Two experiments were conducted by A.B. Graham and colleagues at Kansas State Univeristy to determine the amino acid and gross energy digestibility of fermented soybean meal and camelina meal.

For Experiment 1, to determine standardized ileal amino acid digestibility, five growing gilts (bodyweight = 60.4 lb) were surgically fitted with T-cannulas at the terminal ileum and randomly allotted to one of three dietary treatments in a cross-over design with three periods.

The basal diets were corn starch–based with adequate vitamins and minerals to meet the pigs’ requirements. The experimental treatments consisted of the basal diet with 30 per cent fermented soybean meal or 39.25 per cent camelina meal as the sole protein source. A third nitrogen-free diet was also fed to determine basal endogenous amino acid losses.

Experiment 2 aimed to determine energy concentrations. Six growing barrows (bodyweight = 64.8 lb) were randomly allotted to one of three dietary treatments in a cross-over design with three periods. The corn-based treatment diets had 25 per cent fermented soybean meal or 30 per cent camelina meal. A third corn basal diet was also offered to allow for energy calculations by the difference method. All diets contained 0.25 per cent titanium oxide as an indigestible marker.

Digesta samples were collected and analysed for amino acid concentrations and faecal samples were collected and analysed for energy concentrations. After chemical analysis, standardised and apparent ileal digestible (SID and AID, respectively) amino acids were determined, and Digestible Energy (DE), Metabolisable Energy (ME) and Net Energy (NE) were calculated for each ingredient.

On a dry matter basis, GE, DE, ME and NE were 1,973, 1,377, 1,232, and 880kcal per lb, respectively, for fermented soybean meal and 2,075, 1,150, 1,041, and 715kcal per lb, respectively, for camelina meal.

In fermented soybean meal, the AID for lysine, methionine, threonine, and tryptophan were 63.5±7.5, 84.6±1.0, 74.0±3.5 and 81.8±1.4 per cent, respectively, and SID values were 71.1±6.2, 89.2±2.1, 88.0±3.1 and 93.7±2.0 per cent, respectively.

For camelina meal, the AID for lysine, methionine, threonine and tryptophan were 47.3±7.7, 74.6±3.3, 39.7±6.8 and 67.3±8.3 per cent, respectively, and SID values were 53.9±6.4, 77.7±3.5, 51.6±6.7 and 79.7±6.8 per cent, respectively.

The SID availability for amino acids in fermented soybean meal were relatively high and similar to published values for soybean meal, with the exception of lysine, concluded Graham and co-authors. Standardised ileal digestible amino acid availability values for camelina meal, however, were low, indicating that it may have contained the high glucosinolate concentrations generally observed in camelina meal.

Reference

Graham A.B., J.M. DeRouchey, R.D. Goodband, M.D. Tokach, S.S. Dritz and R.C. Thaler. 2013. Amino acid digestibility and energy concentration of fermented soybean meal and camelina meal for swine. Proceedings of 2013 Kansas Swine Day, p247-255.

April 2014