Proteomic profile of pre-implantational ovine embryos produced in vivo

The present study was conducted to decipher the proteome of in vivo-produced pre-implantation ovine embryos. Ten locally adapted Morana Nova ewes received hormonal treatment and were inseminated 12 hr after ovulation. Six days later, 54 embryos (morula and blastocyst developmental state) were recovered from eight ewes and pooled to obtain sufficient protein for proteomic analysis. Extracted embryo proteins were analysed by LC-MS/MS, followed by identification based on four database searches (PEAKS, Proteome Discoverer software, SearchGUI software, PepExplorer). Identified proteins were analysed for gene ontology terms, protein clusters and interactions. Genes associated with the ovine embryo proteome were screened for miRNA targets using data sets of TargetScan ( http://www.targetscan.org ) and mIRBase ( http://www.mirbase.org ) servers. There were 667 proteins identified in the ovine embryos. Biological processes of such proteins were mainly related to cellular process and regulation, and molecular functions, to binding and catalytic activity. Analysis of the embryo proteins revealed 49 enriched functional clusters, linked to energy metabolism (TCA cycle, pyruvate and glycolysis metabolism), zona pellucida (ZP), MAPK signalling pathway, tight junction, binding of sperm to ZP, translation, proteasome, cell cycle and calcium/phospholipid binding. Sixteen miRNAs were related to 25 pre-implantation ovine embryo genes, all conserved in human, bovine and ovine species. The interaction network generated by miRNet showed four key miRNAs (hsa-mir-106b-5p; hsa-mir-30-5p; hsa-mir-103a-5p and hsa-mir-106a-5p) with potential interactions with embryo-expressed genes. Functional analysis of the network indicated that miRNAs modulate genes related to cell cycle, regulation of stem cell and embryonic cell differentiation, among others. Retrieved miRNAs also modulate the expression of genes involved in cell signalling pathways, such as MAPK, Wnt, TGF-beta, p53 and Toll-like receptor. The current study describes the first major proteomic profile of 6-day-old ovine embryos produced in vivo, setting a comprehensive foundation for our understanding of embryo physiology in the ovine species.     

The current status and outlook for insecticide,acaricide and anthelmintic resistances across the Australian ruminant livestock industries: assessing the threat these resistances pose to the livestock sector

The Australian ruminant livestock industries are faced with the need to control parasitic infectious diseases that can seriously impact the health of animals. However, increasing levels of resistance to insecticides, anthelmintics and acaricides are substantially reducing the ability to control some of these parasites. Here we review the current situation with regard to chemical resistances in parasites across the various sectors of the Australian ruminant livestock industries and assess the level of threat that these resistances pose to the sustainability of these sectors in the short to long terms. We also look at the extent to which testing for resistance occurs across the various industry sectors, and hence how well-informed these sectors are of the extent of chemical resistance. We examine on-farm management practices, breeding of parasite-resistant animals, and non-chemical therapeutics that may act as short to long term means to reduce the current reliance on chemicals for parasite control. Finally, we look at the balance between the prevalence and magnitude of current resistances and the availability and adoption rates of management, breeding and therapeutic alternatives in order to assess the parasite control outlook for the various industry sectors.     

Cerebellar cortical abiotrophy in Wiltshire sheep

AIM: To investigate the nature of a neurological disease in Wiltshire sheep.

METHODS: Three affected lambs were examined, humanely killed and necropsied. Selected neurological tissues were examined by light and electron microscopy.

RESULTS: Primary neurological lesions were confined to the cerebellum and were characterised by loss of Purkinje cells and the presence of large hypertrophied dendrites of surviving Purkinje cells. These contained stacks of smooth endoplasmic reticulum. There was hyperplasia and cell swelling of Bergmann glia. Mild Wallerian-type degeneration affected white matter in the cerebellum and spinal cord.

CONCLUSION: The cerebellar lesions were of a degenerative and reactive rather than hypoplastic nature. These, and the history, suggest a genetic cause with putative inheritance as an autosomal recessive trait. Accordingly, the disorder is described as a cerebellar abiotrophy.     

Integrated approach for detection of nonculturable cells of Ralstonia solanacearum in asymptomatic Pelargonium spp. cuttings

Ralstonia solanacearum (biovar 2, race 3) is a soil and water-borne pathogen that causes serious diseases in several solanaceous hosts. It can also infect geranium plants, posing an important threat to their culture when latently infected cuttings are imported from countries where the pathogen is endemic. R. solanacearum can be present in very low numbers in asymptomatic geranium cuttings, and/or in a particular stressed physiological state that escapes direct isolation on the solid media usually employed. Consequently, an integrated protocol has been developed to analyze asymptomatic geranium cuttings routinely. The first screening tests include isolation and co-operational-polymerase chain reaction (Co-PCR), based on the simultaneous and co-operational action of three primers from 16S rRNA of R. solanacearum. This method was selected as the most sensitive one, able to detect only 1 cell/ml including nonculturable cells. When isolation is negative but Co-PCR is positive, the bioassay in tomato plants is proposed, since stressed bacterial cells or those present in low numbers that do not grow on solid media can be recovered from inoculated tomato plants and retain pathogenicity. This methodology has been demonstrated to be useful and has allowed us to assess the relevance of the physiological status of bacterial cells and its implications in detection. It also reveals the risk of introducing R. solanacearum through asymptomatic geranium material when relying only on bacterial isolation.     

Use of Rh (III)-Heteropolymolybdate as Potential Catalysts for the Removal of Nitrates in Human Drinking Water: Synthesis,Characterisation and Catalytic Performance

The investigation and development of technologies to remediate water contaminated with NO₃^? are constantly increasing. An economically and potentially effective alternative is based on the catalytic hydrogenation of NO₃^? to N₂. With this objective, bimetallic RhMo₆ catalysts based on Anderson-type heteropolyanion (RhMo₆O₂₄H₆)^3? were prepared and characteri3ed in order to obtain well-defined bimetallic catalyst. The catalysts were supported on Al₂O₃ with different textural properties and on silica. The heteropolyanion-support interaction was analysed by temperature-programmed reduction (TPR) and X-ray photoelectron spectroscopy (XPS). The differences obtained in activity and selectivity to the different products can be assigned to the different interaction between the RhMo₆ Anderson phase and the supports. The RhMo₆/G, (G: γ-Al₂O₃) system showed the best catalytic performance. This catalyst exhibited the lowest reduction temperature of Rh and Mo in the TPR assay and a Rh/Mo surface ratio similar to that of the original phase, as observed by XPS analysis. These studies allowed us to verify a synergic effect between Rh and Mo, through which Mo reducibility was promoted by the presence of the noble metal. The catalytic activity was favoured by the active sites generated from the Anderson phase. This fact was confirmed by comparing the activity of RhMo₆/G with that corresponding to a conventional catalyst prepared through successive impregnation of both Rh (III) and Mo (VI) salts.