The effect of other organisms on the survival rate of Aphodius tasmaniae Hope (Scarabaeidae) in the lower south east of South Australia.

1962 ◽  
Vol 10 (4) ◽  
pp. 617 ◽  
Author(s):  
DA Maelzer
Keyword(s):  
Survival Rate ◽  
High Mortality ◽  
South Australia ◽  
High Density ◽  
The Other ◽  
Low Density ◽  
Competition For Food ◽  
Lower South

The survival rate of the univoltine species Aphodius tasmaniae in improved pastures in the lower south-east of South Australia is influenced by individuals of the same species (i.e. by density) and by individuals of many other species. The species is distributed patchily with areas of high density interspersed with more extensive areas of low density. In the areas of high density, competition for food occurs and larvae may "fight". Such fights result in deaths, but there is little evidence of high mortality resulting from competition and little evidence that "density-induced combat" governs the number of the species. Of the other species which influence A. tasmaniae it is considered that the entomophagous fungus Cordyceps aphodii Mathieson is the only one which, in conjunction with water in winter, causes a sufficiently variable mortality from year to year to contribute significantly towards changes in numbers of A. tasmaniae from generation to generation.

scholarly journals A fencing experiment on a high-density population of Microtus townsendii

1977 ◽  
Vol 55 (7) ◽  
pp. 1166-1175 ◽  
Author(s):  
Rudy Boonstra ◽  
Charles J. Krebs
Keyword(s):  
Survival Rate ◽  
Breeding Season ◽  
Population Regulation ◽  
Control Area ◽  
High Density ◽  
Low Density ◽  
Vole Population ◽  
Sharp Decline ◽  
Density Population ◽  
Microtus Townsendii

If dispersal is prevented, a low-density vole population will increase to unusually high densities. A mouse-proof fence was constructed around a vole population that had already reached high density and both this population and one on a control area were live-trapped from January 1975 to November 1975. The population on the control remained at peak densities. The enclosed population increased to even higher density once the breeding season had started and had a higher survival rate than the control population. By midsummer the enclosed population had severely overgrazed the vegetation and went into a sharp decline. Dispersal losses from the control were estimated at 32% for males and 31% for females in these high-density populations. Microtus townsendii populations thus responded to a fence in a manner similar to that of other species that have been studied. This experiment indicates the importance of dispersal to population regulation in voles even at peak densities.

Ease of calving, growth and carcass characteristics of crossbred calves in the lower South East of South Australia

1983 ◽  
Vol 23 (122) ◽  
pp. 228 ◽  
Author(s):  
MPB Deland ◽  
RW Ponzoni ◽  
RW McNeil
Keyword(s):  
Growth Rate ◽  
Growth Rates ◽  
South Australia ◽  
Carcass Characteristics ◽  
The Other ◽  
Research Centre ◽  
Slaughter Cattle ◽  
Calf Mortality ◽  
Lower South ◽  
Jersey Cows

Hereford, Charolais and Brahman sires were mated to Hereford, Shorthorn, Jersey and Friesian xshorthorn cows for four successive years from June 1969 at Struan Research Centre in South Australia. Assistance was given during 15 .9% of calvings resulting from Charolais sires, 6.8% resulting from Brahman sires and 2.1% from Hereford sires (differences statistically significant, P < 0 05). A greater percentage of Friesian x Shorthorn (13.8) than of Shorthorn (5.0) or Jersey (4 3) cows were assisted at birth (P< 0.05). There were no significant differences between the percentage of Hereford cows assisted (10.9) and that of any of the other dam breeds. There were no significant differences in calf mortality among sire breeds or among dam breeds. Charolais-sired calves were heavier at birth, 270,340 and 430 d old and had heavier (1 95 kg) carcasses with a smaller proportion of fat than Brahman- and Hereford-sired carcasses (180 and 167 kg respectively) at 430d old. Brahman-sired calves were heavier than Hereford-sired calves at birth, 370, 430 d old. However, they were significantly lighter at 270 d old. Hereford cows gave birth to significantly heavier calves than Shorthorn and Jersey cows but there were no clear differences due to dam breed in growth rates of calves, carcass weights or composition. It was concluded that the use of Charolais sires in the lower South East of South Australia can result in significant increases in the growth rate of slaughter cattle and in the production of leaner carcasses. Brahman sires did not exhibit clear advantages over Hereford sires. No definite conclusions could be drawn about the dam breeds examined in the study.

scholarly journals Radio Recombination Lines from Starburst Galaxies: High and Low Density Ionized Gas

2002 ◽  
Vol 199 ◽  
pp. 243-244
Author(s):  
N.R. Mohan ◽  
K.R. Anantharamaiah ◽  
W.M. Goss
Keyword(s):  
Flux Density ◽  
Hii Regions ◽  
Starburst Galaxies ◽  
High Density ◽  
The Other ◽  
Low Density ◽  
Ionized Gas ◽  
Density Measurements ◽  
Radio Recombination Lines ◽  
Upper Limits

Radio recombination lines (RRL) at 8 GHz and 15 GHz detected from four starburst galaxies are shown to arise in compact high density HII regions, which are undetectable below ∼4 GHz. Detection of an RRL at 1.4 GHz towards one galaxy and upper limits in the other three are consistent with the presence of an equal amount of low density diffuse gas. Continuum flux density measurements using the GMRT will be important in constraining the properties of the diffuse gas.

Plant and animal responses of elephant grass pasture-based systems mixed with pinto peanut

2019 ◽  
Vol 157 (1) ◽  
pp. 63-71
Author(s):  
A. C. Vieira ◽  
C. J. Olivo ◽  
C. B. Adams ◽  
J. C. Sauthier ◽  
L. R. Proença ◽  
...  
Keyword(s):  
Crude Protein ◽  
Dry Matter ◽  
Nutritive Value ◽  
High Density ◽  
Forage Yield ◽  
The Other ◽  
Low Density ◽  
Elephant Grass ◽  
Herbage Yield ◽  
Grazing Systems

AbstractThe effects of growing pinto peanut mixed with elephant grass-based pastures are still little known. The aim of the current research was to evaluate the performance of herbage yield, nutritive value of forage and animal responses to levels of pinto peanut forage mass mixed with elephant grass in low-input systems. Three grazing systems were evaluated: (i) elephant grass-based (control); (ii) pinto peanut, low-density forage yield (63 g/kg of dry matter – DM) + elephant grass; and (iii) pinto peanut, high-density dry matter forage yield (206 g/kg DM) + elephant grass. The experimental design was completely randomized with the three treatments (grazing systems) and three replicates (paddocks) in split-plot grazing cycles. Forage samples were collected to evaluate the pasture and animal responses. Leaf blades of elephant grass and the other companion grasses of pinto peanut were collected to analyse the crude protein, in vitro digestible organic matter and total digestible nutrients. The pinto peanut, high-density dry matter forage yield + elephant grass treatment was found to give the best results in terms of herbage yield, forage intake and stocking rate, as well as having higher crude protein contents for both elephant grass and the other grasses, followed by pinto peanut with low-density forage yield + elephant grass and finally elephant grass alone. Better results were found with the grass–legume system for pasture and animal responses.

Effects of population density on female and male burrow characteristics in the fiddler crab, Uca bengali Crane, 1975

Crustaceana ◽  
2015 ◽  
Vol 88 (12-14) ◽  
pp. 1283-1299 ◽  
Author(s):  
Fahmida Wazed Tina ◽  
Mullica Jaroensutasinee ◽  
Krisanadej Jaroensutasinee
Keyword(s):  
Body Size ◽  
Population Density ◽  
Fiddler Crab ◽  
High Density ◽  
The Other ◽  
Low Density ◽  
Density Effects ◽  
Egg Incubation ◽  
Other Hand ◽  
Males And Females

We examined the effects of population density on body size and burrow characteristics ofUca bengaliCrane, 1975. We predicted that (1) males in high-density areas (HD) should be larger in size and build higher quality burrows than males in low-density areas (LD), and (2) HD females should be larger in size, but build lower quality burrows than LD females, as HD females can find higher numbers of good quality male burrows around them for breeding and egg incubation. Our results showed that males and females in HD were larger in size than those in LD. Since HD males were larger in size, they built higher quality burrows than males in LD. On the other hand, even though LD females were smaller in size than HD ones, they built higher quality burrows than HD females. Our results thus indicate that density effects both body size and burrow characteristics.

An experimental study of the behavior of blue grouse (Dendragapus obscurus). I. Differences between the founders from three populations

1975 ◽  
Vol 53 (9) ◽  
pp. 1222-1237 ◽  
Author(s):  
Arthur T. Bergerud ◽  
H. Dennis Hemus
Keyword(s):  
Vancouver Island ◽  
Mirror Image ◽  
High Density ◽  
The Other ◽  
Low Density ◽  
Single Population ◽  
High Density Population ◽  
Dendragapus Obscurus ◽  
Field Workers ◽  
Density Population

In 1970 the authors compared the behavior of two low-density populations of blue grouse (Dendragapus obscurus) with the behavior of a high-density population on Vancouver Island. They then introduced individuals from these populations onto four islands and compared the behavior of these founders in 1971 and 1972.One island received founders from all three populations, while the other three islands each received founders from a single population. Birds from two low-density populations were quite observable, and displayed frequently when approached by field workers, both at their capture sites on Vancouver Island and in different habitats on the release sites on islands. The high-density population was much less observable, and displayed less frequently than did the two low-density populations, both at the capture sites and on the release islands. Male founders from the low-density populations were more aggressive in interacting with their mirror image than were males from the high-density population. Male founders from the high-density population dispersed less from the release sites, had smaller territories, and settled closer together than did males from the two low-density populations. These findings are consistent with the view that animals have a form of behavior that spaces them out as numbers rise, and so prevents unlimited increase in numbers.

Survival and fertility of bitches undergoing caesarean section

2019 ◽  
Vol 186 (13) ◽  
pp. 416-416
Author(s):  
Theresa Conze ◽  
Andrzej Jurczak ◽  
Vanessa Fux ◽  
Piotr Socha ◽  
Axel Wehrend ◽  
...  
Keyword(s):  
Survival Rate ◽  
Mortality Rate ◽  
Caesarean Section ◽  
High Mortality ◽  
Survival Rates ◽  
Fertility Rate ◽  
The Other ◽  
Medical Indication ◽  
Other Hand ◽  
Overall Mortality

BackgroundWith the increasing popularity of planned caesarean section, the need for knowledge regarding this surgery has become increasingly important. The reported death and survival rates for caesarean sections vary widely. Another important aspect is the fertility rate in subsequent oestrous after caesarean section. The aim of this study was to investigate the mortality and survival rate of bitches during caesarean section. Additionally, the fertility of bitches after caesarean sections was determined.MethodsCaesarean sections which were performed in the years 1997–2009 at two university clinics were evaluated retrospectively. A distinction was made between bitches in which a conservative caesarean section was performed and bitches with a caesarean section followed by an ovariohysterectomy.ResultsA total of 482 caesarean sections were included in the study. The overall mortality rate was 3.11 per cent, with 2.59 per cent during or after a conservative caesarean section and 4.19 per cent during or after caesarean section with ovariohysterectomy. The reason for ovariohysterectomy was the owner’s preference in 63 bitches (47.01 per cent); in 71 (52.98 per cent) bitches, ovariohysterectomy was performed due to a medical indication. The fertility rate after caesarean section was 100 per cent.ConclusionThe results show a high mortality rate during and after caesarean section. On the other hand, caesarean section does not seem to have a big impact on further fertility. Further studies are needed to investigate possible reduction of litter sizes and the suitability of caesarean section in subsequent pregnancies.

Rainfall and changes in abundance of Aphodius tasmaniae Hope (Coleoptera: Scarabaeidae) in the lower south-east of South Australia.

1964 ◽  
Vol 12 (2) ◽  
pp. 263 ◽  
Author(s):  
DA Maelzer
Keyword(s):  
Experimental Data ◽  
Marked Reduction ◽  
Birth Rate ◽  
Pathogenic Fungus ◽  
South Australia ◽  
The Other ◽  
Critical Periods ◽  
First Instar ◽  
Lower South ◽  
Low Birth Rate

This paper discusses the causes of three "outbreaks" of the univoltine species, A. tasmaniae, that occurred in the lower south-east of South Australia between 1927 and 1958. Since experimental data had suggested that moisture was the major factor influencing fluctuations in numbers, a comparison was made of the abundance of A. tasmaniae and the "wetness" in each year during three postulated critical periods, namely (1) January-March (summer) when a deficiency of rain could result in a low birth rate; (2) March-May (autumn) when drought could result in a high mortality of first instar larvae; and (3) July-September (winter), when excess rainfall could drown the larvae or promote infection with the pathogenic fungus Cordyceps aphodii Mathieson. The comparison suggested that a marked reduction in numbers followed a long autumn drought on one occasion, and followed a summer with little effective rain on three other occasions; but a reduction in numbers could not be associated clearly with even one wet winter. On the other hand, the greatest increases in numbers followed winters that were drier than average, provided that the weather was not too unfavourable at other times of the year; and the periods of 4 years before each outbreak were noticeable for the unusual prevalence of dry winters and wet summers. It is concluded that the fluctuations in numbers of A. tasmaniae between 1927 and 1958 have been determined largely by weather and by Cordyceps infection.

Biochemical Changes in Mild Hypothyroidism and its Affiliation with Dyslipidemia in Pakistan

2021 ◽  
Vol 15 (9) ◽  
pp. 2890-2892
Author(s):  
Ayesha Zubair ◽  
Sabahat Fatima ◽  
Saleha Akram , Nizami ◽  
Anas Khalil ◽  
Rabia Sattar ◽  
...  
Keyword(s):  
Thyroid Function ◽  
Low Density Lipoprotein ◽  
Density Lipoprotein ◽  
High Density ◽  
The Other ◽  
Medical Society ◽  
Low Density ◽  
Group I ◽  
Lipid Abnormalities ◽  
Mild Hypothyroidism

Background: Primary hypothyroidism is associated with the synthesis, metabolism and lipid abnormalities of thyroid hormones. Individuals with hypothyroidism have been shown to have high low density cholesterol and low high density cholesterol. In individuals with normal thyroid the association is usually observed between total cholesterol and thyroid stimulating hormone. Due to lipid abnormalities one group of experts is of the opinion that individuals with TSH ≤10 mIU/L having features of hypothyroidism should be started with thyroxine medication. Whereas, the other group does not support this idea making the topic controversial. In Pakistan the association between thyroid function and lipid abnormalities have so far not been studied which leaves a room for research at this topic. Aim: To explore the association between mild hypothyroidism and lipid abnormalities in Pakistani population. Methodology: This cross sectional study is carried out at Alfalah Welfare Medical Society, Lahore as part of their medical checkup, all the subjects gave written informed consent. The study was done from January 2021 to July 2021. Results: Thyroid function test of 2312 (85.4%) of the subjects was found to be normal. Subjects with mild hypothyroidism among Group-I were 324 (11.9%) whereas mild hypothyroidism in group-II were 36(1.3%). Triglyceride (3.99±0.80 compared to 3.79±0.70 mmol/L, p˂0.0001), low density lipoprotein (2.59±0.60 compared to 2.29±0.39mmol/L, p˂0.0001) and high density lipoprotein was (1.10±0.14 compared to 1.14±0.15 mmol/L). Conclusion: In patients with mild hypothyroidism due to deranged lipid profile atherogenesis was observed. In continuation to it low high density lipoproteins were also observed in children and a raised triglyceride and low density lipoprotein in the adult population. On the other hand, in patients with mild hypothyroidism having low TSH levels no such abnormalities were observed. Keywords: Dyslipidemia, Subclinical Hypothyrodism, Thyroid

Distribution and abundance of the feral camel (Camelus dromedarius) in Australia

2010 ◽  
Vol 32 (1) ◽  
pp. 1 ◽  
Author(s):  
W. K. Saalfeld ◽  
G. P. Edwards
Keyword(s):  
South Australia ◽  
Northern Territory ◽  
High Density ◽  
The Other ◽  
Population Estimate ◽  
Sandy Desert ◽  
High Density Area ◽  
Current Minimum ◽  
Simpson Desert ◽  
A Current

In this paper we utilised a range of data sources to estimate the extent, density distribution and population size of the feral camel in Australia in 2008. Camels currently occupy 3.3 million km2 and are spread across much of arid Western Australia, South Australia, the Northern Territory and far western Queensland. Up to 50% of Australia’s rangelands are reported as having camels present. The research reported here supports a current minimum population estimate for the feral camel in Australia of ~1 million animals at an overall density of 0.29 camels/km2. Densities vary, and the modelling of available data indicates that two substantial areas of high density are present, one centred on the Simpson Desert and the other on the Great Sandy Desert. The high density area covering the eastern part of the Great Sandy Desert has predicted densities in the range of 0.5 to >2 animals/km2 whereas that on the Simpson Desert is in the range 0.5–1.0 animals/km2.

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