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Journal of Dairy Science Sep 2022The cumulative improvement achieved in the genetic merit for reproductive performance in dairy populations will likely improve dairy cow longevity; therefore, it is time...
The cumulative improvement achieved in the genetic merit for reproductive performance in dairy populations will likely improve dairy cow longevity; therefore, it is time to reassess whether linear type traits are still suitable predictors of survival in an aging dairy cow population. The objective of the present study was therefore to estimate the genetic correlations between linear type traits and survival from one parity to the next and, in doing so, evaluate if those genetic correlations change with advancing parity. After edits, 152,894 lactation survival records (first to ninth parity) were available from 52,447 Holstein-Friesian cows, along with linear type trait records from 52,121 Holstein-Friesian cows. A series of bivariate random regression models were used to estimate the genetic covariances between survival in different parities and each linear type trait. Heritability estimates for survival per parity ranged from 0.02 (SE = 0.004; first parity) to 0.05 (SE = 0.01; ninth parity). Pairwise genetic correlations between survival among different parities varied from 0.42 (first and ninth parity) to 1.00 (eighth to ninth parity), with the strength of these genetic correlations being inversely related to the interval between the compared parities. The genetic correlations between survival and the individual linear type traits varied across parities for 9 of the 20 linear type traits examined, but the correlations with only 3 of these linear type traits strengthened as the cows aged; these 3 traits were rear udder height, teat length, and udder depth. Given that linear type traits are frequently scored in first parity and are genetically correlated with survival in older parities, they may be suitable early predictors of survival, especially for later parity cows. Additionally, the direction of the genetic correlations between survival and rear udder height, teat length, and udder depth did not change between parities; hence, selection for survival in older parities using these linear type traits should not hinder genetic improvement for survival in younger parities.
Topics: Animals; Cattle; Female; Lactation; Longevity; Mammary Glands, Animal; Milk; Parity; Phenotype; Pregnancy
PubMed: 35879159
DOI: 10.3168/jds.2022-22026 -
Journal of Dairy Science Nov 2020Ketosis is a metabolic disorder of increasing importance in high-yielding dairy cows, but accurate population-wide binary health trait recording is difficult to...
Ketosis is a metabolic disorder of increasing importance in high-yielding dairy cows, but accurate population-wide binary health trait recording is difficult to implement. Against this background, proper Gaussian indicator traits, which can be routinely measured in milk, are needed. Consequently, we focused on the ketone bodies acetone and β-hydroxybutyrate (BHB), measured via Fourier-transform infrared spectroscopy (FTIR) in milk. In the present study, 62,568 Holstein cows from large-scale German co-operator herds were phenotyped for clinical ketosis (KET) according to a veterinarian diagnosis key. A sub-sample of 16,861 cows additionally had first test-day observations for FTIR acetone and BHB. Associations between FTIR acetone and BHB with KET and with test-day traits were studied phenotypically and quantitative genetically. Furthermore, we estimated SNP marker effects for acetone and BHB (application of genome-wide association studies) based on 40,828 SNP markers from 4,384 genotyped cows, and studied potential candidate genes influencing body fat mobilization. Generalized linear mixed models were applied to infer the influence of binary KET on Gaussian-distributed acetone and BHB (definition of an identity link function), and vice versa, such as the influence of acetone and BHB on KET (definition of a logit link function). Additionally, linear models were applied to study associations between BHB, acetone and test-day traits (milk yield, fat percentage, protein percentage, fat-to-protein ratio and somatic cell score) from the first test-day after calving. An increasing KET incidence was statistically significant associated with increasing FTIR acetone and BHB milk concentrations. Acetone and BHB concentrations were positively associated with fat percentage, fat-to-protein ratio and somatic cell score. Bivariate linear animal models were applied to estimate genetic (co)variance components for KET, acetone, BHB and test-day traits within parities 1 to 3, and considering all parities simultaneously in repeatability models. Pedigree-based heritabilities were quite small (i.e., in the range from 0.01 in parity 3 to 0.07 in parity 1 for acetone, and from 0.03-0.04 for BHB). Heritabilites from repeatability models were 0.05 for acetone, and 0.03 for BHB. Genetic correlations between acetone and BHB were moderate to large within parities and considering all parities simultaneously (0.69-0.98). Genetic correlations between acetone and BHB with KET from different parities ranged from 0.71 to 0.99. Genetic correlations between acetone across parities, and between BHB across parities, ranged from 0.55 to 0.66. Genetic correlations between KET, acetone, and BHB with fat-to-protein ratio and with fat percentage were large and positive, but negative with milk yield. In genome-wide association studies, we identified SNP on BTA 4, 10, 11, and 29 significantly influencing acetone, and on BTA 1 and 16 significantly influencing BHB. The identified potential candidate genes NRXN3, ACOXL, BCL2L11, HIBADH, KCNJ1, and PRG4 are involved in lipid and glucose metabolism pathways.
Topics: 3-Hydroxybutyric Acid; Acetone; Animals; Cattle; Cattle Diseases; Female; Genome-Wide Association Study; Genotype; Glucose; Ketone Bodies; Ketosis; Lactation; Lipid Metabolism; Milk; Parity; Pedigree; Phenotype; Pregnancy
PubMed: 32952022
DOI: 10.3168/jds.2020-18339 -
American Journal of Obstetrics &... Jan 2022The rates of severe maternal morbidity and mortality in the United States exceed those in other high-income nations. To aid providers and hospitals in recognizing the...
BACKGROUND
The rates of severe maternal morbidity and mortality in the United States exceed those in other high-income nations. To aid providers and hospitals in recognizing the risk factors, there have been multiple attempts to develop stratification systems for morbidity based on maternal comorbidities. However, most women giving birth are healthy and do not have comorbidities to suggest that they are at an increased risk for severe maternal morbidity. There are small but inherent maternal risks to labor, and the events after admission may further influence a woman's risk for morbidity even for those initially at a low risk.
OBJECTIVE
To determine if the incorporation of intrapartum factors known at the start of the second stage of labor improves the predictive performance of a comorbidity-based risk tool for severe maternal morbidity.
STUDY DESIGN
This is a retrospective cohort study of women at 8 hospitals in a single health system between July 1, 2016, and June 30, 2020. The women had term, singleton gestations and were admitted in labor and reached the second stage. The primary outcome was severe maternal morbidity. We compared logistic regression models using a validated risk-scoring tool (the Expanded Obstetric Comorbidity Score, which uses diagnosis codes for maternal comorbidities and pregnancy characteristics to predict maternal morbidity) with a model that included the Expanded Obstetric Comorbidity Score combined with parity and intrapartum factors. The intrapartum factors included labor induction or augmentation, length of labor, prolonged rupture of membranes, the presence of meconium-stained amniotic fluid, and gestational age. The hospitals were divided into a training (n=4) and testing (n=4) set to evaluate the predictive model performance. Discrimination was assessed by calculating the area under the receiver operating curve and calibration via calibration plots. Similar model comparisons were performed in a subgroup of women, who the Expanded Obstetric Comorbidity Score predicted to be at low risk for morbidity.
RESULTS
This analysis included 33,770 deliveries from the 8 hospitals; severe maternal morbidity occurred in 498 (1.5%) deliveries. The model performance is reported among the testing set (n=15,350). Using the Expanded Obstetric Comorbidity Score alone, the area under the receiver operating curve was 0.676 (95% confidence interval, 0.636-0.716) and 155 (71%) events occurred among individuals above the median predicted risk. When combining intrapartum factors, the area under the receiver operating curve increased to 0.729, (95% confidence interval, 0.693-0.764) and 171 (78%) events occurred among individuals above the median predicted risk. The significant factors that were associated with severe maternal morbidity in this combined model included the Expanded Obstetric Comorbidity Score, length of labor, and the presence of meconium-stained amniotic fluid. The area under the receiver operating curve for the model with intrapartum factors was significantly higher than the models using the Expanded Obstetric Comorbidity Score alone (P<.001).
CONCLUSION
The incorporation of intrapartum factors along with a validated risk tool (Expanded Obstetric Comorbidity Score) improved the ability to predict severe maternal morbidity at the start of the second stage. These findings emphasize the evolution of a woman's risk during her labor course and suggests that the prediction of maternal risk can be improved by considering intrapartum factors.
Topics: Female; Humans; Labor, Induced; Labor, Obstetric; Parity; Parturition; Pregnancy; Retrospective Studies
PubMed: 34517146
DOI: 10.1016/j.ajogmf.2021.100485 -
Gaceta Sanitaria 2017Birthweight by gestational age charts enable fetal growth to be evaluated in a specific population. Given that maternal profile and obstetric practice have undergone a...
OBJECTIVE
Birthweight by gestational age charts enable fetal growth to be evaluated in a specific population. Given that maternal profile and obstetric practice have undergone a remarkable change over the past few decades in Spain, this paper presents new Spanish reference percentile charts stratified by gender, parity and type of delivery. They have been prepared with data from the 2010-2014 period of the Spanish Birth Statistics Bulletin.
METHODS
Reference charts have been prepared using the LMS method, corresponding to 1,428,769 single, live births born to Spanish mothers. Percentile values and mean birth weight are compared among newborns according to gender, parity and type of delivery.
RESULTS
Newborns to primiparous mothers show significantly lower birthweight than those born to multiparous mothers (p<0.036). Caesarean section was associated with a substantially lower birthweight in preterm births (p<0.048), and with a substantially higher birthweight for full-term deliveries (p<0.030). Prevalence of small for gestational age is significantly higher in newborns born by Caesarean section, both in primiparous (p<0.08) and multiparous mothers (p<0.027) and, conversely, the prevalence of large for gestational age among full-term births is again greater both in primiparous (p<0.035) and in multiparous mothers (p<0.007).
CONCLUSIONS
Results support the consideration of establishing parity and type of delivery-specific birthweight references. These new charts enable a better evaluation of the impact of the demographic, reproductive and obstetric trends currently in Spain on fetal growth.
Topics: Birth Weight; Cesarean Section; Delivery, Obstetric; Female; Gestational Age; Growth Charts; Humans; Infant, Newborn; Male; Parity; Spain
PubMed: 28160963
DOI: 10.1016/j.gaceta.2016.09.016 -
Journal of Dairy Science Jan 2021Milk yield dynamics during perturbations reflect how cows respond to challenges. This study investigated the characteristics of 62,406 perturbations from 16,604...
Milk yield dynamics during perturbations reflect how cows respond to challenges. This study investigated the characteristics of 62,406 perturbations from 16,604 lactation curves of dairy cows milked with an automated milking system at 50 Belgian, Dutch, and English farms. The unperturbed lactation curve representing the theoretical milk yield dynamics was estimated with an iterative procedure fitting a model on the daily milk yield data that was not part of a perturbation. Perturbations were defined as periods of at least 5 d of negative residuals having at least 1 day that the total daily milk production was below 80% of the estimated unperturbed lactation curve. Every perturbation was characterized and split in a development and a recovery phase. Based hereon, we calculated both the characteristics of the perturbation as a whole, and the duration, slopes, and milk losses in the phases separately. A 2-way ANOVA followed by a pairwise comparison of group means was carried out to detect differences between these characteristics in different lactation stages (early, mid-early, mid-late, and late) and parities (first, second, and third or higher). On average, 3.8 ± 1.9 (mean ± standard deviation) perturbations were detected per lactation in the first 305 d after calving, corresponding to an estimated 92.1 ± 135.8 kg of milk loss. Only 1% of the lactations had no perturbations. On average, 2.3 kg of milk was lost per day in the development phase, while the recovery phase corresponded to an average increase in milk production of 1.5 kg/d, and these phases lasted an average of 10.1 and 11.6 d, respectively. Perturbation characteristics were significantly different across parity and lactation stage groups, and early and mid-early perturbations in higher parities were found to be more severe with faster development rates, slower recovery rates, and higher milk losses. The method to characterize perturbations can be used for precision phenotyping purposes that look into the response of cows to challenges or that monitor applications (e.g., to evaluate the development and recovery of diseases and how these are affected by preventive actions or treatments).
Topics: Animals; Automation; Cattle; Dairying; Female; Lactation; Milk; Parity; Pregnancy
PubMed: 33189288
DOI: 10.3168/jds.2020-19195 -
Journal of Clinical Hypertension... Nov 2021The effect of live birth/parity number on incident hypertension was investigated among Iranian parous women aged 30-70 years. The study population included 2188...
The effect of live birth/parity number on incident hypertension was investigated among Iranian parous women aged 30-70 years. The study population included 2188 normotensive women who were enrolled in 1999-2001. They were followed for incident hypertension (based on JNC 7 report) by 3-year intervals up to April 2018. Multivariable Cox proportional hazard models, adjusted for a wide set of potential hypertension risk factors, reproductive factors, and pregnancy complications, were applied to estimate hazard ratios (HRs) and 95% confidence intervals (CIs) of the number of parity/live birth(s) for incident hypertension. Additionally, as a sensitivity analysis, age-scale Cox regression was also done. During a median follow-up of 13.5 years, 935 incident hypertension have occurred. Compared to those with two live births, the participants who had 3 and ≥4 live births were at higher risk of hypertension development by the HRs of 1.25 [95% CI: 1.02-1.55] and 1.39 [1.12-1.72], respectively, in the full-adjusted model. Moreover, each additional live birth increased the risk of hypertension by a HR of 1.06 [95%CI: 1.02-1.11]. Results of parity number were also similar. Considering age as time scale also did not change the results generally. The authors found a significant interaction between live birth/parity number and age groups; the adverse effect of higher live birth/parity numbers on hypertension development was mainly found among those aged < 50 years. To sum up, compared to the live birth/parity number of two, Iranian women with ≥3 live birth/parity had a higher risk of incident hypertension; the issue was more prominent among younger mothers.
Topics: Female; Follow-Up Studies; Humans; Hypertension; Iran; Live Birth; Middle Aged; Parity; Pregnancy; Risk Factors
PubMed: 34657376
DOI: 10.1111/jch.14369 -
Journal of Dairy Science Jul 2022Anogenital distance (AGD) has been defined in dairy cows as the distance from the center of the anus to the base of the clitoris. Initial reports on nulliparous Holstein...
Anogenital distance (AGD) has been defined in dairy cows as the distance from the center of the anus to the base of the clitoris. Initial reports on nulliparous Holstein heifers and first- and second-parity Holstein cows have found inverse relationships between AGD and measures of fertility. Our primary objective was to determine the relationship between AGD and measures of fertility in a larger population of North American Holstein cows to validate our previous finding that AGD is inversely related to fertility. Secondary objectives were to determine the associations between AGD and parity, and milk yield. Using digital calipers, we measured AGD in 4,709 Holstein cows [mean ± standard deviation (SD); parity 2.3 ± 1.4; days in milk (DIM) 154 ± 94; 305-d mature equivalent (ME) milk yield 13,759 ± 2,188 kg] from 18 herds in Western Canada and 1 herd in the USA. Anogenital distance (mm) was normally distributed with a mean (±SD) of 132 ± 12, ranging from 95 to 177, and a median of 133. Anogenital distance was linearly but inversely associated with pregnancy to first artificial insemination (P/AI1). For every 1-mm increase in AGD, the estimated probability of P/AI1 decreased by 0.8%. The optimum AGD cut-point that predicted probability of P/AI1 with sensitivity and specificity of 45 and 55%, respectively, was 129 mm. Consequently, data were categorized into either short (≤129) or long (>129) AGD groups across parities, and associations between AGD, parity (first, second, and third+), and fertility measures were determined. Rates of P/AI1 were greater (36 vs. 30%) in short- than in long-AGD cows; short-AGD cows required fewer AI per conception (2.3 vs. 2.4) and had fewer days open (137 vs. 142), and a greater proportion of short-AGD cows (67 vs. 64%) was pregnant by 150 DIM compared with long-AGD cows. The rates of pregnancy up to 150 (hazard ratio of 0.91) and 250 DIM (hazard ratio of 0.93) were smaller in long- than in short-AGD cows. Anogenital distance had a weak positive association with both parity (r = 0.22) and 305-d ME milk yield (r = 0.04). Results indicate an inverse relationship between AGD and measures of fertility in lactating cows, validating our earlier report. We infer that although selecting cows for short AGD is expected to have an adverse effect on milk yield, the anticipated gain in fertility will outweigh the small decline in milk yield, strengthening the potential of AGD as a novel reproductive phenotype for use in future breeding programs to improve fertility.
Topics: Animals; Cattle; Female; Fertility; Insemination, Artificial; Lactation; Milk; North America; Parity; Pregnancy; Reproduction
PubMed: 35599035
DOI: 10.3168/jds.2021-20827 -
American Journal of Public Health Sep 2017
Topics: Artifacts; Female; Humans; Longevity; Maternal Age; Parity; Pregnancy; United States; Women's Health
PubMed: 28787215
DOI: 10.2105/AJPH.2017.303965 -
Scientific Reports Jan 2016To quantitatively assess the association between parity and all-cause mortality, we conducted a meta-analysis of cohort studies. Relevant reports were identified from... (Meta-Analysis)
Meta-Analysis
To quantitatively assess the association between parity and all-cause mortality, we conducted a meta-analysis of cohort studies. Relevant reports were identified from PubMed and Embase databases. Cohort studies with relative risks (RRs) and 95% confidence intervals (CIs) of all-cause mortality in three or more categories of parity were eligible. Eighteen articles with 2,813,418 participants were included. Results showed that participants with no live birth had higher risk of all-cause mortality (RR= 1.19, 95% CI = 1.03-1.38; I(2) = 96.7%, P < 0.001) compared with participants with one or more live births. Nonlinear dose-response association was found between parity and all-cause mortality (P for non-linearity < 0.0001). Our findings suggest that moderate-level parity is inversely associated with all-cause mortality.
Topics: Cause of Death; Cohort Studies; Female; Humans; Male; Mortality; Odds Ratio; Parity; Population Surveillance; Pregnancy
PubMed: 26758416
DOI: 10.1038/srep19351 -
Scientific Reports Aug 2015Parity has been shown to inversely associate with cardiovascular disease (CVD) mortality, but the evidence of epidemiological studies is still controversial. Therefore,... (Meta-Analysis)
Meta-Analysis
Parity has been shown to inversely associate with cardiovascular disease (CVD) mortality, but the evidence of epidemiological studies is still controversial. Therefore, we quantitatively assessed the relationship between parity and CVD mortality by summarizing the evidence from prospective studies. We searched MEDLINE (PubMed), EMBASE and ISI Web of Science databases for relevant prospective studies of parity and CVD mortality through the end of March 2015. Fixed- or random-effects models were used to estimate summary relative risks (RRs) and 95% confidence intervals (CIs). Heterogeneity among studies was assessed using the I(2) statistics. All statistical tests were two-sided. Ten prospective studies were included with a total of 994,810 participants and 16,601 CVD events. A borderline significant inverse association was observed while comparing parity with nulliparous, with summarized RR = 0.79 (95% CI: 0.60-1.06; I(2) = 90.9%, P < 0.001). In dose-response analysis, we observed a significant nonlinear association between parity number and CVD mortality. The greatest risk reduction appeared when the parity number reached four. The findings of this meta-analysis suggests that ever parity is inversely related to CVD mortality. Furthermore, there is a statistically significant nonlinear inverse association between parity number and CVD mortality.
Topics: Adult; Cardiovascular Diseases; Cohort Studies; Female; Humans; Middle Aged; Parity; Parturition; Pregnancy; Risk Factors; Young Adult
PubMed: 26299306
DOI: 10.1038/srep13411