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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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一.緒言現行的役馬飼養標準,為數甚多。由於工作的計算困難,大都祇對於某種農業情况,加以大約的估計,因此用量的大小極不一致,而又無適當可行的辦法加以比較,以便抉擇。此中情況,林敦氏(1950)有言,"最好的方法是按照下述的辦法來飼養,如感覺馬的體情退化則增加飼量,如馬有長肥的傾向則減少之"。同樣波波夫亦謂,"必須不斷地注意馬的體况,並根據觀察結果,經常調整馬的日糧"(1954)。似此,則役馬的飼養仍處於一種技術修養的狀態,談不到定額矣。本文的目的在提出一衡量工作的尺度,根據此尺度,測驗各家的標準,並從而求出一比較合理的標準,此標準不但要按照飼養乳牛的辦法,計役授糧,而且要應用簡便,易於實行。此外,不同輕重及種類的工作,經測定各種的常數以後,亦可以納入本方法之中,俟一一論及之。  相似文献   
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The bromine content of potato tubers grown in soil fumigated with methyl bromide at 487 and 975 kg/ha (1 lb and 2 lb/100 ft2) averaged 170 and 280 mg/kg of dry weight. Most of the bromine was in the outer layers of the tubers; peeled tubers has less than 100 mg/kg, which remained after boiling. Potato haulm contained 4000 or 6700 mg/kg bromine respectively for the two rates of application. The bromine content of wheat grain grown after potatoes depended on the rate of application of methyl bromide and the time interval between treatment and wheat crop. Wheat grain harvested 31/2 21/2 and 11/2 years after fumigation with methyl bromide at 975 kg/ha had mean bromine contents of 4.5, 15 and 44 mg/kg. but the amounts in grain from plots having the same treatments varied more than two-fold; wheat grain harvested 11/2 years after fumigation at 487 kg/ha contained 23 mg bromine/kg. Wheat yields were unaffected by fumigation.  相似文献   
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Using a hand-held optical fiber, a surgical neodymium:yttrium, aluminum, and garnet laser was used transsclerally on the left ciliary body of 25 dogs. Dogs were assigned to groups and were given low (100 J) and high (238 J) energy levels. In 12 dogs given 100-J energy, the intraocular pressure decreased a mean value of 6 mm of Hg below that in the untreated right eye. However, intraocular pressure returned to the pretreatment value 1 week after treatment. Intraocular lesions were not found by histologic examination 28 days later. In the second group of 13 dogs treated with 238-J energy, 6 were euthanatized 7 days after treatment and 7 were euthanatized 28 days after treatment. A mean decrease in intraocular pressure of 10 mm of Hg in the treated left eye, relative to the untreated right eye, persisted throughout the evaluation period. In eyes examined histologically 7 days after treatment, ciliary hemorrhage and necrosis were prominent. Other histologic changes were minimal and consisted principally of iris stromal hemorrhage. Of 7 dogs examined for 28 days after treatment, 6 remained sighted; in 1 dog, extensive intraocular hemorrhage occurred, eventually resulting in phthisis bulbi. Ciliary atrophy and fibrosis were the important histologic lesions observed 28 days after treatment. Laser energy delivered transsclerally by this optical system effectively induced ciliary necrosis and may be an effective treatment for canine glaucoma.  相似文献   
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This prospective cohort study was designed to confirm the association between Congo red binding Escherichia coli (CREC) and E. coli air sacculitis in commercial broilers. It was also designed to evaluate CREC as an air sacculitis risk factor and to explore the CREC relationship to other air sacculitis risk factors (poultry house temperature, air-ammonia levels, and presence of other diseases). In addition, this study was used to assess a possible role of the broiler-breeder flocks and hatchers in the spread of CREC air sacculitis. Congo red E. coli-associated airsacculitis risk was based on CREC exposure of the chicks in the hatchers. Breeder flocks with greater than 30 CREC colonies/plate from hatcher air sampling tests were placed in the high risk group; flocks with less than five CREC colonies/plate were placed in the low risk group. Increased risks of death due to air sacculitis (RR = 2.26), and increased death rates due to CREC air sacculitis (RR = 9.45) in high-risk flocks, identified CREC as an important air sacculitis risk factor. The attributable risk percent of CREC airsacculitis from hatcher exposure of CREC was 89.4%, pointing to the hatcher as the source of CREC infection. The association of specific broiler-breeder flocks to high levels of CREC in the hatchers, and subsequent air sacculitis, suggests that the broiler-breeders are the ultimate source of CREC.  相似文献   
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Western blot analysis showed that sweat gland cells from freely sweating horses expressed the water channel aquaporin-5 (AQP-5). Immunohistochemistry revealed a strong AQP-5-like activity reaction at the apical membrane of the glandular secretory cells, which was absent from the surrounding myoepithelium and all other skin structures. In anhidrotic horses, AQP-5 was also found at the apical membrane of the luminal sweat gland cells, but the level of expression reduced with the length of time that the animal had displayed anhidrosis. The level of AQP-5 expression was substantially reduced in animals with long-term anhidrosis, hence implicating water channel impairment as a possible factor in the development of this disorder.  相似文献   
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