Amy Littleton Bates

Ms. Amy Littleton Bates


Research Focus & Metrics

Academic Career Length

5Years (2022-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

View All Publications
23 January 2023 in Animals
Verified
Journal Article
Open access
PDF file
ABAmy Littleton Bates
Amy Littleton Bates
SMShawn R. McGrath
Shawn R. McGrath
MAMaxwell Bruce Allworth
Maxwell Bruce Allworth
SRSusan M. Robertson
Susan M. Robertson
GRGordon Refshauge
Gordon Refshauge
The management of ewes across southern Australia may vary with breed and can change over time and, as such, a greater understanding of producer management practices and the motivations that influence these practices is required. A cross-sectional study was performed by telephone interview with sheep producers managing Composite, Maternal, Merino or shedding ewe breeds mated in either spring, summer, or autumn. The surveyed producers were a unique subset of southern Australian producers. A large proportion of the surveyed producers followed current best practice guidelines for ewe mating and lambing nutritional management; however, some producers did not align with these targets. Further, some producers did not see the value in attaining the current recommendations. Pregnancy scanning was widely practiced, likely an artefact of the recruitment process; however, a few producers did not utilize this information for nutritional management at lambing time. Finally, most producers were active in their search for new information, seeking information regularly from a wide range of sources and reported making management changes within the last five years. Further work is required to understand why some producers are not adopting best practice where possible and to understand current barriers for adoption. Management guidelines for all sheep breeds are required to best manage sheep across southern Australia.

24 October 2022 in Animals
Verified
Journal Article
Open access
PDF file
ABAmy Littleton Bates
Amy Littleton Bates
SMShawn R. McGrath
Shawn R. McGrath
SRSusan M. Robertson
Susan M. Robertson
GRGordon Refshauge
Gordon Refshauge
Sheep production in southern Australia may vary by breed, time of year, production output (wool, meat, or both), region and seasonal influence. Sheep producers with flocks of approximately 300–500 ewes (n = 58) were recruited across southern Australia to take part in a survey and mating variables were collected from over 30,000 ewes between October 2020 and August 2021. A Bayesian Network (BN) was developed to identify the interrelatedness and most influential variable on pregnancy and fetal number (of pregnant ewes) outcomes under different scenarios. The BN analysis indicated a low association between the variables explored, however, were breed dependent. In wool-based breeds a mating liveweight of 60–69.5 kg predicted the lowest non-pregnant and greatest number of fetuses, and in shedding ewes 70–79.5 kg predicted the lowest non-pregnant rate and 90–99.5 kg the greatest number of fetuses. Pregnancy rate and fetuses per ewe were optimized at ram percentages of 1.5% for Composite and Merino ewes and 2% for Maternal ewes. A mating BCS 4 resulted in greatest pregnancy rate and number of fetuses across all breeds. Curvilinear relationships between mating liveweight, BCS and ram percentage were observed with pregnancy rate and fetal number. Practically, reproductive potential is best managed on a breed basis and with consideration of all variables explored.

24 October 2024 in Animal Production Science
Verified
Journal Article
Open access
PDF file
ABAmy Littleton Bates
Amy Littleton Bates
SRS Robertson
S Robertson
SMS Mcgrath
S Mcgrath
MAM Allworth
M Allworth
GRG Refshauge
G Refshauge
Context: Supplementary feeding may alter sheep enterprise production and profit margin, but use may vary across regions, sheep breeds and mating seasons. Supplementary feeding is a means of ensuring adequate nutrition but increases operating costs. Modelling has previously indicated the most profitable sheep enterprises optimise stocking rate and target lamb production, whereas those that minimise supplementary feeding incur the least financial risk. Aims: To explore the impact of increasing supplementary feed allowance on production, profit and financial risk. Methods: Seventy-two sheep farm enterprises were simulated across eight southern Australian locations, including three breeds and three mating seasons. For each enterprise a low grain allowance (LGA) of 30 kg/head.year (threshold used in previous modelling) was compared to a high grain allowance (HGA) of 35 kg/head.year and 42 kg/head.year for Merino and non-Merino ewes (current industry recommendations), respectively. The financial risk of each enterprise was determined via Conditional Value at Risk of gross margins over 30 years, exploring downside risk in the worst 20% of scenarios. Key results: A HGA increased production and profit in 32% of farm enterprises, but financial risk was often increased. Merino enterprises were generally the most profitable, least risky and consumed the greatest amount of supplementary feed, followed by Composite and then Maternal enterprises. Summer and autumn mating was often most profitable, but high supplement consumption in autumn-mated enterprises increased financial risk. Conclusions: Increasing supplementary feeding may improve production and profit but may also increase financial risk using the parameters examined. Implications: Producers may be able to improve the production, profit and financial risk of an enterprise through increased supplementary feeding, but this will be dependent on breed, input costs, commodity prices and location.

28 March 2026 in Smart Agricultural Technology
Verified
Journal Article
Open access
ACAnita Chang
Anita Chang
ABAmy Littleton Bates
Amy Littleton Bates
CPChristie A. Pearson
Christie A. Pearson