Animal Performance and Economics from Grazing Native Warm-season - - PowerPoint PPT Presentation

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Animal Performance and Economics from Grazing Native Warm-season Grasses Working Lands for Wildlife Workshop Southern Indiana Purdue Ag Center June 20, 2019 Patrick Keyser Center for Native Grasslands Management UT Beef and Forage Center

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Animal Performance and Economics from Grazing Native Warm-season Grasses

Patrick Keyser

Center for Native Grasslands Management UT Beef and Forage Center

Working Lands for Wildlife Workshop

Southern Indiana Purdue Ag Center – June 20, 2019

SLIDE 2

Grazing Research in Tennessee

Since 2009, we have completed numerous grazing studies using native warm-season grasses:

Weaned steers, 2009-2012
Bred dairy heifers, 2009-2012
Rotational vs. Patch-burn Grazing, 2014-2016
Eastern gamagrass vs. sorghumXsudan, 2013-2016
Comparison of 5 warm-season grasses, 2014-2016
Season-long, continuous grazing, 2015-2017
“Starving Heifer” study, 2015-2017

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Forage ADG (lb/d) AUD (days/ac) Gain (lb/ac) Switchgrass 1.74 172 435 Big blue/Indian 2.11 121 368 Eastern gamagrass 1.06 171 247

Animal Performance

(Steers) 2010-2012

93 – 115 days grazing per year ; 600 lb starting wt

Backus et al., 2017 Journal of Animal Science, 95:3143-3153

SLIDE 4

Forage Average Daily Gain (lb/d) May June July Aug Switchgrass 2.83 1.92 1.48 0.75 Big blue/Indian 2.83 2.57 1.76 0.87

How Does this Hold-up through the Season?

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Sustaining Gains during the Late Season

August 13 – 27 days rest October 6 – 40 days rest

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Bred Heifer Performance

Middle Tennessee REC, 2010 -2012; 1,050# Holstein heifers

Forage ADG (lb/d) Total Gain (lb/ac) Big blue/Indian 1.75 205 Switchgrass 1.37 198

Keyser et al., 2016 Journal of Agronomy, 108:373-383.

SLIDE 7

Eastern Gamagrass vs. Sudex

Bred Beef Heifers

500 1,000 1,500 2,000 2,500

Stocking (lb/acre)

E Gama Sudex No N applied on pastures for 5 years

Perennials:

always available
no decision on whether to plant
or when to plant annual
no annual establishment risk
no prussic acid/nitrate issues
more grazing days

ADG Days Beef/ac Gama 1.15 192 205 Sudex 1.63 81 129

P. Keyser, unpublished data

May 7 June 17

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Warm-season Grass Comparison

Total Gain per Acre, 2014-2016

Weaned heifers, 527 lb starting weight

K. Zechiel, MS thesis, unpublished data

50 100 150 200 250 300 Berm Crab BBIG Gama Switch

C C B AB A

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Season-long Grazing

Weaned Calves, 2015-2017

Grazing Strategy Steer ADG* (lb/day)

Continuous 2.17 Heavy Early 1.97

* O N/ac applied since at least 2011

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Heifer Development

250 300 350 400 450 Jan Feb March April May Sept Body weight, kg Fescue Big Bluestem Switchgrass Breeding

McFarlane et al. 2018. J. Animal Sci. 96:4633-4643. + protein supplement: 1.5#/day DDG (28% CP) 0.5#/day B/FM (72% CP)

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Body Weight at Breeding

55 51 48 5 10 15 20 25 30 35 40 45 50 55 60 65

Fescue BigBlue/Indian Switchgrass % Mature BW

McFarlane et al. 2018. J. Animal Sci. 96:4633-4643.

P <0.01

A B C

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Overall Pregnancy Rates

93 90 93 10 20 30 40 50 60 70 80 90 100 Fescue Big Bluestem Switchgrass Pregnancy rate, %

McFarlane et al. 2018. J. Animal Sci. 96:4633-4643.

P = 0.81

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Conclusions: Animal Performance

Generally very high based on these 7 UTIA studies:

– BB/IG > SG > EG – Excellent for backgrounding steers (except EG?) – Excellent for heifer development – Gains sustained for ~ 90 days with put-and-take management (rotational could improve late-season gains?) – Compare well with sorghumXsudan, crabgrass, and especially improved bermudagrass – Can even provide acceptable(?) dormant-season grazing

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Questions?

SLIDE 15

Native Grass Forage Economics

P. Keyser

Center for Native Grasslands Management and UT Beef and Forage Center Working Lands for Wildlife Workshop Southern Indiana Purdue Ag Center – June 20, 2019

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Economics Research in Tennessee

Since 2011, we have completed numerous economic analyses based on native warm-season grasses:

Budget-based assessment
Grazing weaned steers
Grazing bred dairy heifers
Comparison of 5 warm-season grasses
Model evaluating impacts of incorporating WSG into TF systems

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Natives = Low Input = Low Cost

Forage Hay Gain

($/ton) ($/lb)

Tall fescue 123

Sudex

83 0.75 Bermudagrass 75 0.54 Big bluestem 53 0.31

0 N in 5 years

Keyser et al. 2011. University of Tennessee Extension, SP 731-E.

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200 400 600 800 1000 1200

1 2 3 4 5 6 7 8 9 10

Dollars ($) Year(s) into production

No fertilizer

Cash-Flow Analysis (Ten Years)

Establishment costs plus replacement costs Replacement costs plus some production costs Production costs

Assumptions: $65/T for both fescue and NWSG hay; Fescue @ 2.4 T/acre and NWSG @ 4.0 T/acre

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Cash-Flow Analysis (Ten Years)

200 400 600 800 1000 1200

1 2 3 4 5 6 7 8 9 10

Dollars ($) Year(s) into production

Fertilizer during establishment @ 0-30-30

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Economics of Grazing Beef Steers

NWSG Beef Yield (lb/ac) Net Returns ($/ac)

West TN Switchgrass

229 $114

Big Blue/Indian

266 $148

E. Gama

248 $110

Middle TN Switchgrass

436 $342

Big Blue/Indian

370 $276

Lowe et al. 2015. Agronomy Journal 107: 1733–1740

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Cost of Gain for Grazing Heifers

$0.00 $0.10 $0.20 $0.30 $0.40 $0.50 Big bluestem/indiangrass Switchgrass

Keyser et al. 2016. Agronomy Journal 108: 373–383

Heifer development:

most expensive aspect of production
mainly feed cost (75%) for 30+ months w/o any return

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Warm-season Grass Comparison

Net Returns per Acre

Boyer et al. 2019. Agronomy Journal. In Review

$0 $20 $40 $60 $80 $100 $120 $140 $160 $180 $200 Berm Crab BBIG Gama Switch Net Return ($/acre)

BC C B AB A

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Net Returns for Five Summer Forages

17% 30% 67% 45% 3… 45% 45% 25% 31% 24% 38% 25% 9% 24% 73% 0% 10% 20% 30% 40% 50% 60% 70% 80% 90% 100% BI BG CG EG SG Probability

Probability of net returns being less than zero (red), between zero and $97 ac−1 (yellow), and greater than $97 ac−1 (green) Boyer et al. 2019. Agronomy Journal. In Review

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Impact of Perennial Warm-Season Grass Forages on Profitability

K. Brazil, Ph.D. dissertation, University of Tennessee

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Impact of Perennial Warm-Season Grass Forages on Profitability

K. Brazil, Ph.D. dissertation, University of Tennessee

Net present value over 10 years for three forage systems for spring- and fall-calving herds

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Conclusions: Economics

Natives have considerable economic benefit based

n these six UTIA studies:

– Relative to annuals, perennials more economically efficient – Natives require fewer inputs than Bermuda (or annuals) – Reduced inputs, combined with high yields/gains, make natives more profitable than other options – Natives’ advantage comes despite higher establishment costs – Model indicates adding natives makes operations more profitable (especially spring calving herds)

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