Sara Ziegler

Ms. Sara Ziegler

orcid

Research Focus & Metrics

Academic Career Length

6Years (2021-Present)

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

Representative Publications

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4 August 2021 in Renewable Agriculture and Food Systems
Verified
Journal Article
Open access
PDF file
MSMiriam Allison Snider
Miriam Allison Snider
SZSara Ziegler
Sara Ziegler
HDHeather M. Darby
Heather M. Darby
KSKathy J Soder
Kathy J Soder
ABAndré Brito
André Brito
MNMeredith Niles
Meredith Niles
Organic, grassfed (OGF) dairy, which requires higher pasture and forage dry matter intake compared with standard organic dairy practices, is unique both in its management needs and in production challenges. The OGF dairy sector is rapidly growing, with the expansion of this industry outpacing other dairy sectors. There is a lack of research outlining OGF dairy production practices, producer-identified research needs or social factors that affect OGF systems. The objectives of this study were to, with a group of OGF dairy producers, (1) assess information regarding current production practices and producer knowledge, and (2) identify agronomic and social factors that may influence milk production on OGF farms across the United States. A mail survey, focused on demographics, forage and animal management, knowledge, and satisfaction of their farm, was developed and distributed in 2019, with 167 responses (47% response rate). The majority of producers indicated they belonged to the plain, or Amish-Mennonite, community. Milk production was greater on farms that had Holstein cattle, as compared to farms with Jerseys and mixed breeds, and employed intensive pasture rotation. Furthermore, most producers reported the use of supplements such as molasses and kelp meal, which can improve milk production, but also increase feed costs. Producers who indicated that they were at least satisfied with their milk production also reported high levels of knowledge of grazing management and cow reproductive performance. Comparison of response data from plain/non-plain respondents revealed that those that did not identify as plain were more likely to utilize certain government programs, had different priorities and utilized technology more frequently. Based on these results, more research exploring financial and production benchmarks, effective communication strategies to reach OGF producers and methods to improve cattle production through improved forage quality is needed.

7 March 2024 in Renewable Agriculture and Food Systems
Verified
Journal Article
Open access
PDF file
EHEric Hatungimana
Eric Hatungimana
HDHeather M. Darby
Heather M. Darby
KSKathy J Soder
Kathy J Soder
SZSara Ziegler
Sara Ziegler
ABAndre F. Brito
Andre F. Brito
EBEdward Brummer
Edward Brummer
The viability of organic dairy operations in the United States (US) relies on forage production. The objectives of this study were to (1) assess producer and farm information regarding current forage production practices and producer knowledge gaps and (2) identify forage research and educational needs of organic dairy producers across the US. A survey was distributed to 643 organic dairy producers across the US, with 165 respondents (26% response rate). A focus group consisting of extension professionals, university researchers and staff, consultants, dairy industry representatives and organic dairy producers was also consulted for forage research needs. Results showed that approximately half (51%) of surveyed producers were somewhat satisfied with their forage production systems and sometimes experienced negative weather-related impacts on forage yield and quality. A majority (64%) of producers felt their knowledge to meet farm goals was adequate but they reported a lack of resources to implement this knowledge especially for balancing high-forage diets and selecting soil amendments. This study revealed that 54% of producers rely on peer experiences as information resources to make decisions on forage programs. Producer knowledge gaps included pasture renovation with reduced or no-tillage, forage mixtures that match their needs, and forage management practices aiming for high-quality forage. Based on the survey and focus group findings, forage research and educational activities should foster climate change resilience regarding forage diversity adapted to local and regional climatic conditions, improve forage quality, enhance economic returns from soil fertility amendments and pasture renovation, and introduce new forages and forage mixtures that suit economical, agronomical, and environmental needs.

1 February 2022 in Journal of Dairy Science
Verified
Journal Article
Open access
AAA. Ayers
A. Ayers
SZSara Ziegler
Sara Ziegler
HDH.M. Darby
H.M. Darby
SBS. Bosworth
S. Bosworth
JAJ.P. Alvez
J.P. Alvez
SGS.L. Greenwood
S.L. Greenwood
Variability of protein and energy supply from pasture during the grazing season is a primary factor that can influence milk production of grazing organic dairy herds in the Northeast United States. This study evaluated the effects of altering the crude protein (CP) content of dietary supplements included in dairy rations fed to grazing organic dairy herds, on milk production and composition. Six commercial organic farms participated in a 6-wk trial, consisting of a 2-wk baseline period and 4-wk experimental period. Farms were paired by their summer 2017 milk urea nitrogen profile, and farms within each pair were assigned by restricted random-ization to (1) continuation of their regular supplements (n = 3, control group, CON), or (2) supplement with altered CP as percentage of dry matter, formulated us -ing an organic barley and roasted soybean mix (n = 3, treatment group, TRT). Throughout the 6-wk trial, individual milk samples were collected at 2 consecutive milkings weekly, while pasture and supplement samples, pasture measurements, and management information were collected twice weekly per farm. Data were sta-tistically analyzed using the MIXED procedure of SAS (version 9.4, SAS Institute Inc.) for all parameters, and effects of treatment, week, and their interaction (treat-ment x week) were determined. The supplement CP (percentage of dry matter) during the baseline period was 13.5% for CON and 15.3% for TRT and 14.8% for CON and 19.3% for TRT during the experimental period. Milk production was 21% higher during the experimental period for TRT compared with CON (24.1 vs. 19.9 kg of milk per day, respectively). Milk production decreased for CON from wk 1 to wk 6 (23.6 vs. 20.4 kg of milk per day), whereas TRT maintained milked production from wk 1 to wk 6 (22.8 vs. 22.7 kg of milk per day). Milk composition was different between groups, with CON having higher fat percent (4.21 vs. 3.73%, respectively) and protein percent (3.15 vs. 3.05%, respectively) compared with TRT for the 6 wk. The milk urea nitrogen concentrations were similar between TRT and CON for the baseline period (11.9 vs. 12.1 mg/dL) and the final week of the experimental period (14.5 vs. 14.2 mg/dL). Although the effects of different diet CP fractions, particularly rumen unde- gradable protein and soluble protein, must be further delineated, these results indicate that altering the CP content of dietary supplements fed to grazing organic dairy cattle during the summer period in the Northeast US could be a useful mechanism to maintain milk pro- duction.

17 December 2025 in Sustainability
Verified
Journal Article
Open access
PDF file
QWQingbin Wang
Qingbin Wang
SZSara Ziegler
Sara Ziegler
SFSarah Flack
Sarah Flack
HUHakan Unveren
Hakan Unveren
AAAvery Anderson
Avery Anderson
HDHeather Darby
Heather Darby
While there is very limited information on the cost of production (COP) for the emerging 100% grass-fed organic dairy sector, this study (1) estimates the COP using primary data collected from on-farm surveys, (2) assesses the correlation between COP and key production and management factors, (3) examines how land, feed and labor efficiency, and production scale affect the COP, and (4) derives recommendations for enhancing the economic efficiency of grass-fed organic dairy farms. Data collected via annual surveys in the Northeastern United States from 2019 to 2022 were analyzed through descriptive statistics, correlation analysis, hypothesis tests, and regression analysis. At an average cost of USD 45.91 per hundredweight equivalent of milk, the marginal impacts of the cows managed per full time equivalent labor and milk sold per cow on the COP were −USD 0.166 and −USD 0.003, respectively. Conversely, the COP increased by USD 1.44 when the crop acres per cow increased by one unit, and the COP of small farms with less than 45 cows was USD 6.20 higher than other farms. As farms are significantly different in resource endowment and other factors, the strategies for reducing the COP and improving the economic returns should be identified for individual farms. However, our analyses highlight the importance of enhancing labor efficiency in forage production, land management, milking and feeding, improving herd management and optimizing nutrition and dry matter intake to support high milk productivity. This study may help existing grass-fed dairy farms improve their farm management and reduce COP and help prospective farms assess their suitability for transitioning to grass-fed operation.