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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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Hobbs IF 《New Zealand veterinary journal》1985,33(7):112-116
Complement fixation and ELISA tests were carried out on 8772 bovine sera. Results showed that ELISA titres were, on average, approximately sixteen times higher than the corresponding C.F. titres. The specificity of ELISA appeared comparable to that of the C.F.T. There was no evidence to show that the ELISA could detect infection earlier than the C.F.T. 相似文献
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Key issues and research priorities in landscape ecology: An idiosyncratic synthesis 总被引:46,自引:41,他引:46
Landscape ecology has made tremendous progress in recent decades, but as a rapidly developing discipline it is faced with
new problems and challenges. To identify the key issues and research priorities in landscape ecology, a special session entitled
“Top 10 List for Landscape Ecology in the 21st Century” was organized at the 16th Annual Symposium of the US Regional Association
of International Association of Landscape Ecology, held at Arizona State University (Tempe, Arizona, USA) during April 25–29,
2001. A group of leading landscape ecologists were invited to present their views. This paper is intended to be a synthesis,
but not necessarily a consensus, of the special session. We have organized the diverse and wide-ranging perspectives into
six general key issues and 10 priority research topics. The key issues are: (1) interdisciplinarity or transdisciplinarity,
(2) integration between basic research and applications,(3) Conceptual and theoretical development, (4) education and training,
(5)international scholarly communication and collaborations, and (6) outreach and communication with the public and decision
makers. The top 10 research topics are: (1) ecological flows in landscape mosaics, (2) causes, processes, and consequences
of land use and land cover change, (3) nonlinear dynamics and landscape complexity, (4) scaling, (5) methodological development,
(6) relating landscape metrics to ecological processes, (7) integrating humans and their activities into landscape ecology,
(8) optimization of landscape pattern, (9)landscape sustainability, and (10) data acquisition and accuracy assessment. We
emphasize that, although this synthesis was based on the presentations at the“Top 10 List” session, it is not a document that
has been agreed upon by each and every participant. Rather, we believe that it is reflective of the broad-scale vision of
the collective as to where landscape ecology is now and where it may be going in future.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
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B Genz J Gerszon Y Pollock B Gleeson R Shankar MJ Sellars RJ Moser 《Australian veterinary journal》2023,101(4):153-163
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
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RJ Barnewall IB Marsh PMV Cusack F Galea N Sales JC Quinn 《Australian veterinary journal》2023,101(6):254-257
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
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H H Chang J W De Vries W E Hobbs 《Journal of the Association of Official Analytical Chemists》1979,62(6):1281-1284
The difference between the CB and Best Foods methods in extracting aflatoxins from peanut products has been studied. The CB method yields 60, 121, 35, and 22% higher results for aflatoxins B1, B2, G1, and G2, respectively for 4 samples of peanut meal and 6 samples of peanut butter studied. Both reverse phase liquid chromatography and thin layer chromatography were used to quantitate the extracted aflatoxins. 相似文献