Reproduction, Growth and Mortality of Venus Striatula (Da Costa) in Kames Bay, Millport

1961 ◽  
Vol 41 (1) ◽  
pp. 191-215 ◽  
Author(s):  
Alan D. Ansell
Keyword(s):  
Sex Ratio ◽  
Microscopic Examination ◽  
Seasonal Changes ◽  
One Year

Seasonal changes in the gonads of both sexes of Venus striatula were followed by macroscopic and microscopic examination, in over 700 animals from a population consisting mainly of one year-group. The sex ratio was approximately equal, and no hermaphrodite adults were found.

Age, Growth and Sex Ratio of the Azorean Rock-Pool Blenny, Parablennius Sanguinolentus Parvicornis

1995 ◽  
Vol 75 (3) ◽  
pp. 751-754 ◽  
Author(s):  
Ricardo Serrão Santos ◽  
Richard D. M. Nash ◽  
Stephen J. Hawkins
Keyword(s):  
Sex Ratio ◽  
Growth Function ◽  
Early Growth ◽  
Reproductive Season ◽  
First Year ◽  
Von Bertalanffy ◽  
Rock Pool ◽  
Total Length ◽  
Von Bertalanffy Growth Function ◽  
One Year

The age and population structure of Parablennius sanguinolentus parvicornis (Valenciennes) (Pisces: Blenniidae) from the Azores have been studied. Total length and weight relationships are given for each sex. Age study was based on otoliths readings. The von Bertalanffy growth function was applied to describe the growth in total length with age. At the end of the first year mean (±SD) total length was significantly different in males (7.1 ±1.5 cm) and females (6.1 ±1.2 cm). One-year-old males participate in reproduction as satellites, whereas females do not. The implications of this in early growth rate of the males is discussed. During the two most important months of the reproductive season (i.e. June and July), the sex ratio was significantly biased towards males, particularly in the larger size classes.

scholarly journals Population structure and reproductive characteristics of the silky shark Carcharhinus falciformis (Müller & Henle, 1839) (Carcharhiniformes: Carcharhinidae) off the coast of Oaxaca, Mexico

2017 ◽  
Vol 44 (3) ◽  
pp. 513-524
Author(s):  
María del Carmen Alejo-Plata ◽  
Miguel Ángel Ahumada-Sempoal ◽  
José Luis Gómez-Márquez ◽  
Adrián González-Acosta
Keyword(s):  
Population Structure ◽  
Sex Ratio ◽  
Seasonal Changes ◽  
Sexual Maturity ◽  
Size Structure ◽  
Landing Sites ◽  
Silky Shark ◽  
Oceanic Species ◽  
Carcharhinus Falciformis ◽  
Gravid Females

Carcharhinus falciformis is an abundant oceanic species, which occurs in equatorial and tropical zones, with an important catch in the Atlantic and Pacific coasts of Mexico. Samples were taken from December 2000 to December 2007 in four landing sites of the artisanal fleet on the coast of Oaxaca. During the period of study 1236 specimens (602 females and 634 males) of C. falciformis were registered. Total length (TL) ranged from 49 to 217 cm for females (mean = 111.3 cm) and from 59 to 265 cm for males (mean = 111.7 cm). The sex ratio of females to males was 1:1 ( 2 0.05 = 0.78, P > 0.05). The present data suggest a size at first sexual maturity of about 184.8 cm TL for females and 178.5 cm TL for males. The catches were composed mainly of young. In the 52 gravid females examined, the average number of embryos per female was seven; with a range of 3-14 embryos. Mean TL of embryos ranged from 10 to 66 cm with evidence of seasonal changes in the size structure. Results obtained showed that C. falciformis gives birth most of the year, with the highest proportion of births during the rainy season (May to October).

Health, growth and development of pre-school children in Newcastle upon Tyne

1979 ◽  
Vol 11 (4) ◽  
pp. 411-424
Author(s):  
H. Mary Fellowes ◽  
Catherine A. Hytten ◽  
W.Z. Billewicz ◽  
A.M. Thomson
Keyword(s):  
Growth Rates ◽  
Seasonal Changes ◽  
Growth Patterns ◽  
Transient Effect ◽  
Normal Children ◽  
Average Growth ◽  
Respiratory Illnesses ◽  
Developmental Test ◽  
One Year ◽  
Newcastle Upon Tyne

SummaryOne hunderd and forty 'normal' children aged 0—5 years, selected from three large general medical practices to represent a wide socioeconomic range, were seen monthly for periods of at least one year. Average growth patterns, previously shown to be related to the energy value of diets, conformed to British standards. Height and weight were not significantly related to socioeconomic status, maternal 'efficiency', number of sibs nor place in family. About half the children aged 0.5 years or less changed growht 'channels', falling to 0.4% in children aged 2 years or more. Respiratory illnesses showed seasonal changes, but growth rates did not, and there was no evidence that illness of any kind or severity had more than a transient effect on growth rates. Developmental test scores were not found to be related to growth rates. Girls tended to have higher scores than boys. Children from non-manual families and those with sїbs at least 5 years older scored more highly in tests of language than those in other types of family.

Seaweed-associated animal communities in the Firth of Clyde, with special reference to the population biology of the amphipod Hyale nilssoni (Rathke)

1986 ◽  
Vol 90 ◽  
pp. 271-286
Author(s):  
P. G. Moore
Keyword(s):  
Growth Rate ◽  
Life History ◽  
Sex Ratio ◽  
Seasonal Changes ◽  
Population Biology ◽  
Dynamic Equilibrium ◽  
Present Knowledge ◽  
New Work ◽  
Animal Communities ◽  
Breeding Status

SynopisPresent knowledge of animal communities associated with the algae of the Firth of Clyde is briefly reviewed. New work is presented on Hyale nilssoni (Rathke), the commonest amphipod inhabiting high littoral seaweeds, which describes the life-history characteristics over three years of a population associated with Pelvetia. Seasonal changes in growth rate, sex ratio and breeding status are described. Fecundity is investigated and data on brood and egg sizes compared with populations from other latitudes. The dynamic equilibrium between the grazer (Hyale) and the grazed (Pelvetia) is described.

Sex Ratio of Sea Turtles: Seasonal Changes

Science ◽  
1984 ◽  
Vol 225 (4663) ◽  
pp. 739-741 ◽  
Author(s):  
N. MROSOVSKY ◽  
S. R. HOPKINS-MURPHY ◽  
J. I. RICHARDSON
Keyword(s):  
Sex Ratio ◽  
Seasonal Changes ◽  
Sea Turtles

scholarly journals Seasonal changes in size, sex-ratio and body condition of the damselfishChromis chromisin the central Mediterranean Sea

2014 ◽  
Vol 94 (5) ◽  
pp. 1053-1061 ◽  
Author(s):  
Claudia Bracciali ◽  
Susanna Piovano ◽  
Gianluca Sarà ◽  
Cristina Giacoma
Keyword(s):  
Population Structure ◽  
Sex Ratio ◽  
Body Condition ◽  
Seasonal Changes ◽  
Marine Protected Area ◽  
Reproductive Period ◽  
Rocky Shores ◽  
Central Mediterranean ◽  
Monthly Basis ◽  
Spawning Period

Chromis chromisis one of the most abundant fish species on the Mediterranean rocky shores. Acting as a by-pass of nutrients from the pelagic to the rocky littoral system, it plays an important role as a resource provider and has a relevant function in the community assemblage.Chromis chromishas many of the characteristics required of an indicator species (e.g. it is easy to recognize in the field, small sized, widespread and abundant). In this study we focused on individual size, sex-ratio and body condition in a damselfish population occurring in a central Mediterranean marine protected area. Fishing trials on a monthly basis (April–November) allowed us to assess seasonal changes in population structure. Fish were measured and weighed and a subsample was aged and sexed. On average, males were larger than females. The allometric coefficient,b, for the whole population was 2.99; the maximum age recorded was 7.5 yr. Before reproduction sex-ratio was close to parity (M:F 1:0.78), while a larger proportion of females was captured during the reproductive period. In conclusion, our results show that the population dynamics ofC. chromisis influenced by both sex and size. Since males and females have different behavioural strategies, and since the length of the spawning period is shorter in the smaller than in the larger-sized individuals, this is reflected in temporal changes observed in the population structure.

scholarly journals Prevalence and Public Health Importance of Hydatidosis in Sheep Slaughtered by Unlicensed Ways

2019 ◽  
Vol 12 (1) ◽  
pp. 399-402 ◽  
Author(s):  
Fadia Abd Al-Muhsin Al-Khayat
Keyword(s):  
Public Health ◽  
Microscopic Examination ◽  
Prevalence Rate ◽  
Parasitic Disease ◽  
Public Health Importance ◽  
Age And Gender ◽  
Control Programs ◽  
And Gender ◽  
One Year ◽  
The Relationship

Hydatidosis is a zoonotic, helminthes parasitic disease that cause veterinary and human problems due to economic burden. Amis of the current study was to estimate the prevalence rate of hydatidosis infecting different organs of sheep slaughtered in street. In addition, investigate the relationship between age, gender and the infected rates in some Baghdad areas during a period from may to end of July 2018.A total of 188 sheep was examined for detection of Hydatid cyst in different organs using macroscopic and microscopic examination The overall prevalence rate of 47.9% was recorded. The results indicate non significant differences according to age and gender, the highest rate 57% was observed in sheep more than one year old compared with small ages 31.3%. The females showed the highest rate 59.3% while the male recorded 30.7%. The most affected organ was the liver 64.4% followed by the lung 25.6% and finally the spleen 10%. Conclusion of this study indicates the higher prevalence rate lead to the necessity for control programs against hydatidosis includ preventing of illegal slaughtering.

The Tasmanian Whitebait, Lovettia seali (Johnston), and the Whitebait Fishery

1950 ◽  
Vol 1 (2) ◽  
pp. 155 ◽  
Author(s):  
M Blackburn
Keyword(s):  
Growth Rate ◽  
Sexual Dimorphism ◽  
Sex Ratio ◽  
Incubation Period ◽  
Standard Length ◽  
Southern Population ◽  
History Of ◽  
One Year

The biology of the aplochitonid Lovettia seali (Johnston), which comprises over 95 per cent. of the Tasmanian whitebait catch, has been studied. Over 78,000 fish from 95 samples were sexed and measured, and 1,200 were classified as to maturity, pigmentation stages, and the presence or absence of food in the stomach. Vertebra counts were made for 1,200 specimens, and there were other observations upon smaller amounts of material. There are marked resemblances to other salmonoids in most points of the biology. There is conspicuous sexual dimorphism. The fish are anadromous and at their ascent are all mature or almost so, and all of the same age (one year by otoliths). After spawning begins there is progressive discoloration and emaciation, followed almost invariably by death. About 0.001 per cent. of the stock consists of two-year fish. The eggs are large compared with the size of fish (extremes of standard length in the adult stock are 33 and 70 mm.) and the incubation period is about three weeks. The larvae drift downstream to the sea. Sex ratio is highly variable, but generally the males greatly outnumber the females. A northern and a southern population can be distinguished, the differences being in growth rate and pigmentation. Each population supports a separate fishery, which operates on the ascending shoals. The history of the fisheries is outlined. The southern fishery has never been important because the fish available at the principal fishing locality are excessively pigmented. More suitable fish could be taken by operating further downstream, where the fish are typically at an earlier stage of maturity. The northern fishery has been vigorously prosecuted and overfishing was probably the cause of the decline in abundance of stock in 1947 and 1948. If there was overfishing, it operated purely by excessive removal of reproducers. The order of the optimum catch is empirically identified and a programme for the management of the stock, aiming at its rehabilitation, is recommended.

Population studies and biological control of Pseudaulacaspis pentagona (Targioni-Tozzetti) (Hemiptera: Diaspididae) on passion fruit in Western Samoa

1989 ◽  
Vol 79 (1) ◽  
pp. 163-171 ◽  
Author(s):  
W. J. M. M Liebregts ◽  
D. P. A Sands ◽  
A. S. Bourne
Keyword(s):  
Biological Control ◽  
Microscopic Examination ◽  
Population Studies ◽  
Passion Fruit ◽  
The Other ◽  
Scale Insects ◽  
Adult Females ◽  
Western Samoa ◽  
Pseudaulacaspis Pentagona ◽  
One Year

AbstractThe development of infestations of Pseudaulacaspis pentagona (Targioni-Tozzetti) on passion fruit vines in Western Samoa was monitored at two sites over a period of 20 months, during which the aphelinid parasitoids Encarsia berlesei (Howard) and E. diaspidicola (Silvestri) were released. All vines were rated for P. pentagona infestations, and the female scale insects were counted on selected vines. At one site, the numbers of P. pentagona built up to over 10 000 adult females per vine before the parasitoids became established, and within one year 50% of the vines died. At the other site, where vines survived, an endemic coccinellid predator, Sticholotis quadrisignata Weise, kept populations below 3000 females per vine until the parasitoids became established. Biological control of P. pentagona was achieved at both sites eight months after the parasitoids were introduced. A model for interaction of P. pentagona and parasitoids predicted higher levels for parasitization than revealed by microscopic examination.

scholarly journals Sex Ratio at Birth: Where Did Our Female Fetus Go?

2018 ◽  
Vol 11 (1) ◽  
pp. 1-4
Author(s):  
T K Gurung ◽  
R T Gurung ◽  
R Shrestha ◽  
R Shrestha
Keyword(s):  
Sex Ratio ◽  
Fetal Death ◽  
Sex Ratios ◽  
College Teaching ◽  
Female Gender ◽  
Cross Sectional ◽  
Female Fetus ◽  
Medical College ◽  
Depth Study ◽  
One Year

Objectives: The aim of the study was to determine the ratio of male to female gender at birth and compare the sex ratio between primipara and multipara women.Methods: This is a cross sectional retrospective study done using the data available from the medical records of the patients who were admitted in the labor room of Gandaki Medical College Teaching Hospital from July 2016 to June 2017 (Shrawan 2073 to Asad 2074).Results: In one year period, a total of 1625 women were admitted for delivery. There were 845 male and 780 female babies delivered to those women. The sex ratio calculated was 108 male births for every 100 females. When comparing the sex ratios at birth for primipara, multipara with previous abortions and fetal death and mulipara with no history of abortions and fetal death, the sex ratio was 81.75, 125.89 and 120.16 respectively.Conclusions: Overall there were more male births than female. But in primiparous women more female babies were born unlike in multipara. There is definitely a need of in depth study to identify the cause for the skewed value. The society needs to acknowledge that high sex ratios at birth will adversely affect the fertility patterns causing the imbalance in the overall development of community. J-GMC-N | Volume 11 | Issue 01 | January-June 2018, Page: 1-4  

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