Trichostrongylid infections of sheep in a winter rainfall region. II. Epizootiological studies in the western district of Victoria, 1967-68

1973 ◽  
Vol 24 (4) ◽  
pp. 599 ◽  
Author(s):  
N Anderson
Keyword(s):  
Weather Conditions ◽  
Mucosal Damage ◽  
Anthelmintic Treatment ◽  
Free Living ◽  
Winter Rainfall ◽  
Wool Production ◽  
Adult Sheep ◽  
The Relationship ◽  
Region Ii ◽  
Rainfall Region

Mean counts of O. circumcincta and Trichostrongylus spp. from groups of 'tracer' sheep ranged between 220 and 2150 per fortnight between June and October and were less than 100 per fortnight from November to February inclusive. O. circumcincta was more numerous than Trichostrongylus spp. The relatively low numbers of available larvae were attributed to the dry weather conditions in autumn which did not favour development and survival of the free-living stages. Between May and December 1967, worm numbers increased linearly in weaner sheep to reach mean levels of 14,000 without any detectable resistance to reinfection or significant decrease in liveweight gain or wool production. Correlations between mean plasma pepsinogen concentrations from weaner and adult sheep and 'tracer' worm burdens were significantly different; r = 0.37 and 0.47 for weaners and r = 0.8 for adult sheep. Thus the relationship between larval intake and abomasal damage as reflected by plasma pepsinogen concentrations is not a simple one. Mucosal damage is probably preceded by a hypersensitive state. Anthelmintic treatment, given in October and January, reduced the worm egg output of treated sheep to one-tenth that of untreated sheep for a period of 18 weeks between October and March.

Populations of free-living stages of Ostertagia ostertagi and O. circumcincta in a winter rainfall region

1983 ◽  
Vol 34 (5) ◽  
pp. 569 ◽  
Author(s):  
RR Young
Keyword(s):  
Population Dynamics ◽  
Survival Rate ◽  
Larval Survival ◽  
Moisture Loss ◽  
Free Living ◽  
Winter Rainfall ◽  
Faecal Pellets ◽  
Infective Larvae ◽  
Cattle Faeces ◽  
Rainfall Region

Pats of cattle faeces containing eggs of the trichostrongylid Osferfagia ostertagi and deposits of sheep faecal pellets containing eggs of O. circumcincta were placed on dry and irrigated pasture plots at four times during the period October 1977 to February 1978. Faecal pellets lost moisture far more rapidly than did dung pats. The rate of moisture loss from both faecal deposits was greater on dry plots than on irrigated plots. Despite large differences between irrigated and dry plots in soil temperature and soil and pasture moisture status, the temperatures recorded in both dung pats and faecal pellets were similar on all plots at each time of deposition. A significantly greater proportion of O . circumcincta eggs was recovered as infective larvae in faeces, on herbage and in soil compared with that of O. osterfagi eggs. Irrigation did not result in either substantially more eggs developing to infective larvae in faeces or higher recoveries of larvae from herbage and soil. No significant differences were detected in temperature or moisture measurements or in parameters of free-living development and larval survival between plots with long or short pasture herbage. There were marked differences between the population dynamics of the infective larvae of Ostertagia spp. and between the numbers of larvae on irrigated and dry plots. On dry plots, O . circumcincta migrated in abundance from faecal deposits after smaller falls of rain than were required for migration of O . ostertagi larvae. Larvae of both species persisted in abundance on the herbage of most dry plots until late spring. On irrigated plots, migration of both species of larvae occurred immediately and was independent of rainfall, but survival rate of larvae was lower than on the corresponding dry plots.

Intraspecific variation in the relationship between weather and masting behavior in valley oak, Quercus lobata

2020 ◽  
Vol 50 (12) ◽  
pp. 1299-1306
Author(s):  
Walter D. Koenig ◽  
Johannes M.H. Knops ◽  
William J. Carmen
Keyword(s):  
Seed Production ◽  
Pollen Limitation ◽  
Weather Conditions ◽  
Quercus Petraea ◽  
Weather Factors ◽  
Acorn Production ◽  
Winter Rainfall ◽  
Quercus Lobata ◽  
Valley Oak ◽  
The Relationship

Masting behavior — variable and synchronized reproduction by a population of plants — has long been recognized as correlating with weather. How and why weather conditions influence seed production is, however, poorly understood. We investigated the relationships between acorn production and both local weather and long-term climate in 10 populations across the geographic range of the valley oak (Quercus lobata Née), a California endemic that matures acorns in a single season. Acorn production was larger following a cold spring in the prior year and dry conditions in the winter and spring immediately preceding acorn maturation; similar patterns were also found, with minor differences, at all 10 individual sites. The strength of the relationships varied geographically in the case of the correlation between winter rainfall and annual acorn production, which was stronger (more negative) at wetter sites. Thus, in contrast to a recent study in Quercus petraea (Matt.) Liebl., weather had generally similar effects on acorn production throughout the range of Q. lobata. Similar to Q. petraea, however, the strength of the relationship between site-level annual acorn production and one of the weather factors affecting acorn production (winter rainfall in the case of Q. lobata) varied geographically in ways that may be related to differences among sites in the degree of pollen limitation. Understanding the mechanisms by which weather affects seed production is challenging but critical if we are to understand how climate change will affect masting behavior in the future.

Observations on the development and survival of the free-living stages of Oesophagostomum dentatum both in their natural environments out-of-doors and under controlled conditions in the laboratory

Parasitology ◽  
1980 ◽  
Vol 81 (3) ◽  
pp. 507-517 ◽  
Author(s):  
J. H. Rose ◽  
A. J. Small
Keyword(s):  
Weather Conditions ◽  
Early Spring ◽  
Climatic Conditions ◽  
Natural Environments ◽  
Free Living ◽  
Infective Larvae ◽  
Oesophagostomum Dentatum ◽  
Wide Range ◽  
Dry Out ◽  
The Relationship

SUMMARYEggs of Oesophagostomum dentatum in faeces deposited on grass plots from May to October developed into infective larvae. Warm wet weather facilitated development but weather conditions which caused the faeces to dry out rapidly resulted in a heavy mortality of eggs and pre-infective larvae. During the winter no development took place and the eggs died. In the early spring and late autumn a few eggs survived and developed into 1st-stage larvae but they died without developing further. In the laboratory no development took place at 4 °C but at temperatures ranging from 10 to 25 °C development into infective larvae was completed, the rate increasing as the temperature rose. Out-of-doors infective larvae survived in faeces and on herbage for 1 year under a wide range of climatic conditions including the exceptionally cold winter of 1978–79. In the laboratory, infective larvae suspended in water survived even longer at temperatures ranging from 4 to 27 °C. They were rapidly killed by continuous freezing and by desiccation when the relative humidity was less than 90%. The relationship between climatic conditions and the development and survival of the free-living stages is discussed.

scholarly journals Fail to Yield? An Analysis of Ambulance Crashes in Taiwan

2021 ◽  
Vol 13 (3) ◽  
pp. 1566
Author(s):  
Rong-Chang Jou ◽  
Ming-Che Chao
Keyword(s):  
Public Education ◽  
Weather Conditions ◽  
Medical Emergency ◽  
Transportation Safety ◽  
Emergency Vehicle ◽  
The Road ◽  
Mnl Model ◽  
On The Road ◽  
Crash Injuries ◽  
The Relationship

Introduction—Medical emergency vehicles help patients get to the hospital quickly. However, there were more and more ambulance crashes on the road in Taiwan during the last decade. This study investigated the characteristics of medical emergency vehicle crashes in Taiwan from January 2003 to December 2016. Methods—The ordered logit (OL) model, multinominal logit (MNL) model, and partial proportional odds (PPO) model were applied to investigate the relationship between the severity of ambulance crash injuries and its risk factors. Results—We found the various factors have different effects on the overall severity of ambulance crashes, such as ambulance drivers’ characteristics and road and weather conditions. When another car was involved in ambulance crashes, there was a disproportionate effect on the different overall severity, as found by the PPO model. Conclusions—The results showed that male ambulance drivers and car drivers who failed to yield to an ambulance had a higher risk of severe injury from ambulance crashes. Ambulance crashes are an emerging issue and need further policies and public education regarding Taiwan’s ambulance transportation safety.

scholarly journals It’s the Weather: Quantifying the Impact of Weather on Retail Sales

2021 ◽  
Author(s):  
Natalie Rose ◽  
Les Dolega
Keyword(s):  
Weather Condition ◽  
Weather Conditions ◽  
Influential Factor ◽  
Retail Sector ◽  
Retail Sales ◽  
Weather Impact ◽  
High Street ◽  
Sector Decision ◽  
The Impact ◽  
The Relationship

AbstractThe weather is considered as an influential factor on consumer purchasing behaviours and plays a significant role in many aspects of retail sector decision making. As a result, better understanding of the magnitude and nature of the influence of variable UK weather conditions can be beneficial to many retailers and other stakeholders. This study addresses the dearth of research in this area by quantifying the relationship between different weather conditions and trading outcomes. By employing comprehensive daily sales data for a major high street retailer with over 2000 stores across England and adopting a random forest methodology, the study quantifies the influence of various weather conditions on daily retail sales. Results indicate that weather impact is greatest in the summer and spring months and that wind is consistently found to be the most influential weather condition. The top five most weather-dependent categories cover a range of different product types, with health foods emerging as the most susceptible to the weather. Also, sales from out-of-town stores show a far more complex relationship with the weather than those from traditional high street stores with the regions London and the South East experiencing the greatest levels of influence. Various implications of these findings for retail stakeholders are discussed and the scope for further research outlined.

Occurrence of putatively resistant plantago in the winter rainfall region of South Africa: a survey

2021 ◽  
Vol 38 (5) ◽  
pp. 411-415
Author(s):  
Vhuthu Ndou ◽  
Ethel E Phiri ◽  
Frederik H Eksteen ◽  
Petrus J Pieterse
Keyword(s):  
South Africa ◽  
Winter Rainfall ◽  
Rainfall Region

scholarly journals Objective measurement of physical activity in Macaca fascicularis

1982 ◽  
Vol 16 (3) ◽  
pp. 240-243
Author(s):  
Wayne T. Corbett ◽  
Harry M. Schey ◽  
A. W. Green
Keyword(s):  
Physical Activity ◽  
Standard Deviation ◽  
Macaca Fascicularis ◽  
Living Environment ◽  
Activity Levels ◽  
Free Living ◽  
Activity Measurements ◽  
Active Intermediate ◽  
The Mean ◽  
The Relationship

The mean and standard deviation over 24 h for 3 groups of animals - active, intermediate and inactive - in physical activity units were 10948 ± 3360, 2611 ± 1973 and 484 ± 316 respectively. The differences were significant ( P = 0·004), demonstrating the ability of the method to distinguish between groups that can be visibly differentiated. The small within-animal physical activity standard deviation (18·85 PAU) obtained in another group, suggests that it also yields reliable physical activity measurements for non-human primates. The monitoring device used can discriminate between individual nonhuman primate physical activity levels in a free-living environment and does not alter daily behaviour. This makes possible the study of the relationship between physical activity and atherosclerosis in nonhuman primates.

scholarly journals Exploring the relation between aerosol optical depth and PM<sub>2.5</sub> at Cabauw, the Netherlands

2008 ◽  
Vol 8 (5) ◽  
pp. 17939-17986 ◽  
Author(s):  
M. Schaap ◽  
A. Apituley ◽  
R. M. A. Timmermans ◽  
R. B. A. Koelemeijer ◽  
G. de Leeuw
Keyword(s):  
The Netherlands ◽  
Ground Level ◽  
Weather Conditions ◽  
Fair Weather ◽  
Modis Aod ◽  
Data Points ◽  
Set Up ◽  
The Relationship ◽  
Lidar Observations ◽  
Pm2.5 Concentration

Abstract. To acquire daily estimates of PM2.5 distributions based on satellite data one depends critically on an established relation between AOD and ground level PM2.5. In this study we aimed to experimentally establish the AOD-PM2.5 relationship for the Netherlands. For that purpose an experiment was set-up at the AERONET site Cabauw. The average PM2.5 concentration during this ten month study was 18 μg/m3, which confirms that the Netherlands are characterised by a high PM burden. A first inspection of the AERONET level 1.5 (L1.5) AOD and PM2.5 data at Cabauw showed a low correlation between the two properties. However, after screening for cloud contamination in the AERONET L1.5 data, the correlation improved substantially. When also constraining the dataset to data points acquired around noon, the correlation between AOD and PM2.5 amounted to R2=0.6 for situations with fair weather. This indicates that AOD data contain information about the temporal evolution of PM2.5. We had used LIDAR observations to detect residual cloud contamination in the AERONET L1.5 data. Comparison of our cloud-screed L1.5 with AERONET L2 data that became available near the end of the study showed favorable agreement. The final relation found for Cabauw is PM2.5=124.5*AOD–0.34 (with PM2.5 in μg/m3) and is valid for fair weather conditions. The relationship determined between MODIS AOD and ground level PM2.5 at Cabauw is very similar to that based on the much larger dataset from the sun photometer data, after correcting for a systematic overestimation of the MODIS data of 0.05. We applied the relationship to a MODIS composite map to assess the PM2.5 distribution over the Netherlands. Spatial dependent systematic errors in the MODIS AOD, probably related to variability in surface reflectance, hamper a meaningful analysis of the spatial distribution of PM2.5 using AOD data at the scale of the Netherlands.

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