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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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A combination vaccine (Bovi-Shield FP4 + L5, Pfizer Animal Health) containing modified-live virus (MLV) components against bovine herpesvirus-1 (BHV-1), bovine viral diarrhea virus BVDV), parainfluenza virus-3 (PI3), bovine respiratory syncytial virus (BRSV), and inactivated cultures of Leptospira canicola, grippotyphosa, hardjo, icterohaemorrhagiae, and pomona was evaluated for safety in pregnant beef and dairy animals. Heifers vaccinated prebreeding with the minimum immunizing dose (lowest antigen level initiating immunizing effects) of the vaccine's MLV BHV-1 or BVDV components and during pregnancy (approximately 200 days of gestation) with vaccine containing 10x doses of the same BHV-1 and BVDV components delivered live, healthy calves that were determined to be serologically negative (titer less than 1:2) for neutralizing antibodies to BHV-1 and BVDV prior to nursing. Additionally, in three field safety studies, previously vaccinated cows and heifers that received a field dose (vaccine containing antigen levels required for commercial sale of the MLV combination vaccine during either the first, second, or third trimester of pregnancy had abortion rates similar to those of pregnant cows and heifers vaccinated during the same stage of pregnancy with sterile water diluent.  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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Seismological investigations show that the Point Mugu earthquake involved north-south crustal shortening deep within the complex fault zone that marks the southern front of the Transverse Ranges province. This earthquake sequence results from the same stress system responsible for the deformation in this province in the Pliocene through Holocene and draws attention to the significant earthquake hazard that the southern frontal fault system poses to the Los Angeles metropolitan area.  相似文献   
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A 2-year-old sow aborted her entire near-term litter of 11. Gross and histologic examination of a fetus suggested a tuberculous infection, and a yellow-pigmented Mycobacterium avium serotype 1 was subsequently isolated from the fetal tissue. Efforts to rebreed the sow were unsuccessful. She was anergic to skin tests with purified protein derivative of M. avium on two occasions but had M. avium specific in vitro lymphocyte immunostimulation. Gross granulomatous lesions were found in the liver, kidneys, and endometrium when the sow was necropsied 5 months after the abortion. Histologic examination showed diffuse and focal non-encapsulated granulomas in lymph nodes, tonsils, kidney, liver, spleen, lung, and uterine and vaginal walls. There were a few encapsulated calcified foci in the endometrium. The centers of some granulomas in the tonsils, liver, kidneys, and some lymph nodes were caseated. The yellow-pigmented M. avium was isolated from the reproductive organs and from 11 of 12 other tissues cultured.  相似文献   
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AIM: To determine if migratory birds arriving in New Zealand in the Southern Hemisphere spring of 2004 were infected with the highly pathogenic avian influenza (AI) virus, H5N1.

METHODS: Cloacal and faecal samples were collected from migratory red knots following their arrival in New Zealand in October 2004. Two species of resident sympatric birds, wrybill and mallard duck, were sampled prior to, and following, the arrival of migratory birds.

RESULTS: No AI viruses were isolated from migratory or resident shorebirds. Non-pathogenic AI viruses were isolated from six resident mallard ducks, comprising the endemic subtypes H4 (n=2), H7 (non-pathogenic), H10, and H11 (n=2).

CONCLUSIONS: Highly pathogenic AI H5N1 virus was not detected in migratory shorebirds or sympatric water birds in the Firth of Thames, New Zealand, in 2004-2005, despite the possible proximity of migratory birds to outbreaks of the disease in East Asia in 2004.  相似文献   
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