Embrapa Rondonia

Porto Velho, Brazil

Embrapa Rondonia

Porto Velho, Brazil

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Akbar H.,Urbana University | Schmitt E.,Embrapa Rondonia | Ballou M.A.,Texas Tech University | Correa M.N.,Federal University of Pelotas | And 2 more authors.
Gene Regulation and Systems Biology | Year: 2013

Polyunsaturated (PUFA) long-chain fatty acids (LCFAs) are more potent in eliciting molecular and tissue functional changes in monogastrics than saturated LCFA. From -21 through 10 days relative to parturition dairy cows were fed no supplemental LCFA (control), saturated LCFA (SFAT; mainly 16:0 and 18:0), or fish oil (FISH; high-PUFA). Twenty-seven genes were measured via quantitative RT-PCR in liver tissue on day -14 and day 10. Expression of nuclear receptor co-activators (CARM1, MED1), LCFA metabolism (ACSL1, SCD, ACOX1), and inflammation (IL6, TBK1, IKBKE) genes was lower with SFAT than control on day -14. Expression of SCD, however, was markedly lower with FISH than control or SFAT on both -14 and 10 days. FISH led to further decreases in expression on day 10 of LCFA metabolism (CD36, PLIN2, ACSL1, ACOX1), intracellular energy (UCP2, STK11, PRKAA1), de novo cholesterol synthesis (SREBF2), inflammation (IL6, TBK1, IKBKE), and nuclear receptor signaling genes (PPARD, MED1, NRIP1). No change in expression was observed for PPARA and RXRA. The increase of DGAT2, PLIN2, ACSL1, and ACOX1 on day 10 versus -14 in cows fed SFAT suggested upregulation of both beta-oxidation and lipid droplet (LD) formation. However, liver triacylglycerol concentration was similar among treatments. The hepatokine FGF21 and the gluconeogenic genes PC and PCK1 increased markedly on day 10 versus -14 only in controls. At the levels supplemented, the change in the profile of metabolic genes after parturition in cows fed saturated fat suggested a greater capacity for uptake of fatty acids and intracellular handling without excessive storage of LD. © the author(s), publisher and licensee Libertas Academica Ltd.

Ferrao L.F.V.,Federal University of Viçosa | Caixeta E.T.,Federal University of Viçosa | Souza F.F.,Embrapa Rondonia | Zambolim E.M.,Federal University of Viçosa | And 3 more authors.
Plant Systematics and Evolution | Year: 2013

The genetic variability characterization of the accessions of the germplasm collection, using molecular markers, is being applied as a complementary strategy to the traditional approaches to redefine the plant genetic resources. In this study, we compared the informativeness and efficiency of the molecular markers RAPD, AFLP and SSR in the analysis of 94 accessions of Coffea canephora germplasm held by the breeding program of the Brazilian Agricultural Research Corporation (Embrapa), Rondônia State, Brazil. For this, we considered the marker's discriminatory power and level of polymorphism detected and also the genetic relationships and clustering (dendrogram) analysis. The RAPD marker yielded low-quality data and problems in the discrimination of some accessions, being less recommended for genetic studies of C. canephora. The SSRs had a higher level of information content and yielded high-quality data, while AFLP was the most efficient marker system because of the simultaneous detection of abundant polymorphism markers per few reactions. Our results indicate that AFLP and SSR, allies to the intrinsic characteristics of each technique, are the most suitable molecular markers for genetic studies of C. canephora. However, the choice of AFLP or SSR in the species characterization should be made in agreement with some characteristics that are discussed in this work. © 2012 Springer-Verlag Wien.

Laviola B.G.,Embrapa Agroenergy | Oliveira A.M.C.E.,Federal University of Viçosa | Bhering L.L.,Federal University of Viçosa | Alves A.A.,Embrapa Agroenergy | And 3 more authors.
Industrial Crops and Products | Year: 2013

The aim of this study was to estimate the repeatability coefficient of grain production in Jatropha, the minimum number of measurements needed to reliably predict the genetic value of selected families, and to determine the cumulative genetic gains when considering the selection of the best families based on different number of measurements. The experiment was conducted with 175 accessions (half-siblings progenies derived from selected plants in the field) that compose part of a germplasm collection. Such bank was established in a randomized block design with two blocks. In each block a given accession was represented in a 5plant/plot scheme (half-siblings). For the analysis, yield data obtained in the years of 2009-2012 were considered. The results of this study indicate that the repeatability coefficient of grain production in Jatropha is low (0.37), but comparable to other perennial species, and that to achieve reliabilities of 70 and 80% in the prediction of breeding values of selected families, 4 and 7 years of evaluation, respectively, are needed. The results of this study also indicate that the efficiency of early selection seems to be small in Jatropha since the coincidence rate of selected genotypes at early age (1 or 2 years of evaluation) and genotypes selected in adult age (4 years assessment) is small (17-23%). Finally, taking into account the repeatability coefficients and coefficients of determination, in a hypothetical period of 21 years (which is equivalent to three selection cycles using seven consecutive measurements - R2=80%), this paper demonstrates that higher cumulative genetic gains can be obtained (159% over 108%) by relaxing the degree of certainty in predicting the best families (R2=65% instead of R2=80%), since it makes possible to perform a greater number of selection cycles in the same period (7 cycles instead of 4). © 2013 Elsevier B.V.

PubMed | Embrapa Suinos e Aves, Embrapa Pecuaria Sudeste, University Estadual Julio Of Mesquita Filho, Embrapa Rondonia and Federal University of São Carlos
Type: Journal Article | Journal: Ticks and tick-borne diseases | Year: 2016

The levels of infection by Babesia bovis and Babesia bigemina were estimated by absolute quantification through the quantitative PCR technique (qPCR). Fifty-one contemporaneous Angus cattle were evaluated on two occasions. The number of standard female Rhipicephalus microplus ticks present on the left side of the body was counted and blood samples were drawn from the tail vein into tubes containing the anticoagulant EDTA. The blood samples were submitted to DNA extraction and used to quantify the number of copies (NC) of DNA from B. bovis and B. bigemina by qPCR. The data on tick count and number of DNA copies were transformed for normalization and analyzed by a mixed model method. A multivariate model with repeated measures of the same animal, including the effects of collection, parasite species and their interaction, was used. The repeatability values were obtained from the matrix of (co)variances and were expressed for each species. The correlations between the counts of different species on the same animal, in the same collection or different collections, were also estimated. The results showed the qPCR could distinguish the two between infection by the two Babesia species. Infection levels by B. bovis and B. bigemina were detected in 100% and 98% of the animals, respectively. Significant differences were found (P<0.05) between the NC of the two Babesia species, B. bovis 1.490.07 vs. B. bigemina 0.820.06. Low repeatabilities were found for the counts of R. microplus and NC of B. bovis and B. bigemina: 0.05, 0.10 and 0.02, respectively. The correlations between R. microplus count and NC of B. bovis and B. bigemina were both very near zero. However, an association was observed between the NC of the two species, with a correlation coefficient of 0.30 for measures from the same collection. The absence of associations between the quantity of DNA from B. bovis and B. bigemina and the tick counts suggests that the variation of parasitemia by the hemoparasites did not depend on the tick infestation levels at the moment of each collection. The repeatability values estimated indicate that under the study conditions, the variations in the tick infestation levels and of parasitemia by B. bovis and B. bigemina depend more on factors related to each collection than on intrinsic factors of the animal.

PubMed | Embrapa Rondonia, Federal University of Viçosa and Embrapa Agroenergia
Type: Journal Article | Journal: Genetics and molecular research : GMR | Year: 2016

The aim of this study was to estimate genetic parameters via mixed models and simultaneously to select Jatropha progenies grown in three regions of Brazil that meet high adaptability and stability. From a previous phenotypic selection, three progeny tests were installed in 2008 in the municipalities of Planaltina-DF (Midwest), Nova Porteirinha-MG (Southeast), and Pelotas-RS (South). We evaluated 18 families of half-sib in a randomized block design with three replications. Genetic parameters were estimated using restricted maximum likelihood/best linear unbiased prediction. Selection was based on the harmonic mean of the relative performance of genetic values method in three strategies considering: 1) performance in each environment (with interaction effect); 2) performance in each environment (with interaction effect); and 3) simultaneous selection for grain yield, stability and adaptability. Accuracy obtained (91%) reveals excellent experimental quality and consequently safety and credibility in the selection of superior progenies for grain yield. The gain with the selection of the best five progenies was more than 20%, regardless of the selection strategy. Thus, based on the three selection strategies used in this study, the progenies 4, 11, and 3 (selected in all environments and the mean environment and by adaptability and phenotypic stability methods) are the most suitable for growing in the three regions evaluated.

Rocha R.B.,Embrapa Rondonia | Ramalho A.R.,Embrapa Rondonia | Teixeira A.L.,Embrapa Rondonia | Laviola B.G.,Embrapa Agroenergia | And 2 more authors.
Pesquisa Agropecuaria Brasileira | Year: 2012

The objective of this work was to estimate the genetic parameters of physic nut (Jatropha curcas) grain quality traits and to quantify the genetic progress with selection. Seed oil content, and seed, kernel, and shell weights of 120 plants, randomly selected in a commercial planting, were evaluated at 36 and 48 months. Genetic progress was quantified by the evaluation of direct gains and by the use of selection indexes. The genotype x measurement interaction was significant for all evaluated traits; therefore, there are genotypes with different behavior in the two cropping seasons. The genetic parameters indicated a higher proportion of genotypic variation in the expression of the evaluated traits, and a trend of the genotypes to maintain their genetic superiority over time was observed. The genotype-ideotype selection index resulted in higher genetic gains and promoted a more balanced alteration in the trait means. The direct selection for kernel weight results in genetic gains similar to those obtained with the use of the selection indexes.

Laviola B.G.,EMBRAPA - Empresa Brasileira de Pesquisa Agropecuária | Alves A.A.,EMBRAPA - Empresa Brasileira de Pesquisa Agropecuária | Gurgel F.L.,Embrapa Amazonia Oriental | Rosado T.B.,EMBRAPA - Empresa Brasileira de Pesquisa Agropecuária | And 2 more authors.
Ciencia Rural | Year: 2012

In spite of increasingly widespread interest in planting physic nut, breeding efforts are still in its infancy. In that context, an important resource recently established aiming future breeding efforts was the assembly of a germplasm bank with near 200 accessions. The objective of this study was to estimate genetic parameters, repeatibility coefficients and genetic correlation between seven traits, measured in 110 accessions (half sib families) of this germplasm bank in different stages of development. The results show that higher relative values of additive variance were only found for yield and height, and the existence of low environmental variation (either of temporary or permanent nature) among plots within blocks. Given the high repeatibility values found for all traits, on average three measurements are necessary to predict, accurately and efficiently, the true breeding value of an individual. Based on the results of genetic correlations, breeding effort should initially be use track trees with increased stem diameter, elevated number of branches and canopy volume so as to increase the chances of finding an exceptionally highly productive tree.

Pfeifer L.F.M.,Embrapa Rondonia | Siqueira L.G.B.,Embrapa Gado de Leite | Adams G.P.,University of Saskatchewan | Pierson R.A.,University of Saskatchewan | Singh J.,University of Saskatchewan
Animal Reproduction Science | Year: 2012

The objectives of this study were to: (1) evaluate the feasibility of ultrasonic biomicroscopy (UBM) for imaging ovarian follicles in vivo in cows and heifers, (2) compare the transvaginal to the transrectal approach, (3) compare the number of follicles detected by UBM to conventional ultrasonography (US), and (4) identify cumulus-oocyte-complexes (COC) within follicles by UBM. Mature cows (. n=. 5) and peri-pubertal heifers (. n=. 5) were examined once using conventional B-mode US (Aloka 900) with a 7.5. MHz transrectal, and a 5. MHz transvaginal transducers. A second series of examinations was performed using UBM (Visualsonics Vevo 660) equipped with a 30. MHz transrectal and a 40. MHz transvaginal transducer. A three- to four-fold increase in the number of small follicles (<3. mm) was detected using the transvaginal approach with UBM compared to conventional US in both heifers (32.4. ±. 4.24 compared to 7.2. ±. 1.4; P<. 0.0001) and cows (35.0. ±. 13.8 compared to 10.7. ±. 7.5; P=. 0.0013). However, fewer follicles (all sizes combined) were detected using the transrectal approach with UBM compared to conventional US in both heifers (8.6. ±. 5.6 compared to 17.6. ±. 4.9;P=. 0.02) and cows (5.3. ±. 6.1 compared to 20.3. ±. 7; P=. 0.04). In heifers, COC-like structures were identified in 39 of 202 (19.3%) follicles examined. In conclusion, UBM using a transvaginal approach is feasible and may be used for in vivo assessment of early antral follicles as small as 0.4. mm, and COC within follicles. © 2012 Elsevier B.V.

Khan M.J.,Urbana University | Khan M.J.,COMSATS Institute of Information Technology | Jacometo C.B.,Federal University of Pelotas | Graugnard D.E.,Urbana University | And 4 more authors.
Gene Regulation and Systems Biology | Year: 2014

Hepatic metabolic gene networks were studied in dairy cattle fed control (CON, 1.34 Mcal/kg) or higher energy (overfed (OVE), 1.62 Mcal/kg) diets during the last 45 days of pregnancy. A total of 57 target genes encompassing PPARα-targets/co-regulators, hepatokines, growth hormone (GH)/insulin-like growth factor 1 (IGF-1) axis, lipogenesis, and lipoprotein metabolism were evaluated on -14, 7, 14, and 30 days around parturition. OVE versus CON cows were in more negative energy balance (NEB) postpartum and had greater serum non-esterifed fatty acids (NEFA), β-hydroxybutyrate (BHBA), and liver triacylglycerol (TAG) concentrations. Milk synthesis rate did not differ. Liver from OVE cows responded to postpartal NEB by up-regulating expression of PPARα-targets in the fatty acid oxidation and ketogenesis pathways, along with gluconeogenic genes. Hepatokines (fbroblast growth factor 21 (FGF21), angiopoietin-like 4 (ANGPTL4)) and apolipoprotein A-V (APOA5) were up-regulated postpartum to a greater extent in OVE than CON. OVE led to greater blood insulin prepartum, lower NEFA:insulin, and greater lipogenic gene expression suggesting insulin sensitivity was not impaired. A lack of change in APOB, MTTP, and PNPLA3 coupled with upregulation of PLIN2 postpartum in cows fed OVE contributed to TAG accumulation. Postpartal responses in NEFA and FGF21 with OVE support a role of this hepatokine in diminishing adipose insulin sensitivity. © the authors, publisher and licensee Libertas Academica Limited.

dos Santos M.R.A.,Embrapa Rondonia | Ferreira M.D.G.R.,Embrapa Rondonia | Vania S.,Federal University of Rondônia
Revista Caatinga | Year: 2010

Callus culture has shown a great potential for large-scale multiplication of superior genotypes in a short period of time. The objective of this work was to establish a methodology to induce callus formation in leaf fragments of Coffea canephora Conilon cultivar, to determine the growth curve and to analyze the development of the calli. The growth curve allows to determine the suitable time to subculture the calli in a new medium. The explants were inoculated in 50% MS medium with 10 mg.L-1 thiamine, 1 mg.L-1 pyridoxine, 1 mg.L-1 nicotinic acid, 1 mg.L-1 glycine, inositol 100 mg.L-1, hydrolysed casein 100 mg.L-1 and 400 mg.L-1 malt extract, 20 g.L-1 sucrose, 8 g.L-1 agar, supplemented with IBA (10 μM), 2,4-D (20 μM) and 2iP (10 μM). To determine the growth curve, the calli were weighted up to the 60th day of culture. The callus growth curve presented sigmoidal shape, with five distinct phases. The subculture must be done on the 53th day of culture, aiming at the plant regeneration.

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