The effect of supplementation of liquid and crystalline lysine to barley-distillers solids diet on the performance and carcass quality of pigs Jarmo valaja Valaja, J. 1992. The effect of supplementation of liquid and crystalline lysine to barley-distillers solids diet on the performance and carcass quality of pigs. Agric. Sei. Finl. 1: 359-567. (Agric. Res. Centre of Finland, Swine Res. Sta., SF-05840 Hyvinkää, Finland.) The response to dietary lysine of liquid or crystalline form was examined in pigs fed on cereal protein diets over the range of live weight from 25.0 to95.0 kg. Forty individually fed growing pigs (20 gilts and 20 castrated males) were allocated to four isonitrogenous diets consisting of barley, undehydrated distillers solids and a mixture of minerals and vitamins with lysine supplementation of 0.9 or 3.2 g pure lysine per kg DM in liquid or crystalline form to provide 7.1 or 9.1 g/FU total lysine, respectively. The pigs were given feed on a restricted scale twice daily. A high level of lysine supplementation significantly increased the growth rate and improved the feed conversion efficiency (pcO.001). A low level of lysine supplementation produced significantly less lean in carcass (p<0.05) and a smallerarea of eye muscle (p<0.001). The loss at slaughter (in relation to live weight) of the pigs on high level of lysine supply was significantly lower than that of the pigs on low level of lysine supply (p<0.05). No significant differences were found in the performance and carcass quality of the pigs between liquid and crystalline form of lysine except that the area of eye muscle of the pigs on liquid lysine diets was larger than that of the pigs on crystalline lysine diets (p<0.05). No interaction was found between lysine source and level ofsupplementation on the performance orcarcass quality. The results of this study showed that both sources of lysine supplementation were equally efficient in improving the performance of the pigs. Key words: growing pigs, lysine, crystalline, liquid, distillers solids, performance, carcass quality Introduction Barley is the main ingredient in pig diets inFinland and it may account for up to 85 percent of the diet depending on the type of feeding. Barley provides most of the dietary energy and half or more of the protein in pig diets. Lysine is generally considered the first limiting amino acid in barley based diets for pigs (Fuller et al. 1979a, 1979b). Therefore, addition of protein to barley diets has the dual objective of increasing the dietary protein and of correcting the imbalances in amino acid composi- 559 Agric. Sei. Fint. 1 (1992) https://www.c-info.fi/en/info/?token=WlQa2x86TqtwRbrQ.wj6MJ3qPnrgYHQWpDOnxfw.n1JB3RXsulbtzNafeFSd27xaC98VW-DKxGyCA-_cJPiF1FIoTjdEeSNF4TkGfH7YrYuvJLQrCWcPNuQ-I0RzJaNOaStZg4yxmyh59FcG-cSdUc8P0bxxTqFTYMAsnHwuhksLZs_Ayn_ADdsY8CHKdUGbfUWJVtvkN7O6e9uR43-GS2TY7lzbX_M5fJ5vIeGF84qmkslAPQzPdJoEMElvHJDPOfvT8WxduQeCuiWJhz4vY0FpIqpUNJny9gd5puvgS_db tion of barley protein, especially the lack of lysine. Barley distillers solids is a cereal protein feed derived through an integrated barley starch-ethanol process, and its amino acid composition reflects the amino acid composition of the whole grain. The level of lysine in distillers solids does not meet the requirement of growing pigs (NÄSI and Aimonen 1992).An adequate level ofamino acids in the diet can be achieved by increasing the total protein con- tent of the diet or by balancing the amino acid composition of the diet with synthetic amino acids. Progressive protein supplementation of the diet al- ways leads to excess of other amino acids which has to be catabolized and excreted with manure. On the contrary, the crude protein content of the pig feeds can be reduced by supplementation of synthetic amino acids to meet better the amino acid require- ment of theanimal (TAYLOR etal, 1979, NÄSI 1985, VALAJA 1992). Several experiments have been made to study the utilization of different forms of lysine in pigs. However, in most of reports comparison is being made between free and protein-bound lysine (FUL- LER etal. 1986, Susenbeth etal. 1991,MATRE and Home 1991), or between protein-bound lysine of different sources (Batterham et al. 1978, 1981. 1990). Only few studies deal with the utilization of different lysine products (Gruhn et al. 1982, LIE- BERT and Gebhardt 1984, NÄSI 1992). The pres- ent work was undertaken to study the effect of supplementation of lysine in liquid or crystalline form to barley-distillers solids diets on the perform- ance of growing pigs. Material and methods Forty growing Landrace and Yorkshire pigs weighing 25.0 (SE 0.36) kg on average were used in a performance trial. The pigs were allocated to five blocks on the basis of litter origin and sex. Two pigs from each block were assigned at random to one of four experimental diets. One pig was placed in each pen. Each diet was tested on five gilts and Table 1. Dietary ingredients (g/kg DM) and calculated chemical composition of the experimental diets. 12 3 4Diet Ingredient: Barley 818.6 822.4 812.1 798.9 Distillers solids 142.0 135.3 142.0 135.3 Liquid lysine - - 7.6 27.8 Crystalline lysine 1.1 4.1 - Mineral + vitamin mixture 1 38.3 38.2 38.2 38.0 Chemical composition: Crude protein, g/FU 156 156 158 164 Digestible crude protein, g/FU 135 135 136 140 Lysine, g/FU 7.1 9.1 7.1 9.17.1 9.1 7.1 9.1 Threonine, g/FU 6.9 6.8 6.8 6.7 Methionine + Cystine, g/FU 6.8 6.7 6.8 6.7 Feed unit (FU/kg DM)2 1.12 1.12 1.12 1.11 1 Supplied per kg DM: Ca g 200 75P NaCI " 103 Vitamin A 1000IU 3500 Vitamin D " 57.2 Vitamin E mg 1200 Se " 4 2 Feed unit (FU) =0.7 kg starch equivalent five castrated males. The four experimental diets were isonitrogenous and consisted of barley meal, barley distillers solids and an adequate amount ofminerals and vitamins to meet the nutritional requirements of growing pigs (Salo et al. 1990) (Table 1). Lysine was supple- mented to the diets either in a liquid or crystalline form. The liquid lysine was a product derived through fermentation ofbeet molasses by Brevibac- teriumflavum. strain V-5 (Beker et al. 1971). It was sterilized and dehydrated in a vacuum-vapour evaporator up to a DM content of 500 g/kg and stabilizedby adding hydrochloric acid up to pH 5.1. Commercially produced L-lysine monohydrochlo- ride (Eurolysine) was used as the crystalline lysine. The level of lysine supplementation to the diets was 0.9 and 3.2 g pure lysine/kg DM. Distillers solids were obtained by centrifugation of distillers sol- 560 Agric. Sei. Finl. 1 (1992) Table 2. Average chemical composition of the experimental feeds. Liquid Crystalline lysine lysine Feed Barley Distillers solids lysine Mean Min. Max. No. of observations I 8 1 1 140 236 520 990Dry matter, g/kg 887 I I'» 198 Crude protein, g/kg DM Ether extract." 530 432 592 497 ND 20 79 70 89 10 ND Crude fibre," N-freeextract," Ash," 62 19 10 25 ND 776 340 263 442 240 ND 23 67 46 100 150 ND Amino acids g/160gN g/!6OgN g/kg DM g/kg DM 117 79040 37 56Lysine 45 Threonine Methionine Cystine 39 40 36 44 8 414 ND 23 21 25 35 25 42 Histidine Leucine Isoleucine 43 18 13 22 66 75 69 84 12 35 51 43 59 8 7 7 Phenylalanine Arginine 51 59 53 70 60 45 36 52 ND = not determined übles from the Alko Ltd. Koskenkorva factory employing an integrated starch-ethanol process and using barley as raw material. The detailed descrip- tion of the integrated starch-ethanol production process has been presented by NAsi (1988). Linde- hydrated distillers solids were preserved with so- dium benzoate 3 g/kg and were delivered from the Koskenkorva factory weekly during the experi- ment. At the research station distillers solids were stored in a 1500 litre glass fibre container, with a propeller mixing the contents of the container for 15 minutes every two hours. The feed ingredients were analyzed by standard methods (Aoac 1984) and the amino acid composition was determinedby high-performance liquid chromatography (HPLC). Feed values were calculated using feed table values for barley (SALOet al. 1990) and digestibility coef- ficients reported by NÄSI and AIMONEN (1992) for distillers solids. The chemical composition of the feed ingredients is presented in Table 2. The pigs were housed in partially slatted pens with concrete floors and free access to water. Feed- ing was restricted to 1.3 - 3.0 FU/day/animal. Two basal feeds were compounded from barley, a mix- ture of minerals and vitamins and crystalline lysine for diets 1 and 2 and two basal feeds from barley and a mixture of minerals and vitamins for diets 3 and 4. The daily allowances of the basal feed and distillers solids (diets I and 2) or basal feed, distill- ers solids and liquid lysine (treatment 3 and 4) were weighed separately and mixed in a trough. Because of the variation in dry matter content of distillers solids the daily amount was adjusted weekly ac- cording to the dry matter analysis of each batch. The pigs were fed twice a day. They were weighed at two week intervals and feed consumption was recorded daily. The pigs were slaughtered at an average weight of 95.0kg. At slaughter the carcass weight was recorded and backfat and sidefat thick- ness, area of eye muscle, lean in carcass and in valuable cuts were measured (Kantakoe-eläin- ten... 1979). 561 Agric. Sei. Fin!. 1 (1992) Table 3. Performance and carcass quality of the pigs (LS means of the treatments are presented). Treatment 1 2 3 4 Sex Significance Lysine form Crystalline Liquid Lysine Sex SEM Gilts Castrated SEM Form Level Lysine level, g/FU 7.1 9.1 7.1 9.1 males No. of animals 10 10 10 9 19 20 Initial weight, kg 24.9 24.9 25.0 25.0 0.362 24.7 25.2 0.512 NS NS NS Final weight (corr.), kg 93.8 95.4 94.4 95.7 0.938 95.2 94.4 1.327 NS NS NS Carcass weight, kg 69.4 70.6 69.9 70.8 0.694 70.4 69.9 0.981 NS NS NS Loss at slaughter, % 27.0 25.5 26.1 25.4 0.397 25.6 26.4 0.561 NS * o Daily gain, g 732 832 754 852 16.63 776 807 23.52 NS *** o Days in experiment 94.6 85.5 92.5 82.8 2.203 91.8 86.2 3.115 NS *** * Feed consumption, kg DM/animal 197.6 176.6 194.9 176.4 3.698 190.6 182.1 2.615 NS *** * FU/animal 222.0 198.3 218.5 195.6 4.149 213.6 204.0 5.868 NS *** * kg DM/animal/day 2.09 2.07 2.11 2.11 0.020 2.08 2.11 0.014 NS NS NS FU/animal/day 2.35 2.32 2.37 2.36 0.022 2.33 2.36 0.031 NS NS NS FCE, kg DM/kg gain 2.87 2.51 2.81 2.50 0.047 2.71 2.63 0.033 NS *** o ", FU/kg gain 3.22 2.82 3.15 2.77 0.053 3.04 2.95 0.075 NS *** o Back fat thickness, mm 24.1 23.1 24.8 24.7 1.200 23.3 25.0 1.697 NS NS NS Side fat thickness, mm 17.5 16.0 18.0 17.2 1.111 16.6 17.6 1.571 NS NS NS Eye musclearea, cm2 36.5 38.7 37.4 41.0 0.701 39.2 37.6 0.991 Lean in valuable cuts, 80.3 81.6 80.0 80.7 0.569 81.6 79.8 0.805 NS o ** % Carcass lean, % 54.2 55.3 53.8 54.6 0.473 55.0 54.0 0.669 NS * * Significance of lysine level (treatment 1 and 3 vs. 2 and 4); Significance of lysine form (treatment 1 and 2 vs. 3 and 4) Significance: NS =non-significant, o = p0.10). No interactions were found be- tween lysine level and form of supplementation in the performance of the pigs. Regression equations were calculated for daily gain and feed conversion efficiency as a function of lysine level in the diets based on the assumption of linear response of lysine between the two levels. Because no differences were found in the perform- ance of the pigs between the lysine sources, pooled data was used in the calculation. The regression equation for daily gain (g/d) (Y) as a function of lysine level in the diet (g/FU) (X) was Y = 409 (SE 77.5) + 46.9 (SE 9.53) * X, R 2=0.40. The regression equation for feed conversion effi- ciency (FU/kg gain) (Y) as a function of lysine level (g/FU) (X) was Y = 4.54 (SE 0.238) - 0.19 (SE 0.029) *X, R 2=0.53. Sex also had a significant influence on the perform- ance of the pigs. There was a tendency to higher growth rate for castrated males compared to gilts (807 vs. 776 g/day) (p<0.10). Consequently, castra- ted males finished the experiment 5.5 days earlier than gilts (p<0.05). The total feed consumption of gilts was significantly higher than that of castrated males (213.6 vs. 204.0 FU/pig) (p<0.05), and a tendency to better feed conversion in castrated males was noticed (p<0.10). Carcass quality The carcass trait results showed that the pigs on low lysine diets deposited more fat and less lean com- pared to the pigs on high lysine diets. The eye muscle area of the high lysine pigs was significant- ly larger than that of low lysine pigs (p<0.001). Significant differences were found also in the lean content of carcass (p<0.05) and in the loss at slaughter (in relation to live weight) (p<0.01) be- tween the low and high lysine diets. There was also a tendency to higher content oflean in valuable cuts for the pigs on high lysine diets compared to those on low lysine diets (p<0.10). However, no signific- ant differences were detected in side fat or back fat thickness between the high lysine and low lysine diets (p>0.!0). This was partly due to high coeffi- cients of variationfor both measurements (0.17 and 0.24 for side fat and back fat thickness, respective- ly)- There were no significant differences in thick- ness ofback fat and side fat, lean in valuable cuts or lean in whole carcass between the pigs fed on crys- talline or liquid lysine (p>0.10). Neither were any interactions found between lysine level and form ol supplementation in carcass trait measurements. 563 Agric. Sei. Finl. 1 (1992) However, the eye muscle area of the pigs given lysine in liquid form was significantly larger (p<0.05) than that ofpigs given lysine in crystalline form. There were significant differences between the sexes also in the area of eye muscle (p<0.05), por- tion of lean in valuable cuts (p<0.01) and in whole carcass (p<0.05) (Table 3.). In all these measure- ments the gilts were superior to castrated males. Discussion The main purpose of this work was to investigate whether supplementation of lysine in the form of liquid compared to crystalline has any effect on the performance and the carcass quality of the pigs. In order to establish the full effect of the different lysine sources, two levels of supplementation were used (0.9 and 3.2 g pure lysine per kg DM). The performance results clearly showed that the pigs responded similarly to both forms of lysine and they confirm the earlierresults of NÄSI (1992) who found no differences in nitrogen retention of the pigs fed on diets supplemented either with liquid or crystalline lysine. Gruhn et al. (1982) observed no differences in the protein utilization between microbially produc- ed lysine concentrateand crystalline lysine. In con- trats to this, Liebert and Gebhardt(1984) report- ed that microbially produced lysine might have better utilization than crystalline lysine due to a complexity of composition which causes longer absorption time from the small intestine. In the carcass quality measurements of the present study the liquid lysine yielded a significantly larger area ofeye muscle compared to crystalline lysine. How- ever, the other carcass measurements did not con- firm the hypothesis of better utilization of microbi- ally produced lysine. Free lysine is absorbed very rapidly from the small intestine and this causes reduced utilization when fed only once daily compared to frequent feeding (six times per day) (Batterham (1974). Partridge et al. (1985) also reported that the utili- zation of free lysine measured as N-balance in- creased from once to twice daily feeding, but no further response was found to increases in frequen- cy of feeding from twice daily. Thus, the twice daily feeding regime in the present study should have been sufficient for the effective utilization of free lysine. The recent reports of the comparisons of protein-bound lysine to crystalline lysine indicate that the utilization of crystalline lysine might be less than 100 % (Matre and Homb 1991, SuSEN- BETH et al. 1991). Fuller et al. (1986) found that addition of protein-bound lysine (soybean meal) to the diet induced a greater increase in daily live weight gain compared to lysine added in the free form, but the difference in terms of carcass gain was not apparent because of the differences in gut fill. There is variation in the digestibility or availa- bility of lysine in different feedstuffs (Batterham et al. 1978, Sauer and Ozimek 1986). In the work of Batterham et al. (1978) the comparison of eight protein concentrates on a total lysine basis in lysine-deficient diets for pigs showed that with fish meal, skim milk powder, rapeseed meal and soy- bean meal growth rates and feed conversion effi- ciencies were similar and superior to those produc- ed with cottonseed meal, meat meal and sunflower meal. Batterham et al. (1981) also found that the availability of lysine measured by a slope-ratio assay was the highest for rapeseed meal (0.87) and the lowest for sunflower meal (0.59), being inter- mediate for lupinseed meal (0.74). The low estima- tes for available lysine in sunflower meal presum- ably reflects processing damage (Batterham et al. 1981). The growth and carcass characteristics of grow- ing pigs responded linearly to increasing lysine intake until a maximum was attained at which the response levelled off (Taylor et al. 1979, Yen et al. 1986a. 1986b). In this study the response of pigs to lysine between two levels of supplementation was assumed to be linear because the inflection point for pigs with high genetic potential is at a higher content of lysine than used in this experi- 564 Agric. Sei. Finl. 1 (1992) ment (Hanrahan 1989, Madsen et al. 1991). The linear regression coefficients calculated for daily gain and feed conversion ratio as a function oflevel of lysine in the diet were in agreement with the results of Yen et al. (1986b). The regression coeffi- cient for daily gain in this experiment was close to the value for gilts (46.74) and the coefficient for feed conversion efficiency was close to the value for boars (-0.199) calculated by Yen et al. (1986b) from 50 to 90 kg live weight, and they show the high genetic potential of the pigs in the present experiment. The regression coefficients calculated from the early period of growth from 25 to 55 kg live weight (Yen et al. 1986a) were generally steep- er than the coefficients from the later period of growth (Yen et al. 1986b), indicating that the actual response to lysine is curvilinear over the whole period of growth. In the study ofBatterham et al. (1985) the pigs showed linear response to lysine from 20 to 50 kg and a curvilinearresponse from 50 to 85 kg live weight. The results from the comparisons between sexes were rather surprising. The castrated males tended to show higher performance than the gilts, but at the same time deposited more fat and less lean meat than the gilts. As lean meat deposition has a lower associated energy cost than fat deposition, a high rate of fat deposition would normally be accompa- nied by a reduction in growth performance as was indicatedby the lysine levels in the present experi- ment. Yen et al. (1986b) observed that boars show- ed better growth and feed utilization than gilts, but gilts were superior to castrated males. In contrast to this. Taylor et al. (1979) and Fuller et al. (1986) found no significant differences in growth rate or feed:gain ratio between gilts and castrated males. Campbell et al. (1988) reported that between 20 and 40 kg live weight no differences were found in growth performance between gilts and entire males, but at higher live weights entire males grew faster and more efficiently than gilts. However, the car- cass quality of the gilts has been better than that of castrated males in earlier experiments (Taylor et al. 1979, Fuller et al. 1986, Yen et al. 1986b), which is in agreement with this study. In conclusion, the liquid form of lysine is as effective as the crystalline form in improving the performance of growing pigs. It is very useful in practical wet feeding systems in combination with undehydrated distillers solids and it improves the quality of the protein in distillers solids. Acknowledgements. The author is grateful to the staff of the Swine Research Station of the Agricultural Research Centre of Finland for the technical assistance during the experiment. Associate prof. Matti Näsi and Head of the Swine Research Station Timo Alaviuhkola are acknowledged for valuable comments on the manuscript. Financial support was recieved from Alko Ltd. and from the Agricultural Research Foundation of August Johannes and Aino Tiura. References AOAC 1984. Official methods of analysis. 14th edition. Association of Official Analytical Chemist. Arlington, Virginia. Batterham, E.S. 1974.The effect of frequency of feeding on the utilization of free lysineby growing pigs. Br. J. Nutr. 31:237-242. , Murison, R.D. & Lewis, C.E. 1978. An evaluation of total lysine as a predictor of lysine status in protein concentrates for growing pigs. Br. J. Nutr. 40: 23-28. —, Murison,R.D. & Lowe,R.F. 1981. Availability of lysine in vegetable protein concentrates as determined by the sloperatio assay with growing pigs and rats and by chem- ical techniques. Br. J. Nutr.4s: 401-410. , Giles, L.R. & Dettmann, E.B. 1985. Amino acid and energy interactions in growing pigs. 1. Effects of food intake, sex and live weight on the responses of growing pigs to lysine concentration. Anim. Prod. 40: 331-343. —, Andersen, L.M., Baigent.D.R., Darnell,R.E. & Taver- ner, M.R. 1990.A comparison of the availability and ileal digestibility of lysine in cottonseed and soya-bean meals for grower-finisher pigs. Br. J. Nutr. 64: 663-677. Beker, M.E., Wiestur, U.E., Latsars, A.A., Mezhinya, G.R. & Paberzs, A.O. 1971. Verfahren zur Herstellung des Futterkonzentrates von L-Lysin. Institut Mikrobiologii imeni A. Kirhensteina Akademii Nauk Latvijskoi SSR. Pat. 93704. 565 Agric. Sei. Finl. 1 (1992) Campbell, R.G., Taverner, M.R. & Curic, D.M. 1988. The effects of sex and live weight on the growing pig’s res- ponse to dietary protein. Anim. Prod. 46: 123-130. Fuller. M.F., Livingstone,R.M, Baird. B.A. & Atkinson, T. 1979a. The optimal amino acid supplementation of bar- ley for growing pig. I. Response of nitrogen metabolism to progressivesupplementation. Br. J. Nutr. 41: 321-331. , Mennie. I, & Crofts. R.M.J. 1979b. The optimal amino acid supplementation of barley for growing pigs. 2. Opti- mal additions of lysine and threonine for growth. Br. J. Nutr. 41:333-340. , Wood, J., Brewer, A.C., Pennie, K. & MacWilliam, R. 1986. The responses of growing pigs to dietary lysine, as free lysine hydrochloride or in soya-bean meal, and the influence of food intake. Anim. Prod. 43: 477-484. Gruhn, K., Ludke, H., Schöne. A., Henning, A. & Chemni- tius.K.-H. 1982. Einfluss des L-lysinmonohydrochlorids bzw. eines Lysinfutterkonzentrates auf die Verdaulich- keit des Rohproteins und der basischen Aminosäuren, sowie Ergebnisse der N-Bilanz bei Mastschweinen und kolostomierten Hennen. Arch. Tierernährung 32: 477- 482. Hankahan. T.J. 1989. The response of growing pigs to lysi- ne. The Feed Compounder No 7: 32-39. Kantakoe-eläinten teurasarvostelu japaloittelu. 1979. Sika 9, 2: 34-35. Liebert, F. & Gebhardt, G. 1984. Untersuchungen zum N- Umsatz wachsender Schweine unter besonderer Beach- tung der Lysinwirksamkeit unterschiedlicher Lysinquel- len. Arch. Tierernähr. 34: 379-385. Madsen, A., Petersen, J., Mortensen, H.P., Bejerholm, C. & Barton, P. 1991. Protein til han- og sogrise. Stigende mängder sojaskrä. Statens Husdyrbrugsforsog. Medde- lelse 795. 6 p. Matre.T. & Homb.T. 1991. Synletic amino acids as supple- ments to a barley/oat/soyabean based ration for growing pigs. Proc. 6th Int. Symp. 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SAS User’s Guide: Statistics. 956 p. 5 th Ed. SAS Institute Inc, Cary, NC, USA. Sauer.W.C. & Ozimek.L. 1986. Digestibility of amino acids in swine: results and their practical applications. A re- view. 15: 367-388. Susenbeth. A., Schneider, R. & Menke. K.H. 1991. The effect of protein-bound lysine versus free lysine on pro- tein retention in growing pigs. Proc. 6th Int. Symp. Pro- tein Metabolism and Nutrition, Herning, Denmark, p. 18- 20. Taylor, A.J., Cole, D.J.A. & Lewis, D. 1979. Amino acid requirements of growing pigs. 1. Effects of reducing protein level in diets containing high levels of lysine. Anim. Prod, 29: 327-338. Valaja, J. 1992, Puhtaiden aminohappojen avulla ympäris- töystävällisempiä sianrehuja. Sika 22, 2: 25-26. Yen, H.T., Cole, D.J.A. & Lewis, D. 1986a. Amino acid requirements of growing pigs. 7. The response of pigs from 25 to 55 kg live weight to dietary ideal protein. Anim. Prod. 43: 141-154. , Cole, D.J.A. & Lewis, D. 1986b. Amino acid require- ments of growing pigs. 8. The response of pigs from 50 to 90 kg live weight to dietary ideal protein. Anim. Prod. 43: 155-165. Manuscript received October 1992 Jarmo Valaja Agricultural Research Centre of Finland Swine Research Station SF-05840 Hyvinkää,Finland Present adress: University of Helsinki Department of Animal Science P.O. Box 28 SF-00014 University of Helsinki. Finland 566 Agric. Sd. Fint. 1 (1992) SELOSTUS Nestemäinen tai kiteinen lysiini lihasikojen ohratärkkelysrankkiruokinnan täydentäjänä Jarmo Valaja Maatalouden tutkimuskeskus Kasvatuskokeessa selvitettiin kiteisen tai nestemäisen lysiini- lisäyksen vaikutusta ohra-tärkkelysrankkidieetillä ruokittujen lihasikojen tuotantotuloksiin sekä teuraslaatuun. Kokeessa oli 40 koe-eläintä, jotka jaettiin neljään kymmenen sian ryhmään ja kasvatettiin yksilöruokinnalla 25 kilon alkupainosta 95 kilon elopainoon. Neljä koerehua sisälsivät saman määrän nestemäistä tärkkelysrankkia ja ohraa ja niihin lisättiin joko nestemäistä tai kiteistä lysiiniä siten, että dieettien kokonais- lysiinimääräksi tuli 7,1 tai 9,1 g lysiiniä/ry. Lisätyn puhtaan lysiinin määrä oli 0,9 tai 3,2 g/kg kuiva-ainetta. Nestemäisen tai kiteisen lysiinilisäyksen välillä ei havaittu eroja sikojen tuotantotuloksissa tai teuraslaadussa. Ainoas- taan pitkän selkälihaksen poikkipinta-alassa oliero kiteistä tai nestemäistä lysiiniä saaneiden eläinten välillä. Dieetin korkea lysiinitaso (9,1 g/ry) paransi selvästi sikojen päiväkasvua, rehuhyötysuhdetta ja teuraslaatua verrattuna matalaan lysiini- tasoon (7,1 g/ry). keikkojen tuotantotulokset olivat hiukan paremmat kuin imisien, mutta imisien teuraslaatu oli kuiten- kin selvästi parempi kuin leikkojen. Koe osoitti, että nestemäinen ja kiteinen lysiini ovat yhtä käyttökelpoisia sikojen ruokinnassa. Nestemäinen lysiini so- veltuu hyvin liemiruokintaan täydentämään nestemäisiä vilja- peräisiä valkuaisrehuja. 567 Agric. Sei. Finl. 1 (1992)