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Cor pulmonale was diagnosed in a 4-year-old beef cow at pasture. Clinical and pathological evidence for the diagnosis included ventral oedema, respiratory distress, chronic interstitial pneumonia and cardiac failure. The cause of the pneumonia was not identified. 相似文献
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At 11 to 13 d after insemination, 1028 dairy cows on 19 farms were given an intramuscular injection of 10 micrograms of the GnRH analogue buserelin. Their reproductive performance was compared to 1022 control cows receiving a placebo. The GnRH analogue-treated cows had fewer short interoestrous intervals compared to the control cows, but there were no significant differences in pregnancy rates to either the insemination preceding or following treatment, in calving to conception interval, or to percent pregnant by the end of mating. There were no differences between treatments in herds of high, average or low pregnancy rate, in 2-year-old cows or cows greater than 2-years-old and in cows calved 40 d or less, or greater than 40 d. The use of 10 micrograms of the GnRH analogue, buserelin, 11 to 13 d after insemination, cannot be recommended as a method of improving reproductive performance in dairy herds. 相似文献
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Fish assemblage dynamics in an intermittent river of the northern Australian wet–dry tropics 
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下载免费PDF全文 Bradley J. Pusey Mark J. Kennard Michael Douglas Quentin Allsop 《Ecology of Freshwater Fish》2018,27(1):78-88
Intermittent rivers make up a large portion of the global river network and are the dominant river type in northern Australia. Increased pressure is being placed on such systems, and a better understanding of their ecology is needed. We examined, over a 7‐year period, the fish fauna of the intermittent Fergusson River, a major tributary of the Daly River of the northern Australia. Changes in habitat structure with the onset of the dry season involved contraction of the riffle/run/pool habitat to a single refugial pool, the size of which was determined by antecedent wet season hydrology. The fishes present comprised a subset of species present within the Daly River main channel and consisted of the most widely distributed of northern Australia's freshwater fishes. The Fergusson River provides suitable spawning habitat for species during the wet season (e.g. Hephaestus fuliginosus, Leiopotherapon unicolor and Neosilurus catfishes) and during the dry season for a different set of species (e.g. Amniataba percoides, Melanotaenia australis and Glossogobius aureus). Little year‐to‐year variation in assemblage structure was observed early in the dry season, whereas interannual variation in late dry season assemblages was substantial. Dry season recruitment imparted some of the interannual variability in assemblage structure recorded between late dry season samples. Piscivorous fishes were an important, but temporally variable, component of the assemblage present in the late dry season refugial habitat, and predation was potentially another important source of variation in assemblage structure. 相似文献
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