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991.
Creatine monohydrate supplementation and the quality of fresh pork in normal and halothane carrier pigs 总被引:8,自引:0,他引:8
Maddock RJ Bidner BS Carr SN McKeith FK Berg EP Savell JW 《Journal of animal science》2002,80(4):997-1004
The objective of this research was to examine the impact of supplementation with creatine monohydrate (CMH) on the quality of various muscles from normal and heterozygous halothane carrier pigs. Twenty-nine crossbred pigs, 16 normal (NN) and 13 halothane carrier (Nn) genotypes, were supplemented with 0 or 25 g x pig(-1) x d(-1) of CMH for 5 d before slaughter. Supplemented pigs gained 2.26 kg more weight (P < 0.05) during 5 d of supplementation. There were trends (P < 0.10) toward higher objective marbling scores and lower cooking loss for supplemented pigs. The 45-min pH was 0.27 units higher (P < 0.05) for supplemented pigs in the semimembranosus; CMH supplementation did not influence (P > 0.05) drip loss or muscle composition. Supplementation with CMH also resulted in lower L* values in two ham muscles, semitendinosus (5.15 units) (P < 0.05) and semimembranosus (1.95 units) (P < 0.10) for Nn carcasses. Genotype had significant effects on most quality indicators, with Nn carcasses producing lower-quality lean as evidenced by less desirable subjective and objective color and higher drip losses. Genotype also affected the composition of several muscles, with the NN carcasses having more fat and less moisture. 相似文献
992.
Clinical and echocardiographic findings in 10 dogs with vegetative bacterial endocarditis 总被引:2,自引:0,他引:2
Ten cases of bacterial endocarditis in the dog were studied by retrospective analysis of case records. Diagnosis of bacterial endocarditis was based on either strict clinical criteria or post mortem examination. A wide spectrum of presenting signs was seen including pyrexia, lameness, epistaxis, haemoptysis and dyspnoea. Haematological and biochemical abnormalities were non-specific and were attributed to the effects of septicaemia, embolism or chronic inflammation. Haemostatic abnormalities and, or, severe dysrhythmias appeared to be associated with a significantly poorer prognosis. Blood cultures were positive in four cases of eight that were cultured. Lesions compatible with bacterial endocarditis were detected in all eight cases that underwent echocardiographic examination. Right-sided vegetations present in two dogs were not detected by echocardiography. Two-dimensional echocardiography is a useful technique for the detection of vegetative endocarditis in the dog and allows rapid therapeutic intervention while blood culture results are pending. 相似文献
993.
Cheatgrass (Bromus tectorum L.) is an exotic annual grass causing ecosystem degradation in western US rangelands. We investigated potential mechanisms by which crested wheatgrass (Agropyron cristatum L. Gaertn., Agropyron desertorum [Fisch. {Ex Link} Scult.]) suppresses the growth and invasibility of cheatgrass. Research focused on monthly mineral soil N availability and the proportional concentration of NH4+-N in a crested wheatgrass community by microsite (crested wheatgrass, unvegetated interspace, shrub subcanopy) and soil depth (0–15, 15–30 cm) over a 1-yr period. Mineral soil N in crested wheatgrass microsites ranged from 0.24 to 1.66 mmol · kg-1 and was not appreciably lower than the other microsites or other ecosystems we have measured in the Great Basin. The molar proportion of NH4+-N in the mineral N pool of crested wheatgrass averaged over 85% for the year and is significantly higher than the other microsites and far greater than other plant communities we have measured in the Great Basin. We conclude that crested wheatgrass does not suppress cheatgrass by controlling mineral N below a threshold level; rather, we hypothesize that it may limit nitrification and thereby reduce NO3--N availability to the nitrophile cheatgrass. 相似文献
994.
Peripheral blood samples were collected randomly from 195 horses in various parts of Hungary, and the presence of microfilariae was evaluated by the Knott technique. On the basis of morphological identification 18 of the horses (9.2 per cent) were infected with Setaria equina, and the infection was confirmed in 10 animals by pcr and sequencing. The level of microfilaraemia was between 1 and 1138 larvae in 2 ml of blood. There was no correlation between the time of sampling or the sex of the animals (stallions versus mares) and the prevalence of infection, but the prevalence decreased with age. There was a significant association between the prevalence of microfilaraemia and the presence of still waters; positive samples were collected either in the region of Lake Balaton, the largest lake in the country, or at places with nearby ponds. 相似文献
995.
Comparison of the results of abdominal ultrasonography and exploratory laparotomy in the dog and cat
Pastore GE Lamb CR Lipscomb V 《Journal of the American Animal Hospital Association》2007,43(5):264-269
Results of preoperative ultrasonography and exploratory laparotomy were reviewed retrospectively in a series of 100 small animals to assess the agreement between ultrasonographic and surgical findings and to identify abdominal lesions likely to be missed by ultrasonography. Good agreement occurred between ultrasound reports and surgical reports in 64% of the animals, which supported the use of ultrasonography in potential surgical candidates. A major discrepancy was observed between the ultrasound report and surgical findings in 25% of the animals. Of the various types of pathology encountered in the study, gastrointestinal ulceration or perforation was the most likely lesion to be missed by ultrasonography. 相似文献
996.
Raekallio MR Kuusela EK Lehtinen ME Tykkyläinen MK Huttunen P Westerholm FC 《American journal of veterinary research》2005,66(2):260-265
OBJECTIVE: To compare the effects of pretreatment with dexamethasone, physical stress (exercise), or both on sedation and plasma hormone and glucose concentrations in dogs treated with dexmedetomidine (DEX). ANIMALS: 6 healthy purpose-bred Beagles. PROCEDURE: Dogs received 4 treatments each in a randomized order prior to i.v. administration of DEX (5 fLg/kg). Pretreatments were as follows: (1) i.v. administration of saline (0.9% NaCI) solution and no exercise (control group); (2) IV administration of dexamethasone (0.05 mg/kg) and no exercise (DM group); (3) i.v. administration of saline solution and exercise (EX group; 15 minutes of trotting on a treadmill at a speed of 2 m/s); and (4) i.v. administration of dexamethasone and exercise (DM+EX group). RESULTS: Following DEX administration, all dogs had similar times to recumbency and sedation index values, irrespective of pretreatment with values, irrespective of pretreatment with dexam-d ethasone or exercise. Plasma catecholamine concentrations decreased after DEX administration. Compared with control group dogs, plasma cortisol concentrations were higher in EX-group dogs prior to DEX administration and lower in DM- and DM+EX-group dogs following DEX administration. Administration of DEX decreased plasma cortisol concentration in EX-group dogs only. Plasma glucose concentration was not influenced by exercise or dexamethasone administration was lower than baseline concentrations at 30 minutes after DEX administration and returned to baseline values by 90 minutes. Heart and respiratory rates and rectal temperature increased during exercise. After DEX administration, these values decreased below baseline values. The decrease in heart rate was of shorter duration in dogs that underwent pretreatment with dexamethasone, exercise, or both than in control group dogs. CONCLUSIONS AND CLINICAL RELEVANCE: Pretreatment with dexamethasone, moderate physical stress (exercise), or both did not influence sedation or cause adverse effects in healthy dogs treated with DEX. 相似文献
997.
Footrot, caused by the strictly anaerobic bacterium Dichelobacter nodosus, is the most common cause of lameness in sheep in Great Britain but problems exist in association with its diagnosis and control. The fastidious nature of D. nodosus means that complex media and several weeks are required for characterisation. An alternative method to simplify and enhance the detection of D. nodosus in clinical samples is therefore highly desirable. In terms of control, anecdotal evidence from the farming community suggests that the commercially available vaccine, based on Australian isolates of D. nodosus, is not widely employed in this country due to its perceived inefficacy. Seven hundred and six isolates, collected from outbreaks in England and Wales, were therefore used to investigate these issues. A 16S rRNA PCR was adapted to detect D. nodosus in clinical material within 1 day of sampling; a 15% increase in detection compared with culture and less than 1% false negatives were achieved. This represents a major advance in the rapid diagnosis of footrot and will be of great value to practitioners and diagnostic laboratories. Bacterial virulence was tested using protease thermostability and zymogram assays, whilst serogrouping was performed by slide agglutination. All isolates demonstrated virulence patterns previously recorded in Australia and all nine serogroups of D. nodosus (A-I) were represented. Serogroup H was predominant. There was, therefore, no evidence for the presence of novel strains of D. nodosus compared with Australia suggesting the need for further investigation into farmers' views on the use of the commercial vaccine in Great Britain. 相似文献
998.
Kaese HJ Valberg SJ Hayden DW Wilson JH Charlton P Ames TR Al-Ghamdi GM 《Journal of the American Veterinary Medical Association》2005,226(11):1893-8, 1845
Five horses were examined because of signs of muscle stiffness, colic, or both. All 5 had been exposed to Streptococcus equi within 3 weeks prior to examination or had high serum titers of antibodies against the M protein of S equi. Horses had signs of unrelenting colic-like pain and focal areas of muscle swelling. Four horses were euthanatized. The fifth responded to treatment with penicillin and dexamethasone; after 3 weeks of treatment with dexamethasone, prednisolone was administered for an additional 10 weeks. Common hematologic and serum biochemical abnormalities included neutrophilia with a left shift and toxic changes, hyperproteinemia, hypoalbuminemia, and high serum creatine kinase and aspartate transferase activities. Necropsy revealed extensive infarction of the skeletal musculature, skin, gastrointestinal tract, pancreas, and lungs. Histologic lesions included leukocytoclastic vasculitis in numerous tissues and acute coagulative necrosis resembling infarction. These horses appeared to have a severe form of purpura hemorrhagica resembling Henoch-Sch?nlein purpura in humans and characterized by infarction of skeletal muscles. Early recognition of focal muscle swelling, abdominal discomfort, neutrophilia, hypoalbuminemia, and high serum creatine kinase activity combined with antimicrobial and corticosteroid treatment may enhance the likelihood of a successful outcome. 相似文献
999.
Scott PR 《Veterinary journal (London, England : 1997)》2005,170(1):33-40
This review approaches sheep welfare during the periparturient period from a veterinary practitioner viewpoint. At the most fundamental husbandry level, the general hygiene standards adopted on many sheep farms in the United Kingdom (UK) during the lambing period are unacceptable and require urgent improvement. Concerns also arise from obstetrical conditions attended by farmers which cause pain that can be identified using clinical criteria such as altered demeanour and behaviour of the ewe, and the presence of inflammation of the reproductive tract. Reduced production is evidenced by poor milk production and hungry lambs, the necessity to rear such lambs artificially and, in neglected cases, death of the ewe and her lambs. The correction of dystocia, periparturient vaginal, uterine and rectal prolapses is greatly facilitated after epidural injection of lignocaine, or a combination of xylazine and lignocaine administered by a veterinary surgeon. However, the perceived high professional fees charged for these services, and for Caesarean operations, result in few sheep receiving veterinary care, with such neglect directly contributing to poor welfare standards and an increased ewe mortality rate during the periparturient period. Whilst ending any welfare concern, the destruction of ewes rather than requesting veterinary services purely for economic reasons is a disturbing trend in sheep production in the UK and raises concerns regarding positive interaction between veterinary practitioner and farmer. In this article, veterinary treatments which provide effective analgesia are described and costed for obstetrical conditions in sheep. Recommended treatment protocols are described for the common obstetrical problems in sheep. In addition to appropriate treatment of obstetrical problems and alleviation of pain, if veterinary involvement could reduce ewe periparturient mortality from estimated figures of 4-2% this would save an estimated 400,000 ewes annually in the UK. Sheep welfare could be considerably improved by practising veterinarians providing practical instruction to small groups of clients with funding provided by government agencies. 相似文献
1000.
During the conduct of an experiment designed to examine the nutritional management of dairy cows in late pregnancy, four cows out of 72 suffered from acute haemoglobinuria two to four weeks after calving. Thirty-six thin and 36 fat cows were individually fed one of three diets based on a total mixed ration with different energy or protein concentrations during the last 3 to 4 weeks before expected calving date. After calving, cows grazed pasture and were offered 6 kg dry matter of pelleted concentrates daily. The P concentrations of the feeds offered suggested that the cows' diets were marginally deficient in P relative to requirements. Plasma P concentrations were significantly (P < 0.05) lower in fat cows than in thin cows during the first 6 weeks of lactation (0.87 versus 1.12 mmol/L), but precalving diet had no effect (P > 0.05). Concentrations of plasma inorganic P of the four fat cows that developed acute haemoglobinuria were less than 0.3 mmol/L. However, plasma P concentrations in another 12 cows, none of which displayed overt symptoms, declined to similar levels. It appeared that inadequate dietary P may have predisposed cows to acute haemoglobinuria, but the precipitating cause was not readily obvious. 相似文献