scholarly journals The efficiency of multi-generation selection on maternal traits, with implications for reindeer

2020 ◽  
Vol 29 (5) ◽  
Author(s):  
Jaakko Pietarinen ◽  
Asko Mäki-Tanila
Keyword(s):  
Negative Correlation ◽  
Variance Component ◽  
Economic Value ◽  
Maternal Response ◽  
Mammal Species ◽  
Growth And Survival ◽  
Economic Weights ◽  
Component Approach ◽  
Estimated Breeding Values ◽  
Variance Component Approach

Maternally affected traits, such as juvenile growth and survival, provide resilience in mammal species, in particular for reindeer living in extreme northern habitat. The genetic variation in such traits is caused by direct and maternal genetic effects (DGE and MGE, respectively). We used Willham’s variance-component approach and extended a family index with the focal individual and its full- and half-sibs to an approximated BLUP (pseudo-BLUP) by including the parents’ estimated breeding values. Most of the deviations of the predicted responses from the simulated ones were 4.1% for DGE and 5.3% for MGE. The benefits of index and BLUP selection are high in the case of negative correlation, large full-sib family and in particular, when maternal half-sibs are available. Higher economic value for MGE than for DGE is needed, since with equal heritabilities and economic weights for the effects the maternal response is 40 to 70% of the direct one. With negative correlation, records on collateral relatives beyond sibs are possibly needed. They would support also the prediction of MGE in uniparous reindeer lacking full-sib information.

Mapping Quantitative Trait Loci in Complex Pedigrees: A Two-Step Variance Component Approach

Genetics ◽  
2000 ◽  
Vol 156 (4) ◽  
pp. 2081-2092 ◽  
Author(s):  
Andrew W George ◽  
Peter M Visscher ◽  
Chris S Haley
Keyword(s):  
Quantitative Trait Loci ◽  
Quantitative Trait ◽  
Variance Component ◽  
Simulated Data ◽  
Statistical Techniques ◽  
Animal Populations ◽  
Trait Loci ◽  
Component Approach ◽  
Complex Relationships ◽  
Variance Component Approach

Abstract There is a growing need for the development of statistical techniques capable of mapping quantitative trait loci (QTL) in general outbred animal populations. Presently used variance component methods, which correctly account for the complex relationships that may exist between individuals, are challenged by the difficulties incurred through unknown marker genotypes, inbred individuals, partially or unknown marker phases, and multigenerational data. In this article, a two-step variance component approach that enables practitioners to routinely map QTL in populations with the aforementioned difficulties is explored. The performance of the QTL mapping methodology is assessed via its application to simulated data. The capacity of the technique to accurately estimate parameters is examined for a range of scenarios.

Modeling Age×Major Gene Interaction by a Variance Component Approach

2001 ◽  
Vol 21 (S1) ◽  
pp. S849-S853 ◽  
Author(s):  
Sanjay S. Shete ◽  
Jianfang Chen ◽  
Xiaojun Zhou ◽  
Christopher I. Amos
Keyword(s):  
Variance Component ◽  
Major Gene ◽  
Gene Interaction ◽  
Component Approach ◽  
Variance Component Approach

A variance component approach to dichotomous trait linkage analysis using a threshold model

1997 ◽  
Vol 14 (6) ◽  
pp. 987-992 ◽  
Author(s):  
Ravindranath Duggirala ◽  
Jeff T. Williams ◽  
Sarah Williams-Blangero ◽  
John Blangero
Keyword(s):  
Linkage Analysis ◽  
Variance Component ◽  
Threshold Model ◽  
Component Approach ◽  
Variance Component Approach ◽  
Dichotomous Trait

scholarly journals Simple deterministic identity-by-descent coefficients and estimation of QTL allelic effects in full and half sibs

2002 ◽  
Vol 80 (3) ◽  
pp. 237-243 ◽  
Author(s):  
Y. NAGAMINE ◽  
S. A. KNOTT ◽  
P. M. VISSCHER ◽  
C. S. HALEY
Keyword(s):  
Marker Assisted Selection ◽  
Variance Component ◽  
Marker Locus ◽  
Variance Component Analysis ◽  
Mcmc Methods ◽  
Identity By Descent ◽  
Simple Method ◽  
Component Approach ◽  
Outbred Populations ◽  
Variance Component Approach

Accurate and rapid methods for the detection of quantitative trait loci (QTLs) and evaluation of consequent allelic effects are required to implement marker-assisted selection in outbred populations. In this study, we present a simple deterministic method for estimating identity-by-descent (IBD) coefficients in full- and half-sib families that can be used for the detection of QTLs via a variance-component approach. In a simulated dataset, IBD coefficients among sibs estimated by the simple deterministic and Markov chain Monte Carlo (MCMC) methods with three or four alleles at each marker locus exhibited a correlation of greater than 0·99. This high correlation was also found in QTL analyses of data from an outbred pig population. Variance component analysis used both the simple deterministic and MCMC methods to estimate IBD coefficients. Both procedures detected a QTL at the same position and gave similar test statistics and heritabilities. The MCMC method, however, required much longer computation than the simple method. The conversion of estimated QTL genotypic effects into allelic effects for use in marker-assisted selection is also demonstrated.

PREFERENSI PENEMPELAN, PERTUMBUHAN, DAN SINTASAN LARVA TERIPANG PASIR, Holothuria scabra PADA SUBSTRAT LAMUN YANG BERBEDA

2017 ◽  
Vol 11 (3) ◽  
pp. 249
Author(s):  
Lisa Fajar Indriana ◽  
Yuli Afrianti ◽  
Sitti Hilyana ◽  
Muhammad Firdaus Firdaus
Keyword(s):  
Survival Rate ◽  
Economic Value ◽  
Growth And Survival ◽  
Holothuria Scabra ◽  
Enhalus Acoroides ◽  
Randomized Design ◽  
Settlement Substrate ◽  
Cymodocea Rotundata ◽  
Syringodium Isoetifolium ◽  
Cymodocea Serrulata

Teripang pasir, Holothuria scabra merupakan komoditas hasil laut yang bernilai ekonomis tinggi. Penangkapan berlebihan stok di alam mendorong berkembangnya kegiatan budidaya. Penempelan merupakan fase kritis pada larva teripang karena terjadi peralihan sifat planktonis ke bentik yang memerlukan substrat. Penelitian ini bertujuan untuk mengetahui preferensi penempelan, pertumbuhan, dan sintasan larva H. scabra fase penempelan pada substrat lamun yang berbeda. Penelitian menggunakan metode rancangan acak lengkap dengan perlakuan empat jenis daun lamun berbeda dan lima ulangan. Perlakuan terdiri atas Enhalus acoroides (L-1), Syringodium isoetifolium (L-2), Cymodocea serrulata (L-3), dan Cymodocea rotundata (L-4). Jumlah awal larva sebanyak 1.000 individu dan substrat dirangkai dengan luasan yang sama sebesar 12 cm x 17 cm untuk setiap unit penelitian. Hasil penelitian menunjukkan jenis lamun yang digunakan sebagai substrat berpengaruh secara nyata terhadap preferensi penempelan dan sintasan larva teripang pasir, namun tidak berpengaruh terhadap pertumbuhan. E. acoroides menunjukkan hasil terbaik dengan preferensi penempelan 0,26 ind. cm-2 dan sintasan 10,66%; sehingga layak digunakan sebagai substrat penempelan dalam pembenihan teripang pasir, H. scabra.Holothuria scabra larvae on different seagrass substrates. By: Lisa Fajar Indriana, Yuli Afrianti, Sitti Hilyana, and Muhammad FirdausSandfish Holothuria scabra is marine commodities with a high economic value. Overfishing of natural stocks has compelled an interest to begin aquaculture practice. Settlement is a critical phase for the planktonic larvae as they will transform to benthic form in the presence of substrate. This study aims to evaluate the settlement preferences, growth, and survival rate of H. scabra larvae settled on different seagrass leaves. The research was conducted using the Completely randomized design with four different species of seagrass leaves and five replications. The treatments consist of Enhalus acoroides (L-1), Syringodium isoetifolium (L-2), Cymodocea serrulata (L-3), and Cymodocea rotundata (L-4). Initial number of larvae was 1,000 individuals and the substrate was set with same widthof 12 cm x 17 cm for each unit. Results of the experiment indicated that settlement preference and survival rate of H. scabra larvae was significantly affected by seagrass used as substrate while no significantly differences was observed for growth of larvae. E. acoroides showed the best result with 0.26 ind. cm-2 settelement preference and 10.66% survival rate, so that suitable to be used as settlement substrate in H. scabra hatchery.

scholarly journals Administration of Probiotic sanolife Mic-S on Biological Performance of Vanamei Shrimp (Litopenaeus vannamei) PL 10

2021 ◽  
Vol 3 (8) ◽  
pp. 42-57
Author(s):  
Hasim Hasim ◽  
Nadia Baidi ◽  
Syamsuddin Syamsuddin ◽  
Rully Tuiyo
Keyword(s):  
Feed Efficiency ◽  
Economic Value ◽  
Feed Conversion ◽  
Shrimp Culture ◽  
Growth And Survival ◽  
Crude Fiber Content ◽  
Weight Growth ◽  
Randomized Design ◽  
Biological Performance ◽  
Different Doses

Vannamei shrimp is a fishery commodity that has important economic value for Indonesia. This is indicated by the increasing number and value of exports of this commodity. One of the efforts to encourage the production of vaname shrimp is through the use of probiotics. sanolife-MIC is a probiotic widely used in shrimp culture. The aim of the study was to analyze the feed profile and biological performance of Vaname PL 10 shrimp fed pellets with the Sanolife MIC-S probiotic capsule at different doses. The research method used is an experimental method using a completely randomized design (CRD) with four treatments (A: probiotic 0 gr/kg feed; B: probiotic 10 gr/kg feed; C: probiotic 12 gr/kg feed; D: probiotic 14 g/kg feed) and three replicates. What was tested in the study were probiotic profile tests, growth, feed efficiency and feed conversion. The data obtained were analyzed using ANOVA. The results showed that the feed profile that was encapsulated using sanolife MIC-S, the protein value, moisture content and ash content for the feed were shown by treatment B. The best fat content was treatment C. The best crude fiber content was treatment D. Weight growth rate, ratio The best feed conversion and feed efficiency was shown by treatment B, while the length growth and survival was indicated by treatment C.

scholarly journals Cave bats in Jamaica

Oryx ◽  
1986 ◽  
Vol 20 (1) ◽  
pp. 27-30 ◽  
Author(s):  
Donald A. McFarlane
Keyword(s):  
Endemic Species ◽  
Economic Value ◽  
Mammal Species ◽  
The Past ◽  
Evolution And Development

Jamaica has 22 native mammal species. One of these is an endangered rodent, the Jamaican hutia Geocapromys browni; the rest are all bats. Fifteen of these bats depend entirely or significantly on caves as roost sites, including two endemic species and seven endemic subspecies. These cave-dwelling bats often form large colonies whose guano deposits are of significant economic value as fertilizer, but which are vulnerable to disturbance and roost destruction. The author, who has visited and worked in many of Jamaica's bat caves over the past eight years, is currently researching the evolution and development of the Antillean bat faunas.

A quantitative trait locus influencing estrogen levels maps to a region homologous to human chromosome 20

2001 ◽  
Vol 5 (2) ◽  
pp. 75-80 ◽  
Author(s):  
LISA J. MARTIN ◽  
JOHN BLANGERO ◽  
JEFFREY ROGERS ◽  
MICHAEL C. MAHANEY ◽  
JAMES E. HIXSON ◽  
...  
Keyword(s):  
Quantitative Trait Locus ◽  
Human Chromosome ◽  
Quantitative Trait ◽  
Potential Candidate ◽  
General Pedigree ◽  
Genome Wide ◽  
A Genome ◽  
Component Approach ◽  
Trait Locus ◽  
Variance Component Approach

Estrogen, a steroid hormone, regulates reproduction and has been implicated in several diseases. We performed a genome-wide scan using multipoint linkage analysis implemented in a general pedigree-based variance component approach to identify genes with measurable effects on variation in estrogen levels in baboons. A microsatellite polymorphism, D20S171, located on human chromosome 20q13.11, showed strong evidence of linkage with a LOD score of 3.06 ( P = 0.00009). This region contains several potential candidate genes including melanocortin 3 receptor ( MC3R), cytochrome P-450 subfamily XXIV ( CYP24), and breast carcinoma amplified sequence ( BCAS1). This is the first evidence of a quantitative trait locus with a significant effect on estrogen.

scholarly journals Experiences in selecting on a total merit index in the Austrian fleckvieh breed

2006 ◽  
Vol 22 (1-2) ◽  
pp. 17-27 ◽  
Author(s):  
J. Miesenberger ◽  
C. Fuerst
Keyword(s):  
Selection Index ◽  
Cattle Breed ◽  
International Exchange ◽  
Production Traits ◽  
Economic Gain ◽  
Milk Traits ◽  
Breeding Values ◽  
Breeding Objective ◽  
Economic Weights ◽  
Estimated Breeding Values

Spotted cattle breed is the most common breed in Austria. Austrian Spotted cattle breed is bred as a dual purpose breed for more than 100 years. The breeding objective has changed over the time according to the different economic importance of the traits and according to the different possibilities in using estimated breeding values (EBVs) for selection. Since 1998 the breeding objective is defined as the aggregate genotype of production traits and functional traits. All economically important traits are combined according to their economic weights in the total merit index (TMI). The TMI is calculated by combining the EBVs of all traits using a selection index procedure. The index weights (b-values) are estimated depending on the reliabilities of the EBVs and are therefore different from animal to animal. Considering the intensive international exchange of semen from the best bulls, the cooperation in the breeding programs and the similar economic situation in agriculture the breeding organizations of Germany and Austria decided to make a joint across-country evaluation for all traits. Since November 2002 breeding values for all traits and as a logical conclusion the TMI are evaluated jointly. The result is a high acceptance of the EBVs and the TMI by the farmers because of smaller changes of the breeding values for national and foreign bulls between consecutive evaluations. The realized economic gain in the different traits is very close to the expected economic gain. In the last 10 years on average 88.2 % of the economic gain were realized in the milk traits, 4.2 % in the beef traits and 7.6 % were realized in the fitness traits.

Sign in / Sign up

Export Citation Format

Share Document