Ten dairy producers include forage brassicas into the diets of 750 grazing cattle, resulting in a reduction of 10.4 kg methane per cow and 780 kg methane per farm annually. Farmers reduce feeding costs by $1.50/cow/day and $6,750/farm/year by extending the fall grazing season by 2 months.
We hypothesize that brassicas will produce superior animal performance while emitting less methane per cow compared with annual ryegrass. Foliar glucosinolate concentration will be positively correlated with methane output reduction.
Year 1: (field plot and continuous culture fermentor studies)- Three forage brassicas will be used and include: ‘Inspiration’ Spring Canola, ‘Appin’ Forage Turnip, ‘Barsica’ Forage Rape. ‘KB Supreme’. Annual Ryegrass will be used as an annual grass control.
Year 2- Lactating dairy cows will be grazed on either: 1) brassica treatment plus perennial pasture, or 2) perennial pasture only (control).
In August 2016, 16 plots will be established and assigned 1 of 4 treatments (4 replications) in a completely-randomized block design. Treatments will be seeded at 4.5 kg/ha (brassicas) and 16.5 kg/ha (ryegrass) into a prepared seedbed located at the Russell E. Larson Agricultural Research Center at Rock Springs, Pennsylvania Furnace, PA.
Measurements will be taken for forage quality, foliar nitrate-N, forage yield, rising plate meter (RPM), and foliar glucosinolate concentration every two weeks. Fall sampling will end when weather no longer permits forage growth. Spring sampling will begin at forage green-up and continue until forages reach full maturity (seed-head appearance). Forage samples will be sent to Dairy One Forage Analysis Laboratory (Ithaca, NY) for determination of crude protein, fiber fractions, and nitrate-N. Glucosinolate concentration of freeze-dried forages will be determined through high performance liquid chromatography using an ultra aqueous C18 column (Restek Corp., Bellefonte, PA; 6). A 4-unit continuous culture system designed to simulate ruminal digestion and outflow to the small intestine will be used in a Latin-square design to evaluate ruminal fermentation and methane output for each forage treatment (18). Fermentors will be operated for four, 10-day periods (7-day adjustment and 3-day sampling). Each fermentor will be fed 75 g per day (22.5 g brassica and 22.5 g orchardgrass) in four equal feedings. On days 8 – 10, effluent samples will be collected for analysis of nutrient digestibility and methane output will be determined using a modification of methods described by Soder et al. (20).
In July 2017, 6 1.25-acre paddocks will be planted in mid- to late July at the UNH Organic Dairy. Three pastures will be planted to annual ryegrass and three pastures will be planted to one of the previously tested forage brassica species. The brassica species will be chosen based on nutritive value and in vitro methane mitigation data from Year 1. Approximately 45 days after planting, 20 multiparious lactating cows will be blocked based on milk production and randomly assigned to one of two groups. Each group of 10 cows will graze a pure stand of brassica or annual ryegrass for approximately 12 hrs per day (after afternoon milking until morning milking). All cattle will be turned out as one group into a pernnnial cool-season grass pasture during the day and baleage will be offered at milking. Baleage and grass pasture will be adjusted so that brassicas do not exceed 50% of the daily DM intake, this is in order to prevent possible adverse effects on milk, milk production, and cattle. Pastures will be rotated daily, so that each pasture is grazed once every three days. The length of the grazing season will be dependent on forage growth; however, we estimate that it should be approximately 6 weeks long. Pasture intake will be determined by feeding an indigestible marker. Animals will have ad libitum access to water at all times.
Body condition score and weight, forage yield and quality, foliar glucosinolate concentration will be determined every 14 days. Forage samples will be sent to Dairy One Forage Analysis Laboratory (Ithaca, NY) for determination of crude protein, fiber fractions, and nitrate-N. Glucosinolate concentration of freeze-dried forages will be determined through high performance liquid chromatography using an ultra aqueous C18 column (Restek Corp., Bellefonte, PA; 6). Milk production will be monitored twice daily and milk composition including fatty acid analysis will be determined three times a week. Blood, urine, and fecal samples will be collected every 14 days and analyzed for glucosinolate concentrations and pasture intake determination. Additionally, an economic analysis of costs and profits associated with grazing brassicas will be performed. Forage characteristics, methane, glucosinolate concentration, animal performance, and economic data will be analyzed using Proc Mixed of SAS (Statistical Analysis Software, Carey, NC) using a Repeated Measures statement. Means separation will be determined using the LSMeans statement with α = 0.05. Additional regression analysis on the variation in methane output will be conducted and correlation coefficients for significant variables calculated using the Reg and Corr procedures of SAS.
Continuous culture fermentor study was completed- manuscript is currently under peer review with a scientific journal. Additionally, a second manuscript is currently under review that outlines an improved methodology for detecting individual glucosinolates in brassicas, which will have application in future research to determine which individual glucosinolates may impact animal health and performance.
The forage plot study data collection is complete. Data summarization and manuscript preparation in progress.
Year 2 (UNH study)- forage brassicas were interseeded into an existing perennial pasture in fall 2017 at the UNH Organic Dairy. However, stand establishment was poor. We will repeat the experiment in fall 2018, only this time we will kill off the perennial pasture to establish the brassicas. Even though the first seeding was not successful, this information is important because farmers are interested in maintaining perennial pastures but adding brassicas to those swards for extended grazing. This will help us develop improved recommendations for establishing brassicas.
No results yet.
Extension Educator cooperators (Dr. Jessica Williamson and Mat Haan) will disseminate information via webinars, written material,a and will incorporate results of this project into their recommendations to grazing farmers.
A webinar was presented by Dr. Leanne Dillard on forage brassicas.
Written material (fact sheet, trade journal articles, peer-reviewed journal articles) are in progress or forthcoming as this project progresses.
A farmer field day was held in Oct. 2017. On-farm field day held on the use of brassicas (including a demo plot of brassicas on a dairy farm). https://www.facebook.com/events/384258408660221/
Research presented at the 2017 American Forage and Grassland Council annual meeting.
Research presented at the 2017 Northeast Pasture Consortium meeting.
Research presentation at the 2017 American Society of Agronomy Conference.
Twenty farmers in PA participate in focus group interviews to help project team assess their knowledge about current brassica use.
Farmers were interviewed orally and with the use of a survey on knowledge, interest and questions regarding use of brassicas in grazing systems.
This data was summarized to help develop products, including a webinar, fact sheet, and trade journal article. Product development will continue during the life of the study.
Based on focus groups, online, printed, and technical journal articles are written to address agronomic and grazing management practices of use forage brassicas in dairy production
To date, 1 fact sheet, 1 trade journal article (Progressive Forage Grower) and 1 webinar have been deployed (all documented in products) to disseminate information to farmers.
Several peer-reviewed journal articles are in preparation for publication, as well as other applied material for farmer use.
Three hundred cattle producers learn about the uses of forage brassicas in dairy cattle production via articles in technical journals, online media, or printed media sources written and submitted by project team.
A fact sheet was developed and disseminated at field days (including our brassica field day), pasture walks, and large ag events such as Ag Progress Days (near State College, PA) where 50,000 people attend this 3-day event.
One hundred dairy producers and extension educators attend live or view a recorded webinar discussing agronomic, grazing, and environmental stewardship of forage brassicas in dairy production through the Penn State Extension Grazing Guides for Dairy Systems Webinar Series. Attendees will be asked to fill out a survey (including contact information) to determine any current or future brassica interest and stored feed costs
A webinar on forage brassicas was presented by Dr. Leanne Dillard in Jan 2017 (documented in products). Approximately 25 participants viewed the webinar live. The webinar was also recorded and is available online for addition dissemination.
Two hundred dairy producers and extension educators learn about brassica research at the USDA-ARS booth at AG Progress Days. Attendees will be asked to fill out a survey (including contact information) to determine any current or future brassica interest and stored feed costs.
A demonstration plot of various forage brassicas was planted and displayed at Ag Progress Days (near State College, PA) where 50,000 people attend this 3-day event. Information was disseminated, including our fact sheet. Investigators were present to answer questions. Surveys were collected from farmers.
Forty famers learn about methane mitigation potential (Year 1 results), planting, fertilization, grazing management, and soil health benefits of forage brassicas at field day/grazing demonstration conducted at producer farm located in Lebanon County, Pennsylvania. Attendees will be asked to fill out a survey (including contact information) to determine any current or future brassica interest and stored feed
A brassica field day was held at Blue Mountain View Farm on Oct 19, 2017. A demonstration field of forage brassicas was available for viewing during the pasture walk. Dr. Kathy Soder (USDA-ARS), Dr. Jessica Williamson (PSU), Mat Haan (PSU), and Matt Bomgardner (farmer host) presented information on establishment, management and challenges of forage brassicas, animal health and production, and economics of forage brassicas. Surveys were collected as well.
Project team follows up with contacts from articles, webinars, field days, and referrals and identifies twenty farmers that are interested in including forage brassicas on their farm
This milestone is ongoing as information is collected from and disseminated to farmers.
Ten of these twenty farmers utilize grazed forage brassicas (at least 1 acre/4 grazing cows) in their production system for the first time and submit establishment and grazing management plan to project team.
Ongoing milestone- too early in the project to have results for this one.
Project team follows up with primary beneficiaries identified in Milestone 7 in order to ascertain success and pitfalls of establishment and grazing of forage brassicas in a pasture-based dairy system
As with Milestones 7 and 8, this milestone is ongoing.
Milestone Activities and Participation Summary
No results yet.