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Fate of beta-glucan, polyphenols and lipophilic compounds in baked crackers fortified with different barley-milled fractionsFour types of crackers were prepared, whereby wheat flour was substituted with different percentages of barley flour and bran. These formulations were compared to a 100% wheat flour (control) cracker with respect to β-glucan, polyphenols and lipophilic bioactives. Incorporation of barley fractions enriched the β-glucan, and phenolic content, as well as in vitro antioxidant capacities of the crackers. However, some polyphenols including procyanidin C and ferulic acid could not be detected in the crackers owing to the probable degradation of these compounds during baking. The β-glucan, flavanols (catechin and procyanidin B), as well as fatty acids and sterols were least affected; while the α-tocotrienols showed degradation following the baking process. Overall, barley fractions can serve as valued ingredients for enhancing the health-salutary components of fortified crackers or the products thereof.
Effect of Exposure to Seminal Plasma Through Natural Mating in Cattle on Conceptus Length and Gene ExpressionA growing body of evidence suggests that paternal factors have an impact on offspring development. These studies have been mainly carried out in mice, where seminal plasma (SP) has been shown to regulate endometrial gene expression and impact embryo development and subsequent offspring health. In cattle, infusion of SP into the uterus also induces changes in endometrial gene expression, however, evidence for an effect of SP on early embryo development is lacking. In addition, during natural mating, the bull ejaculates in the vagina; hence, it is not clear whether any SP reaches the uterus in this species. Thus, the aim of the present study was to determine whether SP exposure leads to improved early embryo survival and developmental rates in cattle. To this end, Day 7 in vitro produced blastocysts were transferred to heifers (12–15 per heifer) previously mated to vasectomized bulls (n = 13 heifers) or left unmated (n = 12 heifers; control). At Day 14, heifers were slaughtered, and conceptuses were recovered to assess size, morphology and expression of candidate genes involved in different developmental pathways. Additionally, CL volume at Day 7, and weight and volume of CL at Day 14 were recorded. No effect of SP on CL volume and weight not on conceptus recovery rate was observed. However, filamentous conceptuses recovered from SP-exposed heifers were longer in comparison to the control group and differed in expression of CALM1, CITED1, DLD, HNRNPDL, PTGS2, and TGFB3. In conclusion, data indicate that female exposure to SP during natural mating can affect conceptus development in cattle. This is probably achieved through modulation of the female reproductive environment at the time of mating. Keywords: seminal plasma, embryo development, corpus luteum
Genomic Regions Associated With Gestation Length Detected Using Whole-Genome Sequence Data Differ Between Dairy and Beef CattleWhile many association studies exist that have attempted to relate genomic markers to phenotypic performance in cattle, very few have considered gestation length as a phenotype, and of those that did, none used whole genome sequence data from multiple breeds. The objective of the present study was therefore to relate imputed whole genome sequence data to estimated breeding values for gestation length using 22,566 sires (representing 2,262,706 progeny) of multiple breeds [Angus (AA), Charolais (CH), Holstein-Friesian (HF), and Limousin (LM)]. The associations were undertaken within breed using linear mixed models that accounted for genomic relatedness among sires; a separate association analysis was undertaken with all breeds analysed together but with breed included as a fixed effect in the model. Furthermore, the genome was divided into 500 kb segments and whether or not segments harboured a single nucleotide polymorphism (SNP) with a P ≤ 1 × 10-4 common to different combinations of breeds was determined. Putative quantitative trait loci (QTL) regions associated with gestation length were detected in all breeds; significant associations with gestation length were only detected in the HF population and in the across-breed analysis of all 22,566 sires. Twenty-five SNPs were significantly associated (P ≤ 5 × 10-8) with gestation length in the HF population. Of the 25 significant SNPs, 18 were located within three QTLs on Bos taurus autosome number (BTA) 18, six were in two QTL on BTA19, and one was located within a QTL on BTA7. The strongest association was rs381577268, a downstream variant of ZNF613 located within a QTL spanning from 58.06 to 58.19 Mb on BTA18; it accounted for 1.37% of the genetic variance in gestation length. Overall there were 11 HF animals within the edited dataset that were homozygous for the T allele at rs381577268 and these had a 3.3 day longer (P < 0.0001) estimated breeding value (EBV) for gestation length than the heterozygous animals and a 4.7 day longer (P < 0.0001) EBV for gestation length than the homozygous CC animals. The majority of the 500 kb windows harboring a SNP with a P ≤ 1 × 10-4 were unique to a single breed and no window was shared among all four breeds for gestation length, suggesting any QTLs identified are breed-specific associations.
Expression, purification and antimicrobial activity of recombinant pediocin PA-1 M31L, a PA-1 derivative with enhanced stabilityPediocin, the prototypical class IIa bacteriocin, is an efficient antilisterial molecule. Loss of pediocin PA-1 activity is attributed to methionine oxidation at position 31 and this can be overcome by substituting methionine for leucine (pediocin M31L). The aim of this study was to produce pediocin M31L with enhanced stability by recombinant expression in E. coli cells.