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1.
SUMMARY Twenty-five Thoroughbred (TB) and 25 Standardbred (SB) stables were visited to determine their feeding practices. The ingredients of the main feed of the day for a mature gelding of average size in full training were weighed at each stable. Nutrient content of diets was calculated using published data for the individual ingredients. Results are expressed as mean±sd. The estimated body weight of TB horses was 493±34 kg and 437±32 kg for SB horses. There was considerable variation in diet composition and nutrient intake between stables. The TB trainers fed 11.0±2.4 kg and SB trainers 11.8±2.5 kg per day. The concentrate component of the diet weighed 7.8±1.6 and 7.7±2.3 kg for TB and SB stables, respectively, and the roughage component for TB horses 3.3±1.4 and SB horses 4.1±1.4 kg per day. The digestible energy intake of horses at TB stables was 129±29 MJ per day and at SB stables 132±31 MJ per day. Crude protein intake of TB horses was 1452±363 g and SB horses 1442±338 g per day. There were differences in some feeding practices at TB and SB stables. Standardbred trainers fed more roughage than TB trainers. Standardbred trainers fed chaffed lucerne (alfalfa) and cereal hays as the major roughage, whereas TB trainers fed more hay. The major hay type fed by TB trainers was lucerne, whereas many SB trainers preferred clover hay. Both trainers fed oats as the major grain, but TB trainers fed slightly more maize (corn) than SB trainers. The SB trainers fed barley as part of the concentrate component of the diet, whereas TB trainers usually fed boiled barley and linseed oil in winter only. Although many trainers used vitamin and mineral supplements, this appeared unnecessary in many Instances, especially with respect to Iron. Calcium and NaCI supplementation was necessary for some diets. We concluded that while there was a wide range in feed intake and diet composition for both TB and SB horses, average nutrient intakes were similar to National Research Council (1989) recommendations for horses performing intense work.  相似文献   
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本论文研究了饲料加工的两个关键参数(调质温度和时间)对育肥猪颗粒饲料淀粉糊化度和维生素沉积的影响。日粮配方为含30%干酒糟及其可溶物的玉米-豆粕型基础日粮。整个试验中配方保持不变。本试验采用2×3双因子设计,调质温度分别为77℃和88℃,调质时间分别15秒、30秒和60秒。此外,本试验还设置一个对照组,对照组饲料不采用调质制粒工艺,而是采用粉料饲喂。因此,本试验共有7个处理组。采集调质后制粒前(热干粉)、制粒后冷却前(热制粒)、以及制粒冷却后(冷制粒)的样品,并分析这三种样品的总淀粉率、淀粉糊化  相似文献   
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A modified version of the Conditt and Baumgardner gas chromatographic/mass spectroscopic (GC/MS) method for determination of daminozide in peanut butter and raw peanuts is described. Daminozide in the food product is hydrolyzed to unsymmetrical dimethylhydrazine (UDMH) by sodium hydroxide digestion. The generated UDMH is distilled from the food matrix and captured by reaction with salicylaldehyde in a condensation trap. Resulting high pH distillates generated by peanuts and peanut products are adjusted back to a pH of 5-6 through addition of glacial acetic acid. After thermal incubation and extraction into methylene chloride, salicylaldehyde dimethylhydrazone is separated from interferences by capillary GC and quantitated by MS using the selective ion monitoring (SIM) mode. Quantitation of daminozide is based on the ratio of the salicylaldehyde dimethylhydrazone molecular ion (m/z 164) to the molecular ion (m/z 153) of the internal standard, 4-nitroanisole. Confirmation of daminozide identity is determined by relative intensity of the m/z 164 ion to the m/z 120 (C7H4ON) ion. Improved m/z 164 ion intensity and reduction of neighboring interferences due to acetic acid treatment permitted a daminozide detection limit of 0.005 ppm in a 50 g sample and an associated 0.02 ppm limit of quantitation. This modification is specific for high protein samples that generate high pH distillates such as peanuts and peanut products and is not specifically intended for analysis of low protein samples.  相似文献   
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Lymphocytes: circulation altered by trypsin   总被引:20,自引:0,他引:20  
Rat thoracic duct lymphocytes altered by trypsin in vitro do not circulate normally. At early intervals after transfusion of lymphocytes labeled with chromium-51 selective accumulation of radioactivity in the lymph nodes is abolished, while uptake in the spleen is not reduced. Later, the cells appear to "home" to lymph nodes and recirculate to the lymph.  相似文献   
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The effect of simple sugars on the agglutinating activity of phytohemagglutinin was studied. N-Acetyl-d-galactosamine selectively inhibits the agglutination of leukocytes and erythro- cytes by phytohemagglutinin.  相似文献   
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OBJECTIVE: To investigate the prevalence of anaemia (haemoglobin<11.0 to 13.0 g dl(-1) depending on age and sex group), iron deficiency (transferrin receptor concentration>8.3 microg ml(-1)) and vitamin A deficiency (serum retinol <0.7 micromol l(-1)) in adolescent refugees. DESIGN: Cross-sectional surveys. SETTING: Kakuma refugee camp in Kenya and seven refugee camps in Nepal. SUBJECTS: Adolescent refugee residents in these camps. RESULTS: Anaemia was present in 46% (95% confidence interval (CI): 42-51) of adolescents in Kenya and in 24% (95% CI: 20-28) of adolescents in Nepal. The sensitivity of palmar pallor in detecting anaemia was 21%. In addition, 43% (95% CI: 36-50) and 53% (95% CI: 46-61) of adolescents in Kenya and Nepal, respectively, had iron deficiency. In both surveys, anaemia occurred more commonly among adolescents with iron deficiency. Vitamin A deficiency was found in 15% (95% CI: 10-20) of adolescents in Kenya and 30% (95% CI: 24-37) of adolescents in Nepal. Night blindness was not more common in adolescents with vitamin A deficiency than in those without vitamin A deficiency. In Kenya, one of the seven adolescents with Bitot's spots had vitamin A deficiency. CONCLUSIONS: Anaemia, iron deficiency and vitamin A deficiency are common among adolescents in refugee populations. Such adolescents need to increase intakes of these nutrients; however, the lack of routine access makes programmes targeting adolescents difficult. Adolescent refugees should be considered for assessment along with other at-risk groups in displaced populations.  相似文献   
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