Hostname: page-component-cd9895bd7-hc48f Total loading time: 0 Render date: 2024-12-25T17:37:41.832Z Has data issue: false hasContentIssue false

Organic acids for performance enhancement in pig diets

Published online by Cambridge University Press:  24 October 2008

Krisi H Partanen*
Affiliation:
Institute for Animal Science and Health (ID-DLO), Department of Nutrition of Pigs and Poultry, PO Box 65, 8200 AB Lelystad, The Netherlands
Zdzislaw Mroz
Affiliation:
Institute for Animal Science and Health (ID-DLO), Department of Nutrition of Pigs and Poultry, PO Box 65, 8200 AB Lelystad, The Netherlands
*
*Corresponding author: current address Agricultural Research Centre of Finland, Animal Production Research, 31600 Jokionen, Finland, fax +358 3 418 83661, email kirsi.partanen@mtt.fi
Rights & Permissions [Opens in a new window]

Abstract

Core share and HTML view are not available for this content. However, as you have access to this content, a full PDF is available via the ‘Save PDF’ action button.

Organic acids and their salts appear to be potential alternatives to prophylactic in-feed antibiotics and growth promoters in order to improve the performance of weaned piglets, fattening pigs and reproductive sows, although their growth-promoting effects are generally less than that of antibiotics. Based on an analysis of published data, the growth-promoting effect of formates, fumarates and citrates did not differ in weaned piglets. In fattening pigs, formates were the most effective followed by fumarates, whereas propionates did not improve growth performance. These acids improved the feedgain ratio of both weaned piglets and fattening pigs. In weaned piglets, the growth-promoting effects of dietary organic acids appear to depend greatly on their influence on feed intake. In sows, organic acids may have anti-agalactia properties. Successful application of organic acids in the diets for pigs requires an understanding of their modes of action. It is generally considered that dietary organic acids or their salts lower gastric pH, resulting in increased activity of proteolytic enzymes and gastric retention time, and thus improved protein digestion. Reduced gastric pH and increased retention time have been difficult to demonstrate, whereas improved apparent ileal digestibilities of protein and amino acids have been observed with growing pigs, but not in weaned piglets. Organic acids may influence mucosal morphology, as well as stimulate pancreatic secretions, and they also serve as substrates in intermediary metabolism. These may further contribute to improved digestion, absorption and retention of many dietary nutrients. Organic acid supplementation reduces dietary buffering capacity, which is expected to slow down the proliferation and|or colonization of undesirable microbes, e.g. Escherichia coli, in the gastro-ileal region. However, reduced scouring has been observed in only a few studies. As performance responses to dietary organic acids in pigs often varies, more specific studies are necessary to elucidate an explanation.

Type
Research Article
Copyright
Copyright © CABI Publishing 1999

References

Abu Damir, H, Scott, D, Loveridge, N, Buchan, W & Milne, J (1991) The effects of feeding diets containing either NaHCO3 or NH4Cl on indices of bone formation and resorption and on mineral balance in the lamb. Experimental Physiology 76, 725732.CrossRefGoogle ScholarPubMed
Argenzio, A (1984) Gastrointestinal motility. In Duke's Physiology of Domestic Animals, pp. 278289 [Swenson, MJ, editor]. Ithaca, NY: Cornell University Press.Google Scholar
Aumaître, A, Peiniau, J & Madec, F (1995) Digestive adaptation after weaning and nutritional consequences in the piglet. Pig News and Information 16, 73N79N.Google Scholar
Barzel, US & Jowsey, J (1969) The effects of chronic acid and alkali administration on bone turnover in adult rats. Clinical Science 36, 517524.Google Scholar
Baustad, B (1993) Effects of formic acid on performance in growing pigs. Norwegian Journal of Agricultural Sciences 7, 6169.Google Scholar
Bolduan, G, Jung, H, Schneider, R, Block, J & Klenke, B (1988 a) Influence of propionic and formic acids on piglets. Journal of Animal Physiology and Animal Nutrition 59, 7278.CrossRefGoogle Scholar
Bolduan, G, Jung, H, Schneider, R, Block, J & Klenke, B (1988 b) Influence of fumaric acid and propanediol formate on piglets. Journal of Animal Physiology and Animal Nutrition 59, 143149.CrossRefGoogle Scholar
Broz, J & Schulze, J (1987) Efficacy of citric acid as a feed additive in early weaned piglets. Journal of Animal Physiology and Animal Nutrition 58, 215223.CrossRefGoogle Scholar
Burnell, TW, Cromwell, GL & Stahly, TS (1988) Effects of dried whey and copper sulfate on the growth responses to organic acid in diets for weanling pigs. Journal of Animal Science 66, 11001108.CrossRefGoogle ScholarPubMed
Cera, KR, Mahan, DC, Cross, RF, Reinhart, GA & Whitmoyer, RE (1988) Effect of age, weaning and postweaning diet on small intestinal growth and jejunal morphology in young swine. Journal of Animal Science 66, 574584.CrossRefGoogle ScholarPubMed
Chang, EB & Rao, MC (1994) Intestinal water and electrolyte transport. Mechanisms of physiological and adaptive responses. In Physiology of the Gastrointestinal Tract, 3rd ed., pp. 20272075 [Johnson, LR, Alpers, DH, Christensen, J and Jacobsen, E, editors]. New York: Lippencott Raven Press.Google Scholar
Clark, WA & Batterham, ES (1989) Citric acid supplementation of creep-weaner diets. In Manipulating Pig Production II, p. 137 [Barnett, JL and Hennesy, DP, editors]. Werribee, Victoria, Australia: Australasian Pig Science Association.Google Scholar
Cole, DJ A, Beal, RM & Luscombe, JR (1968) The effect on performance and bacterial flora of lactic acid, propionic acid, calcium propionate and calcium acrylate in the drinking water of weaned pigs. Veterinary Record 83, 459463.CrossRefGoogle ScholarPubMed
Cranwell, PD (1995) Development of the neonatal gut and enzyme systems. In The Neonatal Pig: Development and Survival, pp. 99154 [Varley, MA, editor]. Wallingford, Oxon.: CAB International.Google Scholar
Easter, RA (1988) Acidification of diets for pigs. In Recent Advances in Animal Nutrition — 1988, pp. 6171 [Haresign, W and Cole, DJA, editors]. London: Butterworths.CrossRefGoogle Scholar
Eckel, B, Kirchgessner, M & Roth, FX (1992 a) Influence of formic acid on daily weight gain, feed intake, feed conversion rate and digestibility. 1. The nutritive value of organic acids in the rearing of piglets. Journal of Animal Physiology and Animal Nutrition 67, 93100.CrossRefGoogle Scholar
Eckel, B, Roth, FX, Kirchgessner, M & Eidelsburger, U (1992 b) Influence of formic acid on concentrations of ammonia and biogenic amines in the gastrointestinal tract. 4. Nutritive value of organic acids in piglet rearing. Journal of Animal Physiology and Animal Nutrition 67, 198205.CrossRefGoogle Scholar
Edmonds, MS, Izquierdo, OA & Baker, DH (1985) Feed additive studies with newly weaned pigs: efficacy of supplemental copper, antibiotics and organic acids. Journal of Animal Science 60, 462469.CrossRefGoogle ScholarPubMed
Eidelsburger, U, Kirchgessner, M & Roth, FX (1992 a) Influence of formic acid, calcium formate and sodium bicarbonate on pH, concentration of carbonic acids and ammonia in different segments of the gastrointestinal tract. 8. Nutritive value of organic acids in piglet rearing. Journal of Animal Physiology and Animal Nutrition 68, 2032.CrossRefGoogle Scholar
Eidelsburger, U, Kirchgessner, M & Roth, FX (1992 b) Influence of fumaric acid, hydrochloric acid, sodium formate, tylosin and toyocerin on daily weight gain, feed conversion rate and digestibility. 11. Nutritive value of organic acids in piglet rearing. Journal of Animal Physiology and Animal Nutrition 68, 8292.CrossRefGoogle Scholar
Eidelsburger, U, Kirchgessner, M & Roth, FX (1992 c) Influence of fumaric acid, hydrochloric acid, sodium formate, tylosin and toyocerin on acid-base status. 13. Nutritive value of organic acids in piglet rearing. Journal of Animal Physiology and Animal Nutrition 68, 165173.CrossRefGoogle Scholar
Eidelsburger, U, Roth, FX & Kirchgessner, M (1992 d) Influence of formic acid, calcium formate and sodium bicarbonate on daily weight gain, feed intake, feed conversion rate and digestibility. 7. Nutritive value of organic acids in piglet rearing. Journal of Animal Physiology and Animal Nutrition 67, 258267.CrossRefGoogle Scholar
Eidelsburger, U, Roth, FX & Kirchgessner, M (1992 e) Influence of formic acid, calcium formate and sodium bicarbonate on acid-base status. 9. Effect of organic acids in piglet rearing. Journal of Animal Physiology and Animal Nutrition 68, 3342.CrossRefGoogle Scholar
Falkowski, JF & Aherne, FX (1984) Fumaric and citric acid as feed additives in starter pig nutrition. Journal of Animal Science 58, 935938.CrossRefGoogle Scholar
Fasshauer, U & Kienzle, E (1995) Effect of citric acid, olaquindox, zinc-bacitracin and zinc oxide on precaecal digestion of crude nutrients and ileocaecal flow of minerals in minipigs. Journal of Animal Physiology and Animal Nutrition 74, 219226.CrossRefGoogle Scholar
Foegeding, PM & Busta, FF (1991) Chemical food preservatives. In Disinfection, Sterilization and Preservation, pp. 802832 [Block, SS, editor]. Philadelphia, PA: Lea & Febiger.Google Scholar
Frank, K (1994) Measures to preserve food and feeds from bacterial damage. Übersichten zur Tierernährung 22, 149163.Google Scholar
Frankel, WL, Zhang, W, Singh, A, Klurfeld, DM, Don, S, Sakata, T, Modlin, I & Rombeau, JL (1994) Mediation of the trophic effects of short-chain fatty acids on the rat jejunum and colon. Gastroenterology 106, 375380.CrossRefGoogle ScholarPubMed
Fuller, R (1977) The importance of lactobacilli in maintaining normal microbial balance in the crop. British Poultry Science 18, 8994.CrossRefGoogle ScholarPubMed
Gabert, VM & Sauer, WC (1994) The effects of supplementing diets for weanling pigs with organic acids. A review. Journal of Animal and Feed Sciences 3, 7387.CrossRefGoogle Scholar
Gabert, VM & Sauer, WC (1995) The effect of fumaric acid and sodium fumarate supplementation to diets for weanling pigs on amino acid digestibility and volatile fatty acid concentrations in ileal digesta. Animal Feed Science and Technology 53, 243254.CrossRefGoogle Scholar
Gabert, VM, Sauer, WC, Schmitz, M, Ahrens, F & Mosenthin, R (1995) The effect of formic acid and buffering capacity on the ileal digestibilities of amino acids and bacterial populations and metabolites in the small intestine of weanling pigs fed semipurified fish meal diets. Canadian Journal of Animal Science 75, 615623.CrossRefGoogle Scholar
Gálfi, P & Bokori, J (1990) Feeding trial in pigs with a diet containing sodium n-butyrate. Acta Veterinaria Hungarica 38, 317.Google ScholarPubMed
Gaskins, HR & Kelley, KW (1995) Immunology and neonatal mortality. In The Neonatal Pig: Development and Survival, pp. 3955 [Varley, MA, editor]. Wallingford, Oxon.: CAB InternationalGoogle Scholar
Gedek, B, Kirchgessner, M, Eidelsburger, U, Wiehler, S, Bott, A & Roth, FX (1992 a) Influence of formic acid on the microflora in different segments of the gastrointestinal tract. 5. Nutritive value of organic acids in piglet rearing. Journal of Animal Physiology and Animal Nutrition 67, 206214.CrossRefGoogle Scholar
Gedek, B, Roth, FX, Kirchgessner, M, Wiehler, S, Bott, A & Eidelsburger, U (1992 b) Influence of fumaric acid, hydrochloric acid, sodium formate, tylosin and toyocerin on the microflora in different segments of the gastrointestinal tract. 14. Nutritive value of organic acids in piglet rearing. Journal of Animal Physiology and Animal Nutrition 68, 209217.CrossRefGoogle Scholar
Giesting, DW & Easter, RA (1985) Response of starter pigs to supplementation of corn-soybean meal diets with organic acids. Journal of Animal Science 60, 12881294.CrossRefGoogle ScholarPubMed
Giesting, DW & Easter, RA (1991) Effect of protein source and fumaric acid supplementation on apparent ileal digestibility of nutrients by young pigs. Journal of Animal Science 69, 24972503.CrossRefGoogle ScholarPubMed
Giesting, DW, Roos, MA & Easter, RA (1991) Evaluation of the effect of fumaric acid and sodium bicarbonate addition on performance of starter pigs fed diets of different types. Journal of Animal Science 69, 24892496.CrossRefGoogle ScholarPubMed
Grassmann, E & Kirchgessner, M (1979) Absorption of copper from complexes with various organic acids. Zeitschrift für Tierphysiologie, Tierernährung und Futtermittelkunde 25, 125128.CrossRefGoogle Scholar
Grassmann, E & Klasna, T (1986) Comparative studies on the effect of supplements of fumaric and citric acids on body composition and enzyme activities of rats differently supplied with protein. Landwirtschaftliche Forschung 39, 307319.Google Scholar
Grassmann, E, Roth, FX & Kirchgessner, M (1992) Metabolic effects of formic acid in daily use. 6. Nutritive value of organic acids in piglet rearing. Journal of Animal Physiology and Animal Nutrition 67, 250257.CrossRefGoogle Scholar
Harada, E & Kato, S (1983) Effect of short-chain fatty acids on the secretory response of the ovine exocrine pancreas. American Journal of Physiology 244, G284G290.Google ScholarPubMed
Harada, E, Kiriyama, H, Kobayashi, E & Tsuchita, H (1988) Postnatal development of biliary and pancreatic exocrine secretion in piglets. Comparative Biochemistry and Physiology 91A, 4351.Google Scholar
Harada, E, Niiyama, M & Syuto, B (1986) Comparison of pancreatic exocrine secretion via endogenous secretin by intestinal infusion of hydrochloric acid and monocarboxylic acid in anesthetized piglets. Japanese Journal of Physiology 36, 843856.Google ScholarPubMed
Hedges, LV & Olkin, I (1985) Statistical Methods for Meta-Analysis. San Diego, CA: Academic Press.Google Scholar
Henry, RW, Pickard, DW & Hughes, PE (1985) Citric acid and fumaric acid as food additives for early-weaned piglets. Animal Production 40, 505509.Google Scholar
Höhler, D & Pallauf, J (1993) Effect of citric acid added to a maize-soya diet with or without Zn supplementation on the availability of minerals. Journal of Animal Physiology and Animal Nutrition 69, 133142.CrossRefGoogle Scholar
Höhler, D & Pallauf, J (1994) Effect of Zn supply and addition of citric acid to a maize-soya diet on the nutritive value and mineral absorption in piglets. Journal of Animal Physiology and Animal Nutrition 71, 189199.CrossRefGoogle Scholar
Imoto, S & Namioka, S (1983) Nutritive value of acetate in growing pigs. Journal of Animal Science 56, 858866.CrossRefGoogle ScholarPubMed
Jahn, S & Uecker, E (1987) Research on the economics of enterotoxaemia due to coliforms in pigs. Monatshefte für Veterinär Medizin 42, 769771.Google Scholar
Jasaitis, DK, Wohlt, JE & Evans, JL (1987) Influence of feed ion content on buffering capacity of ruminant feedstuffs in vitro. Journal of Dairy Science 70, 13911403.CrossRefGoogle Scholar
Johlin, FC, Fortman, CS, Nghiem, DD & Tephly, TR (1987) Studies on the role of folic acid and folate-dependent enzymes in human methanol poisoning. Molecular Pharmacology 31, 557561.Google ScholarPubMed
Johlin, FC, Swain, E, Smith, C & Tephly, TR (1989) Studies on mechanism of methanol poisoning: purification and comparison of rat and human liver 10-formyltetrahydrofolate dehydrogenase. Molecular Pharmacology 35, 745750.Google ScholarPubMed
Jongbloed, AW (1987) Phosphorus in the Feeding of Pigs. Effect of the Diet on the Absorption and Retention of Phosphorus by Growing Pigs. Report no. 179. Lelystad, The Netherlands: IVVO.Google Scholar
Jongbloed, AW & Jongbloed, R (1996) The Effect of Organic Acids in Diets for Growing Pigs on Enhancement of Microbial Phytase Efficacy. ID-DLO Report no. 96009. Lelystad, The Netherlands: Insitute for Animal Science and Health.Google Scholar
Jongbloed, AW, Kemme, PA, Mroz, Z & Mäkinen, M (1995) Apparent total tract digestibility of ash and minerals in pigs as affected by phytate, microbial phytase, and lactic acid. Journal of Animal Science 73,(Suppl. 1), 188.Google Scholar
Kato, S, Asakawa, N, Mineo, H & Ushijima, J (1989) Effect of short-chain fatty acids on pancreatic exocrine secretion in calves aged 2 weeks and 13 weeks. Japanese Journal of Veterinary Science 51, 11231127.Google Scholar
Kemme, PA, Jongbloed, AW, Mroz, Z & Mäkinen, M (1995) Apparent ileal amino acid digestibility in pigs as affected by phytate, microbial phytase, and lactic acid. Journal of Animal Science 73, Suppl. 1, 173.Google Scholar
Kidder, DE & Manners, MJ (1978) Digestion in the Pig. Bristol, Avon: Scientechnica.Google Scholar
Kirchgessner, M, Eckel, B, Roth, FX & Eidelsburger, U (1992) Influence of formic acid on carcass composition and retention of nutrients. 2. Nutritive value of organic acids in piglet rearing. Journal of Animal Physiology and Animal Nutrition 67, 101110.CrossRefGoogle Scholar
Kirchgessner, M, Paulicks, BR & Roth, FX (1997) Effects of supplementations of diformate complexes (FormiTM LHS) on growth and carcass performance of piglets and fattening pigs in response to application time. Agribiological Research 50, 17.Google Scholar
Kirchgessner, M & Roth, FX (1976) Rearing piglets on a diet containing fumaric acid. Züchtungskunde 48, 402406.Google Scholar
Kirchgessner, M & Roth, FX (1978 a) Fumaric acid as a supplement in rearing piglets and in fattening pigs. Züchtungskunde 50, 1725.Google Scholar
Kirchgessner, M & Roth, FX (1978 b) Effect of the addition of fumaric acid on the nutritive value and energy intake. Zeitschrift für Tierphysiologie, Tierernährung und Futtermittelkunde 42, 7176.CrossRefGoogle Scholar
Kirchgessner, M & Roth, FX (1980) Digestibility and balance of protein, energy and some minerals in piglets given supplements of fumaric acid. Zeitschrift für Tierphysiologie, Tierernährung und Futtermittelkunde 44, 239246.CrossRefGoogle Scholar
Kirchgessner, M & Roth, FX (1982) Propionic acid as a feed additive in the rearing of piglets and fattening of pigs. Wirtschaftseigene Futter 28, 225234.Google Scholar
Kirchgessner, M & Roth, FX (1987 a) Use of formates in the feeding of piglets. 1. Calcium formate. Landwirtschaftliche Forschung 40, 141152.Google Scholar
Kirchgessner, M & Roth, FX (1987 b) Use of formates in piglet nutrition. 2. Sodium formate. Landwirtschaftliche Forschung 40, 287294.Google Scholar
Kirchgessner, M & Roth, FX (1988) Energy value of organic acids in the rearing of piglets and the fattening of pigs. Übersichten zur Tierernährung 16, 93108.Google Scholar
Kirchgessner, M & Roth, FX (1989) Use of calcium formate in the fattening of pigs. Landwirtschaftliche Forschung 42, 150156.Google Scholar
Kirchgessner, M & Roth, FX (1990) Nutritive effect of calcium formate in combination with free acids in the feeding of piglets. Agribiological Research 43, 5364.Google Scholar
Kirchgessner, M, Roth, FX & Eidelsburger, U (1993) Nutritive value of tartaric and malic acids in piglet rearing. Journal of Animal Physiology and Animal Nutrition 70, 216224.CrossRefGoogle Scholar
Kirchgessner, M, Roth, FX & Paulicks, BR (1995) Nutritive value of sorbic acid in piglet rearing. Journal of Animal Physiology and Animal Nutrition 74, 235242.CrossRefGoogle Scholar
Kirchgessner, M & Roth-Maier, DA (1975) The addition of citric acid to piglet rations. Züchtungskunde 47, 329335.Google Scholar
Kokue, E, Sekiya, T, Shinoda, M & Natsuhori, M (1994) Pharmacokinetics and bioavailability of folic acid and plasma levels of bioactive folates after folic acid administration to pigs. Veterinary Quarterly 16, 9194.CrossRefGoogle ScholarPubMed
Kornegay, ET, Evans, JL & Ravindran, V (1994) Effects of diet acidity and protein level or source of calcium on the performance, gastrointestinal content measurements, bone measurements, and carcass composition of gilts and barrow weanling pigs. Journal of Animal Science 72, 26702680.CrossRefGoogle ScholarPubMed
Krause, DO, Harrison, PC & Easter, RA (1994) Characterization of the nutritional interactions between organic acids and inorganic bases in the pig and chick. Journal of Animal Science 72, 12571262.CrossRefGoogle ScholarPubMed
Letendre, M, Girard, CL, Matte, JJ & Bernier, JF (1991) Effect of intramuscular injections of folic acid on folates status and growth performance of weanling pigs. Canadian Journal of Animal Science 71, 12231231.CrossRefGoogle Scholar
Lide, DR (19891980) CRC Handbook of Chemistry and Physics, 70th ed. Boca Raton, FL: CRC Press.Google Scholar
Lindemann, MD (1993) Supplemental folic acid: a requirement for optimizing swine reproduction. Journal of Animal Science 71, 239246.CrossRefGoogle ScholarPubMed
Littell, RC, Milliken, GA, Stroup, WW & Wolfinger, RD (1996) SAS® System for Mixed Models. Cary, NC: SAS Institute Inc.Google Scholar
Lueck, E (1980) Antimicrobial Food Additives: Characteristics, Uses, Effects. Berlin, Germany: Springer-Verlag.CrossRefGoogle Scholar
Lupton, JR & Kurtz, PP (1993) Relationship of colonic luminal short-chain fatty acids and pH to in vivo cell proliferation in rats. Journal of Nutrition 123, 15221530.CrossRefGoogle ScholarPubMed
McDonald, P, Edwards, RA, Greenhalgh, JFD & Morgan, CA (1995) Animal Nutrition, 5th ed. London: Longman Scientific & Technical.Google Scholar
Makar, AB, Tephly, TR, Sahin, G & Osweiler, G (1990) Formate metabolism in young swine. Toxicology and Applied Pharmacology 105, 315320.CrossRefGoogle ScholarPubMed
Maner, JH, Pond, WG, Loosli, JK & Lowrey, RS (1962) Effect of isolated soybean protein and casein on the gastric pH and rate of passage of food residues in baby pigs. Journal of Animal Science 21, 4952.CrossRefGoogle Scholar
Marsman, KE & McBurney, MI (1996) Dietary fiber and short-chain fatty acids affect cell proliferation and protein synthesis in isolated rat colonocytes. Journal of Nutrition 126, 14291437.CrossRefGoogle ScholarPubMed
Mathew, AG, Sutton, AL, Scheidt, AB, Forsyth, DM, Patterson, JA & Kelly, DT (1991) Effects of a propionic acid containing feed additive on performance and intestinal microbial fermentation of the weanling pig. In Digestive Physiology in Pigs: Proceedings of the Vth International Symposium, EAAP Publication no. 54, pp. 464469. Wageningen, The Netherlands: Pudoc.Google Scholar
Maxwell, FJ & Stewart, CS (1995) The microbiology of the gut and the role of probiotics. In The Neonatal Pig: Development and Survival, pp. 155186 [Varley, MA, editor]. Wallingford, Oxon.: CAB International.Google Scholar
Mayer, EA (1994) The physiology of gastric storage and emptying. In Physiology of the Gastrointestinal Tract, 3rd ed., vol. 1, pp. 929976 [Johnson, LR, Alpers, DH, Christensen, J and Jacobsen, E, editors]. New York: Lippencott Raven Press.Google Scholar
Mosenthin, R, Sauer, WC, Ahrens, F, de Lange, CFM & Bornholdt, U (1992) Effect of dietary supplements of propionic acid, siliceous earth or a combination of these on the energy, protein and amino acid digestibilities and concentrations of microbial metabolites in the digestive tract of growing pigs. Animal Feed Science and Technology 37, 245255.CrossRefGoogle Scholar
Mroz, Z, Grela, ER, Krasucki, W, Kies, AK & Schöner, FJ (1998) Microbial phytase in combination with formic acid for reproductive sows. Journal of Animal Science 76, Suppl. 1, 177 Abstr.Google Scholar
Mroz, Z, Jongbloed, AW, Partanen, K, van Diepen, JThM, Kemme, PA & Kogut, J (1997) Apparent digestibility of amino acids and balance of nitrogen and minerals as influenced by buffering capacity and organic acids in diets for growing swine. Journal of Animal Science 75, Suppl. 1, 185 Abstr.Google Scholar
Mroz, Z, Jongbloed, AW, Vreman, K, Canh, TT, van Diepen, JThM, Kemme, PA, Kogut, J & Aarnink, AJA (1996) The Effect of Different Dietary Cation-anion Supplies on Excreta Composition and Nutrient Balance in Growing Pigs. Report no. 96.028. Lelystad, The Netherlands: Institute of Animal Science and Health.Google Scholar
Nabuurs, MJ A (1995) Microbiological, structural and functional changes of the small intestine of pigs at weaning. Pig News and Information 16, 93N97N.Google Scholar
Øverland, M & Lysø, A (1997) Addition of formic acid and|or formates in diets for growing-finishing pigs. 48th Annual Meeting of the EAAP, p. 6.Google Scholar
Pallauf, J, Göttert, W & Krämer, K (1988) Influence of citric acid on the digestibility of nutrients and N balance in piglets. Deutsche Tierärztliche Wochenschrift 95, 146150.Google Scholar
Paulicks, BR, Roth, FX & Kirchgessner, M (1996) Dose effects of potassium diformate (FormiTM LHS) on the performance of growing piglets. Agribiological Research 49, 318326.Google Scholar
Petersen, U & Oslage, HJ (1982 a) Effect of fumaric acid alone or in combination with other growth promoters in pig production. 1. Optimal dosages of fumaric acid in relation to the type of ration. Landbauforschung Völkenrode 32, 149151.Google Scholar
Petersen, U & Oslage, HJ (1982 b) Effect of fumaric acid alone or in combination with other growth promoters in pig production. 3. Animal performance during application and after withdrawal of either fumaric acid or a combination of growth promoters. Landbauforschung Völkenrode 32, 157161.Google Scholar
Petito, SL & Evans, JL (1984) Calcium status of the growing rat as affected by diet acidity from ammonium chloride, phosphate and protein. Journal of Nutrition 114, 10491059.CrossRefGoogle ScholarPubMed
Pluske, JR, Williams, IH & Aherne, FX (1996) Maintenance of villous height and crypt depth in piglets by providing continuous nutrition after weaning. Animal Science 62, 131144.CrossRefGoogle Scholar
Pölönen, IJ, Vahteristo, LT & Tanhuanpää, EJ (1997) Effect of folic acid supplementation on folate status and formate oxidation rate in mink (Mustela vision). Journal of Animal Science 75, 15691574.CrossRefGoogle ScholarPubMed
Radcliffe, JS, Zhang, Z & Kornegay, ET (1998) The effects of microbial phytase, citric acid, and their interaction in a corn-soybean meal-based diet for weanling pigs. Journal of Animal Science 76, 18801886.CrossRefGoogle Scholar
Radecki, SV, Juhl, MR & Miller, ER (1988) Fumaric and citric acids as feed additives in starter pig diets: effect on performance and nutrient balance. Journal of Animal Science 66, 25982605.CrossRefGoogle ScholarPubMed
Ravindran, V & Kornegay, ET (1993) Acidification of weaner pig diets: a review. Journal of the Science of Food and Agriculture 62, 313322.CrossRefGoogle Scholar
Risley, CR, Kornegay, ET, Lindemann, MD & Weakland, SM (1991) Effects of organic acids with and without a microbial culture on performance and gastrointestinal tract measurements of weanling pigs. Animal Feed Science and Technology 35, 259270.CrossRefGoogle Scholar
Risley, CR, Kornegay, ET, Lindemann, MD, Wood, CM & Eigel, WN (1992) Effect of feeding organic acids on selected intestinal content measurements at varying times postweaning in pigs. Journal of Animal Science 70, 196206.CrossRefGoogle ScholarPubMed
Risley, CR, Kornegay, ET, Lindemann, MD, Wood, CM & Eigel, WN (1993) Effect of feeding organic acids on gastrointestinal digesta measurements at various times postweaning in pigs challenged with enterotoxigenic Escherichia coli. Canadian Journal of Animal Science 73, 931940.CrossRefGoogle Scholar
Roth, FX, Eckel, B, Kirchgessner, M & Eidelsburger, U (1992 a) Influence of formic acid on pH, dry matter content, and concentrations of volatile fatty acids and lactic acid in the gastrointestinal tract. 3. Nutritive value of organic acids in piglet rearing. Journal of Animal Physiology and Animal Nutrition 67, 148156.CrossRefGoogle Scholar
Roth, FX, Eidelsburger, U & Kirchgessner, M (1992 b) Influence of fumaric acid, hydrochloric acid, sodium formate, tylosin and toyocerin on pH, dry matter content, concentration of carbonic acids and ammonia in different segments of the gastrointestinal tract. 12. Nutritive value of organic acids in piglet rearing. Journal of Animal Physiology and Animal Nutrition 68, 93103.CrossRefGoogle Scholar
Roth, FX & Kirchgessner, M (1982) The nutritive value of Ca propionate in diets for piglets and fattening pigs. Wirtschaftseigene Futter 28, 235242.Google Scholar
Roth, FX & Kirchgessner, M (1988) Use of acetic acid in pig nutrition. Landwirtschaftliche Forschung 41, 253258.Google Scholar
Roth, FX & Kirchgessner, M (1989) Significance of dietary pH and buffering capacity in piglet nutrition. 1. pH and buffering capacity in diets supplemented with organic acids. Landwirtschaftliche Forschung 42, 157167.Google Scholar
Roth, FX, Kirchgessner, M & Eidelsburger, U (1993) Nutritive value of lactic acid in piglet rearing. Agribiological Research 46, 229239.Google Scholar
Roth, FX, Kirchgessner, M & Paulicks, BR (1996) Nutritive use of feed additives based on diformates in the rearing and fattening of pigs and their effects on performance. Agribiological Research 49, 307317.Google Scholar
Sakata, T (1987) Stimulatory effect of short-chain fatty acids on epithelial cell proliferation in the rat intestine: a possible explanation for trophic effects of fermentable fibre, gut microbes and luminal trophic factors. British Journal of Nutrition 58, 95103.CrossRefGoogle ScholarPubMed
Sakata, T, Adachi, M, Hashida, M, Sato, N & Kojima, T (1995) Effect of n-butyric acid on epithelial cell proliferation of pig colonic mucosa in short-term culture. Deutsche Tierärztliche Wochenschrift 102, 163164.Google ScholarPubMed
Sano, H, Nakamaura, E, Takahashi, H & Terashima, Y (1995) Plasma insulin and glucagon responses to acute challenges of acetate, propionate, n-butyrate and glucose in growing gilts (Sus scrofa). Comparative Biochemistry and Physiology 110A, 375378.CrossRefGoogle Scholar
Schulz, E & Fischer, F-W (1983) Use of different kinds of acidified skim milk in the fattening of pigs. Landbauforschung Völkenrode 33, 2226.Google Scholar
Schulz, E & Oslage, HJ (1982) Effect of fumaric acid alone or in combination with other growth promoters in pig production. 2. Combined effect of fumaric acid and antibiotics (Avoparsin). Landbauforschung Völkenrode 32, 152156.Google Scholar
Scipioni, R, Zaghini, G & Biavati, B (1978) The use of acidified diets for early weaning of piglets. Zootecnica e Nutrizione Animale 4, 201218.Google Scholar
Smith, HW & Jones, JET (1963) Observations on the alimentary tract and its bacterial flora in healthy and diseased pigs. Journal of Pathology and Bacteriology 86, 387412.CrossRefGoogle ScholarPubMed
Solomon, TE (1994) Control of exocrine pancreatic secretion. In Physiology of the Gastrointestinal Tract, 3rd ed. vol. 2, pp. 929976 [Johnson, LR, Alpers, DH, Christensen, J and Jacobsen, E, editors]. New York: Lippencott Raven Press.Google Scholar
Straw, ML, Kornegay, ET, Evans, JL & Wood, CM (1991) Effects of dietary pH and phosphorus source on performance, gastrointestinal tract digesta, and bone measurements of weanling pigs. Journal of Animal Science 69, 44964504.CrossRefGoogle ScholarPubMed
Stryer, L (1988) Biochemistry, 3rd ed. New York: WH Freeman and CompanyGoogle Scholar
Tephly, TR (1991) The toxicity of methanol. Life Sciences 48, 10311041.CrossRefGoogle ScholarPubMed
Thacker, PA & Bowland, JP (1980) Influence of graded levels of dietary propionic acid on performance and carcass traits of swine fed diets supplemented with soybean meal or canola meal. Canadian Journal of Animal Science 60, 971978.CrossRefGoogle Scholar
Thacker, PA & Bowland, JP (1981) Effects of vitamin B12 on performance and carcass traits of pigs fed diets supplemented with propionic acid or calcium propionate. Canadian Journal of Animal Science 61, 775782.CrossRefGoogle Scholar
Thacker, PA, Campbell, GL & Groot, Wassink J (1992) The effect of organic acids and enzyme supplementation on the performance of pigs fed barley-based diets. Canadian Journal of Animal Science 72, 395402.CrossRefGoogle Scholar
Thacker, PA, Salomons, MO, Aherne, FX, Milligan, LP & Bowland, JP (1981) Influence of propionic acid on the cholesterol metabolism of pigs fed hypercholesterolemic diets. Canadian Journal of Animal Science 61, 969975.CrossRefGoogle Scholar
Thomlinson, JR & Lawrence, TLJ (1981) Dietary manipulation of gastric pH in the prophylaxis of enteric disease in weaned pigs: Some field observations. Veterinary Record 109, 120122.CrossRefGoogle ScholarPubMed
Tschierschwitz, A, Grassmann, E, Kirchgessner, M & Roth, FX (1982) The effect of fumaric acid supplements on activities of liver enzymes (GOT, GPT, SUCCDH) with different supplies of energy and protein to growing rats. Zeitschrift für Tierphysiologie, Tierernährung und Futtermittelkunde 48, 253259.CrossRefGoogle Scholar
Weeden, TL, Nelssen, JL, Hansen, JA & Richardson, KL (1991) The effect of diet acidification on starter performance and nutrient digestibility. Journal of Animal Science 69, Suppl. 1, 105106.Google Scholar
Wohlt, JE, Jasaitis, DK & Evans, JL (1987) Use of acid and base titrations to evaluate the buffering capacity of ruminant feedstuffs in vitro. Journal of Dairy Science 70, 14651470.CrossRefGoogle Scholar
Wolffram, S, Bisang, B, Grenacher, B & Scharrer, E (1990) Transport of tri- and dicarboxylic acids across the intestinal brush border membrane of calves. Journal of Nutrition 120, 767774.CrossRefGoogle ScholarPubMed
Wolffram, S, Hagemann, C, Grenacher, B & Scharrer, E (1992) Characterization of the transport of tri- and dicarboxylates by pig intestinal brush-border membrane vesicles. Comparative Biochemistry and Physiology 101A, 759767.CrossRefGoogle Scholar
Zhang, J, Pettigrew, JE, Chester-Jones, H, Cornelius, SG & Moser, RL (1986) Efficacy of sodium diacetate as a growth promotant for swine. Nutrition Reports International 33, 893898.Google Scholar