首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献，搜索用时 31 毫秒
1.
Two lamb digestion and three steer growth experiments were conducted to study the feeding value of alfalfa harvested as direct-cut silage (DCS) with grain added prior to ensiling or as low-moisture silage (LMS) or hay with grain added at feeding. In all experiments, alfalfa-grain mixtures contained approximately 50% alfalfa and 50% concentrate (dry matter [DM] basis). In Exp. 1, lambs fed DCS alone consumed less DM than lambs fed LMS or hay alone or any of the alfalfa-grain mixtures. Apparent digestibilities of DM and fiber components were higher (P less than .05) for DCS than for LMS or hay. Lambs that were fed LMS digested more (P less than .05) DM and fiber components than lambs fed hay. Addition of grain resulted in increased (P less than .05) DM digestibility and decreased (P less than .05) digestibilities of neutral detergent fiber and acid detergent fiber. In Exp. 2, growing steers (271 kg) fed DCS-grain had increased (P less than .05) weight gains compared with steers fed hay-grain. Steers fed any of the alfalfa-grain mixtures gained weight more rapidly (P less than .05) than steers fed corn silage (CS)-based diets. In a third experiment, finishing steers (283 kg) fed DCS-grain, LMS-grain, hay-grain or CS-based diets performed similarly (P greater than .05), although steers fed DCS-grain had higher (P less than .05) dressing percentages and yield grades than steers that were fed the other three diets and were fatter (P less than .05) than those fed LMS-grain or CS. In Exp. 4, lambs fed DCS-grain or LMS-grain had higher (P less than .05) apparent DM and organic matter digestibilities than lambs fed CS-based diets with similar forage:grain proportions. In Exp. 5, finishing steers (326 kg) fed DCS-grain gained similarly (P greater than .05) to steers fed LMS-grain or an 85% concentrate diet based on high-moisture corn. Steers fed CS diets had lower (P less than .05) gains and increased (P less than .05) feed per gain compared with steers fed DCS-grain, LMS-grain or high-moisture corn.  相似文献   

2.
Effects of niacin or niacinamide in diets containing either soybean meal, raw whole soybeans or whole soybeans extruded at 132 and 149 C on ruminal bacterial fermentation were examined with a dual-flow continuous culture system. In Exp. 1, soybean sources each provided 50% of total crude protein in diets comprised of 52% concentrate mix, 36% corn silage and 12% alfalfa hay (dry-matter basis). Each diet was supplemented with 0 or 100 mg/kg niacin. Niacin supplementation increased (P less than .05) total nonstructural carbohydrate digestibility and lowered (P less than .05) butyrate concentration. There was also an increase (P less than .10) in amino acid effluent flow from 8,413.3 to 8,665.3 mg/d with addition of niacin to the diet. In Exp. 2, diets were supplemented with 0 or 100 mg/kg of niacin or niacinamide. The total mixed diet was comprised of 60% concentrate mix, 20% corn silage and 20% alfalfa hay (dry matter basis). Acid detergent fiber and cellulose digestibilities and total amino acid effluent flow were higher (P less than .10) with niacinamide supplementation. Niacin or niacinamide had no effect on dry matter and organic matter digestibilities, ammonia-N, total VFA concentration or crude protein degradation. Contrary to results found in other studies, niacin or niacinamide supplementation had no effect on bacterial protein synthesis.  相似文献   

3.
Four experiments were conducted to evaluate three crude protein (CP) sources (urea, U; soybean meal, SBM; corn gluten meal, CGM) in diets based on corn silage (high energy) or grass hay (low energy). In Exp. 1 and 2, growing steers were fed all combinations of energy and protein source at 10.5 or 12% CP. Steers fed high energy diets or 12% CP had improved (P less than .05) daily gains and feed:gain over 84 d. Protein source had no effect (P greater than .05) on performance except that steers fed U consumed more (P less than .05) feed than those fed CGM. Steers were fed experimental diets to a common weight and switched to an 85% concentrate diet for finishing. During finishing, steers fed low energy diets in the growing period consumed more (P less than .05) feed and had increased (P less than .05) feed:gain compared with those fed high energy diets. Growing lambs were fed the same diets as steers. At 10.5% CP, lambs fed high energy diets had higher (P less than .05) digestibilities of dry matter (DM), organic matter (OM), nitrogen (N) and fiber components, and retained more (P less than .05) N. For lambs on 12% CP, high energy diets had higher (P less than .05) DM and OM digestibilities and lower (P less than .05) N digestibilities. At 12% CP, energy level had no effect (P greater than .05) on N retained. Protein source had no effect (P greater than .05) on N retention. There appeared to be no advantage in supplementing with ruminally undegradable proteins, i.e. CGM, in these experiments.  相似文献   

4.
Two digestion and metabolism experiments were conducted to determine effects of monensin in low-protein diets. Monensin supplementation (27 mg/kg of diet dry matter) of steers (303 kg) fed 8.7% crude protein increased (P less than .01) apparent N digestibility and N retention and decreased (P less than .01) percentage of N apparently absorbed lost in urine. Apparent digestibilities of dry matter, gross energy and acid detergent lignin were increased (P less than .05). Digestibilities of neutral detergent and acid detergent fibers were not affected by monensin. In growing wether goats (15 kg) fed 8.5% crude protein, monensin (23 mg/kg of diet dry matter) improved (P less than .01) apparent N digestibility and apparent N absorption. However, urinary N excretion also increased (P less than .05), resulting in no difference in N retention. Monensin did not affect digestibilities of dry matter or gross energy. Efficiency of feed conversion and average daily gain were improved with monensin supplementation of growing goats fed a low-protein, high-roughage diet. Monensin resulted in typical shift of acetate-to-propionate ratio in both experiments. Results suggest that improved N utilization may account for some benefits of feeding monensin.  相似文献   

5.
Four mature geldings were used in a 4 X 4 Latin Square digestion experiment to determine the digestibility of pelleted diets containing 0. 15, 30 and 45% Nonpareil almond hulls. The four isonitrogenous treatments consisting of almond hulls, oat hay, and alfalfa hay provided approximately 94% dry matter (DM), 11% crude protein (CP), 23-32% acid detergent fiber (ADF) and 4100 kcal/kg gross energy (GE). Each horse consumed a different diet during each of four 14-day trial periods. Horses were fed 10 kg of their assigned diet per day. The horses gained an average of 15 kg over the course of the 8-week study. No feed was refused in any of the trials and there were no signs of adverse reactions to any of the diets. The digestibilities of the four dietary components (DM, CP, ADF and GE) were not affected by horse or trial period. Dry matter and GE digestibilities increased (P<.05) as the almond hull content increased in the four diets (59, 63, 64 and 68% DM digestibility and 57, 61, 61 and 64% GE digestibility, respectively). Acid detergent fiber digestibility was not affected by almond hull content (39, 39, 39 and 42% digestibility, respectively) while CP digestibility decreased as the almond hull content increased in the four diets (69, 62, 66 and 56% digestibility, respectively). Almond hulls appear to be a safe and palatable feed for horses and can be fed up to levels of 45%.  相似文献   

6.
Two experiments were conducted to determine effects of feeding corncobs of various mean particle size (MPS) on ruminal, digestive and metabolic characteristics of early-weaned lambs fed pelleted 74.9% concentrate:25.1% corncob diets. The MPS of corncobs in diets was 6.5, 5.4, 1.4 and .8 mm, respectively. As particle size decreased, percentage starch decreased and percentage neutral detergent fiber (NDF), acid detergent fiber (ADF) and cellulose increased. In Exp. 1, 28 crossbred rams (seven/treatment, avg initial wt, 15.3 kg) were used in a randomized complete-block design. In Exp. 2, lambs from Exp. 1 were re-weighed (avg initial wt, 16.8 kg) and fed the same diets as in Exp. 1. In Exp. 1 and 2, lambs ingested dry matter (DM) equal to 2.68 and 3.74% of body weight, respectively. In Exp. 1, apparent DM digestibility was unaffected by corncob MPS; however, in Exp. 2, DM digestibility was highest (68.8%) for lambs fed the 6.5-mm diet and lowest (63.8%) for those fed the .8-mm diet. Apparent starch digestibility was high (greater than 98.8%) in both experiments. Neutral detergent fiber and ADF digestibilities were highest for lambs fed the 1.4-mm diet (50.5 and 43.6%, Exp. 1; 39.6 and 28.9%, Exp. 2). A dramatic increase (6.8 to 39.1%) in acid detergent lignin (ADL) digestibility was observed in Exp. 1 as corncob MPS decreased. In Exp. 2, ADL digestibilities were similar for lambs fed the 6.5-, 5.4- or 1.4-mm diets (avg value, 5.9%) and highest for those fed the .8-mm diet (29.7%). Nitrogen metabolism was unaffected by corncob MPS. In Exp. 1, digestible energy intake, corrected for urinary losses, did not differ among treatments but in Exp. 2, lambs consuming the 6.5-mm diet had higher corrected digestibility energy intakes (1,926.6 kcal/d) than did those fed other diets (avg, 1,832.4 kcal/d). Ruminal pH sampled 4 h post-feeding was highest for lambs consuming the 6.5-mm diet (6.25) in Exp. 1 and the 1.4-mm diet (5.89) in Exp. 2. Lowest ruminal pH (5.30 and 5.36, respectively) was for lambs consuming the .8-mm diet in Exp. 1 and the 5.4-mm diet in Exp. 2. Ruminal lactate concentrations were variable within and among treatments. Total ruminal volatile fatty acid (VFA) concentrations were similar across treatments but in Exp. 2, there was a shift in molar proportions from acetate to propionate as corncob MPS decreased.(ABSTRACT TRUNCATED AT 400 WORDS)  相似文献   

7.
Two experiments were conducted to investigate the effects of a corn-soybean meal (C-SBM) and a sorghum-soybean meal (S-SBM) diet on reproductive performance and nutrient utilization by sows. In Exp. 1, 75 sows (39 gilts; 36 primiparous) were fed either a C-SBM or a S-SBM gestation diet from breeding to d 109. On d 110, sows were assigned to lactation diets; half of the sows from each dietary treatment were assigned to a lactation diet based on the opposite grain. Sow weight change from d 54 to farrowing was greater (P less than .06) for sows fed S-SBM than for sows fed C-SBM. There was no difference (P greater than .50) in weight change of sows during lactation. Feed consumption during lactation was greater (P less than .01) for sows fed C-SBM than for sows fed S-SBM. Litter size at birth and d 21 did not differ between treatments (P greater than .13). Litter weights at birth were similar, but litters of sows fed C-SBM gained more weight (P less than .05) during the 21-d lactation than those fed S-SBM. There were no differences (P greater than .30) in the number of days from weaning to estrus. In Exp. 2, the energy and N metabolism of the two diets was compared in 12 lactating, primiparous sows from d 15 to 20 of lactation. Dry matter digestibility, DE and ME percentages were not affected by grain source (P greater than .46).(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

8.
Twenty-four third- and fourth-parity crossbred gravid sows were housed in metabolism stalls and randomly allotted to four dietary treatments: corn-alfalfa:orchardgrass hay (46%; CH), CH plus lasalocid (CHL), corn-soybean meal (CS) or CS plus lasalocid (CSL). Daily feed intake was 2.36 kg for CH- and CHL-fed sows and 1.66 kg for CS- and CSL-fed sows. Lasalocid intake was 110 mg X sow-1 X d-1. Total feces and urine were collected during two 5-d collection periods, 40 and 80 d postcoitum. Digestible energy (DE), metabolizable energy (ME), nitrogen (N) retention, dry matter (DM), neutral detergent fiber (NDF) and acid detergent fiber (ADF) digestibilities, and retention of calcium (Ca), total phosphorus (P), magnesium (Mg), sodium (Na) and potassium (K) were determined. Percentage DE and ME were greater (P less than .0001) for CS- and CSL-fed sows (88.3 and 83.4%) than for CH- and CHL-fed sows (65.2 and 61.3%). Lasalocid did not influence (P greater than .05) DE and ME values but decreased (P less than .01) the ME:DE ratio. Percentage N digestibility was greater (P less than .0001) for CS- and CSL-fed sows (85.7%) than for CH- and CHL-fed sows (60.8%), but there was no significant difference in N retention, expressed as a percentage of N intake. Lasalocid increased (P less than .03) percentage N digestibility; however, the diet X additive interaction decreased (P less than .005) grams N retained X sow-1 X d-1 for CSL-fed sows. The CH- and CHL-fed sows digested more grams of DM, NDF and ADF but had lower percentage digestibilities of DM and fiber fractions than did CS- and CSL-fed sows. The diet X additive interaction decreased (P less than .05) percentages of Ca, P and K digested and decreased (P less than .05) grams mineral retained (Ca, P, Mg and K) and mineral retained expressed as a percentage of intake for CSL-fed sows. Results indicate that alfalfa:orchardgrass hay and lasalocid influenced energy, fiber, nitrogen and mineral utilization by gravid sows.  相似文献   

9.
Two experiments were conducted to determine the dietary value of pellets containing kenaf (Hibiscus cannabinus cv. 'Everglade 41') hay. Averaged across both experiments, kenaf pellets contained 82.6% kenaf hay, 16.6% liquid molasses, and 0.8% mineral oil. The chemical composition of the kenaf pellet was 12.6% crude protein (CP), 41.2% neutral detergent fiber (NDF), and 14.4% acid detergent fiber (ADF). In Exp. 1 (digestion and N balance trial), 18 lambs (body weight [BW] = 36.4 kg) were blocked by BW. Lambs were randomly assigned within a block to Diet 1 (59.5% corn and 40.5% alfalfa pellet), Diet 2 (59.7% corn, 28.4% alfalfa pellets, and 11.9% kenaf pellets), or Diet 3 (59.6% corn, 16.5% alfalfa pellets, and 23.9% kenaf pellets). Diets were formulated so that CP was the first-limiting nutrient. Each diet was limit-fed at 2.4% of BW. Replacing alfalfa pellets with kenaf pellets tended to decrease (P = 0.10) CP and ADF intakes, but increased (P = 0.01) DM digestibility. Diet had no effect (P = 0.33) on N balance. In Exp. 2 (dry matter [DM] intake trial), 32 lambs (BW = 30.4 kg) were blocked by gender and BW. Within a block, lambs were randomly assigned to one of four diets in a 2 x 2 factorial arrangement. Main effects were hay (bermudagrass or fescue) and supplemental protein source (kenaf or alfalfa pellets). Lambs were housed in individual pens with ad libitum access to the assigned hay. Supplemental protein was fed (185 g of DM) once daily. Hay intake was measured weekly for 8 wk. Lambs consumed more (P = 0.002) fescue than bermudagrass hay (743 vs 621 g/ d). Lambs fed fescue hay gained weight more rapidly (P = 0.001) than lambs fed bermudagrass hay (120 vs 72 g/d). Hay intake and ADG were similar (P = 0.90) for lambs fed alfalfa or kenaf pellets. Kenaf hay mixed with molasses and mineral oil can be formed into a pellet. In the diets used in this experiments, kenaf pellets can replace alfalfa pellets in diets fed to lambs without altering forage intake, gain, or N retention.  相似文献   

10.
Two experiments involving 1,020 litters were conducted at eight research stations to determine the effects of dietary NaCl (salt) concentration during gestation and lactation on reproductive performance of sows. Primiparous and multiparous sows were fed fortified corn- or grain sorghum-soybean meal diets at 1.82 kg/d during gestation. During the winter months (December, January, February) the feeding level was increased to 2.27 kg/d. Sows had ad libitum access to diets during lactation. Dietary concentrations of added salt were .50 and .25% in Exp. 1 and .25 and .125% in Exp. 2. When more feed was fed during gestation, the salt concentrations were reduced to .40, .20, .20 and .10%, respectively, in order to maintain a constant daily intake of Na and Cl during gestation. Gestation weight gain and lactation (21-d) weight loss of the sows were not affected by dietary salt level in either experiment. In Exp. 1, lowering the salt concentration did not influence the number of pigs farrowed, but it resulted in a .05 kg/pig reduction (P less than .01) in average birth weight. Average 21-d pig weights also tended (P less than .19) to be lower in the low-salt group. There was a decrease in litter size from the first to the second farrowing for sows fed low salt, but not for sows fed the higher salt concentration. In Exp. 2, reducing the salt content from .25 to .125% did not alter reproductive performance. The overall ratio of males to females at birth in the population of greater than 10(4) pigs was 52.3:47.7. Lower salt intakes tended to reduce the percentage of males born in both experiments, although the differences were not significant (P greater than .3). The results indicate that reducing the salt concentration in sows diets from .50 to .25 or .125% reduces birth weight in newborn pigs. When continued for more than one reproductive cycle, feeding less than .5% salt appears to reduce litter size at birth and weaning.  相似文献   

11.
An endophytic fungus found in Kentucky 31 (KY-31) tall fescue has been associated with the "summer syndrome" (fescue toxicity) in grazing cattle. Four experiments were conducted to investigate the use of weanling rats as an animal model to study the fescue toxicity syndrome. When graded levels of fungus-infected (INF) or fungus-free (FF) KY-31 seed were fed, feed intake and growth rates were inversely related to the amount of INF seed in the diet. When diets containing 50% seed were fed, rats eating INF seed had reduced (P less than .05) daily water consumption (9 vs 20 ml) and lowered (P less than .05) body temperatures (36.8 vs 37.7 C) when compared with the FF treatments. Autoclaving the seed increased feed intake and growth rate of rats receiving both INF and FF seed diets, but daily gains continued to be less (P less than .05) in the rats fed autoclaved INF diets when compared with rats fed autoclaved FF diets (2.3 vs 6.8 g). Rats fed diets containing either 40% shredded wheat on which the fescue endophyte had been grown or 40% shredded wheat that was not innoculated did not differ in performance. Crude fiber, nitrogen-free extract, gross energy and dry matter digestibilities were enhanced (P less than .05) by the presence of INF seed in the diets when compared with the FF seed treatments. Crude protein and ether extract digestibilities and apparent biological value of fescue protein were not affected by presence of the fungus. The effect of INF seed on organ weights was inconsistent.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

12.
Three digestion experiments and one growth experiment were conducted to determine site, extent and ruminal rate of forage digestion and rate and efficiency of gain by cattle offered alfalfa haylage supplemented with corn or dry corn gluten feed (CGF). In Exp. 1, eight steers were fed alfalfa haylage-based diets with substitution of corn for 0, 20, 40 or 60% of haylage in a 4 X 4 latin square. Increasing dietary corn substitution increased (P less than .05) OM, NDF and ADF digestion by steers but decreased (P less than .05) rate of in situ alfalfa DM digestion. In Exp. 2, five heifers were fed alfalfa haylage-based diets with increasing dietary levels of CGF in a 5 X 5 latin square. Increasing dietary CGF increased (P less than .05) OM, NDF and ADF digestion by heifers. In Exp. 3 and 4, cattle were fed alfalfa haylage-based diets containing either 20 or 60% corn or CGF. In Exp. 3, supplementation increased (P less than .05) OM and NDF digestion but level X supplement source interaction (P less than .05) occurred, with added CGF increasing OM and NDF digestion more than added corn. In Exp. 4, supplementation improved (P less than .05) DM intake, daily gain and feed efficiency. Dry matter intake and daily gain were greater (P less than .05) for 60% supplementation than for 20% supplementation. Overall, whereas increasing the level of dietary supplement increased (P less than .05) OM, NDF and ADF digestion, only corn addition decreased (P less than .05) rate of in situ alfalfa DM digestion. Daily gains and feed efficiencies were similar in cattle fed either corn or CGF with alfalfa haylage.  相似文献   

13.
The effects of replacing corn and soybean meal with distiller's dried grains and solubles in the weanling horse diet were examined. Sixteen weanling horses, 12 fillies and four colts, were fed completely pelleted diets consisting of 50% alfalfa in addition to 50% of a concentrate containing either corn and soybean meal (CS), or 30% of the concentrate replaced with distiller's dried grains with solubles (DDGS). There were no significant differences (P > .05) between the two diets in either average daily gain or gain-to-feed ratio. The CS diet had a higher apparent dry matter digestibility (P < .0001), and higher apparent digestibility of crude protein (CP), acid detergent fiber (ADF), and neutral detergent fiber (NDF) (P < .01). It was concluded that replacing a portion of the corn and soybean meal with distiller's dried grains with solubles in the weanling horse diet did not lead to significant growth depression. However, the diet containing DDGS had reduced apparent digestibility of dry matter, CP, and fiber. Therefore, it was concluded that it may not be advisable to replace more than 30% of the concentrate portion or 15% of the total diet with distiller's dried grains and solubles when alfalfa is used as the forage source constituting 50% of the weanling diet. Even less DDGS may be desirable to substitute for corn and soybean meal in weanling horse diets if the forage source is one with lower protein quality than alfalfa. It is possible that using DDGS for less than 30% of the concentrate portion of the diet along with high-quality alfalfa forage may produce comparable gain and feed efficiency results with less depression of apparent digestibility of dry matter, crude protein, and fiber.  相似文献   

14.
Associative effects of sorghum silage and sorghum grain diets   总被引：5，自引：0，他引：5  
A metabolism trial was conducted to quantitate associative effects between sorghum silage and sorghum grain, and to identify responsible factors. Diets were formulated by mixing ground sorghum grain (0, 15, 30, 45 and 60% of diet dry matter) with sorghum silage and were adjusted to 15.0% crude protein with soybean meal. Cannulated Beefmaster-cross steers (300 kg) were adapted to diets for 14 d followed by 5 d of fecal collection during which digestibility of components was determined. Intake of digestible dry matter and digestibilities of dry matter and neutral detergent fiber increased with increases in diet grain content (linear effect: P less than .01, P less than .01, P less than .05, respectively; quadratic effect: P less than .05, P less than .005, P less than .06, respectively). Digestibilities of starch, crude protein and hemicellulose were not significantly affected by grain level. Ruminal pH averaged 6.0 and was not significantly affected by grain level or time of sampling. Ruminal in situ digestion of neutral detergent fiber and acid detergent fiber at 48 h decreased (linear contrast, P less than .001) with increasing grain content. Rate of passage of liquid digesta was not affected by grain level in the diet. The rate of passage of particulate digesta decreased linearly (P less than .005, orthogonal contrast) with increasing levels of grain. Low levels of sorghum grain (15 and 30%) improved digestibility and intake of digestible dry matter of sorghum silage-based diets, whereas higher rates of grain supplementation (45 and 60%) did not result in further improvement.  相似文献   

15.
Four mature crossbred sows were fistulated in the cecum, with two sows fed a corn-alfalfa:orchardgrass hay (46%) diet (CH) and two fed a corn-soybean meal diet (CS). Four experiments were conducted to evaluate buffers, incubation times, buffer pH and substrate and inocula sources in an in vitro, anaerobic, mixed-culture system. In vitro dry matter digestibility (IVDMD) and substrate solubility in buffer (SS) were determined. In Exp. 1, substrates were CH and CS diets with cecal inocula obtained from CH- and CS-fed sows. The bicarbonate (B) buffer resulted in lower (P less than .01) and less variable SS for all treatments. In vitro dry matter digestibility was higher (P less than .01) for the CS diet at both 24 and 48 h incubation. Use of the B buffer also resulted in higher (P less than .001) IVDMD values. In Exp. 2, substrates were either as in Exp. 1 or were freeze-dried cecal contents (CC) from CH- or CS-fed sows. In vitro dry matter digestibility of CC was lower (P less than .006) than IVDMD of diet, while IVDMD was higher (P less than .02) with cecal inocula than fecal inocula. In Exp. 3, substrate-inocula treatments were CH-CH, CH-CS, CS-CH and CS-CS. Substrate solubility was lower (P less than .05) at pH 5.8 than at pH 6.8. In vitro dry matter digestibility was higher when substrate and inocula were from the same source and at pH 5.8. In Exp. 4, CC and inocula were from sows fed CH and CS diets with or without lasalocid. In vitro dry matter digestibility was higher with CC from lasalocid-fed sows and inocula from sows fed no lasalocid. The CH diet resulted in higher acetate (Ac) and lower propionate (Pr) molar proportions than did the CS diet, while lasalocid increased molar proportion Pr and decreased molar proportion Ac in cecal contents from sows fed either diet. Corn-alfalfa:orchardgrass hay-fed sows had a faster rate of digesta passage and shorter cecal retention time than did CS-fed sows.  相似文献   

16.
An experiment was conducted to compare apparent total tract protein digestibilities and apparent ileal digestibilities of protein and amino acids in growing pigs and adult pregnant and lactating sows. Twelve growing pigs and 12 sows were used and surgically fitted with simple T-cannulas at the distal ileum. Six experimental diets based on corn, barley, wheat, soybean meal, canola meal, or meat and bone meal were formulated, and each diet was fed to growing pigs, gestating sows, and lactating sows for 7 d. Chromium oxide was included in all diets as an indigestible marker (.25%) for calculating nutrient digestibilities. Fecal material was collected on d 5 of each feeding period by grab sampling, and ileal samples were collected for 12 h/d during the last 2 d of each feeding period. Apparent fecal protein digestibilities for all feed ingredients were higher (P < .05) in gestating and lactating sows compared to growing pigs, but no differences between the two groups of sows were observed (P > .05). At the distal ileum, no differences (P > .05) in protein digestibilities were detected between sows and growing pigs regardless of feed ingredient. For all feed ingredients tested, lactating sows had apparent ileal digestibilities of most amino acids that were two to six percentage units higher than those obtained in growing pigs, but not all of the differences were significant. Gestating sows had digestibilities of most amino acids that were intermediate between those of growing pigs and lactating sows. The combined results from the six feed ingredients showed that lactating sows had higher (P < .05) digestibilities of all indispensable amino acids except arginine, and gestating sows had higher (P < .05) digestibilities of five of the indispensable amino acids than did growing pigs. The results of this experiment indicate that apparent fecal protein and apparent ileal amino acid digestibilities obtained in growing pigs are not always representative of digestibilities in either gestating or lactating sows.  相似文献   

17.
This study was conducted to determine whether feeding different physical forms of hay alters nutrient digestibility and nitrogen retention (NR). Six Quarter Horse geldings were assigned to any one of three different dietary treatments in three 14-day periods. The diets included long-stem Bermuda grass hay (G), long-stem alfalfa hay (A), and alfalfa cubes (C). In the final 4 days of each period, horses were fitted with harnesses for total collection of urine and feces. Samples of feed, orts, feces, and urine were analyzed for dry matter, organic matter, acid detergent fiber, neutral detergent fiber, and nitrogen (N). Digestibility of dry matter, organic matter, and N was greatest for A, intermediate for C, and smallest for G (P < .05). Digestibility of acid detergent fiber was greater (P < .05) for A than G or C, and neutral detergent fiber digestibility was greater (P < .05) for A or G than C. Nitrogen intake (NI) was greatest for A, intermediate for C, and smallest for G (P < .05). Fecal N excretion was not different between diets, but urine N excretion was greater (P < .05) for A and C as compared with G. When expressed as a percentage of NI, NR did not differ among diets. We concluded that NR in mature horses increases with NI, but N utilization is not significantly influenced by the physical form or crude protein content of the hay fed. Potential differences in fiber digestibility and daily fecal output are factors to consider when incorporating processed forages into feeding programs of horses.  相似文献   

18.
Corn gluten feed (CGF) was evaluated as the primary energy and protein source for gestating sows. Eighty gravid multiparous Yorkshire x Landrace sows were assigned randomly to three treatment groups for the entire three-parity trial. The gestation treatment diets were 1) corn-soybean meal fed at 1.8 kg/d (control), 2) CGF plus soybean meal fed at 2.3 kg/d (CGF-low) and 3) CGF plus soybean meal fed at 2.6 kg/d (CGF-high). The CGF diets contained 92.2% and 93.7% CGF, respectively. Feeding levels of Diets 2 and 3 were based on the assumption that CGF had 80% and 70% of the net energy value of corn, respectively. All sows had ad libitum access to a conventional corn-soybean meal diet during lactation and were fed 3.2 kg/d during breeding. Intakes of gestation treatment diets were increased 25% during winter months. Based on litter size and weight, the performance of sows fed CGF did not differ from that of the sows fed the control diet. Mean number of pigs at birth and 21 d (weaning) for the three parities were: (control) 10.16, 7.65; (CGF-low) 11.30, 8.44; (CGF-high) 10.73, 8.13, respectively. Pigs from CGF-fed sows were smaller at birth (P less than .05), but subsequent pig weights did not differ. Mean pig birth and 21-d weights for the three parities were: (control) 1.44, 5.18; (CGF-low) 1.30, 4.84; (CGF-high) 1.31, 5.01 kg, respectively. CGF-low sows weighed less (P less than .01) at d 109 of gestation than did the control and CGF-high sows, which did not differ in weight.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

19.
Two metabolism trials were conducted with yearling steers fed mature native forage to measure the effect of supplemental protein degradability on selected metabolic variables. Supplements contained 40% crude protein equivalence. In Trial 1, four abomasal-cannulated steers weighing 290 to 379 kg were fed supplements containing the following N sources: (1) 15% corn, 85% urea (U); (2) 100% soybean meal (SBM); (3) 10% corn, 40% soybean meal, 50% urea (SBM-U) and (4) 14% corn, 36% blood meal, 50% urea (BM-U). Equal portions of the daily diet (2.2% of body weight) were fed every 2 h. Treatment differences were not significant for organic matter digestibility, abomasal organic matter flow, nonammonia N flow, feed N flow, bacterial N flow and efficiency of microbial protein synthesis. There was a positive (P less than .05) relationship between quantity of slowly degraded protein fed and nonammonia N flow (r = .97) or feed N flow (r = .98). Escape N was determined to be 21.5, 16.5 and 54.2% in SBM, SBM-U and BM-U supplements, respectively. In the second trial, no supplement, SBM, SBM-U and BM-U were fed in a N balance trial. Dry matter, crude protein and neutral detergent fiber digestibilities were higher (P less than .05) for steers fed supplemented diets. Acid detergent fiber digestibility was higher (P less than .05) for steers supplemented with SBM than steers fed the unsupplemented diets. Nitrogen retention was greater (P less than .05) for cattle fed SBM and BM-U than for cattle fed SBM-U or no supplement.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

20.
Two metabolism studies were conducted with 24 (Exp. 1) and 36 (Exp. 2) crossbred barrows (initial weight 35 kg) to determine the effect of corn type--normal corn (NC) and high-lysine corn (HLC)--and storage method--dry (D), high-moisture (HM) and reconstituted (RC)--on energy and N digestibility. Diets fed in Exp. 1 were: 1, NC-soybean meal formulated at .78% lysine (dry matter basis); 2, HLC-soybean meal containing the same amount of corn as diet 1 (.87% lysine); 3, HLC-soybean meal with the same lysine level as diet 1. In Exp. 1, dry matter, energy and N digestibilities were not different between corn types or lysine levels (P greater than .16). These results indicate that energy and N digestibility of HLC in typical diets for growing swine are similar to those for NC diets when both are balanced on a lysine basis. Also, replacing NC with HLC on an equal-weight basis did not affect energy and N digestibility. In Exp. 2 six diets balanced on an isonitrogenous and dry-matter basis were tested. Normal corn and HLC diets, which had been stored by three different methods (D, HM and RC) were arranged in a 2 X 3 factorial plan. There were no differences between corn types in dry matter, energy and N digestibilities. The HM and RC treatments had larger particle sizes than the dry corn diets. For diets balanced on an isonitrogenous basis, dry corn storage improved energy digestibility (P less than .10). Reconstitution appeared to improve energy balance and N digestibility of HLC, while HM storage improved energy balance and N digestibility of NC.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号