sheep

Requirements During Lactation

During the first few weeks following lambing, a lactating ewe requires about the same feed as in late gestation, provided she is nursing a single lamb. The requirements shown in table 3 are for a lactating ewe that is producing 3 pounds of milk per day.

If the lamb does not consume all the milk produced daily, the ewe produces less milk and uses any excess energy to store fat.

Ewes suckling twin lambs normally do not deposit fat because the nutrient supply (primarily energy) does not meet the requirements of the lactating ewe. For maximum rate and efficiency of lamb gains, separate ewes nursing twin lambs from those nursing singles and feed accordingly. It is practically impossible to provide high–producing ewes nursing twin lambs enough feed during lactation to prevent loss of body weight. From a practical standpoint, these ewes must have reserves of body fat to maintain high levels of milk production. It is imperative that high–producing ewes are of acceptable body condition prior to lambing.

Table 3. Daily nutrient requirements of sheep*

EWESc Maintenance
Body weight weight change/day dry matter per animala Energyb
TDN DE ME Crude protein Ca P Vitamin A activity Vitamin E activity
(kg) (lb) (g) (lb) (kg) (lb) (% body weight) (kg) (lb) (Mcal) (Mcal) (g) (lb) (g) (g) (IU) (IU)
50 110 10 0.02 1.0 2.2 2.0 0.55 1.2 2.4 2.0 95 0.21 2.0 1.8 2,350 15
60 132 10 0.02 1.1 2.4 1.8 0.61 1.3 2.7 2.2 104 0.23 2.3 2.1 2,820 16
70 154 10 0.02 1.2 2.6 1.7 0.66 1.5 2.9 2.4 113 0.25 2.5 2.4 3,290 18
80 176 10 0.02 1.3 2.9 1.6 0.72 1.6 3.2 2.6 122 0.27 2.7 2.8 3,760 20
90 198 10 0.02 1.4 3.1 1.5 0.78 1.7 3.4 2.8 131 0.29 2.9 3.1 4,230 21
Flushing—2 weeks prebreeding and first 3 weeks of breeding
50 110 100 0.22 1.6 3.5 3.2 0.94 2.1 4.1 3.4 150 0.33 5.3 2.6 2,350 24
60 132 100 0.22 1.7 3.7 2.8 1.00 2.2 4.4 3.6 157 0.34 5.5 2.9 2,820 26
70 154 100 0.22 1.8 4.0 2.6 1.06 2.3 4.7 3.8 164 0.36 5.7 3.2 3,290 27
80 176 100 0.22 1.9 4.2 2.4 1.12 2.5 4.9 4.1 171 0.38 5.9 3.6 3,760 28
90 198 100 0.22 2.0 4.4 2.2 1.18 2.6 5.1 4.2 177 0.39 6.1 3.9 4,230 30
Nonlactating—First 15 weeks gestation
50 110 30 0.07 1.2 2.6 2.4 0.67 1.5 3.0 2.4 112 0.25 2.9 2.1 2,350 18
60 132 30 0.07 1.3 2.9 2.2 0.72 1.6 3.2 2.6 121 0.27 3.2 2.5 2,820 20
70 154 30 0.07 1.4 3.1 2.0 0.77 1.7 3.4 2.8 130 0.29 3.5 2.9 3,290 21
80 176 30 0.07 1.5 3.3 1.9 0.82 1.8 3.6 3.0 139 0.31 3.8 3.3 3,760 22
90 198 30 0.07 1.6 3.5 1.8 0.87 1.9 3.8 3.2 148 0.33 4.1 3.6 4,230 24
Last 4 weeks gestation (130–150% lambing rate expected) or last 4–6 weeks lactation suckling singlesd
50 110 180 (45) 0.40 (0.10) 1.6 3.5 3.2 0.94 2.1 4.1 3.4 175 0.38 5.9 4.8 4,250 24
60 132 180 (45) 0.40 (0.10) 1.7 3.7 2.8 1.00 2.2 4.4 3.6 184 0.40 6.0 5.2 5,100 26
70 154 180 (45) 0.40 (0.10) 1.8 4.0 2.6 1.06 2.3 4.7 3.8 193 0.42 6.2 5.6 5,950 27
80 176 180 (45) 0.40 (0.10) 1.9 4.2 2.4 1.12 2.4 4.9 4.0 202 0.44 6.3 6.1 6,800 28
90 198 180 (45) 1.40 (0.10) 2.0 4.4 2.2 1.18 2.5 5.1 4.2 212 0.47 6.4 6.5 7,650 30
Last 4 weeks gestation (180–225% lambing rate expected)
50 110 225 0.50 1.7 3.7 3.4 1.10 2.4 4.8 4.0 196 0.43 6.2 3.4 4,250 26
60 132 225 0.50 1.8 4.0 3.0 1.17 2.6 5.1 4.2 205 0.45 6.9 4.0 5,100 27
70 154 225 0.50 1.9 4.2 2.7 1.24 2.8 5.4 4.4 214 0.47 7.6 4.5 5,950 28
80 176 225 0.50 2.0 4.4 2.5 1.30 2.9 5.7 4.7 223 0.49 8.3 5.1 6,800 30
90 198 225 0.50 2.1 4.6 2.3 1.37 3.0 6.0 5.0 232 0.51 8.9 5.7 7,650 32
First 6–8 weeks lactation suckling singles or last 4–6 weeks lactation suckling twinsd
50 110 –25 (90) –0.06 (0.20) 2.1 4.6 4.2 1.36 3.0 6.0 4.9 304 0.67 8.9 6.1 4,250 32
60 132 –25 (90) –0.06 (0.20) 2.3 5.1 3.8 1.50 3.3 6.6 5.4 319 0.70 9.1 6.6 5,100 34
70 154 –25 (90) –0.06 (0.20) 2.5 5.5 3.6 1.64 3.6 7.2 5.9 334 0.73 9.3 7.0 5,950 38
80 176 –25 (90) –0.06 (0.20) 2.6 5.7 3.2 1.69 3.7 7.4 6.1 344 0.76 9.5 7.4 6,806 39
90 198 –25 (90) –0.06 (0.20) 2.7 5.9 3.0 1.75 3.8 7.6 6.3 353 0.78 9.6 7.8 7,640 40
First 6–8 weeks lactation suckling twins
50 110 –60 –0.13 2.4 5.3 4.8 1.56 3.4 6.9 5.6 389 0.86 10.5 7.3 5,060 36
60 132 –60 –0.13 2.6 5.7 4.3 1.69 3.7 7.4 6.1 405 0.89 10.7 7.7 6,000 39
70 154 –60 –0.13 2.8 6.2 4.0 1.82 4.0 8.0 6.6 420 0.92 11.0 8.1 7,006 42
80 176 –60 –0.13 3.0 6.6 3.8 1.95 4.3 8.6 7.0 435 0.96 11.2 8.6 8,060 45
90 198 –60 –0.13 3.2 7.0 3.6 2.08 4.6 9.2 7.5 450 0.99 11.4 9.0 9,060 48
EWE LAMBS
Body weight weight change/day dry matter per animala Energyb
TDN DE ME Crude protein Ca P Vitamin A activity Vitamin E activity
(kg) (lb) (g) (lb) (kg) (lb) (% body weight) (kg) (lb) (Mcal) (Mcal) (g) (lb) (g) (g) (IU) (IU)
Nonlactating—First 15 weeks gestation
40 88 160 0.35 1.4 3.1 3.5 0.83 1.8 3.6 3.0 156 0.34 5.5 3.0 1,880 21
50 110 135 0.30 1.5 3.3 3.0 0.88 1.9 3.9 3.2 159 0.35 5.2 3.1 2,350 22
60 132 135 0.30 1.6 3.5 2.7 0.94 2.0 4.1 3.4 161 0.35 5.5 3.4 2,820 24
70 154 125 0.28 1.7 3.7 2.4 1.06 2.2 4.4 3.6 164 0.36 5.5 3.7 3,290 26
Last 4 weeks gestation (100–120% lambing rate expected)
40 88 180 0.40 1.5 3.3 3.8 0.94 2.1 4.1 3.4 187 0.41 6.4 3.1 3,400 22
50 110 160 0.35 1.6 3.5 3.2 1.06 2.2 4.4 3.6 189 0.42 6.3 3.4 4,250 24
60 132 160 0.35 1.7 3.7 2.8 1.07 2.4 4.7 3.9 192 0.42 6.6 3.8 5,100 26
70 154 150 0.33 1.8 4.0 2.6 1.14 2.5 5.0 4.1 194 0.43 6.8 4.2 5,950 27
Last 4 weeks gestation (130–175% lambing rate expected)
40 88 225 0.50 1.5 3.3 3.8 0.99 2.2 4.4 3.6 202 0.44 7.4 3.5 3,400 22
50 110 225 0.50 1.6 3.5 3.2 1.06 2.3 4.7 3.8 204 0.45 7.8 3.9 4,250 24
60 132 225 0.50 1.7 3.7 2.8 1.12 2.5 4.9 4.0 207 0.46 8.1 4.3 5,100 26
70 154 215 0.47 1.8 4.0 2.6 1.14 2.5 5.0 4.1 210 0.46 8.2 4.7 5,950 27
First 6–8 weeks lactation suckling singles (wean by 8 weeks)
40 88 –50 –0.11 1.7 3.7 4.2 1.12 2.5 4.9 4.0 257 0.56 6.0 4.3 3,400 26
50 110 –50 –0.11 2.1 4.6 4.2 1.39 3.1 6.1 5.0 282 0.62 6.5 4.7 4,250 32
60 132 –50 –0.11 2.3 5.1 3.8 1.52 3.4 6.7 5.5 295 0.64 6.8 5.1 5,100 34
70 154 –50 –0.11 2.5 5.5 3.6 1.65 3.6 7.3 6.0 301 0.68 7.1 5.6 5,450 38
First 6–8 weeks lactation suckling twins (wean by 8 weeks)
40 88 –100 –0.22 2.1 4.6 5.2 1.45 3.2 6.4 5.2 306 0.67 8.4 5.6 4,060 32
50 110 –100 –0.22 2.3 5.1 4.6 1.59 3.5 7.0 5.7 321 0.71 8.7 6.0 5,060 34
60 132 –100 –0.22 2.5 5.5 4.2 1.72 3.8 7.6 6.2 336 0.74 9.0 6.4 6,060 38
70 154 –100 –0.22 2.7 6.0 3.9 1.85 4.1 8.1 6.6 351 0.77 9.3 6.9 7,060 40
Replacement ewe lambse
30 66 227 0.50 1.2 2.6 4.0 0.78 1.7 3.4 2.8 185 0.41 6.4 2.6 1,410 18
40 88 182 0.40 1.4 3.1 3.5 0.91 2.0 4.0 3.3 176 0.39 5.9 2.6 1,880 21
50 110 120 0.26 1.5 3.3 3.0 0.88 1.9 3.9 3.2 136 0.30 4.8 2.4 2,350 22
60 132 100 0.22 1.5 3.3 2.5 0.88 1.9 3.9 3.2 134 0.30 4.5 2.5 2,820 22
70 154 100 0.22 1.5 3.3 2.1 0.88 1.9 3.9 3.2 132 0.29 4.6 2.8 3,290 22
Replacement ram lambse
40 88 330 0.73 1.8 4.0 4.5 1.1 2.5 5.0 4.1 243 0.54 7.8 3.7 1,880 24
60 132 320 0.70 2.4 5.3 4.0 1.5 3.4 6.7 5.5 264 0.58 8.4 4.2 2,820 26
80 176 290 0.64 2.8 6.2 3.5 1.8 3.9 7.8 6.4 268 0.59 8.5 4.6 3,760 28
100 220 250 0.55 3.0 6.6 3.0 1.9 4.2 8.4 6.9 264 0.58 8.2 4.8 4,700 30
Lambs finishing—4 to 7 months oldf
30 66 295 0.65 1.3 2.9 4.3 0.94 2.1 4.1 3.4 191 0.42 6.6 3.2 1,410 20
40 88 275 0.60 1.6 3.5 4.0 1.22 2.7 5.4 4.4 185 0.41 6.6 3.3 1,880 24
50 110 205 0.45 1.6 3.5 3.2 1.23 2.7 5.4 4.4 160 0.35 5.6 3.0 2,350 24
Early weaned lambs—Moderate growth potentialf
10 22 200 0.44 0.5 1.1 5.0 0.40 0.9 1.8 1.4 127 0.38 4.0 1.9 470 10
20 44 250 0.55 1.0 2.2 5.0 0.80 1.8 3.5 2.9 167 0.37 5.4 2.5 940 20
30 66 300 0.66 1.3 2.9 4.3 1.00 2.2 4.4 3.6 191 0.42 6.7 3.2 1,410 20
40 88 345 0.76 1.5 3.3 3.8 1.16 2.6 5.1 4.2 202 0.44 7.7 3.9 1,880 22
50 110 300 0.66 1.5 3.3 3.0 1.16 2.6 5.1 4.2 181 0.40 7.0 3.8 2,350 22
Early weaned lambs—Rapid growth potentialf
10 22 250 0.55 0.6 1.3 6.0 0.48 1.1 2.1 1.7 157 0.35 4.9 2.2 470 12
20 44 300 0.66 1.2 2.6 6.0 0.92 2.0 4.0 3.3 205 0.45 6.5 2.9 940 24
30 66 325 0.72 1.4 3.1 4.7 1.10 2.4 4.8 4.0 216 0.48 7.2 3.4 1,410 21
40 88 400 0.88 1.5 3.3 3.8 1.14 2.5 5.0 4.1 234 0.51 8.6 4.3 1,880 22
50 110 425 0.94 1.7 3.7 3.4 1.29 2.8 5.7 4.7 240 0.53 9.4 4.8 2,350 25
60 132 350 0.77 1.7 3.7 2.8 1.29 2.8 5.7 4.7 240 0.53 8.2 4.5 2,820 25

*Reprinted with permission from Nutrient Requirements of Sheep, 6th ed. © 1985 by the National Academy of Sciences. Courtesy of the National Academy Press, Washington, D.C.

aTo convert dry matter to an as-fed basis, divide dry matter values by the percentage of dry matter in the particular feed.

bOne kilogram TDN (total digestible nutrients) = 4.4 Mcal DE (digestible energy); ME (metabolizable energy) = 82% of DE.

cValues are applicable for ewes in moderate condition. Fat ewes should be fed according to the next lower weight category and thin ewes at the next higher weight category. Once desired or moderate weight condition is attained, use that weight category through all production stages.

dValues in parentheses are for ewes suckling lambs the last 4 to 6 weeks of lactation.

eLambs intended for breeding, thus, maximum weight gains and finish are of secondary importance.

fMaximum weight gains expected.