JOURNAL OF THE SCIENTIFIC AGRICULTURAL SOCIETY OF FINLAND 52 Maataloustieteellinen Aikakauskirja Vol. 11:12-16, 1981 Nutritive value for growing pigs of pekilo protein and torula yeast grown in spent sulphite liquour MAIJA-LIISA SALO and EEVA PEKKARINEN Department of Animal Husbandry, University of Helsinki, 00710 Helsinki 71 Abstract. The digestibility and nutritive value of pekilo protein (Paecilomyces varioti), and torula yeast (Can- dida utilis) were determined for four pigs weighing 35 —5O kg. The proportion of pekilo or torula was 30 %of the barley-based diet. The crude fat was determined by the standard ether extraction method and by the HCl- ether method. The first method indicated a low fat content and a highly negative digestibility of fat, but the se- cond showed that thepig is able to digest and absorb a large part of the ether-insoluble fat. The energy value the- reby increased 14 % for pekilo and 12 % for torula over those obtained by the conventional ether method. The same energy value was obtained for barley by both methods. The energy values (HCI-ether method) obtained for pekilo and torula were 0.96 and 0.95 F.U./kg DM (F. U. = 0.7 kg starch), or 13.41 and 12.98 MJ ME/kg DM, respectively. The protein values, corrected for nu- cleic acid nitrogen, were 434 and 3 58 g DCP/kg DM. The only significant difference between pekilo and toru- la was the DCP value (P< 0.001). The nitrogen balances in the pekilo and torula trials were very high and identical (24.4 and 24.0 g N/d), confirming the value of these feeds as protein supplements to cereal feeds for pigs. Introduction Two kinds of single-cell protein (SCP), the mycelium forming microfungi pekilo {Paecilomyces varioti) and torula yeast (Candida utilis), are cultivated in the sulphite spent liquor of the pulping industry in Finland. Pekilo and torula are much alike in composition (Table 1), but pekilo is rougher in texture. Now that production had been going on for several years, the process techniques and with them the quality of products have been stabilized. The value of pekilo and torula in animal feeding is similar. Both have been suc- cessfully used as the sole protein supplement for growing pigs (BARBER et al. 1971, 1978, ALAVIUHKOLA et al. 1975, 1978, HANSSEN 1978), from the freshly weaned stage onwards (BOBROV et al. 1978). In the feeding of broilers and calves, however, some restrictions have had to be introduced (BECK and GROPP 1974, KIISKINEN 1978, KOSSILA and KIISKINEN 1978). The amino acid composition and the protein value of pekilo and yeasts are well known, their energy values much less clear. Accordingly, the purpose of the present study was to determine the energy values of the domestic-produced pekilo protein and torula yeast for growing pigs. The digestible crude protein (DCP) values and the nitrogen balances were determined simultaneously. https://www.c-info.fi/en/info/?token=4MZGi1u4EEGL6oPP.JN1d4s0s1Ibq5W41m_8O1Q.MGcmeRpiiQmMFypDNqqHZgJQJNXmpzTmiCLQ2RaPgc1PLB7v2pNmxnLeIbuwWUWh8ucEuQedAXnwrsoM4bTBDrpNmqDFona_TzYT_KPDHI_i3voZKsdwVOUcOKe_leCvmd8e1VOEc6QGLnXEAf8CG8sZE41UGuI0Bnnn6ln5cQhP4XoNycZOiN5F1f1PDGLtyAw 53 Table 1. Chemical composition and digestibility coefficients for pigs of pekilo protein, torula yeast and barley. Org. Crude Crude Crude fat 1 NFE' matter protein fibre 12 12 Ash Pekilo: %inDM 92.958.3 8.41.4 4.424.8 21.87.1 digest.% 77.182.7 69.5 -166.653.1 74.564.0 50.2 Torula: %inDM 92.949.2 6.22.2 6.635.3 30.97.1 digest.% 73.180.9 54.8 -69.767.0 70.460.0 56.4 Barley: %inDM 97.111.4 5.92.4 3.577.4 76.32.9 digest.% 86.3 86.2 28.282.9 56.690.8 92.165.9 ' Crude fat = ether extract ' Crude fat = 4 N HCI + ether extract Materials and methods Pekilo and torula were products of the normal industrial production. Their com- positions, and the composition of the barley used as basic feed in the trials, are shown in Table 1. The digestibility trials were carried out with four castrated pigs weighing 35 50 kg. The proportion of pekilo or torula was 30 % of the barley-based diet. In the basic digestibility trial with barley, 16 %of skim milk powder was incorporated for protein supplement. The preliminary period was 10 days and the collection period 7 days. The details of the digestibility trials have been described in an earlier paper (SALO and ALAVIUHKOLA 1980). Results and discussion The crude fat was determined both as normal ether extract and as HCI-fat (boi- ling in 4 N HCI before extraction with ether). Digestibility coefficients and energy values were calculated on the basis of both fat determinations (Tables 1 and 2). The digestibility coefficients found lie within the wide range presented in the li- terature, though at the lower end of the range (ANON. 1970, BREIREM and HOME 1970, NEHRING et al. 1970, SCHULZ and OSLAGE 1976, ANON. 1979). The nutritive data for pekilo and torula agree very well with each other, better than the Table 2. Energy values when crude fat is determined as ether extract (1), and as HCI-ether extract (2), and DCP values. Pekilo Torula Barley I 2 1 2 1 2 FU./kg DM 1 0.83 0.96 0.84 0.95 1.16 1.16 M] ME/kg DM 12.54 13.41 11.90 12.98 14.91 14.95 DCP.g/kgDM 4342 358 2 98 F.U. =0.7 kg starch 2 Corrected values, see text. data in many experiments for two different batches of yeast. Perhaps the cultivation medium has a greater effect on the nutritive quality of SCP than does the strain of microbe. And perhaps the SCP from sulphite liquor has a little lower digestibility than the SCP from some other energy sources, as some literature data suggest (NEHRING et al. 1970, ANON. 1970). In addition to protein the microbe products contain about 35% carbohydrates and 4 10 % fat. The composition of both these groups differs greatly from that of conventional feeds. The carbohydrates resemble the hemicellulose of higher plants in solubility, but their composition is quite different. The principal units arc glucose and mannose, whereas xylose and arabinose, the essential polysaccharide components of higher plants, are wholly lacking. Hexoseamines are also typical of the microbe products. Sugar and starch, on the other hand, occur only in traces and solubilities in the amy- loglucosidase and pepsin incubations are small (SCHULZ and OSLAGE 1976, SALO 1977). The digestion of yeast cell wall polysaccharides by the digestive enzymes of the calfs small intestine is very small (GAILLARD and WEERDEN 1976). Consequently, yeast and pekilo have proved to be a somewhat problematic feed for calves (SCHULZ and OSLAGE 1976, KOSSILA and KIISKINEN 1978). The division of the cell wall compounds into crude fibre and nitrogen free extracts is artificial and serves no purpose here, as can be seen from the digestion coefficients, which are al- most identical for the two groups. Moreover, the crude fibre sontent of SCP de- pends essentially on the filtration technique (SALO 1977). The pigs proved to digest the carbohydrates of pekilo and torula rather well with the assistance of the bacterial flora of their large intestine. Not so well, how- ever, that the energy values approached those of the common cereal grains. The crude fat is another group that differs from that of conventional feeds. The fat content is variable and can rise several-fold, when the SCP is hydrolysed with 4 N HCI before extraction with ether (SCHILLER et al. 1972, SALO 1977, HANSSEN 1978). The digestibility coefficients found here suggest that the alimentary canal of pig hydrolyses more fat into an ether soluble form than can be absorbed into the blood circulation, resulting in a highly negative digestion coefficient (Table 1). On the ot- her hand, the pig does digest a good part of the ether insoluble fat, with the result that the energy values calculated by the HCI-fat method are 12—14 % higher (Table 2) and in all probability truer than the values arrived at by the conventional et- her method. In respect to barley there is no difference in energy value between these two fat determination methods: the HCI -method shows a higher fat content, and lower digestibility correspondingly. The digestible crude protein values of Table 2 are corrected for nucleic acid nit- rogen. It is well known that 10—20 % of the nitrogen of yeasts is included in the nu- Table 3. Nitrogen balances of various digestibility trials. Diet DCP, g/F.U. N-balance gN/d Barley Skim milk powder 122 18.2 Barley Pekilo 190 24.4 Barley Torula 167 24.0 54 55 cleic acids (SCHULZ and OSLAGE 1976, ROTH and KIRCHGESSNER 1980), and the same is true for the pekilo (SALO 1978). Further, it is known that the pig digests about 9 5 % of the nucleic acid nitrogen, but less than one third of it is retained in the body, the rest being excreted in the urine (ROTH and KIRCHGESSNER 1977, 1980). The DCP values of Table 2 are roughly corrected on the basis of this know- ledge (15 % content and 30 % utilization). The palatability of pekilo and tornia was good at the 30 % level of the diet. The retention of nitrogen was very high, considering that the normal restricted feeding was used (Table 3). The results only strengthen the many earlier findings that pekilo and yeast are very promising protein supplements to cereal feeds for pigs. References ALAVIUHKOLA, T., KORHONEN, 1., PARTANEN, J. & LAMPILA, M. 1975. Pekilo protein in the nutrition of growing-finishing pigs. Acta Agric. Scand. 25: 301 305. ALAVIUHKOLA, T. 1978. Experiences on feeding pigs with Pckilo. Agric. Res. Centre, Finl. Inst. Anim. Husb. Rep. 12: 33-45. ANON. 1970. DLG-Futterwerttabelle fiir Schwcinc. 32 p. Frankfurt am Main. ANON. 1979. Veevocdcrtabel. 89 p. Nederland. BARBER. R. S., BRAUDE, R., MITCHELL, K. G. & MYRES, A. W. 1971. The value of hydrocarbon- grown yeast as a source of protein for growing pigs. Br. J. Nutr. 25: 285—294. BARBER, R. S., BRAUDE, R. & MITCHELL, K. G. 1977. The value of "Pekilo protein” for growing pigs. Anim. Feed Sci. Tcchnol. 2: 161 169. BECK, H. & GROPP, ]. 1974. Alkanhefen in der Geflugelernährung. 2. Bishcrigc Erfahrungen mit Alkanhc- fen in der Tierernährung. Z. Tierphys., Tierernahr., Futtcrmittclk. 33: 305 323. BOBROV, E. P., CHIKOV, A. E. & ZHERNOVOJ, I. T. 1978. Efficiency of using Pekilo-protcin in fee- ding of early weaned pigs. Agric. Res. Centre, Finl. Inst. Anim. Husb. Rep. 12: 50—53. BREIREM, K. & HOMB, T. 1970. Förmidlcr og förkonservering. 459 p. Gjovik. GAILLARD, B. D. E. & WEERDEN, E. J. van. 1976. The digestion of yeast cell wall polysaccharides in veal calves. Br. J. Nutr. 36: 471—478. HANSSEN, J. T. 1978. Nutritional experiences of feeding pigs with the Pckilo. Agric. Res. Centre, Finl., Inst. Anim. Husb., Rep. 12: 54—64. KIISKINEN, T. 1978. Pekilo in the feeding of poultry. The results of the experiments carried out in Finland. Agric. Res. Centre, Finl., Inst. Anim. Husb., Rep. 12: 133—143. KOSSILA, V. & KIISKINEN, T. 1978. Pekilo-protcin in the calf starters. Agr. Res. Centre, Finl., Inst. Anim. Husb. Rep. 12: 150—161. NEHRING, K., BEYER, M. & HOFFMANN, B. 1970. Futtermitteltabcllenwerk. 460 p. Berlin. ROTH, F. X. & KIRCHGESSNER, M. 1977. N-Ausnutzung und N-Bewertung steigender Gaben von Bakterien- und Sojaprotein bei wachsenden Schweinen. Z. Tierphys., Ticrern. Futtcrmittclk. 39: 156 170. ROTH, F. X. & KIRCHGESSNER, M. 1980. Alimentär zugefiihrte Nukleinsäuren im N-Stoffwechscl von Monogastriden. Arch. Tierernahr. 30: 77—88. SALO, M.-L. 1977. The carbohydrate composition and solubility of Pekilo protein and two yeasts. Acta Agric. Scand. 27: 77-80. SALO, M.-L. 1978. Chemical composition and feed value of the Pckilo. Agric. Res. Centre, Finl., Inst. Anim. Husb., Rep. 12: 9-20. SALO, M.-L. & ALAVIUHKOLA, T. 1980. Normal and light weight oats as feed for growing pigs. J. Scient. Agric. Soc. Finl. 52: 435—440. SCHILLER, K., SIMECEK, K. & OSLAGE, H. J. 1972. Mikrobiell produzicrtc Eiwcissfuttcrmittcl in der Tierernährung. 1. Untersuchungcn zur crnährungsphysiologischcn Bcwcrtung des Proteins von Hefen, gewachsen auf Rohöl-, n-Paraffmen und anderen Substraten. Z. Tierphys., Ticrern., Futtcrmittclk. 30; 246-259. 56 SCHULZ, E. & OSLAGE, H. J. 1976. Composition and nutritive value of single-cell protein (SCP). Anim. Feed Sci. Technol. 1: 9—24. Ms received January 22, 1981 SELOSTUS Sulfiittijäteliemcssä viljeltyjen kotimaisten tnikrobituotteiden rehuarvo lihasialla Maija-Liisa Salo ja Eeva Pekkarinen Helsingin yliopiston kotieläintieteen laitos, 00710 Helsinki 71 Pekilon ja silvan (torula-hiiva) rchuarvo määritettiin neljällä 35—50 kg painoisella lihasialla sulavuusko- kcessa, missä perusrchuna oli ohra ja pekiloa tai silvaa oli 30 % dieetistä. Raakarasva määritettiin sekä virallisen rehuanalyysin eetterimenetelmällä että 4 N HCI-keiton jälkeen eetterillä. Edellisellä saatiin matala rasvapitoisuus ja vahvasti negatiivinen sulavuuskerroin. Jälkimmäinen osoitti, että sika pystyy sulattamaan niin paljon eetteriin liukenematonta rasvaa, että HCI-ectterimcnetelmällä tulee pekilolle 14 % ja Silvalle 12 %parempi ja nähtäväs- ti oikeampi ry-arvo. Ohralle sen sijaan saatiin sama energia-arvo kummallakin rasvamäärityksellä. Menetel- män tarkistus lienee siten tarpeen vain joillakin erikoisilla rehuilla, kuten juuri mikrobituotteilla. Todetut energia-arvot olivat pekilolle ja Silvalle 0.96 ja 0.95 ry/kg ka tai muuntokelpoisena energiana 1 3.41 ja 12.98 MJ ME/kg ka. Srv-arvoihin tehtiin nukleiinihappokorjaus, mikä alensi arvoja noin 10 %. Korja- tut arvot olivat pekilolle 434 ja Silvalle 358 g srv/kg ka. Valkuaisarvo oli ainoa, missä nämä kaksi rehua merkit- sevästi poikkesivat toisistaan (P<0.001). Typpitaseet olivat pekilo- ja silvakokeissa korkeat (24.4 ja 24.0 g N/d) vahvistaen aikaisempia tuloksia, että nämä mikrobituotteet sopivat hyvin lihasian ainoaksikin valkuaisrchuksi.