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991.
Fabieli Loise Braga Feitosa Bianca Ferreira Olivieri Carolyn Aboujaoude Angélica Simone Cravo Pereira Marcos Vinicius Antunes de Lemos Hermenegildo Lucas Justino Chiaia Mariana Piatto Berton Elisa Peripolli Adrielle Matias Ferrinho Lenise Freitas Mueller Mônica Roberta Mazalli Lucia Galvão de Albuquerque Henrique Nunes de Oliveira Humberto Tonhati Rafael Espigolan Rafael Lara Tonussi Rafael Medeiros de Oliveira Silva Daniel Gustavo Mansan Gordo Ana Fabrícia Braga Magalhães Ignacio Aguilar Fernando Baldi 《Journal of applied genetics》2017,58(1):123-132
The objective of this study was to estimate the genetic–quantitative relationships between the beef fatty acid profile with the carcass and meat traits of Nellore cattle. A total of 1826 bulls finished in feedlot conditions and slaughtered at 24 months of age on average were used. The following carcass and meat traits were analysed: subcutaneous fat thickness (BF), shear force (SF) and total intramuscular fat (IMF). The fatty acid (FA) profile of the Longissimus thoracis samples was determined. Twenty-five FAs (18 individuals and seven groups of FAs) were selected due to their importance for human health. The animals were genotyped with the BovineHD BeadChip and, after quality control for single nucleotide polymorphisms (SNPs), only 470,007 SNPs from 1556 samples remained. The model included the random genetic additive direct effect, the fixed effect of the contemporary group and the animal’s slaughter age as a covariable. The (co)variances and genetic parameters were estimated using the REML method, considering an animal model (single-step GBLUP). A total of 25 multi-trait analyses, with four traits, were performed considering SF, BF and IMF plus each individual FA. The heritability estimates for individual saturated fatty acids (SFA) varied from 0.06 to 0.65, for monounsaturated fatty acids (MUFA) it varied from 0.02 to 0.14 and for polyunsaturated fatty acids (PUFA) it ranged from 0.05 to 0.68. The heritability estimates for Omega 3, Omega 6, SFA, MUFA and PUFA sum were low to moderate, varying from 0.09 to 0.20. The carcass and meat traits, SF (0.06) and IMF (0.07), had low heritability estimates, while BF (0.17) was moderate. The genetic correlation estimates between SFA sum, MUFA sum and PUFA sum with BF were 0.04, 0.64 and ?0.41, respectively. The genetic correlation estimates between SFA sum, MUFA sum and PUFA sum with SF were 0.29, ?0.06 and ?0.04, respectively. The genetic correlation estimates between SFA sum, MUFA sum and PUFA sum with IMF were 0.24, 0.90 and ?0.67, respectively. The selection to improve meat tenderness in Nellore cattle should not change the fatty acid composition in beef, so it is possible to improve this attribute without affecting the nutritional beef quality in zebu breeds. However, selection for increased deposition of subcutaneous fat thickness and especially the percentage of intramuscular fat should lead to changes in the fat composition, highlighting a genetic antagonism between meat nutritional value and acceptability by the consumer. 相似文献
992.
Caught in the web: Spider web architecture affects prey specialization and spider–prey stoichiometric relationships 下载免费PDF全文
Lorraine Ludwig Matthew A. Barbour Jennifer Guevara Leticia Avilés Angélica L. González 《Ecology and evolution》2018,8(13):6449-6462
Quantitative approaches to predator–prey interactions are central to understanding the structure of food webs and their dynamics. Different predatory strategies may influence the occurrence and strength of trophic interactions likely affecting the rates and magnitudes of energy and nutrient transfer between trophic levels and stoichiometry of predator–prey interactions. Here, we used spider–prey interactions as a model system to investigate whether different spider web architectures—orb, tangle, and sheet‐tangle—affect the composition and diet breadth of spiders and whether these, in turn, influence stoichiometric relationships between spiders and their prey. Our results showed that web architecture partially affects the richness and composition of the prey captured by spiders. Tangle‐web spiders were specialists, capturing a restricted subset of the prey community (primarily Diptera), whereas orb and sheet‐tangle web spiders were generalists, capturing a broader range of prey types. We also observed elemental imbalances between spiders and their prey. In general, spiders had higher requirements for both nitrogen (N) and phosphorus (P) than those provided by their prey even after accounting for prey biomass. Larger P imbalances for tangle‐web spiders than for orb and sheet‐tangle web spiders suggest that trophic specialization may impose strong elemental constraints for these predators unless they display behavioral or physiological mechanisms to cope with nutrient limitation. Our findings suggest that integrating quantitative analysis of species interactions with elemental stoichiometry can help to better understand the occurrence of stoichiometric imbalances in predator–prey interactions. 相似文献
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Neil C. Glynn Chris Laborde R. Wayne Davidson Mike S. Irey Barry Glaz Angélique D’Hont Jack C. Comstock 《Molecular breeding : new strategies in plant improvement》2013,31(2):323-331
Brown rust, caused by Puccinia melanocephala, has had devastating effects on sugarcane (Saccharum spp.) breeding programs and commercial production. The discovery of Bru1, a major gene conferring resistance to brown rust, represented a substantial breakthrough. Markers for Bru1 are the first available for sugarcane molecular breeding. The contribution of Bru1 towards brown rust resistance in the Canal Point (CP) sugarcane breeding program was determined as a means of directing future breeding strategies. Bru1 was detected in 285 of 1,072 (27 %) clones used for crossing; this germplasm represents the genetic base for cultivar development in Florida. The frequency of Bru1 was greatest in CP clones (42 %) and lowest among Louisiana clones (6 %). Bru1 was not detected in clones with year assignments before 1953. However, Bru1 frequency increased from 15 % (assignments 1975–1985) to 47 % in the current decade. The increase coincided with the introduction of brown rust to Florida. Bru1 was detected in 155 (32 %) of 485 parental clones tested for brown rust susceptibility at two field locations. Of clones classed resistant to brown rust, 154 (59 %) contained Bru1, yet none of 100 susceptible clones contained the gene. Bru1 was detected in 667 (44 %) clones in the second clonal stage of selection, 87 % of which were free of brown rust symptoms. Bru1 is the predominant source of resistance in the Florida sugarcane genetic base. Efforts to identify and integrate new brown rust resistance genes must be pursued to minimize risks associated with a future breakdown in major gene resistance provided by Bru1. 相似文献
996.
Mutational analysis of the phage T4 morphogenetic 31 gene, whose product interacts with the Escherichia coli GroEL protein 总被引:4,自引:0,他引:4
The phage T4 morphogenetic gene 31 has been sequenced. Its deduced gene product is a polypeptide of 111 aa, with a predicted Mr of 12064 and a pI of 4.88. The proof that the assigned open reading frame (ORF) encodes Gp31 rests on the sequencing of two known gene 31 amber mutations, amN54 and NG71, demonstrating that these mutations result in translational termination within the assigned ORF. Furthermore, the sequencing of four different T4 epsilon mutations, isolated on the basis of allowing the phage to propagate on Escherichia coli groEL- hosts, showed that they are either missense mutations or 3-bp deletions in the gene 31 reading frame. The sequencing of neighboring DNA revealed the presence of five other ORFs, one of which overlaps gene 31 substantially, but in the opposite orientation. 相似文献
997.
Thirty patients receiving haemodialysis, including two who had undergone bilateral nephrectomy, showed significant increases (p less than 0.001) in packed cell volume, haemoglobin concentration, and reticulocyte count during an episode of viral or toxic liver cytolysis. In 19 cases the episode lasted a mean of 5.0 +/- SD 2.9 months and was accompanied by improved haematological values for a mean of 12.0 +/- 6.0 weeks. Of the remaining patients, in whom the episode lasted a mean of 8.0 +/- 3.5 months (p less than 0.02), seven showed continued improvement a mean of 30.0 +/- 16.0 weeks after cytolysis. In eight patients in this group there was an apparent correlation between persistently increased haemoglobin concentrations and biopsy evidence of chronic hepatitis. The findings suggest that the reduction in anaemia resulted from enhanced red-cell production mediated by secretion of erythropoietin from regenerating liver cells. If confirmed this might have important implications for the treatment of anaemia in chronic renal insufficiency. 相似文献
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999.
Hamon C Baranger A Coyne CJ McGee RJ Le Goff I L'anthoëne V Esnault R Rivière JP Klein A Mangin P McPhee KE Roux-Duparque M Porter L Miteul H Lesné A Morin G Onfroy C Moussart A Tivoli B Delourme R Pilet-Nayel ML 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2011,123(2):261-281
Partial resistances, often controlled by quantitative trait loci (QTL), are considered to be more durable than monogenic resistances. Therefore, a precursor to developing efficient breeding programs for polygenic resistance to pathogens should be a greater understanding of genetic diversity and stability of resistance QTL in plants. In this study, we deciphered the diversity and stability of resistance QTL to Aphanomyces euteiches in pea towards pathogen variability, environments and scoring criteria, from two new sources of partial resistance (PI?180693 and 552), effective in French and USA infested fields. Two mapping populations of 178 recombinant inbred lines each, derived from crosses between 552 or PI 180693 (partially resistant) and Baccara (susceptible), were used to identify QTL for Aphanomyces root rot resistance in controlled and in multiple French and USA field conditions using several resistance criteria. We identified a total of 135 additive-effect QTL corresponding to 23 genomic regions and 13 significant epistatic interactions associated with partial resistance to A.?euteiches in pea. Among the 23 additive-effect genomic regions identified, five were consistently detected, and showed highly stable effects towards A.?euteiches strains, environments, resistance criteria, condition tests and RIL populations studied. These results confirm the complexity of inheritance of partial resistance to A.?euteiches in pea and provide good bases for the choice of consistent QTL to use in marker-assisted selection schemes to increase current levels of resistance to A.?euteiches in pea breeding programs. 相似文献
1000.
Shark fishery is one of the most important activities in the Mexican Pacific coast, nevertheless, there is few data available about the specific captures done by the fleet along the coast. This study describes fishery biology aspects of the shark species catched by the semi-industrial long-line fleet of Manzanillo. Monthly samplings were made on board of these vessels during an annual period from April 2006 to April 2007. Captured species composition (n = 1 962 organisms) was represented by nine species. The one that sustains this fishery was Carcharhinus falciformis (88.12%), followed by Prionace glauca (8.21%). Low frequency species were represented by Sphyrna zygaena (1.78%), Alopias pelagicus (0.82%), Carcharhinus longimanus (0.45%). Furthermore, rare species were Alopias superciliosus (0.35%), Carcharhinus leucas (0.1%), Carcharhinus limbatus (0.1%) and Isurus oxyrinchus (0.05%). Fishery activity affected principally (60-92.70%) young males of C. falciformis, S. zygaena, C. longimanus and I. oxyrinchus; adult males (56-75%) of A. pelagicus, A. superciliosus, and C. limbatus; for P. glauca there were primarily female adults. For all the species found, females showed the bigger sizes when compared to males (with the exception of S. zygaena, that showed sexual dimorphism). Considering the lineal regressions made between precaudal length and total length, and, fork length and total length for C. falciformis, P. glauca, S. zygaena and A. pelagicus, the determination coefficients (r2) showed that both lengths can be useful to obtain the total length of fish with some damage or absence of its caudal fin. The estimated fecundity for C. falciformis was of 3-7 offspring/female of 30-45 cm LT (average of 40.57 +/- 2.03 cm LT); and for P. glauca 5-52 offspring/female of 5-18.6 cm LT (average of 11.61 +/- 0.21 cm LT). In the case of C. longimanus only one female was captured with a total of eight embryos, with an average of 45 cm LT each; for this reason we assumed that the fishery areas do not coincide with the nursery oness for this species. According to the information obtained, we concluded that C. falciformis has a concurrent cycle and P. glauca a consecutive biannual one. 相似文献