Genetic Sources of Variation in the Gestation Length of the Horse

1951 ◽  
Vol 10 (4) ◽  
pp. 797-806 ◽  
Author(s):  
W. C. Rollins ◽  
C. E. Howell
1951 ◽  
Vol 10 (4) ◽  
pp. 789-796 ◽  
Author(s):  
C. E. Howell ◽  
W. C. Rollins

2014 ◽  
Vol 8 ◽  
pp. 77-81
Author(s):  
Shreeram P. Neopane

Pakhribas pig is a black colour pig and is highly preferred by the people in the Eastern hills of Nepal. This breed was developed in Nepal by three-way crossing of exotic breeds  (Saddle back, Fayuen and Tamworth) at Agricultural Research Station (ARS), Pakhribas, the then Pakhribas Agricultural Centre (PAC). The data of 348 pigs, born over a period of fifteen years (1990 to 2004) were used to study the effect of non-genetic factors on reproductive traits and estimate their genetic parameters. The findings revealed that the   overall gestation length and farrowing intervals were 113.7 ± 0.12 days and 182.5 ± 2.2 days, respectively. Season of birth and parity of dams were not important sources of variation for reproductive traits, where as year affected these traits significantly. Heritability estimates of gestation length was low (0.02 ± 0.094), but heritability for farrowing interval was moderate (0.14 ± 0.147) suggesting selection based on farrowing interval would bring the improvement in the trait.Nepal Agric. Res. J. Vol. 8, 2007, pp. 77-81DOI: http://dx.doi.org/10.3126/narj.v8i0.11584


2018 ◽  
Author(s):  
Charlotte A. Hudson ◽  
Liam Satchell ◽  
Nicole M Adams-Quackenbush

Purpose: Investigative interviews are complex, dyadic, activities typically studied by focusing on developing techniques to improve witness performance. However, in field settings, interviewers are known to vary in their presentation of good interviewing practice. Thus, it is important to conduct research reflective of complex idiosyncrasies in witnesses, interviewers and unique pairings of both. This study explores such sources of variation in an by making use of a 'round-robin' design. Such methodology allows the statistical demonstration of individual difference and unique partner-generated variance in interview performance. Methods: In our study, a total of 45 witnesses were questioned about five real crime videos. After witnessing each event, witnesses were interviewed by a different interviewer (or a computer self-administered interview). In total, nine 'rounds' of interviews occurred, with five new witnesses being interviewed in the same five interview settings (resulting in 225 interviews). After each interview both interviewers and witnesses were asked to complete subjective interview experience ratings. The quality (grain size) and quantity of information in the statements was coded to index witness report accuracy. Results: Principally, the results demonstrate the degree to which witnesses and interviewers affect statement quality, and highlight the influence of unique interviewer-witness pairs. (Participant personality and interviewer behaviour were also analysed, but with limited effects). Conclusion: This study presents the useful round-robin methodology for studying interviewer-witness behaviour. Whilst the current personality and behavioural measures do not account for these individual differences, we advocate this methodology be adopted more widely to better understand interview performance.


Author(s):  
Elin Haugsgjerd Allern ◽  
Tània Verge

How parties structure their interaction with social groups is a key determinant of their capacity to provide linkage between the institutions of government and the public at large. This chapter investigates the extent to which modern political parties use formal measures to connect to relevant societal interests and strengthen their anchorage in society. The analysis centres on parties’ use of formal rules governing affiliation and representation to link with externally organized interests and parties’ establishment of sub-organizations with representation rights within the party. The chapter authors develop and test several hypotheses concerning cross-country and within-country sources of variation in formal linkage and test them empirically. In addition, they examine whether formal status and representation rights shape parties’ ability to represent descriptively the associated latent social interests focusing on the case of women and ethnic minorities.


Author(s):  
Gustav Hultgren ◽  
Mansoor Khurshid ◽  
Peter Haglund ◽  
Zuheir Barsoum

AbstractA round-robin study has been carried out within a national project in Sweden with the addition of an international participant, where several industrial partners and universities are participating. The project aims to identify variation and sources of variation in welding production, map scatter in fatigue life estimation, and define and develop concepts to reduce these, in all steps of product development. The participating organisations were asked to carry out fatigue life assessment of welded box structures, which is a component in load-carrying structures. The estimations of fatigue life have also been compared with fatigue test results. Detailed drawings, loads and material data were also given to the participants. The participants were supposed to use assessment methods based on global and local stresses using the design codes or recommendations they currently use in-house. Differences were identified between both methods and participants using the same codes/recommendations. Applicability and conditions from the cases in the codes were also identified to be differently evaluated between the participants. It could be concluded that for the applied cases the nominal stress method often overestimated the fatigue life and had a high scatter in the estimations by different participants. The effective notch method is conservative in comparison to the life of tested components with little scatter between the results derived by the participants.


Author(s):  
Carola Borries ◽  
Jeroen B. Smaers ◽  
Carrie S. Mongle ◽  
Andreas Koenig

Author(s):  
Jarrad Gollihue ◽  
Victoria G. Pook ◽  
Seth DeBolt
Keyword(s):  

2020 ◽  
Vol 58 (8) ◽  
pp. 1302-1313 ◽  
Author(s):  
Anwar Borai ◽  
Kiyoshi Ichihara ◽  
Abdulaziz Masaud ◽  
Waleed Tamimi ◽  
Suhad Bahijri ◽  
...  

AbstractBackgroundThis is a second part of report on the IFCC global multicenter study conducted in Saudi Arabia to derive reference intervals (RIs) for 20 immunoassay analytes including five tumor makers, five reproductive, seven other hormones and three vitamins.MethodsA total of 826 apparently healthy individuals aged ≥18 years were recruited in three clinical laboratories located in western, central and eastern Saudi Arabia using the protocol specified for the global study. All serum specimens were measured using Abbott, Architect analyzers. Multiple regression analysis (MRA) was performed to explore sources of variation of each analyte: age, body mass index (BMI), physical exercise and smoking. The magnitude of variation of reference values (RVs) attributable to sex, age and region was calculated by ANOVA as a standard deviation ratio (SDR). RIs were derived by the parametric (P) method.ResultsMRA revealed that region, smoking and exercise were not relevant sources of variation for any analyte. Based on SDR and actual between-sex differences in upper limits (ULs), we chose to partition RIs by sex for all analytes except for α-fetoprotein and parathyroid hormone (PTH). Age-specific RIs were required in females for ferritin, estradiol, progesterone, testosterone, follitropin, luteotropin and prolactin (PRL). With prominent BMI-related increase, RIs for insulin and C-peptide were derived after excluding individuals with BMI > 32 kg/m2. Individuals taking vitamin D supplements were excluded in deriving RIs for vitamin D and PTH.ConclusionsRIs of major immunoassay analytes specific for Saudi Arabians were established in careful consideration of various biological sources of variation.


Author(s):  
N Fetherstone ◽  
N McHugh ◽  
T M Boland ◽  
F M McGovern

Abstract The objective of this study was to investigate the impact of the ewe’s maternal genetic merit and country of origin (New Zealand or Ireland) on ewe reproductive, lambing and productivity traits. The study was performed over a four year period (2016 to 2019) and consisted of three genetic groups: high maternal genetic merit New Zealand (NZ), high maternal genetic merit Irish (High Irish) and low maternal genetic merit Irish (Low Irish) ewes. Each group contained 30 Suffolk and 30 Texel ewes, selected based on the respective national maternal genetic indexes; i.e. either the New Zealand Maternal Worth (New Zealand group) or the €uro-star Replacement index (Irish groups). The impact of maternal genetic merit on reproductive traits such as litter size; lambing traits such as gestation length, birth weight, lambing difficulty, mothering ability, and productivity traits such as the number of lambs born and weaned were analyzed using linear mixed models. For binary traits, the impact of maternal genetic merit on reproductive traits such as conception to first AI service; lambing traits such as dystocia, perinatal lamb mortality and productivity traits such as ewe survival were analyzed using logistic regression. New Zealand ewes outperformed Low Irish ewes for conception to first AI (P<0.05) and litter size (P=0.05). Irish ewes were more likely to suffer from dystocia (6.84 (High Irish) and 8.25 (Low Irish) times) compared to NZ ewes (P<0.001); birth weight and perinatal mortality did not differ between groups (P>0.05). Lambs born from NZ ewes were 4.67 (95% CI: 1.89 to 11.55; P<0.001) and 6.54 (95% CI: 2.56 to 16.71; P<0.001) times more likely to stand up and suckle unassisted relative to lambs born from High or Low Irish ewes, respectively. New Zealand and High Irish ewes had a greater number of lambs born and weaned throughout the duration of the study compared to their Low Irish counterparts (P<0.001). New Zealand ewes tended to be more likely to survive from one year to the next compared to Low Irish ewes (P=0.07). Irish ewes of high maternal genetic merit outperformed their Low counterparts in total number of lambs born and weaned per ewe, but performance did not differ across other traits investigated. This highlights the importance of continuous development of the Irish maternal sheep index to ensure favourable improvements in reproductive, lambing and productivity traits at farm level. Overall, results demonstrate the suitability of NZ genetics in an Irish production system.


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