乙酸钠对西门塔尔牛日粮能量平衡和氮平衡的影响

选用4头装有永久性瘤胃瘘管,年龄3.5岁,体重约500kg,体况良好的西门塔尔阉牛。采用4×4拉丁方设计,以混合精料和玉米秸秆为基础日粮,研究乙酸钠(0、200、400和600g/d)对西门塔尔牛日粮能量平衡和氮平衡的影响。结果表明:400g/d组和600g/d组消化能、代谢能、沉积能显著高于对照组和200g/d组(P<0.05),其中200g/d组沉积能显著高于对照组(P<0.05);400g/d组和600g/d尿能、消化能/总能、代谢能/总能、沉积能/消化能显著高于对照组(P<0.05);各处理组总能、气体能、产热量差异不显著(P>0.05);400g/d组和600g/d组粪氮含量显著降低(P<0.05);尿氮含量差异不显著(P>0.05);400g/d组和600g/d组可消化氮和沉积氮含量、氮利用率显著高于对照组和200g/d组(P<0.05),400g/d组显著高于600g/d组(P<0.05)。由此推断日粮中乙酸钠的适宜添加量为400g/d。     

Isoleucine and valine supplementation of a low-protein corn-wheat-soybean meal-based diet for piglets: growth performance and nitrogen balance

The effects of Ile and Val supplementation of a low-CP, corn-wheat-soybean meal-based piglet diet on growth performance, incidence of diarrhea, and N balance were studied using 60 Landrace x Duroc male piglets in a 4-wk experiment. The 60 individually caged piglets were divided into 5 dietary treatments, each consisting of 12 piglets. Diet 1 was a positive control diet (20% CP); diet 2 was a low-CP negative control diet (17% CP); diets 3, 4, and 5 were low-CP diets to which Ile, Val, or the combination of Ile and Val were added, respectively. All diets were supplemented with Lys, Met, Thr, and Trp to provide the required concentrations of these AA according to the 1998 NRC. Average daily gain and ADFI were similar among pigs fed the positive control, Val-added, and the Val plus Ile-added diets. On wk-2 and wk-4, fecal score was greater (softer feces) in piglets fed the 20% CP level compared with the remaining treatments (P < 0.01). Nitrogen intake was decreased (P < 0.0001) in pigs fed diets containing low levels of CP compared with pigs fed the 20% CP diet. Fecal N excretion (g/d) was decreased (P < 0.05) in piglets fed low-CP diets at wk 1 and wk 4 of feeding, and in urine at wk 4 of feeding. Crude protein levels or AA supplementation had no effect on N retention efficiencies. These results indicate that the supplementation of Val alone, or in combination with Ile, to a low-CP piglet diet with adequate levels of Lys, Met, Thr, and Trp is necessary to achieve maximum performance in pigs consuming corn-wheat-soybean meal-based diets.     

Effect of different dietary protein levels and amino acids supplementation patterns on growth performance,carcass characteristics and nitrogen excretion in growing-finishing pigs

Background: This study was conducted to determine the effects of different dietary protein levels and amino acids supplementation patterns in low protein diets on the growth performance, carcass characteristics and nitrogen excretion in growing-finishing pigs.Forty-two barrows(25.00 ± 0.39 kg) were randomly assigned to 7 diets. Diet 1: the high crude protein diet with balanced for 10 essential amino acids(EAAs). Diet 2: the medium crude protein diet with 2%(approx) decreased protein level of Diet 1 and balanced 10 EAAs. Diet 3: the low crude protein diet with 4% decreased protein level of Diet 1 and balanced 10 EAAs. The protein levels of Diet 4, 5, 6 and 7 were the same as that of Diet 3. Diet 4 was only balanced for lysine(Lys), methionine(Met), threonine(Thr) and tryptophan(Trp); Diet 5 and 6 were further supplemented with extra isoleucine(Ile) or valine(Val), respectively; Diet 7 was further supplemented with extra Ile + Val.Results: Over the 112 days trial, the reduction of dietary protein by 2% or 4% with balanced10 EAAs significantly decreased nitrogen excretion(P 0.05), but had no effects on growth performance and carcass characteristics(P 0.05). In low protein diet, Val supplementation significantly increased body weight gain at 25–50 kg phase(P 0.05), while Ile supplementation at 75–100 kg phase and 100–125 kg phase significantly reduced the ratio of feed to gain(P 0.05). No effect of different dietary protein levels and amino acids supplementation patterns in low protein diets on carcass characteristics was observed(P 0.05). The total N excretion of pigs supplemented with only Lys, Met, Thr and Trp was numerically higher than that of pigs fed with extra Ile, or Val, or Ile + Val diets.Conclusion: In low protein diet, Val is more required than Ile in the early growing phage(25–50 kg), while Ile becomes more required in the late growing and finishing phage(75–125 kg).     

日粮不同能量水平对中卫山羊育成母羊增重与屠宰性能的影响

选11月龄、健康、体重相近的中卫山羊育成母羊24只,随机分为3组,分别饲喂不同能量水平和精粗比的日粮,通过梯度饲养试验与屠宰试验结合的方法,研究日粮能量水平与精粗比对其增重与产肉性能的影响。结果表明:试验羊增重、日增重、屠宰率、净肉率、眼肌面积等产肉性能指标随日粮能量水平的增加而提高。     

低蛋白饲粮添加植酸酶和非淀粉多糖酶对生长猪生长性能和养分排泄量的影响

试验旨在研究低蛋白质饲粮添加植酸酶和非淀粉多糖(NSP)酶对生长猪生长性能、养分排泄量的影响。54头平均初始体重为(41.92±2.6)kg的杜长大三元杂交猪分为3组,每组3个重复,每个重复6头猪。1组为对照组(饲粮粗蛋白质水平为17.4%),2、3组为试验组,2组在1组基础上,饲粮粗蛋白质水平降至14.3%、总磷水平降低0.1个百分点,添加植酸酶;3组在2组基础上添加NSP酶,试验期38 d。试验结果表明,2组的平均日增重、料重比比1组分别提高7.64%和1.94%(P0.05),其余各组间差异不显著(P0.05);粪N浓度2、3组比1组分别降低18.58%、23.01%(P0.05);粪P浓度2、3组比1组分别降低40.23%、39.08%(P0.01)。由此可见,将常规饲粮粗蛋白质水平降低3个百分点、总磷水平降低0.1个百分点,并添加植酸酶,能显著提高生长猪平均日增重,显著减少粪氮含量,极显著减少粪磷含量;在此基础上,继续添加NSP酶不影响生长猪生长性能和粪中养分含量。     

Net energy,energy utilization,and nitrogen and energy balance affected by dietary pea supplementation in broilers

Pea starch consists predominantly of C-type of amylopectin chain which is more resistant to digestive enzymes than A-type of starch thus slowly digested in poultry. It was hypothesized that the presence of slowly digested pea starch in broiler diets will increase net energy and the efficiency of energy utilization in broilers. Two experiments were performed to investigate starch digestibility of pea at different incubation times (in vitro study) and the effect of dietary pea on heat increment and net energy in broilers using an open-circuit respiratory calorimetry system (in vivo study). One-day-old Ross 308 male broilers were fed a common starter crumble from d 1 to 10 and standard grower diets thereafter. At d 21, birds were transferred to the chambers each housing 2 birds. Each treatment was replicated 6 times with 2 identical runs of 3 replicates per treatment. A wheat-soybean meal-based diet was used as a control and the treatment diet contained 500 g of pea/kg pea. In vitro study showed that pellet processing increased (P < 0.001) starch digestibility, particularly at shorter times for wheat and a much larger response for pea. Birds offered the pea-based diet had lower (P = 0.002) feed intake, lower (P = 0.020) body weight gain, but a similar (P > 0.05) FCR compared to those offered the wheat-based diet. Net energy (NE) and apparent metabolizable energy (AME) values were higher in the pea-based diet than in the wheat-based diet (P = 0.037 for NE and P = 0.018 for AME). Heat production, respiratory quotient, heat increment of feed, efficiency of utilization of gross energy for AME, and efficiency of utilization of AME for NE did not differ (P > 0.05) between the 2 treatments. There was no effect (P > 0.05) of pea on the total tract digestibilities of dry matter, crude protein and ash, but the total tract digestibility of starch was higher (P = 0.022) in the pea-based diet compared to the wheat-based diet. This study provides insight into the energy metabolism of broilers offered a pea-based diet and indicates that dietary pea supplementation increases dietary AME and NE but has no effect on heat increment of feed and the efficiency of energy utilization in broilers.     

柠檬酸对西门塔尔牛日粮能量平衡和氮平衡的影响

选用4头年龄4岁、体况良好、平均体重500kg,装有永久性瘤胃瘘管的中国西门塔尔牛阉牛,采用4×4拉丁方设计．以混合精料和玉米秸秆为基础日粮,研究柠檬酸（0、100、200和300g／d）对日粮养分表观消化率的影响。结果表明：日粮添加柠檬酸200州组代谢能、沉积能、代谢能／总能、沉积能／消化能和沉积氮较对照组显著提高（P〈0．05）,沉积氮／消化氮较对照组极显著提高（P〈0．01）。根据试验结果推断日粮中柠檬酸的适宜添加水平为200g/d。     

Growth performance, energy, and nitrogen balance of weanling pigs fed a cereal-based diet supplemented with Chinese rhubarb

Forty Swiss Large White piglets of 4 weeks of age were used to determine the effect of dietary Chinese rhubarb on growth performance, as well as on energy and nitrogen metabolism by means of indirect respiration calorimetry studies. A cereal-based diet, supplemented with four different dosages of Chinese rhubarb (0.0%, 0.25%, 0.5%, 1%), was offered ad libitum to the piglets. Gaseous exchange was measured, and urine, faeces, and blood samples were taken. The addition of 0.25% dietary rhubarb increased feed intake (+32%) and daily weight gain (+67%) compared to the diet containing the greatest amount of rhubarb (1%). The piglets fed diet supplemented with 0.25% rhubarb digested and metabolised more energy and nitrogen relative to the animals of treatment 1%. As a consequence, the same group (0.25%) converted more energy and nitrogen into body protein than piglets receiving diet supplemented with 1% rhubarb. However, compared to the control group, the addition of 0.25% rhubarb to the diet resulted in not significantly alter growth performance, energy, and nitrogen metabolism of the animals.Blood parameters were not affected by the rhubarb supplementation. The dose-responding effect of Chinese rhubarb was reflected by the dry matter content of faecal samples. According to the laxative effect of higher doses of rhubarb, the addition of 1% rhubarb to the diet reduced dry matter content of faeces. This effect was well visible in practice, although not relevant in statistical terms. The addition of 0.5% dietary rhubarb had no relevant effect on growth performance or on energy and nitrogen metabolism of treated animals.     

生长獭兔日粮中添加菊花对其生长性能、肉质性状和经济效益的影响

为了研究中草药菊花在生长獭兔上的应用效果,选取体重相似、身体健康的40日龄獭兔56只,随机分为4组,分别饲喂基础日粮、基础日粮+1%菊花、基础日粮+2%菊花和基础日粮+3%菊花。试验结束时分别对其生长性能、肉质性状和经济效益进行了分析。结果表明:生长獭兔中添加菊花各试验组平均日增重,分别比对照组提高15.8%、31.8%、24.4%,差异显著(P<0.05);平均采食量分别比对照组提高16.62%、20.3%、16.21%,差异显著(P<0.05)菊花有改善肉质颜色的作用,对肌肉pH值、嫩度亦有改善的趋势,但差异不显著(P>0.05);饲料中添加菊花能够显著提高经济效益。结论:菊花营养价值丰富兼有药物功效,可作为生长獭兔的良好添加物,结合生长性能、肉质性状和经济效益多方面因素,本研究认为2%添加水平最为适宜。     

抗生素对生长肥育猪生产性能和血液指标的影响

抗生素作为饲料添加剂广泛地应用 ,促进了畜牧业和饲料工业的发展 ,提高了经济效益。根据我国的国情和畜牧业的发展状况 ,抗生素将在一定的时间内在畜牧业和饲料工业中大量应用。在养猪生产中 ,猪的年龄越小 ,使用抗生素的效果越显著。抗生素对畜禽免疫机能具有一定的抑制作用 ,但抗生素对血液指标的影响报道很少。本试验的目的旨在探索抗生素对生长肥育猪生产性能和部分血液指标的影响。1　材料与方法1 1　试验动物选择平均体重为 2 0ｋｇ的三元杂 (杜大长 )商品猪 5 0头母猪和阉公猪各半。分 2 0～5 0ｋｇ和 5 0～ 90ｋｇ两段饲养。于每…     

高精料舍饲条件下不同能量水平对生长期牦牛生长及血液生化指标的影响

试验旨在探究高精料舍饲下不同能量水平日粮对生长期牦牛生产性能及血液生化指标的影响.选取生长期健康阉牦牛18头,随机分为3个处理组,每组6个重复,进行全舍饲试验,预试期40d,正式试验期210 d.结果表明:中能量组和高能量组牦牛的平均日增重均显著高于低能量组(P＜0.05),高能量组牦牛平均日增重与饲喂时间呈显著的线性...     

Effect of phytase supplementation to a low- and a high-phytate diet for growing pigs on the digestibilities of crude protein, amino acids, and energy

Supplementation of microbial phytase usually improves the digestibility and utilization of phosphorus in feedstuffs of plant origin. The effect of phytase supplementation on the digestibilities of AA also has been examined, but the results have been inconsistent. This study was carried out to determine the effect of phytase (Natuphos) supplementation, at a rate of 2,000 phytase units/kg, to two basal diets on the apparent ileal digestibilities (AID) of GE, CP, and AA, and on the apparent total-tract digestibilities (ATTD) of CP and GE. The basal diets contained 18% CP and were formulated (as-fed basis) to contain either a low (0.22%) or high content (0.48%) of phytate P. The high-phytate diet contained 20% rice bran, which is a rich source of phytate and has low intrinsic phytase activity. Eight barrows (average initial BW = 40.6 kg), fitted with a simple T-cannula at the distal ileum, were fed the four diets according to a replicated 4 x 4 Latin square design. The pigs were fed twice daily at 0800 and 2000, equal amounts each meal, at a rate of 2.4 times the daily maintenance requirement for ME. Each experimental period comprised 14 d. Ileal digesta were collected from 0800 to 2000 on d 12, 13, and 14. Feces were collected from 0800 on d 8 until 0800 on d 12. Chromic oxide was used as the digestibility marker. The AID of GE, CP, and AA and the ATTD of CP and GE were less in the high- than in the low-phytate diet (P < 0.01). With the exception of glutamic acid, phytase supplementation did not affect (P > 0.10) the AID of CP and AA. There was no effect (P > 0.05) of phytase on the ATTD of CP and GE. These results show that if a response occurs to phytase supplementation, it is independent of the dietary phytate content.     

精准营养下低排饲粮对生长猪生长性能、骨骼特性及氮平衡的影响

试验旨在研究基于理想氨基酸模型,精准营养下低排饲粮对生长猪生长性能、骨骼特性及氮平衡的影响,为指导低排饲粮的推广应用提供依据。试验选取体重相近、健康的约20 kg杜×长×大三元杂交生长猪72头,随机分为2组,即对照组和试验组,每组6个重复,每个重复6头,分别饲喂基础饲粮和低排饲粮,试验期36 d。结果表明:相比对照组,低排饲粮对生长猪的生长性能无显著影响(P>0.05);低排饲粮对生长猪的骨骼发育无显著影响(P>0.05);低排饲料显著降低总氮摄入量、粪氮、尿氮和总氮排放量(P<0.05),显著提高氮沉积率和氮消化率(P<0.05)。在氨基酸平衡条件下,低排饲料对生长猪的生长性能和骨骼发育无显著影响,但能够降低氮排放,提高蛋白质的利用率。     

Effect of dietary energy concentration and apparent ileal digestible lysine:metabolizable energy ratio on nitrogen balance and growth performance of young pigs

Two experiments were conducted to determine the optimal apparent ileal digestible lysine:ME (Lys:ME) ratio and the effects of lysine and ME levels on N balance (Exp. 1) and growth performance (Exp. 2) in growing pigs. Diets were designed to contain Lys:ME ratios of 0.6, 0.7, 0.8, and 0.9 g/MJ at 13.5 and 14.5 MJ of ME/kg of diet in a 4 x 2 factorial arrangement. In Exp. 1, conventional N balances were determined on 48 crossbred barrows (synthetic line 990, initial BW = 13.1 +/- 0.7 kg) at approximately 15, 20, and 25 kg of BW with six pigs per diet. At 15 kg of BW, an energy density x Lys:ME ratio interaction on daily N retention was observed (P < 0.05). At each BW, N retention improved with an increase in N intake associated with increasing ME concentration. In 15-kg BW pigs, increasing the Lys:ME ratio increased daily N retention at the 13.5 (linear, P < 0.001) and 14.5 MJ of ME level (linear, P < 0.01; quadratic, P < 0.05). In 20-kg BW pigs, N retention (g/d) increased (linear, P < 0.001; quadratic, P < 0.01) and N retention (percentage) increased (linear, P < 0.001) as the Lys:ME ratio increased. At 25 kg of BW, N retention (g/d) increased quadratically (P < 0.05) with an increase in Lys:ME ratio. The Lys:ME ratios that maximized daily N retention at 15 kg of BW were 0.88 and 0.85 g/MJ at the 13.5 and 14.5 MJ of ME levels, respectively and 0.81 and 0.77 g/MJ (for both ME levels) at 20 and 25 kg of BW, respectively. Over the 28-d trial, an energy density x Lys:ME ratio interaction on ADG was observed (P < 0.05). Increasing energy density increased growth performance, whereas increasing the Lys:ME ratio in high-energy diets increased ADG (linear, P < 0.05; quadratic, P < 0.01) and gain:feed ratio (G/F) quadratically (P < 0.01). Average daily gain and G/F ratio were greatest in pigs fed the 14.5 MJ of ME diet and the Lys:ME ratio of 0.82 g/MJ. In Exp. 2, 128 individually housed crossbred barrows and gilts (initial BW = 12.8 +/- 1.6 kg) were used to determine the effect of diets used in Exp. 1 on growth performance in a 4 x 2 x 2 factorial arrangement. The ME level increased ADG and G/F from d 0 to 14 and from d 0 to 28. Increasing the Lys:ME ratio increased ADG from d 0 to 14, whereas growth performance was maximized in pigs fed Lys:ME ratio of 0.82 g/MJ. These results suggest that pigs from 13 to 20 and from 20 to 30 kg of BW fed diets containing 14.5 MJ of ME/kg had maximum N retention and ADG at 0.85 and 0.77 g of apparent ileal digestible lysine/MJ of ME, respectively.     

日粮中添加酵母核酸对断奶仔猪生长性能的影响

为探讨日粮中添加酵母核酸对断奶仔猪生长性能的影响,试验选取体重相近,公母各半,23日龄杜×长×大健康断奶仔猪120头,按照体重和公母比例随机分为三个处理组,每个处理组4个重复,每个重复10头仔猪,进行为期23 d的饲养试验。对照组使用正常营养标准的断奶仔猪料,试验组Ⅰ在仔猪料中添加0.3%的酵母核酸提取物(雅康宝450),试验组Ⅱ在仔猪料中添加0.5%的酵母核酸提取物。试验结果表明:在断奶仔猪料中添加酵母核酸提取物可显著地提高断奶仔猪的日均采食量(P<0.05)和平均日增重(P<0.05),显著降低断奶仔猪的腹泻率(P<0.05)。     

可消化纤维替代蛋白质对肉兔生长性能、能量和氮平衡及盲肠内容物组分的影响

文章旨在研究日粮不同可消化纤维与蛋白质比例对肉兔生长性能、能量和氮平衡及盲肠内容物组分的影响。试验选择32 d断奶的肉兔120只,随机分为4组,每组6个重复,每个重复5只。试验日粮分为4种,日粮可消化纤维与蛋白质比例分别为1.0(处理1组)、1.15(处理2组)、1.35(处理3组)和1.55(处理4组),试验共进行6周。结果 :处理3、4组较处理1、2组显著提高中性洗涤的表观消化系数(P <0.05),较处理1组显著提高了酸性洗涤纤维和粗纤维表观消化系数(P <0.05)。处理1组半纤维素表观消化系数最低(P <0.05),但可消化蛋白质和蛋能比最高(P <0.05)。处理1组较其他三组显著提高了氮的摄入量(P <0.05),处理3、4组较处理1组显著提高了能量沉积系数(P <0.05),日龄和日粮对尿氮排泄量和氮沉积量的影响具有显著交互效应(P <0.05)。处理1组较处理4组显著提高了盲肠内容物干物质含量(P <0.05)。结论 :日粮采用高比例可消化纤维替代蛋白质可以降低肉兔生长后期粪氨气和尿氮排泄量,提高氮沉积量。     

饲粮能量水平对渝荣Ⅰ号猪肥育后期生产性能和胴体肉质的影响

试验选用体重80 kg左右的渝荣Ⅰ号肥育猪60头,随机分为5个处理组,分别饲喂消化能浓度为12.99、13.49、14.09、14.57和15.07 MJ/kg的饲粮,每组3个重复,每个重复4头猪(公母各半),研究不同能量水平对猪肥育后期生产性能和胴体肉质的影响.结果表明:渝荣Ⅰ号猪肥育后期(80～120 kg)消化能浓度为14.09 MJ/kg时生产性能最佳.随着饲粮消化能浓度的提高采食量下降、料肉比降低,日增重各组间差异不显著(P>0.05).平均背膘厚和屠宰率随着饲粮中消化能水平的提高有上升趋势,但在最高能量组(15.07 MJ/kg)出现了下降,瘦肉率的变化与背膘厚和屠宰率相反;饲粮消化能浓度对各肉质性状均无显著影响(P>0.05).     

Effect of diet form and enzyme supplementation on growth, efficiency and energy utilisation of wheat-based diets for broilers

1. The effect of diet form (mash, cold-pelleted, steam-conditioned/pelleted, wet mash, whole wheat with balancer pellet, restricted pellet) and enzyme inclusion (Avizyme 1300, absent, present) was studied in 2 trials using individually caged, male broilers from 14 to 42 d. Bird performance, viscosity of ileal contents and diet metabolisability (AME) were measured. 2. The performance of mash-fed birds was significantly poorer than for the other treatments in relation to dry matter intake, liveweight gain and gain:food. This was not due to reduced diet AME content. 3. There was no significant effect of heat treatment on any of the variables measured, although viscosity of ileal contents was increased by 30% as compared to the cold-pelleted diet. 4. Gain:food was improved with wet-mash feeding in comparison to the dry mash treatment but it was concluded that this was not due to any intrinsic improvement in diet quality, but rather to voluntary food restriction on introduction of the wet food. 5. Whole wheat feeding improved gain:food and diet AME content by 3% as compared to the complete diets and caused approximately a 50% increase in gizzard weight as compared with the pelleted diets. 6. Food enzyme inclusion did not improve performance although a significant improvement in diet AME content was observed with enzyme inclusion in trial 1.