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Water banking in aquifers is an internationally proven, low-cost solution that could improve drought resilience across the Murray Darling Basin. While significant potential for water banking through managed aquifer recharge (MAR) or conjunctive use of surface and groundwater resources has been identified in the Murray Darling Basin Plan, there is a need to establish clear policy and institutional foundations to incentivise adoption. To provide appropriate incentives for schemes, the legal status of rights to recharge, store and recover water, and the rules and costs which apply to groundwater extraction need to be clear and transparent. This paper aims to clarify principles and frameworks to secure water rights for recharge, storage, and recovery within the sustainable limits of water resources currently set under law. The current Basin Plan supports water banking, and banking would be complementary with objective and outcomes sought by future Basin Plans. Existing water accounting systems would need to accommodate this new capacity. Institutional arrangements and financial structures of water banking in the USA provide guidance for Australia. Demonstration sites would enable concurrent policy development and institutional set-up and provide critical experience to serve as models for wider adoption as part of future Murray Darling Basin plans. [ABSTRACT FROM AUTHOR]

This case‐control study investigated associations between Campylobacter fetus or Campylobacter jejuni titre and reproductive outcomes in 22 flocks of Merino and non‐Merino maiden ewes aged 1–2 years old. Campylobacter titres were also determined for multiparous ewes aged 3 years or older on the same farms. C. fetus 'positivity' (titre ≥1:80) was detected for 12% (57/462; 95% confidence interval [95% CI] 9.6 to 15.6) of maiden ewes and 31% (65/210; 95% CI 25.0 to 37.4) of mature ewes. The odds for failing to rear a lamb in C. fetus‐'exposed' maiden ewes (titre ≥1:10) was 2.01 times that of seronegative ewes (95% CI 1.09 to 3.77; P = 0.027), but there was no association between C. fetus‐'positivity' (titre ≥1:80) and failure to rise (OR 1.69; 95% CI 0.77 to 3.76; P = 0.191). C. fetus abortions were confirmed with microbial culture in one maiden ewe flock. In this flock, C. fetus titres fluctuated and often waned by lamb marking, highlighting the value of necropsies during abortion investigations. C. jejuni‐'positivity' (titre ≥1:80) was detected for 44% (204/462; 95% CI 39.7 to 48.7) maiden ewes, but odds of failing to rear were decreased for C. jejuni‐'positive' ewes (OR 0.52; 95% CI 0.32 to 0.83; P = 0.007). The association between Campylobacter serology and the reproductive outcome was inconsistent in these flocks. Serology should be considered in the context of other risk factors and used in conjunction with other strategies to investigate the impact of Campylobacter exposure on ewe reproductive performance such as monitoring for abortions and lamb necropsies to determine aetiological diagnosis, and vaccination trials. [ABSTRACT FROM AUTHOR]

Fetal loss and lamb mortality between mid‐pregnancy and weaning are important economic and welfare issues for the Australian sheep industry. The aim of this study was to determine common causes of ovine abortion and stillbirths based on submissions to veterinary laboratories and identify factors that impact the determination of an aetiological diagnosis. Data for 529 investigations on abortion or stillbirth between 2000 and 2018 were retrieved from four state veterinary laboratories in Western Australia, South Australia, Victoria and Tasmania. An aetiological diagnosis was made for 57% of investigations. Investigations that included placental tissue samples were more than twice as likely to have an aetiological diagnosis compared to investigations without placenta (P = 0.017, 95% confidence interval 1.1, 4.5). Of the investigations where an aetiological diagnosis was made, 81% involved infectious abortion, with Campylobacter spp. (32%), Listeria spp. (25%) and Toxoplasma gondii (9%) being the three most common abortigenic pathogens implicated. The remaining 19% of investigations with an aetiological diagnosis included a wide range of infectious and non‐infectious diseases. Diagnoses made varied year to year and between states. No evidence of exotic abortigenic pathogens were reported. Veterinary practitioners can improve the probability of an aetiological diagnosis by emphasising to farmers the importance of collecting any aborted material, especially placenta, and appropriate storage of the tissues until they can be submitted to the laboratory. Some diseases that cause abortion in Australian sheep have zoonotic potential, and veterinary practitioners play an important role in educating clients about appropriate hygiene when handling pregnant and lambing ewes or any aborted material. [ABSTRACT FROM AUTHOR]

We examine the anthropogenically forced climate response for the 21st century representative concentration pathway (RCP) emission scenarios and their extensions for the period 2101-2500. The experiments were performed with ModelE2, a new version of the NASA Goddard Institute for Space Sciences (GISS) coupled general circulation model that includes three different versions for the atmospheric composition components: a noninteractive version (NINT) with prescribed composition and a tuned aerosol indirect effect (AIE), the TCAD version with fully interactive aerosols, whole-atmosphere chemistry, and the tuned AIE, and the TCADI version which further includes a parameterized first indirect aerosol effect on clouds. Each atmospheric version is coupled to two different ocean general circulation models: the Russell ocean model (GISS-E2-R) and HYCOM (GISS-E2-H). By 2100, global mean warming in the RCP scenarios ranges from 1.0 to 4.5°C relative to 1850-1860 mean temperature in the historical simulations. In the RCP2.6 scenario, the surface warming in all simulations stays below a 2°C threshold at the end of the 21st century. For RCP8.5, the range is 3.5-4.5°C at 2100. Decadally averaged sea ice area changes are highly correlated to global mean surface air temperature anomalies and show steep declines in both hemispheres, with a larger sensitivity during winter months. By the year 2500, there are complete recoveries of the globally averaged surface air temperature for all versions of the GISS climate model in the low-forcing scenario RCP2.6. TCADI simulations show enhanced warming due to greater sensitivity to CO2, aerosol effects, and greater methane feedbacks, and recovery is much slower in RCP2.6 than with the NINT and TCAD versions. All coupled models have decreases in the Atlantic overturning stream function by 2100. In RCP2.6, there is a complete recovery of the Atlantic overturning stream function by the year 2500 while with scenario RCP8.5, the E2-R climate model produces a complete shutdown of deep water formation in the North Atlantic. [ABSTRACT FROM AUTHOR]

This paper quantifies the computational complexity and parallel scalability of two algorithms for four-dimensional data assimilation (4DDA) at NASA's Global Modeling and Assimilation Office (GMAO). The first, the Goddard Earth Observing System Data Assimilation System (GEOS DAS), uses an atmospheric general circulation model (GCM) and an observation-space-based analysis system, the Physical-Space Statistical Analysis System (PSAS). GEOS DAS is very similar to global meteorological weather forecasting data assimilation systems but is used at NASA for climate research. The second, the Kalman filter, uses a more consistent algorithm to determine the forecast error covariance matrix than does GEOS DAS. For atmospheric assimilation, the gridded dynamical fields typically have more than 106 variables; therefore, the full error covariance matrix may be in excess of a teraword. For the Kalman filter this problem will require petaflop s-1 computing to achieve effective throughput for scientific research. [ABSTRACT FROM AUTHOR]

Respiratory disease is one of the main diseases of sheep in many regions globally. Respiratory syncytial virus (RSV) causes severe disease in humans and in calves, but little is known about the role of RSV in sheep. We studied the prevalence of ovine RSV in sheep processed at 5 abattoirs in southern Australia. Bronchial swab samples were collected from 182 consignments of lambs up to 12 months of age and 71 consignments of adult sheep; these were tested for the presence of the virus using a qPCR based on the F gene sequence. Six of the 253 abattoir consignments (2.4%) tested positive for ovine RSV. Four of the positive consignments were lambs and 2 were adult sheep. To our knowledge, this is the first report of the ovine strain of RSV in sheep with pneumonia from Australia. Further research is needed to clarify the role of RSV in pneumonia in sheep., (Copyright and/or publishing rights held by the Canadian Veterinary Medical Association.)

Chlamydia pecorum is a veterinary pathogen associated with abortions and perinatal mortality in sheep. Recent studies investigating foetal and perinatal lamb mortality in sheep from Australia and New Zealand identified C. pecorum clonal sequence type (ST)23 strains in aborted and stillborn lambs. Presently, there is limited genotypic information on C. pecorum strains associated with reproductive disease, although whole genome sequencing (WGS) of one abortigenic ST23 C. pecorum strain identified unique features, including a deletion in the CDS1 locus of the chlamydial plasmid. We applied WGS on two ST23 strains detected in aborted and stillborn lambs from Australia and used phylogenetic and comparative analyses to compare these to the other available C. pecorum genomes. To re-evaluate the genetic diversity of contemporary strains, we applied C. pecorum genotyping, and chlamydial plasmid sequencing to a range of C. pecorum positive samples and isolates from ewes, aborted foetuses and stillborn lambs, cattle and a goat from diverse geographical regions across Australia and New Zealand.The two new C. pecorum genomes are nearly identical to the genome of the Australian abortigenic strain including the unique deletion in the chlamydial plasmid. Genotyping revealed that these novel C. pecorum ST23 strains are widespread and associated with sheep abortions on Australian and New Zealand farms. In addition, a goat C. pecorum strain (denoted ST 304) from New Zealand was also characterised. This study expands the C. pecorum genome catalogue and describes a comprehensive molecular characterisation of the novel livestock ST23 strains associated with foetal and lamb mortality., Competing Interests: Declaration of Competing Interest The authors declare that there are no conflicts of interest. The funders had no role in the design of this study, analyses, interpretation of the data, or decision to publish., (Copyright © 2023 Elsevier B.V. All rights reserved.)

Background: Toxoplasma gondii causes reproductive losses in sheep worldwide, including Australia. The reproductive performance of primiparous ewes is typically lower than for mature, multiparous ewes, and younger ewes are more likely to be immunologically naïve and therefore more susceptible to reproductive disease if T. gondii infection occurs during pregnancy. The aim of this study was to assess the impact of infection with T. gondii on the reproductive performance of primiparous ewes in southern Australia using a prospective cohort study. This will inform the need for targeted control strategies for T. gondii in Australian sheep., Results: Toxoplasma gondii seropositivity using indirect ELISA was detected at 16/28 farms located across southern Australia. Apparent seropositivity to T. gondii was lower in primiparous ewes (1.1, 95% confidence interval (CI) 0.6, 1.8) compared to mature, multiparous ewes (8.1, 95% CI 6.0, 10.5; P < 0.001). Toxoplasma gondii seroconversion during the gestation and lambing period was confirmed for 11/1097 (1.0, 95% CI 0.5, 1.7) of pregnant primiparous ewes that failed to raise a lamb, and 1/161 (0.6, 95% CI 0.1, 2.9) primiparous ewes with confirmed mid-pregnancy abortion., Conclusions: Low frequency of detection of T. gondii seroconversion during gestation and low frequency of seropositivity to T. gondii suggests that toxoplasmosis was not an important contributor to reproductive losses in primiparous ewes on farms located over a wide geographical area in southern Australia., (© 2022. The Author(s).)

The role of infectious diseases including coxiellosis in causing poorer reproductive performance of primiparous ewes are not well studied. The aims of this study were to determine if natural exposure to Coxiella burnetii is widespread in breeding ewes and whether seropositivity is associated with poor reproductive performance of primiparous ewes. Seropositivity to Coxiella burnetii was 0.08% (CI95% 0.01, 0.36) in primiparous ewes and 0.36% (CI95% 0.07, 1.14) in mature ewes. Coxiella burnetii was not detected in aborted or stillborn lambs using qPCR. These findings suggest C. burnetii infection was unlikely to be an important contributor to abortion and perinatal mortalities observed for primiparous ewe flocks, and exposure to C. burnetii was not widespread in ewes on farms located over wide geographical region of southern Australia. Whilst ewes on these farms were not an important reservoir for C. burnetii, sporadic zoonotic transmission from sheep is reported and has public health implications., (Copyright © 2021 The Authors. Published by Elsevier Ltd.. All rights reserved.)

The contribution of abortions to the overall mortality of lambs born to maiden (primiparous) ewes in Australia remains unclear. This cohort study aimed to quantify abortion and lamb mortality for ewe lambs and maiden Merino two-tooth ewes. Lamb mortality from pregnancy scanning to marking were determined for 19 ewe lamb and 11 Merino two-tooth ewe flocks across southern Australia. Average lamb mortality from scanning to marking was 35.8% (range 14.3-71.1%) for the ewe lambs and 29.4% (range 19.7-52.7%) for the two-tooth ewes. Mid-pregnancy abortion was detected in 5.7% of ewes (range 0-50%) in the ewe lamb flocks and 0.9% of ewes (range 0-4.4%) in the two-tooth ewe flocks. Mid-pregnancy abortion affecting ≥2% of ewes was observed in 6/19 ewe lamb flocks and 2/11 two-tooth ewe flocks. Lamb mortality from birth to marking represented the greatest contributor to foetal and lamb mortality after scanning, but mid-pregnancy abortion was an important contributor to lamb mortality in some ewe lamb flocks. Variability between the flocks indicates scope to improve the overall reproductive performance for maiden ewes by reducing foetal and lamb losses. Addressing mid-pregnancy abortion may improve the reproductive performance in some flocks.

Neospora caninum has been implicated as a sporadic cause of abortion and perinatal deaths in sheep flocks globally. However, its significance as a reproductive pathogen for sheep in Australia remains unknown. The aims of this study were to (i) determine the seroprevalence of N. caninum in Australian breeding ewes and (ii) examine if natural exposure to N. caninum is associated with poor reproductive performance of primiparous ewes in southern Australia. Thirty flocks of primiparous ewes (aged 1-2 years old at lambing) from 28 farms in three states (Western Australia, South Australia and Victoria) were monitored between mating and lamb marking. Blood samples were also collected from multiparous mature ewes (aged 3 years or older) at each farm. Seroprevalence for anti-N. caninum IgG using indirect ELISA was determined for a subset of primiparous ewes that were predominantly determined to be pregnant and subsequently failed to rear a lamb (n = 1279) and randomly selected mature multiparous ewes with unknown reproductive status (n = 558). Neopsora caninum apparent seroprevalence was 0.16% (95% confidence interval 0.03%, 0.5%) in primiparous ewes, with seropositivity identified in two ewes from farms located in South Australia and Victoria. There was no evidence of seropositivity in mature ewes with apparent seroprevalence 0% (0%, 0.45%). These findings suggest that N. caninum infection was not widespread in primiparous ewes or mature multiparous ewes on these farms, and exposure to N. caninum infection was unlikely to explain abortion and perinatal mortalities observed for primiparous ewes., (© 2021. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Traditional methods of detecting Chlamydia pecorum in tissue samples such as polymerase chain reaction or cell culture are laborious and costly. We evaluated the use of a previously developed C. pecorum LAMP assay using minimally processed ovine samples. Cotyledon ( n = 16), foetal liver ( n = 22), foetal lung ( n = 2), and vaginal ( n = 6) swabs, in addition to cotyledon ( n = 6) and foetal liver ( n = 8) tissue samples, were rapidly processed and used for LAMP testing without DNA extraction. Overall, LAMP test results were highly congruent with the in-house reference qPCR, with 80.43% (37/46; 72.73% positive agreement (PA); 84.75% negative agreement (NA)) overall agreeance for swab samples, and 85.71% (12/14; 80% PA; 88.89% NA) overall agreeance for tissue samples. Out of the 11 total discrepant results, discrepancy was mainly observed in samples ( n = 10) with less than 100 copies/µL C. pecorum DNA. While sensitivity could be improved, the simplicity, low cost, and accuracy of detection makes this test amenable for use at point-of-care for detecting C. pecorum in sheep.

Lamb survival is an important welfare and productivity issue for sheep industries worldwide. Lower lamb survival has been reported for primiparous ewes, but the causes of this are not well studied. The aim of this study was to determine causes of perinatal deaths for lambs born to primiparous ewes in Western Australia, and identify if infectious diseases are implicated. Lamb mortality from birth to marking were determined for 11 primiparous ewe flocks on 10 farms in Western Australia. Lamb mortality from birth to marking averaged 14% for single-born and 26% for multiple-born lambs. Lamb necropsies (n = 298) identified starvation-mismosthering-exposure (34%), dystocia (24%) and stillbirth (15%) as the most common causes of perinatal lamb death. There was no evidence of exotic abortigenic pathogens in aborted and stillborn lambs (n = 35). Chlamydia pecorum was detected by qPCR in 15/35 aborted and stillborn lambs on 5/6 farms. Preliminary molecular characterisation of C. pecorum detected in samples from aborted and stillborn lambs (n = 8) using both Multilocus Sequence Typing and ompA genotyping indicated all strains were genetically identical to previously described pathogenic livestock strains, denoted ST23, and dissimilar to gastrointestinal strains. High frequency of detection of a pathogenic C. pecorum strains ST23 associated with ovine abortion and stillbirth on multiple farms located across a wide geographic area has not been previously reported. Chlamydia pecorum may contribute to reproductive wastage for primiparous sheep in Western Australia. Further investigation to understand C. pecorum epidemiology and impact on sheep reproduction is warranted.

Chlamydia pecorum is an obligate intracellular pathogen with a wide host range including livestock such as sheep, cattle, goats, and pigs as well as wildlife species such as koalas. Chlamydial polyarthritis is an economically important disease resulting in swollen joints, lameness, stiffness, and weight loss in young sheep. In the present study, tissues from sheep experimentally or naturally infected with Chlamydia pecorum were assessed by histopathology and immunohistochemistry. Carpal, hock, and stifle joints as well as spleen, liver, kidney, lymph nodes, lung, and brain of 35 sheep from different inoculation groups were available. Two different C. pecorum strains (IPA and E58), different routes of administration (intraarticular or intravenous), UVA-irradiated IPA strain, and corresponding noninfected control groups were investigated. Similar investigations on tissues from 5 naturally infected sheep were performed. The most obvious inflammatory lesions were observed in synovial tissues and, notably, in the renal pelvis from the experimentally infected group and naturally infected animals. This resulted in chronic or chronic-active arthritis and pyelitis. Intralesional chlamydial inclusions could be demonstrated by immunohistochemistry in both tissues. Immunohistochemical evaluation of the presence and distribution of macrophages, T and B cells in synovial tissues revealed macrophages as the most prevalent inflammatory cell population. Previous observations indicated that C. pecorum isolates can infect circulating monocytes. Together with the finding of the histological lesions in synovial tissues and internal organs alongside the presence of C. pecorum DNA, these observations suggest chlamydial arthritis in lambs is the result of hematogeneous spread of C. pecorum .

Fetal loss and lamb mortality between mid-pregnancy and weaning are important economic and welfare issues for the Australian sheep industry. The aim of this study was to determine common causes of ovine abortion and stillbirths based on submissions to veterinary laboratories and identify factors that impact the determination of an aetiological diagnosis. Data for 529 investigations on abortion or stillbirth between 2000 and 2018 were retrieved from four state veterinary laboratories in Western Australia, South Australia, Victoria and Tasmania. An aetiological diagnosis was made for 57% of investigations. Investigations that included placental tissue samples were more than twice as likely to have an aetiological diagnosis compared to investigations without placenta (P = 0.017, 95% confidence interval 1.1, 4.5). Of the investigations where an aetiological diagnosis was made, 81% involved infectious abortion, with Campylobacter spp. (32%), Listeria spp. (25%) and Toxoplasma gondii (9%) being the three most common abortigenic pathogens implicated. The remaining 19% of investigations with an aetiological diagnosis included a wide range of infectious and non-infectious diseases. Diagnoses made varied year to year and between states. No evidence of exotic abortigenic pathogens were reported. Veterinary practitioners can improve the probability of an aetiological diagnosis by emphasising to farmers the importance of collecting any aborted material, especially placenta, and appropriate storage of the tissues until they can be submitted to the laboratory. Some diseases that cause abortion in Australian sheep have zoonotic potential, and veterinary practitioners play an important role in educating clients about appropriate hygiene when handling pregnant and lambing ewes or any aborted material., (© 2020 Australian Veterinary Association.)

Present-day Venus is an inhospitable place with surface temperatures approaching 750K and an atmosphere 90 times as thick as Earth's. Billions of years ago the picture may have been very different. We have created a suite of 3-D climate simulations using topographic data from the Magellan mission, solar spectral irradiance estimates for 2.9 and 0.715 Gya, present-day Venus orbital parameters, an ocean volume consistent with current theory, and an atmospheric composition estimated for early Venus. Using these parameters we find that such a world could have had moderate temperatures if Venus had a rotation period slower than ~16 Earth days, despite an incident solar flux 46-70% higher than Earth receives. At its current rotation period, Venus's climate could have remained habitable until at least 715 million years ago. These results demonstrate the role rotation and topography play in understanding the climatic history of Venus-like exoplanets discovered in the present epoch.