Meta-analysis of genetic-parameter estimates for reproduction, growth and carcass traits in Nellore cattle by using a random-effects model

2018 ◽  
Vol 58 (9) ◽  
pp. 1575 ◽  
Author(s):  
Hinayah Rojas de Oliveira ◽  
Henrique Torres Ventura ◽  
Edson Vinícius Costa ◽  
Mariana Alencar Pereira ◽  
Renata Veroneze ◽  
...  

Meta-analysis based on a random-effects model is used to summarise and overcome the variability between divergent parameter estimates. We proposed a meta-analysis of published heritability and genetic-correlation estimates for reproduction, growth and carcass traits in purebred Nellore cattle. In total, 197 heritability and 107 genetic-correlation estimates from 62 scientific publications were used here. Most of traits (gestation length; weights at birth, 120, 210, 365 and 550 days of age; mature weight and all carcass traits) presented direct heritability estimates ranging from 0.20 to 0.40. Age at first calving presented the lowest value among direct heritabilities (0.1498); whereas the higher values (>0.40) were found for scrotal circumference at different ages and for weight at 450 days of age. Low maternal heritability estimates (ranging from 0.06 to 0.11) were observed for all growth traits. With the exception of correlation estimates involving the age at first calving, all other correlations were positive. High correlations (>0.85) were found mainly for the same trait at different ages. The results reported here will give support to genetic evaluations when reliable estimates for different traits in purebred Nellore cattle are not available.

Genetics ◽  
1996 ◽  
Vol 143 (3) ◽  
pp. 1409-1416 ◽  
Author(s):  
Kenneth R Koots ◽  
John P Gibson

Abstract A data set of 1572 heritability estimates and 1015 pairs of genetic and phenotypic correlation estimates, constructed from a survey of published beef cattle genetic parameter estimates, provided a rare opportunity to study realized sampling variances of genetic parameter estimates. The distribution of both heritability estimates and genetic correlation estimates, when plotted against estimated accuracy, was consistent with random error variance being some three times the sampling variance predicted from standard formulae. This result was consistent with the observation that the variance of estimates of heritabilities and genetic correlations between populations were about four times the predicted sampling variance, suggesting few real differences in genetic parameters between populations. Except where there was a strong biological or statistical expectation of a difference, there was little evidence for differences between genetic and phenotypic correlations for most trait combinations or for differences in genetic correlations between populations. These results suggest that, even for controlled populations, estimating genetic parameters specific to a given population is less useful than commonly believed. A serendipitous discovery was that, in the standard formula for theoretical standard error of a genetic correlation estimate, the heritabilities refer to the estimated values and not, as seems generally assumed, the true population values.


2021 ◽  
pp. 219256822110308
Author(s):  
Andrew Platt ◽  
Mostafa H. El Dafrawy ◽  
Michael J. Lee ◽  
Martin H. Herman ◽  
Edwin Ramos

Study Design: Systematic review and meta-analysis. Objectives: Indications for surgical decompression of gunshot wounds to the lumbosacral spine are controversial and based on limited data. Methods: A systematic review of literature was conducted to identify studies that directly compare neurologic outcomes following operative and non-operative management of gunshot wounds to the lumbosacral spine. Studies were evaluated for degree of neurologic improvement, complications, and antibiotic usage. An odds ratio and 95% confidence interval were calculated for dichotomous outcomes which were then pooled by random-effects model meta-analysis. Results: Five studies were included that met inclusion criteria. The total rate of neurologic improvement was 72.3% following surgical intervention and 61.7% following non-operative intervention. A random-effects model meta-analysis was carried out which failed to show a statistically significant difference in the rate of neurologic improvement between surgical and non-operative intervention (OR 1.07; 95% CI 0.45, 2.53; P = 0.88). In civilian only studies, a random-effects model meta-analysis failed to show a statistically significant difference in the rate of neurologic improvement between surgical and non-operative intervention (OR 0.75; 95% CI 0.21, 2.72; P = 0.66). Meta-analysis further failed to show a statistically significant difference in the rate of neurologic improvement between patients with either complete (OR 4.13; 95% CI 0.55, 30.80; P = 0.17) or incomplete (OR 0.38; 95% CI 0.10, 1.52; P = 0.17) neurologic injuries who underwent surgical and non-operative intervention. There were no significant differences in the number of infections and other complications between patients who underwent surgical and non-operative intervention. Conclusions: There were no statistically significant differences in the rate of neurologic improvement between those who underwent surgical or non-operative intervention. Further research is necessary to determine if surgical intervention for gunshot wounds to the lumbosacral spine, including in the case of retained bullet within the spinal canal, is efficacious.


2021 ◽  
Vol 36 (Supplement_1) ◽  
Author(s):  
P Ioannidou ◽  
J Bosdou ◽  
D Papanikolaou ◽  
D Goulis ◽  
A Lambropoulos ◽  
...  

Abstract Study question Does oral antioxidant supplementation improve sperm quality in infertile men with varicocele who have not undergone surgical repair? Summary answer Oral antioxidant supplementation improves sperm concentration and motility in infertile men with varicocele who have not undergone surgical repair. What is known already: Benefit from oral antioxidant supplementation has been shown in infertile men with varicocele following surgical repair. Similarly, oral antioxidant supplementation has been suggested in infertile men with varicocele who have not undergone surgical repair. However, its effect currently remains controversial. Study design, size, duration A literature search was performed until January 2021 aiming to identify prospective studies evaluating the use of oral antioxidant supplementation alone or in combination in men with varicocele who have not undergone surgical repair. Participants/materials, setting, methods Seven prospective studies were identified, published between 1987 and 2018, including 278 infertile men with varicocele who had not undergone surgical repair. The number of patients included ranged from 20 to 65. Sperm analysis, evaluating sperm concentration, motility and morphology was performed in these studies before and after oral antioxidant supplementation. Meta-analysis of weighted data was performed using random effects model. Results are reported as weighted mean difference (WMD) with 95% confidence interval (CI). Main results and the role of chance Seven studies were included in the systematic review. Oral antioxidant supplementation was performed by a combination of pentoxifylline, zinc and folic acid (single study), a combination of l-carnitine, fumarate, acetyl-l-carnitine, fructose, CoQ, vitamin C, zinc, folic acid and vitamin B12 (single study), a combination of L-Carnitine, vitamin C, coenzyme Q10, vitamin E, vitamin B9, vitamin B12, zinc , and selenium, l-carnitine (single study), or sole treatment with acetyl-l-carnitine (single study), L-Carnitine (single study), Coenzyme Q10 (single study) or zinc sulfate (single study). For the purpose of meta-analysis, the effect of oral antioxidant supplementation was evaluated after three months of treatment. Oral antioxidant supplementation significantly increased sperm concentration (WMD +5.65x106/ml 95% CI: +1.11 to + 10.12 p = 0.01, random effects model) and motility (WMD +4.30%, 95% CI: +0.86 to + 7.74 p = 0.01, random effects model) in infertile men with varicocele who had not undergone surgical repair. On the other hand, no significance difference was observed in sperm morphology (WMD +3.9%, 95% CI: –0.16 to + 8.04 p = 0.06, random effects model) and volume (WMD +0.53ml, 95% CI: 0.0 to + 1.0 p = 0.052, random effects model). Limitations, reasons for caution The number of relevant trials and that of patients included is small to allow for solid conclusions to be drawn. Moreover, although different oral antioxidants have been administered in infertile who had not undergone surgical repair, subgroup analysis was not feasible. Wider implications of the findings: Currently, limited evidence supports the use of oral antioxidants in the treatment of men with varicocele, who have not undergone surgical repair. Although the benefit in sperm concentration and motility appears to be modest, it might be important regarding achievement of pregnancy in these men. Trial registration number Not applicable


Cephalalgia ◽  
2014 ◽  
Vol 35 (1) ◽  
pp. 63-72 ◽  
Author(s):  
Amy A Gelfand ◽  
Peter J Goadsby ◽  
I Elaine Allen

Context Infant colic is a common and distressing disorder of early infancy. Its etiology is unknown, making treatment challenging. Several articles have suggested a link to migraine. Objective The objective of this article was to perform a systematic review and, if appropriate, a meta-analysis of the studies on the relationship between infant colic and migraine. Data sources Studies were identified by searching PubMed and ScienceDirect and by hand-searching references and conference proceedings. Study selection For the primary analysis, studies specifically designed to measure the association between colic and migraine were included. For the secondary analysis, studies that collected data on colic and migraine but were designed for another primary research question were also included. Data extraction Data were abstracted from the original studies, through communication with study authors, or both. Two authors independently abstracted data. Main outcomes and measures The main outcome measure was the association between infant colic and migraine using both a fixed-effects model and a more conservative random-effects model. Results Three studies were included in the primary analysis; the odds ratio for the association between migraine and infant colic was 6.5 (4.6–8.9, p < 0.001) for the fixed-effects model and 5.6 (3.3–9.5, p = 0.004) for the random-effects model. In a sensitivity analysis wherein the study with the largest effect size was removed, the odds ratio was 3.6 (95% CI 1.7–7.6, p = 0.001) for both the fixed-effects model and random-effects model. Conclusions In this meta-analysis, infant colic was associated with increased odds of migraine. If infant colic is a migrainous disorder, this would have important implications for treatment. The main limitation of this meta-analysis was the relatively small number of studies included.


2021 ◽  
Vol 99 (Supplement_1) ◽  
pp. 158-159
Author(s):  
Chad A Russell ◽  
E J Pollak ◽  
Matthew L Spangler

Abstract The commercial beef cattle industry relies heavily on the use of natural service sires. Either due to the size of breeding herds or to safe-guard against injury during the breeding season, multiple-sire breeding pastures are utilized. Although each bull might be given an equal opportunity to produce offspring, evidence suggest that there is substantial variation in the number of calves sired by each bull in a breeding pasture. DNA-based paternity assignment enables correct assignment of calves to their respective sires in multi-sire pastures and presents an opportunity to investigate the degree to which this trait complex is under genetic control. Field data from a large commercial ranch were used to estimate genetic parameters for calf count (CC; n=623) and yearling scrotal circumference (SC; n=1962) using univariate and bivariate animal models. Average CC and SC were 12.1±11.1 calves and 35.4±2.30 cm, respectively. Average number breeding seasons per bull and bulls per contemporary group were 1.40 and 24.9, respectively. The model for CC included fixed effects of age during the breeding season (in years) and contemporary group (concatenation of breeding pasture and year). Random effects included additive genetic and permanent environmental effects, and a residual. The model for SC included fixed effects of age (in days) and contemporary group (concatenation of month and year of measurement). Random effects included an additive genetic effect and a residual. Univariate model heritability estimates for CC and SC were 0.237±0.156 and 0.456±0.072, respectively. Similarly, the bivariate model resulted in heritability estimates for CC and SC of 0.240±0.155 and 0.461±0.072, respectively. Repeatability estimates for CC from univariate and bivariate models were 0.517±0.054 and 0.518±0.053, respectively. The estimate of genetic correlation between CC and SC was 0.270±0.220. Parameter estimates suggest that both CC and SC would respond favorably to selection and that CC is moderately repeatable.


2018 ◽  
Vol 63 (No. 6) ◽  
pp. 212-221 ◽  
Author(s):  
B.B. Teixeira ◽  
R.R. Mota ◽  
R.B. Lôbo ◽  
L.P. Silva ◽  
A.P. Souza Carneiro ◽  
...  

We aimed to evaluate different orders of fixed and random effects in random regression models (RRM) based on Legendre orthogonal polynomials as well as to verify the feasibility of these models to describe growth curves in Nellore cattle. The proposed RRM were also compared to multi-trait models (MTM). Variance components and genetic parameters estimates were performed via REML for all models. Twelve RRM were compared through Akaike (AIC) and Bayesian (BIC) information criteria. The model of order three for the fixed curve and four for all random effects (direct genetic, maternal genetic, permanent environment, and maternal permanent environment) fits best. Estimates of direct genetic, maternal genetic, maternal permanent environment, permanent environment, phenotypic and residual variances were similar between MTM and RRM. Heritability estimates were higher via RRM. We presented perspectives for the use of RRM for genetic evaluation of growth traits in Brazilian Nellore cattle. In general, moderate heritability estimates were obtained for the majority of studied traits when using RRM. Additionally, the precision of these estimates was higher when using RRM instead of MTM. However, concerns about the variance components estimates in advanced ages via Legendre polynomial must be taken into account in future studies.


Author(s):  
Getenet Dessie ◽  
Henok Mulugeta ◽  
Desalegne Amare ◽  
Ayenew Negesse ◽  
Fasil Wagnew ◽  
...  

Abstract Background Despite the high prevalence of diabetes in Africa, the extent of undiagnosed diabetes in the region is still poorly understood. This systematic review and meta-analysis was designed to determine the pooled prevalence of undiagnosed diabetes mellitus among adults in Africa. Methods We conducted a systematic desk review and electronic web-based search of PubMed, Google Scholar, EMBASE, and the World Health Organization’s Hinari portal (which includes the SCOPUS, African Index Medicus, and African Journals Online databases), identifying peer-reviewed research studies on the prevalence of undiagnosed diabetes among adult individuals using pre-defined quality and inclusion criteria. We ran our search from June 1, 2018 to Jun 14, 2020. We extracted relevant data and presented descriptive summaries of the studies in tabular form. The I2 test was used to assess heterogeneity across studies. A random effects model was used to estimate the pooled prevalence of undiagnosed diabetes mellitus at a 95% confidence interval (CI). Funnel plot asymmetry and Egger’s tests were used to check for publication bias. The final effect size was determined by applying a trim and fill analysis in a random-effects model. Results Our search identified 1442 studies amongst which 23 articles were eligible for inclusion in the final meta-analysis. The average pooled prevalence of undiagnosed diabetes mellitus among adults was 3.85 (95% CI: 3.10–4.60). The pooled prevalence of undiagnosed diabetes mellitus based on geographic location was 4.43 (95% CI: 3.12–5.74) in Eastern Africa; 4.72 (95% CI: 2.64–6.80) in Western Africa; 4.27 (95% CI: 1.77–6.76) in Northern Africa and 1.46 (95%CI: 0.57–2.34) in southern Africa respectively. Conclusion Our findings indicate a high prevalence of undiagnosed diabetes in Africa and suggest that it may be more prevalent in Western Africa than the rest of the regions. Given the high levels of undiagnosed diabetes in the Africa region, more attention should be paid to incorporating diabetes screening and treatment services into existing diabetes related programs to reduce the prevalence of undiagnosed cases.


2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Dawood Aghamohammadi ◽  
Neda Dolatkhah ◽  
Fahimeh Bakhtiari ◽  
Fariba Eslamian ◽  
Maryam Hashemian

AbstractThis study designed to evaluate the effect of nutraceutical supplementation on pain intensity and physical function in patients with knee/hip OA. The MEDLINE, Web of Science, Cochrane Library, Scopus, EMBASE, Google Scholar, Science direct, and ProQuest in addition to SID, Magiran, and Iranmedex were searched up to March 2020. Records (n = 465) were screened via the PICOS criteria: participants were patients with hip or knee OA; intervention was different nutritional supplements; comparator was any comparator; the outcome was pain intensity (Visual analogue scale [VAS]) and physical function (Western Ontario and McMaster Universities Arthritis [WOMAC] index); study type was randomized controlled trials. The random effects model was used to pool the calculated effect sizes. The standardized mean difference (SMD) of the outcome changes was considered as the effect size. The random effects model was used to combine the effect sizes. Heterogeneity between studies was assessed by Cochran's (Q) and I2 statistics. A total of 42 RCTs were involved in the meta-analysis. Nutritional supplementation were found to improve total WOMAC index (SMD = − 0.23, 95% CI − 0.37 to − 0.08), WOMAC pain (SMD = − 0.36, 95% CI − 0.62 to − 0.10) and WOMAC stiffness (SMD = − 0.47, 95% CI − 0.71 to − 0.23) subscales and VAS (SMD = − 0.79, 95% CI − 1.05 to − 0.05). Results of subgroup analysis according to the supplementation duration showed that the pooled effect size in studies with < 10 months, 10–20 months and > 20 months supplementation duration were 0.05, 0.27, and 0.36, respectively for WOMAC total score, 0.14, 0.55 and 0.05, respectively for WOAMC pain subscale, 0.59, 0.47 and 0.41, respectively for WOMAC stiffness subscale, 0.05, 0.57 and 0.53, respectively for WOMAC physical function subscale and 0.65, 0.99 and 0.12, respectively for VAS pain. The result suggested that nutraceutical supplementation of patients with knee/hip OA may lead to an improvement in pain intensity and physical function.


2020 ◽  
pp. 019459982095117
Author(s):  
Craig A. Bollig ◽  
David S. Lee ◽  
Angela L. Mazul ◽  
Katelyn Stepan ◽  
Sidharth V. Puram ◽  
...  

Objective To systematically review the literature to determine the prevalence and clinical outcomes of second primary oropharyngeal squamous cell carcinoma (OPSCC). Data Sources Search strategies created with a medical librarian were implemented using multiple databases in October 2019. Review Methods The population of interest included adults age >18 years with a p16+ or human papillomavirus-positive OPSCC. The outcome was a synchronous or metachronous second primary OPSCC. Inclusion and exclusion criteria were designed to capture all study designs. In total, 685 records were identified by the search strategy. Two reviewers independently performed the review, extracted data, and performed a quality assessment. Primary Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines were followed. A random-effects model was used for the meta-analysis. Results A total of 2470 patients with 35 second primary OPSCCs from 15 studies were identified. The pooled prevalence of second primary OPSCC was 1.4% (range, 0%-14.3%). In the random-effects model, the prevalence was estimated at 1.3% (95% CI, 0.7%-2.3%; P = .51, I2 = 52%). Of the 30 patients with treatment information, 26 (86.7%) received surgical treatment, while 4 (13.3%) underwent nonsurgical therapy. Of the 29 patients with available survival information, 22 (75.9%) had no evidence of disease at last follow-up, 5 (17.2%) ultimately died of disease, and 2 (6.9%) were alive with disease. Conclusion Overall, the rate of second primary OPSCC in patients with an index p16+ OPSCC is low, and most patients are successfully treated. Insufficient evidence currently exists to recommend routine elective tonsillectomy during surgical treatment of p16+ OPSCC.


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