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Female Age (female + age)
Selected AbstractsIntrapopulation variation in reproduction by female eastern kingbirds Tyrannus tyrannus: the impacts of age, individual performance, and breeding siteJOURNAL OF AVIAN BIOLOGY, Issue 3 2004Michael T. Murphy I used data from a 13-year study of eastern kingbirds Tyrannus tyrannus from central New York, USA, to evaluate the relative impact of female age and body size on reproduction. I also calculated repeatabilities of reproductive traits for both females and the sites where they bred in an attempt to evaluate the relative contribution of each to intrapopulation variation in reproduction. Female age had a strong influence on timing of breeding (breeding date advanced by one day for each year of life), but was not a significant source of variation for clutch size, egg mass, number of young to hatch or fledge, or total seasonal production. Repeatabilities of breeding date for females and sites were both significant (0.284 and 0.181, respectively), but the only other significant repeatabilities were for female clutch size (0.282) and female egg mass (0.746). Among-year repeatabilities of breeding date for females who bred at two or more sites over their lifetime were as high as those for females that were site faithful. Thus, breeding date was probably affected independently by the female and site. No measure of productivity exhibited a repeatable pattern in comparisons made among females or sites. All reproductive traits were entered as dependent variables in a series of stepwise multiple regression analyses in an attempt to identify female properties (size, lifespan and condition) that might be linked proximately to differences in breeding statistics. I found that (a) large birds tended to breed the earliest, (b) clutch size was independent of female size, condition and lifespan, (c) female body size and egg size were correlated positively, but (d) production of young was independent of all measured female properties. Reproduction appears to be linked more closely to the female than to the site. Body size accounts for a portion of the repeatable portion of breeding date and egg mass, but most of the intrapopulation variation in these and other traits remained unexplained. [source] Influence of motility and vitality in intracytoplasmic sperm injection with ejaculated and testicular spermANDROLOGIA, Issue 4 2005T. Stalf Summary The vitality of spermatozoa used for intracytoplasmic sperm injection (ICSI) is a crucial factor for fertilization, establishment and outcome of a pregnancy in assisted reproductive technique cycles. The sperm origin may also be a limiting factor, although little is known about this issue. It is known that the motility of injected spermatozoa and their origin from ejaculate or testicular biopsies are important predictors in terms of fertilization, pregnancy and birth rates. Oocytes of patients in 2593 cycles were retrieved in our in vitro fertilization programme and inseminated via ICSI. We used motile (group 1, n = 2317) or immotile ejaculated spermatozoa (group 2, n = 79), motile sperm retrieved from testicular biopsies (group 3, n = 62) and immotile spermatozoa from testicular biopsies (group 4, n = 135). Female age and number of oocytes retrieved did not differ significantly among the groups. The fertilization rates were as follows: 67.1% in group 1, 49.8% in group 2, 68.3% in group 3 and 47.8% in group 4. The pregnancy rates in cases where three embryos had been transferred amounted to 35.7% in group 1, 17.3% in group 2, 38.3% in group 3 and 20.5% in group 4. The embryo quality showed no differences between groups 1 and 3 (14.5), and between groups 2 (11.8) and 4 (10.8). The abortion rate was similar in groups 1,3, but increased in group 4 (26.6%, 27.3%, 31.6% and 55.5%). Irrespective of their origin, the fertilization potential of injected spermatozoa was found to be influenced by motility. The resulting pregnancy and birth rates, i.e. the potential of the resulting embryos to implant and to achieve viable pregnancies, seem to be additionally dependent on the sperm origin. This was well shown by declining rates when spermatozoa in a relatively early stage of maturity had been used. We see increasing evidence that the degree of sperm maturity has an important impact on the outcome of ICSI. In obstructive azoospermia, spermatozoa retrieved from the epididymis should be used rather than testicular biopsy spermatozoa, or testicular sperm should be preincubated in culture medium before ICSI. [source] Laboratory-based reproduction success of ruffe, Gymnocephalus cernuus (L.), in brackish water is determined by maternal propertiesECOLOGY OF FRESHWATER FISH, Issue 2 2006A. Albert Abstract,, Body length, age, egg size, embryo salinity tolerance and length at hatching of the freshwater (salinity <0.1 ppt, Lake Peipsi) and brackish-water (salinity 2,6 ppt, Pärnu and Matsalu Bay) ruffe, Gymnocephalus cernuus (L.), were examined to reveal their reproductive success in moderate salinity. Eggs of females originating from brackish water were significantly larger than eggs of freshwater females. No correlation between egg size and female size and age was found in brackish-water populations. In the freshwater population there was a small negative correlation between egg size and female size, but no correlation with female age. Fertilisation by sperm of males of different origin (brackish water or freshwater) produced no significant differences at any critical developmental stage (fertilisation, gastrulation, hatching) in the development of eggs from brackish-water or freshwater females at 3.3, 5.5, 7.7 and 9.9 ppt salinity. Survival rates in different salinity depended only on female origin; embryonic salinity tolerance was higher in ruffe inhabiting brackish water. Obviously, embryo salinity tolerance in ruffe is determined by egg qualities. [source] AGE-SPECIFIC GENETIC AND MATERNAL EFFECTS IN FECUNDITY OF PREINDUSTRIAL FINNISH WOMENEVOLUTION, Issue 9 2008Jenni E. Pettay A population's potential for evolutionary change depends on the amount of genetic variability expressed in traits under selection. Studies attempting to measure this variability typically do so over the life span of individuals, but theory suggests that the amount of additive genetic variance can change during the course of individuals' lives. Here we use pedigree data from historical Finns and a quantitative genetic framework to investigate how female fecundity, throughout an individual's reproductive life, is influenced by "maternal" versus additive genetic effects. We show that although maternal effects explain variation in female fecundity early in life, these effects wane with female age. Moreover, this decline in maternal effects is associated with a concomitant increase in additive genetic variance with age. Our results thus highlight that single over-lifetime estimates of trait heritability may give a misleading view of a trait's potential to respond to changing selection pressures. [source] Age-dependent reproductive performance in Northern Goshawks Accipiter gentilisIBIS, Issue 1 2003Jan Tøttrup Nielsen The age-specific reproductive performance of Northern Goshawks Accipiter gentilis was studied over 22 years in Denmark. The age of the breeding female in relation to the number of young raised was known in 929 breeding attempts, while the age of both the male and the female was known in 496 breeding attempts. The number of fledglings raised per breeding attempt increased with both male and female age, but only for females was it possible to conduct a detailed analysis of this age-dependent relationship. The annual production of fledglings increased with female age from 1 to 7 years of age, whereupon it started to decline. A longitudinal analysis showed that this mean population trend could be attributed to similar age-related trends in individual females. Previous breeding experience did not influence the number of fledglings produced by individual females, and poorly performing females apparently survived with the same probability as well performing ones. The most likely explanation for the age-dependent reproductive performance in the observed Goshawk population appeared to be age-related improvements in competence, such as foraging efficiency. [source] Comparison of the outcome of intracytoplasmic sperm injection in obstructive and non-obstructive azoospermia in the first cycle: a report of case series and meta-analysisINTERNATIONAL JOURNAL OF ANDROLOGY, Issue 1 2005MOHAMED GHANEM Summary To investigate the outcome of intracytoplasmic sperm injection with fresh and cryopreserved-thawed testicular spermatozoa in the first cycle in patients with obstructive azoospermia (OA) and non-obstructive azoospermia (NOA), a total of 90 cases, 48 OA and 42 NOA were studied. All patients underwent sperm retrieval by testicular sperm extraction (TESE) while their wives received conventional ovarian hyperstimulation. The hormone levels, testicular histology, the rates of sperm retrieval, fertilization, implantation and pregnancy were analysed and evaluated. This study and other four similar studies were subjected to meta-analysis. Sperm retrieval was successful in 100% OA and 61% NOA. Fresh spermatozoa were used in 87.5% and 92.4% of OA and NOA cases respectively; while cryopreserved-thawed spermatozoa were used in 12.5% and 7.6% of OA and NOA, respectively. The fertilization, implantation and clinical pregnancy rates were 65.5%, 15% and 25% respectively in OA group, and 54.2%, 5% and 23.1% respectively in NOA group. Sperm status (fresh or thawed), male partner's age, female age and male serum follicle-stimulating hormone had no significant effect upon fertilization rate, implantation rate, or pregnancy rate per embryo transfer. The results of meta-analysis indicate that there is no statistically significant difference in clinical pregnancy rates between the two groups. There was a significantly higher fertilization rate among OA patients in all analysed studies (95% CI = 14.29,15.71, d.f. 832, T = 1.96). In conclusion, although the fertilization rate was significantly higher in the OA group in our study and from the given meta-analysis, there were some differences as regards pregnancy rates. Although the overall effect was more or less similar pregnancy rates in both subtypes of azoospermia, this may not be true if non-male infertility variables were controlled for in all studies. [source] Age-related change in breeding performance in early life is associated with an increase in competence in the migratory barn swallow Hirundo rusticaJOURNAL OF ANIMAL ECOLOGY, Issue 5 2007JAVIER BALBONTÍN Summary 1We investigated age-related changes in two reproductive traits (laying date and annual fecundity) in barn swallows Hirundo rustica L. using a mixed model approach to di-stinguish among between- and within-individual changes in breeding performance with age. 2We tested predictions of age-related improvements of competence (i.e. constraint hypothesis) and age-related progressive disappearance of poor-quality breeders (i.e. selection hypothesis) to explain age-related increase in breeding performance in early life. 3Reproductive success increased in early life, reaching a plateau at middle age (e.g. at 3 years of age) and decreasing at older age (> 4 years). Age-related changes in breeding success were due mainly to an effect of female age. 4Age of both female and male affected timing of reproduction. Final linear mixed effect models (LME) for laying date included main and quadratic terms for female and male age, suggesting a deterioration in reproductive performance at older age for both males and females. 5We found evidence supporting the constraints hypothesis that increases in competence within individuals, with ageing being the most probable cause of the observed increase in breeding performance with age in early life. Two mechanisms were implicated: (1) advance in male arrival date with age provided middle-aged males with better access to mates. Yearling males arrived later to the breeding grounds and therefore had limited access to high-quality mates. (2) Breeding pairs maintaining bonds for 2 consecutive years (experienced pairs) had higher fecundity than newly formed inexperienced breeding pairs. 6There was no support for the selection hypothesis because breeding performance was not correlated with life span. 7We found a within-individual deterioration in breeding and migratory performance (arrival date) in the oldest age-classes consistent with senescence in these reproductive and migratory traits. [source] Climate predictability and breeding phenology in red deer: timing and synchrony of rutting and calving in Norway and FranceJOURNAL OF ANIMAL ECOLOGY, Issue 4 2005L. E. LOE Summary 1Timing and synchrony of reproduction are regarded as crucially important factors for fitness in seasonal environments. Natural selection has probably favoured temperate and arctic female herbivores that match reproduction with onset of plant growth in spring. However, breeding synchrony may also be affected by variation in phenotypic quality of females in a population, because females in poor body condition have been found to delay ovulation and subsequent calving. 2We compared breeding phenology, i.e. the timing and synchrony of rutting (roaring, sexual aggregation) and calving of red deer (Cervus elaphus L.) in France (latitude: 49°N) and Norway (latitude: 63°N). We hypothesized (H1) that calving and rutting were later at the site with latest onset of plant growth. 3We further quantified overall environmental predictability as the sum of annual constancy and seasonality and tested three different (not mutually exclusive) hypotheses about breeding synchrony: (H2a) the population experiencing most seasonal plant phenology should show the highest breeding synchrony; (H2b) overall predictability of plant phenology should determine breeding synchrony; and (H2c) breeding should be more synchronized in the population with lowest female body weight variation within age classes because they ovulate more synchronously. 4Calving and rutting, as well as onset of plant phenology, were later in Norway than in France, complying with the first hypothesis. Plant growth in spring was overall more predictable and also more seasonal in Norway than France. Hence we expected higher breeding synchrony in Norway than in France according to H2a and H2b. Variance in female body weight was slightly higher in France than in Norway, which should also cause more synchronized breeding in Norway than in France (H2c). Contrary to all predictions, variance in rutting and calving dates was around two times higher in Norway than in France. 5We suggest two alternative explanations of breeding synchrony. A more variable topography in Norway can make optimal birth date more variable on a local scale than in France, thereby maintaining a higher genetic variance for calving date in Norwegian red deer. Further, population age structure may play a role, as ovulation varies according to female age. Clearly, processes of breeding synchrony are far more complex than previously realized. [source] Patterns of reproductive effort and success in birds: path analyses of long-term data from European ducksJOURNAL OF ANIMAL ECOLOGY, Issue 2 2002Peter Blums Summary 1We tested ecological hypotheses about timing of breeding and reproductive effort in birds, by analysing > 15-year data sets for individually marked females in three species of Latvian ducks (northern shoveler, tufted duck, common pochard). 2Duckling survival and recruitment declined with advancing hatch date in pochard and tufted duck, after controlling for effects of female age and other factors with path analysis, a novel finding which indicates that fitness advantages associated with early hatching extended beyond the prefledging period. Logistic regression analysis suggested further that individual duckling prefledging survival was moderate in the earliest phase of the breeding season, greatest in mid-season and lowest later on. 3However, selection acting against early hatched ducklings was surpassed by strong directional selection favouring recruitment of the earliest hatching females. The absolute and relative numbers of female recruits produced by a breeding female declined sharply with advancing hatch date in all species. 4Unlike previous studies, an hypothesized intraspecific trade-off between duckling mass and brood size was detected, being very robust in two of three species. 5Unexpectedly, female age effects on recruitment were manifested only indirectly by several pathways, the most important being the earlier hatching dates of older females. Size-adjusted body mass (i.e. condition index) was positively related to reproductive success, and was 2,8-fold more influential than female size (indexed by wing length). 6Overall, fecundity-independent variables (e.g. hatching date, weather, indices of duckling production and habitat quality) generally had 2,10 times greater influence on recruitment rates than did fecundity-dependent variables such as female size or condition, duckling mass and brood size, suggesting a critical role for external environmental factors vs. individual female-specific traits in the recruitment process. [source] Group breeding dramatically increases reproductive success of yearling but not older female scrubwrens: a model for cooperatively breeding birds?JOURNAL OF ANIMAL ECOLOGY, Issue 3 2001Robert D. Magrath Summary 1,Many studies of cooperatively breeding birds have found no effect of group size on reproductive success, contrary to predictions of most adaptive hypotheses. A model is proposed for variation in group-size effects: group size has a reduced effect on success when conditions for breeding are good, such as in good environmental conditions or in groups with older breeders. This hypothesis is tested with a case study of white-browed scrubwrens Sericornis frontalis and a review of the literature. 2,The scrubwren is a cooperatively breeding passerine with male helpers. Previous analyses revealed no effect of group size on reproductive success, but those analyses were restricted to groups with older females (Magrath & Yezerinac 1997). Here 7 years' data are used to contrast the effect of group size on reproductive success for yearling and older females. 3,Yearling females breeding in groups had more than double the seasonal reproductive success than those breeding in pairs, even after controlling for territory quality. However, group size still had no effect on the reproductive success of older females. Yearling females tended to survive better in groups, but older females tended to survive better in pairs, emphasizing this pattern. 4,Yearlings breeding in pairs were more likely to be found on poor-quality territories than those breeding in groups, exaggerating the already-strong effect of group size on yearling success. Older females were not affected significantly by territory quality. 5,Group size, territory quality and female age affected different components of seasonal reproductive success. Group size increased the success of individual nesting attempts, while both territory quality and female age affected the length of the breeding season, and thus the number of breeding attempts. 6,A sample of the literature on cooperative breeders shows that group size has a larger effect on reproductive success in poorer conditions, caused either by younger, inexperienced breeders or poorer environmental conditions. Scrubwrens therefore illustrate a widespread pattern, which provides an explanation for much of the variation in group-size effects among and within species. Clearly single estimates of group-size effects for species can be inadequate to test ideas about the evolution of cooperative breeding. [source] Estimates of maximum annual population growth rates (rm) of mammals and their application in wildlife managementJOURNAL OF APPLIED ECOLOGY, Issue 3 2010Jim Hone Summary 1.,The maximum annual population growth rate (rm) is a critical parameter in many models of wildlife dynamics and management. An important application of rm is the estimation of the maximum proportion of a population that can be removed to stop population growth (p). 2.,When rm cannot be estimated in the field, one option is to estimate it from demographic data. We evaluate the use of the relationship between rm and female age at first reproduction (,), which is independent of phylogeny, to estimate rm. We first demonstrate that the relationship between field and demographic estimates of rm is unbiased. We then show that the relationship provides an unbiased and simple method to estimate rm using data for 64 mammal species. We also show that p declines exponentially as , increases. 3.,We use the fitted relationship to estimate annual rm and p for 55 mammal species in Australia and New Zealand for which there are no field estimates of rm. The estimates differ by species but have low precision (wide 95% credible intervals CIs). Our estimate of rm for the Tasmanian devil Sarcophilus harrisii is high (0·6, 95% CI: 0·05,2·39) and suggests devils would become extinct if >0·34 of the population is removed annually (e.g. by facial tumour disease). Our estimate of rm (0·77, 95% CI: 0·71,1·05) for brushtail possum Trichosurus vulpecula is much greater than published estimates and highlights the need for further field estimates of rm for the species in New Zealand. 4.,Synthesis and applications. Since rm has not been estimated in the field for the majority of mammal species, our approach enables estimates with credible intervals for this important parameter to be obtained for any species for which female age at first reproduction is known. However, the estimates have wide 95% CIs. The estimated rm, and associated uncertainty can then be used in population and management models, perhaps most importantly to estimate the proportion that if removed annually would drive the population to extinction. Our approach can be used for taxa other than mammals. [source] Intrapopulation variation in reproduction by female eastern kingbirds Tyrannus tyrannus: the impacts of age, individual performance, and breeding siteJOURNAL OF AVIAN BIOLOGY, Issue 3 2004Michael T. Murphy I used data from a 13-year study of eastern kingbirds Tyrannus tyrannus from central New York, USA, to evaluate the relative impact of female age and body size on reproduction. I also calculated repeatabilities of reproductive traits for both females and the sites where they bred in an attempt to evaluate the relative contribution of each to intrapopulation variation in reproduction. Female age had a strong influence on timing of breeding (breeding date advanced by one day for each year of life), but was not a significant source of variation for clutch size, egg mass, number of young to hatch or fledge, or total seasonal production. Repeatabilities of breeding date for females and sites were both significant (0.284 and 0.181, respectively), but the only other significant repeatabilities were for female clutch size (0.282) and female egg mass (0.746). Among-year repeatabilities of breeding date for females who bred at two or more sites over their lifetime were as high as those for females that were site faithful. Thus, breeding date was probably affected independently by the female and site. No measure of productivity exhibited a repeatable pattern in comparisons made among females or sites. All reproductive traits were entered as dependent variables in a series of stepwise multiple regression analyses in an attempt to identify female properties (size, lifespan and condition) that might be linked proximately to differences in breeding statistics. I found that (a) large birds tended to breed the earliest, (b) clutch size was independent of female size, condition and lifespan, (c) female body size and egg size were correlated positively, but (d) production of young was independent of all measured female properties. Reproduction appears to be linked more closely to the female than to the site. Body size accounts for a portion of the repeatable portion of breeding date and egg mass, but most of the intrapopulation variation in these and other traits remained unexplained. [source] The influence of age on reproductive performance in the Brown ThornbillJOURNAL OF AVIAN BIOLOGY, Issue 1 2001David J. Green I examined age effects on reproduction in the Brown Thornbill Acanthiza pusilla in Canberra, Australia. I found that the reproductive performance of both males and females improved with age, although only age-related improvement in male performance had a significant effect on annual reproductive success. Reproductive success improved with male age as a result of improved performance during two stages of the breeding cycle: first-year males were less likely to fledge young than those aged two or more, while both first and second-year males were less successful at raising fledglings to independence than males of three or more. Male performance appears to improve over three years as they gain experience at provisioning nestlings and caring for fledglings without attracting predators, rather than as a direct result of improved foraging skills. In contrast, reproductive success only improved slightly with female age, although females of two or more years initiated their first clutch earlier in the season than one-year-old females, and tended to be more likely to re-nest if a breeding attempt failed. The poor performance of young females appears unlikely to be related to their foraging ability but may be associated with costs imposed by dispersing to a breeding vacancy earlier in the year. Although the reproductive performance of Brown Thornbills improves considerably with age I found no evidence that performance improved as a result of repeated breeding attempts with the same partner. [source] Drinking, Alcohol Problems and the Five-Year Recurrence and Incidence of Male to Female and Female to Male Partner ViolenceALCOHOLISM, Issue 1 2005Raul Caetano Background: This study examined the 5-year incidence and recurrence of male to female (MFPV) and female to male partner violence (FMPV) as well as their relationship with drinking and alcohol problems among intact couples in the United States. Methods: A national sample of couples 18 years of age or older were interviewed in 1995 and again in 2000. Results: Recurrence is slightly higher for FMPV (44%) than MFPV (39%), whereas incidence rates are similar for these two types of violence (MFPV, 5.7%; FMPV, 6%). Cross-tabulations show that a higher frequency of drinking five or more drinks on occasion is positively associated with the overall occurrence of MFPV and with both the recurrence and the overall occurrence of FMPV. Male alcohol problems are associated with a higher recurrence of MFPV and higher overall MFPV. Female alcohol problems are associated with incidence of FMPV. In multivariate analysis, black ethnicity, male unemployment, and severe physical abuse during childhood are associated with recurrence of MFPV. Black ethnicity, male unemployment, male employment status as "retired/other," female age, and couples in which the female drinks more are associated with recurrence of FMPV. Incidence of MFPV is associated with cohabitation, Hispanic ethnicity, and man's observation of violence between parents. Male unemployment, male observation of violence between parents, and man's drinking volume predict incidence of FMPV. Conclusions: Volume of drinking is the only alcohol indicator associated with intimate partner violence once the effects of other factors are controlled in multivariate analysis. Both MFPV and FMPV are areas of health disparity across whites, blacks, and Hispanics. Factors of risk that predict recurrence and incidence can be identified and used in prevention efforts. [source] Estimates of heritability for reproductive traits in captive rhesus macaque femalesAMERICAN JOURNAL OF PRIMATOLOGY, Issue 9 2010Christine Gagliardi Abstract Records from a colony of captive Indian rhesus macaques (Macaca mulatta) were used to estimate heritability for a number of reproductive traits. Records were based on a total of 7,816 births by 1,901 females from 1979 to 2007. Heritability was estimated with a linear animal model using a multiple trait derivative free REML set of programs. Because no male parents were identified, the numerator relationship matrix contained female kinships established over six generations. Reproductive traits included female age at the birth of the first, second and last infant, age at death, inter-birth intervals, number of infants born per female and infant survival. Heritability for each trait was estimated as the ratio of the additive genetic variance to phenotypic variance adjusted for significant fixed effects. Estimates of heritability for early reproduction ranged from 0.000±0.072 for birth interval after the first reproduction to 0.171±0.062 for age of female at the first infant. Higher estimates of heritability were found for female longevity [0.325±0.143] and for productivity of deceased females born before 1991 [0.221±0.138]. Heritability for infant survival ranged from 0.061±0.018 for survival from 30 days to 1 year to 0.290±0.050 for survival from birth to 30 days when adjusted to an underlying normal distribution. Eight of the 13 estimates of heritability for reproductive traits in this study were different from zero [P<0.05]. Generally, heritability estimates reported in this study for reproductive traits of captive rhesus macaque females are similar to those reported in the literature for free-ranging rhesus macaque females and for similar reproductive traits of other species. These estimates of heritability for reproductive traits appear to be among the first for a relatively large colony of captive rhesus macaque females. Am. J. Primatol. 72:811,819, 2010. © 2010 Wiley-Liss, Inc. [source] Monitoring population productivity in the saiga antelopeANIMAL CONSERVATION, Issue 4 2009A. Kühl Abstract Effective conservation requires a good understanding of factors causing variation in population growth rate. We here analyse the relationship between female age and fecundity in the saiga antelope Saiga tatarica tatarica, a critically endangered ungulate of the Eurasian steppes and semideserts, at both individual and population levels. Annual variation in age structure and twinning rates was investigated using long-term datasets, sampling a total of 3308 females in four populations over more than 40 years. Further, a new non-invasive method is presented, estimating twinning rates from both calves and placentas encountered during calving aggregation transects. At an individual level, the most parsimonious model for twinning rates included three age classes (1, 2 and ,3 years); however, the model with only two classes (1 and ,2 years) was competitive and particularly useful for monitoring because these two age classes can reliably be determined by direct observation in the field. Among yearlings, 77.4% were fecund and 11.7% twinned, whereas among older females 94.6% were fecund and 72.6% twinned. At a population level, annual variation in age structure (proportion ,2 years) correlated well with annual variation in twinning rate except in the north-west Pre-Caspian population. Our results suggest that the recent poaching-driven collapse in saiga numbers has potentially resulted in reductions in fecundity, which will have an impact on population growth rate. Our results highlight the potential for monitoring of twinning rate using non-invasive calving aggregation transects as a cost-effective additional tool to population counts for monitoring the status of this critically endangered species. These monitoring methods are also potentially transferable to other ungulate species. [source] Identification and Treatment in Obstetrical PatientsNURSING FOR WOMENS HEALTH, Issue 6 2006Lesa L.K. Chizawsky RN Eating disorders are well defined in females ages 14 to 24, and consist primarily of anorexia nervosa (AN) and bulimia nervosa (BN). Collectively, these two eating disorders are characterized by severe disturbances in eating behaviors and acute distress over body shape and weight. In AN, fear of weight gain coupled with a distorted body image leads to refusal to maintain a minimally accepted body weight (American Psychiatric Association [APA], 1994). Although women with BN also overvalue body size and shape, this disorder is characterized by episodes of binge eating followed by efforts to undo the binge episode (oral purging is the most widely known effort) (APA, 1994). Developmental, psychological, socioenvironmental and behavioral factors contribute to the complex development and persistence of AN and BN (Rosen & Neumark-Sztainer, 1998). [source] Urban-Rural Disparities in Injury Mortality in China, 2006THE JOURNAL OF RURAL HEALTH, Issue 1 2010Guoqing Hu PhD Abstract Context: Urban-rural disparity is an important issue for injury control in China. Details of the urban-rural disparities in fatal injuries have not been analyzed. Purpose: To target key injury causes that most contribute to the urban-rural disparity, we decomposed total urban-rural differences in 2006 injury mortality by gender, age, and cause. Methods: Mortality data came from the Chinese Vital Registration data, covering a sample of about 10% of the total population. The chi-square test was used to test the significance of urban-rural disparities. Findings: For all ages combined, the injury death rate for males was 60.1/100,000 in rural areas compared with 40.9 in urban areas; for females, the respective rates were 31.5 and 23.6/100,000. The greatest disparity was at age <1 year for both sexes, where the rate from unintentional suffocation in rural areas was more than twice the urban rate. The higher mortality from drowning among males of all ages and among females ages 1-24 and 35+ contributed substantially to the age-specific urban-rural disparities. For both sexes, transportation incidents and suicide were the most important contributors to higher rates among rural residents ages 15+. Conclusions: Unintentional suffocation, drowning, transportation incidents, and suicide not only are the major causes of injury death, but also play a key role in explaining the urban-rural disparities in fatal injuries. Further research is needed to identify factors leading to higher rural death rates and to explore economical and feasible interventions for reducing injuries and narrowing the urban-rural gap in injury mortality. [source] Endoscopic Treatment of Salivary Gland Injuries due to Facial Rejuvenation ProceduresTHE LARYNGOSCOPE, Issue 5 2008Oded Nahlieli DMD Abstract Objective: The purpose of this article is to describe innovative surgical techniques for treatment of salivary gland injuries caused by facial rejuvenation procedures. Methods: Between 2001 and 2007, a total of 14 patients, all females ages 46 to 70 who suffered from salivary gland injuries caused by facial rejuvenation procedures, were treated, primarily by an endoscopic-guided technique that involved location of the injury and endoscopic repair. Results: There were four types of postsurgical injuries of the salivary glands that were caused by operations for facial rejuvenation: 1) compression of salivary ducts with temporary swelling (n = 1); 2) laceration of the capsule of the salivary gland (n = 3); 3) stretching and compression of the ducts with penetration of the capsule of the duct leading to sialocele and long-term swelling (types 1 and 2 combined) (n = 5); and 4) complete cut or penetration of the main salivary duct or of one of its main branches resulting in sialocele (n = 5). The endoscopic technique treatment was successful in all cases. Conclusion: The main reasons for salivary gland injuries due to facial rejuvenation procedures in our patients were: poor anatomical identification of the border between the superficial muscular aponeurotic system (SMAS) and the parotid capsule; penetration of the salivary gland capsule by blunt or sharp dissection; unnecessary use of sharp-tip scissors; and a tear of the salivary duct by hooks during a face-lift procedure. Plastic surgeons should be aware of these complications and try to improve their techniques accordingly. To avoid atrophy of the salivary gland, once the diagnosis it made, it is advisable to send the patient to a maxillofacial or ENT surgeon skilled in endoscopy. [source] | |||||||||||||