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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   
3.
Bees have rules     
Honey bees frequently dance with some view of the sky, orienting themselves to the sun or natural patterns of polarized skylight. Three new conventions have been discovered in the dance language which are used in these circumstances to eliminate potential ambiguity in the dance message.  相似文献   
4.
Darwin novelized     
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5.
Gould JD  Boies SJ 《Science (New York, N.Y.)》1978,201(4361):1145-1147
It is commonly assumed that dictation requires a long time to learn, but authors eventually dictate much faster than they write. Performance results now show that novice dictators can learn in a few hours to dictate with the speed and quality with which they write. However, they do not think they perform this well. Dictators with years of experience are from 0 to 25 percent faster than novices, depending upon the complexity of the letters. Planning time is about two-thirds of composition time, regardless of the method of composition.  相似文献   
6.
Rotaviruses (RV) have a high prevalence in piggeries worldwide and are one of the major pathogens causing severe diarrhoea in young pigs. RV species A, B, and C have been linked to piglet diarrhoea in Australian pig herds, but their genetic diversity has not been studied in detail. Based on sequencing of the structural viral protein 7 (VP7) RVA G genotypes G3, G4 and G5, and RVC types G1, G3, G5, and G6 have been identified in Australian piggeries in previous studies. Although occurrence of RVB was reported in Australia in 1988, no further genetic analysis has been conducted. To improve health management decisions in Australian pig herds, more information on RV prevalence and genetic diversity is needed. Here, 243 enteric samples collected from 20 pig farms within Eastern Australia were analysed for the presence of RV in different age groups using a novel PCR-based multiplex assay (Pork MultiPath™ enteric panel). RVA, RVB, and RVC were detected in 10, 14, and 14 farms, respectively. Further sequencing of VP7 in selected RV-positive samples revealed G genotypes G2, G5, G9 (RVA), G6, G8, G14, G16, G20 (RVB), and G1, G3, G5, G6 (RVC) present. RVA was only detected in young (<10 weeks old) pigs whereas RVB and RVC were also detected in older animals (>11 weeks old). Interestingly, RVB and RVC G-type occurrence differed between age groups. In conclusion, this study provides new insights on the prevalence and diversity of different RV species in pig herds of Eastern Australia whilst demonstrating the ability of the Pork MultiPath™ technology to accurately differentiate between these RV species.  相似文献   
7.
Bovine respiratory disease (BRD) exerts a major impact on the beef cattle industry nationally and worldwide, with a range of aetiological factors impacting its pathogenesis. Previous research has focussed on an increasing number of bacteria and viruses that have been shown to play a role in eliciting disease. Recently, additional agents have been emerging as potential contributors to BRD, including the opportunistic pathogen Ureaplasma diversum. To determine if U. diversum was present in Australian feedlot cattle and if that presence was linked to BRD, nasal swabs were collected from a cohort of 34 hospital pen animals and compared to 216 apparently healthy animals sampled contemporaneously at feedlot induction and again after 14 days on feed at an Australian feedlot. All samples were subjected to a de novo polymerase chain reaction (PCR) assay targeting U. diversum in combination with other BRD agents. U. diversum was detected at a low prevalence in cattle at induction (Day 0: 6.9%, Day 14: 9.7%), but in a significantly greater proportion of cattle sampled from the hospital pen (58.8%). When considering the presence of other BRD-associated agents, co-detection of U. diversum and Mycoplasma bovis was most common in hospital pen animals receiving treatment for BRD. These findings suggest that U. diversum may be an opportunistic pathogen involved in the aetiology of BRD in Australian feedlot cattle, in combination with other agents, with further studies are warranted to identify if a causal relationship exists.  相似文献   
8.
9.
OBJECTIVE: To determine historical, physical examination, clinicopathologic, and postmortem findings in horses with putative uremic encephalopathy. Design-Retrospective study. Animals-5 horses with renal failure and neurologic disease not attributable to abnormalities in any other organ system. PROCEDURE: Medical records from 1978 to 1998 were examined for horses with renal disease and neurologic signs not attributable to primary neurologic, hepatic, or other diseases. Signalment, history, physical examination findings, clinicopathologic data, renal ultrasonographic findings, and postmortem data were reviewed. RESULTS: Of 332 horses with renal disease, 5 met selection criteria. Historical findings, physical examination findings, clinicopathologic data, ultrasonographic data, and postmortem findings were consistent with chronic renal failure. Swollen astrocytes were detected in all 4 horses examined at necropsy. CONCLUSIONS AND CLINICAL RELEVANCE: A single criterion was not determined to be pathognomonic for uremic encephalopathy in horses. Uremic encephalopathy should be considered as a differential diagnosis in horses with evidence of chronic renal failure and encephalopathic neurologic sign not attributable to other causes. Astrocyte swelling, which was common to all 4 horses examined at necropsy, may serve as a microscopic indicator of uremic encephalopathy in horses.  相似文献   
10.
Twenty-nine dogs were diagnosed with hyperadrenocorticism (HAC). A single determination of endogenous plasma adrenocorticotropic hormone (ACTH) and adrenal ultrasonography were used in a prospective study to differentiate between pituitary-dependent HAC (PDH) and adrenal-dependent HAC (ADH). In 27 out of the 29 dogs (93 per cent), both endogenous plasma ACTH concentrations and adrenal ultrasonography indicated the same cause of HAC. Twenty-one of the 29 cases (72 per cent) were shown to be pituitary-dependent; all had plasma ACTH concentrations of greater than 28 pg/ml (reference range 13 to 46 pg/ml) and both adrenal glands were ultrasonographically of similar size and of normal shape. All 21 cases responded well to mitotane therapy. Six cases (21 per cent) were shown to be adrenal-dependent; all had plasma ACTH concentrations below the limit of the assay (<5 pg/ml) and the presence of an adrenal mass on ultrasonography. The sensitivity and specificity of adrenal ultrasonography and endogenous ACTH determinations to identify the cause of HAC were demonstrated to be 100 per cent and 95 per cent, respectively, for ADH. These discriminatory tests are more accurate than published figures for dexamethasone suppression testing.  相似文献   
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