41 resultados para summer mortality

em Deakin Research Online - Australia


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The effects of animal species (AS; Angora goats, Merino sheep, mixed-grazed goats and sheep at the ratio of 1:1) and stocking rate (SR; 7.5, 10 and 12.5 animals/ha) on the liveweight, body condition score, carcass yield and mortality of goats and sheep were determined in a replicated experiment on improved annual temperate pastures in southern Australia from 1981 to 1984. The pattern of liveweight change was similar for both species with growth from pasture germination in autumn until maturation in late spring followed by weight loss. In winter, sheep grew faster than goats (65 versus 10 g/day, P < 0.05). In mixed-grazed treatments between November and December goats either grew when sheep were losing weight or goats lost less weight than sheep (P < 0.01). Both AS (P < 0.001) and SR (P < 0.001) affected liveweight of sheep and an AS SR interaction (P <  0.05) affected liveweight of goats. Mixed-grazed sheep were heavier than separately grazed sheep at all SR with a mean difference at 10 and 12.5/ha of 4.6 kg. Mixed-grazed goats at 10/ha were heavier than separately grazed goats from the end of the second year of the experiment, but at 12.5/ha, separately grazed goats maintained an advantage over mixed-grazed goats, with a 9.4-kg mean difference in December (P < 0.05). Body condition scores of goats and sheep declined with increasing SR; they were highest in late spring and were highly correlated with liveweight (r2 > 0.8). Both AS and SR affected (P < 0.001) carcass weight and GR tissue depth as a direct result of differences in liveweight. Adjusting for differences in carcass weight negated AS effects on GR tissue depth. The carcass weights of sheep and goats increased by similar amounts for each 1-kg increase in liveweight. Mortality of sheep (3.1% p.a.) was unaffected by AS or SR. An AS SR interaction indicated mortality of separately grazed goats at 12.5/ha and mixed-grazed goats at 10 and 12.5/ha were higher (P < 0.05) than all other goat (29 versus 9%) and sheep treatments, primarily because of increased susceptibility to cold stress. Disease prevalence differed between sheep and goats. Mixed grazing of Merino sheep and Angora goats produced complementary and competitive effects depending upon the SR. Goats used summer pasture better but winter pasture less well for liveweight gain than sheep. Angora goats should not be grazed alone or mixed grazed with sheep on annual temperate pastures at SR greater than that recommended for Merino sheep and the evidence indicates a lower SR will reduce risks associated with mortality.

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Caging and a mark–recapture design were used to estimate the growth rate of the brittle, infaunal bivalve Soletellina alba in the Hopkins River estuary. The growth of both caged and uncaged individuals was monitored at three sites near the mouth of the estuary over 180 days. Growth rates did not differ for caged and uncaged bivalves, or for bivalves subject to different amounts of handling, or between sites. Growth did differ between consecutive time intervals, which was attributable to negligible growth occurring during the colder months of autumn/winter. Comparisons of the condition (as indicated by total mass for length3) of S. alba were inconsistent between sites for caged and uncaged bivalves and for those subject to different amounts of handling. Soletellina alba is a rapidly growing bivalve with mean growth rates for the three time intervals being 0.04±0.002 mm day−1 in summer, 0.02±0.001 mm day−1 in autumn and 0.03±0.001 mm day−1 from summer to winter. Using existing literature, it was shown that a significant relationship exists between maximum shell length and onset of sexual maturity in bivalve molluscs. This relationship predicts that S. alba should reach the onset of sexual maturity at 15.8 mm length. Therefore, it appears that it may be possible for juvenile S. alba (<1 mm) to grow, reach sexual maturity and reproduce in between annual mass-mortality events caused by winter flooding.

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The Thai river sprat, Clupeichthys aesarnensis Wongratana, is a clupeid with a short life span, and supports artisanal fisheries in a number of reservoirs in the Mekong Basin. The growth parameters, mortality rates and the status of the Thai river sprat in Sirinthorn Reservoir (28 800 ha), NE Thailand (15°N; 105°E), are presented. The fishery is based on lured lift-nets, operated 7–14 days in the new moon period, September to April each year. It was shown that the von Bertalanffy growth function (VBGF) model was Lt (mm) = 78.43[1 − exp{−0.211[t − (−0.7996)]}] and its growth conformed to an isometric pattern. Natural mortality rate (month−1) was 0.13 month−1. Total mortality rates ranged from 0.69 to 1.53 month−1 depending on the weather and the fishing season. Recruitment was continuous throughout the year but peaked in June and July. The yield per recruit model indicated that the exploitation rate of this fishery is probably too high.

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Context: This paper reports on findings from the ex-post evaluation of the Maewo Capacity Building project in Maewo Island, Vanuatu, which was funded by World Vision Australia.
Objectives: To examine the extent to which the infrastructure and systems left behind by the project contributed to the improvement of household food security and health and nutritional outcomes in Maewo Island, using Ambae Island as a comparator.
Setting: Two-stage cluster survey conducted from 6 to 20 July 2004, which included anthropometric measures and 4.5-year retrospective mortality data collection.
Participants: A total of 406 households in Maewo comprising 1623 people and 411 households in Ambae comprising 1799 people.
Main outcome measures: Household food insecurity, crude mortality rate (CMR), under-five mortality rate (U5MR) and malnutrition prevalence among children.
Results: The prevalence of food insecurity without hunger was estimated at 15.3%
(95% confidence interval (CI): 12.1, 19.2%) in Maewo versus 38.2% (95% CI: 33.6, 43.0%) in Ambae, while food insecurity with hunger in children did not vary by location. After controlling for the child’s age and gender, children in Maewo had higher weight-for-age and height-for-age Z-scores than children of the same age in Ambae. The CMR was lower in Maewo (CMR ¼ 0.47/10 000 per day, 95% CI: 0.39, 0.55) than in Ambae (CMR ¼ 0.59/10 000 per day, 95% CI: 0.51, 0.67) but no difference existed in U5MR. The major causes of death were similar in both locations, with frequently reported causes being malaria, acute respiratory infection and
diarrhoeal disease.
Conclusions: Project initiatives in Maewo Island have reduced the risks of mortality and malnutrition. Using a cross-sectional ‘external control group’ design, this paper demonstrates that it is possible to draw conclusions about project effectiveness where baseline data are incomplete or absent. Shifting from donor-driven evaluations to impact evaluations has greater learning value for the organisation, and greater value when reporting back to the beneficiaries about project impact and transformational
development in their community. Public health nutritionists working in the field are well versed in the collection and interpretation of anthropometric data for evaluation of nutritional interventions such as emergency feeding programmes. These same skills can be used to conduct impact evaluations, even some time after project completion, and elucidate lessons to be learned and shared. These skills can also be applied more widely to projects which impact on the longer-term nutritional status of
communities and their food security.

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Background: At the height of the food crisis in southern Africa, the Government of Lesotho declared a state of famine and emergency in April 2002 and launched a Famine Relief Appeal for over $137 million. World Vision, in partnership with the World Food Program, became involved in December 2002 providing food aid to affected communities.
Objective: to document mortality rates, causes of death, malnutrition prevalence, and the proportion of lost pregnancies after almost three years of humanitarian response to the food crisis in Lesotho and to propose a way forward.
Design: A two-stage, 30 cluster household survey was undertaken in three districts from the 16th to the 26th of May 2005, with a sample size of 3610 people.
Results: The crude mortality rate (CMR) of 0.8/10,000/day (95%CI: 0.7-0.9). The reported CMR was significantly lower than the CMR emergency threshold (<1/10,000/day). Using 2000 as a pre-drought baseline, 38528 excess deaths occurred between 2000 and 2005. The under-five mortality rate (U5MR) of 3.2 deaths/10,000/day (95%CI: 2.8-3.6/10,000/day) was 4 times the reported CMR and 1.4 times higher the U5MR emergency threshold for sub-Saharan Africa (2.3/10,000/day). CMR was lower among food aid beneficiaries (0.68; 95%CI: 0.57-0.79) than non-beneficiaries (1.42; 95%CI: 1.13-1.70). This was also true for U5MR (2.94; 95%CI: 2.39-3.50 versus 6.44; 95%CI: 5.21-7.68). The prevalence of wasting increased from 5.4% to 12% while that of stunting declined from 45.4% to 36.2% between 2000 and 2005, but the nutritional status did not vary by beneficiary status.
Conclusion: Despite the alarming U5MR, findings suggest that the food aid program ensured survival mainly among adults. The situation could have been catastrophic in the absence of humanitarian assistance.

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An on-line site was created to support students studying a time shortened, off-campus unit in engineering management that was being offered over summer semester for the first time. An evaluation exercise was undertaken to assess the effectiveness of this arrangement, to identify what types of on-line resources students rated as important, and to identify those on-line resources that students actually used in their summer semester studies. Most students reported that they were successful in achieving their summer semester study goals, and that summer semester study was as good as or better than studying in a standard semester. The types of on-line resources ranked most highly by students were those that assisted in strategic study and exam preparation. The on-line resource ranked as least important and used least in practice was a discussion forum for all students. Other results and statistical analysis are presented.

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Developed in partnership between the Immigration Museum and Deakin University, this exhibition examines how eight different groups in Victoria deal with death. It includes representatives of Moslem, Hindu, Christian (Catholic, Anglican, Greek Orthodox), Jewish, Buddhist faiths and those with no religion.

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Many views of stream invertebrate populations centre on drift as the major route of larval dispersal, but few studies have presented unambiguous information about the role of drift. We present the results from an experiment designed to determine whether the major route of colonisation of substrata by hydropsychid larvae (commonly found in the drift) is by drifting directly onto substrata or by walking along the stream bottom. The experimental design contained four treatments: substrata open to drifters and walkers; fenced substrata open to drifters only; and two treatments open to drifters and walkers that provided forms of fence controls. Fifteen replicates of each treatment were set out at random locations within a riffle at each of three sites, with each site on a different river (the Little River, the Steavenson River and the Acheron River) in the Acheron River catchment. The experiment was run twice, once during autumn (April 1999) and once during early summer (January 2000). Both experiments were colonised by three species of hydropsychids, Asmicridea sp. AV1, and Smicrophylax sp. AV1 and AV2. We found that 2nd/3rd instars of Asmicridea sp. AV1 walked as well as drifted, whereas all others primarily drifted. No relation between numbers of recruits and water speed was found when substrata were open only to drifters, whereas substrata open also to walkers gained more recruits in faster flows. Additionally, larvae more frequently abandoned nets in slow than fast flows, indicating that drifting into unfavourable flow environments may result in mortality or redispersal of larvae. These findings demonstrate that, although drift is important, it is not necessarily the only method used by hydropsychids to colonise substrata. Larvae may have more capacity to choose substrata in fast flows when they colonise substrata by walking. Spot measures of hydropsychid distribution cannot distinguish between these explanations. The finding that walkers can sometimes comprise significant numbers of recruits raises the prospect that hydropsychids can be sourced locally and have not inevitably drifted in from upstream locations.

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Background: Tete Province, Mozambique has experienced chronic food insecurity and a dramatic fall in livestock numbers due to the cyclic problems characterized by the floods in 2000 and severe droughts in 2002 and 2003. The Province has been a beneficiary of emergency relief programs, which have assisted >22% of the population. However, these programs were not based on sound epidemiological data, and they have not established baseline data against which to assess the impact of the programs. Objective: The objective of this study was to document mortality rates, causes of death, the prevalence of malnutrition, and the prevalence of lost pregnancies after 2.5 years of humanitarian response to the crisis. Methods: A two-stage, 30-cluster household survey was conducted in the Cahora Bassa and Changara districts from 22 October to 08 November 2004. A total of 838 households were surveyed, with a population size of 4,688 people. Results: Anthropometric data were collected among children 6-59 months of age. In addition, crude mortality rates (CMRs), under five mortality rates (U5MRs), causes of deaths, and prevalence of lost pregnancies were determined among the sample population. The prevalence of malnutrition was 8.0% (95% confidence interval (CI)=6.2-9.8%) for acute malnutrition, 26.9% (95% CI=24.0-29.9%) for being underweight, and 37.0% (95% CI=33.8-40.2%) for chronic malnutrition. Boys were more likely to be underweight than were girls (odds ratio (OR)=1.34; 95% CI=1.00, 1.82; p<0.05) after controlling for age, household size, and food aid beneficiary status. Similarly, children 30-59 months of age were significantly less likely to suffer from acute malnutrition (OR=0.45; 95% CI=0.26, 0.79; p<0.01) and less likely to be underweight (OR=0.37; 95% CI=0.27, 0.51; p<0.01) than children 6-29 months of age, after adjusting for the other, aforementioned factors. The proportion of lost pregnancies was estimated at 7.7% (95% CI=4.5-11.0%). A total of 215 deaths were reported during the year preceding the survey. Thirty-nine (18.1%) children <5 years of age died. The CMR was 1.23/10 000/day (95% CI=1.08-1.38), and an U5MR was 1.03/10 000/day (95% CI=0.71-1.35). Diarrheal diseases, malaria, tuberculosis, and human immunodeficiency virus/acquired immunodeficiency syndrome (HIV/AIDS) accounted for more than two-thirds of all deaths. Conclusions: The observed CMR in Tete Province, Mozambique is three times higher than the baseline rate for sub-Saharan Africa and 1.4 times higher than the CMR cut-off point used to define excess mortality in emergencies. The current humanitarian response in Tete Province would benefit from an improved alignment of food aid programming in conjunction with diarrheal disease control, HIV/AIDS, and malaria prevention and treatment programs. The impact of the food programs would be improved if mutually acceptable food aid programme objectives, verifiable indicators relevant to each objective, and beneficiary targets and selection criteria are developed. Periodic re-assessments and evaluations of the impact of the program and evidenced-based decision-making urgently are needed to avert a chronic dependency on food aid.

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Background: The burden of breast cancer expressed in Disability Adjusted Life Years (DALYs) was compared for six European countries and its sensitivity to different sources of variation examined. Methods: DALYs were calculated using country-specific epidemiological data and European Disability Weights. Epidemiological data for 1996 were obtained for Denmark, England and Wales, France, the Netherlands, Spain and Sweden. Disability weights were empirically derived. Results:  Denmark and the Netherlands lost the largest number of DALYs (approximately 1100 DALYs per 100,000 women). They were followed by England (87% of the Danish burden), France (72%), Sweden (68%) and Spain (67%). 70 to 80% of the burden was caused by mortality. Cross-national variation in disease epidemiology was the largest source of variation in the burden of breast cancer. Variation in disability weights and uncertainty in epidemiological data had smaller effects. Conclusion: To compare the burden of breast cancer and most other types of cancer mortality rates provide sufficient information.