Using Pen-Side Measurable Blood Parameters to Predict or Identify Dystocic Lambing Events

Dystocia is the greatest contributor to neonatal lamb mortality in Australia and poses significant welfare and economic concerns worldwide. In this study, we set out to investigate whether pen-side analysis technology could be employed to detect blood parameters predictive of dystocic labour events in sheep. In a pilot trial, we collected and analysed blood samples in pen-side assays for glucose, lactate, pH, pCO2, pO2, base excess, HCO3, TCO2, sO2, lactate, sodium, potassium, chloride, calcium, urea nitrogen, creatinine, haematocrit, haemoglobin and anion gap. From the pilot data, we identified creatinine, TCO2, chloride and calcium as potentially useful markers. To develop a time course and to establish variability of the selected blood parameters, a time series of samples was collected from 12 ewes, from mid-gestation to 48 h after birth. For the main trial, blood samples were collected at mid- and late gestation for glucose determination and for the full set of blood parameters at three time points before, at and after birth. Possible predictors of lambing difficulty were chloride, haematocrit and haemoglobin, sampled one week before birth; creatinine, sampled at birth; and blood pH and base excess after birth. In conclusion, we found that pen-side analysis of blood markers showed promise in identifying dystocic lambing events

The need for fresh blood: understanding organizational age inequality through a vampiric lens

YesThis article argues that older age inequality within and across working life is the result of vampiric forms and structures constitutive of contemporary organizing. Rather than assuming ageism occurs against a backdrop of neutral organizational processes and practices, the article denaturalizes (and in the process super-naturalizes) organizational orientations of ageing through three vampiric aspects: (un)dying, regeneration and neophilia. These dimensions are used to illustrate how workplace narratives and logics normalize and perpetuate the systematic denigration of the ageing organizational subject. Through our analysis it is argued that older workers are positioned as inevitable ‘sacrificial objects’ of the all-consuming immortal organization. To challenge this, the article explicitly draws on the vampire and the vampiric in literature and popular culture to consider the possibility of subverting existing notions of the ‘older worker’ in order to confront and challenge the subtle and persistent monstrous discourses that shape organizational life

Evaluating the potential of SSR flanking regions for examining taxonomic relationships in Vitaceae

Three EST-derived microsatellite loci from Vitis vinifera were amplified and sequenced across eight species of Vitaceae from four different genera. Phylogenetic analysis of the microsatellite’s flanking regions produced informative results in congruence with previous studies. Generic relationships were respected and the data produced sufficient inter-specific variation to distinguish between Cayratia acris and Cayratia saponaria, two very closely related species. Overall, the sequence alignments showed that priming sites were conserved, whereas microsatellite repeats were present in most cases but structurally variable. The sequence data provided information on the evolutionary patterns of various microsatellite repeats and their correlation to evolutionary relationships among taxa

Using Pen-Side Measurable Blood Parameters to Predict or Identify Dystocic Lambing Events

Dystocia is the greatest contributor to neonatal lamb mortality in Australia and poses significant welfare and economic concerns worldwide. In this study, we set out to investigate whether pen-side analysis technology could be employed to detect blood parameters predictive of dystocic labour events in sheep. In a pilot trial, we collected and analysed blood samples in pen-side assays for glucose, lactate, pH, pCO2, pO2, base excess, HCO3, TCO2, sO2, lactate, sodium, potassium, chloride, calcium, urea nitrogen, creatinine, haematocrit, haemoglobin and anion gap. From the pilot data, we identified creatinine, TCO2, chloride and calcium as potentially useful markers. To develop a time course and to establish variability of the selected blood parameters, a time series of samples was collected from 12 ewes, from mid-gestation to 48 h after birth. For the main trial, blood samples were collected at mid- and late gestation for glucose determination and for the full set of blood parameters at three time points before, at and after birth. Possible predictors of lambing difficulty were chloride, haematocrit and haemoglobin, sampled one week before birth; creatinine, sampled at birth; and blood pH and base excess after birth. In conclusion, we found that pen-side analysis of blood markers showed promise in identifying dystocic lambing events

Conservation genetics of an endangered rainforest tree (Fontainea oraria – Euphorbiaceae) and implications for closely related species

Four new eastern Australian Fontainea species have beenrecently described and all have a limited distribution. F.oraria is the rarest, being restricted to 10 adult individualswithin a single site in regrowth littoral rainforest. In order todevelop adequate management strategies, this study was aimed atsurveying the genetic variability remaining within the species by usingRAPD analysis. To assist with the correct interpretation of the results,a matching study was conducted on four populations of the closelyrelated F. australis. Similar amounts of within-populationgenetic diversity were recorded for both species. The RAPD-based studysuggested that adult plants are contributing unevenly to successivegenerations. RAPD analysis also recognised a close evolutionaryrelationship between F. oraria and F. australis.Sequencing of cpDNA (trnL-F) and nrDNA (ITS2) regions,confirmed recent divergence and possibly some historical reticulationbetween these two species and two other members of the genus. Ofparticular interest was the recognition that one of the F.australis populations (Limpinwood) represented a novel genotypiccombination in need of conservation attention. The implications of theRAPD and sequencing results are discussed in reference to theirinfluence upon the development of adequate conservation strategies forall important conservation units

Trichostrongylus colubriformis larvae induce necrosis and release of IL33 from intestinal epithelial cells in vitro: Implications for gastrointestinal nematode vaccine design

Gastrointestinal nematodes represent a major production problem for ruminant livestock. Enhancing immunity to gastrointestinal nematodes through vaccination is desirable but mechanistic understanding of initial host responses that facilitate gastrointestinal nematode protective immunity is limited. We hypothesise that gastrointestinal nematode invasion induces mucosal epithelium damage and alarmin (e.g. IL33) release, thereby contributing to initiation of protective gastrointestinal nematode immunity. To test this, an in vitro air-liquid interface human HT-29 epithelial cell-Trichostrongylus colubriformis co-culture system was developed. Exsheathed L3 T. colubriformis exhibited both sinusoidal and burrowing motions in the co-culture system. Burrowing parasites, but not ivermectin-paralysed larvae, induced necrotic death of epithelial cells (annexin V /propidium iodide /caspase 3/7 ). Microscopy confirmed that larvae consumed labelled necrotic epithelial cell contents. Trichostrongylus colubriformis larvae and their post-exsheathment antigens (excretory/secretory products) significantly induced IL33 mRNA expression in the epithelial cells. Immunoblot confirmed that IL33 was released from epithelial cells due to the damage caused by motile larvae. Exposure of HT-29 cells to alum or Sigma proprietary adjuvants induced significant epithelial cell IL33 mRNA expression without inducing cellular necrosis. Hence, the intracellular contents were not released externally where they might exert alarmin activity and this may limit their ability to trigger a protective anti-gastrointestinal nematode response. We conclude that T. colubriformis motion at the infection site induces intestinal epithelial cell necrosis which facilitates the release of intracellular contents, including IL33, and may be fundamental to the initiation of an appropriate host response to gastrointestinal nematodes. Our co-culture model is useful for studying initial epithelial cell-parasite interactions without conducting expensive animal trials

Real-time PCR quantification of infectious laryngotracheitis virus in chicken tissues, faeces, isolator-dust and bedding material over 28 days following infection reveals high levels in faeces and dust

Infectious laryngotracheitis (ILT) is an important disease of chickens caused by ILT virus (ILTV). We used the Australian SA2 and A20 vaccine strains of ILTV to determine tissue distribution and excretion characteristics of ILTV in specific-pathogen-free chickens and to determine whether ILTV is readily detectable in environmental samples such as faeces, bedding material and dust using real-time quantitative PCR. Three groups of 10 freshly hatched chicks were placed in isolators and infected orally with high doses of the two strains of vaccine virus or left unchallenged as controls. Over a 28-day post-infection (p.i.) period, faecal and serum samples were collected at frequent intervals from six individually identified chickens in each group. Dust and litter samples from the isolators were collected less frequently. Tissue samples were collected from three to four sacrificed or dead/euthanized birds at 6, 14 and 28 days p.i. Infection resulted in clinical ILT, a pronounced antibody response and sustained qPCR detection of the viral genome in the trachea, Harderian gland, lung and kidney up to 28 days p.i. A high level of the viral genome was also detected in faeces between 2 and 7 days p.i., declining by about approximately four orders of magnitude to low, but detectable, levels at 21 and 28 days p.i. The finding of high-level shedding of ILTV in faeces warrants further investigation into the epidemiological role of this, and the sustained high levels of ILTV observed in dust suggest that it may be a useful sample material for monitoring ILTV status in flocks

Analysis of antibody levels in egg yolk for detection of exposure to Ascaridia galli parasites in commercial laying hens

Ascaridia galli is one of the most abundant nematode parasites in poultry. A. galli infections can significantly impact the profitability of egg farms and have negative implications for bird health and welfare. The main objectives of this study were to determine whether A. galli specific antibodies in egg yolks can be used to detect prior or current exposure to A. galli in laying hens, and to distinguish between eggs obtained from caged and free-range hens. Twenty-two laying hen flocks from different production systems (10 free-range, 2 barn-housed and 9 caged flocks) were enrolled in the study. An in-house enzyme-linked immunosorbent assay (ELISA) was used to analyze levels of A. galli specific antibodies in yolk. The numbers of A. galli eggs in hen excreta were also determined in a subset of farms. Free-range flocks had higher and also more variable levels of anti-A. galli antibodies in the egg yolk compared to those of the cage flocks (0.50 ± 0.39 versus 0.16 ± 0.13 OD units) (

Inclusion of features derived from a mixture of time window sizes improved classification accuracy of machine learning algorithms for sheep grazing behaviours

Inertial motion sensors located on the animal have been used to study the behaviour of ruminant livestock. The time window size of segmented signal data can significantly affect the classification accuracy of animal behaviours. To date, there have been no studies evaluating the impact of a mixture of time window size features on the accuracy of animal behaviour classification. In this study, data was collected from accelerometers attached to the neck of 17 Merino sheep over a period of two days. We also recorded a ground truth dataset of behaviour recordings (grazing, ruminating, walking, and standing) over the same time period, We then investigated the ability of three machine learning (ML) approaches, Random Forest (RF), Support Vector Machine (SVM) and linear discriminant analysis (LDA), to accurately classify sheep behaviour. Our results clearly show that simultaneous inclusion of features derived from time windows of mixed sizes, ranging from 2 to 15 s, significantly improved the behaviour classification accuracy, in comparison to those determined from a single unique time window size. Of the three ML methods applied here, the RF approach yielded the best results. Together our results show that including features obtained from mixed window sizes improved the classification accuracy of sheep behaviours