Effect of enzyme addition to wheat-, barley- and rye-based diets on nutrient digestibility and performance of laying hens

1. Laying hen performance, egg quality, intestinal viscosity and nutrient apparent digestibility were evaluated with respect to the main cereal used in the diet and dosage rate of a fungal beta-glucanase/xylanase enzyme complex. 2. Twelve diets were arranged factorially, with three soluble fibre cereals (SFC); 500 g/kg of wheat or barley or 350 g/kg of rye, and 4 enzyme concentrations (0, 250, 1250 and 2500 mg/kg). An additional control diet based on maize was also included. 3. The use of SFC in the diet instead of maize did not affect egg production or food efficiency, but hens fed on SFC diets exhibited a higher incidence of dirty eggs than hens fed on the maize diet (8-6 vs 4.6%; P<0.01). 4. Laying hens fed on enzyme-supplemented diets produced more eggs (2.1%; P<0.05) and had better food efficiency per dozen eggs (2.5%; P<005) than hens fed on non-supplemented diets. An excess of enzymes in the diet (10 times the recommended dose) did not produce any deleterious effect on laying hen productivity. 5. Enzyme supplementation (ES) reduced intestinal viscosity (P<0.001) and the incidence of dirty eggs (P<0.01). The reduction in viscosity was more pronounced in barley than in wheat or rye diets (P<0.05). 6. Apparent nutrient digestibility in SFC diets was higher with ES, including dry matter (3.1%; P=0.08), fat (4.4%; P<0.001), non-starch polysaccharides (83.3%; P<0.01) and AMEn (2.5%, P<0.01). 7. It is concluded that substitution of maize by SFC is facilitated by ES, especially with respect to egg production, food conversion efficiency and egg shell cleanliness. An excess of enzymes did not produce any deleterious effect on nutrient digestibility or performance of laying hens.     

Nutrient intake, digestibility, and blood metabolites of goats fed diets containing processed jatropha meal

This study was conducted to record the ideal source and level of alkali treatment to treat jatropha meal (JM) and to determine the effect of inclusion of variously processed JM (pJM) on nutrient intake, digestibility, blood metabolites and hormonal status in goats. The JM was treated with 10 g/kg sodium chloride and 5 g/kg calcium hydroxide. The content of phorbol ester and hemagglutination (HA) activity of JM and pJM were assessed. A feeding trial for 90 days was conducted in short-haired multipurpose goats (n?=?15; five per group). The experimental animals were offered oat (Avena sativa) straw ad libitum throughout the experimental period of 90 days. Each group was assigned to one of the three diets, viz. R₁—soybean meal, R₂—sodium chloride (10 g/kg dry matter, DM), and R₃—calcium hydroxide (5 g/kg DM), with pJM substituting 250 g/kg DM of crude protein (CP) of control (R₁). At the end of the feeding period, digestion trial of 7 days was conducted. Blood samples were collected at the end of the experimental period to assess the blood metabolites and hormonal status. The phorbol ester and HA activity were reduced considerably in pJM. The intake of DM, organic matter, CP, and nitrogen-free extract were comparable among all the groups. However, the intake of ether extract was significantly higher in pJM-fed groups. The hemoglobin, packed cell volume, serum urea, triiodothyronine and testosterone contents decreased in R₂ and R₃ as compared to R₁. Concentration of glucose and activity of serum glutamic pyruvic transaminase and lactate dehydrogenase increased (P?<?0.01) in goats fed pJM. It was concluded that phorbol ester content and HA activity markedly decreased by processing JM with sodium chloride and calcium hydroxide. However, they were not reduced to the levels of safe feeding, as reflected in unusual values of blood metabolites among the experimental animals.     

高油脂日粮中添加外源性乳化剂对肉鸡饲料养分利用率的影响

选用48只体重一致的、健康的36日龄的爱拔益加(Arbor Acre)雄性肉鸡,随机分成6个处理,每个处理4个重复,研究等能和等蛋白情况下,在高油脂含量日粮中添加不同剂量(0、400、530、660、800g/t)的外源性乳化剂对肉鸡饲料营养物质表观和真实代谢率的影响。结果表明:高油脂饲料中添加不同水平的外源性乳化剂不同程度地提高了能量、粗脂肪和干物质的表观和真实代谢率以及表观和真实代谢能,并且随着乳化剂添加水平的提高而呈上升的趋势。其中800g/t乳化剂水平下,能量、粗脂肪的真实代谢率、真实代谢能都提高值最大,添加400g/t乳化剂处理组和对照组差异不显著。     

Effects of essential oils,yeast culture and malate on rumen fermentation,blood metabolites,growth performance and nutrient digestibility of Baluchi lambs fed high‐concentrate diets

The experiment was conducted to evaluate the effects of dietary supplementation with a mixture of essential oils (MEO), yeast culture (YC) and malate on performance, nutrient digestion, rumen fermentation and blood metabolites of lambs fed high‐concentrate growing diets. For this purpose, twenty Baluchi lambs (17.3 ± 0.5 kg body weight and 3 months old) were randomly assigned to four dietary treatments in a completely randomized design with five lambs per treatment. The treatment groups were as follows: (i) control: basal diet without any additive, (ii) basal diet plus 400 mg/day MEO (thymol, carvacrol, eugenol, limonene and cinnamaldehyde), (iii) basal diet with 4 g/day YC and (iv) basal diet plus 4 g/day malate. No differences between the dietary treatments were observed in dry matter intake, average daily gain or feed conversion ratio (p > 0.05). Compared with control and malate treatment, lambs fed MEO and YC had an improved crude protein digestibility (p < 0.05). Yeast culture significantly increased (p > 0.05) cell wall digestibility compared to the other treatments. No differences were observed between treatments with respect to nitrogen balance or ruminal pH and ammonia concentrations (p > 0.05). No differences were observed between treatments with respect to ruminal total volatile fatty acid concentration and molar proportions of acetate, butyrate and valerate. Molar proportion of propionate was higher (p < 0.05) for YC and malate compared to control and MEO. Plasma glucose concentration was higher (p < 0.05) in lambs fed YC and malate than in lambs fed the control or the MEO diet. Blood concentration of triglycerides significantly decreased when feeding the MEO and YC diets (p < 0.05). It was concluded that YC may be more useful as a feed additive for manipulation of rumen fermentation in lambs fed with high‐concentrate diets than MEO and malate, because YC enhanced crude protein and cell wall digestibility, ruminal molar proportion of propionate and plasma glucose concentration.     

Growth performance,nutrient digestibility,and fecal microbial composition of weaned pigs fed multi-enzyme supplemented diets

A study determined the effects of supplementing corn-based diets for weaned pigs with multi-enzymes on growth performance, apparent total tract digestibility (ATTD) of nutrients, fecal score, and fecal microbial composition. A total of 132 pigs (initial body weight = 7.23 kg) that had been weaned at 21 d of age and fed a drug-free nursery diet for 7 d were housed in 33 pens of 4 barrows or gilts, blocked by body weight and gender, and fed 3 experimental diets at 11 pens per diet. The diets were corn-based diet without or with multi-enzyme A or B. Multi-enzyme A supplied 4,000 U of xylanase, 150 U of β-glucanase, 3,500 U of protease, and 1,500 U of amylase per kilogram of diet. Multi-enzyme B was the same as multi-enzyme A except that it supplied amylase at 150 U/kg, and that its source of amylase was different from that of multi-enzyme A. All diets contained phytase at 1,000 U/kg. The diets were fed for 35 d in 2 phases; phase 1 for the first 14 d and phase 2 for the last 21 d of the trial. Fecal score was determined daily during the first 7 d of the trial. Fecal samples were collected from rectum of 1 pig per pen on days 2, 7, 14, and 35 of the trial for determining bacterial composition. Also, fresh fecal samples were collected from each pen on days 41 and 42 to determine ATTD of nutrients. Multi-enzyme B increased (P < 0.05) average daily gain (ADG) for phases 1 and 2. For the overall study period, multi-enzyme B increased (P < 0.05) ADG from 262 to 313 g, and average daily feed intake (ADFI) from 419 to 504 g. Multi-enzyme A increased (P < 0.05) overall ADG from 262 to 290 g, but did not affect ADFI. Multi-enzyme A or B did not affect ATTD of gross energy, but increased (P < 0.05) the ATTD of ether extract from 30% to 36% or 37%, respectively. Multi-enzyme A did not affect fecal score; however, multi-enzyme B tended to decrease (P = 0.09) fecal score, implying that it tended to decrease diarrhea. Firmicutes were the most abundant phylum of fecal bacteria (its relative abundance ranged from 58% to 72%). Bacteroidetes and Actinobacteria were the 2nd and 3rd most abundant phyla of fecal bacteria. Neither multi-enzyme affected fecal bacterial composition. In conclusion, the addition of multi-enzyme A or B to phytase-supplemented corn-based diet for weaned pigs can improve their growth performance and fat digestibility. However, multi-enzyme B was more effective than multi-enzyme A in terms of improving the growth performance of weaned pigs fed corn-based diet.     

Effect of grain processing and silage on microbial protein synthesis and nutrient digestibility in beef cattle fed barley-based diets

Effects of the extent of grain processing and the percentage of silage in barley-based feedlot diets on microbial protein synthesis and nutrient digestibility were evaluated using four steers (initial BW of 442 +/- 15 kg) with ruminal and duodenal cannulas. The experiment was a 4 x 4 Latin square with four periods of 21 d each. Dietary treatments were arranged as a 2 x 2 factorial with two levels of barley silage (20 and 5% DM basis) and two degrees of barley grain processing (coarsely and flatly steamrolled to a processing index [PI] of 86 and 61%, respectively). The PI was quantified as the volume weight of the barley grain after processing, expressed as a percentage of the volume weight prior to processing. Digest a flow (Yb) and microbial (15N) markers were continuously infused into the rumen for a period of 13 d. Ruminal, duodenal, and fecal samples were collected at various times over the last 6 d of marker infusion. Diurnal ruminal pH was measured for 48 h. Intake of DM averaged 1.8% of BW, and was not different among the dietary treatments (P > 0.10). Ruminal starch digestibility was higher (P < 0.05) for the more extensively processed grain and tended (P < 0.10) to be highest when the more extensively processed grain was combined with 5% barley silage. In contrast, ruminal fiber digestibility for the 5% silage diets was reduced (P < 0.05) when the grain was more extensively processed. There was, however, no effect of grain processing on ruminal OM digestibility (P > 0.10), and hence, no inhibitory effect on microbial N flow to the intestine (P > 0.10). There was also no effect of the level of silage on microbial N flow (P > 0.10), but there was a tendency for improved efficiency of microbial protein synthesis for the 20% silage diets (P = 0.072). Ruminal escape of nonmicrobial N (P = 0.003) was greater, and thus, protein flow to the intestine was greater for the 5% silage diets. Diurnal ruminal pH was lower (P < 0.05) for 11 of the 24 hourly time points in steers fed the 5% silage diets than those fed the 20% silage diets. In conclusion, barley grain rolled to a PI of 86 to 61% and combined with 20 and 5% barley silage had little effect on microbial protein supply. Microbial protein supply was not inhibited when the barley grain was extensively processed (PI of 61%) and the silage was limited to only 5% of the diet DM, but feed intake of steers in this study was lower than would be expected in the feedlot.     

Effects of exogenous enzyme supplementation to corn- and soybean meal-based or complex diets on growth performance, nutrient digestibility, and blood metabolites in growing pigs

Two experiments were conducted to determine the effects of dietary supplementation of exogenous enzymes on growth performance, apparent total tract digestibility (ATTD) of energy and nutrients, blood metabolites, fecal VFA, and fecal ammonia-N in growing pigs (Sus scrofa) fed a corn (Zea mays L.)- and soybean [Glycine max (L.) Merr.] meal (SBM)-based diet. In Exp. 1, 240 growing barrows (initial BW: 55.6 ± 0.9 kg) were randomly allotted to 5 treatments on the basis of BW. There were 4 replicates in each treatment with 12 pigs per replicate. The 5 treatments consisted of a corn-SBM-based control diet and 4 additional diets were similar to the control diet, with the exception that 0.05% β-mannanase (M), α-amylase + β-mannanase (AM), β-mannanase + protease (MPr), or α-amylase + β-mannanase + protease (AMP) was added to the diets, which were fed for 28 d. Pigs fed the AM, MPr, or AMP diet had greater (P < 0.05) ADG than pigs fed the control diet. Pigs fed the AMP diet also had greater (P < 0.05) ADG than pigs fed the M, AM, or MPr diet. Pigs fed the AMP diet had greater (P < 0.05) G:F than pigs fed the control diet. The G:F of the pigs fed the M, AM, or MPr diet were not different (P > 0.05) from the G:F in pigs fed the AMP or control diet. The ADFI, ATTD of nutrients, blood metabolites, and fecal VFA and ammonia-N concentrations were not different among treatments. In Exp. 2, 192 growing barrows (initial BW: 56.9 ± 1.0 kg) were allotted to 4 treatments. There were 4 replicates in each treatment with 12 pigs per replicate. Pigs were fed a corn-SBM-based diet (CSD) or a complex diet (CD) that contained corn, SBM, 3% rapeseed (Brassica napus L.) meal, 3% copra (Cocos nucifera L.) meal, and 3% palm (Elaeis guineensis Jacq.) kernel meal. Each diet was prepared without exogenous enzymes or with 0.05% AMP and all diets were fed for 28 d. The ADG and G:F of pigs fed the CSD were greater (P < 0.05) than pigs fed the CD. However, the type of diet had no effect on the ATTD of nutrients, blood metabolites, or fecal VFA and ammonia-N, and there was no diet × enzyme interaction for any of the measured variables. Supplementation of diets with exogenous enzymes resulted in greater (P < 0.05) ADG, G:F, ATTD of DM, GE, and CP, and blood urea nitrogen (BUN) concentration. These results indicate that supplementation of 0.05% of AMP enzymes to a corn-SBM diet or a complex diet may improve the performance of growing pigs.     

Lysocellin effects on growth performance, ruminal fermentation, nutrient digestibility and nitrogen metabolism in steers fed forage diets

Studies were conducted to determine the effects of lysocellin on growth performance and metabolism of steers fed forage-based diets. Treatments in all experiments consisted of 1) control, 2) 100 mg lysocellin/d, 3) 200 mg lysocellin/d and 4) 200 mg monensin/d. In each of two 90-d performance studies, 24 Hereford steers were individually fed greenchop (fungus-free tall fescue and Coastal and Tifton-44 bermudagrass) ad libitum and .91 kg/d of a corn-trace mineral salt supplement. In Exp. 1, tall fescue was fed from d 1 to 45 and bermudagrass from d 46 to 90. Bermudagrass was offered during d 1 to 45 and tall fescue during d 46 to 90 in Exp. 2. Lysocellin improved gain (Exp. 1, P less than .01) and feed conversion (Exp. 1 and 2 combined, P less than .05), decreased total VFA concentrations (P less than .05), increased molar proportions of propionate, isobutyrate and isovalerate (P less than .01), decreased molar proportions of acetate and butyrate (P less than .01) and lowered acetate:propionate (P less than .01). Two metabolism studies involving a total of 16 Hereford steers were conducted. Steers were fed tall fescue greenchop and .91 kg/d supplement for a 34-d adjustment period followed by a 5-d total collection period. Lysocellin increased N digestibility (P less than .01) and N retention (P less than .06) but did not (P greater than .05) affect DM, NDF or ADF digestibility. Data indicate that lysocellin results in major alterations in ruminal fermentation and can increase growth performance and N retention in steers fed forage-based diets.     

低蛋白和杂粕日粮对生长猪生产性能、养分消化、血液指标和猪舍氨气的影响

用50 kg左右的DLY生长猪196头,分4个处理(标准豆粕日粮、标准8%杂粕日粮及其相应低蛋白日粮),各处理日粮按NRC1998标准配制,可消化赖氨酸、苏氨酸、蛋+胱氨酸、色氨酸和异亮氨酸达到理想蛋白氨基酸比例和水平,研究低蛋白和杂粕日粮对猪生产性能、养分消化、血液指标和猪舍氨气的影响。结果表明,150~80 kg阶段标准豆粕和8%杂粕日粮粗蛋白质降低3个百分点,对猪的生产性能没有显著影响(P0.05);2蛋白质降低3个百分点显著降低日粮蛋白质表观消化率(P0.05);豆粕日粮赖氨酸、苏氨酸、蛋氨酸、缬氨酸等必需氨基酸表观消化率没有降低,杂粕日粮所有氨基酸表观消化率都显著降低(P0.05);对纤维、脂肪、灰分、钙和磷表观消化率也有不同程度影响;3低蛋白质日粮显著降低猪血浆尿素氮水平(P0.05);4低蛋白日粮能显著降低猪舍有害气体氨气浓度(P0.05)。     

Effects of beta-mannanase addition to corn-soybean meal diets on growth performance,carcass traits,and nutrient digestibility of weanling and growing-finishing pigs

Four experiments were conducted to determine the effects of adding a beta-mannanase preparation (Hemicell, ChemGen, Gaithersburg, MD) to corn-soybean meal-based diets on growth performance and nutrient digestibility of weanling and growing-finishing pigs. In Exp. 1, 156 weanling pigs (20 d, 6.27 kg BW) were allotted to four dietary treatments in a randomized complete block design. Treatments were a factorial arrangement of diet complexity (complex vs simple) and addition of 3-mannanase preparation (0 vs 0.05%). Pigs were fed in three dietary phases (Phase 1, d 0 to 14; Phase 2, d 14 to 28; and Phase 3, d 28 to 42). Pigs fed complex diets gained faster and were more efficient (P < 0.05) during Phase 1 compared with pigs fed simple diets. Overall, gain:feed ratio (G:F) tended to be improved (P < 0.10) for pigs fed complex diets and it was improved (P < 0.01) for those fed diets with beta-mannanase. In Exp. 2, 117 pigs (44 d, 13.62 kg BW) were allotted randomly to three dietary treatments. Dietary treatments were 1) a corn-soybean meal-based control, 2) the control diet with soybean oil added to increase metabolizable energy (ME) by 100 kcal/kg, and 3) the control diet with 0.05% beta-mannanase preparation. Beta-mannanase or soybean oil improved (P < 0.05) G:F compared with pigs fed the control diet. In Exp. 3, 60 pigs (22.5 kg BW) were allotted randomly to the three dietary treatments used in Exp. 2. Dietary treatments were fed in three phases (23 to 53 kg, 53 to 82 kg, and 82 to 109 kg with 0.95, 0.80, and 0.65% lysine, respectively). Overall, the addition of soybean oil tended to improve G:F (P < 0.10) compared with that of pigs fed the control diet, and G:F was similar (P > 0.54) for pigs fed diets with soybean oil or beta-mannanase. Also, addition of beta-mannanase increased ADG (P < 0.05) compared with that of pigs fed the control or soybean oil diets. There were no differences (P > or = 0.10) in longissimus muscle area or backfat; however, on a fat-free basis, pigs fed the diet with beta-mannanase had greater (P < 0.05) lean gain than pigs fed the control or soybean oil diets. In Exp. 4, 12 barrows (93 kg BW) were allotted randomly to one of the three dietary treatments used in Exp. 3. Addition of 3-mannanase had no effect (P > 0.10) on energy, nitrogen, phosphorus, or dry matter digestibility. These results suggest that beta-mannanase may improve growth performance in weanling and growing-finishing pigs but has minimal effects on nutrient digestibility.     

Growth performance, diet apparent digestibility, and plasma metabolite concentrations of barrows fed corn-soybean meal diets or low-protein, amino acid-supplemented diets at different feeding level

Two experiments, each with 36 barrows with high-lean-gain potential, were conducted to evaluate apparent nutrient digestibilities and performance and plasma metabolites of pigs fed corn-soybean meal diets (CONTROL) and low-protein diets. The low-protein diets were supplemented with crystalline lysine, threonine, tryptophan, and methionine either on an ideal protein basis (IDEAL) or in a pattern similar to that of the control diet (AACON). Amino acids were added on a true ileally digestible basis. The initial and final BW were, respectively, 31.5 and 82.3 kg in Exp. 1 and 32.7 and 57.1 kg in Exp. 2. In Exp. 1, the CONTROL and IDEAL diets were offered on an ad libitum basis or by feeding 90 or 80% of ad libitum intake. Pigs were fed for 55 d. In Exp. 2, the CONTROL, IDEAL, and AACON diets were offered on an ad libitum basis or by feeding 80% of the ad libitum intake. Pigs were fed for 27 d. Pigs fed the CONTROL diet had greater (P < 0.05) ADG and feed efficiency (G/F) than pigs fed the IDEAL (Exp. 1 and 2) and AACON diets (Exp. 2). As the level of feed intake decreased, ADG decreased (P < 0.05), but G/F tended to improve (P < 0.10) for pigs fed 90% of ad libitum in Exp. 1 and for pigs fed 80% of ad libitum in Exp. 2. In Exp. 1, the apparent total tract digestibilities of DM and energy were greater (P < 0.01) for pigs fed the IDEAL diet than for pigs fed the CONTROL diet. In Exp. 2, the apparent total tract digestibility of protein was greatest in pigs fed the CONTROL diet (P < 0.05) and was greater (P < 0.05) in pigs fed the AACON diet than in pigs fed the IDEAL diet. Plasma urea concentrations were lower in pigs fed the IDEAL diet than in pigs fed the CONTROL diet, regardless of feeding level. For pigs fed the CONTROL diet, plasma urea concentrations were lower when feed intake was 80% of ad libitum (diet level, P < 0.01). In summary, pigs fed the IDEAL and the AACON diets gained less and had lower plasma urea concentrations than pigs fed the CONTROL diet. Based on these data, it seems that the growth potential of pigs fed the IDEAL and AACON diets may have been limited by a deficiency of lysine, threonine, and(or) tryptophan and that the amino acid pattern(s) used was not ideal for these pigs.     

低蛋白日粮对育肥猪生产性能和养分消化率的影响

试验研究了低蛋白日粮对育肥猪生产性能和养分消化率的影响,试验选择初始体重为70kg的杜×大×长三元猪80头,采用单因子设计,分为对照组和试验组。对照组中日粮按照NRC(1998)营养需要量推荐配制,试验组在NRC推荐的日粮粗蛋白水平上降低3.1个百分点。试验结果表明:试验组日增重比对照组增加了85g,提高幅度为10.88%(P0.01);试验组料肉比比对照组降低了12.11%(P0.01);试验组单位增重成本比对照组节约了1.09元/kg(P0.01)。试验结果还表明:试验组氨基酸消化率均高于对照组,其中赖氨酸、苏氨酸和色氨酸消化率显著高于对照组(P0.01);蛋氨酸消化率极显著高于对照组(P0.05);粗脂肪和粗蛋白的消化率极显著高于试验组(P0.01);而血清尿素氮含量极显著低于对照组(P0.01)。从各指标的趋势上看,试验组的生长性能、养分消化率和经济效益均优于对照组。     

Nutrient digestibility and feedlot performance of lambs fed diets varying protein and energy contents

Thirty-six Thalli male growing lambs were used in a completely randomized design with 2 × 2 factorial arrangement of treatments to evaluate the effect of varying levels of energy and protein on nutrient intake, digestibility, weight gain, and gain to feed ratio. Four experimental diets, i.e., low energy–low protein (LE-LP), low energy–high protein (LE-HP), high energy–low protein (HE-LP), and high energy–high protein (HE-HP) were formulated. The low- and high-energy diets contained 2.3 and 2.7 MJ/kg dry matter (DM) with 12% and 14% of crude protein. The lambs were fed ad libitum. Dietary energy and protein levels and their interactions influenced the nutrient intake. Maximum dry matter intake was noted in animals fed LE-HP diet followed by LE-LP, HE-HP, and HE-LP diets. Digestibility of DM and N increased (P < 0.01) and that of neutral detergent fiber decreased (P < 0.01) linearly with increasing levels of dietary energy and protein. Digestibility of N was only affected by protein level and interaction between energy and protein levels. Average daily gain was higher (P < 0.01) in lambs fed HE-HP diet followed by LE-HP, LE-LP, and HE-LP diets. Dietary energy and protein levels and their interaction had significant effect (P < 0.01) on gain to feed ratio.     

苜蓿草粉对杜洛克生长猪生长性能和养分消化的影响

将48头体重相近的杜洛克生长猪随机分成4组(每组4个重复),研究苜蓿草粉对杜洛克生长猪生长性能和养分消化的影响。结果表明:5%和10%的替代率使得生长猪的日增重显著增加(分别为10.4%、6.28%);料肉比下降不显著(7.62%、9.97%);对猪日采食量的影响也不显著。饲喂苜蓿草粉后降低了养分的消化率,而5%、10%替代组与对照组差异不显著。20%替代组的生长性能显著下降(P<0.05),养分消化率极显著降低(P<0.01)。     

Effects of protein concentration and source on nutrient digestibility by mature steers limit-fed high-concentrate diets.

Five ruminally fistulated 3-yr-old mature Holstein steers (average BW 691+/-23 kg) were used in a 5 x 5 Latin square experiment with a 2 x 2 + 1 fact orial arrangement of treatments. Effects of protein concentration and protein source on nutrient digestibility, excretion of DM and fecal N, ruminal fluid volume and dilution rate, ruminal characteristics, and in situ DM disappearance of whole shelled corn, ground corn, and orchardgrass hay were measured in steers limit-fed high-concentrate diets at 1.5% of BW. A negative control basal diet (NC; 9% CP) was supplemented to achieve either 11 or 14% CP; supplemental CP was either from soybean meal (11 and 14% SBM) or a 50:50 ratio of CP from urea and soybean meal (11 and 14% U). Dry matter and OM digestibilities were 5% greater (P < .07) for steers fed the SBM diets than for those fed the U diets. Starch digestibility did not differ (P > .10) among steers fed any of the diets. Nitrogen source did not affect (P > .10) apparent N digestibility or fecal N excretion; however, steers fed the NC diet had the lowest (P < .10) apparent N digestibility compared with those fed all other diets. Ruminal fluid volume was lower (P < .06) when steers were fed the NC diet compared with all other diets; there were no differences (P > .74) among diets for ruminal fluid dilution rate. In general, ruminal ammonia N and VFA molar proportions were not affected by protein source or concentration. Although CP concentration affected (P < .06) in situ DM disappearance of ground corn, CP concentration did not (P > .48) affect total tract digestion of DM or OM. This indicates that CP concentration may have affected site of digestion, but not extent of digestion. When mature ruminants were limit-fed a corn-based diet to meet primarily a maintenance function, protein source and concentration had little effect on measures of nutrient digestion.     

Growth performance, gastrointestinal microbial activity, and nutrient digestibility in early-weaned pigs fed diets containing flaxseed and carbohydrase enzyme

The effects of ground flaxseed (FS) and a multicarbohydrase enzyme (C) supplement on piglet performance, gastrointestinal microbial activity, and nutrient digestibility were investigated in a 28-d trial. The enzyme supplement provided 500 units of pectinase, 50 units of cellulase, 400 units of mannanase, 1,200 units of xylanase, 450 units of glucanase, and 45 units of galactanase per kilogram of diet. Ninety-six pigs were weaned at 17 d of age (BW, 6.1 +/- 0.4 kg, mean +/- SD) and assigned to treatments based on a 2 x 2 factorial arrangement in a completely randomized design, with 6 pens per diet (4 pigs per pen). The diets contained wheat, barley, peas, soybean meal, and canola meal with 0 or 12% FS, and were fed without or with C. Flaxseed was included by changing the levels of the other ingredients to balance the diets for DE and nutrients. Diets had similar nutrient contents and met the NRC (1998) nutrient specifications, with the exception of DE, CP, and AA, which were 95, 94, and 97% of the NRC requirements, respectively. Diets were fed in a 2-phase feeding program (2 wk/phase). Feed intake and BW were measured weekly, and 1 pig per pen with a BW nearest the pen average was bled weekly to evaluate plasma urea nitrogen. On d 28, fresh fecal samples were collected from each pen and 1 pig per pen with a BW nearest the pen average was killed to evaluate intestinal microbial activity and nutrient digestibility. A dietary effect on piglet performance was observed only in wk 3, when the FS diets decreased (P = 0.005) ADG and G:F, tended to decrease (P = 0.070) ADFI, and increased (P = 0.027) plasma urea nitrogen. An interaction between FS and C was observed for ileal digesta viscosity (P = 0.045), such that C increased viscosity in the FS diet but had no effect in the non-FS diet. Flaxseed and C interacted to affect ileal ammonia content (P = 0.049), such that in the absence of FS, pigs fed the diet with C had lower ammonia than those on the diet without C. Flaxseed and C affected other ileal parameters independently. Pigs fed the FS diets had decreased (P = 0.003 to 0.033) anaerobic spore counts, organic acid, DM, CP, and nonstarch polysaccharide (NSP) digestibility compared with pigs fed the non-FS diets, whereas pigs fed the C-supplemented diets had greater (P = 0.009 to 0.061) lactobacilli counts, lactate, DM, and NSP digestibility than pigs fed the unsupplemented diets. In conclusion, FS reduced ileal microbial activity, nutrient digestibilities, and piglet performance in wk 3. The multicarbohydrase supplement increased ileal DM and NSP digestibilities as well as lactobacilli counts and lactate.     

Effect of high-oil corn on growth performance, diet digestibility, and energy content of finishing diets fed to beef cattle

Sixty crossbred beef steers (initial BW = 412 kg) were used in a 83-d finishing study to determine the effect of feeding dry rolled high-oil corn on performance and total-tract digestibility of finishing diets. Steers were allotted by weight to the following dietary treatments: 1) control corn (C; 82% normal corn, 12% triticale silage), 2) high-oil corn (HO; 82% high-oil corn, 12% silage), and 3) high-oil corn formulated to be isocaloric to C (ISO; 74% high-oil corn, 20% silage). Total lipid content was 4.9% (DM basis) for normal corn and 7.0% for high-oil corn. Steers were individually fed using electronic gates. Quantity of feed offered and refused was recorded daily. Fecal samples were collected on d 63 to 66 of the trial to determine digestibility. Chromic oxide was fed as an indigestible marker for 7 d before fecal collection began. Planned contrasts of HO vs C and ISO vs C were used to assess treatment differences. Dry matter intake was greater for steers fed C vs HO (P < 0.01) or C vs ISO (P < 0.01), but daily gain and feed efficiency were not affected (P > 0.05) by treatments. Digestibility of DM, OM, starch, and GE was greater (P < 0.05) for the HO diet than the C diet, but lipid digestibility did not differ among treatments (P > 0.05). The combined effect of greater GE content and digestibility resulted in greater (P < 0.01) DE content for the HO than for the C diet. Calculated DE of the corn was 8.3% greater (3.74 Mcal/kg; P < 0.01) for the HO diet and 6.5% greater (3.67 Mcal/kg; P < 0.01) for the ISO diet than the corn in the C diet (3.25 Mcal/kg). Dry matter and GE digestibility did not differ (P > 0.05) between the C and ISO diets. Steers consuming ISO had greater (P < 0.05) starch digestibility than steers fed the C diet. Although HO had higher DE, DE intake was similar (P > 0.05) for HO and C due to lower DMI for HO. These results indicate that available energy is greater from high-oil corn than from typical corn, but depressed voluntary feed intake prevented performance improvements and resulted in equal energy intakes between high-oil corn and typical corn diets.     

Intake,digestibility, rumen protein synthesis,and growth performance of Malawi Zebu steers fed diets containing rangeland-based protein sources

Tropical Animal Health and Production - The study evaluated effects of feeding Malawi Zebu steers with diets containing baobab (Adansonia digitata) seed meal and white thorn tree (Vachellia...     

Effect of protease derived from Pseudoalteromonas arctica supplementation on growth performance,nutrient digestibility,meat quality,noxious gas emission and blood profiles in finishing pigs

This study was conducted to evaluate the effects of dietary supplementation of protease derived from Pseudoalteromonas arctica (PPA) in finishing pigs. A total of 160 pigs were used in this 10‐week trial. Dietary treatment groups were as follows: CON (basal diet); TRT1 (basal diet + 0.1% PPA); TRT2 (basal diet + 0.2% PPA); and TRT3 (basal diet + 0.3% PPA). During weeks 1–5, pigs fed with different levels of PPA‐supplemented diet showed linear increase (p < .05) in the apparent total tract digestibility (ATTD) of nitrogen (N) and linear decrease (p < .05) in the concentrations of serum total protein. During weeks 6–10, pigs fed with different levels of PPA‐supplemented diet showed a linear decrease in feed conversion ratio (p < .05). During the overall period, there was a linear decrease in feed conversion ratio (p < .05) associated with the inclusion of PPA. Pigs fed diets with 0.2% PPA supplementation had lower (p < .05) feed conversion ratio than those fed CON diet during weeks 6–10 and the overall period, and had higher (p < .05) ATTD of N than those fed CON diet during weeks 1–5. Pigs fed diets with PPA supplementation had lower (p < .05) concentrations of serum total protein than those fed CON diet on week 5. In conclusion, dietary supplementation with PPA diet has beneficial effects on growth performance, nutrient digestibility, backfat thickness and the concentrations of serum total protein.