Page 17 - New additives and ingredients in the formulation of aquafeeds

spp. enhance disease resistance, growth and water quality. Similarly, the
use of Ecobiol Aqua (B. amyloliquefaciens) is having successful use in shrimp
production; not only due to the benefits observed at farm level, but also
due to the stability and high survival of the finished product under pelleting
temperatures (<95°C).
Table 3. Performance parameters of Litopenaeus vannamei supplemented
with 1 kg Ecobiol Aqua/ton feed at commercial scale in Mexico
Trial 1 Trial 2
Control Ecobiol
Aqua
Difference
(%) Control Ecobiol
Aqua
Difference
(%)
Culture days 101 97 - 4.0 80 80
Average
weekly gain
(g)
- - - 1.33 1.51 + 13.5
Average
weight at 95
days (g)
13.30 13.83 + 4.0 - - -
Survival (%) 80.90 83.90 + 3.7 67.5 66.5 - 1.5
Income (US$/
Ha) 3245.2 3618,8 + 11.4 2841.0 3046.4 + 7.2
Dosage: 1 kg/ton of feed
Organic acid
salts
An organic acid is an organic compound with acidic properties associated
to the carboxyl group –COOH. Organic acids, proposed as candidate
replacement for antibiotics, have been used in terrestrial animal diets for
decades. Although the consistency of the effects on performance achieved
by antibiotics is difficult to emulate, organic acids may provide many of the
benefits of antibiotics naturally, hence the term NGPs. The antimicrobial
and antifungal activity is associated to weak and short-chain organic acids
(SCOA) (C1-C7) and highly dependent on concentration and pH. Thus, SCOA
such as acetic (C2), propionic (C3), butyric (C4), valeric (C5) and citric (C6)
differ in pKa value and consequently in its capability to reduce pH and inhibit
pathogens at the different physiological conditions encountered within the
gastrointestinal tract (Table 4). However, the effects of SCOA go beyond
modification of gutmicroflora, and other benefits such as improved digestive
enzyme activity, increased pancreatic secretion, enhanced development of
intestinal epithelium and intestinal barrier integrity, or anti-inflammatory
properties, have been described and attributed to likely causes of enhanced
performance when supplementing some of these NGPs, particularly butyric
acid in its sodium salt form.
Natural growth promoters in aquaculture practices 15