Crude Protein Disappearance Research Articles

Effect of organic acids on fermentation quality and microbiota of horseshoe residue and corn protein powder

This experiment aimed to investigate the impact of malic acid (MA) and citric acid (CA) on the nutritional composition, fermentation quality, rumen degradation rate, and microbial diversity of a mixture of apple pomace and corn protein powder during ensiling. The experiment used apple pomace and corn protein powder as raw materials, with four groups: control group (CON), malic acid treatment group (MA, 10 g/kg), citric acid treatment group (CA, 10 g/kg), and citric acid + malic acid treatment group (MA, 10 g/kg + CA, 10 g/kg). Each group has 3 replicates, with 2 repetitions in parallel, subjected to mixed ensiling for 60 days. The results indicated: (1) Compared to the CON group, the crude protein content significantly increased in the MA, CA, and MA + CA groups (p < 0.05), with the highest content observed in the MA + CA group. The addition of MA and CA effectively reduced the water-soluble carbohydrate (WSC) content (p < 0.05). Simultaneously, the CA group showed a decreasing trend in NDFom and hemicellulose content (p = 0.08; p = 0.09). (2) Compared to the CON group, the pH significantly decreased in the MA, CA, and MA + CA groups (p < 0.01), and the three treatment groups exhibited a significant increase in lactic acid and acetic acid content (p < 0.01). The quantity of lactic acid bacteria increased significantly (p < 0.01), with the MA + CA group showing a more significant increase than the MA and CA groups (p < 0.05). (3) Compared to the CON group, the in situ dry matter disappearance (ISDMD) significantly increased in the MA, CA, and MA + CA groups (p < 0.05). All three treatment groups showed highly significant differences in in situ crude protein disappearance (ISCPD) compared to the CON group (p < 0.01). (4) Good’s Coverage for all experimental groups was greater than 0.99, meeting the conditions for subsequent sequencing. Compared to the CON group, the Shannon index significantly increased in the CA group (p < 0.01), and the Simpson index increased significantly in the MA group (p < 0.05). However, there was no significant difference in the Chao index among the three treatment groups and the CON group (p > 0.05). At the genus level, the abundance of Lentilactobacillus in the MA, CA, and MA + CA groups was significantly higher than in the control group (p < 0.05). PICRUSt prediction results indicated that the metabolic functional microbial groups in the CA and MA treatment groups were significantly higher than in the CON group (p < 0.05), suggesting that the addition of MA or CA could reduce the loss of nutritional components such as protein and carbohydrates in mixed ensilage. In conclusion, the addition of malic acid and citric acid to a mixture of apple pomace and corn protein powder during ensiling reduces nutritional losses, improves fermentation quality and rumen degradation rate, enhances the diversity of the microbial community in ensiled feed, and improves microbial structure. The combined addition of malic acid and citric acid demonstrates a superior effect.

155 Standardized ileal digestibility of amino acids in soybean meal, fermented soybean meal, and soy protein concentrate fed to nursery pigs

Abstract Accurate information of amino acid (AA) digestibility in protein supplements is critical in formulating diets for nursery pigs. Soybean products are widely used in nursery pig diets due to the high crude protein (CP) concentrations. The objective of the present study was to determine the standardized ileal digestibility (SID) of AA in soybean meal, 3 sources of fermented SBM (FSBM), and soy protein concentrate (SPC) fed to nursery pigs. Ten barrows with an initial body weight of 10.5 kg (standard deviation = 0.9) were surgically fitted with T-cannulas at the distal ileum. The animals were assigned to a replicated 5 × 5 Latin square design with 10 animals, 5 experimental diets, and 5 periods to obtain 10 observations per diet. Five diets were prepared to contain SBM (48.5% CP), 3 sources of FSBM (A, B, and C; 52.6% CP, 55.1% CP, and 49.8% CP, respectively), or SPC (58.4% CP) as the sole source of AA. Each period consisted of 4 d of adaptation period and 3 d of ileal digesta collection period. The values of basal endogenous losses of AA reported in the literature were used to calculate the SID of AA by correcting the apparent ileal digestibility (AID) values. Additionally, a 2-step in vitro procedure modified for nursery pigs was conducted to determine the in vitro ileal disappearance of CP in the 5 ingredients. The AID of all indispensable AA except His and Lys in FSBM-A and FSBM-B was greater (P &amp;lt; 0.05) than that in SBM, whereas AID values for all AA except Trp in SPC did not differ from the values in SBM. The SID of Leu and Trp in FSBM-A and FSBM-B was greater (P &amp;lt; 0.05) than that in SBM or SPC. The SID of all AA in SPC was not different from that in SBM. In vitro ileal disappearance of CP in 3 sources of FSBM was greater (P &amp;lt; 0.001) than that in SBM or SPC. In conclusion, in vitro ileal disappearance of protein was greater in fermented soybean meal compared with soybean meal or soy protein concentrate whereas the standardized ileal digestibility of most amino acids was comparable among the soybean-derived ingredients.

Isobutyramide and Slow-Release Urea as Substitutes for Soybean Meal in the Finishing Diet of Beef Cattle.

Two experiments were conducted to investigate the effects of isobutyramide (IBA) and slow-release urea (SRU) as substitutes for soybean meal (SBM) in the finishing diet of beef cattle. The completely randomized design in vitro experiment with five treatments, i.e., control, 0.9% SRU group, 0.6% SRU + 0.3% IBA group (SRU-I), 0.3% SRU + 0.6% IBA group (IBA-S), 0.9% IBA group was conducted. The results showed that the IBA-S and IBA increased (p ≤ 0.05) substrate disappearance of dry matter (DM), neutral detergent fiber (NDF), acid detergent fiber (ADF), total gas, and total volatile fatty acids (TVFA). The SRU group had the highest (p < 0.01) crude protein disappearance and ammonia nitrogen concentration, but the IBA contrarily decreased (p < 0.01) them compared with the control. Inclusion of IBA increased isobutyrate concentrations (p = 0.01) with the highest value for the IBA group. Then, an 84-day replicate 4 × 4 Latin square design with 8 Angus steers and four treatments, i.e., control, SRU, SRU-I, IBA-S was performed. The results showed that the treatments did not affect DM intake (p > 0.05) but tended (p = 0.09) to increase average daily gain. The inclusion of IBA increased (p < 0.05) the apparent digestibility of DM, organic matter, NDF, ADF, TVFA, and microbial crude protein with the highest values for the IBA-S group. The IBA-contained groups also increased (p ≤ 0.01) isobutyrate concentration, activities of carboxymethyl cellulase and xylanase, and the relative abundance of Butyrivibrio fibrisolvens with the highest values for the IBA-S group. The SRU had no effect on animal growth and nutrient apparent digestibility. In conclusion, IBA was developed as a new substitute for SBM in the finishing diet of beef cattle, and the optimal strategy was the isonitrogenous substitution of SBM with 0.3% SRU and 0.6% IBA of the diet.

232 In Vitro Digestibility of Dry Matter and Nitrogen of Napier Grass Silage Is Affected By Fertilization with Cow-Dung Bio-Digester Slurry and Fermentable Carbohydrate Additives at Ensiling

Abstract The use of silages during the dry season could ameliorate major nutritional constraints in ruminant livestock production in tropical regions. Napier grass (Pennisetum purpureum) is a tropical forage source that is used for silage in South Africa. The present objective was to determine the effects of fertilization with bio-digester slurry (BDS) and of carbohydrate additives [no additive (control), molasses, brown sugar, and maize meal] at ensiling on in vitro digestibility of Napier grass silage. Fresh Napier grass irrigated weekly with either BDS or water was cut after 12 weeks and ensiled for 90 days in 1 liter glass jars in a 2 (control and slurry irrigation) x 4 (no additive, molasses, maize meal and brown sugar) factorial arrangement replicated three times. The nutrient composition was determined using standard protocols. The in vitro digestibility of dry matter (DM) and crude protein (CP) were determined by the three-stage method after incubation in rumen of steers for 12, 24 and 48-hour incubation. The bags containing rumen undegradable residuals (RURs) were removed from the bags, composited by treatment, and ground through a 1 mm sieve. Approximately 1g samples of RURs of each silage sample were placed in a 0.1 N HCl solution adjusted to pH 1.9 with 1 g ℓ-1 of pepsin, and then in pancreatin solution and rinsed with deionized water and dried at 60°C for 48 h. At 24 h incubation, the no BDS, no additive (control) treatment had the least (P &amp;lt; 0.01) DM degradability. As incubation time progressed to 48 h, fertilization with BDS with molasses inclusion increased (P &amp;lt; 0.05) DM disappearance. However, the BDS fertilization and carbohydrate additive interaction had no effect (P &amp;gt; 0.05) on 12 incubation h, and in vitro digestibility after 12, 24 and 48 h of incubation. Fertilization with BDS reduced (P &amp;lt; 0.05) DM digestibility after 48 hours of rumen incubation. Carbohydrate additives increased (P &amp;lt; 0.01) DM disappearance at 12, 24 and 48 rumen incubation h but did not not influence in vitro DM digestibility after 12, 24, and 48 h of rumen incubation. Fertilization with BDS and carbohydrate additives at ensiling interaction had no effect (P &amp;gt; 0.05) on CP degradability at 12, 24, and 48 h of rumen incubation, and in vitro CP digestibility after 12, 24, and 48 h of incubation. Carbohydrate additives increased (P &amp;lt; 0.01) CP disappearance at 12, 24 and 48 rumen incubation h and reduced (P &amp;lt; 0.01) in vitro CP digestibility after 12 h of rumen incubation but did not have an effect (P &amp;gt; 0.05) on in vitro CP digestibility after 24 and 48 h of rumen incubation.

PSIV-20 An in Vitro Digestion Procedure Using Daisyii Incubator Can Replace Conventional in Vitro Digestion Procedures Using Flasks for Estimating Ileal Digestibility of Feed Ingredients for Pigs

Abstract In vitro procedures using flasks have been used for simulating nutrient utilization by pigs. However, these procedures are time-consuming and laborious and require a number of flasks and filter crucibles. The objective of this study was to develop an in vitro procedure using DaisyII incubator for simultaneous analysis of multiple samples. In a conventional in vitro procedure, 10 mg of pepsin in step 1 and 50 mg of pancreatin in step 2 are used for each flask containing 1 g of feed sample. In a preliminary experiment, 24 samples each in R55 bags were digested in a jar of DaisyII incubator with 24 times the quantity of buffer solution and enzymes of the conventional flask procedure. In the preliminary experiment, greater crude protein (CP) digestibility values were observed in the DaisyII incubator procedure compared with the conventional flask procedure. To determine optimum enzyme doses in the in vitro ileal disappearance (IVIDDaisy) procedure using the DaisyII incubator, 3 doses of pepsin (10, 7.5, and 5 mg/sample in step 1) and 3 doses of pancreatin (50, 37.5, and 25 mg/sample in step 2) were tested in a 3 × 3 factorial arrangement for 11 test ingredients. The quantity of buffer solution and enzymes in a jar was increased proportionally with the number of samples. The 11 test ingredients were barley, copra meal, corn, corn distillers dried grains with solubles, corn gluten feed, corn gluten meal, palm kernel meal, rice bran, soybean hulls, soybean meal, and wheat bran. The in vitro ileal disappearance (IVIDflask) of CP in the 11 ingredients was determined using the conventional flask procedure. The sum of square of deviation between IVIDflask of CP and IVIDDaisy of CP was the least when 5 mg pepsin/sample in step 1 and 37.5 mg/sample in step 2 were used (IVIDflask of CP, % = 14.4 + 0.81 × IVIDDaisy of CP, %; r2 = 0.748). On the other hand, the determination coefficient was the greatest when 10 mg pepsin/sample in step 1 and 50 mg/sample in step 2 were used (IVIDflask of CP, % = 2.5 + 0.93 × IVIDDaisy of CP, %; r2 = 0.878). In conclusion, the in vitro procedure using a DaisyII incubator can be used for estimating ileal digestibility of protein in multiple samples simultaneously for pigs.

Evaluation of degradability of Moringa, Pineapple waste and Plantain herbs by in situ and in vitro gas production technique

Nutritional evaluation of feed ingredients is important for potential use in feed rations. It is very important to determine not only the nutrient content and quality of feeds but also their digestibility prior to adding in the ration. This study was undertaken to assess the potential nutritive value of selected shade-dried herbs of moringa, pineapple waste, and plantain through in situ degradation and in vitro gas production techniques. The study compared 4 treatments, namely moringa (MH), pineapple waste (PwH), plantain (PH) herbs, and a combination of three of them with a ratio of 1:1:1 (MxH). The rumen dry matter (DM) and crude protein (CP) degradability kinetics were analyzed by using the nylon bags (in situ) procedure and the organic matter digestibility and fermentation characteristics were analyzed by in vitro gas production technique. The results of the in situ study revealed that the ruminal dry matter disappearance differed significantly (P&lt;0.001) among herbs at all incubation periods whereas the PH had the greatest disappearance and PwH had the lowest among all herbs. Significantly (P&lt;0.05) the highest potential and effective degradability of dry matter were found in PH and the lowest in PwH among herbs. The ruminal CP disappearance differed significantly (p&lt;0.05) among herbs at all incubation periods. The MH had the greatest CP disappearance whereas PwH had the lowest. Significantly (P&lt;0.05) the highest potential and effective degradability of CP were found in MH and MxH, respectively, and the lowest in PwH among herbs. The results of the in vitro study revealed that cumulative gas production was increased with increasing the periods of incubation for all herbs. Significantly (P&lt;0.05) the highest gas production was found in PH and MH among all herbs at 48h of incubation. The organic matter digestibility and metabolizable energy were found significantly (P&lt;0.05) higher in MH &amp; PH and lower in PwH. Short-chain fatty acids were also significantly (P&lt;0.05) higher in MH &amp; PH and lower in PwH among herbs. It may be concluded that both plantain and moringa herbs showed better potential and effective degradability and also higher organic matter digestibility and metabolizable energy comparable to pineapple waste herbs. Bangladesh Journal of Animal Science 52 (3): 88-98.

Impact of adding tannins or medium-chain fatty acids in a dairy cow diet on variables of in vitro fermentation using a rumen simulation technique (RUSITEC) system

This work aimed to evaluate the effect of including 2 functional feed ingredients in a diet with a high proportion of pasture silage on in vitro ruminal fermentation, nutrient disappearances, and ruminal microbiomes. In a rumen simulation technique (RUSITEC) system (6 fermentation units), 4 treatments were evaluated: 1) CONTROL: a diet based on corn and grass silage, regular soybean meal (SBM), and corn; 178 g/kg of crude protein (CP) (used as negative control), 2) TSBM: Replacement of SBM by Mervobest® (used as positive control), 3) PHY (phytogenic mixture (tannins from quebracho and chestnut) at 10 g/kg dry matter (DM) replacing SBM) and 4) MCFA (mixture of medium-chain fatty acids, Aromabiotic Cattle® at 10 g/kg DM replacing SBM). Four runs were performed with 3 diets incubated simultaneously in duplicate using a balanced incomplete block design, lasting 17 days each. The inoculum was obtained from 3 rumen fistulated cows, and artificial saliva was infused at 650 mL/day. Samples were taken from each fermentation unit to determine the gas production, pH, NH3-N, and volatile fatty acids concentrations. The apparent digestibility of diet compounds was determined. Microbial protein synthesis and microbial community diversity were estimated using 15N as an external isotopic marker and by sequencing part of the 16 S rDNA gene, respectively. The TSBM and PHY treatments decreased NH3-N concentrations (P < 0.001) and the DM disappearance (P = 0.004). The crude protein disappearance was the lowest for TSBM followed by PHY (P < 0.001). The true protein disappearance was lower for TSBM and PHY than for CONTROL and MCFA (P < 0.001). The isovaleric acid proportion was lower for TSBM, MCFA, and PHY than for CONTROL. Treatments TSBM and MCFA registered lower neutral detergent fibre disappearance (P < 0.001) than the other diets but without changes in the quantified fibrolytic genera in the ruminal microbiota. The PHY treatment increased the relative abundance of Succinivibrio spp. and reduced that of Methanobrevibacter relative to that of CONTROL and TSBM, which could be linked to lower methanogenesis. The MCFA treatment increased Succinivibrio compared with TSBM and Succiniclasticum spp. compared with CONTROL. These results indicate that PHY inclusion at 10 g/kg DM decreased rumen protein degradation, similar to TSBM; while MCFA decreased rumen protein degradation to a lesser extent. Furthermore, both additives generated changes in the ruminal microbiota that would be associated with lower methane production.

Nutrient Digestibility of Soybean Meal Products Based on In Vitro Procedures for Pigs

The present work aimed to assess the nutrient digestibility of soybean meal (SBM) products based on in vitro procedures. Two-step and three-step in vitro assays were performed to mimic the digestion and absorption of nutrients in the digestive tracts of growing swine. The two-step in vitro method was modified to reflect the digesta retention time and digestive enzymes of nursery piglets by decreasing incubation periods and digestive enzymes to half of those in the procedure for growing pigs and was used to determine the crude protein (CP) digestibility of nursery piglets. The seven ingredients included conventional SBM, thermo-mechanically processed SBM (TSBM), and five sources of fermented SBM (FSBM). The five sources of FSBM were produced using different microorganisms for fermentation, namely: (1) Pediococcus pentosaceus and Bacillus subtilis, (2) Enterococcus faecium (FSBM-EF), (3) Aspergillus oryzae and Bacillus subtilis, (4) Aspergillus oryzae, and (5) Bacillus licheniformis. Based on the conventional procedure, the in vitro ileal disappearance of CP in TSBM was greater (p &lt; 0.05) compared with that in FSBM sources. Based on the in vitro assays for total tract digestibility, organic matter in TSBM was better digested (p &lt; 0.05) compared with that in FSBM except for FSBM-EF. Based on the in vitro procedure for nursery piglets, the ileal disappearance of CP in TSBM was greater (p &lt; 0.05) than that in the other SBM products. Taken together, thermo-mechanical processing rather than microbial fermentation of SBM improves the nutrient digestibility of SBM, particularly in nursery pigs.

Prediction Equations for In Vitro Ileal Disappearance of Dry Matter and Crude Protein Based on Chemical Composition in Dog Diets.

The aims of this study were to determine in vitro ileal disappearance (IVID) of dry matter (DM) and crude protein (CP) in commercial dog diets and to develop equations for predicting the IVID of DM and CP in dog diets based on chemical composition. Eighteen commercial dog diets were analyzed for IVID of DM and CP using a two-step in vitro procedure for dogs. The diet samples in flasks with digestive enzymes were incubated for 2 h and 4 h to simulate digestion in the stomach and the small intestine, respectively. The contents of CP, ether extract, neutral detergent fiber (NDF), and ash in the diets ranged from 14.4 to 42.5%, 3.5 to 23.5%, 6.4 to 34.6%, and 4.9 to 10.0%, respectively, on an as-is basis. The NDF contents were negatively correlated with the IVID of DM and CP (r = -0.73 and r = -0.62, respectively; p < 0.05). The most suitable prediction equations for the IVID of DM and CP in the dog diets were: IVID of DM (%) = 81.33 + 0.46 × CP - 0.77 × NDF, R2 = 0.78; IVID of CP (%) = 81.25 + 0.33 × CP - 0.49 × NDF, R2 = 0.64, where all nutrients were in % on an as-is basis. In conclusion, dry matter and protein utilization of dog diets based on in vitro digestibility assays can be estimated fairly well using protein and fiber concentrations as independent variables.

Effect of extrusion with molasses on the rumen undegradable protein fraction of canola oilcake meal and sweet lupins

The effect of the extrusion of canola oilcake meal (COM) and crushed sweet lupins (CSL) with molasses on the dry matter (DM) and crude protein (CP) degradability was determined in situ. Locally sourced (SOILL Moorreesburg, South Africa) COM and CSL, with the addition of 6% molasses, were extruded at a maximum temperature of 116 °C. A total of six Dohne Merino wethers (± 80 kg), fitted with rumen cannula, were used in this trial. Samples in polyester bags (5 g) were incubated in the rumen of the sheep at intervals of 0, 2, 4, 8, 16, 24, and 48 h. The DM and CP disappearances from the rumen were determined and degradability parameters were estimated. Extrusion increased the potentially degradable CP fraction by 43.5%. At each outflow rate, the average CP effective degradability of COM (68.2%) was lower than that of CSL (78.0%). Extrusion substantially lowered the CP effective degradability for both protein sources at every outflow rate tested. The biggest effect was seen at 0.08/h, where effective degradation was lowered by 25.6%. Extrusion with molasses was found to modify ruminal degradation parameters of both canola oilcake meal and crushed sweet lupins, while also decreasing the effective rumen degradation, especially at faster outflow rates. Thereby, the rumen undegradable protein fraction was increased by 85.4%. This study shows that COM and CSL extruded with 6% molasses can substantially increase RUP.

Study on the rumen fermentation, growth performance and carcass characteristics according to the supplementation of lupin flake in Hanwoo steers

This study was conducted to determine the rumen fermentation dynamics of lupin flakes and elucidate the effects of lupin flake supplementation on the growth performance, blood metabolites, and carcass characteristics of Hanwoo steers. In vitro and in situ trials of lupin grains and lupin flakes were conducted using three Hanwoo cows with rumen fistulas. The feeding trial included 40 early-fattening Hanwoo steers randomly divided into four groups: control, T1, T2, and T3. Their formula feed contained 0%, 3%, 6%, and 9% lupin flakes, respectively. In vitro rumen pH and ammonia concentrations were lower in the lupin flake group than in the lupin grain group after 6 and 24 h of incubation, respectively (p < 0.05). Concentrations of propionate, butyrate, and total volatile fatty acids were higher in the lupin flake group than in the lupin grain group after 12 h of incubation (p < 0.05), as was the crude protein disappearance rate at 9 and 12 h of rumen fermentation (p < 0.05). Supplementation with lupin flakes did not affect the average daily gain. Compared to that in the control group, dry matter intake was lower in the lupin flake-supplemented groups (p < 0.05); the feed conversion ratio was lower in T2 and T3 (p < 0.05); and plasma total protein concentration in 29-month-old steers was lower in T1 and T3 (p < 0.05). Plasma triglyceride concentration was lower in the lupin flake-supplemented groups than in the control group (p < 0.05). The incidence rate of yield grade A was higher in T1 and T2 than in the control group; the incidence rate of meat quality 1+ grade or higher was highest in T2. The carcass auction price was higher in T2 than in the other groups. Overall, compared to whole lupin grains, lupin flakes seem to more substantially affect rumen ammonia concentrations and crude protein disappearance rate. Additionally, we suggest that supplementation with 6% lupin flake formula feed exerts positive effects on the feed conversion ratio, yield grade, and quality grade of Hanwoo steers.

PSXIII-B-1 Black Soldier fly Larvae Were More Digestible Than Adult Flies, and Nutrient Disappearance in Black Soldier fly Larvae can be Predicted Using Acid Detergent Fiber Based on in Vitro Assays for Pigs

Abstract The objectives were to evaluate the nutrient utilization of fish meal, black soldier fly (BSF, Hermetia illucens) larvae, and adult BSF meal and to develop equations for estimating in vitro nutrient disappearance of BSF larvae for pigs. Two-step and 3-step in vitro procedures were used to simulate the digestion and absorption of nutrients in the gastrointestinal tract of pigs. In Exp. 1, defatted BSF larva meal had less (P &amp;lt; 0.05) in vitro ileal disappearance (IVID) of dry matter (DM; 81.2% vs. 91.6% and 61.6%) and crude protein (CP; 81.8% vs. 92.2% and 67.2%) and in vitro total tract disappearance (IVTTD) of DM (82.6% vs. 93.6% and 65.7%) and organic matter (OM; 78.1% vs. 91.5% and 63.2%) than fish meal and greater (P &amp;lt; 0.05) values than adult BSF. In Exp. 2, CP concentrations in BSF larvae were negatively correlated with ether extract (r = −0.91) but positively correlated with acid detergent fiber (ADF; r = 0.98) and chitin (r = 0.95). Acid detergent fiber and chitin concentrations in BSF larvae were negatively correlated with IVID of DM (r = −0.98 and −0.88) and CP (r = −0.87 and −0.84) and IVTTD of DM (r = −1.00 and −0.94) and OM (r = −0.99 and −0.98). Equations for in vitro nutrient disappearance of BSF larvae using ADF (% DM) as an independent variable were developed: IVID of CP, % = −0.95×ADF + 95 (r2 = 0.75 and P = 0.058) and IVTTD of OM, % = −2.60×ADF + 115 (r2 = 0.98 and P &amp;lt; 0.01). In conclusion, in vitro nutrient utilization of defatted BSF larva meal was less compared with fish meal but was greater compared with adult flies and in vitro nutrient utilization of BSF larvae can be predicted using ADF as an independent variable.

PSXV-18 Effects of Drying Methods for Black Soldier fly Larva Meals on in Vitro Nutrient Disappearance

Abstract The objective was to determine the effects of different drying methods on nutrient utilization of black soldier fly (BSF; Hermetia illucens) larva meals using in vitro assays. Two-step and 3-step in vitro assays were employed to simulate the gastrointestinal tract of pigs. Four methods were used to obtain BSF larva meal sources: 1) microwave-drying for 32 min, 2) hot-air drying at 60°C for 17 h, 3) water blanching for 5 min and hot-air drying for 17 h, and 4) 2% citric acid solution blanching for 5 min and hot-air drying for 17 h. After the drying process, each BSF larva was defatted and ground to obtain BSF larva meals. The crude protein (CP) concentration in the test ingredients ranged from 54.7 to 60.4% on dry matter (DM) basis and ether extract ranged from 7.1 to 11.8% DM. Hot-air-dried BSF larva meal had greater in vitro ileal disappearance (IVID) of CP compared with microwave-dried BSF larva meal (86.7% vs. 84.4%; P &amp;lt; 0.05). However, blanching BSF larva in water or 2% citric acid solution before hot-air drying resulted in less IVID of CP (81.3 or 82.5%; P &amp;lt; 0.05) compared with microwave-dried or hot-air-dried BSF larva meal. Blanching BSF larva in water or 2% citric acid solution before hot-air drying resulted in less in vitro total tract disappearance of DM (85.0% or 84.5% vs. 90.4% or 89.6%; SEM = 0.3, P &amp;lt; 0.05) and OM (80.6% or 81.5% vs. 85.7% or 86.6%; SEM = 0.1, P &amp;lt; 0.05) compared with microwave-dried or hot-air-dried BSF larva meal. In conclusion, hot-air-dried BSF larva meal had greater nutrient utilization compared with microwave-dried BSF larva meal. However, blanching BSF larva in water or citric acid solution negatively affected nutrient digestibility based on in vitro assays.

Comparative ileal digestibility of gross energy and amino acids in low and high tannin sorghum fed to growing pigs

Low tannin sorghum cultivars (LTS) have been previously proved to contain greater available energy and apparent total tract digestibility (ATTD) of gross energy (GE) and crude protein (CP) than high tannin sorghum cultivars (HTS); however, their comparative ileal digestibility of energy and nitrogen excluding microbial interference in pigs remains mostly unknown. This study was designed to compare apparent (AID) and standardized ileal digestibility (SID) of amino acids (AA) associated with the AID and hindgut disappearance (HGD) of GE and CP in 4 LTS and 4 HTS fed to growing pigs. Eighteen barrows (27.6 ± 3.5 kg) fitted with a distal ileum T-cannula were allotted to a replicated 9 × 3 Youden square design with 9 diets and 3 periods to give a total of 6 replicate pigs per diet. Each period lasted 10 days, with 5 days adaption to the diets followed by 3 days collection of faeces and then 2 days collection of ileal digesta. Eight sorghum diets contained 966 g/kg sorghum grain as the only source of dietary energy and nitrogen, and one nitrogen-free diet was used to determine basal ileal endogenous nitrogen loss. Mean AID, ATTD, and HGD of GE and CP were higher in LTS than in HTS (P < 0.05). Mean SID of 8 out of 15 AA were decreased in HTS (P < 0.05). The AID, ATTD, and HGD of GE or CP had a negative correlation with condensed tannins and total phenolics in sorghum grain (P < 0.05). The SID of essential AA, including lysine, threonine, valine, histidine, and arginine, were highly or moderately negatively correlated with condensed tannins and total phenolics content in sorghum grains (P < 0.05). Overall, HTS provided less ileal digestibility and hindgut disappearance of energy and nitrogen, implying that condensed tannins in sorghum grain may impede nutrient digestibility, not only in the foregut but also in the hindgut segements of pigs.

Ruminal disappearance of nutrients and ruminal phosphorus concentration in cows fed concentrates treated with lactic acid, with or without inorganic phosphorous supplementation

Our previous work indicates that lactic acid (LA) treatment of concentrates promotes ruminal fermentation output, and ruminal fungi benefit from LA treatment with inorganic phosphorous (iP) supplementation in dairy cows. In continuation of the previous study, the present work investigated whether treating concentrates with LA and iP supplementation would affect the ruminal release of nutrients of the treated concentrates as well as the fibre degradation in the rumen. Three dietary treatments were tested in a Latin square trial with 6 rumen cannulated dry Holstein cows. Diets were a control diet, without LA treatment, supplemented with iP (CON+iP), and two LA-treated diets: one with (LA+iP) and another without inorganic P supplementation (LA-iP). Monocalcium phosphate and a conventional vitamin-mineral premix were supplemented in CON+iP and LA+iP diets, while LA-iP contained no iP source. All diets were offered as a total mixed ration (forage to concentrate ratio of 53:47 on dry matter (DM) basis) and contained total P levels of 4.1 g/kg DM for LA-iP and 4.7 g/kg DM for both iP supplemented diets. The in situ ruminal disappearance of nutrients in the respective concentrate mixtures and the hay incubated as substrates, as well as the P concentrations of the free ruminal liquid and solid rumen digesta were studied. Data showed that LA-treatment increased the solubility and thus sped up ruminal disappearance as well as increased the effective rumen disappearance of ash, P and crude protein of the concentrates, independent of iP supplementation. The overall in situ disappearance of starch was similar amongst all treatments. The in situ disappearance of nutrients of the hay was minimally affected by LA treatment and the iP supplementation. The ruminal P concentrations were least in LA-iP compared to CON+iP and LA+iP. In conclusion, LA treatment improves ruminal degradation of the treated concentrates, especially P, other minerals and crude protein. With the current total dietary P levels fed, neither LA treatment nor iP supplementation affects the overall ruminal fibre degradation.

Ruminal degradability of bypass fat and protein of certain commonly used feedstuffs in dairy rations

Studies were conducted to determine the rumen degradability of protein of certain commonly used feed ingredients and degradability of bypass fat used in dairy rations. In situ crude protein (CP) disappearance of groundnut cake, soybean extraction, cottonseed cake, maize gluten meal, wheat bran, rice bran, maize, 0.3, 0.6 and 0.9% (of CP) formaldehyde treated soybean extraction, and in situ fat disappearance of bypass fat in the rumen at different incubation periods were determined by nylon bag technique using 3 adult crossbred steers. The effective degradability was calculated for an assumed outflow rate of 5%/h. The effective CP degradability of groundnut cake, soybean extraction, cottonseed cake, maize gluten meal, wheat bran, rice bran, maize, 0.3, 0.6 and 0. 9% (ofCP) formaldehyde treated soybean extraction was 86, 74, 66, 21, 73, 65, 63, 66, 48 and 26%, respectively. The effective fat degradability of bypass fat was 86%. The results indicated that maize gluten meal is a good source of bypass protein. Soybean extraction although extensively degraded in the rumen, contribute fairly more amount of undegradable protein than rumen degradable protein at an outflow rate of 5%/h, when it is treated with 0.6 and 0.9% (of CP) formaldehyde. The bypass fat supplement prepared from rice bran acid oil is a good source of energy in which about 86% of fat would be available at the lower tract of ruminants. Therefore, maize gluten meal, 0.9% formaldehyde treated soybean extraction and protected fat can be included in the rations of dairy animals forimproved productive performance

Effects of calcium salt of linseed oil fatty acid with different oil adsorbents on in vitro gas production and ruminal fermentation characteristics.

We investigated the effects of supplementary calcium salt of fatty acid (CSFA) from linseed oil with different oil adsorbents on in vitro gas production and rumen fermentation characteristics in barley substrate condition. A non-supplementation treatment (CONT) and treatments of six products, CSFA without oil adsorbent (2.1 fatty acid/Ca molar ratio) and CSFAs with silica gel, zeolite, bentonite, diatomite, and vermiculite (2.8 fatty acid/Ca molar ratio), were prepared. The supplementary 2% and 4% CSFA with silica gel (+S) in the substrate reduced CH4 production 56% and 79%, respectively, compared with that in CONT (p < 0.01). The products, except for +S, did not decrease CH4 production. The dry matter (DM) disappearance in CSFAs with oil adsorbents was lower than that in the CSFA without oil adsorbent (74.8%-77.3% vs. 79.3%, p < 0.01), and crude protein (CP) disappearance in +S supplementation was lower than that of the other products (53.5% vs. 57.2%-59.1%, p < 0.01). The +S supplementation decreased acetate proportion and increased propionate proportion (p < 0.01). Our study indicated that although the disappearance of DM and CP might decrease, using silica gel as an oil adsorbent of linseed oil calcium salt with high fatty acid/Ca molar ratio has the potential to mitigate CH4 emissions from ruminants.

Nutritive value of mixed napier grass (Pennisetum purpureum)- Leucaena (Leucaena leucocephala) silage for ruminants

The objectives of the study were to determine the chemical composition, ruminal degradability, and apparent digestibility of mixed Napier (Pennisetum purpureum) (PP) -Leucaena (Leucaena leucocephala) (LL) silages. Freshly cut Napier and Leucaena were harvested and mixed at 70:30; 50:50; 30:70 ensiled for six weeks. The chemical composition of the fresh forages and the silages were determined using the AOAC (1990) procedures. Dry matter (DM) and crude protein (CP) ruminal degradability were determined by nylon bag technique using three rumen cannulated Bonsmara steers for periods of 0, 6, 12, 24, 48, 72, 96 and 120 hours. DM and CP ruminal degradability kinetics were described by fitting the data on the model P= a+b (1-e−ct) using the neway computer program where a is the rapidly degradable fraction, b is the slowly degradable fraction and c is the outflow rate. Hay supplemented with 25% mixed PP: LL silages was fed to three castrated male Pedi sheep to evaluate apparent digestibility coefficient and N retention. The fresh cut PP had more CP, Fat, and ash, with less OM. Leucaena was richer in most nutrients than Napier. The study indicated the 50:50 silage was the optimal mix to maximize the overall nutritive value. The DM and CP disappearance constants a, b and c were similar for all silages. PP: LL mixing ratio did not affect the DM and CP degradability kinetics of the silages. There was no effect on total dietary intake, apparent digestibility and N retention.

Determining the effect of natural inhibitors on sesame meal degradability using in vitro three step method

The aim of this experiment was to investigate the beneficial effect of monensin, tannic acid and cinnamon essential oil addition on sesame meal degradability by the three-step in vitro method. The effect of experimental additives on the degradability of sesame meal in the rumen, after rumen and in the whole gastrointestinal tract was significant (P&lt;0.05). The in vitro ruminal and intestinal digestibility of sesame meal crude protein with experimental additives was in the range of 76 to 84% and 49 to 60%, respectively. The intestinal degradability of crude protein increased with the addition of cinnamon essential oil (about 10%). Addition of monensin, tannic acid, and cinnamon essential oil significantly increased the degradability of Neutral Detergent Fiber (NDF) and Acid Detergent Fiber (ADF) in the rumen, intestines and the whole gastrointestinal tract. The results showed that cinnamon essential oil (125 mg/L) increased the degradability of dry matter (DM), organic matter (OM), crude protein (CP), ADF and NDF in the rumen, after rumen and the whole digestive tract compared to all treatments (P&lt;0.05). The results showed that addition of tannic acid (100 mg/L) decreased the disappearance of crude protein in the rumen, while it increased crude protein’s disappearance in the after rumen (P&lt;0.05).

In situ ruminal disappearance of crude protein and phytate from differently processed rapeseed meals in dairy cows.

The influence of different processing conditions of rapeseed meal on ruminal degradation of crude protein and phytate in dairy cows was investigated. Following oil extraction from the rapeseed, five residence times in the desolventizer/toaster were chosen to remove the solvent from the meal. Rapeseed cake and rapeseed meals were incubated in situ in the rumen of three fistulated dairy cows to determine ruminal degradation parameters. With increasing residence time in the desolventizer/toaster the ruminal degradation of crude protein decreased significantly for every treatment step. Ruminal phytate degradation and crude protein degradation were affected almost identically. The processing conditions of rapeseed meal have a major impact on the ruminal degradation of crude protein and phytate, indicating a potential conflict of interest regarding the production process. Large amounts of undegradable rumen protein are often intended for high-yielding dairy cows whereas a high level of ruminal degradation is preferred for phytate to increase absorption of phosphorus in the small intestine. © 2021 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.