73 research outputs found

    Effect of a single dose of Saccharomyces cerevisiae var. boulardii on the occurrence of porcine neonatal diarrhoea

    Get PDF
    Piglet neonatal diarrhoea is an important issue in modern pig production and is linked to increased mortality and poor growth rates, affecting long-term pig health, increasing use of medication and cost of production. Saccharomyces cerevisiae var. boulardii (SB) is a probiotic yeast with documented clinical efficacy in the prevention and treatment of diarrhoeal diseases in humans. The objectives of the current study were to evaluate the effect of SB on occurrence and severity of neonatal diarrhoea in piglets, mortality and growth rate. Forty-six litters (606 piglets) were randomly allocated to a control or SB treatment (n=23 per treatment). Within 24 h of farrowing, piglets assigned to the SB treatment received a single oral dose of a paste containing 3.3Γ—109 CFU of SB CNCM I-1079. Piglets from the control litters received a placebo paste. Piglet weight, mortality and diarrhoea were recorded up to day 7 of age. It was shown that numbers of diarrhoea days were significantly correlated with increased mortality rate and reduced weight gain (P<0.05). SB treatment had no effect on growth or mortality in diarrhoeic litters. However, SB-supplemented litters had significantly lower faecal scores, indicating firmer faeces (P<0.01) and fewer numbers of diarrhoeic days (P<0.01) during the 1st week of life. Reduction in the number of diarrhoeic litters compared with the control group was observed following the probiotic administration (P<0.05). These results highlight the detrimental effects of neonatal diarrhoea on pre-weaning performance and suggest that SB, by reducing diarrhoea duration and severity, has the potential of improving enteric health in the early stages of life in pigs

    The Earliest Post-Paleozoic Freshwater Bivalves Preserved in Coprolites from the Karoo Basin, South Africa

    Get PDF
    Background: Several clades of bivalve molluscs have invaded freshwaters at various times throughout Phanerozoic history. The most successful freshwater clade in the modern world is the Unionoida. Unionoids arose in the Triassic Period, sometime after the major extinction event at the End-Permian boundary and are now widely distributed across all continents except Antarctica. Until now, no freshwater bivalves of any kind were known to exist in the Early Triassic. Principal Findings: Here we report on a faunule of two small freshwater bivalve species preserved in vertebrate coprolites from the Olenekian (Lower Triassic) of the Burgersdorp Formation of the Karoo Basin, South Africa. Positive identification of these bivalves is not possible due to the limited material. Nevertheless they do show similarities with Unionoida although they fall below the size range of extant unionoids. Phylogenetic analysis is not possible with such limited material and consequently the assignment remains somewhat speculative. Conclusions: Bivalve molluscs re-invaded freshwaters soon after the End-Permian extinction event, during the earliest part of the recovery phase during the Olenekian Stage of the Early Triassic. If the specimens do represent unionoids then these Early Triassic examples may be an example of the Lilliput effect. Since the oldest incontrovertible freshwater unionoids are also from sub-Saharan Africa, it is possible that this subcontinent hosted the initial freshwater radiation of the Unionoida. This find also demonstrates the importance of coprolites as microenvironments of exceptional preservation that contai

    Spondarthritis in the Triassic

    Get PDF
    Background: The evidence of several forms of arthritis has been well documented in the fossil record. However, for pre-Cenozoic vertebrates, especially regarding reptiles, this record is rather scarce. In this work we present a case report of spondarthritis found in a vertebral series that belonged to a carnivorous archosaurian reptile from the Lower Triassic (,245 million years old) of the South African Karoo. Methodology/Principal Findings: Neutron tomography confirmed macroscopic data, revealing the ossification of the entire intervertebral disc space (both annulus fibrosus and nucleus pulposus), which supports the diagnosis of spondarthritis. Conclusions/Significance: The presence of spondarthritis in the new specimen represents by far the earliest evidence of any form of arthritis in the fossil record. The present find is nearly 100 million years older than the previous oldest report of this pathology, based on a Late Jurassic dinosaur. Spondarthritis may have indirectly contributed to the death of the anima

    Global Taxonomic Diversity of Anomodonts (Tetrapoda, Therapsida) and the Terrestrial Rock Record Across the Permian-Triassic Boundary

    Get PDF
    The end-Permian biotic crisis (∼252.5 Ma) represents the most severe extinction event in Earth's history. This paper investigates diversity patterns in Anomodontia, an extinct group of therapsid synapsids (β€˜mammal-like reptiles’), through time and in particular across this event. As herbivores and the dominant terrestrial tetrapods of their time, anomodonts play a central role in assessing the impact of the end-Permian extinction on terrestrial ecosystems. Taxonomic diversity analysis reveals that anomodonts experienced three distinct phases of diversification interrupted by the same number of extinctions, i.e. an end-Guadalupian, an end-Permian, and a mid-Triassic extinction. A positive correlation between the number of taxa and the number of formations per time interval shows that anomodont diversity is biased by the Permian-Triassic terrestrial rock record. Normalized diversity curves indicate that anomodont richness continuously declines from the Middle Permian to the Late Triassic, but also reveals all three extinction events. Taxonomic rates (origination and extinction) indicate that the end-Guadalupian and end-Permian extinctions were driven by increased rates of extinction as well as low origination rates. However, this pattern is not evident at the final decline of anomodont diversity during the Middle Triassic. Therefore, it remains unclear whether the Middle Triassic extinction represents a gradual or abrupt event that is unique to anomodonts or more common among terrestrial tetrapods. The end-Permian extinction represents the most distinct event in terms of decline in anomodont richness and turnover rates

    Evolution of Salmonella enterica Virulence via Point Mutations in the Fimbrial Adhesin

    Get PDF
    Whereas the majority of pathogenic Salmonella serovars are capable of infecting many different animal species, typically producing a self-limited gastroenteritis, serovars with narrow host-specificity exhibit increased virulence and their infections frequently result in fatal systemic diseases. In our study, a genetic and functional analysis of the mannose-specific type 1 fimbrial adhesin FimH from a variety of serovars of Salmonella enterica revealed that specific mutant variants of FimH are common in host-adapted (systemically invasive) serovars. We have found that while the low-binding shear-dependent phenotype of the adhesin is preserved in broad host-range (usually systemically non-invasive) Salmonella, the majority of host-adapted serovars express FimH variants with one of two alternative phenotypes: a significantly increased binding to mannose (as in S. Typhi, S. Paratyphi C, S. Dublin and some isolates of S. Choleraesuis), or complete loss of the mannose-binding activity (as in S. Paratyphi B, S. Choleraesuis and S. Gallinarum). The functional diversification of FimH in host-adapted Salmonella results from recently acquired structural mutations. Many of the mutations are of a convergent nature indicative of strong positive selection. The high-binding phenotype of FimH that leads to increased bacterial adhesiveness to and invasiveness of epithelial cells and macrophages usually precedes acquisition of the non-binding phenotype. Collectively these observations suggest that activation or inactivation of mannose-specific adhesive properties in different systemically invasive serovars of Salmonella reflects their dynamic trajectories of adaptation to a life style in specific hosts. In conclusion, our study demonstrates that point mutations are the target of positive selection and, in addition to horizontal gene transfer and genome degradation events, can contribute to the differential pathoadaptive evolution of Salmonella

    The Canadian Healthy Infant Longitudinal Development (CHILD) birth cohort study: Assessment of environmental exposures

    Get PDF
    The Canadian Healthy Infant Longitudinal Development birth cohort was designed to elucidate interactions between environment and genetics underlying development of asthma and allergy. Over 3600 pregnant mothers were recruited from the general population in four provinces with diverse environments. The child is followed to age 5 years, with prospective characterization of diverse exposures during this critical period. Key exposure domains include indoor and outdoor air pollutants, inhalation, ingestion and dermal uptake of chemicals, mold, dampness, biological allergens, pets and pests, housing structure, and living behavior, together with infections, nutrition, psychosocial environment, and medications. Assessments of early life exposures are focused on those linked to inflammatory responses driven by the acquired and innate immune systems. Mothers complete extensive environmental questionnaires including time-activity behavior at recruitment and when the child is 3, 6, 12, 24, 30, 36, 48, and 60 months old. House dust collected during a thorough home assessment at 3–4 months, and biological specimens obtained for multiple exposure-related measurements, are archived for analyses. Geo-locations of homes and daycares and land-use regression for estimating traffic-related air pollution complement time-activity-behavior data to provide comprehensive individual exposure profiles. Several analytical frameworks are proposed to address the many interacting exposure variables and potential issues of co-linearity in this complex data set

    Drug-drug interactions and QT prolongation as a commonly assessed cardiac effect - comprehensive overview of clinical trials

    Full text link

    Cranial description and taxonomic re-evaluation of Kannemeyeria argintinensis (Therapsida: Dicynodontia)

    No full text
    Examination of the holotype skull of the Triassic dicynodont Kannemeyeria argentinensis Bonaparte reveals that many of purported diagnostic characters are distortion-related. A redescription of the holotype indicates that its inclusion in the genus Kannemeyeria cannot be supported. Several characters are, however, identical to the Argentine taxon Vinceria, and we suggest that the two taxa may be congeneric. This finding challenges the validity of a global Kannemeyeria-biochron, but not necessarily the relationships of tetrapod faunal groups in South America and Africa.The Council's Research Committee, University of the Witwatersrand; National Research Foundation (NRF); Palaeontological Scientific Trust (PAST)JNC2016https://www.wits.ac.za/esi/palaeontologia-africana
    • …
    corecore