Synchronising the availability of amino acids and glucose increases protein retention in pigs
Van den Borne, J. J. G. C., Schrama, J. W., Heetkamp, M. J. W., Verstegen, M. W. A., Gerrits, W. J. J. (2007) Animal 1: 666-674
25-Oct-2007 (18 years 7 months 13 days ago)For an optimal protein deposition, in growing animals, is necessary a balanced
supply of amino acids and energy-yielding nutrients. The objective of this study
was to test if the efficiency of protein deposition could be reduced with a complete
separation of dietary protein and carbohydrate intake within the day.
To achieve the objective ten crossbred barrows (50 kg weight) were studied for
two experimental periods and each period were fed one of the two experimental
diets, in a change-over design. Experimental treatments consisted in a synchronous
supply of protein and starch (SYN), or an asynchronous supply of protein and starch
(ASYN), being the daily supply of nutrients and ingredients similar between the
two experimental treatments. The pigs assigned to SYN received the same diet two
times a day (8h and 16h), while those assigned to ASYN treatment received 95%
of the daily protein and 0% of the daily starch at 8h and 5% of daily protein
and 100% of daily starch at 16h. During the experimental period, it was measured
the average feed intake, and the average gain. Faecal apparent digestibility of
dietary components was studied, and nitrogen and energy balances were carried
out. Also, the nutrient utilization was studied by controlling the gas exchange.
Average feed intake and average gain were not different between the treatments.
The apparent digestibility of dry matter, organic matter and energy was lower
in ASYN treatment compared to SYN treatment, due to the increased digestibility
of non-starch polysaccharides in the SYN treatment. The nitrogen retention and
the efficiency of utilisation of digestible protein for protein gain were lower
for ASYN than for SYN. Respiratory quotients obtained showed that animals fed
in the ASYN treatment had a higher oxidation of fat and aminoacids, specially
after the morning meal, due to the lack of glucose. Heat production was higher
in the ASYN diet, indicating that a substantial part of the increased quantity
of amino acids was oxidised.