Effects of heat treatment on the nutritional value of raw soybean selected for low trypsin inhibitor activity

1. Two broiler experimentss and a layer experiments were conducted on Kunitz trypsin inhibitor (Kti) soybeans (SB) of low trypsin inhibitor (TI) activity to determine their nutritive value when included as mash in least-cost poultry diets. 2. Experiment 1 compared chick performance on the Kti or raw SB using a commercial full-fat SB meal (FFSBM) and a solvent extracted SB meal (SBM) as controls during a 20 d experimental period. Broiler experiment 2 compared Kti and raw SB, non-steamed, or steam-pelleted with and without DL-methionine supplementation added to every treatment containing 170 g SB/kg. For each broiler experiment the levels of each SB were 70, 120 and 170 g/kg with the control birds fed only 170 g SB/kg. 3. The layer experiment, compared steam-pelleted Kti and raw SB against a non-steamed Kti and raw SB each fed at two levels (70 and 110 g/kg) x 30 replicates from 29 weeks of age for 19 weeks in a completely randomised design. Production parameters were measured when diets were formulated to contain minimum required specifications and calculated apparent metabolisable energy (AME). At the completion of each trial, 2 broiler birds from each cage and 5 layer birds per treatment were killed, weighed, and their liver and pancreas weighed. 4. Both broiler experiments indicated that production parameters on the Kti SB treatments were significantly lower (P<0.05) than on the two commercial control SB treatments. However, the Kti treatments were superior to the raw SB treatments. 5. Pancreas weight increased with increasing inclusion of both raw and Kti SB, suggesting that a TI was causing the depression in performance. The AME of the Kti SB was similar to that of commercial FFSB meal. After steam conditioning, the raw SB meal AME value of 9.5 MJ/kg dry matter (DM) was improved to 14.1 MJ/kg DM by reduced TI activity, but this AME improvement with TI activity reduction, plus the supplementation with DL-methionine on birds fed the raw SB had no effect (P>0.05) on any parameter evaluated in experiment 2. 6. The layer experiment showed that hens on the Kti SB treatments had significantly greater live weight gain (LWG), egg weight and daily egg mass than birds given raw SB. A reduced food intake (FI) was observed in the Kti treatments but egg mass was generally similar to that on the FFSB control diet, indicating that Kti SB supported excellent egg production at an inclusion of 110 g/kg. The depressed performance observed for broiler chicks suggest that younger birds are more susceptible to the effects of SB TI.     

Nutritional evaluation of high-digestible sorghum for pigs and broiler chicks

Two experiments were conducted to evaluate the nutritional quality of 2 varieties of Purdue high-digestible sorghum (PHD1 and PHD2) and a normal sorghum, compared with corn, in diets of pigs and broiler chicks. In Exp. 1, 12 pigs (average BW, 55 kg) fitted with ileal T-cannula were fed 4 diets containing 946 g of corn or sorghum (PHD1, PHD2, and normal) per kg in a 2-period crossover design (i.e., each pig received 2 diets over a 2-wk period with 6 pigs per dietary treatment) to determine apparent ileal or total tract digestibility of nutrients and energy. There was no difference in the ileal or total tract digestibility of DM, energy, P, Ca, or N among dietary treatments. In Exp. 2, a total of 192 broiler chicks were grouped by weight into 8 blocks of 4 cages each with 6 chicks per cage, and cages were assigned randomly to 1 of the 4 dietary treatments within each block. Chicks were fed corn-soybean meal (SBM) or sorghum-SBM diets for 21 d to determine apparent total tract retention and then switched to diets containing 935 g of the corresponding corn or 1 of the 3 sorghum varieties per kg for 7 d to determine apparent ileal digestibility and total tract retention. Apparent ileal digestibilities of DM and P, as well as energy, were not different in chicks fed diets containing 935 g of corn or 1 of the 3 sorghum varieties per kg. However, apparent total tract retention of DM, energy, and N in chicks fed corn was greater (P < 0.05) than those fed 1 of the 3 sorghum varieties. Although the apparent ME content of corn was greater than PHD1 and normal sorghum (P < 0.01), it was not different from PHD2 sorghum. There was no difference in apparent total tract retention of DM between chicks fed the corn-SBM and PHD-SBM diets, but it was greater (P < 0.05) in chicks fed the corn-SBM diet than those fed the normal sorghum-SBM diet. Apparent total tract retention of N in chicks fed the PHD1-SBM diet was lower (P < 0.05) than in those fed the corn-SBM diet but greater (P < 0.05) than in chicks fed the normal sorghum-SBM meal diet. No difference in the apparent ME content between the corn-SBM and PHD2-SBM diets was observed, but it was greater (P < 0.05) for the corn-SBM diet than the PHD1- or normal sorghum-SBM diet. Weight gain, feed intake, and feed efficiency were not different in chicks fed the corn-SBM or sorghum-SBM diets. Sorghum could serve as a substitute for corn in cereal grain-SBM diets for pigs and broiler chicks.     

Evaluation of xylanase and a fermentable xylo-oligosaccharide on performance and ileal digestibility of broiler chickens fed energy and amino acid deficient diets

The objective of this study was to evaluate the effect of a product consisting of a combination of xylanase and xylo-oligosaccharide (STBIO) on performance and ileal digestibility of broiler chickens fed energy and amino acid (AA) deficient diets. Day-old male Ross 308 broiler chicks were randomly allocated to 8 pens per treatment, with 25 chicks per pen. Treatments based on wheat-corn-soybean meal diets were arranged in a 3 × 2 factorial design: a positive control that met or exceeded nutrient recommendations (PC), a negative control diet with a 50 kcal/kg apparent metabolizable energy (AME) reduction (NC1) and NC1 with a 3% reduction in AA content (NC2), each with or without supplementation of 100 g/t of the STBIO. Body weight gain (BWG), feed intake, feed conversion ratio corrected for mortality (FCR) and the European production efficiency factor (EPEF) were recorded from 0 to 42 d. On d 42, ileal samples were collected to determine dry matter (DM), organic matter (OM), ash, protein and energy digestibility. A significant interaction was observed for BWG and feed intake (P < 0.001). The energy and AA reduction reduced (P < 0.05) BWG when compared to the PC. The effect of STBIO on BWG was greater in NC1 (+451 g/bird) than in NC2 (+314 g/bird) or PC (+176 g/bird) diets (P < 0.05), and that in NC2 with STBIO was equal to that in PC without STBIO, and that in NC1 with STBIO was equal to that in PC with STBIO. No interactions were observed on the EPEF or FCR; however, STBIO improved EPEF (P < 0.001) and FCR (P < 0.001) irrespective of the energy reduction or AA density. The intake of digestible DM, OM, ash and energy for the finisher period was increased with STBIO supplementation (P < 0.01). A significant interaction was observed for the intake of digestible protein. NC1 and NC2 reduced the intake of digestible protein; however, when STBIO was supplemented, it was improved in both diets to similar levels to the PC. The stimbiotic supplementation improved performance of broiler chickens fed all diets, particularly those deficient in AME and AA.     

Dietary lysine and threonine requirements of the pregnant sow estimated by nitrogen balance

Two experiments were conducted to determine the lysine and threonine requirements of gestating sows. In the first experiment, four levels of lysine (0.34,0.42,0.48, and 0.56% crude lysine, and 0.24,0.31, 0.38, and 0.45% standardized ileal digestible lysine) were compared in eight multiparous Large White sows. Each sow received successively the four diets according to a Latin-square experimental design. Nitrogen balance was measured over 11 d after a 10-d period of adaptation to the experimental diet. In the second experiment, four threonine/lysine ratios (0.63, 0.73, 0.80, and 0.89 on a crude basis and 0.61, 0.71, 0.77, and 0.87 on a standardized ileal digestible amino acid basis) were compared in 16 multiparous sows, according to a Latin-square experimental design. The standardized ileal digestibility of amino acids in the experimental diets was determined with ileo-rectal anastomized growing pigs. In the first experiment, nitrogen retention was affected by lysine supply (linear, P < 0.001; quadratic, P < 0.04). Nitrogen retention was lowest for treatment 1 (8.0 g/ d) and highest for treatments 3 and 4 that did not differ. Nitrogen retention plateaued at 14.7 g/d in sows consuming 10.5 g/d of digestible lysine. The maintenance requirement for digestible lysine was calculated to be 27 mg/kg BW(0.75) with an efficiency of utilization of digestible lysine above maintenance at 59%. In the second experiment, nitrogen retention was affected (P < 0.03) by the threonine:lysine ratio. It was lower for the lowest threonine:lysine ratio (0.63) than for the other three treatments that did not differ among each other. These results indicate that the optimal standardized digestible threonine:lysine ratio appears to be about 0.71 for multiparous gestating sows.     

不同温度膨化全脂大豆对仔猪氮平衡和氨基酸消化率的影响

本试验目的在于检测不同温度下蒸汽膨化的全脂大豆对仔猪氮平衡和氨基酸消化率的影响。2个氮平衡试验共用24头杂交去势公猪,平均体重5.1公斤,21日龄断奶时,在小肠末端手术安装T—形瘘管。所用基础日粮含1.25％赖氨酸,10％豆油。10％葡萄糖和浸提豆粕,利用经110℃、130℃和150℃蒸汽膨化处理的三种全脂大豆,以等氮和等赖氨酸来替代基础日粮中的豆粕,用玉米淀粉补足日粮的百分比。代谢试验室内安有自动控温和通风设备。每个氮平衡试验收集粪尿和食糜样本2期。结果表明,仔猪采食含有在130℃下膨化的全脂大豆日粮后,氮消化率高于(p<0.05)在110℃下膨化的全脂大豆。而经150℃膨化处理的大豆,氮存留量,氮消化率,氮存留量没有进一步的改善,经130℃膨化的全脂大豆其赖氨酸、蛋氨酸和异亮氨酸的回肠表观消化率,高于(p<0.05)经110℃和150℃处理的大豆。但是,苏氨酸、缬氨酸和亮氨酸的回肠末端表观消化率随膨化温度的升高而增加。本试验表明,全脂大豆经130℃蒸汽膨化处理有利于改善仔猪对大豆中赖氨酸、蛋氨酸和异亮氨酸的回肠表观消化率,可以改善氮沉积量和氮存留率,但与优质豆粕相比,效率不显著。     

Apparent ileal digestibility of amino acids and the digestible and metabolizable energy content of dry extruded-expelled soybean meal and its effects on growth performance of pigs

We conducted three experiments to determine the apparent ileal digestibility of amino acids (Exp. 1), metabolizable and digestible energy (Exp. 2), and feeding value (Exp. 3) of dry extruded-expelled soybean meal with (DEH) or without (DENH) hulls compared with solvent-extracted soybean meal with hulls removed (SBMNH). Soybeans used to produce DEH were unadulterated prior to extrusion, but those used for DENH were dehulled prior to extrusion. In Exp. 1, six nonlittermate barrows (initially 39 kg) were fitted with ileal T-cannulas and used in a replicated 3 x 3 Latin square design digestion trial. Experimental diets (0.80% total lysine) were cornstarch-based and contained soybean meal from one of the three different sources as the sole source of lysine. Apparent ileal digestibilies of nutrients were similar (P > 0.10) for DEH and DENH. Apparent ileal digestibilies of CP, Lys, Ile, Leu, Arg, Phe, and Val were greater (P < 0.05) for DEH and DENH than for SBMNH. In Exp. 2, six barrows (initially 41 kg) were fed three corn-based diets containing 25% of one of the three soybean meal sources. A fourth diet was fed at the end of the trial containing all ingredients except soybean meal, so that energy values of the soybean meal could be determined by difference. Digestible energy and ME contents were similar (P > 0.10) for DEH and DENH and both had greater (P < 0.05) DE and ME contents than SBMNH. In Exp. 3, pigs (n = 216, initially 10.6 +/- 1.3 kg and 35 +/- 3 d of age) were blocked by weight and allotted to six dietary treatments. Corn-soybean meal-based diets (0.95% digestible lysine and 3.44 kcal/g ME) containing DEH or DENH were compared with similar diets containing SBMNH or solvent-extracted soybean meal with hulls (SBMH). In addition, a diet containing a second expelled soybean meal with hulls (ESBM) was compared with a diet containing SBMH and soy oil. Growth performance of pigs fed diets containing DEH or DENH was not different (P > 0.10) than that of pigs fed corresponding diets containing SMBH or SBMNH. Pigs fed ESBM had lower (P < 0.05) ADG and G/F compared with its corresponding SBMH and soy oil diet. In conclusion, DEH and DENH are more digestible than conventional soybean meal and can be successfully used in swine diets.     

The response of broiler breeder hens to dietary lysine and methionine.

1. Broiler breeder hens were used in an experiment lasting 10 weeks (29 to 38 weeks of age) to measure the responses to dietary lysine and methionine, the main objective being to determine whether the coefficients of response to these amino acids were the same for broiler breeders and for laying pullets. 2. The hens were offered 150 g/d of one of 20 dietary treatments, 10 being lysine-limiting and 10 being methionine-limiting. The diets were mixed by diluting one of two concentrate (summit) mixes with a protein-free dilution mixture. The lysine-limiting summit diet was designed to supply approximately 1300 mg lysine/bird d, while the other supplied 520 mg methionine/bird d, when fed at 150 g/bird d. 3. Birds on the 5 lowest concentrations of both lysine and methionine did not consume the allotted amount of food, the amount decreasing, in a curvilinear fashion, to approximately 105 g/bird d. 4. The minimum egg weight recorded was 0.8 of the maximum, whereas the rate of lay of birds fed on the diets with the lowest amino acid concentrations was 0.2 of the maximum. 5. Using the Reading Model, the coefficients of response were calculated to be (for lysine) 16.88 E and 11.2 W, and for methionine, 7.03 E and 1.52 W, where E = egg output, g/bird d, and W = body mass, kg/bird. An average, individual, broiler breeder of 3 kg, producing 45 g of egg output per day, would need 793 mg of lysine and 321 mg of methionine daily. This intake of methionine is similar to that estimated by means of coefficients used for laying pullets, but the lysine requirement would be underestimated by 0.18 if the coefficients for laying pullets were used. 6. The coefficients for maintenance for both lysine and methionine, determined in this experiment, are considerably lower than values published previously, whilst the coefficients for egg output are, in both cases, higher. The resultant flock response curves therefore differed significantly from those in which the coefficients of response for for laying pullets were used.(ABSTRACT TRUNCATED AT 400 WORDS)     

Sensitivity of broiler starters to three doses of an enzyme cocktail in maize-based diets

1. The aim of the present study was to investigate the effect of an enzyme cocktail composed of xylanase, amylase and protease on the performance and nutrient utilisation of broiler starters fed on a maize-based diet. A maize/soy-based control diet was formulated to be marginal in apparent metabolisable energy (AME) and amino acids and this diet was fed without or with two concentrations (250 and 500 g/tonne) of the exogenous enzyme cocktail. 2. Growth performance was measured over a 21-d period after which ileal contents were collected for measurement of digestible energy, nitrogen and dry matter. Excreta were collected from d 17 to 20 post-hatch and used to determine the AME, and retention of nitrogen and dry matter. 3. Supplementation of the control diet with 250 and 500 g/tonne of the enzyme cocktail resulted in enhanced performance of the chicks (1.4 and 8.3%, respectively, for weight gain and 1.2 and 2.2%, respectively, for feed per gain), but the improvements were significant (P < 0.05) only at 500 g/tonne. 4. Addition of both 250 and 500 g/tonne improved AME, nitrogen-corrected AME and dry matter retention compared with the control though the improvements were greater with the higher dose. These effects were also reflected in the apparent ileal digestibility coefficients of dry matter, nitrogen and energy, with 500 g/tonne of the enzyme cocktail improving ileal digestible energy by 3.4%. 5. These results demonstrate that a cocktail of exogenous enzymes containing xylanase, amylase and protease is effective in improving the performance of broiler chicks fed on a maize/soybean-meal-based diet. However, these benefits may be dose-dependent and so an economic analysis involving ingredient and enzyme pricing and the relative performance and digestibility enhancements could allow the end user to select the most economical dose to maximise return on investment.     

Influence of bird strain on competitive exclusion of Campylobacter jejuni in young chicks

1. Newly hatched chicks of either layer or broiler strain were treated orally at regular intervals with either homologous or heterologous gut-flora preparations from young donor birds, in an attempt to prevent subsequent colonisation with Campylobacter jejuni by 'competitive exclusion' (CE). 2. Donors of 3 to 10 d of age were chosen to correspond with the period in which intensively reared poultry are least likely to become colonised with Campylobacter. 3. In two separate trials, material from donor layer hens (ISA Brown) protected male chicks of the same strain against a low (195 to 360 cfu/bird) Campylobacter challenge, but the same kind of material was ineffective when administered to chicks of a broiler strain (JA957). 4. Two further trials involved treatment preparations from young broilers, which failed to prevent Campylobacter colonisation of broiler chicks, even when colonisation occurred relatively slowly from a challenge of 90 to 94 cfu/bird. 5. It was concluded that any CE effect observed was strongly dependent on bird strain.     

Effect of food enzymes on AME and composition of digesta from broiler chickens fed on diets containing non-starch polysaccharides isolated from lupin kernel

1. The effects of lupin non-starch polysaccharides (NSPs) on apparent metabolisable energy (AME) and composition of digesta from broiler chickens were examined in a dose-response experiment in conjunction with a single combination of 2 commercial enzyme products known from previous studies to partially depolymerise NSPs in diets containing sorghum, casein and lupin kernel. The 7-d experiment was conducted on broiler chickens (24 to 31 d of age) in metabolism cages. 2. The basal diet used in this study contained (in g/kg) sorghum (low tannin) 800, casein 134, celite 20 and vitamins and minerals 46. The inclusion rate for each enzyme product was 0.2 g/kg. Lupin kernel isolate (containing 560 g/kg total NSPs) replaced some of the sorghum and casein. The dose rates of lupin kernel isolate (50, 100 and 150 g/kg) were equivalent to dietary inclusion rates of 80, 160 and 240 g/kg, approximately, of untreated lupin kernel from Lupinus angustifolius cultivar Gungurru. 3. Inclusion of lupin kernel isolate in the diet depressed AME and bird performance, and raised ileal viscosity and excreta moisture, in a dose-dependent manner. 4. A combination of 2 proprietary enzyme products improved dietary AME by 0.3 MJ/kg dry matter. Enzymes reduced excreta moisture when inclusion of lupin kernel isolate was 50 g/kg (equivalent to lupin kernel at 80 g/kg, approximately) but not at higher inclusions. 5. Food enzymes partially depolymerised some insoluble NSPs in lupin kernel isolate, which increased ileal viscosity and soluble NSP content of digesta. 6. It was concluded that development of appropriate exogenous enzyme products could lead to lupin NSPs being used as an energy source for poultry.     

Increasing dietary pectin level reduces utilization of digestible threonine intake, but not lysine intake, for body protein deposition in growing pigs

Two N balance studies were conducted to investigate the effects of feeding graded levels of pectin (a soluble nonstarch polysaccharide, NSP) on the utilization of ileal digestible threonine (Thr; Thr study) and lysine (Lys; Lys study) intake for body protein deposition (PD) in growing pigs. In each study, eight Yorkshire barrows with an average initial BW of 17.2 +/- 1.3 (Thr study) and 14.3 +/- 1.4 kg (Lys study) were fed each of five experimental diets during five subsequent experimental periods, according to a crossover design. Pigs were fed twice daily at 2.6 times maintenance energy requirements. The soybean- and cornstarch-based diets, in which either Thr or Lys was the first-limiting nutrient, were formulated to contain (as-fed basis) 0, 4, 8, or 12% pectin or 8% cellulose (water-insoluble NSP), respectively, and with NSP substituting cornstarch. Across treatments, the mean daily Thr and Lys intake were 5.42 +/- 0.04 g/d (Thr study) and 7.98 +/- 0.12 g/d (Lys study), respectively. Apparent and standardized ileal digestibilities of Thr and Lys were determined in a separate study. Mean PD was 93.4, 90.2, 82.1, 76.7, and 87.9 g/d (SEM = 1.3; Thr study) and 90.7, 88.6, 87.8, 85.3, and 88.1 g/d (SEM = 1.1; Lys study) for the five respective treatments. Utilization of ileal digestible Thr intake, but not of ileal digestible Lys intake, for PD decreased linearly with dietary pectin level, and was not influenced by diet cellulose level. The current study indicates that apparent and standardized ileal digestibility values do not provide an accurate predictor of dietary effects on the utilization of ileal digestible Thr intake for protein deposition in growing pigs fed diets containing soluble NSP.     

Dietary cholecalciferol and phosphorus influence intestinal mucosa phytase activity in broiler chicks

1. The role of cholecalciferol and phosphorus in the regulation of intestinal mucosa phytase was investigated in broiler chicks. 2. A total of 144 7-d-old male broiler chicks were grouped by weight into 6 blocks of 4 cages with 6 broiler chicks per cage. Four maize-soybean meal-based mash diets were randomly assigned to cages within each block. The 4 diets consisted of cholecalciferol at 0 or 75 microg/kg and total phosphorus at 3.6 or 7.0 g/kg in a 2 x 2 factorial arrangement. The birds were given the experimental diets for 12 d under conditions which excluded ultraviolet light. 3. Broiler chicks fed on diets with the higher concentration of cholecalciferol had higher Vmax and Km of the mucosa phytase, weight gain, feed intake, feed efficiency and percentage tibia ash, higher ileal digestibility of dry matter, energy, phosphorus (P) and calcium (Ca), and increased retention of dry matter, nitrogen, P, Ca and energy. 4. Broiler chicks receiving diets with the higher P concentration showed lower Vmax and Km of the intestinal mucosa phytase but greater weight gain, feed intake, feed efficiency and percentage tibia ash, higher ileal digestibility of dry matter, energy, P and nitrogen, and increased retention of dry matter, energy, nitrogen and Ca. 5. In conclusion, both dietary P and cholecalciferol influenced the activity of intestinal mucosa phytase.     

Performance and meat quality of broiler chickens that are fed diets supplemented with Agaricus brasiliensis mushrooms

This trial was performed to study the use of the mushroom Agaricus brasiliensis as an alternative additive to antimicrobial growth promoters in broiler chicken diets and to assess the quality of the broiler chicken breast meat of birds that are fed diets containing this fungus. Thus, 595 1-day-old chicks were reared in reused poultry litter without anticoccidial and antimicrobial additives. The results showed that a concentration of 1.6 g mushrooms/kg diet was ideal for these birds because it provided better bird performance. When the birds’ immune system organs were analyzed, it was found that the addition of both mushrooms influenced the immune system organs of these broiler chickens. Adding A. brasiliensis to broiler chicken diets did not compromise breast meat quality.     

Influence of pre‐press solvent‐extracted cottonseed meal supplemented with exogenous enzyme and digestible lysine on performance,digestibility, carcass and immunity responses of broiler chickens

The response of broiler chickens to two levels of endo‐1,4‐β xylanase (EC 3.2.1.8) and endo‐1,3‐β glucanase (EC 3.2.1.6) combination (with and without), three levels of digestible lysine (0.8%, 0.9% and 1.0% with the applicability of ideal protein concept) and two levels of cottonseed meal (CSM; 20% and 30%) were evaluated in 2 × 3 × 2 factorial arrangement. A total of 2448 male Hubbard broiler chicks were fed on practical vegetable‐based mash diets having 2750 kcal metabolizable energy (ME) per kg and 18.5% crude protein (CP) from the age of day 1 to 42. The supplemental enzyme had minimum 1100 units of endo‐1,4‐β xylanase and 100 units of endo‐1,3‐β glucanase/kg of finished diet. The addition of CSM at 30% resulted in increasing arginine to lysine ratio. A decrease in dressing and breast percentages were observed by the addition of 30% CSM. The digestible lysine at 1.0% decreased the body weight (BW) gain and lowered the mortality during day 1 to 21 whereas the BW gain and feed:gain ratio were unaffected among the three digestible lysine levels during day 1 to 42. The antibody titres against Newcastle and infectious bursal disease viruses were improved with the increasing levels of digestible lysine. The enzyme supplementation improved the apparent ME and digestibility coefficient of nitrogen when it was used with 30% CSM. No effect of enzyme, lysine, CSM or their interactions was observed on serum iron, gizzard and liver weights or abdominal fat percentage. The results showed that increasing digestible lysine improved the antibody titre but did not improve the growth performance and carcass characteristics; supplemental enzyme failed to show any improvement in performance of birds fed on CSM‐based diets.     

Nutritional value of a genetically improved high-lysine, high-oil corn for young pigs

Two experiments were conducted to compare the nutritional adequacy of a genetically improved high-lysine, high-oil corn (HLHOC; .408% lysine, 6.21% fat, as-fed basis) and a high-oil corn (HOC; .289% lysine, 5.97% fat, as-fed basis) for young growing pigs. Experiment 1 used four non-littermate barrows (initially 20.0 kg BW) fitted with ileal T-cannulas in a crossover-designed digestion study. The .75% total lysine diets contained 8.5% casein and an equal amount of lysine (.25%) from the test corn. Apparent ileal digestibilities of amino acids, GE, DM, and CP were similar (P > .10) between diets. Apparent ileal lysine digestibilities were 65 and 71% for the HOC and HLHOC, respectively, assuming the lysine in casein to be 100% digestible. Experiment 2 used 100 barrows reared in a segregated early-weaning environment (initially 8.3 kg BW and 27 d of age) to evaluate five corn-soybean meal-based diets in a 2 x 2 factorial arrangement with main effects being corn type and dietary lysine (.80 or 1.15% digestible lysine). The fifth diet consisted of the .80% digestible lysine HOC diet supplemented with .23% additional L-lysine x HCl (.975% digestible lysine) to verify that lysine was the limiting amino acid in the low-lysine diets. Increasing digestible lysine from .80 to 1.15% increased (P < .001) ADG and gain/feed (G/F) regardless of corn variety. Combined ADG and G/F were .347 kg and .641 and .443 kg and .790 for the .80 and 1.15% digestible lysine diets, respectively. Within lysine level, corn type did not affect ADG, ADFI, or G/F (P > .10). The results of these studies indicate that the lysine in HLHOC is as available as the lysine in HOC and that HLHOC can be used successfully in swine diets.     

Relative ileal amino acid flows and microbial counts in intestinal effluents of Goettingen Minipigs and Saddleback pigs are not different

We explored the suitability of Goettingen Minipigs as models to measure ileal AA digestibility and evaluate dietary proteins for conventional pigs. Further, a potential for secondary ileal microbial colonization 5 mo after establishing end-to-end ileorectal anastomosis was investigated. Goettingen Minipigs (BW 18 kg) and Saddleback pigs (BW 27 kg) fitted with end-to-end ileorectal anastomosis were fed six diets based on barley and oilseed meals and three diets based on wheat and milk powder differing in total and ileal digestible lysine. Apparent ileal digestibilities of CP (N x 6.25) and of 20 AA were determined. No differences (P = 0.062 to 0.982) were found in AA apparent ileal digestibilities between breeds. Therefore, Minipigs are a reasonable model to estimate apparent ileal digestibility of AA for evaluation of dietary proteins. However, the apparent ileal digestibility of CP (P = 0.048) was higher in Minipigs than in Saddleback pigs (barley and oilseed meals-based diets 70% vs. 66%; wheat and milk powder-based diets 80% vs. 77%), which is probably due to a smaller contribution of non-AA-nitrogen in the ileal effluent of Goettingen Minipigs. For lysine, the apparent ileal digestibilities (means of both breeds) ranged from 78 to 85% in wheat and milk powder-based, and 70 to 78% in barley and oilseed-based diets. Experimentally derived concentrations of ileally digestible lysine confirmed the values predicted from a published table. Microbial counts were not affected by breed as shown for lactobacilli, with 9.1+/-0.2 and 9.1+/-0.2 (P = 0.977), enterococci with 4.8+/-0.3 and 5.6+/-0.4 (P = 0.162), and yeasts with 4.6+/-0.3 and 4.6+/-0.4 (P = 0.906) log cfu/g effluent for Goettingen Minipigs and Saddleback pigs, respectively. The counts did not change over 5 mo, suggesting that no secondary microbial colonization occurred in pigs with end-to-end ileorectal anastomosis.     

Early growth and environmental implications of dietary zinc and copper concentrations and sources of broiler chicks

1. Environmental accumulation of zinc and copper is becoming a concern in areas having intensive animal production. This study examined performance and excretion of broiler chicks given diets supplemented with graded concentrations of zinc and copper from three different sources. 2. Two experiments were conducted, each utilising 570 1-d-old chicks. In Experiment 1, chicks were given diets containing supplemental zinc concentrations from 40 to 120 mg/kg supplied as zinc sulphate, a zinc amino acid complex (Availa Zn), or a combination of zinc sulphate and Availa Zn with each contributing one-half of the total supplemental zinc. In Experiment 2, broiler chicks were given diets with graded concentrations of supplemental copper ranging from 4 to 12 mg/kg from copper sulphate, a copper amino acid complex (Availa Cu), or a combination of copper sulphate and Availa Cu with each contributing one-half of the total supplemental copper. 3. During the 17-d experimental period, mineral concentration or source did not influence body weight, feed conversion, or the incidence of mortality from 1 to 17 d. 4. Decreasing dietary zinc concentration from 120 to 40 mg/kg reduced zinc excretion by 50%. 5. Copper excretion was decreased by 35% as supplemental copper was reduced from 12 to 4 mg/kg. 6. Reducing dietary zinc and copper concentrations can potentially decrease the accumulation of heavy metals in the environment without compromising bird performance.     

Digestible lysine requirement for growing Japanese quails

A total of 1,000 one-day-old Japanese quails were distributed at random, with 5 digestible lysine levels, in 10 replicates and with 20 birds per experimental unit. The basal diet was formulated based on corn and soybean, with 200.6 g CP/kg, 2900.00 kcal/kg ME, and 8.8 g digestible lysine/kg. This basal diet was supplemented with L-lysine HCl (784 g/kg), replacing glutamic acid, and corresponding to digestible lysine levels of 8.8 g/kg, 9.8 g/kg, 10.8 g/kg, 11.8 g/kg, and 12.8 g/kg. The increase in the levels of digestible lysine produced a greater weight gain in birds with up to 12.2 and 12.1 g of lysine/kg at 40 d of age. Carcass weight increased as levels were increased to up to 11.85 g of lysine/kg, and, similarly, egg production per bird housed increased up to 12.03 g of lysine/kg. A linear increase took place in the growing phase for feathering, fat, and crude protein deposits in the carcass, feed intake, and lysine intake. Egg production and egg mass per bird per d increased linearly in the laying phase with the weight gain of birds decreasing linearly until 100 d of age, and, similarly, the feed conversion per egg mass linearly improved in function of the lysine levels. A level of 11.85 g of digestible lysine/kg in the diet, which corresponded to a lysine intake of 120.5 mg/bird/d, provided better carcass weight at the end of the growing phase and better performance at the beginning of the laying phase for the Japanese quails.     

The effects of dry extrusion temperature of whole soybeans on digestion of protein and amino acids by steers

Five Holstein steers (450 kg) with cannulas in the rumen, proximal duodenum, and terminal ileum were used in a 5 x 5 Latin square design to study the effects of extrusion temperature on site of digestion of nitrogenous compounds in whole soybeans. The basal diet contained 50% corn silage, 24% alfalfa hay, 16.6% corn starch, 4.05% ground corn, 1% urea, and 3.4% soybean oil. Raw soybeans or soybeans extruded at 116, 138, or 160 degrees C (diets 116, 138, and 160, respectively) replaced the soybean oil and most of the corn starch in the test diets. Total N (g/d) reaching the duodenum was 232, 293, 285, 308, and 299 for the basal, raw, 116, 138, and 160 diets, respectively. No differences were observed between the raw and extruded soybeans (P = 0.81), or for the linear or quadratic effects of extrusion temperature (P = 0.56 and P = 0.45, respectively). Nonbacterial N (g/d) reaching the duodenum was 63.1, 104.6, 106.7, 101.9, and 113.9 for the same diets, respectively, and was not influenced by extrusion or extrusion temperature. Nitrogen disappearance from the small intestine (g/d) was 150 for the basal diet, 194 for the raw soybean diet, and 187,221, and 213 for the 116,138, and 160 degrees C extruded diets, respectively; no differences were observed between the raw and the extruded soybeans, or for diets containing soybeans extruded at different temperatures. Nitrogen disappearance (% of N entering) from the small intestine was lower (P < 0.05) for steers fed the basal diet than for steers fed the soybean-supplemented diets (64.1 vs 68.5%). No differences (P > 0.10) due to extrusion temperature were detected for flows of individual, essential AA, nonessential AA, and total AA at the duodenum. As extrusion temperatures increased, there were linear increases (P < 0.10) in disappearance (g/d) of all individual AA from the small intestine except for methionine and glycine. Essential, nonessential, and total AA disappearance from the small intestine were increased linearly (P < 0.10) with increasing extrusion temperature. Extrusion of soybeans can protect soy protein against extensive ruminal degradation without compromising intestinal digestibility.