scholarly journals Impacts of genetic selection on Sequoia sempervirens mini-cutting rooting and initial growth in the field

2021 ◽  
Vol 51 ◽  
Author(s):  
Queli Cristina Lovatel ◽  
Gabriel Teixeira da Rosa ◽  
Alexandra Cristina Schatz Sá ◽  
Betel Cavalcante Lopes ◽  
Erasmo Luis Tonett ◽  
...  

Background: Vegetative propagation from superior individuals allows multiple copies of plants that are genetically identical to the parent plant to be obtained. However, vegetative propagation success varies among individual genotypes, with some clones having more difficulty forming roots than others. The aim of this study was to evaluate the genetic gain in Sequoia sempervirens (D.Don) Endl. clones using parameters describing vegetative propagation success and initial growth in field. Methods: Vegetative propagation success was quantified for 16 clones in a completely randomised design consisting of 10 replications, each containing 10 mini-cuttings. At 90 days, rooting (RT), survival (SV) and the number of new shoots (NS) were evaluated. Performance after planting in the field was assessed using 13 clones from the previous experiment, arranged in linear parcels of 10 plants with 8 replicates. After 18 months, survival (SV), stem diameter (SD), height (H) and dominance breakdown (DB) were assessed. Estimates of variance components, heritability and genetic correlations were obtained using the Selegen-REML/BLUP software. Results: The mini cuttings of the 16 clones had a coefficient of genetic variation (CVgi%) of 32.32% for RT, 5.44% for SV and 5.35% for NS. The heritability of the total genetic effects (H2 g) for RT was 0.68. The clones with the best predicted genotypic classifications for the characteristics evaluated in the field were A116, A140 and A138 for SV, A126, A140 and A138 for SD, A138, A140 and A117 for H and A138, A228 and A116 for DB. Conclusions: In general, it was possible to obtain high genetic gain for rooting and medium gain for dendrometric variables in the field.

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Simone Savoia ◽  
Andrea Albera ◽  
Alberto Brugiapaglia ◽  
Liliana Di Stasio ◽  
Alessio Cecchinato ◽  
...  

Abstract Background The possibility of assessing meat quality traits over the meat chain is strongly limited, especially in the context of selective breeding which requires a large number of phenotypes. The main objective of this study was to investigate the suitability of portable infrared spectrometers for phenotyping beef cattle aiming to genetically improving the quality of their meat. Meat quality traits (pH, color, water holding capacity, tenderness) were appraised on rib eye muscle samples of 1,327 Piemontese young bulls using traditional (i.e., reference/gold standard) laboratory analyses; the same traits were also predicted from spectra acquired at the abattoir on the intact muscle surface of the same animals 1 d after slaughtering. Genetic parameters were estimated for both laboratory measures of meat quality traits and their spectra-based predictions. Results The prediction performances of the calibration equations, assessed through external validation, were satisfactory for color traits (R2 from 0.52 to 0.80), low for pH and purge losses (R2 around 0.30), and very poor for cooking losses and tenderness (R2 below 0.20). Except for lightness and purge losses, the heritability estimates of most of the predicted traits were lower than those of the measured traits while the genetic correlations between measured and predicted traits were high (average value 0.81). Conclusions Results showed that NIRS predictions of color traits, pH, and purge losses could be used as indicator traits for the indirect genetic selection of the reference quality phenotypes. Results for cooking losses were less effective, while the NIR predictions of tenderness were affected by a relatively high uncertainty of estimate. Overall, genetic selection of some meat quality traits, whose direct phenotyping is difficult, can benefit of the application of infrared spectrometers technology.


Antibiotics ◽  
2021 ◽  
Vol 10 (7) ◽  
pp. 829
Author(s):  
Wim Gorssen ◽  
Dominiek Maes ◽  
Roel Meyermans ◽  
Jürgen Depuydt ◽  
Steven Janssens ◽  
...  

The use of antimicrobials in animal production is under public debate, mainly due to the risk of transfer of resistance to pathogenic bacteria in humans. Therefore, measures have been taken during the last few decades to reduce antibiotic usage in animals, for instance, by national monitoring programmes and by improving animal health management. Although some initiatives exist in molecular genetic selection, quantitative genetic selection of animals towards decreased antibiotic usage is an underexplored area to reduce antibiotic usage. However, this strategy could yield cumulative effects. In this study, we derived new phenotypes from on-farm parenteral antibiotic records from commercially grown crossbred finishing pigs used in the progeny test of Piétrain terminal sires to investigate the heritability of antibiotics usage. Parenteral antibiotic records, production parameters and pedigree records of 2238 full-sib pens from two experimental farms in Belgium between 2014 and 2020 were analysed. Heritability estimates were moderate (18–44%) for phenotypes derived from all antibiotic treatments, and low (1–15%) for phenotypes derived from treatments against respiratory diseases only. Moreover, genetic correlations between these new phenotypes and mortality were low to moderate (0.08–0.60) and no strong adverse genetic correlations with production traits were found. The high heritabilities and favourable genetic correlations suggest these new phenotypes, derived from on-farm antibiotics records, to be promising for inclusion in future pig breeding programs to breed for a decrease in antibiotics usage.


2018 ◽  
Vol 58 (10) ◽  
pp. 1966
Author(s):  
Purna Kandel ◽  
Sylvie Vanderick ◽  
Marie-Laure Vanrobays ◽  
Hélène Soyeurt ◽  
Nicolas Gengler

Methane (CH4) emission is an important environmental trait in dairy cows. Breeding aiming to mitigate CH4 emissions require the estimation of genetic correlations with other economically important traits and the prediction of their selection response. In this study, test-day CH4 emissions were predicted from milk mid-infrared spectra of Holstein cows. Predicted CH4 emissions (PME) and log-transformed CH4 intensity (LMI) computed as the natural logarithm of PME divided by milk yield (MY). Genetic correlations of PME and LMI with traits used currently were approximated from correlations between estimated breeding values of sires. Values were for PME with MY 0.06, fat yield (FY) 0.09, protein yield (PY) 0.13, fertility 0.17; body condition score (BCS) –0.02; udder health (UDH) 0.22; and longevity 0.22. As expected by its definition, values were negative for LMI with production traits (MY –0.61; FY –0.15 and PY –0.40) and positive with fertility (0.36); BCS (0.20); UDH (0.08) and longevity (0.06). The genetic correlations of 33 type traits with PME ranged from –0.12 to 0.25 and for LMI ranged from –0.22 to 0.18. Without selecting PME and LMI (status quo) the relative genetic change through correlated responses of other traits were in PME by 2% and in LMI by –15%, but only due to the correlated response to MY. Results showed for PME that direct selection of this environmental trait would reduce milk carbon foot print but would also affect negatively fertility. Therefore, more profound changes in current indexes will be required than simply adding environmental traits as these traits also affect the expected progress of other traits.


FLORESTA ◽  
2014 ◽  
Vol 45 (2) ◽  
pp. 383 ◽  
Author(s):  
Márcio Carlos Navroski ◽  
Mariane De Oliveira Pereira ◽  
André Felipe Hess ◽  
Raul Silvestre ◽  
Alessandro Camargo Ângelo ◽  
...  

Objetivou-se com o estudo verificar resgate vegetativo, enraizamento de estacas e adaptação das mudas enraizadas em sistema de minijardim clonal de Sequoia sempervirens. Realizou-se a decepa de cinco indivíduos com 20 anos de idade e após foi contabilizada a capacidade de emissão de brotações. Com as brotações, foram confeccionadas estacas, as quais foram submetidas a diferentes concentrações de ácido indolacético (AIA) (0, 2000, 4000 e 6000 mg.L-1). Foram avaliadas a porcentagem de enraizamento e o número e comprimento de raízes 160 dias após o estaqueamento. O experimento foi instalado em DIC, com 5 repetições de 10 estacas. Após a formação das mudas com as estacas enraizadas, elas foram transplantadas para vasos, para a formação do minijardim clonal. O resgate vegetativo através da decepa de árvores apresentou potencialidade para produção de estacas de sequoia e revigoramento do material. O uso entre 2000 e 4000 mg.L-1 de AIA aumentou a porcentagem de enraizamento e também o número e comprimento de raízes formadas. O minijardim clonal de sequoia mostrou ser uma boa opção para a multiplicação clonal da espécie. A clonagem da sequoia pode auxiliar tanto no melhoramento convencional como em plantios comerciais da espécie, principalmente no Sul do Brasil, local onde encontra condições adequadas para seu crescimento.Palavras-chave: Silvicultura clonal; coníferas; rejuvenescimento; minijardim clonal. AbstractRescue and vegetative propagation of Sequoia sempervirens. The objective of the study to verify the vegetative rescue, rooting cuttings and rooted plants adapt in mini-clonal hedge of Sequoia sempervirens system. Was held coppicing five individuals aged 20 years old and was recorded after the ability to shoot emission. Shoots with different concentrations of indole acetic acid were applied (IAA) (0, 2000, 4000 and 6000 mg.L-1) in cuttings made by evaluating the percentage of rooting, number and length of roots 160 days after striking. The experiment was a completely randomized with five replicates of 10 cuttings. After the formation of seedlings with rooted cuttings, these were transplanted to pots for the formation of mini-clonal hedge. The vegetative rescue through coppicing trees showed potential for the production of cuttings sequoia and reinvigoration of the material. The use from 2000 to 4000 mg.L-1 IAA increased rooting percentage and the number and length of roots formed. The mini-clonal hedge of sequoia proved to be a good option for clonal multiplication of the species. Cloning of sequoia can help both conventional breeding and for commercial plantations of the species, especially in southern Brazil, where finds suitable conditions for their growth.Keywords: Clonal forestry; conifers; rejuvenation; mini-clonal hedge.


2016 ◽  
Vol 59 (2) ◽  
pp. 243-248 ◽  
Author(s):  
Hafedh Ben Zaabza ◽  
Abderrahmen Ben Gara ◽  
Hedi Hammami ◽  
Mohamed Amine Ferchichi ◽  
Boulbaba Rekik

Abstract. A multi-trait repeatability animal model under restricted maximum likelihood (REML) and Bayesian methods was used to estimate genetic parameters of milk, fat, and protein yields in Tunisian Holstein cows. The estimates of heritability for milk, fat, and protein yields from the REML procedure were 0.21 ± 0.05, 0.159 ± 0.04, and 0.158 ± 0.04, respectively. The corresponding results from the Bayesian procedure were 0.273 ± 0.02, 0.198 ± 0.01, and 0.187 ± 0.01. Heritability estimates tended to be larger via the Bayesian than those obtained by the REML method. Genetic and permanent environmental variances estimated by REML were smaller than those obtained by the Bayesian analysis. Inversely, REML estimates of the residual variances were larger than Bayesian estimates. Genetic and permanent correlation estimates were on the other hand comparable by both REML and Bayesian methods with permanent environmental being larger than genetic correlations. Results from this study confirm previous reports on genetic parameters for milk traits in Tunisian Holsteins and suggest that a multi-trait approach can be an alternative for implementing a routine genetic evaluation of the Tunisian dairy cattle population.


2013 ◽  
Vol 56 (1) ◽  
pp. 564-572 ◽  
Author(s):  
F. Ghafouri-Kesbi

Abstract. The aim of the present study was to estimate (co)variance components and genetic parameters for average daily gain from birth to weaning (ADGa), weaning to 6 months (ADGb), weaning to 9 months (ADGc), 6 months to 9 months (ADGd) and corresponding Kleiber ratios (KRa, KRb, KRc and KRd) in Mehraban sheep. A derivative-free algorithm combined with a series of six univariate linear animal models was used to estimate phenotypic variance and its direct, maternal and residual components. In addition, bivariate analyses were done to estimate (co)variance components between traits. Estimates of direct heritability (h2) were 0.10, 0.11, 0.16, 0.09, 0.13, 0.13, 0.15 and 0.08 for ADGa, ADGb, ADGc, ADGd, KRa, KRb, KRc and KRd, respectively and indicate that in Mehraban sheep genes contribute very little to the variance of the growth rate and Kleiber ratio. Estimates of maternal heritability (m2) were 0.10, 0.08 and 0.05 for ADGa, KRa and KRb, respectively. Direct additive genetic correlations ranged from −0.32 (KRa-KRd) to 0.99 (ADGb-KRb) and phenotypic correlations ranged from −0.53 (ADGa- ADGd) to 0.99 (ADGa-KRa). Estimates of direct heritability and genetic correlations show that genetic improvement in efficiency of feed utilization through selection programmes is possible, though it would generate a relatively slow genetic progress.


PLoS ONE ◽  
2020 ◽  
Vol 15 (12) ◽  
pp. e0244021
Author(s):  
Marco Antônio Peixoto ◽  
Rodrigo Silva Alves ◽  
Igor Ferreira Coelho ◽  
Jeniffer Santana Pinto Coelho Evangelista ◽  
Marcos Deon Vilela de Resende ◽  
...  

Random regression models (RRM) are a powerful tool to evaluate genotypic plasticity over time. However, to date, RRM remains unexplored for the analysis of repeated measures in Jatropha curcas breeding. Thus, the present work aimed to apply the random regression technique and study its possibilities for the analysis of repeated measures in Jatropha curcas breeding. To this end, the grain yield (GY) trait of 730 individuals of 73 half-sib families was evaluated over six years. Variance components were estimated by restricted maximum likelihood, genetic values were predicted by best linear unbiased prediction and RRM were fitted through Legendre polynomials. The best RRM was selected by Bayesian information criterion. According to the likelihood ratio test, there was genetic variability among the Jatropha curcas progenies; also, the plot and permanent environmental effects were statistically significant. The variance components and heritability estimates increased over time. Non-uniform trajectories were estimated for each progeny throughout the measures, and the area under the trajectories distinguished the progenies with higher performance. High accuracies were found for GY in all harvests, which indicates the high reliability of the results. Moderate to strong genetic correlation was observed across pairs of harvests. The genetic trajectories indicated the existence of genotype × measurement interaction, once the trajectories crossed, which implies a different ranking in each year. Our results suggest that RRM can be efficiently applied for genetic selection in Jatropha curcas breeding programs.


2021 ◽  
Author(s):  
Wim Gorssen ◽  
Dominiek Maes ◽  
Roel Meyermans ◽  
Jurgen Depuydt ◽  
Steven Janssens ◽  
...  

The use of antimicrobials in animal production is under public debate, mainly due to the risk of transfer of resistance to pathogenic bacteria in humans. Therefore, measures have been taken during the last decades to reduce antibiotic usage in animals, for instance by national monitoring programmes and by improving animal health management. Although some initiatives exist in molecular genetic selection, quantitative genetic selection of animals towards decreased antibiotic usage is an underexplored area to reduce antibiotic usage. However, this strategy could yield cumulative effects. In this study we derived new phenotypes from on-farm parenteral antibiotic records from commercially grown crossbred finishing pigs used in the progeny test of Pietrain terminal sires to investigate the heritability of antibiotics usage. Parenteral antibiotic records, production parameters and pedigree records of 2238 full-sib pens from two experimental farms in Belgium between 2014 and 2020 were analysed. Heritability estimates were moderate (18-44%) for phenotypes derived from all antibiotic treatments, and low (1-15%) for phenotypes derived from treatments against respiratory diseases only. Moreover, genetic correlations between these new phenotypes and mortality were low to moderate (0.08-0.60) and no strong adverse genetic correlations with production traits were found. The high heritabilities and favourable genetic correlations suggest these new phenotypes derived from on-farm antibiotics records to be promising for inclusion in future pig breeding programs to breed for a decrease in antibiotics usage.


2021 ◽  
Vol 99 (Supplement_3) ◽  
pp. 238-239
Author(s):  
Maria Paula Negreiros ◽  
Elisa Peripolli ◽  
Claudio U Magnabosco ◽  
Nayanny Guimarães ◽  
Raysildo Lôbo ◽  
...  

Abstract We evaluated a novel frame score system for Nellore cattle raised on pasture (Guimarães et al., 2020 J, Anim. Sci. 98 (Suppl. 4)). Growth traits included age-adjusted weights (kg) at birth (W0), 120 (W120), 210 (W210) and 450 (W450) days of age, and adult weight (AW). Carcass traits (by ultrasound) included ribeye area (REA, cm2), 12th-13th rib backfat (BF, mm), rump fat (RF, mm), and intramuscular fat (IMF, %). Feed efficiency traits included residual feed intake (RFI, kg of DM/d) and DM intake (DMI, kg/d). We applied the previously developed equations (that also include hip height (HH, cm) and age to 12,049 records from the National Association of Breeders and Researchers (ANCP) database:FSmales= -20.35 + 0.1305*REA + 0.2633*BF - 0.5901*RF+ 0.1139*HH + 0.0056*AGEFSfemales = -11.87 + 0.1316*REA - 0.2457*BF - 0.6218*RF + 0.1139*HH + 0.0009507*AGEThe (co)variance components and genetic parameters were estimated using a linear animal model or a threshold animal model depending on the trait. The heritability estimate for frame score was moderate (0.30). Estimated genetic correlations were moderate for growth traits (W0, 0.51; W120, 0.41; W210, 0.35; W450, 0.29; AW, 0.39). Estimated genetic correlations for carcass and efficiency traits ranged from low to high (REA, 0.50; BF, -0.25; RF, -0.84; IMF, -0.15; DMI, 0.29; RFI, 0.10). The estimates support the notion that larger frame animals are heavier, leaner and later maturing, and less feed efficient. The new frame score may be a useful tool for genetic selection of animals that are best suited to their environment.


2019 ◽  
Vol 97 (Supplement_3) ◽  
pp. 56-56
Author(s):  
Han A Mulder ◽  
Marieke Poppe ◽  
Tom V L Berghof

Abstract In their lifetime, animals experience various environmental perturbations, such as heat stress, a disease or a change in feed, which require a response. Animals differ in their capacity to respond to various perturbations; this is called resilience, which is the capacity of animals to be minimally affected by perturbations or to rapidly return to the state before exposure to perturbations. The main obstacle in research on genetics of resilience is how to define and quantify resilience. Big data offers great opportunities because longitudinal profiles of animals, such as feed intake, body weight, milk yield or egg production, contain information about how animals respond to perturbations. The objectives of our research were to define resilience indicators and estimate heritable variation in resilience indicators and to estimate associations with existing health and longevity traits to assess the utility of resilience indicators to improve resilience by breeding. The resilience indicators studied were log-transformed variance of deviations (LnVar), lag-1 autocorrelation (Auto) of deviations and skewness of deviations (Skew) based on daily milk yield in dairy cattle and four-weekly body weight measures in laying hens. In dairy cattle, we estimated a heritability of 0.20–0.24 for LnVar, a heritability of 0.08–0.10 for Auto, and a heritability of 0.01 for Skew. The strongest genetic correlations between a resilience indicator and existing health and longevity traits were found for LnVar with udder health (-0.22 to -0.33), ketosis (-0.27 to -0.33) and longevity (-0.29 to -0.34). In laying hens, we estimated similar heritabilities for the three resilience indicators: 0.10 for LnVar, 0.11 for Auto, and 0.09 for Skew. We found predictive value of LnVar breeding values for lesion scores after challenge with an E-coli infection. These results show that especially the variance of deviations is a promising resilience indicator to improve resilience and health in animals by genetic selection.


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