Article
Veterinary Sciences
Thomas Clune, Amy Lockwood, Serina Hancock, Andrew N. Thompson, Mieghan Bruce, Sue Beetson, Angus J. Campbell, Elsa Glanville, Daniel Brookes, Colin Trengove, Ryan O'Handley, Caroline Jacobson
Summary: This study aimed to assess the impact of Toxoplasma gondii infection on the reproductive performance of primiparous ewes in southern Australia. The results showed a low frequency of detection of T. gondii seroconversion during gestation and a low frequency of seropositivity to T. gondii, suggesting that toxoplasmosis was not a major contributor to reproductive losses in primiparous ewes on farms located over a wide geographical area in southern Australia.
BMC VETERINARY RESEARCH
(2022)
Article
Agriculture, Dairy & Animal Science
Dayna Hutchison, Bronwyn E. Clarke, Serina Hancock, Andrew N. Thompson, Elise Bowen, Caroline Jacobson
Summary: The reproductive performance of maiden ewes is poorer than that of multiparous ewes, and the extent and causes of this difference are not well understood in Australian sheep farming. This study compared the reproductive performance of maiden ewes and multiparous ewes on the same farms and found significant differences in lamb marking rate and reproductive success. Strategies to improve reproductive rate and lamb survival can address the suboptimal reproductive performance of maiden ewes.
Article
Veterinary Sciences
Tom Clune, Shane Besier, Sam Hair, Serina Hancock, Amy Lockwood, Andrew Thompson, Martina Jelocnik, Caroline Jacobson
Summary: This study investigated the causes of perinatal lamb deaths for lambs born to primiparous ewes in Western Australia. The main causes of death were identified as starvation-mismosthering-exposure, dystocia, and stillbirth. Additionally, a pathogenic strain of Chlamydia pecorum (ST23) was detected in aborted and stillborn lambs on multiple farms.
VETERINARY RESEARCH
(2021)
Review
Agriculture, Dairy & Animal Science
Paul R. Kenyon, Rene A. Corner-Thomas
Summary: This review provides an overview of the advantages and disadvantages of breeding ewe lambs, as well as factors affecting breeding success and management guidelines. It highlights the differences between ewe lamb and mature ewe reproductive performance, and outlines the potential long-term consequences of breeding ewe lambs. The review also identifies areas requiring further research.
Article
Parasitology
Thomas Clune, Amy Lockwood, Serina Hancock, Mieghan Bruce, Andrew N. Thompson, Sue Beetson, Angus J. Campbell, Elsa Glanville, Daniel Brookes, Colin Trengove, Ryan O'Handley, Caroline Jacobson
Summary: The study revealed a low seroprevalence of N. caninum in Australian breeding ewes, and exposure to the pathogen was unlikely to explain the abortion and perinatal mortalities observed in primiparous ewes.
PARASITOLOGY RESEARCH
(2021)
Article
Reproductive Biology
Amellia Redfearn, Estelle Janodet, Jody McNally, Heather Brewer, Emma Doyle, Rebecca Doyle, Sabine Schmoelzl
Summary: Dystocia is a major cause of lamb mortality, leading to newborn hypoxia, CNS damage, increased risk of starvation, exposure, mismothering and death. This study found that dystocic ewes exhibited lower expression of maternal behaviors and higher expression of avoidance behaviors, as well as performing fewer behaviors overall compared to eutocic ewes. Dystocia significantly affects the quality and quantity of ewe maternal behavior, increasing the risk of lamb avoidance, maternal disinterest, and lamb death.
Article
Agriculture, Dairy & Animal Science
Anne L. Ridler, Kate J. Flay, Paul R. Kenyon, Hugh T. Blair, Rene A. Corner-Thomas, Emma J. Pettigrew
Summary: This study investigated the factors associated with lamb mortality and its cause, comparing lambs born to ewe hoggets with those born to mature-age ewes. The study found that low birthweight, multiple litter size, and increasing ewe hogget average daily gain during pregnancy were risk factors for lamb mortality. Stillbirth was the most common cause of mortality for lambs born to ewe hoggets, and the risk factors for stillbirth were similar to those for overall lamb mortality. Different causes of mortality were observed between lambs born to ewe hoggets and those born to mature-age ewes.
Article
Agriculture, Multidisciplinary
B. B. Odevci, E. Emsen, M. N. Aydin
Summary: Lamb survival is influenced by a series of events including genetics, physiology, behavior, and nutrition, with the environment playing a key role. Machine learning algorithms were used to identify factors affecting lamb survival in high altitudes and cold climates. Classification Trees outperformed other algorithms in predicting lamb survival, lamb behavior, and mothering ability in this study.
COMPUTERS AND ELECTRONICS IN AGRICULTURE
(2021)
Article
Immunology
Tom Clune, Amy Lockwood, Serina Hancock, Andrew N. Thompson, Sue Beetson, Mieghan Bruce, Angus J. Campbell, Elsa Glanville, Daniel Brookes, Colin Trengove, Ryan O'Handley, Caroline Jacobson
Summary: Infection rate of Coxiella burnetii is low in primiparous ewes and does not affect reproductive performance, while exposure in sheep across southern Australia is not widespread. Although ewes are not significant reservoirs, sporadic zoonotic transmission poses public health implications.
COMPARATIVE IMMUNOLOGY MICROBIOLOGY AND INFECTIOUS DISEASES
(2022)
Article
Multidisciplinary Sciences
Michelle A. E. Anderson, Estela Gonzalez, Joshua X. D. Ang, Lewis Shackleford, Katherine Nevard, Sebald A. N. Verkuijl, Matthew P. P. Edgington, Tim Harvey-Samuel, Luke Alphey
Summary: CRISPR/Cas9-based homing gene drives are a potential new approach to mosquito control. In this study, researchers successfully generated transgenic Ae. aegypti lines expressing Cas9, which significantly biased the inheritance of an sgRNA-expressing element. The sds3G1-Cas9 isolate showed the highest average inheritance, indicating its potential for driving the spread of the targeted element more efficiently.
NATURE COMMUNICATIONS
(2023)
Article
Biology
Cornelius L. Nel, Schalk W. P. Cloete, Annelie C. M. Kruger, Kennedy Dzama
Summary: Adverse weather conditions can affect mortality in new-born lambs. The Elsenburg Merino flock showed divergent responses in reproduction and lamb survival due to genetic selection based on number of lambs weaned. The positively selected H-Line lambs exhibited higher neonatal rectal temperature and lower mortality rates in response to cold stress compared to the negatively selected L-Line.
JOURNAL OF THERMAL BIOLOGY
(2021)
Review
Veterinary Sciences
Mieghan Bruce, John M. Young, David G. Masters, Gordon Refshauge, Andrew N. Thompson, Paul R. Kenyon, Ralph Behrendt, Amy Lockwood, David W. Miller, Caroline Jacobson
Summary: Dystocia contributes to significant lamb and ewe mortality in sheep production in Australia and New Zealand. The financial impacts of dystocia on the Australian sheep industry are substantial, and reducing dystocia through improved genetics and management can lead to improved animal welfare and farm profit.
PREVENTIVE VETERINARY MEDICINE
(2021)
Article
Agriculture, Dairy & Animal Science
C. E. Pritchard, A. P. Williams, P. Davies, D. Jones, A. R. Smith
Summary: Providing additional artificial shelters for pregnant ewes in outdoor lambing systems in upland farms in the UK can significantly reduce shepherding problems caused by adverse weather conditions. Highlander ewes are more likely to seek shelter and require fewer interventions when facing issues compared to Aberfield ewes. This highlights the substantial benefits to animal welfare and productivity that can be achieved through shelter provision in UK upland outdoor lambing systems.
Article
Agriculture, Dairy & Animal Science
Emma Pettigrew, Rebecca Hickson, Steve Morris, Paul Kenyon, Rene Corner-Thomas, Emmanuelle Haslin, Hugh Blair
Summary: The experiment compared the differences in weight, body condition score, and reproduction rate between lambs born to ewe lambs and mature ewes. The results showed that lambs born to ewe lambs were lighter until two years of age, but if heavy enough, had similar reproduction rates and body condition scores compared to lambs born to mature ewes.
Article
Agriculture, Multidisciplinary
Emmanuelle Haslin, Rene A. Corner-Thomas, Paul R. Kenyon, Steve T. Morris, Hugh T. Blair
Summary: Ewe lamb live weight at first mating is positively associated with reproductive performance. Heavier mating live weight leads to better fertility and lambing percentage. However, the live weights of their progeny are not affected. It is recommended to mate ewe lambs at a live weight of 50-55 kg for maximum reproductive performance.
NEW ZEALAND JOURNAL OF AGRICULTURAL RESEARCH
(2022)
Article
Food Science & Technology
Zahra B. Naqvi, Michael A. Campbell, S. Latif, Peter C. Thomson, David M. McGill, Robyn D. Warner, Michael A. Friend
Summary: The study found significant interactions between concentrate feeding, ginger powder injection, cooking temperature, and time, with increasing zingibain concentration leading to reduced WBSF, increased collagen solubility, and MFI. Injecting zingibain along with sous vide cooking demonstrated the weakening effect on myofibrillar and connective tissue proteins, resulting in enhanced collagen solubility and tenderness in BF.
Article
Agriculture, Dairy & Animal Science
Amy L. Bates, Shawn R. McGrath, Susan M. Robertson, Gordon Refshauge
Summary: This study investigated the influence of mating conditions and management practices on sheep reproduction and nutrition in southern Australia. The results highlight the interrelationships between these variables and emphasize the importance of optimizing sheep reproduction.
Article
Agriculture, Dairy & Animal Science
Amy L. Bates, Shawn R. McGrath, Maxwell B. Allworth, Susan M. Robertson, Gordon Refshauge
Summary: Best practice guidelines for managing Maternal and Merino ewes in southern Australia are available, but lacking for Composite and shedding breeds. A survey was conducted to explore the management practices and motivations of a unique group of sheep producers in southern Australia. Most respondents followed best practice guidelines for mating and lambing, but a smaller group did not value nutritional and mating length recommendations. Producers actively sought new information and made management changes, indicating a need for understanding barriers to best practice adoption and development of guidelines for all sheep breeds.
Article
Agronomy
John C. C. Broster, Allison J. J. Chambers, Leslie A. A. Weston, Michael J. J. Walsh
Summary: The study examined the relationships between weed and crop species in Australian farming systems through surveys of randomly selected fields. It found that annual ryegrass, wild oats, and sowthistle were the most common weed species in NSW cropping fields, with varying distribution patterns between regions. Changes in weed species occurrence were attributed to alterations in crop production practices.
Article
Veterinary Sciences
S. M. Robertson, M. A. Friend
Summary: Retention of aging ewes is a strategy to maintain or increase flock size, but it comes with risks of mortality and health issues. This study examined the incidence and causes of mortality and culling in a flock of Merino ewes as they aged from 4.5 to 10.5 years. The annual mortality rate ranged from 6.2% to 9.9%, with lambing complications being the major cause. The annual culling rates ranged from 1.6% to 42.8%, primarily for replacement with younger ewes rather than essential culling for welfare and productivity.
AUSTRALIAN VETERINARY JOURNAL
(2023)
Article
Veterinary Sciences
F. Ataollahi, S. McGrath, M. Friend, G. Dutton, A. Peters, M. Bhanugopan
Summary: Our study investigated the effects of supplementing calcium, magnesium, and sodium to lactating ewes and lambs grazing barley forage. Supplemented groups had access to mineral supplements while control groups did not. Samples were collected from ewes and lambs at different time points, and it was found that the concentration of forage minerals decreased over time. Liveweight gain was greater in the first 14 days compared to the later period. The study concludes that mineral supplementation during late lactation is beneficial for weight gain in lambs.
AUSTRALIAN VETERINARY JOURNAL
(2023)
Article
Agronomy
John C. Broster, Adam Jalaludin, Michael J. Widderick, Allison J. Chambers, Michael J. Walsh
Summary: Glyphosate has been widely used to control summer annual weeds in fallow systems in Australia's northern grains region, but the increasing cases of glyphosate resistance in weed species have raised concerns about its future viability. A seed collection survey conducted between 2016 and 2018 revealed that glyphosate resistance was widespread in fleabane and prevalent in feathertop Rhodes grass, windmill grass, and awnless barnyard grass. Only a small percentage of sowthistle populations showed resistance to glyphosate. Other herbicides, such as 2,4-D amine, propaquizafop, and clethodim, provided effective control of the tested broadleaf and grass weeds. The survey results highlight the need for farmers and agronomists to incorporate non-chemical weed management tactics to ensure the sustainability of herbicides.
Article
Agronomy
Angus Malmo, John C. Broster, Michael J. Walsh
Summary: Summer annual weed species in northern Australian summer fallows are frequently present at low densities and are increasingly glyphosate-resistant. This study aimed to identify herbicides that could be used as alternatives to control Chloris virgata and Sonchus oleraceus plants. While some herbicide treatments showed control of S. oleraceus, consistent control or replacement for C. virgata was not achieved. Glyphosate was the only effective herbicide for C. virgata, highlighting the need for alternative approaches to preserve the effectiveness of glyphosate.
Review
Veterinary Sciences
Rory P. P. Nevard, Sameer D. D. Pant, John C. C. Broster, Scott T. T. Norman, Cyril P. P. Stephen
Summary: The general consensus on maternal behavior in free-ranging beef cattle was reviewed, and factors that may affect these behaviors were explored. The influence of hormones on maternal behavior in various species, including cattle, was described. Current methods of measuring behavior were also summarized.
VETERINARY SCIENCES
(2023)
Article
Agriculture, Dairy & Animal Science
Susan M. Robertson, Alexandra Morona, Allan Gunn, John Piltz, Christopher J. Scott, Michael A. Friend
Summary: The study shows that feeding sheep complete rations at maintenance energy levels every two days during joining does not affect reproductive performance and wool quality compared to daily feeding.
ANIMAL PRODUCTION SCIENCE
(2023)
Article
Agriculture, Dairy & Animal Science
Susan M. Robertson, Shawn R. McGrath, Samuel Scarlett, Marie Bhanugopan, Janelle E. Hocking Edwards, Emma Winslow, Serina Hancock, Andrew N. Thompson, Gordon Refshauge, Michael A. Friend
Summary: Supplementation of calcium and magnesium did not increase lamb survival.
ANIMAL PRODUCTION SCIENCE
(2022)
Article
Agriculture, Multidisciplinary
John Broster, Peter Boutsalis, Gurjeet S. Gill, Christopher Preston
Summary: This study investigated the resistance to herbicides in annual ryegrass populations in south-eastern Australian grain production systems. The results revealed widespread resistance to multiple herbicides, with significant differences in resistance levels observed between different regions. This finding highlights the importance of implementing effective weed control strategies to minimize yield losses and control costs associated with resistant annual ryegrass populations.
CROP & PASTURE SCIENCE
(2022)
