training lambs to be weed-eaters conditioning ovis airies for use in the biological control of...
Post on 19-Dec-2015
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Training Lambs to be weed-eaters
Conditioning Ovis Airies for use in the biological control of Brachypodium sylvaticum- a non-native bunchgrass
Ryan Scholz
Dr. Howard Meyers
Dr. Deborah Clark
Slender False Brome
• Brachypodium sylvaticum– “Class B” Invasive Species
• First reported as naturalized in 1939 near Eugene, OR
• Centralized in Willamette Valley
• Recently discovered in Josephine County and Northern California
Background
• Slender False Brome (cont.)– Native to Europe, Asia, Africa
Habitat• Common in shaded forest
understories
• Gradually moves into un-shaded regions
• Out-competes many native plants
Background
• Control– Spray
• Accord ® (Glyphosate)
• Velpar® (Hexazinone)
– Super-heated foam• Waipuna machine
– Mechanical Removal– Burning/ mowing
• Appears to be ineffective
Background
• Control (cont.)– Grazing
• Observations indicate grazing is effective
• Studies are underway to investigate this
• Appears to be relatively low on sheep palatability hierarchy
Hypothesis
• Lambs grazed on B. sylvaticum with their mothers prior to weaning will have an increased affinity for B. sylvaticum as adults when compared to unexposed sheep.
Experimental Design
• Pre-Trial Training– Treatment- Grazed on B.
sylvaticum– Control- Grazed on
standard pasture– All lambs grazing for 3
week training period• First 2 weeks with ewes
• Last week weaned
Experimental Design
• Confinement Feeding Trial- wethers– Offered fresh cut B. sylvaticum after overnight fast– To determine the relative preference for B.
sylvaticum after training
• Pasture Grazing Trial- ewes– Grazed on a series of plots containing B. sylvaticum– To measure:
• Relative preference in a pasture setting• Continued preference over extended period of time
Confinement Feeding Trial
• Procedure– Lambs removed from field at 4:00pm and
individually penned– ~250g B. sylvaticum placed in each feeder at
10:00am• Allowed to eat for 30 minutes• Removed from pens• Leftover and wasted B. sylvaticum collected and weighed
– Repeated following morning
• Conducted immediately following training and again one month later
96%
4%
Data- Trial 1
Treatment Control
57%
22%
21%
Total Eaten Not Eaten Waste
100.0g B. sylvaticum
62%11%
27%
Data- Trial 2
Treatment Control
57%
22%
21%
Total Eaten Not Eaten Waste
250.0g B. sylvaticum
Analysis
• Shows training to be effective– Treatment lambs ate
more– Observations indicated
treatment lambs to be less timid when eating
• Some conditioning occurred with control– Likely situational
conditioning
Treatment
Control
Pasture Grazing Trial
• Procedure– Lambs grazed on series of 100m2 plots containing
B. sylvaticum– Four 1m2 clippings taken before and after grazing
• Determine biomass composition• Determine amount biomass removed
– Grazing patterns will be recorded using time-lapse video surveillance system
– Forage consumption and grazing patterns analyzed using forage maps
Data
Pasture Trial- Day 1
0.0
50.0
100.0
150.0
200.0
250.0
Treatment Control
Wei
gh
t (g
)
Beginning
Final
Analysis
• Final Analysis not complete– Observations indicate
training to be effective• Treatment lambs
consumed more B. sylvaticum
• Treatment lambs spent more time grazing
• Trial cut short due to uncontrollable circumstances
Further Planned Research
• Pasture training study– Yearling trial– Study replication
• Bummer lamb study– Bummer lambs fed milk with B. sylvaticum
extract• Seed viability
– Digested seed tested for viability
Questions