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1.
Abstract The potential utility of pelvic fin rays as ageing structures was evaluated for southern US muskellunge Esox masquinongy Mitchill populations by comparing age estimates among three readers and against cleithrum estimates, and by comparing observed length changes of tagged fish with changes predicted from growth equations based on pelvic fin ray age estimates. Mean coefficient of variation in age estimates among all readers and between the two readers with prior ageing experience was 17.8% and 5.6%, respectively. Exact and within 1-year agreement rates between pelvic fin rays and cleithra were 76% and 100%, respectively. Mean (± 2 SE) estimated absolute error between observed and predicted length changes for 13 tagged muskellunge was 30 ± 14 mm. This evaluation indicated that pelvic fin rays may prove to be a useful, non-lethal method for ageing muskellunge in southern US waters. Validation studies are still needed to ensure that growth rings form consistently throughout fish's life span. 相似文献
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The practice of horse rugging has important implications for horse welfare and performance, but in Australia, rugging practices have not been properly documented. The objective of this study was to obtain an understanding of Australian horse rugging practices. An online survey reviewed the management of 2659 Australian horses over 12 months. Of the reported horses a total of 84.8% were rugged, although most owners (69.5%) indicated that they were unsure whether horses needed to be rugged at all. Rugging was felt by 59.8% of owners to be a requirement for horses in competition. Riding and competition were significantly associated with the use of rugs. Nearly all respondents (89.0%) felt that ‘over-rugging’ was a concern. However, 4.8% of owners would use up to 4 rugs at any one time on their horse and 21.4% of horses were still rugged in temperatures above 20°C in Australia. Many Australian horse owners (42.8%) also believe that horses feel cold if they are not rugged. Anthropomorphism when it comes to rugging horses cannot be justified as the horse has a much wider thermoneutral zone (TNZ) than humans. Australian climate, owner opinions, equestrian discipline and whether a horse is used for riding influence Australian horse rugging practices. However, current practices are based on limited available research and are not necessarily to the benefit of the horse. The major limitation was that the survey likely attracted respondents who are interested in the topic creating a self-selection bias. 相似文献
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J. D. COLLINS T. D. GRIMES W. R. KELLY J. K. KEALY E. C. MURPHY 《The Journal of small animal practice》1968,9(10):513-518
Abstract— The clinico-pathological and radiological features of two cases of effusive canine pleuritis are presented. In both instances Actinomyces-like organisms were encountered but attempts to culture them (using aerobic and anaerobic methods) were unsuccessful. In one case Salmonella dublin was obtained in cultures at all stages of the investigations. The zoonotic implications of these and simiIar cases are discussed.
Résumé— GL'auteur expose les caractéristiques clinico-pathologiques et radiologiques de la pleurite exsudative, observée chez deux chiens. Dans l'un et l'autre cas ont été décelés des organismes semblables à l'actinomycès, mais les tentatives de culture (en milieu aerobie et anaerobie) ont échoué. Dans l'un des cas, Salmonella dublin a été obtenue à tous les stades de l'investigation. L'auteur examine les aspects zoonotiques des deux cas étudiés et de cas semblables.
Zusammenfassung— Die klinisch-pathologischen und die radiologischen Befunde von zwei Fällen von Pleuritis exsudativa des Hundes werden dargestellt. In beiden Fällen wurden astinomy-cesähnliche Organismen gefunden, aber die Kulturversuche (mit aeroben und anaeroben Methoden) verliefen erfolglos. In einem Fall wurde Salmonella dublin in Kulturen aller Stadien der Untersuchung erhalten. Die zoonotische Bedeutung dieser und ähnlicher Fälle wird besprochen. 相似文献
Résumé— GL'auteur expose les caractéristiques clinico-pathologiques et radiologiques de la pleurite exsudative, observée chez deux chiens. Dans l'un et l'autre cas ont été décelés des organismes semblables à l'actinomycès, mais les tentatives de culture (en milieu aerobie et anaerobie) ont échoué. Dans l'un des cas, Salmonella dublin a été obtenue à tous les stades de l'investigation. L'auteur examine les aspects zoonotiques des deux cas étudiés et de cas semblables.
Zusammenfassung— Die klinisch-pathologischen und die radiologischen Befunde von zwei Fällen von Pleuritis exsudativa des Hundes werden dargestellt. In beiden Fällen wurden astinomy-cesähnliche Organismen gefunden, aber die Kulturversuche (mit aeroben und anaeroben Methoden) verliefen erfolglos. In einem Fall wurde Salmonella dublin in Kulturen aller Stadien der Untersuchung erhalten. Die zoonotische Bedeutung dieser und ähnlicher Fälle wird besprochen. 相似文献
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Abstract. White crappies, Pomoxis annularis Rafinesque, were collected from two Texas reservoirs during pre-spawn, post-spawn, and autumn periods to evaluate seasonal relationships of relative weight ( Wr ) to body composition. Seasonal variations in Wr corresponded to cycles of lipid as a percentage of body weight. Lipid content and liver weight as percentages of total body weight of crappies from a population where individuals had high Wr values were consistently higher than corresponding values for crappies from a population where individuals had low Wr values. During autumn, lipid content, and liver and gonad tissue as percentages of body weight were positively correlated with Wr, and moisture and protein were inversely related to Wr. Percentage of mature eggs was positively correlated to Wr in pre-spawn crappies. 相似文献
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Monensin controlled-release intraruminal capsule for control of bloat in pastured dairy cows 总被引:1,自引:0,他引:1
LB LOWE GJ BALL VR CARRUTHERS† RC DOBOS‡ GA LYNCH PJ MOATE PR POOLE† SC VALENTINE 《Australian veterinary journal》1991,68(1):17-20
Monensin, a polyether ionophore antibiotic, is potentially an important agent for bloat relief in dairy cows grazing temperate legume-based pasture. A series of studies was undertaken to determine the effect of monensin, when delivered continuously in the rumen of lactating dairy cows by means of controlled-release capsules (monensin CRC). Such devices release approximately 300 mg/head/day for 100 d. A short-term pilot study made at Ruakura, New Zealand, tested monensin CRC in cows selected for high susceptibility to bloat and grazing lucerne (Medicago sativa) or red clover (Trifolium pratense). Treatment significantly reduced the incidence of bloat, while milk yield and protein yield were increased. There was no effect on fat yield. Following the pilot study, 6 large-scale field experiments involving a total of 368 lactating dairy cows, were made in Australia and New Zealand to confirm the effectiveness of monensin CRC for bloat control and to measure the effect of such treatment on milk production and composition. A severe bloat problem occurred in 2 experiments, mild bloat occurred in 2 others, while no visual signs of bloat were observed in the remaining 2 experiments. Bloat was significantly (P less than 0.05) reduced by monensin CRC treatment when data was pooled over the 4 experiments in which bloat occurred. Daily milk yield was increased in all experiments from a mean of 17.7 in untreated groups to 18.8 kg/head/day (P less than 0.05) in monensin CRC-treated cows. Protein percentage was not affected by treatment, while there was a decrease from 4.29 to 4.10% fat, although total fat yield was not affected.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
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The amounts of clay visible in four thin sections from paleosol horizons (clay contents 9–32%) were measured by point counting. These sections were used as references for visual estimates, without point counting, of the amounts of clay in 14 further sections. The measurements and estimates were recorded on pore-free and gravel-free bases so they could be related to gravimetric analyses. Amounts of clay measured and estimated by area in these thin sections were between 1.6 and 3.1 times those determined gravimetrically. The reasons for these differences are discussed. Firstly, clay in soil thin sections contains much pore space beyond the resolution of the optical microscope and has an apparent density dependent on the amount of submicroscopic pore space. An edge effect also causes over-estimation of clay in soil thin sections and under-estimation of visible pore space. Components (clay, mineral grains, pores) are usually sloped at their borders with each other within the standard 25–30 μm (three-dimensional) thin sections. Clay, for instance, may overcap a pore at its border, hiding some pore space. The need for true two-dimensional images of soil pore patterns in image analysis is indicated. A nomogram has been constructed, using apparent density, to allow estimation of clay in thin sections of soils with any clay content. Coarse/fine ratios can be determined more accurately and estimates of clay can also be recalculated to provide illuvial to total clay ratios that are more meaningful. It is recommended that the micromorphological identification criterion for the argillic horizon be reassessed and that 4% illuvial to total clay in a soil thin section be adopted as the diagnostic cut-off. 相似文献
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