Body Composition and Net Energy Requirements of Brazilian Somali Lambs

Figures & data

Figure 1. Relationship between the logarithm of heat production and metabolizable energy intake for all ram lambs [HP=2.379 (±0.64)+0.0005 (±0.0007)*MEI (r²=0.85; root mean square deviation=2.87; P<0.001)].

Table 1. Ingredients and chemical composition of the experimental diet.

Ingredient	ME levels, MJ/kg
	4.93	8.65	9.40	10.12	11.24
Tifton-85 hay	100	80	60	40	20
Concentrate^°	0	20	40	60	80
Corn meal	-	158.7	694.5	724.6	756.1
Soybean meal	-	806.5	285.3	248.8	225.9
Urea	-	30.0	12.5	11.2	5.0
Limestone	-	-	-	5.4	6.6
Dicalcium phosphate	-	-	-	-	0.07
Salt	-	4.0	7.0	9.3	5.0
Premix	-	0.8	0.7	0.7	0.6
Nutrient
DM, g/kg	920.2	920.0	920.6	920.0	919.5
Ash, g/kg DM	56.3	56.9	46.8	42.3	40.2
CP, g/kg DM	92.5	164.2	160.3	165.8	169.5
EE, g/kg DM	23.3	24.6	34.0	45.3	49.5
NDF, g/kg DM	721.8	601.1	473.5	343.4	212.4
TC, g/kg DM	827.9	754.3	758.9	746.6	740.8
NFC, g/kg DM	106.1	164.1	270.6	415.4	524.8
TDN, g/kg DM	347.8	576.8	608.8	668.5	745.0

ME, metabolizable energy; DM, dry matter; CP, crude protein; EE, ether extract; NDF, detergent fibre; TC, total carbohydrate; NFC, non-fibrous carbohydrate; TDN, total digestible nutrient.

°Ingredients in concentrated portion of the diets: Ca, 7.5%; P, 3%; Fe, 16.500

Table 2. Mean values of parameters for body weight, performance, intake and energy retention of Brazilian Somali ram lambs.

Parameter	ME levels, MJ/kg DM^°					SEM	P
	4.93	8.65	9.41	10.12	11.24		L	Q
IBW, kg	12.44	13.82	13.70	13.60	13.69	-	-	-
FBW, kg	15.73	21.70	24.23	28.71	26.49	0.876	<0.001	<0.001
SBW, kg	15.14	20.96	23.68	28.10	25.99	0.869	<0.001	<0.001
EBW, kg	11.55	17.09	20.30	24.54	22.89	0.848	<0.001	<0.001
ADG, g/day	34.23	73.74	101.24	150.84	126.49	22.721	<0.001	0.715
EBW gain, g/day	19.83	62.04	94.42	139.00	120.53	27.810	<0.001	0.522
DM intake, g/EBW^0.75.day	53.58	71.28	77.14	76.93	70.56	1.271	<0.001	<0.001
ME intake, kJ/EBW^0.75.day	523.63	895.02	1005.29	1074.26	1146.83	5.241	<0.001	<0.001
Daily retained energy, kJ/EBW^0.75.day	63.16	186.34	209.54	226.22	259.28	8.608	<0.001	<0.001
Heat production, kJ/EBW^0.75.day	460.47	708.68	795.75	851.34	887.54	1.417	<0.001	<0.001

ME, metabolizable energy; DM, dry matter; L, linear; Q, quadratic; IBW, initial body weight; FBW, final body weight; SBW, shrunk body weight; EBW, empty body weight; ADG, average daily gain. Reference values for body weight: IBW=13.53; FBW=13.53; SBW=13.00; EBW=10.44.

°Days to slaughter for each ME level (in parenthesis): - (4.93); 104 (8.65); 103 (9.41); 101 (10.12); 102 (11.24).

Table 3. Chemical composition of the empty body of Brazilian Somali ram lambs.

Parameter, g/kg EBW	Reference value	ME levels, MJ/kg DM					SEM	P
		4.93	8.65	9.411	0.12	2.69	å	L	Q
Water	586.25	591.34	559.06	561.15	524.315	56.70	2.26	0.628	0.520
Fat	158.81	214.67	241.38	250.95	295.13	250.49	3.12	0.739	0.636
Protein	188.98	186.76	196.48	190.53	190.21	189.24	0.32	0.198	0.187
Ash	65.95	45.28	41.98	35.37	23.76	38.46	1.03	0.809	0.729

EBW, empty body weight; ME, metabolizable energy; DM, dry matter; L, linear; Q, quadratic.

Table 4. Logarithmic equations to estimate fat and energy body contents and composition of Brazilian Somali ram lambs.

Parameter	Regression equation	r2	RMSE	P
Fat, g	Log10 fat=1.964 (0.113)+1.337 (0.088) log10 EBW	0.87	0.05	0.001
Energy, MJ	Log10 energy=0.804 (0.173)+1.233 (0.085) log10 EBW	0.97	0.12	0.001

RMSE, root mean square error: EBW; empty body weight.

Table 5. Estimates of the fat and energy contents at different body weight intervals in growing Brazilian Somali ram lambs in function of empty body weight.

BW, kg	EBW, kg	Fat, g/kg EBW	Energy, MJ/kg EBW
13.00	9.38	195.89	44.846
20.00	16.07	234.91	50.829
25.00	20.85	256.47	54.003
28.70	23.72	267.86	55.646

BW, body weight; EBW, empty body weight. EBW=3.048+0.956 BW.

Table 6. Regression equations to predict the contents of fat and net energy requirement for kg of empty body weight gain at different body weight intervals in Brazilian Somali ram lambs.

BW, kg	EBW, kg^°	Fat, g/kg EBWG^#	Energy, MJ/kg EBWG^§
13.00	9.38	261.91	55.276
20.00	16.07	314.13	62.652
25.00	20.85	342.96	66.563
28.70	28.72	358.19	68.588

BW, body weight; EBW, empty body weight; EBWG, empty body weight gain.

°EBW=3.048+0.956 BW

^#Y=123.128 * EBW^0.337

^§Y=7.857 *EBW^0.232.

Table 7. Net requirements of energy for body weight gain in Brazilian Somali lambs.

BW, kg	Daily gain, g
	100	150	200	250	300
	Energy, MJ/animal/day
13.00	0.93	1.39	1.85	2.31	2.78
20.00	1.00	1.51	2.01	2.51	3.01
25.00	1.07	1.60	2.13	2.67	3.20
28.70	1.10	1.65	2.20	2.75	3.30

BW, body weight.