Date Published: November 9, 2007
Publisher: BioMed Central
Author(s): Anne Louise F Hellwing, Anne-Helene Tauson, Anders Skrede.
The experiment investigated the effects of increasing dietary levels of bacterial protein meal (BPM) on various blood parameters reflecting protein and fat metabolism, liver function, and purine base metabolism in growing pigs. Sixteen barrows were allocated to four different experimental diets. The control diet was based on soybean meal. In the other three diets soybean meal was replaced with increasing levels of BPM, approximately 17%, 35%, and 50% of the nitrogen being derived from BPM. Blood samples from the jugular vein were taken when the body weights of the pigs were approximately 10 kg, 21 kg, 45 kg, and 77 kg. The blood parameters reflecting fat metabolism and liver function were not affected by diet. Both the plasma albumin and uric acid concentrations tended to decrease (P = 0.07 and 0.01, respectively) with increasing dietary BPM content, whereas the plasma glucose concentration tended to increase (P = 0.07) with increasing dietary BPM content. It was concluded that up to 50% of the nitrogen could be derived from BPM without affecting metabolic function, as reflected in the measured blood parameters.
Bacterial protein meal (BPM) is a new protein source fermented on natural gas, ammonia, and oxygen by Methylococcus capsulatus (Bath) (>90%), Ralstonia sp., Brevibacillus agri, and Aneurinibacillus sp. The protein content of BPM is 65–70% and the amino acid composition is comparable to those of fish meal and soybean meal . Rapidly growing bacteria may contain up to 25% nucleic acids on a dry matter basis . The nucleic acid (i.e., ribonucleic acid (RNA) and deoxyribonucleic acid (DNA)) content of BPM is approximately 10%, which is similar to that of yeast [3,4] but much higher than that of soybean meal or fish meal [5,6].
ALT: alanine aminotransferase, AST: aspartate aminotransferase, BPM: bacterial protein meal, DNA: deoxyribonucleic acid, HDL: high density lipoprotein, LDL: low density lipoprotein, N: nitrogen, RNA: ribonucleic acid, VLDL: very low density lipoprotein
The author(s) declare that they have no competing interests.
ALFH participated in experimental design, carried out the blood sampling and statistical analyses, and drafted the manuscript. AHT participated in the experimental design and in writing the manuscript. AS leads the strategic research programme (see below), and contributed to the experimental design and to writing the manuscript. All authors approved of the final manuscript.