A duo of researchers from Denmark reported the results of feed trials using the novel ingredient in the journal Animal Feed Science and Technology.
The inclusion of starfish meal (SM) as an alternative protein source at certain levels prompted similar growth for piglets as more traditional feedstuffs meaning it could act as a partial substitute, they said.
“Feeding 50 g SM/kg resulted in a performance equal to pigs fed the control diets,” concluded researchers. “Inclusion of 100 g SM/kg in the diet affected performance negatively due to a wide Ca:P affecting digestibility and absorption of P negatively. Thus, the determining factor for the maximum inclusion level of SM in diets for piglets may be the dietary Ca level and the resulting Ca:P in relation to the nutritional requirements.”
Starfish meal
With the increase in demand for protein feed ingredients, producers have to be open to alternative products, said researchers. Additionally, interest is growing in finding sustainable or locally available protein sources.
In Denmark, starfish offer one such local, alternative protein source, they said. “Starfish in high concentrations are considered pests by the commercial mussel farmers,” they added.
The use of starfish meal for poultry feed was studied and found similar to fishmeal, they said. However use in pig diets has not been reported.
The standardized ileal digestibility (SID) of crude protein, chemical makeup and amino acid levels make the meal attractive for inclusion in pig feed, said researchers.
“It was hypothesised that feeding a diet containing SM will generate the same average daily feed intake (ADFI), average daily gain (ADG) and gain to feed ratio (G:F) as traditional diets containing [fish meal] FM or extruded soybean meal (ESBM),” said researchers. “The objective of the present study was, therefore, to evaluate if piglets fed a diet containing SM as a protein source perform on equal terms as pigs fed traditional diets for piglets.”
Experiment details
In the experiment 96 pigs were fed one of four diets containing separate protein sources for 14 days, said researchers. The sources included fish meal (FM), extruded soybean meal (ESBM) and two levels of SM – SM50 and SM100.
“Since all diets were formulated to contain approximately 200 g CP/kg, SM as such could not, besides SBM, be fed as a sole protein source without increasing the Ca level of the diet substantially,” said researchers. “Therefore, SM was mixed with ESBM leading to one diet containing 50 g SM/kg (SM50) and another containing 100 g SM/kg (SM100).”
The starfish meal was prepared using locally caught and processed starfish, they said. It was dried and ground into meal prior to being used.
Average daily feed intake (ADFI), average daily gain (ADG) and the gain to feed ratio (G:F) were calculated, they said.
Manure was scored evaluated on days 5 through 9 and blood samples were taken on day 15 to check for plasma urea nitrogen, amino acids (AA), calcium (Ca) and phosphorus (P), they said. Pigs were weighed on days 0, 7 and 14.
Results
“The SM was characterized by containing 383 g CP/kg DM [dry matter] and 421 g ash/kg DM, whereas e.g. FM contained 735 g CP/kg DM and 171 g ash/kg DM,” said researchers. “The protein fraction of SBM, FM, ESBM and SM was analyzed for AA, and the content of the individual AA in relation to CP, i.e. the AA profile, was comparable among the protein sources.”
No differences in the fecal matter were found for the piglets in the different groups, said researchers. And ADFI did not differ among groups.
ADG and G:F were similar for piglets getting FM, ESBM and SM50 diets, they said. But ADG was lower for pigs getting the SM100 diet.
“Plasma urea nitrogen in SM100 was higher than the concentrations in ESBM and SM50 but not FM,” said researchers. “Plasma Ca concentration was higher in pigs receiving SM100 compared to FM, ESBM and SM50.”
The phosphorus concentration was lower for piglets on the SM100 diet when compared to those getting the FM, ESBM and SM50 diets, they said.
Source: Animal Feed Science and Technology
Title: Starfish (Asterias rubens) as feed ingredient for piglets
DOI: published online ahead of print: 10.1016/j.anifeedsci.2015.11.012
Authors: P. Sørensen, J.V. Nørgaard