Establishing and Grazing Native Warm Season Grass: How Average Daily Gain and Internal Parasite Burden are Affected in Weaned Lambs

Final report for FS21-337

Project Type: Farmer/Rancher
Funds awarded in 2021: $2,723.00
Projected End Date: 03/31/2023
Grant Recipient: LeeDer Farm
Region: Southern
State: North Carolina
Principal Investigator:
Lee Holcomb
LeeDer Farm
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Project Information

Abstract:

As stated before, the problem of weaned lambs on pasture in the South is being severely infected with barber pole worms and affecting economic profitability.  This is through death loss of lambs, reduced weight gain, and getting to market later than planned.  Going to market later may affect economics of an operation due to less lambs going to market during prime market days such as ethnic holidays where prices tend to be higher per pound.

My proposed solution was to establish an approximate 1.2 acre Native Warm Season Grass (NWSG) pasture for weaned lambs.  The NWSG pasture consists of mostly Big Bluestem, Little Bluestem, and Indiangrass, and was planted on May 1st, 2021 using a No-Till Truax seed drill.  These native plants are more sustainable because they require minimal, if any, fertilization and are prolific growers once established.  They are also more drought tolerant, which is more common during hot summers in the South, because of deeper root systems.  Each species has different maturity rates and can help to establish vigorous growth during the entire warm season growing period.  NWSG’s grow more erect and the average growth point is around six inches above the soil surface.  The proposed research is that the taller growing grasses will allow the weaned lambs to graze at head height or slightly higher heights and avoid grazing so close to the ground where the Barber Pole Worm is more commonly found.  NWSG establishment is more common in cattle operations, but the proposed research is to investigate the effectiveness of their use in small ruminant operations, specifically with sheep.  The other proposed benefit of establishing NWSG pastures for weaned lambs is better weight gains both from reduced internal parasite burden and from grazing nutritious warm season grass versus cool season perennial forage Tall Fescue KY-31 variety.  It has been well documented that KY-31 variety Tall Fescue creates performance issues in livestock in climates such as the Southeast, due to the fungal endophyte located within the plant.  While the fungal endophyte gives the plant improved drought tolerance and survivability it also can cause poor livestock performance when it is consumed in large amounts by livestock.  Common symptoms in livestock are delayed hair shedding and heat stress, along with reduced weight gain while grazing this KY-31 variety during hotter summer months.  Giving the weaned lambs a grass that doesn’t cause these performance symptoms could lead to higher overall weight gains and growing marketable lambs  (60-75 lb. live weight) sooner.  This would be particularly helpful in hitting the target market dates around ethnic holidays such as Ramadan, commonly beginning and ending in the months of May and June.  The other economic benefit would be reduced lamb deaths due to reduced internal parasite burden.

The NWSG pastures were mowed in late January 2022 but were not burned with prescribed fire.  Contemporary Groups of lambs were placed in their selected pastures on May 15th, 2022 and grazed for approximately 8 weeks.  30 lambs participated in the grazing study.  Weights and Fecal Egg Count (FEC) were taken every two weeks during the grazing period.  Lambs were dewormed based on FAMACHA minimum score of 3 before treated.

Final conclusion of the grazing trial was no difference in FEC between lambs grazing cool season and NWSG grasses (FEC removed on lambs dewormed).  There were no statistical difference in weights between lambs grazing cool season and NWSG grasses.  The one trend in the study was there was a greater proportion of lambs grazing cool season grasses required deworming compared to those grazing NWSG grasses.  Both sires of the contemporary groups were from National Sheep Improvement Program (NSIP) flocks that have Estimated Breeding Values (EBVs).  Estimated breeding values for FEC were used to analyze results where relevant.  The more negative the FEC EBV the more the animal is resistant to internal parasite burden.  Once the FEC EBV's were analyzed in those lambs dewormed, there was a trend of greater lamb FEC EBV associated with greater deworming.

 

Project Objectives:

To test this hypothesis, it took two years to get final results.  The first year, 2021, was used to establish and maintain a Native Warm Season Grass (NWSG) mix pasture of roughly 1.2 acres in size.  Any cool season perennials and other weeds were eliminated from the existing pasture using Glyphosate treatment after grazing a cover crop of Oats and Crimson Clover.  One Glyphosate burn down was done April 2nd, 2021. Then a follow-up burn down of Glyphosate, along with pre-emergent Panoramic, was performed the day of planting on May 1st, 2021.  The NWSG mix was established via no-till methods and with help from Jason Smith, NC Wildlife Resource Commission Biologist.  Jason brings a wealth of NWSG knowledge and experience with many years helping producers establishing successful NWSG plantings in North Carolina.  He calibrated the seed drill according to NWSG seeding recommendations for the planting.  Jason has assisted with monitoring initial establishment growth and giving recommendations on any post planting treatment of weed pressure.  He recommended mowing in January 2022 and Prescribed Burn if possible in year two.  In Jason's experience the first year should be used for establishing a good root system and monitoring plant competition and its effects on survivability.  

In year two, 2022, a contemporary group of lambs were separated at weaning time.  One group was put on the established NWSG pasture and rotationally grazed with electric netting and temporary water tanks.  Another group was divided and rotationally grazed on our base cool season perennial KY-31 Tall Fescue with a mix of warm season annual forbs and weeds/grasses.  Electric netting was used and temporary water tanks.  Breeding groups of lambs were sired by at least two different Rams.  Contemporary groups were comprised of lambs from both sires to avoid bias and more inconclusive results due to poor on-farm testing setup. 

Lambs from both groups were weaned the same day, weighed on our W100 Gallagher weight scale for performance records, FEC sample taken, and then dewormed with Prohibit sheep drench before exiting the sheep working system.  All lambs were kept together as one group for 7 days and fed 1% body weight a 16% lamb grower feed, with coccidistat, to start everyone on an equal playing field.  The lamb grower feed were given 3 times in the 7 day equalization period.

After seven days, each contemporary group were weighed again and divided and placed in their respective NWSG or Cool Season Perennial pasture.  Each group were fed the same sheep mineral and have full access to cool, clean water from our pressurized watering system.  Actual weights were conducted every 2 weeks during the testing period, mainly on Saturdays or Sundays, due to our full-time job responsibilities.  During the grazing trial FEC samples were collected at two week intervals for both groups to see if there is any statistical difference between the two groups.  This resulted in six FEC samples during the testing period to hopefully show further proof of reduced parasite burden while grazing NWSG pastures in the immediate post-weaning period of lambs.  Lastly, forage will be tested for protein levels and TDN levels before lambs enter the pastures to get a representative comparison.

Cooperators

Click linked name(s) to expand/collapse or show everyone's info
  • Allison Brown - Producer
  • Johnny Rogers - Producer (Educator)
  • Jason Smith - Producer (Educator)
  • Dr. Andrew Weaver (Educator)

Research

Materials and methods:

As of May 1st, 2022 the NWSG pasture of Big Bluestem, Little Bluestem, and Indiangrass had been planted and gone through nearly one year of maturity.  Some cool-season weeds established in Spring of 2022, but Jason Smith advised not to use chemical treatment unless there were annual weeds that overshadowed the canopy of the newly emerging NWSG in Spring 2022. 

The two contemporary groups were divided with careful thought to avoid as much bias as possible.  A representative sample considering lamb sex, sire, age of dam, litter size, age of lambs as to not stack too many older ones against younger ones, and NSIP data for Fecal Egg Count.  Based on this criteria the two groups were arranged as fairly as possible.  Lambing season at LeeDer Farms yielded 30 lambs to go to test, while others were weeded out due to health status, death loss, or other reasons.

On May 15th, 2022 the two contemporary groups were separated into the two different pasture treatments, after spending the two previous weeks at the barn lot grazing and eating hay free choice and 16% lamb grower.  It took about two days for the warm season grass group to figure out how to graze the new species in their diet.  Before grazing the NWSG species they grazed summer annual weeds such as common ragweed, horseweed, and tall fescue five foot buffer next to the fence.  Cool season group is operating under a leader/follower grazing setup where the 15 cool season lambs graze a pasture, then are moved ahead and the ewe flock follows the previously grazed lamb pasture and grazes it down further to acceptable grazing height but not overgrazing.  To be successful in this endeavor, the pasture must be large enough to allow the cool season lamb group to preferential graze, but leave enough residue and plant material for the ewe flock the next day.

Forage samples were taken on May 23rd to begin comparison to see if there were any noticeable differences in Crude Protein and Total Digestible Nutrients.  

Under the direction of Allison Brown, Alexander CES Livestock Agent, I added a 18% protein block free choice to both contemporary groups in an effort to not limit growth due to poor forage growth of either forage stand.  

Lambs in both groups were moved daily to new pasture set up with temporary fencing which consisted of 9/35/12 Premier 1 Electronet.  Important note is the NWSG group grazed during the study on 1.2 acres total.  The cool season group grazed all of the cool season pasture acreage of roughly 8 acres during the two month study. 

Fecal samples were taken manually by the farmers Lee and Der Holcomb, then appropriately labeled, and refrigerated within 2 hours of collecting in a refrigerator.  Samples were then sent FedEx one day mail to Dr. Andrew Weaver at his N.C. State University address via an insulated package container with frozen packs to preserve samples.  Dr. Weaver and his graduate student, Nicole Valliere, then ran the fecal samples via the McMaster method.

Research results and discussion:

Lambs began grazing their respective pasture species on May 15th, 2022.  Summer of 2022 was relatively dry with high temperatures and rainfall was sporadic resulting in less than ideal pasture growth.  Rest periods, before returning to the same pasture, were the same for both contemporary groups at 21 days.  This was less than ideal but certainly put the lambs immune status to the test with internal parasite challenges.

In each group at least one lamb was removed from the study due to extenuating circumstances, which left the statistical analysis with 14 lambs per group.  One lamb died in the cool season group and one in the NWSG group got caught in electronet fence and suffered trauma and was treated for several days at the barn before being returned to the ewe flock.

Fecal samples were collected every two weeks at the handling facilities at the barn lot.  Lambs were walked to the barn with feed to entice them to make the trek back to the barn.  This needs to be taken into consideration as well, weight loss, due to being worked in the handling system every two weeks.  I had not accounted for this or consulted anyone about handling stress every two weeks and such an invasive procedure as fecal sampling via the rectum.  By the end of the study each group was used to the routine but the high temperatures and limited shade in the working facilities still accounted for a fair amount of stress.

FAMACHA score was used for the decision to deworm lambs or not.  With such a small statistical group, I waited until a lamb was a FAMACHA score of 4 before deworming and no longer including in any statistical final analysis.  Due to the internal parasite burden some lambs showed a FAMACHA score of 5 which is usually deadly.  Four cool season pasture group lambs were dewormed during the 70 day grazing study, and two NWSG pasture group lambs were dewormed.

Final conclusion of the grazing trial was no difference in FEC between lambs grazing cool season and NWSG grasses (FEC removed on lambs dewormed).  There were no statistical difference in weights between lambs grazing cool season and NWSG grasses.  The one trend in the study was there was a greater proportion of lambs grazing cool season grasses required deworming compared to those grazing NWSG grasses.  Both sires of the contemporary groups were from National Sheep Improvement Program (NSIP) flocks that have Estimated Breeding Values (EBVs).  Estimated breeding values for FEC were used to analyze results where relevant.  The more negative the FEC EBV the more the animal is resistant to internal parasite burden.  Once the FEC EBV's were analyzed in those lambs dewormed, there was a trend of greater lamb FEC EBV associated with greater deworming.

 

Participation Summary
2 Farmers participating in research

Educational & Outreach Activities

2 Consultations
1 Workshop field days
2 Other educational activities: Flyer for outreach and Power Point presentation for the field day.

Participation Summary:

44 Farmers participated
8 Ag professionals participated
Education/outreach description:

LeeDer Farms showed the final results and conclusion of this on-farm research through an in-person Field Day and Workshop on August 16th, 2022.  A flyer was developed for outreach and planning.  With the group of professionals involved with this SARE grant LeeDer Farms hosted at our farm.  Dr. Andrew Weaver and Lee Holcomb provided the Research Update via Power Point to all 52 attendees.  Questions were asked of Dr. Weaver and Lee Holcomb involving NSIP EBVs and overall herd management during the grazing study and overall.  Jason Smith, with NC WRC, covered NWSG establishment costs and management.   He went over the cost of establishment and common myths associated with NWSG grasses.  He answered questions from the attendees from a small ruminant standpoint and covered questions from multi-species grazers as well.

Johnny Rogers, with NCSU Amazing Grazing, spoke about the use of different temporary electric fence options and the advantages of rotational grazing from an internal parasite burden perspective for small ruminants.  Johnny is also a sheep producer as well and spoke to his own personal experiences and professional perspective from speaking across NC and the Southeast.

Allison Brown, NCCES Livestock Agent, spoke on Pasture ID & weed management in NWSG stands to complete the route from establishment to managing the NWSG stand.  Allison and her family have personal experience managing NWSG hay stands in Alexander County.  One hour of pesticide credit was given to those who hold a NC NCDA&CS Pesticide License.

The field day participants viewed handout presentations and we held live feedback for each presentation.  At the end of the field day, evaluations were handed out to those who were willing to fill them out.  Results were entered into Google Forms and shared with the presenters for feedback (https://docs.google.com/forms/d/1OuEO4_8apo_mM_wDWDXJkgoWMyrXDj6w9JzFZoZfrXM/edit?ts=639c1bbb#responses).

A Prescribed burn wasn't conducted in 2022, but LeeDer Farms did perform a prescribed burn in February 2023.  There were social media posts made about the burn and then later in April a progression of the NWSG growth since the burn were shared on social media.  Our hope is to continue to educate NC producers about NWSG and burning grasslands in pasture production.  

Learning Outcomes

52 Farmers reported changes in knowledge, attitudes, skills and/or awareness as a result of their participation
Key changes:
  • Temporary Fencing

  • Pasture and Weed ID

  • Managing Pasture Weeds

  • Establishing and Managing Native Warm Season Grasses

  • Sheep Grazing

Project Outcomes

1 New working collaboration
Project outcomes:

This project will hopefully contribute to agricultural sustainability due to the use of Native species.  Native species such as the Native Warm Season grasses (NWSG) used in this SARE grant are well suited to less fertile environments and require less nutrient inputs.  Environmentally this project has allowed a local example of how NWSG can perform in the Southeast and help more producers adopt this strategy.  We have used zero commercial fertilizer with the management of the NWSG and that is important to increasing the operations profit and water quality surrounding our farm.

More adoption of Native species will continue to benefit the environment and make it more economically profitable for Southeast producers.

Information Products

Any opinions, findings, conclusions, or recommendations expressed in this publication are those of the author(s) and do not necessarily reflect the view of the U.S. Department of Agriculture or SARE.