scholarly journals Sustainable Intensification of Beef Production in the Tropics: The Role of Genetically Improving Sexual Precocity of Heifers

Animals ◽  
2022 ◽  
Vol 12 (2) ◽  
pp. 174
Author(s):  
Gerardo Alves Fernandes Júnior ◽  
Delvan Alves Silva ◽  
Lucio Flavio Macedo Mota ◽  
Thaise Pinto de Melo ◽  
Larissa Fernanda Simielli Fonseca ◽  
...  
Keyword(s):  
Genetic Improvement ◽  
Direct Selection ◽  
Parameter Estimates ◽  
Zebu Cattle ◽  
Environment Interaction ◽  
Beef Production ◽  
Breeding Programs ◽  
Sexual Precocity ◽  
Use Of Resources ◽  
Selection For

Increasing productivity through continued animal genetic improvement is a crucial part of implementing sustainable livestock intensification programs. In Zebu cattle, the lack of sexual precocity is one of the main obstacles to improving beef production efficiency. Puberty-related traits are complex, but large-scale data sets from different “omics” have provided information on specific genes and biological processes with major effects on the expression of such traits, which can greatly increase animal genetic evaluation. In addition, genetic parameter estimates and genomic predictions involving sexual precocity indicator traits and productive, reproductive, and feed-efficiency related traits highlighted the feasibility and importance of direct selection for anticipating heifer reproductive life. Indeed, the case study of selection for sexual precocity in Nellore breeding programs presented here show that, in 12 years of selection for female early precocity and improved management practices, the phenotypic means of age at first calving showed a strong decreasing trend, changing from nearly 34 to less than 28 months, with a genetic trend of almost −2 days/year. In this period, the percentage of early pregnancy in the herds changed from around 10% to more than 60%, showing that the genetic improvement of heifer’s sexual precocity allows optimizing the productive cycle by reducing the number of unproductive animals in the herd. It has a direct impact on sustainability by better use of resources. Genomic selection breeding programs accounting for genotype by environment interaction represent promising tools for accelerating genetic progress for sexual precocity in tropical beef cattle.

Genetic improvement of resistance to cyclaneusma needle cast in Pinus radiata

2019 ◽  
Vol 49 (2) ◽  
pp. 128-133 ◽  
Author(s):  
Mari Suontama ◽  
Yongjun Li ◽  
Charlie B. Low ◽  
Heidi S. Dungey
Keyword(s):  
New Zealand ◽  
Pinus Radiata ◽  
Genetic Improvement ◽  
Genetic Correlations ◽  
Tree Height ◽  
Progeny Testing ◽  
Environment Interaction ◽  
Needle Cast ◽  
Genotype Environment Interaction ◽  
Selection For

Progeny testing of resistance to needle loss caused by Cyclaneusma minus (cyclaneusma needle cast) has been included in the needle disease resistance strategy of Pinus radiata D. Don in New Zealand since the late 1970s. Data on progeny trials, two in the North Island of New Zealand and one in Tasmania, Australia, were available to estimate heritability between trait genetic correlations and genotype × environment interaction. Resistance to cyclaneusma needle cast had moderate estimates of heritability (0.25 to 0.46) at all sites. Genetic correlations between the assessed traits indicated that selection for faster early growth, i.e., tree height at age 4 years and diameter at breast height at age 6 years, favours trees that are prone to Cyclaneusma infection, while a favourable genetic association between resistance to cyclaneusma needle cast and productivity was evident at a later assessment at age 9 years. No significant genotype × environment interaction was found for resistance to cyclaneusma needle cast; however, stability of genotypes across a wider range of environments and with a high genetic connectedness requires more research. Considerable genetic improvement can be achieved for resistance to cyclaneusma needle cast and indirect selection for the trait should be pursued by selecting for productivity and culling susceptible genotypes from breeding.

scholarly journals Selection indexes for genetic improvement of yearling weight in Egyptian buffaloes

2010 ◽  
Vol 53 (4) ◽  
pp. 436-446
Author(s):  
K. A. Shahin ◽  
O. Y. Abdallah ◽  
T. A. Fooda ◽  
K. A. Mourad
Keyword(s):  
Body Weight ◽  
Genetic Improvement ◽  
Average Daily Gain ◽  
Breeding Value ◽  
Direct Selection ◽  
Body Weights ◽  
Practical Standpoint ◽  
Selection Indexes ◽  
Selection For ◽  
Daily Gain

Abstract. Estimates of genetic and phenotypic parameters for body weight at birth, 3, 6, 9, and 12 months of age, and for preweaning and postweaning average daily gain were computed and used to construct 14 selection indexes to improve the 12-month weight in Egyptian buffaloes. The full index incorporating body weight at birth, 3, 6, 9 and 12 months of age had the highest correlation with aggregate breeding value (rTI=0.63). The correlation fell to 0.62 when body weight at birth and 3 months were omitted from the index. Selection for body weight at 12 months of age alone is expected to be 76.2 % as efficient as selection for the full index. The maximum expected genetic gain in 12-month body weight was 8.85 kg/generation when all five body weights were included in the index; this decreased to 8.09 kg/generation when body weights at birth, 3 and 6 months were excluded and further decreased to 6.94 kg/ generation when selection based on yearling weight only. From the practical standpoint, selection on I5 involving body weight at 9 month of age can be considered as the best for improving body weight at 12 month since its application is earlier, less expensive, higher accuracy than any index excluding body weight at 12 month and giving reasonable amount (+5.39 kg) improvement in yearling weight as compared to direct selection (+6.94 kg).

56 Awardee Talk: Genetic Improvement of Disease Resilience

2021 ◽  
Vol 99 (Supplement_3) ◽  
pp. 31-31
Author(s):  
Jack C Dekkers ◽  
Frederic Fortin ◽  
Michael Dyck ◽  
John Harding ◽  
Graham Plastow
Keyword(s):  
Infectious Disease ◽  
Genetic Improvement ◽  
Genetic Basis ◽  
Genetic Resistance ◽  
Swine Industry ◽  
Breeding Programs ◽  
Potential Indicator ◽  
Selection For ◽  
Indicator Traits ◽  
Cost Components

Abstract Infectious disease represents one of the largest cost components to the swine industry, incurring veterinary costs, loss of pigs due to mortality, reduced performance, and reduced animal welfare. Strategies to reduce the incidence and impact of infectious disease include biosecurity, vaccination, veterinary treatment, and selection for genetic resistance. However, biosecurity protocols that keep most infectious pathogens out are not feasible at the commercial level in hog-dense regions, effective vaccines are only available and/or efficacious for some pathogens, and complete genetic resistance is also limited to only a few pathogens (e.g. F18 E.coli) or is only possible to achieve by gene editing (e.g. the PRRS-resistant pig created by editing the CD163 gene). Given these limitations, commercial pigs will continue to be exposed to and infected by pathogens for the foreseeable future. In such a scenario, the ability of an animal to clear the infection while maintaining performance is an important characteristic, which is referred to as disease resilience and is a useful target for inclusion in breeding programs. However, collection of data on disease resilience for genetic improvement requires animals to be exposed to disease, which is not possible in the nucleus herds of breeding programs that most selection is practiced in. To study the genetic basis of disease resilience and develop phenotypes, genetic tests, or indicator traits that could be used to select for disease resilience, a polymicrobial natural disease challenge model was established in grow-finish pigs at the Center de Développement du Porc du Québec, in collaboration with PigGen Canada. The purpose of this presentation is to present results on phenotypes that are relevant to disease resilience, including estimates of genetic parameters, and on potential indicator traits for disease resilience that could be collected in nucleus herds. Funding by Genome Canada, Genome Alberta, PigGen Canada, and USDA NIFA grant #2017-67007-26144.

scholarly journals Genotype × environment interaction in Tribolium castaneum

1964 ◽  
Vol 5 (3) ◽  
pp. 335-340 ◽  
Author(s):  
J. F. Kidwell ◽  
A. E. Freeman ◽  
L. H. Haverland ◽  
G. M. H. Rolfes
Keyword(s):  
Relative Humidity ◽  
Tribolium Castaneum ◽  
Total Variance ◽  
Direct Selection ◽  
Environment Interaction ◽  
Breeding Values ◽  
Genotype Environment Interaction ◽  
The Mean ◽  
Selection For ◽  
C 30

An experiment was conducted with the flour beetle, Tribolium castaneum to investigate genotype-environment interaction. Ninety-two matings of one male and three females were made at random from a large panmictic population. The females were transferred to individual containers after 4 days. Six daughters were randomly selected from each sire–dam pair and individually mated to unrelated males. Three of the six were placed in an incubator (33·3°C., 45% relative humidity) and three in a cabinet at room conditions (22·2–26·7°C., 30–35% relative humidity) and allowed to produce eggs during a 3-day period. Progeny were counted as pupae and larvae. The traits studied were number of pupae and number of pupae plus number of larvae. A transformation to (X +1)½ was required. A conventional least-squares model was employed, and a large environmental effect was observed. In the incubator the mean number of pupae was 13·4 and of pupae + larvae was 20·1 while the corresponding figures for room conditions were 3·3 and 9·2. Genotype-environment interaction accounted for 3·7 to 6·7% of the total variance for (pupae + 1)½ and 2·1 to 8·3% for (pupae + larvae+ 1)½. Heritability of the traits was essentially the same in both environments. The interaction was due to an increasing difference between environments in production associated with increasing breeding values of the sire, and to small changes in rank of breeding values on the two environments. As a result of the interaction, selection in one environment for production on the other would be expected to be only 71 to 72% as effective as direct selection for (pupae + 1)½ and 62 to 86% for (pupae + larvae + 1)½ even though the fraction of the total variance attributed to genotype-environmental interaction was less than 10%.

scholarly journals Genetic Improvement of Local Cattle Breeds in West Africa: A Review of Breeding Programs

2021 ◽  
Vol 13 (4) ◽  
pp. 2125
Author(s):  
Dominique Ouédraogo ◽  
Albert Soudré ◽  
Bernadette Yougbaré ◽  
Salifou Ouédraogo-Koné ◽  
Bienvenue Zoma-Traoré ◽  
...  
Keyword(s):  
West Africa ◽  
Genetic Improvement ◽  
Government Support ◽  
Zebu Cattle ◽  
Cattle Breeding ◽  
Breeding Programs ◽  
Milk Performance ◽  
Multiple Services ◽  
Farmer Livelihoods ◽  
National Economies

Cattle are one of the most important livestock species in West Africa, providing multiple services to farmers and contributing to national economies. Various breeding strategies have been implemented to enhance their productivity and have improved farmer livelihoods. This review describes cattle breeding experiences across West Africa, spanning the N’Dama breed in Mali, Senegal, and The Gambia to the breeds Azawak Zebu, Fulani Zebu, and taurine Baoulé in Burkina Faso. The main objectives of most breeding programs have been to optimize meat and milk performance of taurine and Zebu cattle as well as trypanotolerance of taurine cattle. In some cases, “closed nucleus” schemes have proven limited and so have evolved into “open nucleus” schemes. Recent community-based breeding programs have shown promise. The major challenges of breeding programs remain defining realistic breeding objectives and securing the involvement of stakeholders. All the strategies reviewed here have been funded externally within development or research projects that are often too short to yield tangible genetic improvement, and whether they will continue beyond those projects is uncertain. This review highlights the need for continuing government support to ensure the sustainability of local cattle breeding programs.

ESTIMASI NILAI HERITABILITAS BOBOT IKAN MAS VARIETAS PUNTEN DALAM PROGRAM SELEKSI INDIVIDU

2016 ◽  
Vol 11 (3) ◽  
pp. 217
Author(s):  
Estu Nugroho ◽  
Budi Setyono ◽  
Mochammad Su’eb ◽  
Tri Heru Prihadi
Keyword(s):  
Body Weight ◽  
Selection Response ◽  
Base Population ◽  
Breeding Programs ◽  
Male And Female ◽  
Body Weight Trait ◽  
Population Selection ◽  
Selection For ◽  
Weight Trait ◽  
Selection Of

Program pemuliaan ikan mas varietas Punten dilakukan dengan seleksi individu terhadap karakter bobot ikan. Pembentukan populasi dasar untuk kegiatan seleksi dilakukan dengan memijahkan secara massal induk ikan mas yang terdiri atas 20 induk betina dan 21 induk jantan yang dikoleksi dari daerah Punten, Kepanjen (delapan betina dan enam jantan), Kediri (tujuh betina dan 12 jantan), Sragen (27 betina dan 10 jantan), dan Blitar (15 betina dan 11 jantan). Larva umur 10 hari dipelihara selama empat bulan. Selanjutnya dilakukan penjarangan sebesar 50% dan benih dipelihara selama 14 bulan untuk dilakukan seleksi dengan panduan hasil sampling 250 ekor individu setiap populasi. Seleksi terhadap calon induk dilakukan saat umur 18 bulan pada populasi jantan dan betina secara terpisah dengan memilih berdasarkan 10% bobot ikan yang terbaik. Calon induk yang terseleksi kemudian dipelihara hingga matang gonad, kemudian dipilih sebanyak 150 pasang dan dipijahkan secara massal. Didapatkan respons positif dari hasil seleksi berdasarkan bobot ikan, yaitu 49,89 g atau 3,66% (populasi ikan jantan) dan 168,47 g atau 11,43% (populasi ikan betina). Nilai heritabilitas untuk bobot ikan adalah 0,238 (jantan) dan 0,505 (betina).Punten carp breeding programs were carried out by individual selection for body weight trait. The base population for selection activities were conducted by mass breeding of parent consisted of 20 female and 21 male collected from area Punten, eight female and six male (Kepanjen), seven female and 12 male (Kediri), 27 female and 10 male (Sragen), 15 female and 11 male (Blitar). Larvae 10 days old reared for four moths. Then after spacing out 50% of total harvest, the offspring reared for 14 months for selection activity based on the sampling of 250 individual each population. Selection of broodstock candidates performed since 18 months age on male and female populations separately by selecting based on 10% of fish with best body weight. Candidates selected broodstocks were then maintained until mature. In oder to produce the next generation 150 pairs were sets and held for mass spawning. The results revealed that selection response were positive, 49.89 g (3.66%) for male and 168.47 (11.43%) for female. Heritability for body weight is 0.238 (male) and 0.505 (female).

Evaluation of Large-Sunflower Lines of Sunflower on Quantitative Morphological Traits

2020 ◽  
pp. 46-55
Keyword(s):  
Fertility Restoration ◽  
Morphological Characters ◽  
Direct Selection ◽  
Oilseed Crops ◽  
Turkish Origin ◽  
Self Pollination ◽  
Special Area ◽  
Pericarp Color ◽  
Selection For ◽  
Selection Of

Confectionery sunflower - a special area of use of sunflower, which requires the creation of marketable seeds quality features. One of the possible ways to create large-fruited sunflower is to create production hybrids and lines. Objective: to evaluate the created new large-fruited sunflower lines by a complex of morphological characters and determine the best lines for use as large-seeds hybrids as parent components or source material. In 2016-2019 years on the basis of the Institute of Oilseed Crops NAAS a study was conducted to assess the economic characteristics of large-fruited sunflower lines. We studied a collection of 27 lines of large-seeds sources. The lines were created by direct selection or crossing and sampling: Reyny of Argentinean origin, Zaporizhzhya confectionery variety, confectionery hybrid with striped pericarp color of Israeli origin, white seed of Turkish origin, synthetic population - donor of complex resistance. To study from the collection, lines were drawn that went through at least 7 generations with selection for seed size. Experience has shown that the shortest growing season for lines 174d and KP11 was 99 days, and the longest for lines I2K670 was 109 days. In the studied collection, the greatest mass of 1000 seeds has the KP11-146.47g line, which is the mother component and does not have branching. The second by weight of 1000 seeds (109 g) stood out line 168v, which also had branches and pollen fertility restoration genes and will be used as the paternal form. The third largest is also one basket line ZKN51-100. The collection included lines originating from the same combination, but with a different morphotype for the presence and absence of branching. So, based on the combination of KP11 x Zaporizhzhya Confectionery, three lines were obtained. A mass of 1000 seeds was observed in 98-86 g, with the branching line having the largest mass of 1000 seeds. The lines created with one combination VK678 x ZKN32: with a branch 168a had a mass of 1000 seeds 95g, and a line 168b - without a branch 109 g. Of the two lines obtained from the descendants of the combination KP11 x the striped hybrid both had branches, but the seeds were much smaller (weight of 1000 seeds 59 and 79 g). The collection also studied samples created on the basis of varieties and populations 160c, 174, 175b, the mass of 1000 seeds of which turned out to be more acceptable for large-fruited use from 83 to 99 g. Summing up the results of studying the collection of newly created lines, we can highlight the lines 162d, 168v, 175b, KP11 that are potentially promising for use in hybrids. The selections showed that large-fruited lines can be obtained from large-fruited varieties, self-pollination of large-fruited hybrids and crossing lines with hybrids and varieties. Self-pollination and selection of large-fruited lines in several generations does not provide the necessary variability for positive changes in selections. The result of the selection by weight of 1000 seeds in the offspring from crosses and from populations creates opportunities for new large-seeds sunflower.

scholarly journals Disclosing the Nutritional Quality Diversity of Portuguese Common Beans—The Missing Link for Their Effective Use in Protein Quality Breeding Programs

Agronomy ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 221
Author(s):  
Elsa Mecha ◽  
Sofia Natalello ◽  
Bruna Carbas ◽  
Andreia Bento da Silva ◽  
Susana T. Leitão ◽  
...  
Keyword(s):  
Heat Stress ◽  
Amino Acid ◽  
Nutritional Quality ◽  
Dietary Habits ◽  
Protein Quality ◽  
Trypsin Inhibitor Activity ◽  
Environment Interaction ◽  
Individual Amino Acid ◽  
Common Beans ◽  
Breeding Programs

The common bean (Phaseolus vulgaris L.) represents a sustainable and affordable source of protein, namely, to populations with vegetarian dietary habits. Despite the national germplasm genetic diversity, little is known about the Portuguese accessions’ nutritional and protein quality, leading to their underuse in breeding programs. To fill this gap, a representative collection (106 accessions) was cropped under two contrasting environments (traditional versus heat stress) and evaluated in terms of nutritional quality by near-infrared spectroscopy. Protein quality was assessed, under the stressful environment, considering the individual amino acid contents and the activity of trypsin inhibitors through mass spectrometry (LC-MS/MS) and spectrophotometry, respectively. On top of strong genotypic control, the nutritional composition (protein, fat, fiber, moisture and ash) was also highly influenced by the environment and by genotype × environment interaction, with a clear nutritional quality ranking change for the accessions in heat stress conditions. Classified into three clusters, the accessions from the cluster with the highest individual amino acid and protein contents also showed higher trypsin inhibitor activity (TIA). Since different levels of TIA had no translation into contrasting protein digestibility, breeders focusing on common beans’ protein quality improvement, especially under challenging warming climate conditions, may take advantage of this group of accessions.

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