This study investigated the effects of different energy sources and levels on the growth, performance, and carcass characteristics of lambs. The main findings were: 1) Lambs fed an ad libitum whole shelled corn (WSC) diet had the highest average daily gain, best feed conversion ratio, and lowest feed cost of gain compared to lambs fed ad libitum alfalfa pellets or restricted WSC. 2) Lambs fed WSC diets had lower total digestive tract weights and higher hot carcass weights, backfat thickness, body wall thickness, and marbling scores compared to other diets. 3) WSC diets produced similar longissimus muscle areas

2. Effect of energy source and level and sex on growth,
performance and carcass characteristics of lambs
Small Ruminant Research
Volume 151, June 2017
Impact Factor: 1.148
J.R. Jaboreka, H.N. Zerbya, S.J. Moellera, F.L. Fluhartyb,
By Faisal A. Alshamiry

3. INTRODUCTION1
OBJECTIVES2
MATERIALS & METHODS3
CONCLUSIONS
RESULTS & DISCUSSION4
5
ATTACHMENTS6
CONTENTS

4. INTRODUCTION
• In the past, increasing the slaughter weights of lambs was a goal
of the American Sheep Industry (Harrison and Crouse, 1978).
• Recently the American Sheep Industry has had the difficulty of
balancing the heavy slaughter weights of lambs with
a desirable amount of fat thickness (American Lamb Industry Roadmap, 2013).
• The American lamb industry would also like to improve the
productivity of American lamb by improving the efficiency of gain
when compared with the cost of production.

5. • Restricted feeding of a Whole Shelled Corn (WSC)
diet or feeding a forage based diet can produce lamb carcasses with
less separable fat and similar amounts of separable lean tissue when
compared with carcasses from lambs offered ad libitum WSC.
• Feed restriction on a high concentrate diet or feeding a forage
based diet will result in more days on feed to finish lambs when
compared with lambs with ad libitum access to a high
concentrate diet (Murphy et al., 1994).

6. The objectives of this study were to
investigate the effects of energy source and
level, and sex on growth, performance, and
carcass characteristics of lambs.
OBJECTIVES

7. MATERIALS AND METHODS
 Ninety-six96Dorset×Hampshirelambs(♂♀)
 (Initial body weight; BW = 30.2 ± 2.6 kg).
 Lambs were individually weighed, ear tagged, and vaccinated
(WSC)alfalfa pellets
ad libitumad libitum
(WSC)

8. FEED
Sys. 3
TREA. 3
REPLICATE
24
4 WETHER PER PEN4 EWE PER PEN
MATERIALS & METHODS
44
44
44
44
44
44
44
44
44
44
44
44
96
48 ♀
TREAT. (1)
16
ad libitum
alfalfa pellets
TREAT. (2)
16
ad libitum
WSC
TREAT. (3)
16
85% WSC
48 ♂
TREAT. (1)
16
ad libitum
alfalfa pellets
TREAT. (2)
16
ad libitum
WSC
TREAT. (3)
16
85% WSC
2 FACTORS

9. • Feed samples of 100 g were collected every 14 days to determine (DM & DMI) and composition analysis
• Measurements BW, ADG, DMI & F:G every14 d.
• Eight lambs from each treatment were slaughtered for carcass quality measurements.
• The following carcasses measurements were recorded: LMA, BF, BWT.
• Weight before and after: (digestive tract).

10. a Contained >90.2% NaCl, 0.1% Zn, 0.8% Mn, 0.125% Fe, 0.01% I, and 0.002% Co, and 0.009% Se
Dietary Treatments
Ingredient
Alfalfa Pellets Ad Lib. WSC Limit-fed WSC
% Dry matter basis
Pelleted alfalfa 90 – –
Whole shelled corn – 85 80
Supplement
Ground Corn 6.32 – 2.35
Soybean meal 1 11.02 12.96
Urea 0.2 1 1.18
Limestone – 1 1.18
Monosodium phosphate 0.5 – –
Sheep salta
0.5 0.5 0.59
Vitamin A, 30,000 IU/g 0.01 0.01 0.01
Vitamin D, 3000 IU/g 0.01 0.01 0.01
Vitamin E, 44 IU/g 0.05 0.05 0.05
Selenium, 201 ppm 0.13 0.13 0.15
Amaferm, 141 g/kg 0.39 0.39 0.46
Ammonium chloride 0.4 0.4 0.47
A-V blend 0.5 0.5 0.59
Analyzed Composition
Crude protein, % 18.43 16.17 17.57
Starch, % 6.26 58.2 56.41
NDF, % 40.47 8.07 7.92
ADF, % 32.26 2.39 2.42
Calcium, % 1.23 0.42 0.52
Phosphorus, % 0.34 0.34 0.35
NEm, Mcal/kg 1.32 2.38 2.36
NEg, Mcal/kg 0.75 1.66 1.65
Table 1.
Nutrient composition
of lamb diets.

11. Statistical analysis
• The experimental design was a randomized complete block design with a 3 × 2
factorial arrangement of treatments to distinguish differences between diets (ad
libitum alfalfa pellets, ad libitum WSC, or restricted-fed WSC) and
sex (ewes and wethers).
• Analysis was performed using the MIXED procedure in SAS
• Initial BW, initial BW × diet interaction and final BW were used as covariates.

12. Results & discussion

13. Diet 1
Sex
Item Ad lib.
WSC
Ad lib.
Alfalfa
Limit-fed
WSC
SEM 2
Ewe Wether SEM 2
Initial BW, kg 30.10 30.14 30.22 0.983 29.31 31.00 0.80200
Off test BW, kg 62.2 62.4 62.1 1.10 60.66g
63.86f
0.89500
ADG, kg/d 0.372a
0.291b
0.310b
0.0191 0.323 0.326 0.01560
DMI, kg/d 1.440d
2.008c
1.274e
0.0197 1.538j
1.610i
0.01550
NEm intake, Mcal/d 3.421c
2.660e
2.999d
0.0438 2.951j
3.102i
0.03580
NEg intake, Mcal/d 2.388c
1.497e
2.098d
0.0305 1.943j
2.045i
0.02490
G:F, kg/kg 0.2583c
0.1456e
0.2416d
0.00509 0.2193 0.2111 0.00415
Feed cost of gain, $/kg 0.935e
4.624c
1.079d
0.0293 2.178 2.248 0.02390
Table 2. Least squares means of growth and performance of lambs.
a,b Diet means within a row without a common superscript letter differ (P < 0.05).
c,d,e Diet means within a row without a common superscript letter differ (P < 0.01).
f,g Sex means within a row without a common superscript letter differ (P < 0.05).
h,i Sex means within a row without a common superscript letter differ (P < 0.01).
1 Dietary treatments
2 The reported standard error of the mean is the greatest between the levels within the diet or sex treatment.
0
2
4
6
Ad lib.
WSC
Ad lib.
Alfalfa
Limit-fed
WSC
Cost $/Kg

14. Table 3. (1 -2) Least square means of visceral organ weights
of lambs.
a,b Diet means within a row without a common superscript letter differ (P < 0.05).
c,d Diet means within a row without a common superscript letter differ (P < 0.01).
e,f Sex means within a row without a common superscript letter differ (P < 0.05).
1 Dietary treatments
2 The reported standard error of the mean is the greatest between the levels within the diet or sex treatment.
3 Final BW is the weight collected at the abattoir just before harvest.
Diet 1
Sex
Item Ad lib.
WSC
Ad lib.
Alfalfa
Limit-fed
WSC
SEM 2
Ewe Wether SEM 2
Final BW, kg 3
60.2 57.5 58.6 01.49 57.2 60.4 1.19
HCW, kg 35.58
c
31.50
d
34.18
c
0.479 33.37 34.13 0.383
Dressing percent, % 60.34
c
53.09
d
57.99
c
0.805 57.36 56.92 0.65
Kidney fat, g 951
a
521
b
796
a
95.00 750 762 77.6
Rumen, g 937 992 933 58.60 918 990 47.7
Reticulum, g 133
b
191
a
140
b
11.90 153.8 157.8 9.66
Omasum, g 125.3
d
192.2
c
94.1
d
09.29 140.2 134.2 7.59
Abomasum, g 225 240 216 16.00 226 228 13.1

15. Table 3. (2 -2) Least square means of visceral organ weights of lambs.
a,b Diet means within a row without a common superscript letter differ (P < 0.05).
c,d Diet means within a row without a common superscript letter differ (P < 0.01).
e,f Sex means within a row without a common superscript letter differ (P < 0.05).
4 Total tract weight is the sum of the Rumen, Reticulum, Omasum, Abomasum, Small, Large intestine, and Cecum weights.
Diet 1
Sex
Item Ad lib.
WSC
Ad lib.
Alfalfa
Limit-fed
WSC
SEM 2
Ewe Wether SEM 2
Spleen, g 102.8 99.2 115.4 7.36 94.9
f
116.8
e
5.93
Small intestine, g 1032 1279 1034 82.4 1076 1154 67.3
Large intestine, g 509 731 466 72.6 553 584 59.3
Cecum, g 143 84 119 13.2 114 117 10.6
Liver, g 1085 1206 1056 41.1 1120 1111 32.3
Heart, g 262.1 247.5 252.0 7.42 259.9 247.7 5.95
Visceral fat, g 2230
a
1690
b
2130
a
117 1857 2180 93.8
Total tract, g
4
3120
b
3700
a
2990
b
132 3170 3370 107

16. Table 4. (1-2) Least squares means of carcass characteristics of lambs.
Diet 1
Sex
Item Ad lib.
WSC
Ad lib.
Alfalfa
Limit-fed WSC SEM2
Ewe Wether SEM2
Final BW, kg3 61.1 57.0 58.2 1.07 56.25
h
61.30
g
0.862
Shrink, %4 5.29
d
10.63
c
4.87
d
0.672 7.79 6.07 0.541
HCW, kg 35.87
c
32.04
d
34.32
c
0.519 32.71
h
35.45
g
0.418
Dressing percent, % 60.75
c
53.84
d
58.38
c
0.795 57.86 57.45 0.638
Kidney fat, g 1110
c
501
d
832
c
83.1 810 818 66.4
Backfat thickness, cm 0.96
c
0.52
d
0.89
c
0.548 0.84 0.74 0.442
Body wall thickness, cm 2.70
c
1.93
d
2.62
c
0.113 2.445 2.385 0.0909
a,b Diet means within a row without a common superscript letter differ (P < 0.05).
c,d Diet means within a row without a common superscript letter differ (P < 0.01).
e,f Sex means within a row without a common superscript letter differ (P < 0.05).
g,h Sex means within a row without a common superscript letter differ (P < 0.01).
1 Dietary treatments
2 The reported standard error of the mean is the greatest between the levels within the diet or sex treatment.
3 Final BW is the weight collected at the abattoir just before harvest.
4 Shrink refers to the weight lost from travel and lairage.

17. Table 4. (2-2) Least squares means of carcass characteristics of lambs.
5 Leg conformation, Carcass conformation, Lean color/quality, and Quality grade are based on a
numeric scale: 11 = avg. choice, 12 = high choice, and 13 = low prime.
6 Marbling score is subjective and based on a numeric scale: 300–399 = slight, 400 − 499 = small.
7 Yield grade = (((BF/2.54) × 10) + 0.4).
8 Percent boneless closely trimmed retail cuts = 49.94 − (0.085 × HCW) + (2.46 × LMA) − (4.38 × BF) − (3.53 × BWT).
Diet 1
Sex
Item Ad lib.
WSC
Ad lib.
Alfalfa
Limit-fed
WSC
SEM 2 Ewe Wether SEM 2
LM area, cm
2
17.56 16.04 18.54 0.669 16.88 17.88 0.54
Leg Conformation5 11.41 11.67 11.76 0.281 11.29 11.93 0.226
Carcass Conformation5 11.51 11.88 11.53 0.398 11.38 11.90 0.323
Marbling score6 448
a
353
b
461
a
23.0 422 420 18.6
Lean Color/Quality5 12.81 12.38 12.48 0.272 12.42 12.69 0.221
Quality Grade5 12.01 11.65 12.08 0.327 11.63 12.21 0.265
Yield Grade7 4.18
c
2.45
d
3.88
c
0.216 3.70 3.30 0.174
BCTRC, %8 44.52 46.49 45.42 0.460 45.41 45.54 0.371
a,b Diet means within a row without a common superscript letter differ (P < 0.05).
c,d Diet means within a row without a common superscript letter differ (P < 0.01).
e,f Sex means within a row without a common superscript letter differ (P < 0.05).
g,h Sex means within a row without a common superscript letter differ (P < 0.01).

18. Lambs offered ad libitum WSC had the greatest ADG, F:R and
a lower feed cost of gain .
Feeding WSC decreased the total digestive tract weight and greater
HCW, BF, BWT, marbling scores and YG measurements.
Feeding WSC diets produced numerically larger LMA and similar
amounts of boneless closely trimmed retail cuts.
CONCLUSION

19.  Feeding WSC can improve the rate and efficiency of
growth and performance of lambs and significantly reduced
feed cost when compared with feeding lambs alfalfa
pellets.
 Feeding WSC "unfortunately" increase total carcass
fatness when compared with feeding lambs alfalfa pellets.
OVERALL CONCLUSION

20. Thank you for attention

22. The United States Department of
Agriculture (USDA)
The percent Boneless Closely Trimmed
Retail Cuts (%BCTRC)

23. •‫هي‬‫طريقة‬‫احصائية‬‫يتم‬‫احتسابها‬‫عن‬‫طريق‬‫تقدير‬‫خط‬‫االنحدار‬‫و‬‫تهدف‬‫إلى‬‫تقليل‬‫مجموع‬‫االنحرافات‬‫الرئيسية‬‫أو‬‫األ‬‫خطاء‬‫الواردة‬
‫في‬‫النقاط‬‫التي‬‫تمت‬‫مالحظتها‬‫في‬‫خط‬‫االنحدار‬‫أي‬‫يتم‬‫التقليل‬‫من‬‫مجموع‬‫مربعات‬‫الفروق‬‫بين‬‫القيم‬‫الفعلية‬‫والقي‬‫م‬‫المحسوبة‬.
•‫ويمكن‬‫القول‬‫أيضا‬‫انها‬‫طريقة‬‫تقريب‬‫قياسية‬‫تستخدم‬‫لحل‬‫أنظمة‬‫المعادالت‬‫التي‬‫يكون‬‫فيها‬‫عدد‬‫المعادالت‬‫أكبر‬‫من‬‫ع‬‫دد‬‫المتغيرات‬.
"‫المربعات‬‫الدنيا‬"‫تعني‬‫بأن‬‫الحل‬‫الكلي‬‫يتجه‬‫نحو‬‫تصغير‬‫قيمة‬‫مجموع‬‫مربعات‬‫الخطأ‬‫الناتج‬‫عن‬‫حل‬‫كل‬‫معادلة‬.
Least squares
• This is a mean estimated from a linear model. In contrast, a raw or arithmetic mean is a simple average of your
values, using no model. Least squares means are adjusted for other terms in the model (like covariates), and are
less sensitive to missing data. Theoretically, they are better estimates of the true population mean.
• As a simple example, suppose you have a treatment applied to 3 lambs (experimental unit), and 2 observations
(samples) are collected on each. However, one observation is missing, giving values of (45, 36), (56, ), and (37,
41), where parentheses are around each lamb. The raw average is simply (45+36+56+37+41)/5 = 43, and note
the reduced influence of the second lamb since it has fewer values. The least squares mean would be based on
a model u + T + S(T), resulting in an average of the lamb averages, as follows.
• Least squares mean =[ (45+36)/2 + 56 + (37+41)/2 ] / 3 = 45.17 This more accurately reflects the average of the
3 lambs , and is less affected by the missing value.