Early and late fawn mortality in a remnant population of Arabian gazelles (Gazella arabica)

AbstractThe Arabian gazelle (Gazella arabica) population in Israel has experienced a turbulent conservation history and repeatedly faced local extinction. Low fawn survival was considered the main cause for the constant decline. In our study, we analyzed instantaneous fawn mortality rates, using a binomial coding at three different developmental stages, i.e., mortality rates to 3 months after parturition (weaning age), to 5 months after parturition (male fawns leave their mothers), and to the age of reproductive maturity, i.e., recruitment (12 months). We used a dataset obtained from 20 individually discernible mothers and their fawns (49 females and 48 males) born between June 2006 and September 2019. To explore causes for the fawn mortality rates, parental- (age of the mother at parturition) and offspring-related attributes (offspring sex), year of birth, together with one weather variable (mean monthly maximum temperature) were included as independent variables into three independent mixed effects cox regression models. Out of 97 fawns, 92 survived to weaning age, 73 to the age of 5 months and only 7 to the age of reproductive maturity. Temperature had significant effects on instantaneous fawn mortality rates, suggesting that low temperatures were detrimental to the survival of fawns after weaning (4–5 months) and male dispersal age (6–12 months). Male offspring encountered a higher instantaneous mortality rate than female offspring at the age of 6–12 months. Moreover, fawns from less experienced mother (young age at parturition) experienced higher mortality. Our results were in line with previous studies on fawn mortality observed in other desert dwelling ungulates.

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Adjustment of fecundity and sex ratio in response to social environments in a haplodiploid mite

Systematic and Applied Acarology ◽

10.11158/saa.27.1.7 ◽

2022 ◽

Author(s):

Nuwan Weerawansha ◽

Qiao Wang ◽

Xiong Zhao He

Keyword(s):

Population Density ◽

Sex Ratio ◽

Population Size ◽

Local Population ◽

Female Offspring ◽

Social Environments ◽

Positive Interaction ◽

Offspring Sex Ratio ◽

Offspring Sex ◽

Large Populations

Animals can adjust reproductive strategies in favour of corporation or competition in response to local population size and density, the two key factors of social environments. However, previous studies usually focus on either population size or density but ignore their interactions. Using a haplodiploid spider mite, Tetranychus ludeni Zacher, we carried out a factorial experiment in the laboratory to examine how ovipositing females adjust their fecundity and offspring sex ratio during their early reproductive life under various population size and density. We reveal that females laid significantly more eggs with increasing population size and significantly fewer eggs with increasing population density. This suggests that large populations favour cooperation between individuals and dense populations increase competition. We demonstrate a significant negative interaction of population size and density that resulted in significantly fewer eggs laid in the large and dense populations. Furthermore, we show that females significantly skewed the offspring sex ratio towards female-biased in small populations to reduce the local mate competition among their sons. However, population density incurred no significant impact on offspring sex ratio, while the significant positive interaction of population size and density significantly increased the proportion of female offspring in the large and dense populations, which will minimise food or space competition as females usually disperse after mating at crowded conditions. These results also suggest that population density affecting sex allocation in T. ludeni is intercorrelated with population size. This study provides evidence that animals can manipulate their reproductive output and adjust offspring sex ratio in response to various social environments, and the interactions of different socio-environmental factors may play significant roles.

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Association of Preceding Antithrombotic Therapy in Atrial Fibrillation Patients With Ischemic Stroke, Intracranial Hemorrhage, or Gastrointestinal Bleed and Mortality

European Heart Journal - Cardiovascular Pharmacotherapy ◽

10.1093/ehjcvp/pvz063 ◽

2019 ◽

Cited By ~ 3

Author(s):

Joris J Komen ◽

Tomas Forslund ◽

Aukje K Mantel-Teeuwisse ◽

Olaf H Klungel ◽

Mia von Euler ◽

...

Keyword(s):

Atrial Fibrillation ◽

Ischemic Stroke ◽

Propensity Score ◽

Intracranial Hemorrhage ◽

Cox Regression ◽

Mortality Rates ◽

Antithrombotic Treatment ◽

Healthcare Database ◽

Gastrointestinal Bleed ◽

History Of

Abstract Aims To analyze 90-day mortality in AF patients after a stroke or a severe bleed and assess associations with the type of antithrombotic treatment at the event. Methods and Results From the Stockholm Healthcare database, we selected 6 017 patients with a known history of AF who were diagnosed with ischemic stroke, 3 006 with intracranial hemorrhage, and 4 291 with a severe gastrointestinal bleed (GIB). The 90-day mortality rates were 25.1% after ischemic stroke, 31.6% after intracranial hemorrhage, and 16.2% after severe GIB. We used Cox regression and propensity score matched analyses to test the association between antithrombotic treatment at the event and 90-day mortality. After intracranial hemorrhage, there was a significantly higher mortality rate in warfarin compared to NOAC treated patients (adjusted hazard ratio (aHR): 1.36 CI: 1.04 – 1.78). After an ischemic stroke and a severe GIB, patients receiving antiplatelets or no antithrombotic treatment had significantly higher mortality rates compared to patients on NOACs, but there was no difference comparing warfarin to NOACs (aHR 0.84 CI: 0.63 – 1.12 after ischemic stroke, aHR 0.91 CI: 0.66 – 1.25 after severe GIB). Propensity score matched analysis yielded similar results. Conclusion Mortality rates were high in AF patients suffering from an ischemic stroke, an intracranial hemorrhage, or a severe GIB. NOAC treatment was associated with a lower 90 day mortality after intracranial hemorrhage than warfarin.

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Reproduction and Offspring Sex Ratios Differ Markedly among Closely Related Hyperparasitoids Living in the Same Microhabitats

Journal of Insect Behavior ◽

10.1007/s10905-019-09730-z ◽

2019 ◽

Vol 32 (3) ◽

pp. 243-251 ◽

Cited By ~ 1

Author(s):

Jeffrey A. Harvey ◽

Lucas de Haan ◽

Oriol Verdeny-Vilalta ◽

Bertanne Visser ◽

Rieta Gols

Keyword(s):

Reproductive Success ◽

Sex Ratios ◽

Reproductive Traits ◽

Female Offspring ◽

Forest Edge ◽

Cotesia Glomerata ◽

Small Scale ◽

Lifetime Reproductive Success ◽

Closely Related Species ◽

Offspring Sex

Abstract Closely related species in nature usually exhibit very similar phylogenetically conserved traits, such as reproduction, behavior and development. Here, we compared fecundity schedules, lifetime reproductive success and offspring sex ratios in three congeneric facultative hyperparasitoid wasps that exhibit several overlapping traits and which co-occur in the same small-scale habitats. Gelis agilis, G. proximus and G. hortensis are abundant in meadows and forest edge habitats in the Netherlands. Gelis agilis is asexual (all female), whereas the other two species reproduce sexually. Here they developed on cocoons of the primary parasitoid Cotesia glomerata. When provided with unlimited hosts, lifetime reproductive success was three times higher in G. proximus than in G. agilis with G. hortensis producing intermediate numbers of offspring. All three species depleted their teneral reserves during their lives. Females of G. proximus and G. hortensis lived significantly longer than females of G. agilis. Offspring sex ratios in young G. proximus mothers were female-biased and marginally male-biased in G. hortensis. As mothers aged, however, the ratio of male:female progeny produced rapidly increased until no daughters emerged later in life. Our results reveal significant differences in reproductive traits among the three species despite them co-occurring in the same microhabitats, being very closely related and morphologically similar. The increase in the production of male progeny by Gelis mothers over time suggests a depletion in sperm number or viability with age. This is especially interesting, given that Gelis species are among the least fecund parasitoids thus far studied. It is likely that in the field most Gelis mothers are probably only able to parasitize a few hosts and to maintain the production of female offspring.

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Sperm sex ratio adjustment in a mammal: perceived male competition leads to elevated proportions of female-producing sperm

Biology Letters ◽

10.1098/rsbl.2019.0929 ◽

2020 ◽

Vol 16 (6) ◽

pp. 20190929

Author(s):

Renée C. Firman ◽

Jamie N. Tedeschi ◽

Francisco Garcia-Gonzalez

Keyword(s):

Sex Ratio ◽

Sex Allocation ◽

Sex Ratios ◽

Female Offspring ◽

Male Competition ◽

Offspring Sex ◽

Sex Ratio Adjustment ◽

Adaptive Adjustment ◽

Male House

Mammal sex allocation research has focused almost exclusively on maternal traits, but it is now apparent that fathers can also influence offspring sex ratios. Parents that produce female offspring under conditions of intense male–male competition can benefit with greater assurance of maximized grand-parentage. Adaptive adjustment in the sperm sex ratio, for example with an increase in the production of X-chromosome bearing sperm (CBS), is one potential paternal mechanism for achieving female-biased sex ratios. Here, we tested this mechanistic hypothesis by varying the risk of male–male competition that male house mice perceived during development, and quantifying sperm sex ratios at sexual maturity. Our analyses revealed that males exposed to a competitive ‘risk’ produced lower proportions of Y-CBS compared to males that matured under ‘no risk’ of competition. We also explored whether testosterone production was linked to sperm sex ratio variation, but found no evidence to support this. We discuss our findings in relation to the adaptive value of sperm sex ratio adjustments and the role of steroid hormones in socially induced sex allocation.

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A note on the effect of weaning age on lamb production

Animal Science ◽

10.1017/s0003356100028610 ◽

1969 ◽

Vol 11 (4) ◽

pp. 569-572

Author(s):

M. A. Sharafeldin ◽

I. A. Ramadan

Keyword(s):

Mortality Rates ◽

The Body ◽

The Other ◽

Suckling Period ◽

Group Iii ◽

Group I ◽

Body Weights ◽

Weaning Age ◽

Group Ii ◽

Better Than

SUMMARYAt birth, the Barki lambs used in this experiment were randomly allocated to three groups which numbered 133, 126 and 154 lambs of both sexes weaned at the ages of 10 weeks (Group I), 12 weeks (Group II) and 16 weeks (Group III) respectively.The most pronounced differences between the three groups of lambs in their body weights took place at the age from 4 to 6 months. Group II lambs performed as well as or even slightly better than the other two groups, which leads to the conclusion that as far as the body weight of lambs is concerned there is no need to extend their suckling period more than 12 weeks.The three groups of lambs varied little in their mortality rates from 2·5 to 12 months of age.

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Vitamin D and Mortality: A Mendelian Randomization Study

Clinical Chemistry ◽

10.1373/clinchem.2012.193185 ◽

2013 ◽

Vol 59 (5) ◽

pp. 793-797 ◽

Cited By ~ 28

Author(s):

Olivia Trummer ◽

Stefan Pilz ◽

Michael M Hoffmann ◽

Bernhard R Winkelmann ◽

Bernhard O Boehm ◽

...

Keyword(s):

Vitamin D ◽

Mendelian Randomization ◽

Cox Regression ◽

Mortality Rates ◽

Coefficient Of Determination ◽

Nucleotide Polymorphisms ◽

Reductase Gene ◽

25 Hydroxy Vitamin D ◽

25 Oh Vitamin D

BACKGROUND Decreased circulating 25-hydroxy-vitamin D (25-OH-vitamin D) concentrations have been associated with mortality rates, but it is unclear whether this association is causal. We performed a Mendelian randomization study and analyzed whether 3 common single-nucleotide polymorphisms (SNPs) associated with 25-OH-vitamin D concentrations are causal for mortality rates. METHODS Genotypes of SNPs in the group-specific component gene (GC, rs2282679), 7-dehydrocholesterol reductase gene (DHCR7, rs12785878), and cytochrome P450 IIR-1 gene (CYP2R1, rs10741657) were determined in a prospective cohort study of 3316 male and female participants [mean age 62.6 (10.6) years] scheduled for coronary angiography between 1997 and 2000. 25-OH-vitamin D concentrations were determined by RIA. The main outcome measures were all-cause deaths, cardiovascular deaths, and noncardiovascular deaths. RESULTS In a linear regression model adjusting for month of blood sampling, age, and sex, vitamin D concentrations were predicted by GC genotype (P < 0.001), CYP2R1 genotype (P = 0.068), and DHCR7 genotype (P < 0.001), with a coefficient of determination (r2) of 0.175. During a median follow-up time of 9.9 years, 955 persons (30.0%) died, including 619 deaths from cardiovascular causes. In a multivariate Cox regression adjusted for classical risk factors, GC, CYP2R1, and DHCR7 genotypes were not associated with all-cause mortality, cardiovascular mortality, or noncardiovascular mortality. CONCLUSIONS Genetic variants associated with 25-OH-vitamin D concentrations do not predict mortality. This suggests that low 25-OH-vitamin D concentrations are associated with, but unlikely to be causal for, higher mortality rates.

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Genetic evidence for co-occurrence of chromosomal and thermal sex-determining systems in a lizard

Biology Letters ◽

10.1098/rsbl.2007.0583 ◽

2007 ◽

Vol 4 (2) ◽

pp. 176-178 ◽

Cited By ~ 96

Author(s):

Rajkumar S Radder ◽

Alexander E Quinn ◽

Arthur Georges ◽

Stephen D Sarre ◽

Richard Shine

Keyword(s):

Sex Determination ◽

Female Offspring ◽

Temperature Dependent ◽

Sex Marker ◽

Heteromorphic Sex Chromosomes ◽

Offspring Sex ◽

Current Classification ◽

Genotypic Sex Determination ◽

Incubation Temperatures ◽

Bassiana Duperreyi

An individual's sex depends upon its genes (genotypic sex determination or GSD) in birds and mammals, but reptiles are more complex: some species have GSD whereas in others, nest temperatures determine offspring sex (temperature-dependent sex determination). Previous studies suggested that montane scincid lizards ( Bassiana duperreyi , Scincidae) possess both of these systems simultaneously: offspring sex is determined by heteromorphic sex chromosomes (XX–XY system) in most natural nests, but sex ratio shifts suggest that temperatures override chromosomal sex in cool nests to generate phenotypically male offspring even from XX eggs. We now provide direct evidence that incubation temperatures can sex-reverse genotypically female offspring, using a DNA sex marker. Application of exogenous hormone to eggs also can sex-reverse offspring (oestradiol application produces XY as well as XX females). In conjunction with recent work on a distantly related lizard taxon, our study challenges the notion of a fundamental dichotomy between genetic and thermally determined sex determination, and hence the validity of current classification schemes for sex-determining systems in reptiles.

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The use of a heated nestbox system to counter perinatal mortality in the commercial rabbit

Animal Science ◽

10.1017/s0003356100001628 ◽

1983 ◽

Vol 37 (1) ◽

pp. 125-132 ◽

Cited By ~ 1

Author(s):

G. G. Partridge ◽

J. M. Bruce ◽

S. J. Allan ◽

G. A. M. Sharman

Keyword(s):

Surface Temperature ◽

Ambient Temperature ◽

Strong Influence ◽

Post Partum ◽

Mortality Rates ◽

Cold Winter ◽

Heated Floor ◽

Weaning Age ◽

Preliminary Study ◽

Reproductive Cycles

ABSTRACTA rabbit nesting box incorporating a low wattage heated floor was developed. In a preliminary study a floor surface temperature in the box of 27°C was found to be adequate to minimize chilling of young pups in the nest. A full scale trial followed using 44 crossbred does, 22 provided with a nestbox containing a heated floor and 22 with a control plywood nesting box. The experiment continued for six successive reproductive cycles over the period April 1981 to February 1982 in an unheated rabbitry. Throughout the year significantly more pups reached weaning age when does were provided with nestboxes containing heated floors. On average, 0·15 of all pups born to does with heated floors had died by 28 days post partum, the comparable figure for unheated floors being 0·56. This reduction in mortality in heated boxes was apparent both on the day of birth and in the subsequent weeks prior to weaning. Ambient temperature and the wetness of the nest had a strong influence on the survival of pups in control boxes with high mortality rates experienced in the cold winter months (0·79 in February 1982). Most of these deaths in the control boxes were attributable to chilling and/or starvation in the nest (0·53 of diagnosed deaths overall). The running costs of the heated nestbox system are discussed.

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Cohort Study of the Impact of Time to Antibiotic Administration on Mortality in Patients with Febrile Neutropenia

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.02561-14 ◽

2014 ◽

Vol 58 (7) ◽

pp. 3799-3803 ◽

Cited By ~ 64

Author(s):

Regis G. Rosa ◽

Luciano Z. Goldani

Keyword(s):

Cohort Study ◽

Febrile Neutropenia ◽

Cancer Patients ◽

Cox Regression ◽

Mortality Rates ◽

Cox Proportional Hazards Model ◽

Rank Test ◽

Antibiotic Administration ◽

Cox Regression Analysis ◽

The Impact

ABSTRACTThe time to antibiotic administration (TTA) has been proposed as a quality-of-care measure in febrile neutropenia (FN); however, few data regarding the impact of the TTA on the mortality of adult cancer patients with FN are available. The objective of this study was to determine whether the TTA is a predictor of mortality in adult cancer patients with FN. A prospective cohort study of all consecutive cases of FN, evaluated from October 2009 to August 2011, at a single tertiary referral hospital in southern Brazil was performed. The TTA was assessed as a predictive factor for mortality within 28 days of FN onset using the Cox proportional hazards model. Kaplan-Meier curves were used for an assessment of the mortality rates according to different TTAs; the log-rank test was used for between-group comparisons. In total, 307 cases of FN (169 subjects) were evaluated. During the study period, there were 29 deaths. In a Cox regression analysis, the TTA was independently associated with mortality within 28 days (hazard ratio [HR], 1.18; 95% confidence interval [CI], 1.10 to 1.26); each increase of 1 h in the TTA raised the risk of mortality within 28 days by 18%. Patients with FN episodes with a TTA of ≤30 min had lower 28-day mortality rates than those with a TTA of between 31 min and 60 min (3.0% versus 18.1%; log-rankP= 0.0002). Early antibiotic administration was associated with higher survival rates in the context of FN. Efforts should be made to ensure that FN patients receive effective antibiotic therapy as soon as possible. A target of 30 min to the TTA should be adopted for cancer patients with FN.

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Risk factors associated with suicide among esophageal carcinoma patients from 1975 to 2016

Scientific Reports ◽

10.1038/s41598-021-98260-w ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Chongfa Chen ◽

Huapeng Lin ◽

Fengfeng Xu ◽

Jianyong Liu ◽

Qiucheng Cai ◽

...

Keyword(s):

Risk Factors ◽

Esophageal Cancer ◽

Cancer Patients ◽

Alaska Native ◽

Cox Regression ◽

Mortality Rates ◽

Histologic Grade ◽

Black Race ◽

Suicide Rates ◽

Grade Iii

AbstractThroughout the world, esophageal cancer patients had a greater suicidal risk compared with ordinary people. Thus, we aimed to affirm suicide rates, standardized mortality rates, and underlying suicide-related risk factors of esophageal cancer patients. Patients suffering esophageal cancer were chosen from the Surveillance, Epidemiology, and End Results repository in 1975–2016. Suicide rates as well as standardized mortality rates in the patients were measured. Univariable and multivariable Cox regression had been adopted for establishing the latent suicide risk factors among patients suffering esophageal cancer. On multivariable Cox regression, gender (male vs. female, HR: 6.37), age of diagnosis (70–105 vs. 0–55, HR: 2.69), marital status, race (white race vs. black race, HR: 6.64; American Indian/Alaska Native, Asian/Pacific Islander vs. black race, HR: 8.60), histologic Grade (Grade III vs. Grade I, HR: 2.36), no surgery performed (no/unknown vs. yes, HR: 2.01), no chemotherapy performed were independent risk factors related to suicide in patients suffering esophageal cancer. Male sex, the older age, unmarried state, non-black race, histologic Grade III, no surgery performed, no chemotherapy performed were strongly related to suicide in patients suffering esophageal cancer.

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