Josep Reixach

Publications (3)5.47 Total impact

• Source

  Available from: Joan Tibau

  Article: Factors affecting longevity in maternal Duroc swine lines

  Joaquim Tarrés, Joan Tibau, Jesú S Piedrafita, Emma Fàbrega, Josep Reixach
  [show abstract] [hide abstract]
  ABSTRACT: A competing risks approach was used to evaluate the influence of several pre-farrowing factors on risk of culling due to different causes in Duroc swine, these having low fertility, low productivity, lameness and mortality. Culling due to low fertility increased for average daily gains during the growth test lower than 585 g/day, whereas culling due to low productivity and mortality increased with low levels of backfat thickness at the end of the growth test. Lesser loin depths at first farrowing reduced culling due to low productivity but increased culling due to lameness. Furthermore, a higher average daily gain from the end of the growth test to first mating increased culling by all causes. A complementary analysis was carried out to evaluate the influence of these factors on risk of culling without taking into account the specific reason of failure. In this second analysis, the factors were included as time-dependent covariates whose relative importance changed throughout the sows' productive life. Expected survival functions and replacement rates have been calculated in different hypothetical situations in order to determine the optimal animal body type at first farrowing to maximise longevity, which under our production conditions is independent of average daily gain from birth until the end of the growth test, but from the end of the growth test to first mating average daily gain should not be over 485 g/day; backfat thickness should be more than 16 mm at the end of the growth test and maintain this level until the first parturition without exceeding 19 mm; loin depth should be kept below 45 mm at first farrowing. D 2005 Elsevier B.V. All rights reserved.
  Riudarenes. ;
• Source

  Available from: Oscar Ramírez

  Article: Mapping of quantitative trait loci for cholesterol, LDL, HDL, and triglyceride serum concentrations in pigs.

  David Gallardo, Ramona N Pena, Marcel Amills, Luis Varona, Oscar Ramírez, Josep Reixach, Isabel Díaz, Joan Tibau, Joaquim Soler, Josep M Prat-Cuffi, José L Noguera, Raquel Quintanilla
  [show abstract] [hide abstract]
  ABSTRACT: The fine mapping of polymorphisms influencing cholesterol (CT), triglyceride (TG), and lipoprotein serum levels in human and mouse has provided a wealth of knowledge about the complex genetic architecture of these traits. The extension of these genetic analyses to pigs would be of utmost importance since they constitute a valuable biological and clinical model for the study of coronary artery disease and myocardial infarction. In the present work, we performed a whole genome scan for serum lipid traits in a half-sib Duroc pig population of 350 individuals. Phenotypic registers included total CT, TG, and low (LDL)- and high (HDL)-density lipoprotein serum concentrations at 45 and 190 days of age. This approach allowed us to identify two genomewide significant quantitative trait loci (QTL) for HDL-to-LDL ratio at 45 days (SSC6, 84 cM) and for TG at 190 days (SSC4, 23 cM) as well as a number of chromosomewide significant QTL. The comparison of QTL locations at 45 and 190 days revealed a notable lack of concordance at these two time points, suggesting that the effects of these QTL are age specific. Moreover, we have observed a considerable level of correspondence among the locations of the most significant porcine lipid QTL and those identified in humans. This finding might suggest that, in mammals, diverse polymorphisms located in a common set of genes are involved in the genetic variation of serum lipid levels.
  Physiological Genomics 10/2008; 35(3):199-209. · 2.73 Impact Factor
• Article: Association of CA repeat polymorphism at intron 1 of insulin-like growth factor (IGF-I) gene with circulating IGF-I concentration, growth, and fatness in swine.

  Joan Estany, Marc Tor, Daniel Villalba, Lluís Bosch, David Gallardo, Neus Jiménez, Laura Altet, Jose L Noguera, Josep Reixach, Marcel Amills, Armand Sánchez
  [show abstract] [hide abstract]
  ABSTRACT: Evidence is accumulating that intronic polymorphic cytosine-adenosine (CA) repeats may play a role in gene expression. In this work, we investigated whether a polymorphic CA short tandem repeat (STR) located at the first intron of the pig insulin-like growth factor I (IGF-I) gene influences plasma IGF-I concentration in pigs as well as phenotypic variation in growth and fatness traits. We measured plasma IGF-I levels at one to four time points from 35 to 215 days of age in 340 performance-tested Landrace and Duroc pigs previously genotyped for the IGF-I STR. Data were analyzed within breed with a linear mixed model with the number of CA repeats as a covariate. At least five alleles were segregating in each breed, differing in one to seven repeats. The results showed that in each breed, circulating IGF-I at 160 days of age increased with the length of the shortest allele, accounting for an average trend of 4.38 +/- 1.28 ng/ml of IGF-I per additional repeat (P = 0.001). Longer repeats were associated with early growth in Landrace boars (1.92 +/- 0.92 kg per CA at 160 days; P = 0.038) and with back fat thickness (-0.57 +/- 0.20 mm per CA; P = 0.005) and lean content (7.52 +/- 3.00 g/kg per CA at 105 kg; P = 0.013) adjusted for carcass weight in Duroc barrows, as expected from the effect of circulating IGF-I on these traits. The consistency of the results across populations supports the hypothesis that the length of the CA repeats at intron 1 of the IGF-I gene is associated with circulating IGF-I levels, and that this effect is not neutral with respect to growth and fatness.
  Physiological Genomics 11/2007; 31(2):236-43. · 2.73 Impact Factor