Pertanika 12(1), 27-32 (1989)

Dietary Self-Selection by Laying HensOffered Choices of Feed

RAMlAH HAMID, R.I. HUTAGALUNG and P.N. VOHRNDepartment of Animal Sciences,

Faculty of Veterinary Medicine and Animal Sciences,Universiti Pertanian Malaysia,

43400 UPM Serdang, Selangor Darul Ehsan, Malaysia

Key words: Self - selection; choice-feeding; laying hen

ABSTRAKSatu kajian pemberian makanan jangka pendek telah dijalankan dengan ayam penelur dengan tiga per-lakuan (1'1-1'3). Tiga perlakuan makanan tersebut ialah makanan ayam penelur komersial (1'1, satu-pilihan), makanan ayam penelur komersial dan grit cengkerang tiram (1'2, dua-pilihan) dan campuranjagung, campuran mil kacang soya dan grit cengkerang tiram (1'3, tiga-pilihan) dengan menggunakan 20ekor ayam untuk satu perlakuan. Kajian ini juga melibatkan pemerhatian ke atas tiga jangka masa jJemberianmakanan iaitu dari 0800-1200 tgh., 1200-1600 ptg. dan 1600-0800 pagi. Makanan dan air minumandisediakan secara ad libitum. Ayam diberikan 15 jam cahaya. Pengambilan makanan, tenaga dan proteinadalah ketara tingginya untuk makanan ayam komersial dan adalah rendah bagi makanan dua perlakuanyang lain. Pengambilan kalsium adalah ketara rendahnya bagi jJerlakuan satu-pilihan dan tiga-pilihan. Bagisemua perlakuan, ayam lebih memakan makanan pada waktu jangka masa 1600-0800 pagi (40.8-45.8 %makanan dimakan), iaitu pada waktu lewat jJetang dan awal pagi. Pengambilan makanan adalah lebihkW'ang sama (26.2-29.7% makanan dimakan) bagi jangka masa antara 0800-1200 tgh. dengan 1200-1600 ptg. Pengeluaran telur, berat heseluruhan telur dan tuharan makanan adalah ketara baiknya untukperlakuan dua-pilihan dan tiga-pilihan dibandinghan dengan perlahuan satu-pilihan. Tidak ada perbezaandaripada segi berat telur di antara hetiga-tiga peTlakuan.

ABSTRACTA short telm dietary self-selection experiment (28 days) was conducted with laying hens fed three treatments(Tl-T3) consisting of a commercially available layerfeed (1'1, single choice), commercially available layerfeedand oyster shell grit offered separately (T2, two choices) and a com mixture, soyabean meal mixture and oystershell grit offered sejJarately (T3, three choices). Measurement offeed intake was divided into three feeding periods,from 0800-1200h, 1200-1600h and 1600-0800h. Feed and watel' were available ad Iibi tum. Hens were raisedundel' 15 hour jJhotoperiod. Feed, energy and protein intakes wel'e significantly greatel' on the commercial dietand lower in the othel' two treatments. Calcium intahe was significantly lower on the single choice and three-choice diets. In all treatments, the hens tended to consume more feed during the pel10d between 1600-0800h(40.8-45.8% feed consumed), that is very late in the evening and very early in the morning. Similar amountsoffeed (26.2-29.7% offeed consumed) were consumed between 0800-1200h and 1200-1600h. tggproduction,egg mass and feed conversion were significantly bettel' on the two and three-choice diets as compared to thesingle diet. There was no difJeI'ence in egg weight among the three treatments.

INTRODUCTIONHens have the ability to discriminate betweenfeeds on the basis of different contents of major

nutrients. Dietary selection by laying hens maybeinvolved with the bird's requirement for differ-ent nutrients at specific times of the day

'Department of Avian Sciences, University of California, Davis, California 95616.

RAMLAH HAMID, R.l. HCTAGAl.U;-\G A:'-JD r.N. VOHRA.

TABLE IDetails of treatments and feed ingredients offered

free-c.hqice to laying hens.

days. Feed intake measurements were dividedinto 3 periods per day and measurements werecarried out at 0800h, 1200h and 1600h for twoperiods of 7 consecutive days, that is, on days8 to 14 and days 22 to 28, in order to study thedaily pattern offeed intake throughout the day.Hens were adapted to the diets 14 days beforemeasurements were made.

Egg production and egg weight weremeasured daily. All data were subjected to ananalysis of variance and differences betweenmeans were determined using the Least Signifi-cant Test (Steel and Ton-ie 1980).

(Emmans 1977). It is widely accepted that lay-ing hens consume energy in excess of dailymetabolic requirements when offered highenergy complete diets (Morris 1968; Summersand Leeson 1976). This overconsumption,maybe due, in part to the hen's requirementfor specific nutrients according to the stage ofegg formation. Part of this pattern is due to thespecific appetite for calcium related to theperiod of shell calcification (Hughes 1972;Mangin and Sauveur 1974).

If all hens in a laying flock could be offereda feed which just met their nutrient require-ments, there would be a considerable saving inboth nutrients and cost (Emmans 1978;Hughes 1984; Cowan (et al.) 1978; Leesonand Summers 1978, 1979). An effective sys-tem of dietary self-selection is more likely to befound with a clearer understanding of the wayin which hens react to being given access to twoor more feeds, and the feeding period whenthere is a higher intake of feed. Therefore, ashort term feeding trial (28 days) was conductedto study the nutrient intakes and performanceof laying hens when offered choices of feeds.

Dietary treatment

TI-Single feedT2-Two-ehoice diet

T3-Three-choice diet

Source of feed

Commercial feed.Commercial feedOyster shell grits.CornSoybean mealOyster shell grits.

TABLE 2Composition of three-choice diet

RESULTSFeed intakes oflaying hens at the three feedingperiods over the 28-day experimental periodare given in Table 3. There was a significant

Corn mixture Soybean meal mixture

Ingredient % Ingredient %

Corn 97.95 Soybean meal 98.25KH~PO, 2.00 KH~POI 1.50Vitamin and 0.05 Vitamin and 0.05

mineral mix. mineral mixDL-Methionine 0.20

100.0 100.0

Calculated Composition:Corn mixture

9.95

4 1.~Oo

Soybeanmeal rnixwre

I ~.9(J

R.n0.190

Metaholizahle energy(VlJ/kg)

Crude protein (%)Calcium (%)

MATERIALS AND METHODSSixty hens of medium body weight, brown egglaying strain (Dekalb Amber Link), 40 weeks ofage were randomly allocated to three treatments(TI-T3). The treatments (TI-T3) and feedingredients offered free choice are given inTable 1. A commercially prepared diet whichwas offered to hens in treatments 1 and 2 hadthe following nutrient composition: 11.9 MJ/kg metabolizable energy (ME), 16% crudeprotein and 3.25% calcium. The compositionand calculated analysis of nutrients in dins fortreatment 3 is given in Table 2. The commer-cial feed and also the corn mixture and soy-bean meal mixture, which are sources of ener6'J'and protein, respectively, were offered in mashform. Feed and water were ayailable arllibitum.All the hens were provided with individual feedcontainers. The hens were housed in individualbattery cages in an open-sided, covered shed.The hens were given 15 hours photoperiod and3 hours supplemen tary ligh ting was provided atdusk (1830h).

Feed and oyster grit intakes were deter-mined every seven days over a period of 28

28 PERTA:'-JIKA \'OL 12 NO. I, 1989

DIETARY SELF - SELECTION BY LAYING HENS OFFERED CHOICES OF FEED

difference (P

RAMLAH HAMID, RI. HUTAGALUNG AND P.N. VOHRA.

TABLE 4Daily intakes of energy, protein and calcium of laying hens during the

three feeding periods as means for a 28-day period'

Feeding Periodutrient Total

Intakes 1600- 0800- 1200- SE Intake0800h 1200h 1600h

Treatment 1:ME (kJ) 628" 384' 361< 32.6 1373Protein (g) 8.45" 5.17" 4.85" 0.43 18.5Calcium (g) 1.72" 1.05' 0.98" 0.09 3.75

Treatment 2:ME (kJ) 490" 330" 345" 21.3 1165Protein (g) 6.60" 4.43< 4.64e 0.29 15.7Calcium (g) 2.56" 1.34' 1.53')( 0.24 5.43

Treatment 3:ME (kJ) 477b 324" 365' 14.0 1166Protein (g) 5.84' 3.37' 4.99" 0.03 14.2Calcium (g) 1.75' 0.97< 0.93"" 0.11 3.65

""Values in a row and column (of same variable) with diffe'-el1l superscripts are significantly different (P

DIETARY SELF - SELECTION BY LAYING HENS OFFERED CHOICES OF FEED

COWAN, PJ., W. MICHIE and OJ ROELL 1978.Choice Feeding of the Egg Type Pullet. Br. Poult.Sci. 19: 153-157.

CLASSEN, H.L. and T.A. SCOlT. 1982. Self-selectionof Calcium during the Rearing and Early LayingPeriods of White Leghorn Pullets. Poult. Sci. 61:2065-2074.

defined. When offered calcium separately, henstend to select a higher calcium intake evenwhen the food offered is high in calcium. Whenthey were offered separate sources of energy,protein and calcium, hens were able to selectcalcium to meet their requirement with mini-mum protein and ME intakes to support highegg production. In this study, hens also con-sumed more feed during the early hours in themorning and late in the evening. This is attrib-uted to their high requirement for energy andprotein for egg formation and high calciumintake for calcification and also to the coolerenvironment during these periods.

31

REFERENCES

lower feed intakes than hens fed single diet,which was a reduction of about 10% and 14.3%respectively as compared to the control offeredsingle choice. This reduction in feed intake wasgreater than that reported by Leeson andSummers (1978) which was only about 7%. Thereduction in feed intake was associated withreduction in energy and protein consumed andan increase in calcium intake, especially forhens on treatment 2. Evidence of an increasedfeed intake in an apparent attempt to maintaina higher calcium intake has also been reportedby Classen and Scott (1982).

The feed intake, ME and protein intakesof the hens for all treatments was greatest in thelate evening (1600-2100h) and early morning(0630-0800h). This may have been related toincreased requirement for nutrients for eggformation, as it was observed that 48% of theeggs were laid before 1OOOh, 38% between 1400-1600h and 14% after 1600h. This is similar tothe findings by Holcombe et at. (1976) whereincreased intakes of nutrients especially pro-tein were· recorded late in the afternoon. The EMMANS, G.C. 1977. The Nutrient Intake of Lay-oyster shell grit intake was increased duri!)g ing Hens Given a Choice of Diets in Relation toafternoon and late evening, that is during the Their Production Requirements. Br. />oult. Sci. 18:feeding period of 1200-1600h and 1600-0800h, 227-236.

which relates to the high calcium requirement EMMANS, G.c. 1978. Free-choice Feeding of Lay-for synthesizing shell late at night. This ing Pullets. In Recent Advances in Animal Nutrition,observation is similar to the finding of Smith W. Haresign and D. Lewis (eds) pp. 31-39.et at. (1972) and Hughes (1972). The high HOLCOMBE, D.]., D.A. ROLAND and R.H.calcium intake in treatment 2, which was about HARMS 1976. The Ability of Hens to Regulate45% higher than that for treatment 1 was Protein Intake when Offered a Choice of Dietsassociated with an increase in egg production Containing Different Levels of Protein. Poult. Sci.by 15%. Therefore, a separate feeding of a 55: 1731-1737.calcium source influenced egg production as HUGHES, B.O. 1972. A Circadian Rhythm of Cal-can be seen in treatments 2 and 3 and this cium Intake in the Domestic Fowl. Br. Poult. Sci.would depend on the composition of the 13: 485-493.

complete diet. HUGHES, B.a. 1984. The Principles UnderlyingAlthough hens fed on two or three choice Choice Feeding Behaviour in Fowls - with Special

diets consumed less feed, they produced a Reference to Production Experiment~. World'sgreater egg mass, due to the higher number of Poultry Sci. Joumal40 (2): 141-150.eggs produced. This finding is similar to that of LEESON, S. andJ.D. SUMMERS. 1978. VoluntaryLeeson and Summers (1979). Hens practising Food Restriction by Laying Hens Mediateddiet selection also utilised feed more efficiently Through Dietary Self-selection. Br. Poult. Sci. 19:(0.41 and 0.44) as compared to hens con-' 417-424.suming commercial diet only (0.32). This is in LESSON, S. and J.D. SUMMERS. 1979. Dietary Self-agreement with the findings of Leeson and Selection by Layers. Poult. Sci. 58: 646-651.

Summers (1979). LESSON, S. andJD. SUMMERS. 1980. Effect ofIn conclusion, the study shows that the Early Light Treatment and Diet Self-selection on

ability of hens to regulate their diet is not well Laying Performance. Poult. Sci. 59: 11-15.

PERTANIKA VOl.. 12 NO. 1,1989

RAMLAH HAMID, R.I. HUTAGALUNG AND r.N. VOHRA.

MaNGIN, P. and B. SAUVEUR. 1974. Voluntary Foodand Calcium Intake by the Laying Hen. Br. Poult.Sci. 15: 349-360.

MORRIS, T.R. 1968. The effect of Dietary EnergyLevel on the Voluntary Calorie Intake of LayingHens. Br.Poull. Sci. 9: 285-295.

SMITH, WoK, P.D. BALLARD, and H.Y. BIELLlER. 1972.The Calcium Appetite of the Hen. Proceedings ofthe Austmlasian Poultry Science Convention, pp. 49-54.

STEEL, R.G.D. andJ.H. TORRJE. 1980. P7-incipl.es andProcedures ofStatistics. 2nd. Ed. New York: McGrawHill Book Co.

SUMMERS, J.D. and S. LEESON. 1976. Energy andProtein Requirements of Laying Hens. Nutr. Rep.Int. 17: 87-91.

(Received 29 September, 1987)

32 PERTANIKA VOL. 12 NO. I, 1989