scholarly journals Female Fatality due to Cholera was Higher than Male. Studies of Four Cholera Epidemics in the Poznań Province in the Second Half of the 19th Century.

Author(s):  
GRAŻYNA LICZBIŃSKA ◽  
Miroslav Králík

Abstract Background: Males and females differ in terms of patterns of morbidity and mortality resulting from diseases.Objectives: It has been tested whether cholera epidemics killed selectively by sex in historical populations. Four cholera epidemics in the Poznań Province: 1852, 1855, 1866, and 1873 have been studied.Data sources: Data have been derived from death registers of the selected parishes located on the territory of the Poznań Province. In total, the information about 34, 655 individual cases, with the causes of deaths recognized, has been used, encompassing 18,243 males and 16,325 females. Methods: The daily and weekly incidences of cholera deaths have been counted for epidemics in 1852, 1855, 1866 and 1873. The relations of male-to-female deaths numbers by epidemiological weeks have been computed. The sex ratio at death (SRD) and sex ratio at death from cholera (SRDCh) have been calculated. The differences between the theoretical and empirical distributions in the numbers of male and female deaths, deaths from cholera, SRD and SRDCh have been examined. Results: More females than males died in the periods of cholera epidemics than in non- epidemic ones. The values of SRDCh during the earlier epidemics (1852, 1855) and later epidemics (1866, 1873) were 0.91 and 0.97, respectively. A significant variances in the sex-specific death ratio have been observed between the cholera epidemics periods (SRD=0.89) and non-epidemic periods (SRD=1.13) in Poznań.Conclusions: The gender-specific cholera death rates could have been related to the division of social roles between women and men. Women more frequently than men had contact with contaminated water, e.g. when preparing and cooking meals, feeding, caring for and washing children and caring for sick family members.

2021 ◽  
Author(s):  
Grazyna Liczbinska ◽  
Miroslav Králík

Abstract Males and females differ in terms of patterns of morbidity and mortality resulting from diseases. It has been tested whether cholera epidemics killed selectively by sex in historical populations. Four cholera epidemics in the Poznań Province: 1852, 1855, 1866, and 1873 have been studied. Data have been derived from death registers of the selected parishes located on the territory of the Poznań Province. In total, the information about 34, 655 individual cases, with the causes of deaths recognized, has been used, encompassing 18,243 males and 16,325 females. More females than males died in the periods of cholera epidemics than in non- epidemic ones. The values of sex ratio at death from cholera (SRDCh) during the earlier epidemics (1852, 1855) and later epidemics (1866, 1873) were 0.91 and 0.97, respectively. A significant variances in the sex ratio at death (SRD) have been observed between the cholera epidemics periods (SRD=0.89) and non-epidemic periods (SRD=1.13) in Poznań. The gender-specific cholera death rates could have been related to the division of social roles between women and men. Women more frequently than men had contact with contaminated water, e.g. when preparing and cooking meals, feeding, caring for and washing children and caring for sick family members.


1993 ◽  
Vol 71 (7) ◽  
pp. 1367-1371 ◽  
Author(s):  
Petr E. Komers ◽  
François Messier ◽  
Cormack C. Gates

Sexual segregation in ungulates has been documented for many species including bison. However, male and female bison do not differ in their pattern of habitat selection. In the present study we observed that a fraction of bison groups did not have young (<2 years) despite the presence of males and females. The male to female ratio in these groups was 2.4. We call them adult groups, in contrast to mixed groups, where young were present and the male to female ratio was 0.4. The proportion of cows with young (mothers) in a group was negatively correlated with the male to female ratio, suggesting that mothers associated more often with other cows than with bulls. Before the rut, cows without young (non-mothers) spent less time feeding than either mothers or bulls. However, mothers and non-mothers did not differ in the number of steps per minute they took while grazing, and both types of cows stepped faster than bulls. We suggest that cows feed more selectively than bulls and that the differing foraging strategies result in temporal but not spatial segregation of the sexes. Possibly as a result of similar nutritional demands, mothers tended to aggregate, forming nursery groups. We suggest that the formation of nursery groups can also serve to protect calves through a dilution effect of predation. Whether mothers actually prefer to associate with other mothers remains to be investigated.


2011 ◽  
Vol 15 (6) ◽  
pp. 507-530 ◽  
Author(s):  
Laura Hynes

Abstract This study uses baptismal records from the Italian city of Parma from 1609 to 1637 to chart the sex ratio of male and female infants at baptism. This article measures the Parman sex ratio against the natural sex ratio at birth for live-born infants, as determined by Praven Visaria, and offers preliminary findings that indicate that married couples used infanticide as a means of controlling family size and sex in seventeenth-century Parma. The 28 years studied encompass both relatively strong economic and agricultural years as well as a variety of crises. By selecting a period with both good and bad economic years it is possible to see if parents behaved differently as their household conditions varied. Further, dividing the approximately 30,000 baptisms by rural and urban jurisdictions and familial socio-economic status makes visible parental recourse to infanticide through unnatural ratios of males and females within different segments of society.


2021 ◽  
Author(s):  
Manas Geeta Arun ◽  
Tejinder Singh Chechi ◽  
Rakesh Meena ◽  
Shradha Dattaraya Bhosle ◽  
Srishti ◽  
...  

Divergence in the evolutionary interests of males and females leads to sexual conflict. Traditionally, sexual conflict has been classified into two types: inter-locus sexual conflict (IeSC) and intra-locus sexual conflict (IaSC). IeSC is modeled as a conflict over outcomes of intersexual reproductive interactions mediated by loci that are sex-limited in their effects. IaSC is thought to be a product of selection acting in opposite directions in males and females on traits with a common underlying genetic basis. While in their canonical formalisms IaSC and IeSC are mutually exclusive, there is growing support for the idea that the two may interact. Empirical evidence for such interactions, however, is limited. Here, we investigated the interaction between IeSC and IaSC in Drosophila melanogaster. Using hemiclonal analysis, we sampled 39 hemigenomes from a laboratory-adapted population of D. melanogaster. We measured the contribution of each hemigenome to adult male and female fitness at three different intensities of IeSC, obtained by varying the operational sex-ratio. Subsequently, we estimated the intensity of IaSC at each sex-ratio by calculating the intersexual genetic correlation for fitness and the proportion of sexually antagonistic fitness-variation. Our results indicate a statistically non-significant trend suggesting that increasing the strength of IeSC ameliorates IaSC in the population.


1959 ◽  
Vol 36 (1) ◽  
pp. 34-39
Author(s):  
JAN Z. WILCZYNSKI

1. The percentages of males and females in naturally occurring chains of Crepidula fornicata L. were found to be 39% females, 6% ‘transients’ and 55% males. 2. Disconnected males kept in cages in sea water for 9 months re-established the normal sex ratio. 3. Disconnected males were kept for periods of 4-6 weeks at temperatures of 30° and 10° C. No significant tendency to change sex was observed. 4. Males were injected with extracts of females. No tendency to change sex was observed. 5. In animals of all sizes from small males to large females both male and female gametes are invariably present together. The gametes of both sexes are polymorphic.


Anaconda ◽  
2020 ◽  
pp. 49-78
Author(s):  
Jesús A. Rivas

This chapter examines the lives and tribulations of anacondas. Anacondas, like humans, produce the same number of males and females because the sex ratio is determined by sexual chromosomes. If the sexes start out equally abundant, why would there be so many more males out there in the wild? In some vertebrates one sex or the other disperses away from the area they were born. However, the author does not believe migration plays a significant role with anacondas. For starters, males are the sex with the wanderlust, not females. As such, this would not account for the lower number of females. Moreover, migration should not be very high due to the fact that the study site is the only region that holds water, so animals might move out in the wet season, but they would likely come back in the dry season, when the author did most of the sampling. If migration is not the answer for the uneven sex ratio, one is left with mortality of females as the only explanation. If females suffered higher death rates, that could explain the male bias in the population that the model estimated. Looking further into the results of the population model, the author found that females have a lower estimated survival than males. The chapter then considers the reasons females have higher mortality. The large expenditure in reproduction females incur might result in death not only as a result of predation but also during or after feeding due to weakening.


2003 ◽  
Vol 82 (2) ◽  
pp. 107-116 ◽  
Author(s):  
S. PARNES ◽  
I. KHALAILA ◽  
G. HULATA ◽  
A. SAGI

In the Australian red-claw crayfish Cherax quadricarinatus (von Martens) (Decapoda, Parastacidae), a gonochoristic species, seven different combinations of intersex individuals (with both male and female genital openings) have been described. However, to date, the genetic basis for this phenomenon has not been investigated. This study was designed to test a simple chromosome-based sex-determination model for C. quadricarinatus that assumes the male to be the homogametic (ZZ) sex. According to our model, intersex individuals that are functionally males are genetically females (WZ). Individual crosses were performed between intersex and female crayfish, with control crosses being performed between normal males and females. The control crosses yielded, in most cases, the expected 1[ratio ]1 sex ratio in the F1 progeny. Crosses between intersex individuals and females yielded a 1[ratio ]3 (male[ratio ]female) sex ratio in most crosses. According to our hypothesis, one-third of the females produced in a cross of a female with an intersex animal should be WW females. The hypothesis was tested by crossing normal males with F1 females, which were progeny of intersex fathers. These crosses yielded almost 100% females, a finding that conforms to the above-suggested sex determination model for C. quadricarinatus and the female WZ genotype of intersex individuals.


2017 ◽  
Vol 11 (4) ◽  
pp. 307 ◽  
Author(s):  
Sularto Sularto ◽  
Rita Febrianti ◽  
Suharyanto Suharyanto

Ikan gurami (Osphronemus goramy Lac.) pada ukuran dewasa memiliki bentuk morfometrik yang khas khususnya pada ikan jantan, sehingga dapat dibedakan antara ikan jantan dan betina. Ikan gurami jantan memiliki dahi menonjol dan bibir tebal. Penelitian ini bertujuan untuk mengevaluasi rasio kelamin dan perbedaan performa pertumbuhan antara jantan dan betina. Ikan uji yang digunakan adalah empat populasi ikan gurami yang berbeda yaitu: Kalimantan Selatan, Jambi, Majalengka, dan Tasikmalaya. Penelitian dilaksanakan di Balai Penelitian Pemuliaan Ikan (BPPI), Sukamandi pada bulan Juni 2014 sampai dengan bulan Juli 2015. Hewan uji yang digunakan adalah benih ikan gurami keturunan galur murni berasal dari Kalimantan Selatan, Jambi (strain Batanghari), Majalengka, dan Tasikmalaya. Perawatan telur, pemeliharaan benih, dan pembesaran menggunakan prosedur operasional standar BPPI tentang pemeliharaan ikan gurami. Pemeliharaan ikan gurami dilakukan selama 14 bulan. Hasil penelitian menunjukkan bahwa berdasarkan jenis kelaminnya jumlah ikan gurami betina (67,3%-80,7%) lebih banyak dibandingkan dengan jumlah jantannya (19,3%-32,7%). Setelah mencapai ukuran > 300 g terdapat perbedaan pertumbuhan antara ikan jantan dan betina (P<0,05) yakni jantan tumbuh lebih cepat dibandingkan betina pada semua populasi yakni berkisar antara 4,74%-5,67% untuk karakter panjang standar, dan 14,10%-16,52% untuk karakter bobot. Hal tersebut menunjukkan bahwa ikan gurami memiliki dimorfisme pertumbuhan. Oleh karena itu, ketika dilakukan seleksi berdasarkan pertumbuhan 10% terbaik didapatkan ikan jantan 55%-80% lebih banyak dibandingkan ikan betina (20%-45%).Adult size of giant gouramy (Osphronemus goramy, Lac.) has a distinctive shape of morphometric particularly in male fish, making it easy to distinguish between male and female fishes. Giant gouramy males have a prominent forehead and thick lips. This study aimed to determine sex ratios and differences in growth performance between males and females. This study used 4 progenies of giant gouramy seed from four different populations, namely: Kalimantan, Jambi, Majalengka, and Tasikmalaya, aged 14 months. Eggs incubations,seed maintenance and grow-out were conducted using Standard Operational Procedures of Research Institute for Fish Breeding (RIFB) about the rearing of giant gouramy. Seed rearing were carried out for 14 months. The results showed that, based upon the sex ratio, the number of female was more than the number of males, contituting females 67.3%–80.7% and males from 19.3% to 32.7% of populations. After reaching the size of > 300 g there were a significant difference in growth between males and females (P <0.05), in which males grew faster than females in all populations between 4.74%–5.67% for the standard length and 14.10%–16.52% for the weight characters. IThis result indicated that giant gouramy have growth dimorphism.Therefore, when the selection conducted based on the best growth of top 10%, it was found that the number of male composing 55%–80% was higher than the number of female which only accounted for 20%–45%.


2021 ◽  
Vol 21 (3) ◽  
pp. 235-251
Author(s):  
Mohamad Ayip Firmansyah ◽  
Mustahal Mustahal ◽  
Mas Bayu Syamsunarno ◽  
Muh Herjayanto

Oryzias woworae has a beautiful color and has been traded as ornamental fish. This species is an endemic ricefish from Muna Island, Southeast Sulawesi, and is threatened with endangered status. Information on the optimal spawning sex ratio in O. woworae is unknown. This study aimed was to examine the optimization of reproduction based on the sex ratio of male: female broodstock O. woworae involved in spawning. The sex ratio of male: female spawning broodstock used were 1:1, 1:2, 1:3, and 1:4. The male and female brooders used had a total length of 3,1 ± 0,5 cm and 2,5 ± 0,5 cm. After adaptation, the broodstock of O. woworae was put into aquariums according to the treatment, and each container contained three spawning substrates. The harvesting of eggs on the substrate is carried out two times a day. The results showed that spawning O. woworae with a ratio of 1♂: 4♀ produced the lowest number of eggs and was significantly different with ratios of 1♂: 1♀ and 1♂: 2♀ (P<0,05). The ratio of 1♂ : 3♀ gave the highest egg hatching of 55% but was not significantly different from other treatments (P>0,05). The difference in male and female ratios did not affect the survival rate of O. woworae larvae (P>0,05), with values from 91,9-100%. The highest larvae produced was found in the spawning ratio of 1♂ : 3♀ with 37 larvae but not significantly different from other treatments (P>0,05). The water quality values during the study were temperature 26,5-310C, pH 5,5-8,8, and dissolved oxygen 5,3-6,0 mg L-1. O. woworae broodstock spawning can be optimized with a male to female ratio of 1:3.


2017 ◽  
Vol 9 (1) ◽  
pp. 43
Author(s):  
Nidya Kartini ◽  
Mennofatria Boer ◽  
Ridwan Affandi

Ikan lemuru (Amblygaster sirm) merupakan salah satu komiditas utama di Selat Sunda yang menjadi target nelayan di Pelabuhan Perikanan Pantai Lebuan. Informasi biologi dibutuhkan untuk menyusun langkah konservasi ikan lemuru. Penelitian ini bertujuan untuk menganalisis kondisi biologis ikan lemuru di perairan Selat Sunda melalui pengkajian parameter pertumbuhan, faktor kondisi, dan beberapa aspek reproduksi. Pengambilan ikan contoh dilakukan pada bulan April-Agustus 2015 dari hasil tangkapan nelayan yang didaratkan di PPP Labuan, Banten menggunakan teknik Penarikan Contoh Acak Berlapis. Jumlah ikan contoh yang diambil selama penelitian sebanyak 527 ekor ikan jantan dan 245 ekor ikan betina. Hasil penelitian menunjukkan bahwa pola pertumbuhan ikan lemuru jantan dan betina adalah isometrik, nilai faktor kondisi ikan lemuru jantan berkisar 0,9346 – 1,0294 dan betina berkisar 0,9401 – 1,0738, parameter pertumbuhan L∞, K, dan t0 pada ikan jantan adalah 248,80 mm; 0,24/tahun;dan -0,38. Adapun parameter (L∞, K, dan t0) pada ikan betina adalah 235,26 mm; 0,46/tahun, dan -0,20. Nisbah kelamin ikan lemuru jantan dan betina TKG IV adalah 0,75:1. Ukuran pertama kali matang gonad (Lm) ikan lemuru jantan dan betina adalah 188 mm dan 186 mm. Sedangkan ukuran pertama kali tertangkap (Lc) ikan lemuru jantan dan betina adalah 172 mm dan 173 mm. Musim pemijahan ikan lemuru diduga terjadi pada bulan Mei dan Juli.The spotted sardinella (Amblygaster sirm) was one of main commodities in the Sunda Strait that maily targeted by fishers in Labuan Coastal Fishing Port, Banten. The biological  information  needed to setup conservation measure of the spotted sardinella. This research aims to analyse the biological conditions of spotted sardinella in the Sunda Strait by reviewing parameters of growth, condition factor, and some reproduction aspect. Research was conducted in April-August 2015 in Labuan Coastal Fishing Port, Banten by using Random Stratified Sampling technique. About 700 samples (527 male and 245 female fishes) collected during study. The results showed that the growth pattern of male and female were isometric, value of condition factor for male ranged from 0,9346 – 1,0294 and for female ranged from 0,9401 – 1,0738. The estimated growth parameters (L∞, K, and t0) for male were 248,80 mm; 0,24 year-1;and -0,38 respectively. While, the parameters (L∞, K, and t0) of female were 235,26 mm; 0,46 year-1;and -0,20 respectively. The sex ratio between males and females for spotted sardinella was 0,75:1. The size at first maturity (Lm) of male and female were 188 mm and 186 mm, respectively. In addition, the size a first caught (Lc) of male and female was 172 mm and 173 mm, respectively. Thespawning season spotted sardinella possibly occurs in May and July.


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