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The effects of offspring sex, weight, age, and level of interaction with the dam on responses to weaning were examined to assist in the development of a weaning protocol for alpacas. In the first study, preand post-weaning activities, and weight change over Days -12-0,0-7 and 7-16 with respect to weaning, were recorded for 20 dam-offspring (hembra-cria) pairs aged 81-200 days. Pre-weaning changes in dam and offspring weights were positively related (P<0.05). Although heavier crias tended to be found closer to their dams than lighter crias (P<0.05) no additional effect of age on the dam-offspring relationship was found. Following weaning, cria growth rates were low over Days 0-7 but improved over Days 7-16, and hembra weight change followed the same pattern. Over Days 0-2, grazing and sitting activities of hembras and crias were replaced by standing and walking along paddock fencelines, although by Day 2 fenceline activities had decreased (P<0.05). Crias which were more frequently observed at fencelines had lower post-weaning growth rates (P<0.05). In the second study, pre-weaning sucking behaviour, and weight change over Days -30-0, 0-8 and 8-16 with respect to weaning, were recorded for 19 hembra-cria pairs aged 124-160 days. During 10 hours of observation on Days -5 and -4, the total duration of sucking by individual crias varied from 0-18 minutes, and the mean +/- SEM duration of sucking was 1.94 +/- 0.113 minutes. Cria sucking behaviour was positively related to growth rate prior to and weight at weaning (P<0.05). As in the first study, pre-weaning changes in dam and offspring weights were positively related (P<0.05). Following weaning, growth rates of the crias were depressed and the hembras lost weight over Days 0-8 and 8-16. The changes in growth rate and behaviour in Studies 1 and 2 indicated that weaning can be stressful for hembras and crias. However, there was no evidence from either study that pre-weaning behavioural or physical characteristics were related to the changes.  相似文献   
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Malignant catarrhal fever was diagnosed in a newly imported swamp buffalo calf. This disease is prevalent in deer and cattle in New Zealand and causes sporadic losses in these species. The disease is recognised as a problem in buffaloes overseas and this paper records the first case in a swamp buffalo in New Zealand.  相似文献   
997.
Replant disease is a common phenomenon in asparagus growing in the Netherlands. It is distinct from the decline phenomenon reported from many other asparagus producing area’s. The involvement of autotoxins from root residues of former asparagus crops was evaluated. Residues of aspar agus roots decompose extremely slowly. At two locations, each with fields where asparagus production was terminated 1 and 10 years before, biomass of root residues was 4180 and 11060 kg dw ha?1 after 1 year and 420 and 1140 kg dw ha?1 after 10 years.Although 10-year-old residues were for the greater part decomposed, crude aqueous extracts inhibited root growth of asparagus seedlings significantly and even more of garden cress. In root observation boxes with field soil mixed with non-sterilized or sterilized asparagus root fragments, growth of secondary roots was inhibited. Non-sterilized strawberry roots did not inhibit root growth, suggesting that effects of organic matter were not involved. In a pot experiment, sterilized asparagus root fragments inhibited root growth when added at a rate of 20 g1?1, but not a 2 g1?1 Addition of non-sterilized root fragments strongly inhibited root growth at both levels. This was probably due to simultaneous infection byFusarium oxysporum present in these residues. When an asparagus field is replanted, the amount of root residues left behind in soil after termination of the crop in the previous season is about 2 g dw 1?1, that corresponds to approx. 11000 kg dw ha?1. This level is too low for considering direct growth inhibition by autotoxins as a major factor. Their possible indirect effects are briefly discussed.  相似文献   
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Scuderi LA 《Science (New York, N.Y.)》1993,259(5100):1433-1436
Tree ring data have been used to reconstruct the mean late-season (June through January) temperature at a timberline site in the Sierra Nevada, California, for each of the past 2000 years. Long-term trends in the temperature reconstruction are indicative of a 125-year periodicity that may be linked to solar activity as reflected in radiocarbon and auroral records. The results indicate that both the warm intervals during the Medieval Warm Epoch ( approximately A.D. 800 to 1200) and the cold intervals during the Little Ice Age ( approximately A.D. 1200 to 1900) are closely associated with the 125-year period. Significant changes in the phase of the 125-year temperature variation occur at the onset and termination of the most recent radiocarbon triplet and may indicate chaotic solar behavior.  相似文献   
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