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71.
Cromwell GL Cline TR Crenshaw JD Crenshaw TD Easter RA Ewan RC Hamilton CR Hill GM Lewis AJ Mahan DC Nelssen JL Pettigrew JE Veum TL Yen JT 《Journal of animal science》2000,78(10):2652-2658
A cooperative research study was conducted by members of a regional committee (North Central Regional Committee on Swine Nutrition [NCR-42]) to assess the variability in nutrient composition (DM, CP, Ca, P, Se, NDF, and amino acids) of 14 sources of wheat middlings from 13 states (mostly in the Midwest). A second objective was to assess the analytical variability in nutrient assays among 20 laboratories (labs; 14 experiment station labs and six commercial labs). Wheat middlings were obtained from each participating station's feed mill. The bulk density of the middlings ranged from 289 to 365 g/L. The number of labs that analyzed samples were as follows: DM and CP, 20; Ca, 16; P, 15; Se, 7; NDF, 10; and amino acids, 9. Each lab used its own analytical procedures. The middlings averaged 89.6% DM, 16.2% CP, .12% Ca, .97% P, 36.9% NDF, .53 mg/kg Se, .66% lysine, .19% tryptophan, .54% threonine, .25% methionine, .34% cystine, .50% isoleucine, and .73% valine. As expected, there was considerable variation in nutrient composition among the 14 sources (P < .01), especially for Ca (.08 to .30%) and Se (.05 to 1.07 mg/kg). "Heavy" middlings (high bulk density, >335 g/L), having a greater proportion of flour attached to the bran, were lower in CP, lysine, P, and NDF than "light" middlings (<310 g/L), having cleaner bran, resulting in negative correlations between bulk density and CP (r = -.61), lysine (r = -.59), P (r = -.54), and NDF (r = -.81). Each 1-percentage-point increase in CP in the wheat middlings was associated with .0235 (r2 = .61) and 2.1 (r2 = .39)-percentage-point increases in lysine and NDF, respectively. Lysine content was associated with NDF, CP, and bulk density of wheat middlings (r2 = .88). There was considerable variation among laboratories (P < .01) in analysis of all nutrients. The CV among sources (100 x sigmaS/mean) was greater than among labs (100 x sigmaL/mean) for CP, Ca, P, Se, and NDF, but the CV among labs was greater than that among sources for DM and all of the amino acids except lysine and phenylalanine. 相似文献
72.
Hill PB Auxilia ST Munro E Genovese L Silkstone MA Kirby B 《The Journal of small animal practice》2000,41(11):519-523
A nine-year-old, neutered female Shetland sheepdog was presented with crusted, ulcerative skin lesions affecting the footpads, commissures of the lips and the lateral canthi of the eyes. Histopathological examination of skin biopsies revealed changes consistent with superficial necrolytic dermatitis and biochemical analysis demonstrated elevated liver enzymes. Abdominal radiography revealed a small liver which, on ultrasonography, appeared diffusely mottled and showed changes suggestive of periportal fibrosis. On exploratory laparotomy, the pancreas appeared normal, but the liver was small and had multiple nodules throughout the parenchyma. This appearance was confirmed as cirrhosis on histopathological examination. The dog was placed on a hepatic support diet and treated with colchicine, essential fatty acid supplementation and raw egg yolks. After four weeks, the skin lesions had resolved and the dog remained free of clinical signs over a 22-month follow-up period. 相似文献
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Leigh Ann Clayton Tracey K Ritzman 《Veterinary Clinics of North America: Exotic Animal Practice》2006,9(3):511-518
A 6-year-old cockatiel was diagnosed with egg binding based on clinical signs, physical examination findings, radiographs, and lack of oviposition. Medical management failed to induce oviposition, and surgical salpingotomy was used to remove the egg from the oviduct. Sterile egg yolk peritonitis was diagnosed based on histology. Postoperative management with leuprolide acetate and husbandary changes successfully prevented egg production for at least 2.5 months after the event. 相似文献
76.
The potential negative environmental impact of manure and biological waste (BW) can be minimised at a profit by recycling plant nutrients in the food chain. Current large-scale livestock production, epizootic diseases and increasing globalisation increase the need for biosecurity, to minimise the risk of disease transmission to the food chain. Arable use of manure and BW can inadvertently spread infectious diseases; opinion differs concerning the risk levels. To obtain general acceptance for arable use, a hygienically safe end-product is needed. This paper provides a detailed discussion of treatment alternatives for co-treatment, i.e., mixture before treatment of manure and BW. Composting, anaerobic digestion and ammonia treatment are the three options given. A decision support tool is also presented and discussed. Suitable treatment methods must combine biosecurity aspects with environmental, economic and nutrient recycling aspects to create a beneficial whole-farm approach. 相似文献
77.
酶联免疫吸附测定法,灵敏度高,使用抗血清仅微量,是近年来用于诊断、鉴定植物病毒的先进方法之一。这一技术需要纯度高的抗血清,采用蛋白质A-琼脂糖CL-4B柱层析纯化后的抗烟草环斑病毒抗血清(抗TRSV-IgG),纯度高、灵敏,很适用于塑珠酶联免疫吸附测定法(Bead-ELISA)的抗体和酶标抗体的材料。 相似文献
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Effects of ractopamine on genetically obese and lean pigs 总被引:2,自引:0,他引:2
Twenty-eight genetically obese and 24 lean barrows (65.0 and 68.7 kg average BW, respectively) were allotted within genotype to a 16% CP corn-soybean meal basal diet or this basal diet + 20 ppm ractopamine (a phenethanolamine beta-adrenergic agonist) and allowed ad libitum access to feed for 48 d. Compared to lean pigs, obese pigs had lower ADG, gain to feed ratio, longissimus muscle area, predicted amount of muscle, and weights of trimmed loin and ham, ham lean, heart, spleen, kidney and gastrointestinal tract (P less than .05). Obese pigs also had shorter carcass but higher dressing percentage, backfat thickness, fat depth, fat area, untrimmed loin weight and fasting plasma urea N concentration (P less than .05). Dietary supplementation with 20 ppm ractopamine reduced daily feed intake and improved gain to feed ratio in both lean and obese pigs (P less than .05). Pigs fed ractopamine had shorter carcasses, less fat depth and fat area, smaller weights of stomach and colon plus rectum, but higher dressing percentages, longissimus muscle areas, weights of trimmed Boston butts, picnics and loins, ham lean and predicted amounts of muscle than pigs not fed ractopamine (P less than .05). Supplemental ractopamine had no effect on fasting plasma concentrations of urea N, nonesterified fatty acids, triglyceride or glucose (P greater than .05). No genotype x ractopamine interactions for the criteria described above were detected (P greater than .05). These results suggest that ractopamine will improve the efficiency of feed utilization and carcass leanness in swine with different propensities for body fat deposition. 相似文献
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