期刊名称：Western Australia. Fisheries Department. Fisheries Research Reports
印刷版ISSN：1035-4549
出版年度：2008
卷号：178
页码：333-333
出版社：Government of Western Australia / Department of Fisheries
摘要：The experiment aimed to assess the effect of plant proteins on the gastrointestinal evacuation
rate (GIER) of Atlantic salmon (Salmo salar L.) smolts (144.2 ¡À 5.8 g) held at 15¡ãC. Ingredients
tested were L. luteus protein concentrate (LPC), L. luteus (cv Wodjil) kernel meal (LKM),
L. angustifolius (cv. Belara) kernel meal (BKM), L. angustifolius (cv. Myallie) kernel meal
(MKM), soybean meal (SBM). A reference mash that included an inert marker (0.1%) was
formulated and 5 experimental diets made to include 30% of each plant protein ingredient.
Two sets of each diet containing either 0.1% Yttrium oxide or 0.1% Ytterbium oxide as inert
markers were made. Calculation of the GIER was based on the replacement of one marker with
the second marker in faeces collected after the markers were changed in the diets being fed. A
model described by marker (%) = (a – d) / ((1 + (T/c) -b) + d) was used to derive values for the
slope (parameter b) of an S-shaped curve and the time taken for the second marker to replace
half the first marker (parameter c). In relation to the time taken for 50% replacement (parameter
c), the ingredients were divided into two groups: the kernel meals (LKM, BKM, MKM) had
values of 8.5 to 8.8 h compared with 10.2 to 11.4 h for the other ingredients (LPC, REF, SBM).
Groupings in the slope value (parameter b) were less obvious although the kernel meals had
the lowest values and LPC had the highest value, almost twice that of the lowest, MKM. The
higher slope values indicated more of the gut contents tended to be evacuated together whereas
the lower slope values indicated a more gradual evacuation. Apparent digestibility for dietary
nitrogen was positively correlated with slope (r = 0.829; P < 0.01; n = 6). Overall, the analysis
suggested that more of the lupin kernel meals were evacuated sooner but in a more gradual
manner. In comparison, the other meals, particularly LPC, remained in the gastrointestinal tract
longer but were then evacuated more rapidly in a consolidated mass.
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