Page 18 - New additives and ingredients in the formulation of aquafeeds

Table 4. Organic acids used as additives in animal nutrition
Acid Formula Molecular mass (g/mol) pKa
Formic HCOOH 46.03 3.75
Acetic CH3 COOH 60.05 4.76
Propionic CH3 CH2 COOH 74.08 4.88
Butyric CH3 CH2 CH2 COOH 88.12 4.82
Lactic CH3 CH(OH)COOH 90.08 3.83
Fumaric COOHCH:CHCOOH 116.07 3.02
4.38
Malic COOHCH 2 CH(OH)COOH 134.09 3.40
5.10
Tartaric COOHCH(OH)CH(OH)COOH 150.09 2.93
4.23
Valeric CH3 CH2CH2 CH 2COOH 102.13 4.84
Citric COOHCH 2 C(OH)(COOH)CH2 COOH 192.14 3.13
4.76
Concerning the use, most of the SCOA are characterized by volatility
and corrosiveness, being a problem at the feed mill level where feed is
processed under high temperatures. Accordingly, salt forms of SCOA are
commercialized, providing convenient storage, stability through processing
and consequently high recovery in the pelleted or extruded feed. When it
comes to aquaculture a number of studies covering both cold-water and
tropical species indicate that a broad range of organic acids, their salts or
mixtures of those, can improve growth, feed utilization, disease resistance,
and consequently the benefits of the producer (Table 5).
Table 5. Studies using organic acids, either in acid or salt form, in both cold
and warm water species
Species Benefit Reference
Artic charr Improved FCR
Enhanced health status (diarrhoea)
Ringø (1991)
Ringø et al. (1994)
Gislason et al. (1996)
Atlantic
salmon
Enhanced mineral absorption
Improved FCR
Gislason et al. (1994)
Gislason et al. (1996)
Christiansen and Lückstädt (2008)
Rainbow
trout
Enhanced mineral absorption
Improved growth rate and FCR
Vielma and Lall (1997)
Sugiura et al. (1998a)
Sugiura et al. (1998b)
Vielma et al. (1999)
Tilapia Improved growth rate, FCR and
PER
Ramli et al. (2005)
Zhou et al. (2008)
Petcam et al. (2008)
Carp Reduced intestinal digesta pH
Better mineral availability
Improved growth rate and FCR
Baruah et al. (2005)
Baruah et al. (2007)
Catfish Improved growth rate and FCR Owen et al. (2006)
16 Natural growth promoters in aquaculture practices