The effect of infection with Schistosoma margrebowiei on the growth of Bulinus natalensis

1993 ◽  
Vol 67 (1) ◽  
pp. 10-16 ◽  
Author(s):  
K. Raymond ◽  
A. J. Probert
Keyword(s):  
Growth Rate ◽  
Age Groups ◽  
Egg Laying ◽  
Uninfected Control ◽  
Control Groups ◽  
Post Exposure ◽  
Patent Infection

AbstractThree age groups of Bulinus natalensis, immature, mature but not yet egg-laying and mature egg-laying, were infected with miracidia of Schistosoma margrebowiei. The growth of infected, exposed but showing no signs of infection, and uninfected control groups, were examined at weekly intervals for ten weeks post exposure. Snails exposed to infection when immature, even in the group where no patent development ensued, showed a statistically significant reduction in growth and this was evident as early as 2–5 weeks post exposure. When infection occurred at the stage prior to egg-laying a significant reduction in growth was seen but only in the group which developed a patent infection. This was also the case for the egg-laying group although the reduction in growth was only significant in the final three weeks of the experiment. Thus in all three age groups, growth rate was reduced and the infected snails were significantly smaller at the end of ten weeks compared with the controls. The reasons for these effects are discussed.

The biology of Calocaris macandreae [Crustacea: Thalassinidea]

1963 ◽  
Vol 43 (3) ◽  
pp. 729-747 ◽  
Author(s):  
John B. Buchanan
Keyword(s):  
Growth Rate ◽  
Survival Curve ◽  
Age Groups ◽  
Larval Survival ◽  
Egg Laying ◽  
Moult Cycle ◽  
Size Frequency Distribution ◽  
Apparent Lack ◽  
Slowing Down ◽  
Population Numbers

Previous work on the biology and distribution of Calocaris is discussed briefly. The distribution in Northumberland waters is considered in relation to depth and bottom sediment.Quantitative monthly samples show that population numbers remain very stable throughout the year. A well marked egg-laying period occurs in January-February when relatively few eggs (average 38) are attached to the pleopods. Eggs are carried for 8–9 months and hatch in September-October. By a combination of size-frequency distribution and gonad-developmnt classification the age-groups in the population are interpreted. After passing through a phase of testes development and spermatophore formation individuals lay their first batch of eggs at the end of the 5th year. The ovaries regenerate over a 2-year period and a second egg-laying takes place at the end of the 7th year with a possible third at the end of the 9th year. The incidence of soft individuals in the samples together with observed changes in the coverage with epifaunistic growths indicate that after entering the 5th year a single annual moult cycle begins with a slowing down in growth rate.Population numbers, fecundity and larval survival are discussed. Both the survival curve and the apparent lack of serious predation suggest that the population reaches senescence

Time-Energy Budgets During Reproduction and the Evolution of Single Parenting in the Superb Lyrebird

1986 ◽  
Vol 34 (3) ◽  
pp. 351 ◽  
Author(s):  
A Lill
Keyword(s):  
Growth Rate ◽  
Brood Size ◽  
Slow Growth ◽  
Bird Species ◽  
Egg Laying ◽  
Energy Budgets ◽  
Brood Care ◽  
Single Parenting ◽  
Slow Growth Rate ◽  
Small Brood

Estimated expenditures on brood-care by unassisted female superb lyrebirds, obtained through time-energy budgeting, were compared with published values for other bird species. With the exception of nestbuilding, estimated daily expenditures were relatively low, due mainly to the small brood size and low level of parental attentiveness. It is suggested that the traits which reduce daily brood-care expenditures, particularly the small brood size and extremely slow growth rate, may have evolved as adaptations which enabled deserted females operating close to maximal capacity to cope with single-parenting. Male parental involvement could probably increase the growth rate of the young, but not brood size; moreover, egg- laying was sufficiently asynchronous to afford multiple mating opportunities to parentally emancipated males. However, the slow growth rate of the young results in relatively large overall brood-care expenditures for females. Investments by males of up to 50% of daylight hours and 45% of BMR on singing at the height of the mating season were comparable with those of partially emancipated, polygynous males of other species. They probably reflect the high level of competition to control good display areas and to advertise status and quality to widely spaced females.

scholarly journals Study the Oxidative Stress, Some Biochemical and Hematological Parameters in patients with agout at AL-Ramadi city

2016 ◽  
Vol 13 (4) ◽  
pp. 694-701
Author(s):  
Baghdad Science Journal
Keyword(s):  
Blood Cells ◽  
Hematological Parameters ◽  
Age Groups ◽  
Control Group ◽  
Enzymatic Antioxidants ◽  
Blood Picture ◽  
Control Groups ◽  
Blood Samples ◽  
Normal Individuals ◽  
And Control

This study aims to study the effect of gout disease on complete blood picture and biochemical parameters and some non-enzymatic antioxidants, some tracing elements and lipid peroxidation ,in outpatients with gout disease at Al-Ramadi Teaching-Hospital ,Al-Razi Hospital and the study duration from Octo.2013-to May 2014.(50) blood samples were collected from patients with age groups (30-80 years) from both sexes (28 males,22 females),a (30) blood samples (15 males,15 females) were collected from normal individuals as a control group with age groups (27-75 years). Hematological measurement showed no significant differences in size compressed blood cells, the percentages in ( 45.15 +4.99 and 46.87+6.30) % in patient and control groups respectively, hemoglobin concentrations were ( 14.04+1.66 and 14.30+1.93) g/l in patient and control groups respectively, total number of red blood cells ( 5.21+0.43 and 5.12 +0.58) 106/mm3 in patient and control groups respectively with(P?0.05) in ESR (21.06+13.47 and 13.37 +7.45) mm/hr in patient and control groups respectively with (P?0.05), the total number of WBCs were recorded (8.96+2.04 and 7.50+1.69)in patient and control groups respectively. Results showed also significant differences (P?0.05) in uric acid levels (7.42+0.76 and 5.62+0.88) mg/dl,malondialdehyde levels were recorded (4.45+0.64 and 3.21+0.86) in patient and control groups

Annual Productivity and Its Measurement in a Multi-Brooded Passerine, the Eastern Bluebird

The Auk ◽  
1979 ◽  
Vol 96 (3) ◽  
pp. 562-572
Author(s):  
Benedict C. Pinkowski
Keyword(s):  
Success Rate ◽  
Age Groups ◽  
Nesting Success ◽  
Egg Laying ◽  
Success Rates ◽  
Sialia Sialis ◽  
Eastern Bluebird ◽  
Annual Productivity ◽  
Eastern Bluebirds ◽  
Breeding Seasons

Abstract Breeding and demographic parameters are examined for 434 Eastern Bluebirds (Sialia sialis) attempting 324 nests in southeastern Michigan during 1968-1977. Nesting birds spent an average of 10.4 weeks (63.9% of a 16.2-week season) in the study area. Only 154 (35.5%) of the nesting birds remained for entire breeding seasons; these season-long residents averaged 2.14 nests/season and had a higher success rate (68.4%) and presumably greater productivity (5.6 young · pair−1 · season −1) than other birds because site fidelity depends on nesting success. Although two seasonal peaks for egg-laying were observed, only 75 of 357 birds (21.0%) successfully raised two broods. Evidence is presented to suggest that birds observed for only part of a season initiated nests at the same rate while in and not in the study area, so that an average annual productivity value of 5.0 young · pair−1 · season −1 is calculated for all nesting birds from the observed success rate (57.1%) and mean length of stay in the area. Estimated average productivity of yearlings (4.3 young · pair−1 · season −1) was lower than that of adults (5.7 young · pair−1 · season −1) although nesting success rates were similar in the two age groups.

The early bird catches the worm: age-specific arrival time influences reproductive performance in the White Stork Ciconia ciconia

Bird Study ◽  
2019 ◽  
Vol 66 (1) ◽  
pp. 121-129
Author(s):  
Bourhane-Eddine Belabed ◽  
Mohammed Athamnia ◽  
Laïd Touati ◽  
Farrah Samraoui ◽  
Abdennour Boucheker ◽  
...  
Keyword(s):  
Reproductive Performance ◽  
Age Groups ◽  
Egg Laying ◽  
White Stork ◽  
Laying Date ◽  
First Year ◽  
Arrival Date ◽  
Breeding Colony ◽  
Ciconia Ciconia ◽  
The Impact

<sec><title>Capsule</title>Age, arrival date and egg laying date are essentially closely related and determine reproductive performance in the White Stork Ciconia ciconia.</sec><sec><title>Aims</title>To describe the impact of age, arrival date and egg laying date on breeding success in the White Stork.</sec><sec><title>Methods</title>Ringing data from a White Stork breeding colony of 212 nests at Dréan, Algeria, were used to model the relationship between age, arrival date, laying date and reproductive performance. Seventy breeders that were individually colour-ringed as nestlings were monitored.</sec><sec><title>Results</title>Birds breeding on the periphery of the colony had significantly smaller nests and showed a tendency towards later laying dates, but they did not differ from centrally nesting birds in age or arrival date. First year birds did not breed and second year birds were significantly more likely than older age groups to occupy nests but fail to lay eggs. Older birds arrived earlier at the breeding colony and had a higher probability of initiating laying than younger birds. They also had a higher probability of nesting successfully and fledging a larger number of young.</sec><sec><title>Conclusion</title>Age determined arrival and laying dates and influenced breeding performance in the White Stork.</sec>

Factors influencing growth of juvenile spruce grouse

1981 ◽  
Vol 59 (9) ◽  
pp. 1790-1795 ◽  
Author(s):  
Norman W. S. Quinn ◽  
Daniel M. Keppie
Keyword(s):  
Growth Rate ◽  
Body Weight ◽  
New Brunswick ◽  
Growth Rates ◽  
Egg Laying ◽  
Maternal Influence ◽  
Juvenile Growth ◽  
Factors Influencing ◽  
Differential Timing

The influences of date of hatch, and age and prelaying body weight of brood female on the growth rate of juvenile spruce grouse (Canachites canadensis) were studied in central New Brunswick in 1977 and 1978. Because of differential timing of hatch of broods of adult and yearling females, it was not clear whether a difference in juvenile growth rates during 5–14 days of age in 1977 was related to date of hatch, age of brood female, or both. Differences in juvenile growth rates within and between years apparently were not influenced by body weight of brood females prior to egg laying. Results suggest that posthatch factors are more important in determining growth rate than a prehatch or "maternal" influence.

scholarly journals Evaluations of the Effects of Extremely Low-Frequency Electromagnetic Fields on Growth and Antibiotic Susceptibility ofEscherichia coliandPseudomonas aeruginosa

2012 ◽  
Vol 2012 ◽  
pp. 1-7 ◽  
Author(s):  
B. Segatore ◽  
D. Setacci ◽  
F. Bennato ◽  
R. Cardigno ◽  
G. Amicosante ◽  
...  
Keyword(s):  
Growth Rate ◽  
Electromagnetic Field ◽  
Electromagnetic Fields ◽  
Antibiotic Susceptibility ◽  
Low Frequency ◽  
Antibiotic Sensitivity ◽  
Control Groups ◽  
E Coli ◽  
Extremely Low Frequency ◽  
Number Of Cells

We aimed to investigate the effects of exposure to extremely low-frequency electromagnetic fields (2 mT; 50 Hz) on the growth rate and antibiotic sensitivity ofE. coliATCC 25922 andP. aeruginosaATCC 27853. The electromagnetic field treatment significantly influenced the growth rate of both strains when incubated in the presence of subinhibitory concentrations of kanamycin (1 μg/mL) and amikacin (0.5 μg/mL), respectively. In particular, at 4, 6, and 8 h of incubation the number of cells was significantly decreased in bacteria exposed to electromagnetic field when compared with the control. Additionally, at 24 h of incubation, the percentage of cells increased (P. aeruginosa∼42%;E. coli∼5%) in treated groups with respect to control groups suggesting a progressive adaptive response. By contrast, no remarkable differences were found in the antibiotic susceptibility and on the growth rate of both bacteria comparing exposed groups with control groups.

Limitations of the Single-Age Sample for Research on Birth Order

1980 ◽  
Vol 51 (3) ◽  
pp. 831-837 ◽  
Author(s):  
John N. McCall
Keyword(s):  
Growth Rate ◽  
Population Growth ◽  
Normal Distribution ◽  
Birth Order ◽  
Random Sample ◽  
Population Model ◽  
Population Growth Rate ◽  
Age Groups ◽  
Family Unit ◽  
Large Families

A simulated completed family population model was used to illustrate bias in single-age samples which results from changes in population growth rate. The model comprised 100 families or 238 individuals who ranged from 2 to 22 yr. in age. IQ-codes from a normal distribution were assigned to these individuals so that IQ correlated –.25 with family size and –.39 with occupational level. This produced a correlation of –.27 between birth order and IQ. A random sample, stratified random sample, and a random family unit sample estimated this last correlation quite closely. But estimates of this same correlation were spuriously high for 6 of the 11 single-age groups. These results were linked to an excess of early-borns in small families and an excess of later-borns in large families.

scholarly journals Lack of effect of supplementation with essential fatty acids on bone mineral density in healthy pre- and postmenopausal women:two randomized controlled trials of Efacal® v. calcium alone

2000 ◽  
Vol 83 (6) ◽  
pp. 629-635 ◽  
Author(s):  
E. Joan Bassey ◽  
Julie J. Littlewood ◽  
M. Claire Rothwell ◽  
David W. Pye
Keyword(s):  
Bone Turnover ◽  
Age Groups ◽  
Group Differences ◽  
Mineral Density ◽  
Control Groups ◽  
Treatment Groups ◽  
Markers Of Bone Turnover ◽  
Total Body ◽  
Age Range ◽  
And Control

Randomized controlled trials of the effects of the dietary supplement Efacal® (Scotia Pharmaceuticals Plc, Guildford, Surrey, UK) v. Ca only on total body bone mineral density (BMD) and markers of bone turnover were conducted in healthy pre- and postmenopausal women separately. Total daily dose for 12 months for the Efacal® groups was: Ca 1·0 g, evening primrose oil 4·0 g and marine fish oil 440 mg; and for the control groups was: Ca 1·0 g. Reported compliance was better than 90 % in both age groups. For the forty-three premenopausal women (age range 25–40 years), initial mean total body BMD values were similar for Efacal® and control groups and both groups showed highly significant mean increases of about 1 %; however, there were no significant between-group differences for the changes in BMD or markers of bone turnover. For the forty-two postmenopausal women (age range 50–65 years), initial mean total body BMD values were again well-matched across treatment groups. Both Efacal® and control groups showed highly significant decreases in total body BMD of about 1 %, but again there were no significant between-group differences in total body BMD or markers of bone turnover. Possible confounding variables such as initial total body BMD were explored but had no effect on the outcome in either age group. Nail quality improved in both age groups and in both Efacal® and control groups. Again, there was no significant difference between treatment groups. No evidence was found to support a beneficial effect of Efacal® on BMD in these women.

scholarly journals A Systematic Review and Meta-Analysis Estimating the Expected Dropout Rates in Randomized Controlled Trials on Yoga Interventions

2016 ◽  
Vol 2016 ◽  
pp. 1-7 ◽  
Author(s):  
Holger Cramer ◽  
Heidemarie Haller ◽  
Gustav Dobos ◽  
Romy Lauche
Keyword(s):  
Randomized Controlled Trials ◽  
Psychological Control ◽  
Age Groups ◽  
Dropout Rate ◽  
Health Condition ◽  
Dropout Rates ◽  
Cochrane Library ◽  
Controlled Trials ◽  
Control Groups ◽  
Randomized Controlled

A reasonable estimation of expected dropout rates is vital for adequate sample size calculations in randomized controlled trials (RCTs). Underestimating expected dropouts rates increases the risk of false negative results while overestimating rates results in overly large sample sizes, raising both ethical and economic issues. To estimate expected dropout rates in RCTs on yoga interventions, MEDLINE/PubMed, Scopus, IndMED, and the Cochrane Library were searched through February 2014; a total of 168 RCTs were meta-analyzed. Overall dropout rate was 11.42% (95% confidence interval [CI] = 10.11%, 12.73%) in the yoga groups; rates were comparable in usual care and psychological control groups and were slightly higher in exercise control groups (rate = 14.53%; 95% CI = 11.56%, 17.50%; odds ratio = 0.82; 95% CI = 0.68, 0.98;p=0.03). For RCTs with durations above 12 weeks, dropout rates in yoga groups increased to 15.23% (95% CI = 11.79%, 18.68%). The upper border of 95% CIs for dropout rates commonly was below 20% regardless of study origin, health condition, gender, age groups, and intervention characteristics; however, it exceeded 40% for studies on HIV patients or heterogeneous age groups. In conclusion, dropout rates can be expected to be less than 15 to 20% for most RCTs on yoga interventions. Yet dropout rates beyond 40% are possible depending on the participants’ sociodemographic and health condition.

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