Carcass characteristics of pasture vs. pen-fed meat goats

S. G. Schoenian1*, J.W. Semler1, D. L. Gordon1,

M.B. Bennett2, and D.J. O’Brien3

1University of Maryland College Park2West Virginia University

3Delaware State University

Background

• There is a lack of data pertaining to the performance, carcass characteristics, and economics of finishing meat goats in different production systems.

Procedure

• Consigners to the 2011 Western Maryland Pasture-Based Meat Goat Performance Test were asked to provide an additional goat for pen-feeding.

• The same consigner provided a second buck from the pasture test for slaughter comparison.

Procedure

Pen-fed (n=9) • 4.9 m2 zero grazing pen• Unlimited access to grass hay• Limit-fed grain once per day

– Avg. 1 lb. per head per day

• Free choice minerals w/Rumensin®

Pasture-raised (n=9)• Rotationally-grazed among six

2-acre paddocks of cool and warm season grasses

• No supplemental feeding• Free choice minerals w/Rumensin®

Data (6/10-9/15)

• Bi-weekly– Body weights– FAMACHA© scores– Body condition scores– Coat condition scores– Dag scores– Fecal egg counts

• October 1– Ultrasound

• Backfat• Rib eye area

Procedures

• After 112 days of consuming their respective diets, the goats were harvested to collect carcass data.

• Live weights were determined prior to transport to a custom-exempt slaughter-house (60 km away) for same day slaughter.

• Hot carcass weights were determined immediately after slaughter.

• Cold carcass weights were determined 6 days later when the carcasses were processed for data collection.

Procedures

• Kidney and heart fat was removed from the carcass and weighed.

• Carcasses were split between the 12th and 13th rib.

•Body wall thickness was measured with a metal ruler.

• Rib eye area was measured using a plastic grid.

Procedures

• Carcasses were completely deboned and separated into bone, fat, and lean, which were weighed to determine carcass percentages.

• A sample of the rib eye was sent to the meat lab at Ohio State University for analysis.

Data

MEASURED• Hot carcass weight (HCW)• Cold carcass weight (CCW)• Rib eye area (REA)• Body wall thickness (BWT)• KH fat (KH) weight• Fat weight• Bone weight• Lean weight

CALCULATED• Dressing percentage

HCW ÷ Live weight

• Percent KH fatKH ÷ CCW

• Percent BoneBone ÷ CCW

• Percent FatFat ÷ CCW

• Percent leanLean ÷ CCW

• YieldLean ÷ Live weight

Results

Trait Pasture PenLW, kg 26.0 ±0.94a 28.8 ±2.16a

HCW, kg 10.3 ±0.52a 12.9 ±1.23a

DP, % 39.4 ±1.15a 44.4 ±1.57b

CCW, kg 9.4 ±0.49a 12.3 ±1.25b

%KH 1.45 ±0.008a 2.64 ±0.025b

BWT, cm 0.41 ±0.04a 0.62 ±0.09b

REA, cm2 8.06 ±0.51a 10.11 ±1.11a

U-REA, cm2 6.42 ±0.23 7.91 ±0.82% Fat 2.14 ±0.08a 4.34 ±0.26b

% bone 42.28 ±1.10 37.15 ±1.56% Lean 54.80 ±1.16a 57.87 ±1.51a

Yield, % 19.78 ±0.09a 24.49 ±1.49b

Live and carcass weights (kg)

Live weight Hot carcass weight Cold carcass weight0.0

5.0

10.0

15.0

20.0

25.0

30.0

Pasture Pen-fed

a a a a a b

p < 0.05

Dressing percentage, %

0 1 2 3 4 5 6 7 8 930.0%

35.0%

40.0%

45.0%

50.0%

55.0%

Pasture-raised Pen-fed

Each number on the horizontal axis represents two goats from the same consigner.

Dressing percentage, %

Pasture-raised Pen-fed35.0

37.0

39.0

41.0

43.0

45.0

39.4

44.4

a b

p < 0.02

Carcass yields, %

% KH % Fat0.0%

0.5%

1.0%

1.5%

2.0%

2.5%

3.0%

3.5%

4.0%

4.5%

Pasture-fed Pen-fed

aa

b

b

p < 0.001

p < 0.001

Carcass yields, %

% Bone % Lean Yield, %10.0%

15.0%

20.0%

25.0%

30.0%

35.0%

40.0%

45.0%

50.0%

55.0%

60.0%

Pasture-raised Pen-fed

a aaa a b

p < 0.02

Rib eye area, cm2

Rib eye area, cm2

Carcass Ultrasound5.00

6.00

7.00

8.00

9.00

10.00

11.00

Pasture-fed Pen-fed

a a

Pasture Pen5.00

6.00

7.00

8.00

9.00

10.00

11.00

Carcass Ultrasound

Carcass vs. ultrasound

a b a b

p < 0.05

Conclusion

• Pen-feeding improved the carcass yield of meat goats in this preliminary study, but the economics of pen-feeding will vary by operation.

• A more formal study will be conducted in 2012 to evaluate the performance, carcass traits, and economics of pen vs. pasture feeding.

Thank you for your attention.