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1.
In a study of the causes of abortion and stillbirth in a Holstein-Friesian herd, the most probable cause detected was a lethal gene transmitted through the pedigree line. Findings of this nature have already been reported both in the United States and Canada for the same line.Replacing the sires with others solved the problem, thus demonstrating a genetic etiology for abortion and stillbirth in this lineage. The differences noted in the time of fetal mortality may indicate the action of more than one gene or variable expressivity of the mutant gene.The importance of the data is discussed in terms of the elimination of genetic factors that cause fetal mortality.  相似文献   
2.
Stillbirth is an economically important trait on dairy farms. Knowledge of the consequences of, and the economic losses associated with stillbirth can help the producer when making management decisions. The objectives of this study were to determine the effects of stillbirth on productive and reproductive performance as well as financial losses due to stillbirth incidence in Iranian Holstein dairy farms. Economic and performance data were collected from nine Holstein dairy farms in Isfahan and Khorasan provinces of Iran from March 2008 to December 2013. The final data set included 160 410 calving records from 53 265 cows. A linear mixed model was developed to evaluate the effects of stillbirth on performance of primiparous and multiparous cows separately and overall. An economic model was used to estimate the economic losses due to stillbirth. The incidence of stillbirth cases per cow per year was 4.2% on average (3.4% to 6.8% at herd level). The least square means results showed that a case of stillbirth significantly (P<0.05) reduced 305-day milk production in multiparous cows and overall, but had no significant effects on primiparous cows production performance (P>0.05). Overall, a case of stillbirth reduced 305-day milk yield by 544.0±76.5 kg/cow per lactation. Stillbirth had no significant effects on 305-day fat and protein percentages in either primiparous or multiparous cows. Overall, cows that gave birth to stillborn calves had significantly increased days open by 14.6±2.6 days and the number of inseminations per conception by 0.2 compared with cows that gave birth to live calves (P<0.01). In general, the negative productive and reproductive effects associated with stillbirth were smaller and non-significant for primiparous cows compared with multiparous cows. The financial losses associated with stillbirth incidence averaged US$ 938 per case (range from $US 767 to $US 1189 in the nine investigated farms). The loss of a calf was not the only cost associated with stillbirth, as it accounted for 71.0% of the total cost. The costs of dystocia (7.6%) and culling and replacement expenses (6.3%) were the next most important costs associated with stillbirth. These results can be used to assess the potential return from management strategies to reduce the occurrence of stillbirths.  相似文献   
3.
Dystocia and stillbirth are significant causes of female and neonatal death in many species and there is evidence for a genetic component to both traits. Identifying causal mutations affecting these traits through genome wide association studies could reveal the genetic pathways involved and will be a step towards targeted interventions. Norwegian Red cattle are an ideal model breed for such studies as very large numbers of records are available. We conducted a genome wide association study for direct and maternal effects of dystocia and stillbirth using almost 1 million records of these traits. Genotyping costs were minimized by genotyping the sires of the recorded cows, and using daughter averages as phenotypes. A dense marker map containing 17 343 single nucleotide polymorphisms covering all autosomal chromosomes was utilized. The genotyped sires were assigned to one of two groups in an attempt to ensure independence between the groups. Associations were only considered validated if they occurred in both groups. Strong associations were found and validated on chromosomes 4, 5, 6, 9, 12, 20, 22 and 28. The QTL region on chromosome 6 was refined using LDLA analysis. The results showed that this chromosome most probably contains two QTL for direct effect on dystocia and one for direct effect on stillbirth. Several candidate genes may be identified close to these QTL. Of these, a cluster of genes expected to affect bone and cartilage formation (i.e. SPP1, IBSP and MEPE) are of particular interest and we suggest that these genes are screened in candidate gene studies for dystocia and stillbirth in cattle as well as other species.  相似文献   
4.
This is the first published report of twinning in a squirrel monkey (genus Saimiri). The mother survived but the twins, both male and close to full term, were stillborn  相似文献   
5.
Estimates of the burden of disease assess the mortality and morbidity that affect a population by producing summary measures of health such as quality‐adjusted life years (QALYs) and disability‐adjusted life years (DALYs). These measures typically do not include stillbirths (fetal deaths occurring during the later stages of pregnancy or during labor) among the negative health outcomes they count. Priority‐setting decisions that rely on these measures are therefore likely to place little value on preventing the more than three million stillbirths that occur annually worldwide. In contrast, neonatal deaths, which occur in comparable numbers, have a substantial impact on burden of disease estimates and are commonly seen as a pressing health concern. In this article we argue in favor of incorporating unintended fetal deaths that occur late in pregnancy into estimates of the burden of disease. Our argument is based on the similarity between late‐term fetuses and newborn infants and the assumption that protecting newborns is important. We respond to four objections to counting stillbirths: (1) that fetuses are not yet part of the population and so their deaths should not be included in measures of population health; (2) that valuing the prevention of stillbirths will undermine women's reproductive rights; (3) that including stillbirths implies that miscarriages (fetal deaths early in pregnancy) should also be included; and (4) that birth itself is in fact ethically significant. We conclude that our proposal is ethically preferable to current practice and, if adopted, is likely to lead to improved decisions about health spending.  相似文献   
6.
Background Non‐human primates, particularly baboons, are valuable as animal models for reproductive research, because of their similarity to humans. Knowledge of colony‐specific pregnancy and neonatal outcomes is essential for interpretation of such research. Methods A retrospective review of the reproductive records of the Australian National Baboon Colony (ANBC) from 1994 to 2006 was performed. Results The overall live birth rate was over 70% of recognized pregnancies. Pregnancy loss was due to equal proportions of spontaneous abortion and stillbirth, and was not affected by maternal age or parity. Stillbirth rates were increased by the use of animals in novel late pregnancy experimental protocols. Neonatal mortality rates were low overall, but significantly higher in primiparous compared with multiparous mothers (P < 0.05). There were no cases of maternal mortality. Conclusions The success of the ANBC breeding programme is demonstrated by the low rate of pregnancy loss, high neonatal survival rate and lack of maternal mortality.  相似文献   
7.
Non-invasive methods for monitoring reproductive status of chimpanzee based on the measurement of urinary steroids and gonadotropins were examined. A typical pre-ovulatory urinary estrone conjugate (E1C) surge and post-ovulatory increase in pregnandiol glucuronide (PdG) were seen during the menstrual cycle. Urinary follicle stimulating hormone (FSH) showed two peaks over the infertile menstrual cycle. The earliest changes indicating pregnancy were a coincident rise in E1C and chorionic gonadotropin (CG) levels and a concomitant fall in FSH levels. Urinary PdG levels showed a prolonged rise. Urinary E1C in the pregnant chimpanzee was higher than during the menstrual cycle and increased with advancing gestation, with maximum levels occurring near term. In the case of stillbirth, E1C and CG levels from mid- through late-pregnancy were low and the prepartum progressive increase in E1C was not shown. The data presented here are of great practical value in captive breeding management of chimpanzees.  相似文献   
8.
The objective of the study was to estimate genetic trends from 1977 to 1998 in the French Large White (LW) breed for stillbirth and associated traits measured at farrowing using frozen semen. Two groups of pigs (G77 and G98) were obtained by inseminating LW sows with semen from LW boars born either in 1977 or in 1998. A second generation was produced by inter se mating in each group. Farrowing was thoroughly supervised through both direct observations and video recording all long farrowing on a total of 137 first- and second-parity litters produced by sows from this second generation (68 G77 and 69 G98 litters, respectively). Measurements included birth time, weight and birth characteristics (including orientation, presence of cyanosis or oedema, membrane obstruction, umbilical cord length/content) of each piglet, as well as sow traits (weight and backfat thickness, farrowing duration, litter size and within-litter variation of weights at birth). The data were analysed using linear or generalised linear mixed models, according to the definition of the trait (continuous or binary data). The importance of several effects to piglet probability of stillbirth was then quantified by computing the reduction of variance associated with the addition of each effect in the model. Litter size did not significantly differ in first parity, but was higher in G98 second-parity sows: the differences for global (including pre partum dead piglets) and total numbers of piglets born per litter were +2.3 ± 1.1 and +1.3 ± 0.6, respectively. G98 sows also had a higher number of stillbirths in both parities (+0.7 ± 0.3 stillborn per litter). Piglets from G98 litters were heavier at birth (+130 ± 40 g for birth weight adjusted for litter size), without any increase in within-litter heterogeneity of birth weight. No significant difference was detected between G77 and G88 groups for farrowing length and the distribution of time interval between piglet births. G98 stillborn piglets had longer and more often empty umbilical cords at birth. G98 piglets born alive also had more often umbilical nodes than G77 piglets. These characteristics were considered as indicators of increased farrowing difficulties and risk of hypoxia at birth in G98 pigs. Time of birth of each piglet, sow fatness at farrowing and time of first placenta expulsion were the main factors of variation of the piglet's probability of stillbirth.  相似文献   
9.
More and more epidemiologic and experimental data support the notion that Ljungan virus (LV), originally isolated from some rodent populations in Sweden, Denmark, and the United States, plays an important role in stillbirth and fetal malformation. Mouse dams infected with LV may result in uterine resorption and perinatal deaths that may cross generations, and their offspring may suffer high rates of malformations including cranial, brain, and limb malformations. In humans, researches founded that LV infection is related to malformation, intrauterine fetal death, and even central nervous system malformation. Although molecularly characterized, little is known about the biophysical nature of LV. Consequently, the role of LV infections in sudden infant death syndrome is still confusing, and the mechanism of how LV infections cause diseases is not clear. More research is clearly necessary to explore the mechanisms of LV infection in human and animal diseases to bring improvement to the clinical outcomes. Birth Defects Research (Part C) 105:81–85, 2015. © 2015 Wiley Periodicals, Inc.  相似文献   
10.
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