of various inflammatory mediators by pony leucocytes. Despite the lower in vitro chemotaxis of pony PMNs, this higher in vivo production resulted in a stronger initial inflammatory response in ponies, as has been reported in studies on wound healing, through the attraction of leucocytes and triggering of the production of other cytokines. A stronger initial inflammation may promote healing by more rapid elemination of contaminants and earlier transition to repair. POTENTIAL RELEVANCE: Modulation of the initial inflammatory response might therefore be a valid option for therapeutic intervention in cases of problematic wound healing. Further, the intraspecies differences in leucocyte function may have an impact on many fields in equine medicine.  相似文献   
996.
Hepatic artery thrombosis is a major cause of graft failure in liver transplantation. Use of donor interponates are common, but results are controversial because of necrosis or thrombosis after rejection. Reperfusion injury, hypoxia and free radical production determinate the survival. The aim of the study was to create an 'ideal' arterial interponate. Autologous, tubular graft lined with mesothelial cells, prepared from the posterior rectus fascia sheath, was used for iliac artery replacement in eight mongrel dogs for six months under immunosuppression. Patency rate was followed by Doppler ultrasound. Eight grafts remained patent and another two are patent after one year. The patency rate was good (median Doppler flow: 370 cm/sec) and there was no necrosis, thrombosis or aneurysmatic formation. The grafts showed viable morphology with neoangiogenesis, appearance of elastin, smooth muscle and endothelial cells. Electron microscopy showed intact mitochondrial structures without signs of hypoxia. Tissue oxygenation was good in all cases with normal (< 30 ng/ml) myeloperoxidase production. In conclusion, this autologous graft presents good long-term patency rate. Viability, arterialisation and low thrombogenicity are prognostic factors indicating usability of the graft in the clinical practice without the risk of rejection. Further investigations such as cell cultures and standardisation are necessary.  相似文献   
997.
OBJECTIVE: To assess the use of flunixin meglumine as an adjunct treatment for diarrhea in calves. DESIGN: Clinical trial. ANIMALS: 115 calves with diarrhea that were 1 to 21 days old at enrollment. PROCEDURE: Calves that developed diarrhea were randomly assigned to receive no flunixin meglumine (controls), a single dose of flunixin meglumine (2.2 mg/kg [1.0 mg/lb]), or 2 doses of flunixin meglumine administered 24 hours apart. Serum IgG concentration and PCV were measured prior to enrollment in the trial. Calves were evaluated daily to determine rectal temperature, fecal consistency, demeanor, and skin elasticity score. The primary analytic outcome was days of sickness (morbid-days). RESULTS: Calves with fecal blood and treated with a single dose of flunixin meglumine had fewer morbid-days and antimicrobial treatments, compared with controls. Although not significant, calves given 2 doses of flunixin meglumine in 24 hours had fewer morbid-days than untreated control calves. Regardless of severity of diarrhea, calves without fecal blood did not benefit from the use of flunixin. For calves with fecal blood, failure of passive transfer (low serum IgG concentration) was an independent risk factor for increased morbid-days. CONCLUSIONS AND CLINICAL RELEVANCE: Treatment with a single dose of flunixin meglumine resulted in fewer antimicrobial treatments and morbid-days in calves with fecal blood. As observed in other studies, calves with failure of passive transfer were at high risk for poor outcomes. This emphasizes the importance of developing and implementing effective colostrum delivery programs on dairy farms.  相似文献   
998.
Several clinical variables were compared in two groups of 15 horses recovering from resection and anastomosis of a strangulated small intestine; 15 were treated with parenteral nutrition and 15 were starved routinely. There was some evidence that parenteral nutrition had a short-lived adverse effect on both the catheter sites and gastric emptying, but there were no marked adverse clinical effects and no evidence of any improvement in the horses' condition.  相似文献   
999.
1000.
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