TECHNICAL BULLETIN 78 ISSN 0070 - 2315

THE EFFECT OF REARING TYPE ON THE PRE- AND POST-WEANING LACTATION PERFORMANCE OF CHIOS SHEEP

AND THE GROWTH RATE OF THE LAMBS

M. Hadjipanayiotou and S Economides

AGRICULTURAL RESEARCH INSTITUTE MINISTRY OF AGRICULTURE AND NATURAL RESOURCES

NICOSIA CYPRUS

SEPTEMBER [986

THE EFFECT OF REARING TYPE ON THE PRE- AND POST-WEANING LACTATION PERFORMANCE OF CHIOS SHEEP

AND THE GROWTH RATE OF THE LAMBS

M. Hadjipaoayiotou and S. Economides

SUMMARY

Two experiments. one with primiparous and one with mUltiparous Chios ewes, were designed to study the effect of rearing type (twin (11'1). single (SN) and no suckling (ON)) on the pre· and postweaning milk yield of ewes and the growth rate of lambs. Significant differences in the preweaning milk yield were found: TN (139.5 kg), SN (1157 kg), ON (765 kg). Pos[weaning (43·90 day) and 90·day milk yields did not differ between TN and SN ewes. Differences. however. were significant between ON and the other two treatments. There were differences between primiparous

and multiparous 11'1 ewes in their mothering ability. More (62.5 vs 27.0%) and longer (8 vs 4 days/lamb) suckling as­~istance was required by primiparous than multiparous ewes. Furthermore, lambs from multiparous ewes did not re­quire bOttle feeding or crossfostering (multiparous 0, primiparous 53%). Milk intake of single (62 kg) was higher than thai of twin-suckling (54 kg) lambs and of artificially reared lambs (55 kg). Males grew faster than females and con­~umed more milk and solid feed than female lambs. In both expeFiments, single suckled lambs grew faster than twin ,uckled and/or artificially reared lambs during the prewe3.ning period. Artificially reared lambs required the most,

and single suckling the least milk per kg weight gain. Single suckling is recommended for Chios ewes, especially yearl ­ings. for high tOtal and commercial milk yields, and to avoid lamb losses due to insufficient supply of ewe milk.

INTRODUCTION MATERIALS AND METHODS

Sheep milk production has been studied in North Animals. Two trials were conducted using 74

European countries, New Zealand and Australia as primiparous and 75 multiparous Chios ewes. Ewes

part of nutritional and breeding programmes aimed were allocated randomly at 2 days post-lambing to

at increasing lamb production. Economical sheep twin-nursing (TN), single nursing (SN) and no­

production in Mediterranean countries is mainly nursing (ON) treatments. Lambs in excess and those

based on the sales of lambs for meat and the mar­on (ON) treatment were at 2 days of age transferred

keting of milk for the production of cheese and to a lamb bar and reared artificially. All lambs were

other milk products. Thus every attempt to increase injected with vitamin E and Selenium at 3 and 21

commercial milk yields and at the same time achieve days of age, and were vaccinated against enterotox­satisfactory rearing of the lambs is of great aemia at 21 and 42 days.

Importance.

Diets and management, In the first experimentSeparation of lambs from their dams immediately (primiparous ewes) the artificially reared lambs

after birth with the objective to' increase commercial were offered a mixture of calf-milk (19% fat and

milk yield may result in lower total milk yield of 25% protein) and ewe-milk replacer (25.8% fat and

ewes (Louca, 1972). The effect of rearing type on 24.2% protein). In trial 2, lambs were given only

subsequent milk production may vary with breed. ewe-milk replacer (Provilamb-SLL, product of Pro­

Geenty (1979) reported that Dorset ewes suckling vimi B.V., Rotterdam Holland). In both trials milk

one or two lambs had similar postweaning milk pro­powder was reconstituted in the ratio of 1 part ofduction, but pre-weaning milk yield of ewes rearing powder to 4 parts of water (by weight). Milk re­

twins had been consistently higher than those rear­placer was offered ad libitum from 3 to 28 days of

ing singles. [ncontrast, Stern et a!. (1978) (cited by age, and at restricted quantities (1 L/lamb) untilGeenty, 1980) reported higher postweaning milk weaning at 42 days of age.production from twin-rearing t han single-rearing

ewes.

The feeding behaviour (number of lambs requir­These experiments were designed to study the ef­ ing nursing assistance, or extra milk because of in­

fect of rearing type on the pre- and post-weaning sufficient milk production of the dam) of naturally milk yield of Chios ewes and the growth rate of suckled lambs was recorded twice daily (08.00h and lambs. 14.00h) during the first two weeks of life. Lambs on

2

TN and SN treatments were allowed to suckle their dams continuously for approximately 28 days and were subsequently separated from their dams from 16.00 to 08.00h for a period of 14 days. All lambs had free access to pelle ted feed from separate feed­ers (20% crude protein on DM basis) from day 15 postpartum.

Following weaning, all lambs were offered the same concentrate mixture ad Libitum plus 100 g/lamb of alfalfa hay daily. The pelle ted lamb feed was composed (kg/ton) of 468 barley grain, 300 sor­ghum grain, 164 soybean meal, 50 wheat bran,S di­calcium phosphate, 10 limestone and 3 sodium chloride. A vitamin and trace element mixture was added (2 kg/ton) t<;> supply 6000 1. U. vitamin A, 1000 1.U. vitamin D 3, 8.5 I.U. vitamin E, 25 mg Mn, 1.75 mg 1,45 mg Zn, 30 mg Fe, 2 mg Co and 60 mg Mg per kg of concentrate mixture. Sexes were kept apart, and group feed intake was recorded weekly.

In both trials the ewes were housed by treatment in adjacent pens of 10-13 ewes per pen and fed in groups on concentrates and roughage. From lamb­ing to weaning all ewes were offered concentrates in mash form ad Libitum and 1 kg of roughage/head /day consisting of 0.5 kg barley hay (8.5% crude protein and 8.3 MJ of ME/kg DM) and 0.5 kg alfalfa hay (20% CP and 9.3 MJ of ME/kg DM). Over the period 43-90 days following weaning all ewes were offered 0.8 kg roughage/head/day con­sisting of 0.1 kg alfalfa· hay and 0.7 kg barley hay (experiment 1) or 0.2 kg alfalfa hay and 0.6 kg bar­ley straw (experiment 2) plus concentrate to cover the remaining maintenance (401 kJ/kg 0.73), and milk energy requirements (7.1 MJ of ME/kg milk of 6% fat). The ewe concentrate mixture was com­posed (kg/ton) of 492 barley grain, 330 sorghum grain, 107 soybean meal, 50 wheat bran, 3 dicalcium phosphate, 15 limestone and 3 sodium chloride. Two kg of the vitamin and trace element mixture used in the lambs' feed was added per ton of concentrate.

Measurements. Individual commercial milk yield was recorded every fortnight prior to weaning, and once weekly thereafter. Milk suckled by lambs (Y) was calculated from regression equations with liveweight gain (X I ) and weaning age (X 2 ) as vari­ables (Economides, 1984). Individual equations were used for each type of suckling (single or twin)

and sex combination of suckling lambs. Lambs were weighed at birth, at 28 days, at weaning and once. weekly during the postweaning (43-90 days) period. Ewes were weighed at lambing. at weaning and once every fortnight thereafter.

Analysis of data. Lamb peformance data from each trial were analysed by least squares procedures with unequal subclass numbers (Harvey, 1975). Data on ewe milk yield and live weights were analysed by one-way analysis of variance (Steel and Torrie, 1960). Differences among treatment means were tested using the Duncan's new multiple range test. Economic analysis of the data was carried out assuming a price of 72, 45 and 600 Cf/ton for con­centrates, roughage and ewe milk replacer, respec­tively, and 0.295 and 1.17 Cf/kg as the selling prices for milk and lamb 'bodyweight, respectively.

RESULTS

Four primiparous ewes on trial 1 and 5 mUltipar­ous ewes on Trial 2 suffered from mastitis or lost their lambs before weaning, and their data were ex­cluded from the results. Mastitis or death of lambs, however, did not seem to be associated I with treatment.

Ewe performance. Feed intake during the prewean­ing period was affected by treatment (Table I). Ewes nursing two lambs consumed more feed than SN ewes; and the latter consumed more than ON ewes.

In both trials. there were highly significant (P=O.OOl) differences between treatments for the 42-day milk yield (Table I). TN ewes produced more milk than SN ewes and the latter produced sig­nificantly more milk than ON ewes. Ninety-day and 43-to 90-day total milk yield (Fig. 1) did not differ significantly between TN and SN treatments. Differ­ences between ON and TN ewes for the 43-90 day milk yield were significant (P=0.05) only in trial 2.

Fifty three. percent of the twin suckling lambs born to primiparous ewes required additional milk (bottle feeding or cross fostering) because milk pro­duction of their dam was insufficient. Another 9.5% of the lambs required assistance in nursing mainly because they could not suck, although milk was av­ailable. Twenty seven percent of the twin lambi> born to multiparous ewes required assistance in

3

Table 1. The effect of type of rearing on the pre - and post - weaning perfonnance of Chios ewes.

Experiment I Experiment 2

Number of lambs suckling Number of lambs suckling

2(TN) I(SN) O(ON) SO 2(TN) l(SN) O(ON) SO

Number of ewes Body weight at lambing (kg)

42-day milk yield (kg)

90-day milk yield (kg) 43-90 day milk yield (kg)

Milk suckled (kg) 42-day marketable milk (kg)

90-day marketable milk (kg)

22(21 )' 49.6

126.4 a 186.9 a 59.0 ab

1020 244 c 84.0 b

24 51.J

102.l b 170.1 a 68.0 a

562 459 b

llJ.9 a

25 508 627 c

Il02 b 47.5 b

55 + 62.7 a

1102 a

52 22.1 381 2(1)

206 375

23 62.1

1522 a 2384 a

86.2 a 114 7

375 c 123 7 b

24 626

129.3 b 224 7 a

954 a

680 61.J b

156.7 a

23 62.1 915 c

156.0 b

645 b 54.5 + 91.5 a

1560 a

6.7 30.5

52.2 25.3

30.4

521

Feed intake (kg):

(a) until weaning: concentrate roughage

(b) from weaning to 90 days: co nce n t ra Ie roughage

92.0

360

68.0 35.0

82.0 360

67.0 360

70.0 32.0

58.0 34.0

95.0 34.0

98.0 380

<)1.0

34.0

97.0

360

760 350

730 36

* Number of ewes after 42 days

+ Reconstituted milk replacer

Table 2. The effect of type of rearing on the pre - and post - weaning performance of Chios lambs.

Experimenl I Expt.:rirncfll

Suckling regime Suckling regim..::

T..... in Single­ Arufi<:tal Twin Single Arllfiui,ll

Sex M F M F M F 5.0 M M F M SO

Number 01 lambs

Birth weIgh! (kg) 2~·day weight (kg) Weaning weighl (kg) 9O-day weight (kg) We:ight gain (g/d'y)

Birth 10 w.::aning We:aning 10 9? days Birth 10 90 days

Fet:d intake (kg) Birth to weaning

W(:aning to 90 days

Milk (0 gain r;){io

Feed (0 gain ralio

«.1-90 days)

22(21 )'

36 96

11.2 28.2

228 3)

274

)33 469

5..W

31.1

n 3.6 ~.<

II 7 2-1 5

1~9

~67

231

4~.1>

.J16

604

335

II -1.3

II I I •. ~

J l..:i

!52 349

304

5.J. ~

53.7 5.2.J

3.21

13 < I

10.7 142

25.6

228 2-lJ 231>

)7.9 -14.0 5.77

}s5

II •. 7

10.7 14.0 30.0

220

JJl 281

20

326

55.(1

6.'1

11

<.0 10.3 12.9 25.1.)

21U 271 2-lJ

49.0

.177

O.nT I 2T

LOT 3 n.sss

,lnTSS

-'-'SSS ).1SS5

~:'

<.1 12.1 Iq 1, ~

201> 40/' PI

504.7

01.6 ),J.J

1.16

21 ),1>

IU.)

134 27. r

2.)<

2H6 21>1

.54.1

52 5 .i.52

3.8.1

12 <.9

15.0 II.J.]

37.K

331> 3R7 364

70.0 61>.0 4.H~

J.54

iJ <.1>

12.K 16.5 31.3

285 308 297

65.7 57.6

5.5.J

3.90

12 -I.S

II.) 1<.7 .11.3

2-11

)46

~97

5.1.6

3.51

12 J.9

III I 1.'.:' 27 I

229 2~(J

2)7

:'.Jj

.J7.9

.J ..W

.L51

O.l>lT.SS

I2lTl.SS 1.6lTlSS

.\IJTlTSSS

J1T1T.SSS 4IlT.SSS 3IlT.SSS

M = m;)lt's F ::: females ~ Nurnher of lambs after wCiinlng

T rearing. effect (P~"'ll 0:') '. TT rt:Clnng dfec( (P=(UlI)

rrr rt:'Jring cfft:ct (P=O.OOI)

S ~c., effect (P=O.05l S5 sex elkn (P~O.OI)

SSS ~t::~ ('lkl..·' (P=tl.(Xlll

4

Table 3. Feed costs and returns (0) per experimental ewe over the 90-day experimen­tal period.

2

Primiparous ewes

Lambs suckling/ewe

0 2

MUltiparous ewes

Lambs suckling/ewe

0

Feed costs Ewe

Concentrates Roughage

Lamb Milk replacer Concentrate

11.52 3.20

6.12

10.7J 3.24

6.60 331

3.46+

922 297

13.20 6.91

13.90 3.2-1

770

13.54 315

6.60 -1.68

-1.28+

10.71 3.20

13.20 8.56

Total costs

[ncome Milk (90 days) Lambs (90 days)

20.84

2478 52.30

27.34

33.63 27A9

26.77+

32.30

32 ...15 53.5..1

24.84

3658 62.60

32.25

-1632 3387

28.'2 +

35.69

45.43 5704

Total Income 77.08 87.89 85.99 99.18 108.71 102.47

Income minus feed costs 562..1 00.55 SH9 7·U..1 76.-16 6678

+ The second lamb was reare'd artili<:i,illy

nursing but none at the iambs required additional milk. None of the single lambs required any addi­tional milk.

Lamb performance. Milk intake of single lambs was higher than that of twin-suckling lambs (single 621, twins 54.1 kg/Iamb) and males consumed slightly more milk than females (males 58.6, females 55.2 kg/lamb). Solid feed intake was also higher in males than in females during the post-weaning period (Table 2). There were no differences in solid feed intake of lambs between treatments during the pre­or post-weaning period.

Sex had a significant effect (P=O.O I) on growth rate. Males grew faster than females throughout the experiment. In both experiments, single suckled lambs grew faster than twin suckled and/or artifi ­cially reared lambs during the preweaning period. In experiment 2, preweaning growth rate of twin suckl­ing lambs was greater (P=O.05) than that of the arti ­ficially reared lambs. Differences in experiment I, however, were insignificant. Type of rearing did not affect postweaning growth in experiment 1. In ex­

21.

>­ro 2.0~ ...

'" ~

0, -'" 1.6

:.:! '" >- 1.2 ~

E O.B

.<1 2 E'" E 0.1, <>------0 0 u

0 2 6 8 10 12 14

Fig.t. Effect of rearing type (0 twin; x single: • 110

suckling l<lmbs) on the pre and post - we<ln­ing commercial milk yield of Chios ewes.

5

periment 2, however, growth rate from weaning to 90 days and from birth to 90 days of age was poorer in the artificially reared as compared to the twin suckled lambs.

Artificially reared lambs required the most and single suckling the least milk per kg weight gain. In expenment I, reconstituted milk replacer required per kg weight gain was greater than that required in experiment 2.

The difference between feed costs and. income was greater for single suckling ewes followed by twin suckling ewes, the difference being greater for primiparous than multiparous ewes (Table 3).

DlSCUSSlON

In line with Lawlor et a!. (1974) and Louca (1972), the non-suckling ewes (ON) produced more marketable milk from lambing to weaning than th­ose that were suckled. The reduction in yield after weaning (7 to 13 weeks) was' higher in the TN (11.5%) than in the SN ewes (8.2%). During the same period ON ewes had the lowest percent reduc­tion in milk yield.

In experiment I, twin-suckling ewes produced (prior to weaning) on average 1.1 and 1.7 times the daily milk yield of single and no-suckling ewes, re­spectively. In experiment 2, the corresponding val­ues were 1.06 and 1.53. These findings are in agree­ment with Economides (1980), Hadjipanayiotou and Louca (1975), and Lawlor et a!. (1974), who re­ported higher preweaning milk yields of ewes suckl­ing one lamb compared to those suckling none. Dif­ferences in preweaning milk yield between twin and single-suckling ewes or cows have been reported (Nicoll, 1982; Maxwell et aI., 1979; Treacher, ]978).

In .Iine with Geenty (1979), ewes suckling single and twin lambs had similar postweaning milk pro­duction. It appears, therefore, that this effect did not carryover into postweaning milk production, although Stern et a!. (1978) (cited by Geenty, 1980) have reported higher milk production from twin­bearing compared to single-bearing ewes.

Very few ewes of any breed are capable of rearing triplet lambs efficiently (Large, 1965). The more fre­quent assistance in nursing and the bottle feeding re­

quired by lambs from primiparous compared to mul­tiparous ewes suggest that there are differences to

their ability to rear their lambs. Moreover, since primiparous ewes produce also less milk, there is a need to rear one/two lambs born as twins/triplets artificially. Finally, multiparous ewes can only rear two lambs. Differences in feed intake of ewes can be attributed to differences in milk yield.

In both experiments, single-suckled lambs had sig­nificantly higher preweaning daily gains that either twin-suckled or artificially reared lambs. The superiority in growth rate of the single-suckled lambs was attributed to their higher milk intake. In experiment 1, the similar growth rate of twin - suck­led and artificially reared lambs can be attributed to insufficient milk yield of pnmiparous ewes.

Differences between trials in the preweaning growth rate and conversion efficiency in artificially reared lambs were due to differences in the quality of the milk replacer used. Indeed, there were no sig­nificant differences in growth rate (ewe-milk 232 g, ewe-milk replacer 226g/day) between lambs offered (in a lamb bar) equal quantities (55 kg/lamb) of ewe milk of 4.5% milk fat content or reconstituted ewe milk replacer (provilamb-SLL) of similar fat content (Hadjipanayiotou, unpublished). The poorer post­weaning growth of artificially reared lambs (experi­ment 2) compared with the others must have been caused by housing and not by treatment.

In view of the high total milk yield of single­suckling ewes, the high 90-day commercial milk yield (similar to that of no-suckling), the higher pre­weaning growth of lambs, the limited suckling assist­ance required and the higher income over feed costs, single-suckling should be recommended in or­der to increase commercial milk yield and avoid lamb losses due to insufficient supply of ewe milk or inability of the lamb to suck adequate milk'.'

ACKNOWLEDGEMENTS

We thank C. Photiou, L. Hadjiparaskevas, S. Olympios, M. Theodoridou and C. Heracleous for skilled technical assistance. The ewe-milk replacer was donated by Provimi B. V., Rotterdam, Holland.

6

REFERENCES

Economides, S. 1980. Factors affecting the performance of ewes fed ad libitum until weaning, and the performance of their lambs Journal of Agricultural Science, Cambridge

95: 493-495.

Economides, S. 1984. Estimating milk yield of dual purpose ewes. Technical Bulleein 60. Agricultural Research In­stitute, Nicosia, 7 p.

Geenty, K.G. 1979. Lactation performance, growth and carcass composition of sheep. 1. Milk production, milk com­position, and live weights of Romney, Corriedale, Dorset, Romney X Dorset, and Dorset XRomney ewes in relation to the growth of their lambs. New Zealand Journal of Agricultural Research 22: 241-250.

Hadjipanayiotou, M.,and A. Louca. 1975. The effects of padlal suckling on the lactation performance of Chios sheep and Damascus goats and the growth rate of the lambs and kids. Journal of Agriculrural Science, Cambridge 87 15-20.

Harvey, W.R. [<)75 Lease squares analysis of data with unequal

subclass /lumbers. USDA ARS H-4 US, Governmeni Printing Office, Washington, D.C

Lawlor, M.J., A. Louc~., and A. Mavrogenis. 1974. The effect of three suckling regimes on the lactation performance of Cyprus fat-tailed, Chios and Awassi sheep and the growth rate of the lambs. Animal ProdllClion 18: 23'!­2'!9.

Large, R,V. 1<)65. The Artificial re"ring of lambs Journal 01 Agricultural Science, Cllmbridge 65' III 1-IUtL

Louca, A. 1972 The effect of suckling regime on growth rate and lactation performance of the Cyprus fat-tailed and Chios sheep. Animal Producr/on 15: 53-5'!

Nicoll, G,B. 1982. Effects of double ,udling at pa,ture. I. Cow performance, Animal Produuion 35: 385-3'!3.

Maxwell, T.J., JM. Doney, J.A Milne, LN. Peart. AJ F. Ru,­sel. A.R., Sibald, and D MacDonald. 1')7'). The effect of rearing type and prepartuf7l nutrition on the intake and performance of lactating Grcyface ewes at pasture. Journal of Agricultural Science, Cllmbridge '!2: 165-17-1

Steel, R,G.D, and J,H. Torrie [')6U. Pri/lciples II/ld Procedures

of Sealistics. McGraw-Hili, New York

Stern. D.. JH. Adler, H. Tagari and E Eyal. 1'!78. Response, of dairy ewes before and after parturition to different nutritional regimes during pregnancy. II Energy in­takc, body-weight changes during lactation and milk production. Annales de ZOOiechnie 27: 335-3",6 (Cited by K.G. Geenty. 1980. Dairy and suckled milk produc­tion of Dorset ewes. New Zealll/l/(Journal 0/ Experi­me/llal Agriculture 8: I') 1-197)

Treacher, T.T. 1978. The effects on milk production of the number lambs suckled and age. parity and ,ize of ewe. In European Association of AII/IIIIII PrOdUCliIJIl. Publi­

calion No. 23

7

Issued by the Press and Information Office, Ministry to the President, Nicosia

Printed by M. S. Zevlaris & Sons Ltd., Tel. ]11818, Strovolos - Nicosia

PIO 26/86 - 600