scholarly journals Meta Analiz Yaklaşımı ile Laktasyon Sırası ve Buzağılama Mevsiminin 305 Günlük Laktasyon Süt Verimi Üzerindeki Etki Büyüklüğünün Tahmini

2014 ◽  
Vol 3 (1) ◽  
pp. 17
Author(s):  
Hande Küçükönder ◽  
Fatih Üçkardeş ◽  
Ercan Efe
Keyword(s):  
Milk Yield ◽  
Odds Ratio ◽  
Meta Analysis ◽  
Screening Method ◽  
Fixed Effect Model ◽  
Statistical Technique ◽  
Chi Square ◽  
Common View ◽  
Holstein Friesian ◽  
Calving Season

In this study, the effect of the lactation sequence and the calving season, which are one of the factors influencing the milk yield in Holstein Friesian breed cows, were studied with meta-analysis method. Meta-analysis is a statistical technique that allows a re-evaluation of the studies conducted by other researchers for the same purpose by bringing them together. Meta-analysis combines and summarizes the results of the studies conducted on various fields, and contributes in making a common judgment among researchers. For these reasons, the studies of 7 different researchers that have been made in this field were brought together and it was aimed to create a common view about the studied parameters. In addition, the heterogeneity in this study was investigated by Chi-Square and I2 test statistics, and these values were found as ×^2=50.205 and I2= 88%, respectively. Therefore, for combining the studies, the fixed effect model wasn’t used in meta-analysis. In this study, the results of the researchers’ studies’ regarding the subject in question were scanned with meta-analytical screening method, and were combined by using the odds ratio (OR) which is the effect size criterion in meta-analysis. As a result of the meta-analysis, the Odds ratio value was found as 0.759 and the effect level was determined middle. With this study conducted, as a result of this meta-analysis conducted, it was found that the contribution done by the lactation sequence on 305-day lactation milk yield in Holstein Friesian cattles in obtaining high milk yield was 0.759 times more compared to the calving season.

An attempt to develop a method for determining the typical chemical composition of the milk of Polish Holstein-Friesian cows – a proposal

2019 ◽  
Vol 15 (3) ◽  
pp. 9-21
Author(s):  
Piotr Guliński ◽  
Anna Kłopotowska
Keyword(s):  
Chemical Composition ◽  
Somatic Cell ◽  
Cell Count ◽  
Milk Yield ◽  
Somatic Cell Count ◽  
Scientific Publications ◽  
Lactation Stage ◽  
Holstein Friesian ◽  
Calving Season ◽  
The Impact

The aim of this paper is to develop a method for determining the typical chemical composition of the milk of Polish Holstein-Friesian (PHF) cows. The paper uses data collected from 1329 test-day milking records from 20 herds of PHF dairy cattle in Sokołów County, from 2009 to 2015. The effect of the following factors on the chemical composition of milk was determined: lactation stage (15 one-month stages); age of cows (lactations 1, 2, 3–4, and 5–7); genotype (share of PHF breed: less than 50%, 50–75%, 75–82.5% and more than 82.5%); somatic cell count (SCC) in 1 ml of milk (in thousands: 0–200, 200–400, 400–1000 and more than 1000); feeding level (fat to protein (F/P) ratio): ≤1.0, 1.0–1.4, 1.4–1.7 and >1.7); calving season (autumn/winter, spring/summer) and daily milk yield (milk yield in kg: ≤15, 15–25, 25–35 and >35). Nutrition and udder health status were found to be the main factors influencing the chemical composition of milk. For selected cows with optimally balanced feed rations (F/P ratio in milk from 1.1 to 1.4) and a low somatic cell count (SCC ≤200,000/ml), daily yield was the main factor affecting the chemical composition of the milk. It was also concluded that government and scientific publications on the PHF breed should take into account the impact of the F/P ratio, SCC and yield of milk on its composition.

Effect of age at first calving and other non-genetic factors on longevity and production traits in Holstein cattle under Vojvodina Province condition, Serbia

2019 ◽  
Author(s):  
D. Kuèeviæ ◽  
S. Dragin ◽  
I. Pihler ◽  
K. Èobanoviæ ◽  
T. Papoviæ ◽  
...  
Keyword(s):  
Milk Yield ◽  
Genetic Factors ◽  
Fixed Effect Model ◽  
Production Traits ◽  
Age At First Calving ◽  
Effect Model ◽  
Calving Season ◽  
Novi Sad ◽  
Effect Of Age ◽  
Vojvodina Province

The effect of age at first calving (AFC) and various non-genetic factors i.e. season of calving, farm and system of housing on longevity and production traits were investigated. Longevity traits were studied using total lifetime (TL), length of productive life (LPL) and number of lactations (NL) while production was researched using lifetime milk yield (LMY). Data of 2037 Holstein dairy cows were provided by the main breeding organizations at the Faculty of Agriculture, University of Novi Sad. The average values and variability of examined traits as well as the effect of factors on longevity and production traits were investigated using fixed effect model by general linear model (GLM) procedure in software package Statistica 13. Results showed highly significant effect of the AFC, calving season and farm, on all studied longevity traits (P less than 0.01), while non- significant effect was expressed on lifetime milk yield (P greater than 0.05). The mean of AFC, TL, LPL, NL and LMY for Holstein cows were 27.3, 67.5, 40.2 months, 2.45 and 18798.0 kg, respectively. The maximum values of LPL, NL and LMY were noticed for cows with age at first calving before 23 months of age. The LPL ranged from 47.88 (AFC less than 23 m) to 35.84 m (AFC>29 m) and declined progressively when the AFC is increased, particularly in cows calving at more than 29 m.

scholarly journals Genetic and non genetic effects for lactation curve traits in Holstein-Friesian cows

2012 ◽  
Vol 55 (5) ◽  
pp. 450-457 ◽  
Author(s):  
I. Boujenane ◽  
B. Hilal
Keyword(s):  
Milk Yield ◽  
Genetic Correlations ◽  
Genetic Effects ◽  
Peak Time ◽  
Holstein Friesian ◽  
Lactation Curve ◽  
Genetic And Phenotypic Correlations ◽  
Selection For ◽  
Calving Season ◽  
Friesian Cows

Abstract. The objective of this study was to determine the genetic and non genetic effects on lactation curve traits determined by the incomplete gamma function of Wood (1967) for Holstein-Friesian cows in Morocco. Data analysed included 49262 monthly records of the test-day milk yield from 4888 lactations of 3932 cows at their 1st, 2nd or 3rd parity collected during 1990 and 1999 in 232 herds enrolled in the official milk recording. In general, lactation curve traits (A, B, C, peak time [Tmax], peak milk yield [Ymax], persistency and 305 day milk yield [MY305]) were affected by herd, parity, age at calving, season of calving and year of calving. Heritability estimates were low and varied from 0.01 for parameter A to 0.10 for Ymax. Genetic and phenotypic correlations among traits varied from −0.79 to 1.00 and from −0.80 to 0.96, respectively. Genetic correlations between MY305 and parameter C were negative, but those between MY305 and all the other lactation curve traits were positive. It was concluded that selection for high peak milk yield and persistency will result in higher 305 day milk yield.

scholarly journals Greater Incidence of Emergence Agitation in Children after Sevoflurane Anesthesia as Compared with Halothane

2008 ◽  
Vol 109 (2) ◽  
pp. 225-232 ◽  
Author(s):  
Norifumi Kuratani ◽  
Yumiko Oi
Keyword(s):  
Confidence Interval ◽  
Publication Bias ◽  
Odds Ratio ◽  
Pain Treatment ◽  
Meta Analysis ◽  
Fixed Effect Model ◽  
Sevoflurane Anesthesia ◽  
Emergence Agitation ◽  
Inclusion Criteria ◽  
Halothane Anesthesia

Background Sevoflurane is a popular inhalational anesthetic for general anesthesia in children. The higher incidence of emergence agitation has been suspected after sevoflurane anesthesia as compared with halothane, whereas some controlled studies showed conflicting results. In this report, the authors performed a meta-analysis of randomized controlled trials to compare the incidence of emergence agitation in children after sevoflurane or halothane anesthesia. Methods A comprehensive literature search was conducted to identify clinical trials that compared the incidence of emergence agitation in children anesthetized with sevoflurane versus halothane. Two reviewers independently assessed each report to meet the authors inclusion criteria and extracted data. The data from each trial were combined using the Mantel-Haenszel fixed-effect model to calculate the pooled odds ratio and 95% confidence interval. Funnel plots were used to assess publication bias. Subgroup analysis was used to clarify the effects of age, surgical procedure, pain treatment, and premedication on the incidence of emergence agitation. Results The authors identified 23 studies that met their inclusion criteria. Overall, 1,252 patients received sevoflurane and 1,111 had halothane. Heterogeneity of data was statistically refuted. The pooled odds ratio for all studies was 2.21, with a 95% confidence interval of 1.77-2.77 (P < 0.0001). Publication bias was not apparent in a funnel plot. All subgroup analyses showed a higher incidence of agitation after sevoflurane anesthesia. Conclusions This meta-analysis revealed that emergence agitation occurred more frequently with sevoflurane than with halothane anesthesia in children.

scholarly journals Aspirin and death in Covid-19 A systematic review and meta-analysis

2021 ◽  
Author(s):  
Nicholas Moore (NO NEW ASSIGNMENTS) ◽  
Nicolas Thurin ◽  
Pauline Bosco-Lévy ◽  
Patrick Blin ◽  
cecile Droz
Keyword(s):  
Systematic Review ◽  
Random Effects ◽  
Odds Ratio ◽  
Data Extraction ◽  
Meta Analysis ◽  
Cochrane Collaboration ◽  
Fixed Effect Model ◽  
Random Effects Model ◽  
Risk Of Death ◽  
Relative Risks

Thrombotic events are common during COVID-19 infection. Aspirin might be beneficial. Objective: Systematic review and meta-analysis of deaths in users and non-users of aspirin. Data sources: Pubmed Medline, Google scholar, Clinicaltrials.gov, Cochrane, to June 8, 2021, Study selection: Studies providing adjusted or matched evaluation of association of exposure to aspirin and death in COVID-19 patients were included. Data extraction and synthesis: Data were used as published, as Odds ratio, hazard ratio or relative risks and 95% CI from which log(OR) and SE were recalculated. These were entered in an inverse variance odds ratios random-effects model, using RevMan 5.4 (the Cochrane Collaboration). Main outcomes and measure: The prespecified outcome studied was death. Results: Nine studies (8 observational, one interventional) included 14989 patients exposed to aspirin and 15857 unexposed. Overall Odds Ratio of death in aspirin exposed patients in a random effects model was 0.63, 95% confidence interval [0.40-0.99], I2 94%. Using a fixed-effect model did not change much the result (0.76 [0.71-0.81], removing the Recovery trial (OR 0.43 [0.38-0.49], I271%, or the two largest studies (0.66 [0.47-0.93], I2 38%) reduced heterogeneity without materially altering the results. The funnel plot showed no evident publication bias Conclusion: this meta-analysis suggests that the use of aspirin may be associated with a lower risk of death in COVID-19. Considering the results of the Recovery Study, it would appear preferable to continue aspirin in patients who have a non-covid indication, but possibly useless to add it if they don’t.

scholarly journals A Systematic Review and Meta-analysis of the Protective Effect of FMDV VP1 on Animals

2020 ◽  
Author(s):  
Peng Wu ◽  
Qingqing Liu ◽  
Jinke He ◽  
Xiaoyu Deng ◽  
Xinyue Yin ◽  
...  
Keyword(s):  
Sensitivity Analysis ◽  
Protective Effect ◽  
Publication Bias ◽  
Meta Analysis ◽  
Experimental Studies ◽  
Fixed Effect Model ◽  
Chi Square ◽  
Protection Effect ◽  
Vp1 Protein ◽  
Effect Model

AbstractThe FMDV VP1 protein has different structures which could decrease or increase the immune response. We undertook a meta-analysis to evaluate the protective effect of VP1 on the FMDV. A systematic search of the PubMed, Embase, CNKI and Wan fang DATA was conducted up to April 2020. Experimental studies involving the VP1 protection effect on FMDV were included. Extracted data were analyzed using Rev-Man 5.3 software. Chi-square tests were used to analyze the heterogeneity among the documents. The fixed-effect model was used for meta-analysis to find the combined effect value and 95% confidence interval. Sensitivity analysis was performed on the differences in the combined values of model effects, and the inverted funnel chart method was used to assess the publication bias of the included literature. A total of 12 articles were included for meta-analysis. The results of showed that VP1 had a protective effect on FMDV [MH = -0.66, 95% CI = (−0.75, -0.56), P < 0.00001]. Sensitivity analysis showed that the results were robust. The funnel graph method showed that the published literature had a small publication bias and met the requirements of this study. It is necessary to study the epitopes of VP1 to produce new vaccines. VP1 could protect animals from FMDV attacks. It is necessary to study the VP1 protein and its epitopes and use it as a new vaccine and diagnostic product.

Association between Overweight and Hypertension in Adolescents: A Meta-Analysis

2020 ◽  
Author(s):  
Fadhila Firmanurulita ◽  
◽  
Agus Kristiyanto ◽  
Hanung Prasetya ◽  
◽  
...  
Keyword(s):  
Odds Ratio ◽  
English Language ◽  
Meta Analysis ◽  
Fixed Effect Model ◽  
Overweight And Obesity ◽  
Reporting Odds Ratio ◽  
Cross Sectional ◽  
Obesity Epidemic ◽  
Central Java ◽  
Adolescent Overweight

Background: The upward trend in adolescent hypertension is widely attributed to the adolescent overweight and obesity epidemic. Because of their high-risk status, intervention in overweight adolescents with associated comorbidities, such as hypertension, should be considered. The purpose of this study was to examine association between overweight and hypertension in adolescents. Subjects and Method: This was a meta-analysis and systematic review. The articles were obtained from PubMed, Springer Link, and Google Scholar databases, which published from 2006 to 2020. Keywords used “hypertension” AND “adolescents” AND” obesity” AND “risk factor of obesity” AND “cross-sectional” AND “adjusted odds ratio”. The inclusion criteria were full-text, using English language, and reporting Odds ratio. The study population was adolescents. The intervention was overweight with comparison non overweight. The study outcome was hypertension. The articles were reviewed by PRISMA diagram and analyzed by RevMan 5.3. Results: 8 articles from Ethiopia, Spanyol, Canada, Taiwan, Lithuania, United States, and Malaysia were met criteria. The data analysis found low heterogeneity between groups (I2= 40%; p=0.110), so it used fixed effect model. This meta-analysis study reported that overweight increases the risk of hypertension in adolescents (aOR= 3.32; 95% CI= 3.02 to 3.66; p<0.001). Conclusion: Overweight increases the risk of hypertension in adolescents. Keywords: overweight, hypertension, adolescents Correspondence: Fadhila Firmanurulita. Masters Program in Public Health, Universitas Sebelas Maret. Jl. Ir. Sutami 36A, Surakarta 57126, Central Java. Email: [email protected]. Mobile: 085740045026.

A Method for Meta-Analysis of Epidemiological Studies

1988 ◽  
Vol 22 (10) ◽  
pp. 813-824 ◽  
Author(s):  
Thomas R. Einarson ◽  
J. Steven Leeder ◽  
Gideon Koren
Keyword(s):  
Confidence Interval ◽  
Odds Ratio ◽  
Meta Analysis ◽  
A Priori ◽  
Epidemiological Studies ◽  
Percent Confidence Interval ◽  
Case Control Studies ◽  
Chi Square ◽  
The Impact ◽  
Summary Odds Ratio

This article presents a stepwise approach for conducting a meta-analysis of epidemiological studies based on proposed guidelines. This systematic method is recommended for practitioners evaluating epidemiological studies in the literature to arrive at an overall quantitative estimate of the impact of a treatment. Bendectin is used as an illustrative example. Meta-analysts should establish a priori the purpose of the analysis and a complete protocol. This protocol should be adhered to, and all steps performed should be recorded in detail. To aid in developing such a protocol, we present methods the researcher can use to perform each of 22 steps in six major areas. The illustrative meta-analysis confirmed previous traditional narrative literature reviews that Bendectin is not related to teratogenic outcomes in humans. The overall summary odds ratio was 1.01 (χ2 = 0.05, p = 0.815) with a 95 percent confidence interval of 0.66–1.55. When the studies were separated according to study type, the summary odds ratio for cohort studies was 0.95 with a 95 percent confidence interval of 0.62–1.45. For case-control studies, the summary odds ratio was 1.27 with a 95 percent confidence interval of 0.83–1.94. The corresponding chi-square values were not statistically significant at the p = 0.05 level.

scholarly journals A Meta-Analysis for Association of Maternal Smoking with Childhood Refractive Error and Amblyopia

2016 ◽  
Vol 2016 ◽  
pp. 1-7 ◽  
Author(s):  
Li Li ◽  
Ya Qi ◽  
Wei Shi ◽  
Yuan Wang ◽  
Wen Liu ◽  
...  
Keyword(s):  
Risk Factor ◽  
Confidence Interval ◽  
Publication Bias ◽  
Refractive Error ◽  
Odds Ratio ◽  
Maternal Smoking ◽  
Meta Analysis ◽  
Significant Heterogeneity ◽  
Chi Square ◽  
The Difference

Background. We aimed to evaluate the association between maternal smoking and the occurrence of childhood refractive error and amblyopia.Methods. Relevant articles were identified from PubMed and EMBASE up to May 2015. Combined odds ratio (OR) corresponding with its 95% confidence interval (CI) was calculated to evaluate the influence of maternal smoking on childhood refractive error and amblyopia. The heterogeneity was evaluated with the Chi-square-basedQstatistic and theI2test. Potential publication bias was finally examined by Egger’s test.Results. A total of 9 articles were included in this meta-analysis. The pooled OR showed that there was no significant association between maternal smoking and childhood refractive error. However, children whose mother smoked during pregnancy were 1.47 (95% CI: 1.12–1.93) times and 1.43 (95% CI: 1.23-1.66) times more likely to suffer from amblyopia and hyperopia, respectively, compared with children whose mother did not smoke, and the difference was significant. Significant heterogeneity was only found among studies involving the influence of maternal smoking on children’s refractive error (P<0.05;I2=69.9%). No potential publication bias was detected by Egger’s test.Conclusion. The meta-analysis suggests that maternal smoking is a risk factor for childhood hyperopia and amblyopia.

scholarly journals Survival of Polish Holstein-Friesian cows to second, third and fourth lactation in conventional and automatic milking systems

2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Dariusz Piwczyński ◽  
Beata Sitkowska ◽  
Marcin Brzozowski ◽  
Mariusz Bogucki ◽  
Piotr Wójcik
Keyword(s):  
Logistic Regression ◽  
Milk Yield ◽  
Low Fertility ◽  
Holstein Friesian ◽  
Chance Events ◽  
Automatic Milking ◽  
Calving Season ◽  
Automatic Milking Systems ◽  
Positive Effect ◽  
Friesian Cows

Abstract The main objective of the study was to determine the effect of transition from a conventional milking system (CMS) to an automatic milking system (AMS) on survival of 6361 Polish Holstein-Friesian cows to second (SL2), third (SL3) and fourth (SL4) lactation as well culling reasons. The cows were born between 2002 and 2015 and calved between 2004 and 2018. All data for the survival analysis and culling reasons of cows in 17 herds during operation of CMS and AMS were extracted from the SYMLEK official milk recording system. Cow survival (SL2, SL3 and SL4) was analysed with multiple logistic regression using the following effects in the model: milking system (MS), first calving season (CS), age at first calving (AFC), ease of first calving (CE), birth of a dead calf at first calving (DC), milk yield (MY) for full first lactation (MY – this effect was ignored in SL2 analysis), herd (H), and MS × H interaction. In the next stage of the study, χ2 test was used to analyse culling reasons of cows (udder diseases, low fertility (infertility and reproductive disorders), locomotor diseases, low milk yield, other diseases (metabolic, digestive and respiratory diseases), accidents and chance events) in the first, second and third lactation and collectively in the first three lactations. Logistic regression analysis indicated a significant effect of MS, AFC, DC on SL2 and SL3, and of MY on SL3 and SL4. Moreover, H and MS × H interaction had a highly significant effect on SL2, SL3, and SL4. Cows used in AMS barns were characterized by significantly worse SL2 and SL3 compared to CMS (odds ratio), by 27.8% and 31.0%, respectively. It was also observed that the effect of switching from CMS to AMS on cow survival was determined by herd membership – in most herds this effect was unfavourable. A distinctly positive effect of milking automation on cow survival (SL2, SL3, SL4) was noted in only one barn (herd) – it was a new barn with a considerably expanded number of milked cows, where the lying area was covered with straw. When analysing the reasons for culling in the first three lactations collectively, it was found that after the AMS system was introduced into the herds, there were increases in the rate of culling for locomotor diseases (by 0.85 percentage points (p.p.)), low milk yield (1.36 p.p.) and other diseases (3.01 p.p.). It was also observed that the automation of milking reduced culling due to udder diseases by 0.37 p.p., low fertility by 3.24 p.p., and accidents and chance events by 1.60 p.p.

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