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1.
There are conflicting results on the growth and health of weanling pigs (Sus scrofa) fed high-fiber diets, and responses may differ according to sanitary conditions. This study was conducted to explore the growth, health, and fecal microbiota of weanling pigs fed either low- or high-fiber diets in 2 different sanitary conditions. Forty-eight pigs weaned at 28 d of age were individually housed in "good" (clean) or "poor" (unclean) sanitary conditions. During 2 consecutive phases, pigs were fed 2 diets containing a low (control) or high level of fiber: 121 or 169 g/kg total dietary fiber (TDF) for Phase I and 146 or 217 g/kg for Phase II, which lasted 15 and 20 d, respectively. This led to 4 experimental treatments in Phase I in a 2 × 2 factorial arrangement (2 sanitary conditions × 2 diets) and 8 experimental treatments in Phase II in a 2 × 2 × 2 factorial arrangement (2 sanitary conditions × 2 diets in Phase I × 2 diets in Phase II). The poor sanitary conditions led to a reduced G:F (0.617 vs. 0.680 for poor and good sanitary conditions, respectively; P = 0.01) over the entire experimental period. The number of pigs with diarrhea in Phase I tended to be greater in the poor sanitary conditions with the high-fiber diet than the control diet (7 vs. 3 pigs, P = 0.07). Enterococcus was prominent in feces of these diarrheic pigs. At 5 wk after weaning, compared with good sanitary conditions, the fecal microbiota of pigs housed in poor sanitary conditions was characterized by more Lactobacillus (9.24 vs. 8.34 log cfu/g, P < 0.001), more Enterobacteria (6.69 vs. 5.58 log cfu/g, P < 0.001), and less anaerobic sulfite bacteria (3.72 vs. 5.87 log cfu/g; P < 0.001). The feces of pigs in poor sanitary conditions contained more total VFA and proportionally more butyrate (9.7 vs. 5.7% for poor and good conditions, respectively, independently of dietary treatment, P < 0.001). At 5 wk after weaning, feces of pigs fed the high-fiber diet during Phase II contained less Enterococcus bacteria than pigs fed the control diet (4.06 vs. 4.56 log cfu/g; P = 0.05), and more total VFA with a decreased proportion of branched-chain fatty acids (5.0 vs. 6.1%; P = 0.006). To conclude, feeding pigs a high-fiber diet in the immediate period after weaning is probably an additional risk factor for slower BW gain, especially in poor sanitary conditions.  相似文献   

2.
The effects of source and level of dietary NDF on intake, ruminal digestion in situ, ruminal fermentation, and total tract digestion were evaluated in Hereford steers using a replicated 5 x 5 Latin square design. Diets contained 62 to 64% TDN and included 1) 80% control concentrate (contained pelleted ground grains) and 20% timothy hay (traditional diet), 2) 80% control concentrate and 20% alfalfa cubes, 3) 90% control concentrate and 10% cubes, 4) a completely pelleted diet using corn cobs as the primary NDF source, and 5) 80% textured (rolled instead of ground grains) concentrate and 20% hay. Dry matter intake differed (P less than .05) between the traditional and cube diets due to limited acceptance of alfalfa cubes. Increased (P less than .05) ruminal osmolality, total VFA, and NH3 N and lower (P less than .01) ruminal pH in steers fed corn cob and cube diets relative to steers fed the traditional diet were due to preferential consumption of concentrate over supplemental roughage and the resultant rapid fermentation of concentrates. Potentially degradable DM in the traditional diet exceeded (P less than .06) all other diets, resulting in the increased (P less than .10) extent of DM disappearance despite a slower (P less than .05) rate of DM disappearance. Rate of NDF disappearance and all in situ starch disappearance parameters were similar between the traditional, corn cob, and cube diets. All ruminal digestion parameters involving NDF disappearance were similar between hay diets and between cube diets, whereas rate and extent of starch disappearance differed (P less than .05) between hay diets. Although formulation of diets with different sources of dietary NDF did not affect total tract digestion of nutrients, nutrient availability and ruminal fermentation were altered due to dietary differences in sources of dietary NDF and preferential selection of feedstuffs by steers.  相似文献   

3.
Two experiments were conducted to evaluate the effects of dietary Zn and Fe supplementation on mineral excretion, body composition, and mineral status of nursery pigs. In Exp. 1 (n = 24; 6.5 kg; 16 to 20 d of age) and 2 (n = 24; 7.2 kg; 19 to 21 d of age), littermate crossbred barrows were weaned and allotted randomly by BW, within litter, to dietary treatments and housed individually in stainless steel pens. In Exp. 1, Phases 1 (d 0 to 7) and 2 (d 7 to 14) diets (as-fed basis) were: 1) NC (negative control, no added Zn source); 2) ZnO (NC + 2,000 mg/kg as Zn oxide); and 3) ZnM (NC + 2,000 mg/kg as Zn Met). In Exp. 2, diets for each phase (Phase 1 = d 0 to 7; Phase 2 = d 7 to 21; Phase 3 = d 21 to 35) were the basal diet supplemented with 0, 25, 50, 100, and 150 mg/kg Fe (as-fed basis) as ferrous sulfate. Orts, feces, and urine were collected daily in Exp. 1; whereas pigs had a 4-d adjustment period followed by a 3-d total collection period (Period 1 = d 5 to 7; Period 2 = d 12 to 14; Period 3 = d 26 to 28) during each phase in Exp. 2. Blood samples were obtained from pigs on d 0, 7, and 14 in Exp. 1 and d 0, 7, 21, and 35 in Exp. 2 to determine hemoglobin (Hb), hematocrit (Hct), and plasma Cu, (PCu), Fe (PFe), and Zn (PZn). Pigs in Exp. 1 were killed at d 14 (mean BW = 8.7 kg) to determine whole-body, liver, and kidney mineral concentrations. There were no differences in growth performance in Exp. 1 or 2. In Exp. 1, pigs fed ZnO or ZnM diets had greater (P < 0.001) dietary Zn intake during the 14-d study and greater fecal Zn excretion during Phase 2 compared with pigs fed the NC diet. Pigs fed 2,000 mg/kg, regardless of Zn source, had greater (P < 0.010) PZn on d 7 and 14 than pigs fed the NC diet. Whole-body Zn, liver Fe and Zn, and kidney Cu concentrations were greater (P < 0.010), whereas kidney Fe and Zn concentrations were less (P < 0.010) in pigs fed pharmacological Zn diets than pigs fed the NC diet. In Exp. 2, dietary Fe supplementation tended to increase (linear, P = 0.075) dietary DMI, resulting in a linear increase (P < 0.050) in dietary Fe, Cu, Mg, Mn, P, and Zn intake. Subsequently, a linear increase (P < 0.010) in fecal Fe and Zn excretion was observed. Increasing dietary Fe resulted in a linear increase in Hb, Hct, and PFe on d 21 (P < 0.050) and 35 (P < 0.010). Results suggest that dietary Zn or Fe additions increase mineral status of nursery pigs. Once tissue mineral stores are loaded, dietary minerals in excess of the body's requirement are excreted.  相似文献   

4.
Considering the different potential benefits of divergent fiber ingredients, the effect of 3 fiber sources on energy and macronutrient digestibility, fermentation product formation, postprandial metabolite responses, and colon histology of overweight cats (Felis catus) fed kibble diets was compared. Twenty-four healthy adult cats were assigned in a complete randomized block design to 2 groups of 12 animals, and 3 animals from each group were fed 1 of 4 of the following kibble diets: control (CO; 11.5% dietary fiber), beet pulp (BP; 26% dietary fiber), wheat bran (WB; 24% dietary fiber), and sugarcane fiber (SF; 28% dietary fiber). Digestibility was measured by the total collection of feces. After 16 d of diet adaptation and an overnight period without food, blood glucose, cholesterol, and triglyceride postprandial responses were evaluated for 16 h after continued exposure to food. On d 20, colon biopsies of the cats were collected under general anesthesia. Fiber addition reduced food energy and nutrient digestibility. Of all the fiber sources, SF had the least dietary fiber digestibility (P < 0.05), causing the largest reduction of dietary energy digestibility (P < 0.05). The greater fermentability of BP resulted in reduced fecal DM and pH, greater fecal production [g/(cat × d); as-is], and greater fecal concentration of acetate, propionate, and lactate (P < 0.05). For most fecal variables, WB was intermediate between BP and SF, and SF was similar to the control diet except for an increased fecal DM and firmer feces production for the SF diet (P < 0.05). Postprandial evaluations indicated reduced mean glucose concentration and area under the glucose curve in cats fed the SF diet (P < 0.05). Colon mucosa thickness, crypt area, lamina propria area, goblet cell area, crypt mean size, and crypt in bifurcation did not vary among the diets. According to the fiber solubility and fermentation rates, fiber sources can induce different physiological responses in cats, reduce energy digestibility, and favor glucose metabolism (SF), or improve gut health (BP).  相似文献   

5.
A digestion and ruminal fermentation trial involving five ruminally cannulated steers assigned to a 5 x 5 Latin square with a 2 x 2 + 1 arrangement of dietary treatments was conducted to evaluate the effects of variety of rapeseed silage (RS) containing either a high (HG) or a low (LG) glucosinolate concentration when fed at 100 or 50% of diet DM. A bromegrass hay-corn-soybean meal mixture, which was expected to be isocaloric and isonitrogenous with the RS, was used as the control (C) treatment and replaced RS in the 50% diets. In situ disappearance of substrate from both RS varieties was measured in ruminal environments created by each diet. No dietary treatment x RS substrate interactions were observed for any in situ variable. Total tract digestibility and extent of in situ disappearance of both DM and NDF were greater (P less than .01) for HG than for LG. In situ DM and NDF disappearance at 8, 16 and 24 h was greater (P less than .01) for RS than for the C diet. Similarly, total tract DM digestibility was greater (P less than .01) for RS (61.0%) vs C (56.0%) diets. Diets with 50% RS had greater (P less than .01) NDF digestibility (50.4%) than 100% RS (43.6%) diets. Variety of RS had no effect on particulate passage rate. In a 77-d growth trial with 60 beef steers, ADG was greater (P less than .01) for HG vs LG (.46 vs .36 kg), 50 vs 100% (.52 vs .31) and C vs RS (.64 vs .41) diets.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

6.
Three balance trials, each involving 12 crossbred gilts averaging 35.2 kg body weight, were conducted to determine the effects of dietary fiber and virginiamycin on nutrient digestibility, mineral absorption and retention, and digesta rate of passage (RP). Two levels of fiber (13.5 and 20.2% neutral detergent fiber) and two levels of virginiamycin (0 and 11 ppm) were used in a 2 X 2 factorial arrangement of treatments. All diets were isonitrogenous and isocaloric. The RP was determined by observing the time required for a change in feces color after the addition of .5% chromic oxide to the diet. The high fiber diet had a faster (P less than .01) RP, which was associated with depressions (P less than .001) in the digestibility of dry matter (DM), energy (E), cell contents, neutral detergent fiber (NDF), acid detergent fiber (ADF), hemicellulose (HC), cellulose, permanganate lignin and ash. Virginiamycin supplementation slowed (P less than .004) the RP of both low and high fiber diets, but improved (P less than .05) the DM, E, NDF, ADF, HC and cellulose digestibility of the high fiber diet only. Fiber increased (P less than .06) fecal N excretion, whereas virginiamycin supplementation decreased (P less than .08) fecal N excretion. The addition of virginiamycin improved the absorption and retention of P, Ca, Mg, Cu, Fe, Zn and Mn when added to the high fiber diet, but had little or no effect when added to the low fiber diet even though absorption and retention values for most minerals were similar or slightly higher for the unsupplemented high fiber diet compared with the unsupplemented low fiber diet.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

7.
Fourteen Holstein steers (446 +/- 4.4 kg of initial BW) with ruminal, duodenal, and ileal cannulas were used in a completely randomized design to evaluate effects of whole or ground canola seed (23.3% CP and 39.6% ether extract; DM basis) on intake, digestion, duodenal protein supply, and microbial efficiency in steers fed low-quality hay. Our hypothesis was that processing would be necessary to optimize canola use in diets based on low-quality forage. The basal diet consisted of ad libitum access to switchgrass hay (5.8% CP; DM basis) offered at 0700 daily. Treatments consisted of hay only (control), hay plus whole canola (8% of dietary DM), or hay plus ground canola (8% of dietary DM). Supplemental canola was provided based on the hay intake of the previous day. Steers were adapted to diets for 14 d followed by a 7-d collection period. Total DMI, OM intake, and OM digestibility were not affected (P > or = 0.31) by treatment. Similarly, no differences (P > or = 0.62) were observed for NDF or ADF total tract digestion. Bacterial OM at the duodenum increased (P = 0.01) with canola-containing diets compared with the control diet and increased (P = 0.08) in steers consuming ground canola compared with whole canola. Apparent and true ruminal CP digestibilities were increased (P = 0.01) with canola supplementation compared with the control diet. Canola supplementation decreased ruminal pH (P = 0.03) compared with the control diet. The molar proportion of acetate in the rumen tended (P = 0.10) to decrease with canola supplementation. The molar proportion of acetate in ruminal fluid decreased (P = 0.01), and the proportion of propionate increased (P = 0.01), with ground canola compared with whole canola. In situ disappearance rate of hay DM, NDF, and ADF were not altered by treatment (P > or = 0.32). In situ disappearance rate of canola DM, NDF, and ADF increased (P = 0.01) for ground canola compared with whole canola. Similarly, ground canola had greater (P = 0.01) soluble CP fraction and CP disappearance rate compared with whole canola. No treatment effects were observed for ruminal fill, fluid dilution rate, or microbial efficiency (P > or = 0.60). The results suggest that canola processing enhanced in situ degradation but had minimal effects on ruminal or total tract digestibility in low-quality, forage-based diets.  相似文献   

8.
The effects of two types of nondigestible oligosaccharides (NDO), fructooligosaccharides (FOS), and transgalactooligosaccharides (TOS) were studied on growing and weanling pigs' nutrient digestion. Dietary NDO were included at the expense of purified cellulose. Twenty-five 57-d-old growing pigs, averaging 15.9+/-.6 kg on d 0 of the experiment, were fed a corn-based control diet or the control with 6.8 or 13.5 g of FOS/kg or 4.0 or 8.0 g of TOS/kg (five pigs per diet). Feces were collected on d 28 to 32, and small-intestinal digesta were collected (slaughter technique) on d 42 to 47 of the experiment. Feeds, feces, and digesta were analyzed for DM, inorganic matter, CP, ether extract, and crude fiber. Dietary NDO did not significantly affect apparent fecal and small intestinal digestion of nutrients in growing pigs. After being fed a NDO-free diet through d 10 after weaning, 38-d-old weanling pigs (n = 20), averaging 10.4+/-.8 kg on d 0 of the experiment, were fed a control diet (based on cornstarch, casein, and oat husk meal) or the control with 10 or 40 g of FOS or TOS/kg (four pigs per diet). Feces and urine were collected on d 13 to 17, and ileal digesta were collected via a postvalve T-cecum cannula on d 33 to 37 of the experiment. Feeds, feces, and digesta were analyzed for DM, inorganic matter, CP, ether extract, starch, NDF, ADF, ADL, Ca, P, Mg, Fe, Cu, and Zn. Nonstarch neutral-detergent soluble carbohydrates (NNSC) completed the mass balance for the carbohydrates. Urine was analyzed for N and minerals. The apparent fecal digestion of NNSC increased in the NDO-supplemented diets. The TOS-fed pigs tended (P<.10) to have a higher apparent fecal digestion of CP than the FOS-fed and control pigs but excreted more N via the urine (P<.01). Nitrogen and mineral balances were not affected. The FOS was nearly completely degraded prececally. Mean fiber digestion was lower at the fecal compared with the ileal level, as was the extent of NDO effects. This indicates that fiber digestion requires more than 2 wk to adapt to dietary NDO. Apparent ileal digestion of hemicellulose increased for the NDO-supplemented diets (P<.05), but that of NNSC decreased (P<.001). Thus, under the well-controlled conditions of this experiment, dietary NDO hardly affected nutrient digestion in well-kept growing and weanling pigs. However, digestion of dietary nonstarch carbohydrates may be affected.  相似文献   

9.
Eight crossbred male horses aged 12 +/- 5 yr and with BW of 305 +/- 18 kg were used in pairs in a 4 x 4 Latin square design with 4 ground and pelleted diets. Each pair included a cecum and right ventral colon-fistulated animal and a cecal-fistulated animal. The 4 horse diets were a high-fiber diet (HF+0) based on dehydrated alfalfa, a high-starch diet based on barley and wheat bran (HS+0), and the HF or HS diets supplemented with Saccharomyces cerevisiae (SC) CBS 493.94 (HF+SC and HS+SC). The probiotic preparation contained 4.5 x 10(9) cfu/g of live yeast mixed with the culture medium, and was top-dressed onto the feed pellets at a rate of 10 g/d, equally distributed between the 2 daily meals. All 4 diets were offered in the same quantities (18.0 g of pelleted feed DM + 3.5 g of long wheat straw/kg of BW per d). Each of the 4 experimental treatments was divided into a 21-d period of diet adaptation followed by a 10-d period of total fecal collection for digesta flow rate and apparent digestibility measurements. Three markers were used to measure mean retention time (MRT) of the feed particles: Yb bound to the pelleted feeds for MRT in the whole digestive tract (MRT(Yb)), Eu bound to the pelleted feeds, and Dy bound to the fecal particles for MRT in the hindgut (MRT(Eu) and MRT(Dy)). Apparent digestibilities of DM, OM, and CP were greater (P < 0.001) in the HS than HF diet, independently of SC supplementation, whereas ADF digestibility was greatest in the HF diet (P = 0.035). Cellulolytic activity estimated through the in vitro disappearance rate of the dietary ADF fraction (IVAD(ADF)) was less (P < 0.001) in the HS than the HF diet. There was no dietary effect on NDF digestibility due to the longer MRT(Eu) of small particles in the hindgut (P = 0.036), which compensated for the lower fibrolytic activity expressed per unit of time in the HS compared with the HF diet. Supplementation with SC improved ADF digestibility (P = 0.038) and stimulated DM (P = 0.030) and NDF (P = 0.038) intakes, but had no effect on the MRT of solid digesta. The absence of any significant diet x SC interaction supports the strategy of using SC to stimulate cellulose digestion and improve the nutritional status of horses under both HF and HS diets.  相似文献   

10.
A bacterial marker can be used to determine the portion of fecal N that is of bacterial origin, as well as the effect of dietary factors on the bacterial N in feces of the dog. Two experiments were conducted to determine the efficacy of diaminopimelic acid (DAPA) and purines as bacterial markers in dogs. In Exp. 1, five adult female dogs were fed the same commercial diet. In Exp. 2, 50 dogs were fed one of four test diets (as-fed basis): a prebiotic-free control or diets containing either 1% chicory, 1% mannanoligosaccharide (MOS), or 1% chicory plus 1% MOS. Fresh feces were collected in both experiments and used to isolate a bacteria-rich sample (BRS) by differential centrifugation. In Exp. 1, the BRS had a N:purine ratio of 0.66 and N:DAPA ratio of 18.9. The CV for the N:purine ratio (20.7%) was much higher than that for the N:DAPA ratio (6.1%), indicating that DAPA resulted in a less variable estimate of fecal bacterial N. Using either marker, approximately 50% of the fecal N was estimated to be of bacterial origin. In Exp. 2, the N:DAPA ratio of the BRS did not differ (P = 0.14) among treatments. The BRS from dogs fed prebiotic-containing diets had treatment averages for N:DAPA ratios ranging from 16.9 to 18.5, whereas BRS from dogs fed the control diet had a ratio of 15.9. Averaged across all dogs, approximately 46% of fecal N was of bacterial origin. When calculating fecal bacterial concentrations using the average N:DAPA ratio for all dogs, little difference existed in the estimation compared with using individual values. The value resulting from use of the average ratio was approximately 13% higher than when using the individual ratios for dogs fed the control diet, which was due to the lower N:DAPA ratio for dogs fed the control diet compared with dogs fed the other treatments. Based on the consistency of the N:DAPA ratio of the BRS, DAPA seems to be a suitable marker for estimation of bacterial N in the feces of dogs.  相似文献   

11.
Tarentaise heifers fitted with a rumen cannula (539 +/- 7.5 and 487 +/- 15.7 kg avg initial BW in Exp. 1 and 2, respectively) were used in two Latin square metabolism experiments having 2 x 2 factorial treatment arrangements to determine the effects of supplementation with Aspergillus oryzae fermentation extract (AO) or laidlomycin propionate (LP) on intake, digestion, and digestive characteristics of Neotyphodium coenophialum-infected (IF) or uninfected (FF) tall fescue (Festuca arundinacea) hay diets consumed ad libitum. Heifers were housed in individual stanchions in a metabolism facility with ambient temperatures controlled to range between 26.7 and 32.2 degrees C daily. Total feces and urine were collected for 5 d following a 21-d dietary adaptation period. In situ DM and NDF disappearance and ruminal fermentation characteristics were also determined. In Exp. 1, DMI was 24% greater (P < 0.01) by heifers offered FF than by those offered IF (6.7 vs 5.4 kg/d). Heifers fed 2 g/d AO tended (P = 0.09) to consume 4% more DM than those fed a diet without AO. Degradable DM and NDF fractions of IF were greater (P < 0.01) than those of FF, but AO supplementation did not affect situ disappearance (P > or = 0.42). In Exp. 2, DMI was 18.9% greater (P < 0.01) by heifers offered FF than by those offered IF (6.6 vs 5.5 kg/d). Heifers fed LP (50 mg/d) consumed 10.6% less (P < 0.05) DM than those not fed LP (5.7 vs 6/5 kg/d). Digestibility of NDF tended to be greater (P = 0.08) and digestibility of ADF was greater (P < 0.05) from FF than from IF. Conversely, apparent N absorption (%) was greater (P < 0.05) from IF than from FF. Heifers fed LP had lower (P < 0.05) ADF digestibility than those not fed LP. In situ degradable DM and NDF fractions were greater (P < 0.01) from IF than from FF. Diets supplemented with LP had higher (P < 0.01) indigestible DM and NDF fractions than those without LP. Propionic acid and total VFA concentrations were greater (P < 0.05) from heifers offered FF than from those offered IF and from heifers fed LP than from those not fed LP. Therefore, it appears the major effect of N. coenophialum was a reduction in forage intake and total-tract fiber digestibility in certain situations. Response to the feed additives was similar whether heifers were offered IF or FF and no evidence was apparent that either additive would improve performance substantially by animals consuming low-quality fescue hay diets.  相似文献   

12.
Four ruminally and duodenally cannulated steers (703.4 +/- 41 kg initial BW) were used in a 4 x 4 Latin square to evaluate the effects of field pea inclusion level on intake and site of digestion in beef steers fed medium-concentrate diets. Steers were offered feed ad libitum at 0700 and 1900 daily and were allowed free access to water. Diets consisted of 45% grass hay and 55% by-products based concentrate mixture and were formulated to contain a minimum of 12% CP (DM basis). Treatments consisted of (DM basis) 1) control, no pea; 2) 15% pea; 3) 30% pea; and 4) 45% pea in the total diet, with pea replacing wheat middlings, soybean hulls, and barley malt sprouts in the concentrate mixture. Experimental periods consisted of a 9-d dietary adjustment period followed by a 5-d collection period. Grass hay was incubated in situ, beginning on d 10, for 0, 2, 5, 9, 14, 24, 36, 72, and 98 h; and field pea and soybean hulls for 0, 2, 5, 9, 14, 24, 36, 48, and 72 h. Total DMI (15.0, 13.5, 14.1, 13.5 +/- 0.65 kg/d) and OM intake (13.4, 12.0, 12.6, 12.0 +/- 0.58 kg/d) decreased linearly (P = 0.10) with field pea inclusion. Apparent ruminal (17.5, 12.0, 0.6, 6.5 +/- 4.31%) and true ruminal CP digestibility (53.5, 48.7, 37.8, 46.2 +/- 3.83) decreased linearly (P < 0.10) with increasing field pea. Neutral detergent fiber intake (8.9, 7.9, 7.8, 7.0 +/- 0.3 kg/d) and fecal NDF output (3.1, 2.9, 2.6, 2.3 +/- 0.2 k/d) decreased linearly (P < 0.03) with increasing field pea. No effects were observed for microbial efficiency or total-tract digestibility of OM, CP, NDF, and ADF (P > or = 0.16). In situ DM and NDF disappearance rates of grass hay and soybean hulls decreased linearly (P < 0.05) with increasing field pea. Field pea in situ DM disappearance rate responded quadratically (P < 0.01; 5.9, 8.4, 5.5, and 4.9 +/- 0.52%/h, for 0, 15, 30, and 45% field pea level, respectively). Rate of in situ CP disappearance of grass hay decreased linearly (P < 0.01) with increasing field pea level. Field pea is a suitable ingredient for beef cattle consuming medium-concentrate diets, and the inclusion of up to 45% pea in by-products-based medium-concentrate growing diets decreased DMI, increased dietary UIP, and did not alter OM, NDF, or ADF digestibility.  相似文献   

13.
An experiment was done to determine manure output, N and P excretion, and apparent digestibilities of AA, CP, P, and DM in growing pigs fed barley-based diets containing micronized or raw peas with or without supplementation with enzyme containing primarily beta-glucanase and phytase (Biogal S+). Eight barrows (21.5 +/- 1.2 kg of initial BW) fitted with T-cannulas at the distal ileum were used in a 40-d trial and housed in metabolism cages. Pigs were assigned in a replicated 4 x 4 Latin square design to 4 experimental diets: 1) barley-raw peas control (BRP), 2) barley-micronized peas (BMP), 3) BRP plus enzyme, and 4) BMP plus enzyme (BMP+E). Pigs received 2.6 times maintenance energy requirements based on BW at the beginning of each experimental period. During each experimental period, pigs were acclimatized to their respective diets for 5 d followed by a 3-d period of total fecal and urine collection and another 2-d period of ileal digesta collection. Samples were analyzed for DM, AA (diets and digesta only), N, and P. Wet fecal output of BRP plus enzyme-fed pigs tended to be lower (P = 0.07) than the amount produced by BMP-fed pigs. The amounts of dry feces and urine produced were not different among treatments (P > 0.10). Supplementing the BRP and BMP diet with enzyme increased (P = 0.002) the daily P retained per pig. Pigs fed the enzyme-supplemented diets tended to have lower (P = 0.06) fecal P excretion and greater urinary P excretion (P = 0.001) compared with pigs fed the nonsupplemented diets, but total P excretion was not influenced by diet (P > 0.10). Pigs fed the BMP+E diet retained more (P = 0.006) N per day than pigs fed the BMP diet. However, N excretion was not influenced by dietary treatment (P > 0.10), although BMP+E-fed pigs excreted 13.2% less N in the feces compared with those fed the nonenzyme supplemented controls. Inclusion of micronized peas with or without enzyme supplementation did not affect urinary or fecal N excretion (P > 0.10) compared with the BRP. Dietary treatment had no effect (P > 0.10) on ileal or fecal DM or CP digestibilities. Apparent ileal digestibilities of AA were usually lower (P < 0.05) in the BRP diet compared with the other diets. Enzyme supplementation improved P digestibility at the ileal and fecal level. The current results indicate that utilizing micronized peas in barley-based pig grower diets enhances P retention.  相似文献   

14.
This experiment aimed at evaluating the effects of including the enzyme, β-mannanase, in dog (Canis lupus familiaris) diets based on either poultry (Gallus gallus domesticus) by-product meal (PBM) or soybean [Glycine max (L.) Merr.] Meal (SBM). The second objective was to evaluate 3 methods for determining energy and nutrient digestibility values in diets fed to dogs: total fecal collection (TFC) and use of aia or crude fiber (CF) as a marker. Eight dogs were allotted to a replicated latin square (4 by 4) design. There were 2 diets based on PBM as the major protein source and 2 diets based on SBM as the major protein source. Within each protein source, 1 diet contained no β-mannanase and 1 diet contained 0.01% β-mannanase. Diets were fed for an adaptation period of 5 d followed by 5 d of TFC. Fecal score (1 = watery feces to 5 = dry, hard pellets), pH, DM, and fecal volume were determined. The apparent total tract digestibility (ATTD) of DM, OM, CP, ether extract (EE), N-free extract (NFE), and GE, and ME content were calculated using the methods of TFC, AIA, and CF. Data were analyzed as a 2 by 2 by 3 split-split-plot design (β-mannanase, protein source, and digestibility calculation procedure). There were interactions between protein source and β-mannanase (P < 0.05). Supplementation of β-mannanase increased ATTD of nutrients and energy and ME (+ 195.3 kcal/kg) and also reduced fecal production in the diet with SBM, but not in the diet that contained PBM. There was an interaction between digestibility calculation procedure and protein source (P < 0.05). The use of AIA overestimated ATTD of the diets containing PBM, but digestibility values estimated based on TFC and CF were not different. Dogs fed diets containing SBM produced more feces with greater moisture content and lower pH compared with dogs fed the PBM diet (P < 0.05). Addition of 0.01% β-mannanase increased (P < 0.05) the digestibility and ME content of the diets containing SBM, but did not improve (P > 0.05) fecal texture. Results indicated that values for ATTD of energy and nutrients in diets containing sbm are not different if they are calculated based on TFC, AIA, or CF, but use of AIA may result in an overestimation of values for ATTD of energy and nutrients in diets containing PBM.  相似文献   

15.
Six ruminally cannulated beef steers were used in a 6 x 6 Latin square experiment with a 3 x 2 factorial arrangement of treatments to evaluate the effects of barley supplementation (BS; 10, 30 or 50% of diet DM) and ruminal buffer (RB; Na sesquicarbonate at 0 or 4% of BS DM) addition to bromegrass hay-based diets on digestion. When early- (boot) and late- (full maturity) havested bromegrass and wheat straw substrates were incubated in situ, no interactions (P greater than .10) involving substrate with dietary BS or RB were observed, indicating that forages differing in fermentability responded similarly to different ruminal environments. Averaged across substrates, RB had no effect with 10% BS and a positive effect with 30% BS, but a negative effect with 50% BS diets (BS x RB, quadratic; P less than .05) for in situ DM and NDF disappearance for 18 and 24 h of incubation and for rate of disappearance of potentially degraded DM and NDF. Intakes of DM and digested DM were greater (P less than .01) for RB diets; however, RB had no effect (P greater than .10) on total tract DM and NDF digestibility. Intake and digestibility of DM increased linearly (P less than .01), whereas NDF digestibility decreased linearly (P less than .01) as BS percentage was increased in the diet. Sixty beef steers (avg initial wt 302 kg) were fed the same dietary treatments in a growth experiment. A numerical improvement in DM intake (P = .20) and ADG (P = .06) was observed when RB was provided with the 50% BS diet. Results of these experiments indicate that RB may moderate negative effects occurring on ruminal fiber digestion when grains are used to supplement forage-based diets; however, improvements in ruminal digestion were not translated effectively to improved animal productivity.  相似文献   

16.
Our objective was to measure ruminal fermentation characteristics and site and extent of nutrient digestion in sheep limit-fed an 81.6% (DM basis) concentrate diet supplemented with increasing levels of soybean oil. Eight white-faced wether lambs (39.9+/-3.0 kg BW) fitted with ruminal, duodenal, and ileal cannulas were used in a replicated 4 x 4 Latin square experiment. Diets were formulated to contain 15.0% CP (DM basis) and included bromegrass hay (18.4%), cracked corn, soybean oil, corn gluten meal, urea, and limestone. Soybean oil was added to diets at 0, 3.2, 6.3, and 9.4% of dietary DM. The diet was limit-fed at 1.4% of BW. After 14 d of dietary adaptation, Cr2O3 (2.5 g) was dosed at each feeding for 7 d followed by ruminal, duodenal, ileal, and fecal sample collections for 3 d. Digestibilities of OM, starch, NDF, and N were not affected (P = 0.13 to 0.95) by increasing dietary soybean oil level. Means for true ruminal (percentage of intake), lower-tract (percentage entering the duodenum), and total-tract (percentage of intake) digestibility for each nutrient were (mean+/-SEM): OM = 50.7+/-4.66%, 71.6+/-2.58%, and 82.7+/-0.93%; starch = 92.0+/-1.94%, 96.1+/-0.70%, and 99.8+/-0.05%; NDF = 36.7+/-6.75%, 50.9+/-7.58%, and 71.7+/-1.93%; and N = 31.6+/-9.93%, 84.1+/-1.50%, and 81.0+/-1.10%, respectively. Total VFA concentration was greatest in sheep fed 6.3% soybean oil and least in sheep fed 9.4% soybean oil (cubic, P = 0.01). Duodenal flow of fatty acids from the diet and those metabolized within the rumen increased (linear, P < 0.001) with increasing dietary soybean oil level. Ileal flow of 16:0, 17:0, 18:0, 18:1trans, and 18:1cis-9 fatty acids increased (P < or = 0.04) with increasing dietary soybean oil level. Apparent small intestinal disappearance of 18:0 decreased (linear, P = 0.004) as dietary soybean oil increased, and with 9.4% dietary soybean oil, nearly half the duodenal 18:0 was observed at the ileum; thus, the true energy value of the soybean oil decreased with increasing oil supplementation. We conclude that supplementation of a high-concentrate diet with increasing amounts of soybean oil in limit-fed sheep resulted in a trade off between loss of potential dietary energy from the fat and gain of important PUFA and biohydrogenation intermediates, but without a marked influence on digestibility of other important macronutrients.  相似文献   

17.
Weanling pigs with mean initial BW of 6.04 kg (Exp.1) and 5.65 kg (Exp. 2) and mean age at weaning of 18.2 d (Exp. 1) and 17.7 d (Exp. 2) were used in two 5-wk experiments (Exp. 1, n = 180; Exp. 2, n = 300) to evaluate the effects of an organic acid blend (Acid LAC, Kemin Americas Inc., Des Moines, IA) and an inorganic/organic acid blend (Kem-Gest, Kemin Americas Inc.) on weanling pig growth performance and microbial shedding. In Exp. 1, the 5 dietary treatments were 1) negative control, 2) diet 1 + 55 ppm carbadox, 3) diet 1 + 0.4% Acid LAC, 4) diet 1 + 0.2% Kem-Gest, 5) diet 1 + 0.4% Acid LAC and 0.2% Kem-Gest. In Exp. 2, the 6 dietary treatments were diets 1 through 4 corresponding to Exp. 1, plus 5) sequence 1: 0.4% Acid LAC for 7 d followed by 0.2% Kem-Gest for 28 d, and 6) sequence 2: 0.2% Kem-Gest for 7 d followed by 0.4% Acid LAC for 28 d. Pigs were housed at 6 (Exp. 1) or 10 (Exp. 2) pigs/pen. Treatments were fed throughout the experiment in 3 phases: d 0 to 7, d 7 to 21, and d 21 to 35. In Exp. 1, there were no differences (P > 0.05) in ADG, ADFI, or G:F among the dietary treatments at any time during the study. In Exp. 2, throughout the study, pigs fed carbadox (diet 2) and sequence 1 (diet 5) diets had the greatest ADG (d 0 to 35; 262, 294, 257, 257, 292, and 261 g/d, diets 1 through 6, respectively; P < 0.05), greater ADFI than all other acid treatments (P < 0.05), and tended to have greater ADFI than diet 1 (P < 0.10). Fecal pH, Escherichia coli concentrations, and Salmonella presence were determined at d 6, 20, and 34 for Exp. 1, and on d 32 for Exp. 2. For both experiments, there was no effect of treatment on the presence of fecal Salmonella (P > 0.10) at any sampling time. In Exp. 1, fecal E. coli concentrations for pigs fed the carbadox (P < 0.05) diet were greater than for pigs fed the combination diet with 0.4% Acid LAC and 0.2% Kem-Gest on d 34, and the pigs fed the negative control diet tended (P < 0.10) to have greater fecal E. coli concentrations than those fed the combination diet on d 34. In Exp. 2, fecal pH of pigs fed sequence 1 tended to be greater than fecal pH of pigs fed diet 1, diet 4, or sequence 2 (P < 0.10), but there was no dietary effect on fecal E. coli. In Exp. 1, growth performance of pigs fed the Acid LAC and Kem-Gest diets was similar to each other and to that of the carbadox-fed pigs. Adding the combination of 0.4% Acid LAC and 0.2% Kem-Gest to nursery pig diets reduced ADFI and pig growth rate. In Exp. 2, pigs fed the acid sequence of Acid LAC-Kem-Gest had similar growth performance to pigs fed carbadox, and this novel dietary acid sequence may have merit as a replacement for antibiotics in the nursery phase.  相似文献   

18.
Three experiments were conducted to evaluate the effects of feeding dietary concentrations of organic Zn as a Zn-polysaccharide (Quali Tech Inc., Chaska, MN) or as a Zn-proteinate (Alltech Inc., Nicholasville, KY) on growth performance, plasma concentrations, and excretion in nursery pigs compared with pigs fed 2,000 ppm inorganic Zn as ZnO. Experiments 1 and 2 were growth experiments, and Exp. 3 was a balance experiment, and they used 306, 98, and 20 crossbred pigs, respectively. Initially, pigs averaged 17 d of age and 5.2 kg BW in Exp. 1 and 2, and 31 d of age and 11.2 kg BW in Exp. 3. The basal diets for Exp. 1, 2, and 3 contained 165 ppm supplemental Zn as ZnSO4 (as-fed basis), which was supplied from the premix. In Exp. 1, the Phase 1 (d 1 to 14) basal diet was supplemented with 0, 125, 250, 375, or 500 ppm Zn as Zn-polysaccharide (as-fed basis) or 2,000 ppm Zn as ZnO (as-fed basis). All pigs were then fed the same Phase 2 (d 15 to 28) and Phase 3 (d 29 to 42) diets. In Exp. 2, both the Phase 1 and 2 basal diets were supplemented with 0, 50, 100, 200, 400, or 800 ppm Zn as Zn-proteinate (as-fed basis) or 2,000 ppm Zn as ZnO (as-fed basis). For the 28-d Exp. 3, the Phase 2 basal diet was supplemented with 0, 200, or 400 ppm Zn as Zn-proteinate, or 2,000 ppm Zn as ZnO (as-fed basis). All diets were fed in meal form. In Exp. 1, 2, and 3, pigs were bled on d 14, 28, or 27, respectively, to determine plasma Zn and Cu concentrations. For all three experiments, there were no overall treatment differences in ADG, ADFI, or G:F (P = 0.15, 0.22, and 0.45, respectively). However, during wk 1 of Exp. 1, pigs fed 2,000 ppm Zn as ZnO had greater (P < or = 0.05) ADG and G:F than pigs fed the basal diet. In all experiments, pigs fed a diet containing 2,000 ppm Zn as ZnO had higher plasma Zn concentrations (P < 0.10) than pigs fed the basal diet. In Exp. 1 and 3, pigs fed 2,000 ppm Zn as ZnO had higher fecal Zn concentrations (P < 0.01) than pigs fed the other dietary Zn treatments. In conclusion, organic Zn either as a polysaccharide or a proteinate had no effect on growth performance at lower inclusion rates; however, feeding lower concentrations of organic Zn greatly decreased the amount of Zn excreted.  相似文献   

19.
Two experiments with growing pigs were conducted to determine the effects of dietary P and Ca level, phytase supplementation, and ileal pectin infusion on ileal and fecal P and Ca balance, chemical composition of fecal mixed bacterial mass (MBM), and bacterial metabolic activity. Pigs (initial BW = 30 kg) were fitted with simple T-cannulas at the distal ileum. They were fed a low-P corn-soybean meal control diet (3 g of P/kg) or the control diet supplemented with monocalcium phosphate (MCP; 7 g of P/kg; Exp. 1) or 1,000 FTU phytase/kg (Exp. 2). The daily infusion treatments consisted of 60 g of pectin dissolved in 1.8 L of demineralized water or 1.8 L of demineralized water as the control infusion, infused via the ileal cannula. In each experiment, 8 barrows were assigned to 4 dietary treatments according to a double, incomplete 4 x 2 Latin square. The dietary treatments in Exp. 1 were the control (Con-) diet with water infusion; the control (Con+) diet with pectin infusion; the MCP diet with water infusion; and the MCP diet with pectin infusion. In Exp. 2, the pigs received the same Con- and Con+ treatments as in Exp. 1 and, in addition, the phytase-supplemented diet in combination with water or pectin infusion. After a 15-d adaptation period, feces were collected for 5 d followed by ileal digesta collection for 24 h. In Exp. 1, supplemental MCP increased (P 相似文献   

20.
Addition of fat to the diet of the equine is a popular method of increasing energy density of the diet while reducing feed intake. Reducing feed intake is of interest to race horse trainers because additional feed is seen as additional weight and, therefore, a hindrance to performance. Limited information is available regarding the interactions of fat with other dietary components, particularly fiber, in the equine digestive system. The effect of dietary fat on in vitro nutrient disappearance in equine cecal fluid was studied in Exp. 1 using a split-plot design within a 2 x 2 Latin square. Two ponies were fed alfalfa (ALF) alone or alfalfa plus 100 g/d corn oil. Five substrates were used to determine in vitro DM disappearance, OM disappearance, NDF disappearance, and total dietary fiber (TDF) disappearance. The substrates included: ALF, tall fescue (TF), red clover (RC), soybean hulls (SBH), and rolled oats (RO). Fat supplementation did not affect in vitro DM, OM, or NDF disappearance. Addition of fat to the diet increased (P < 0.05) the disappearance of NDF in RO. Among substrates, in vitro DM and OM disappearance were highest (P < 0.05) for RO, followed by SBH, ALF, RC, and TF. In vitro NDF and TDF disappearance were highest (P < 0.05) for SBH, followed by RO, ALF, RC, and TF. In Exp. 2, the effects of varying levels of fat on nutrient intake and total tract digestibility were examined using a 4 x 4 Latin square design. Four mature mares were fed a 60% forage-40% concentrate diet containing different concentrations of fat: 0% supplemental fat control (C); 5% supplemental corn oil (5% CO); 10% supplemental corn oil (10% CO); or 15% supplemental corn oil (15% CO). Treatment did not affect intake of the concentrate portion of the diet or CP, gross energy, or NDF intake. Mares consuming the C diet had the highest (P < 0.05) intake of alfalfa cubes, DM, and OM, followed by those on the 10, 5, and 15% CO treatments, respectively. Treatment did not affect nutrient digestibility. Mares consuming the 15% CO diet had the highest (P < 0.05) fat digestibility, whereas those consuming C had the lowest fat digestibility. Fat in the form of CO generally had little effect on in vitro and in vivo nutrient digestibilities in horses.  相似文献   

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