The use of genomic information can enhance the efficiency of conservation programs

• The development of genomic tools allows for more accurate estimates of genetic relationships between animals (genomic coancestry coefficients) than those obtained with pedigree data (pedigree-based coancestry coefficients) and thus permit better management of genetic diversity. • There are different issues relevant to conservation programs that could benefit from the use of genomic data. These include establishing synthetic ex situ populations, maintaining genetic diversity, preserving original genetic structures, and eliminating exogenous genetic information. The use of dense panels of single-nucleotide polymorphism (SNPs) in strategies proposed to deal with all these issues improves the general performance of conservation programs in both farm and wild animal populations. © Fernández, Toro, Gómez-Romano, and Villanueva

Pyridines from azabicyclo[3.2.0]hept-2-en-4-ones through a proposed azacyclopentadienone

Pyridines have been formed by heating azabicyclo[3.2.0]hept-2-en-4-ones in toluene. The generation of a 3-azacyclopentadienone intermediate via a [2+2]-cycloreversion is proposed as the key step. A Diels-Alder reaction of a styrene, extrusion of carbon monoxide and loss of hydrogen then gives the pyridine. The process parallels the well-known synthesis of benzenes from cyclopentadienones. The azabicyclo[3.2.0]hept-2-en-4-ones were synthesized from the reaction between readily available cyclopropenones and 1-azetines, in which the cyclopropenones behave as all-carbon 1,3-dipolar equivalents

The use of coancestry based on shared segments for maintaining genetic diversity

We have evaluated the use of genomic coancestry coefficients based on shared segments for the maintenance of genetic diversity through optimal contributions methodology for populations of three different Austrian cattle breeds. This coancestry measure has been compared with the genomic coancestry coefficient calculated on a SNP-by-SNP basis and with pedigree-based coancestry. The regressions of the shared segments coancestry on the other two coefficients suggest that the former mainly reflect Identity By Descent but with the advantage over pedigree-based coancestry of providing the realized Identity By Descent rather than an expectation. The effective population size estimated from the rate of coancestry based on shared segments was very similar to those obtained with the other coefficients and of small magnitude (from 26.24 to 111.90). This result highlights the importance of implementing active management strategies to control the increase of inbreeding and the loss of genetic diversity in livestock breeds, even when the population size is reasonably large. One problem for the implementation of coancestry based on shared segments is the need of estimating the gametic phases of the SNPs which, given the techniques used to obtain the genotypes, are a priori unknown. This study shows, through computer simulations, that using estimates of gametic phases for computing coancestry based on shared segments does not lead to a significant loss in the diversity maintained. This has been shown to be true even when the size of the population is very small as it is usually the case in populations subjected to conservation programmes. © 2016 Blackwell Verlag GmbH

Genomic study for maternal related traits in Santa Inês sheep breed

The aim of this study was to estimate variance components and to identify genomic regions and pathways associated with maternal related traits in Santa Inês sheep breed adapted to tropical climate. Phenotypic records for maternal efficiency (ME), metabolic maternal efficiency (MME), twin lambing (TL), adult weight (AW), metabolic adult weight (MAW), and body condition score (BCS) from 1333 ewes from Santa Inês breed were used. A total of 576 animals were genotyped with the Ovine SNP12k BeadChip (Illumina, Inc.), that contains 12,785 bialleleic SNP markers. The variance components were estimated using a single trait animal model by single step genomic BLUP procedure. For AW, MAW, BCS, ME, MME and TL the mean values were 50.30 (±9.76), 19.2 (±2.33), 2.76 (±0.72), 34.6 (±15.95), 91.8 (±42.52), and 1.27 (±0.44), respectively. The heritabilities estimated were moderate for AW (0.32) and MAW (0.33) and low for BCS (0.04), ME (0.07), MME (0.08), and TL (0.10). A total of 7, 8, 13, 16, 19, and 09 candidate regions for ME, MME, TL, AW, MAW and BCS traits were identified, respectively. AW and MAW had a total of 15 regions in common, while AW and BCS had a common region on chromosome 21. ME and MME had six candidate regions in common, and TL had no common regions with any other features. The maternal indicator traits have genetic variability to respond to selection in Santa Inês breed, and it would be expected higher genetic gain for ewe adult weight when compared to the others studied traits. Several candidate regions related to growth, reproduction, lactation and enviromental adaptability were identified in this study. These candidate regions would give support to identify and select animals with higher maternal efficiency and fitness, and consequently, increase the productivity of Santa Inês sheep. Moreover, the results of this study should help to understand the genetic and physiologic mechanism associated with maternal related traits in Santa Inês breed