Torula yeast has greater digestibility of amino acids and phosphorus, but not energy, compared with a commercial source of fish meal fed to weanling pigs

Abstract

Three experiments were conducted to test the hypothesis that the standardized ileal digestibility (SID) of AA, concentrations of DE and ME, and the standardized total tract digestibility (STTD) of P in a source of torula yeast are not different from values obtained in Menhaden fish meal. In experiment 1, six weanling barrows (initial BW: 11.7 ± 0.4 kg) were prepared with a T-cannula in the distal ileum and allotted to a replicated 3 × 3 Latin square design with 3 diets and 3 periods. In each period, there were 5 d of adaptation and 2 d of collection. Two cornstarch-based diets using the torula yeast or fish meal as the sole source of AA and a N-free diet were formulated. The SID of CP and all AA was greater (P < 0.05) in torula yeast than in fish meal. In experiment 2, 24 weanling barrows (initial BW: 14.4 ± 1.1 kg) were individually housed in metabolism crates and allotted to a corn-based diet or 2 diets based on a mixture of corn and torula yeast or corn and fish meal. Feces and urine samples were collected for 4 d following a 5-d adaptation period. There were 8 replicate pigs per diet and fecal and urine materials were collected. Results of this experiment indicated that there were no differences in the concentration of DE and ME (DM basis) between torula yeast and fish meal. In experiment 3, a total of 32 weanling barrows (initial BW: 11.9 ± 1.1 kg) were allotted to 4 diets and 8 replicate pigs per diet. Pigs were placed in individual metabolism crates. The torula yeast or fish meal were used in 2 diets containing either 0 or 500 units of microbial phytase. Feces samples were collected as described for experiment 2. The STTD of P in torula yeast was greater (P < 0.05) than in fish meal, but regardless of ingredient, there was no effect of the inclusion of phytase in the diets. In conclusion, the SID of AA and the STTD of P in torula yeast is greater than in fish meal, but values for the concentration of DE and ME in torula yeast are not different from those in fish meal. Therefore, the torula yeast that was used in the present experiments may be included at the expense of fish meal in diets fed to weanling pigs if the concentration of standardized ileal digestible AA is considered in the formulation.

Digestibility of amino acids in fish meal and blood-derived protein sources fed to pigs

“…The analyzed CP, AA, and ash concentrations in FM are consistent with the previously reported values [ 9 , 14 , 15 ]. In addition, the concentration of AEE in FM also agrees with the values reported in Casas et al [ 14 ] and Lagos and Stein [ 15 ].…”

“…The analyzed CP, AA, and ash concentrations in FM are consistent with the previously reported values [ 9 , 14 , 15 ]. In addition, the concentration of AEE in FM also agrees with the values reported in Casas et al [ 14 ] and Lagos and Stein [ 15 ]. The FM used in the current study is representative due to similarity in AA concentration for FM reported in previous studies [ 9 , 14 , 15 ].…”

“…In addition, the concentration of AEE in FM also agrees with the values reported in Casas et al [ 14 ] and Lagos and Stein [ 15 ]. The FM used in the current study is representative due to similarity in AA concentration for FM reported in previous studies [ 9 , 14 , 15 ]. The concentration of AA in SDPP are comparable to the values for plasma protein [ 9 ] and the values for SDAP [ 16 ] despite the differences in source of blood plasma.…”

“…The BEL of proline was relatively greater than the BEL of other AA, which may be due to the altered AA metabolism in the gastrointestinal tract caused by deficiency of AA in pigs fed NFD [ 22 ]. The SID of CP and AA in FM are close to the SID values of menhaden FM reported in Rojas et al [ 23 ] and Casas et al [ 14 ], but somewhat greater than SID values of menhaden FM presented by Lagos and Stein [ 15 ]. This inconsistency may be due to the differences in BW of pigs used in experiments or FM products such as processing conditions or oxidation [ 3 ].…”

Composition and thermal processing evaluation of yeast ingredients as thiamin sources compared to a standard vitamin premix for canned cat food

“…Thiamin content of a dried brewer's torula yeast was 6.7 mg/kg DMB [1], which was lower than all six yeast ingredients screened in the present experiment. Crude protein and fat contents of all 6 yeasts fell in line with ingredients evaluated in animal feeding experiments [15,[27][28][29]. The FP ingredient contained notably high levels of crude fiber compared to the other yeast ingredients, which was expected.…”