不同蛋白水平大麦日粮对生长育肥猪生产性能和粪尿氮排放的影响

本文通过两个试验研究不同蛋白水平大麦日粮对生长育肥猪生产性能和粪尿氮排放的影响。试验一:将108头33.6±2.23kg杜长大杂交生长育肥猪随机分成3组,分别饲喂粗蛋白水平为17.45%、16.21%和15.15%的3种大麦日粮,结果表明:各试验组育肥猪日增重、日采食量和饲料转化率间无显著差异(P>0.05)。试验二:将9头体重约20kg的健康杜长大杂交生长育肥猪,随机分成3组,分别饲喂粗蛋白水平为17.45%、16.21%和15.15%的3种大麦日粮,于消化代谢室进行消化代谢试验。结果表明,采食每千克日粮粪尿氮排放量减少8.12%～15.2%。总之,以大麦为主要能量饲料配制的生长育肥猪日粮,粗蛋白降低1.24%～2.3%,生长育肥猪生产性能无影响,但能减少粪尿氮排放。     

粗纤维和赖氨酸水平对生长期豫南黑猪的影响

本试验旨在探讨饲粮中不同粗纤维和赖氨酸水平对生长期豫南黑猪生长性能、血清生化指标及营养物质表观消化率的影响.试验选取162头体重为30 kg左右的豫南黑猪,采用3（CF：4％、5.5％、7％）×3（lys：0.75％、0.85％、0.95％）两因子交叉完全随机设计,共设9个处理,每个处理3个重复,每重复6头猪.通过测定其生长性能、血清生化指标及营养物质表观消化率,确定生长期豫南黑猪的最佳粗纤维和赖氨酸水平.结果表明：不同粗纤维和赖氨酸水平对生长期豫南黑猪平均日采食量（ADFI）、平均日增重（ADG）和料重比（F/G）均无显著影响（P＞0.05）;粗纤维和赖氨酸水平分别为7％、0.75％时,料重比最低（P＜0.05）;粗纤维和赖氨酸水平分别为5.5％、0.85％时血清中游离三碘甲状腺原氨酸（FREET3）水平最高（P＜0.05）.饲粮中添加粗纤维使营养物质表观消化率下降,但通过适量比例的粗纤维和赖氨酸的合理添加,对饲粮中能量、粗蛋白、粗脂肪、粗纤维、Ca和P的表观消化率无显著影响（P＞0.05）.上述结果提示,30～60 kg生长期豫南黑猪的饲粮适宜粗纤维水平和赖氨酸水平分别为7％和0.75％.     

日粮不同消化能水平对育肥猪生长性能的影响

为确定最适宜的加×(长×大)三元杂交育肥猪日粮消化能(DE)水平,根据育肥猪不同生长阶段的能量需求差异,试验分20～60 kg和60～100 kg两个阶段,测定日增重和料重比。试验结果表明,20～60 kg阶段,对照组育肥猪的个体重、平均日增重和料重比都相对高于其他2组,但差异不显著。60～100 kg阶段,试验2组育肥猪的个体重、平均日增重和料重比相对高于其他3组,但差异不显著。综合分析,20～60 kg生长阶段,加×(长×大)三元杂交育肥猪的最适日粮消化能水平为13.4 MJ/kg;60～100 kg育肥阶段,最适日粮消化能水平为13.2 MJ/kg。     

不同营养水平日粮补充复合植物提取物对育肥猪生长性能、养分消化及血液指标的影响

文章旨在评估不同蛋白质水平日粮补充复合植物提取物对育肥猪生长性能、养分表观消化及血液生化指标的影响。试验选择512头18周龄平均体重为（76.10±0.21）kg的商品猪随机分为4组,每组8个重复,每个重复16头。试验日粮采用2×2因子设计,T1组为低蛋白质日粮+0 mg/kg植物提取物,T2组为低蛋白质日粮+80 mg/kg植物提取物,T3组为高蛋白质日粮+0 mg/kg植物提取物,T4组为高蛋白质日粮+80 mg/kg植物提取物。结果：15.5%蛋白质水平组育肥猪末重、平均日增重及饲料效率较13.5%蛋白质水平组分别显著提高3.00%、8.55%和7.94%（P＜0.05）。与13.5%蛋白质水平组相比,15.5%蛋白质水平组育肥猪干物质和氮表观消化率分别显著提高2.79%和4.27%（P＜0.05）。日粮蛋白质和复合植物提取物添加水平以及其交互作用对育肥猪血清IGF-1、葡萄糖、甘油三酯、尿素氮及肌酸酐浓度的影响均无显著差异（P＞0.05）。结论：低蛋白质日粮（13.5%）降低育肥猪的日增重、饲料效率及干物质和氮表观消化率,但补充80 mg/kg复合植物提取物可以在一定程度改善上述负面影响。 [关键词]营养水平|植物提取物|育肥猪|生长性能|养分消化     

15～30 kg陆川猪能量和粗蛋白质水平的研究

选择80头健康、胎次相近,体重接近15 kg的陆川猪阉公猪。随机分为4组,每组设2个重复,每个重复10头。研究日粮中不同营养水平对生长期陆川猪生产性能、屠宰性能和肉质性状的影响,以确定陆川猪在生长阶段所需能量、粗蛋白的最佳水平。结果表明：1）不同营养水平对平均日采食量、平均日增重和料重比均无显著影响。2）随着营养水平的提高,可使眼肌面积增大、瘦肉率提高。3）随着营养水平的降低,降低肉色评分、增加大理石纹评分和提高肌内脂肪含量。在生长期,陆川猪适宜的消化能为12.55 MJ/kg,粗蛋白水平为15.50%。     

可溶性干酒糟（DDS）在育肥猪日粮中的应用研究

研究了可溶性干酒糟（DDS）作为饲料原料对生长育肥猪生长性能的影响。选用72头健康体重约70 kg的三元育肥猪,随机分成2个处理组,每个处理组2个重复,每个重复18头猪,对照组饲喂基础日粮,试验组饲喂含40%DDS的试验日粮,试验正式期20 d。结果显示,与对照组相比,试验组育肥猪的平均日增重、平均采食量和料肉比方面无明显差异（P>0.05）,从经济效益分析来看,与对照组相比,试验组猪在日采食成本和日增重成本方面分别下降了1.41元/kg和1.50元/kg,整个育肥周期每头猪可多获利约75元。试验证实在生长育肥猪的日粮中添加DDS能够完全满足育肥猪的生长需要,并可降低养殖成本,进一步提高经济效益。     

15～30kg陆川猪能量和粗蛋白质水平的研究

选择80头健康、胎次相近，体重接近15kg的陆川猪阉公猪。随机分为4组。每组设2个重复，每个重复10头。研究日粮中不同营养水平对生长期陆川猪生产性能、屠宰性能和肉质性状的影响，以确定陆川猪在生长阶段所需能量，粗蛋白的最佳水平。结果表明：1）不同营养水平对平均日采食量、平均日增重和料重比均无显著影响。2）随着营养水平的提高，可使眼肌面积增大、瘦肉率提高。3）随着营养水平的降低，降低肉色评分、增加大理石纹评分和提高肌内脂肪含量。在生长期，陆川猪适宜的消化能为12．55MJ／kg，粗蛋白水平为15．50％。     

蜂胶在仔猪饲养中应用效果的研究

72头初重（18±kg）健康状况良好三元杂交仔猪（公母各半）采用随机分组法处理,每个处理3个重复,每个重复8头猪。对照组日粮为基础日粮中添加金霉素等抗生素,试验组基础日粮中添加850mg/kg蜂胶。试验为期28天。在试验结束时,以酸不溶灰分（4N HCL）为内源指示剂,测定各处理仔猪对饲料干物质、能量、粗蛋白的消化率。结果表明,与对照组相比,试验组仔猪的日增重和饲料转化率均有改善（P〉0．05）。以蜂胶为主要成分的添加剂对预防仔猪腹泻有显著效果,试验仔猪腹泻率较对照组明显降低。试验组仔猪对于物质、能量、粗蛋白的消化率显著高于对照组（P〈0．05）。蜂胶可以作为新型添加剂在仔猪生产中使用。     

不同净能水平日粮对不同体重阶段猪生长性能和能量摄入量的影响

试验旨在研究不同净能水平的日粮对不同体重阶段猪的生长性能和能量摄入量的影响。试验1选择12头初始体重（24.50±0.96）kg的杜×长×大三元杂交健康去势公猪，随机分为3组，每组4个重复，每个重复1头猪。3个日粮处理分别为低净能水平日粮（9.63 MJ/kg）、中净能水平即对照组日粮（10.26 MJ/kg）和高净能水平日粮（10.89 MJ/kg）。试验采用拉丁方设计连续进行7期，每6天为1期。试验2选择180头体重（75.4±1.4）kg的三元杂交健康猪，按体重和性别将猪随机分为5个组，每组5个重复，每个重复6头猪（3公3母），日粮净能水平分别为8.87、9.14、9.41、9.69、9.96 MJ/kg。试验1结果表明：相较于对照组，高净能组与低净能组猪的日采食量下降（P<0.05）；高净能组的饲料转化率和日增重均高于低净能组（P<0.05）。试验2结果表明：猪日粮净能值为9.69、9.96 MJ/kg时，猪的耗料增重比最低（P=0.09）。由此可见，日粮净能水平的增加会降低猪的采食量，改善饲料转化率；猪体重阶段在75～100 kg时，适宜的日粮净能水平为9.69 ...     

不同蛋白质水平日粮添加山苋菜提取物对育肥猪生长性能、养分消化及血清指标的影响

文章旨在评估不同蛋白质水平日粮补充山苋菜提取物对育肥猪生长性能、养分消化及血清生化指标的影响。试验将576头体重接近的15周龄育肥猪随机分为4组，每组6个重复，每个重复24头。试验日粮采用2×2因子设计，即粗蛋白质水平（12.5%和14.0%）及山苋菜提取物添加水平（0和150 mg/kg），试验持续7周。结果：高蛋白质日粮组肥猪末重、平均日增重和饲料效率均显著高于低蛋白质日粮组（P＜0.05），而150 mg/kg山苋菜提取物组育肥猪的料重比显著降低（P＜0.05）。高蛋白质水平日粮或补充150 mg/kg山苋菜提取物均显著提高了干物质和粗蛋白质表观消化率（P＜0.05）。高蛋白质日粮组血清总蛋白、尿素氮、肌酸酐、IGF-1和生长激素浓度均显著高于低蛋白质日粮组（P＜0.05），同时日粮补充150 mg/kg山苋菜提取物也显著提高了血清总蛋白、IGF-1和生长激素浓度（P＜0.05）。结论：在本试验条件下，降低育肥猪日粮蛋白质水平可降低干物质、粗蛋白质表观消化率，进而对日增重和饲料效率造成负面影响，补充150 mg/kg山苋菜提取物可缓解低蛋白对育肥猪造成的负面影响。 [关键词]山苋菜提取物|育肥猪|生长性能|养分消化|血清指标     

营养水平对鲁农2号生长猪屠宰性能和肉品质的影响

试验选用108头鲁农2号生长猪(49.58±1.49)kg,随机区组,分为3个处理组,每处理4个重复,每重复(圈)9头猪,在保持日粮消化能/粗蛋白质比例不变的情况下,分为高、中、低3个营养水平组,研究日粮不同消化能和粗蛋白质水平对鲁农2号生长猪屠宰性能和肉品质的影响。试验分50～80 kg和80～100 kg两个体重阶段饲养,当试验猪平均体重达到100 kg时进行屠宰,测定屠宰性能和肉品质。结果表明:3个处理组的背膘厚、眼肌面积、后腿重、后腿比例、脂肪率、屠宰率和瘦肉率均差异不显著(P>0.05);除大理石纹外,3个处理组的肉品质差异也不显著(P>0.05)。这预示着低能量和粗蛋白质日粮饲喂鲁农2号生长猪可以获得与高能量粗蛋白质日粮相近的屠宰性能和肉品质。     

Effects of protein deprivation on subsequent growth performance,gain of body components,and protein requirements in growing pigs

Forty-eight barrows were used in a 2 x 6 factorial arrangement to test a hypothesis that feeding a protein-deficient diet affects subsequent growth response by altering the efficiency of protein utilization. Barrows were individually fed either a 9% crude protein (CP) diet or an 18% CP diet from 20 to 30 kg of body weight (BW) (depletion phase). From 30 to 45 kg BW (realimentation phase), pigs were fed one of six experimental diets with CP levels of 11.8, 13.1, 14.3, 15.6, 18.8, and 21.8%. Four pigs were slaughtered at 20 kg BW to determine initial body composition. Four pigs from each treatment in depletion phase (a total of eight) were slaughtered at 30 kg BW, and all pigs from each treatment in realimentation phase (a total of 36) were slaughtered at 45 kg BW for subsequent compositional analysis. Pigs were bled at 20, 30, and 40 kg BW for blood urea nitrogen (BUN), insulin-like growth factor (IGF)-I, and IGF-binding protein (IGFBP) assays. Pigs were given three times the maintenance digestible energy requirement (3 x 120 kcal BW(-0.75) x d(-1)) in three equal meals daily. The feed allowance was adjusted every 3 d. During the depletion phase, pigs fed the 18% CP diet grew faster and more efficiently (P < 0.01) and gained more (P < 0.01) water and protein than did pigs fed the 9% CP diet. Pigs fed the 18% CP diet showed higher (P < 0.01) BUN values, IGF-I concentrations, and IGFBP ratios than pigs fed the 9% CP diet. During the realimentation phase, pigs fed the 9% CP diet during the depletion phase grew faster (P < 0.05), tended to grow more efficiently (P = 0.066), gained more water (P < 0.01), and tended to gain more protein (P = 0.068) than pigs fed the 18% CP diet during the depletion phase. Pigs fed the 9% CP diet during the depletion phase tended (P = 0.069) to have a higher protein requirement during the realimentation phase than pigs fed the 18% CP diet during the depletion phase. When measured at 40 kg BW, pigs fed the 9% CP diet had a lower (P < 0.05) BUN than pigs fed the 18% CP diet during the depletion phase. However, the plasma IGF-I concentration and IGFBP ratio at 40 kg BW were not affected by dietary CP level fed during the depletion phase. This study indicates that pigs fed a protein-deficient diet exhibit compensatory growth. During the period of compensatory growth, the requirement of CP for those pigs is higher than that of pigs previously fed an adequate diet. This study also suggests BUN can be used as an indicator of protein utilization efficiency and compensatory growth.     

半细毛羊5种玉米的可消化粗蛋白质和有效能的测定及其预测

本试验旨在采用概略养分分析法测定5种玉米的营养成分含量以及通过消化代谢试验实测玉米的可消化粗蛋白质含量和有效能值,并利用先采集的4种玉米(奥美特、杰尼336、巨丰66、京科665)数据拟合可消化粗蛋白质、消化能和代谢能分别与营养成分之间的回归方程,然后利用第5种玉米(禾育九)可消化粗蛋白质和有效能数据来对回归方程进行验证和修正。选取16只体重为(56.44±5.11)kg的云南半细毛羊,采用完全随机设计,平均分为4组,每组4只。试验共分2期进行,共6种日粮,分别是基础日粮和5种试验日粮,第1期饲喂4种日粮,第2期饲喂2种日粮。结果表明:京科665的可消化粗蛋白质(DCP)、消化能(DE)和代谢能(ME)含量最高,杰尼336的DCP、DE和ME含量最低;玉米的DE和ME分别与EE呈极显著负相关关系(P<0.01),相关系数分别为-0.985和-0.994;试验所得的预测方程为DCP(g/kg)=258.961-52.624EE(粗脂肪)、DE(MJ/kg)=40.506-6.876EE、DE(MJ/kg)=34.677-6.398EE+0.492CP(粗蛋白质)、DE(MJ/kg)=-115.182-6.572EE+0.473CP+1.525OM(有机物)、ME(MJ/kg)=-1.028+0.945DE、ME(MJ/kg)=2.950+0.916DE-1.060CF(粗纤维)和ME(MJ/kg)=37.586-6.586EE。综合DCP含量和有效能值,京科665的品质最佳,其次是巨丰66、奥美特和禾育九,杰尼336品质最差;以半细毛羊为试验对象得出,可以利用玉米的营养成分预测其DCP含量以及有效能值。     

不同日粮蛋白能量水平对伊犁马产奶性能和乳成分的影响

试验采用2因子4水平饱和D-最优回归设计以研究日粮粗蛋白和消化能对伊犁马泌乳后期产奶量、乳成分的影响,通过响应曲面回归分析获得伊犁马泌乳后期适宜粗蛋白和消化能的需要量.选取年龄11～12周岁、体重410 kg±30 kg、胎次4～5胎,处于第3泌乳月的伊犁马30匹,随机分为6个试验组,每组5个重复.单栏定量饲养,分别饲以6种不同DE和CP水平的日粮,试验期60 d.试验结果显示,随着粗蛋白和消化能摄入的增加,日估计产奶量逐渐增加,其中以日粮4组（CP 1 352 g/d,DE 25.5 Mcal/d）最大,为8 156 mL/d.日粮4组的乳脂率、乳蛋白率、锌、锰在各组中最高,分别为0.99％、1.77％、1.12 μg/mL和28.96 ng/mL,而体细胞数和磷最少,分别为10.60×10^3个/mL和0.32 mg/mL.乳糖、总固体物、钙和铜含量在各组间均无显著差异（P＞0.05）.日产奶量与粗蛋白和消化能的回归关系为：日产奶量（mL/d）=-1.052 1×10^5 ＋581.678 3×DE＋116.6012×CP-0.111 0×DE×CP-0.037 2×CP^2-1.958 5×DE^2 （P＜0.05）.研究结果提示：DE和CP日摄入量影响处于泌乳后期伊犁马的产奶量和乳成分,400 kg体重伊犁马泌乳后期DE和CP的适宜需要量分别为108.05MJl/d和1 419.32g/d.     

Comparative total tract digestibility of dietary energy and nutrients in growing pigs and adult sows

Seventy-seven diets were fed to 61-kg growing pigs at a feeding level close to their ad libitum intake and to nonlactating, nonpregnant sows slightly above their maintenance energy level (2.4 kg/d). The main objectives of this study were to compare the total tract digestibility of dietary energy or nutrients of the 77 diets in growing pigs and adult sows and to analyze the effect of diet chemical composition on total tract digestibility in both groups of pigs. Diets were formulated to represent a range of chemical compositions as large as those found in most practical situations. The DE and ME values and total tract digestible nutrient contents of diets were measured for each group of animals; each diet was measured in four to five animals per group, and collection of urine and feces lasted 10 d. The results were used to establish equations for predicting DE and ME values, total tract digestible nutrient contents, and total tract digestibility coefficients of energy from chemical characteristics for each group of animals. The results show that the total tract digestibility of energy or nutrients was higher (P < 0.01) in adult sows than in growing pigs; the total tract digestibility coefficients of energy, crude protein, ether extract, and NDF averaged 85.2, 85.1, 37.1, and 64.4%, respectively, for sows and 82.1, 80.3, 31.6, and 56.3%, respectively, for growing pigs. The ME/DE ratio was lower (P < 0.01) in sows (94.8%) than in growing pigs (96.5%), as a result of higher urinary energy losses in sows. The difference in DE values (on average, 0.6 MJ/kg of DM) between adult sows and growing pigs was not constant (P < 0.01) but increased with dietary fiber content (3.3, 8.6, and 10.1 kJ for each gram of NDF, ADF, and crude fiber increase in the diet, respectively), which suggests that the origin of the difference between the two physiological stages is mainly due to a higher rate of degradation of dietary fiber in the hindgut of sows. The DE and ME values could be accurately predicted from total tract digestible nutrients or from chemical characteristics for each physiological stage. Equations for predicting urinary energy loss from urinary N are also proposed. From a practical point of view, it is suggested to use two energy values for pig feeds: one applicable to growing-finishing pigs and one to adult sows. Equations for predicting DE in adult sows from energy values obtained in growing pigs are proposed.     

Influence of dietary protein level, amino acid supplementation, and dietary energy levels on growing-finishing pig performance and carcass composition

Two experiments were conducted to determine the effects of feeding reduced-CP, AA-supplemented diets at two ambient temperatures (Exp. 1) or three levels of dietary NE (Exp. 2) on pig performance and carcass composition. In Exp. 1, 240 mixed-sex pigs were used to test whether projected differences in heat increment associated with diet composition affect pig performance. There were 10 replications of each treatment with four pigs per pen. For the 28-d trial, average initial and final BW were 28.7 kg and 47.5 kg, respectively. Pigs were maintained in a thermoneutral (23 degrees C) or heat-stressed (33 degrees C) environment and fed a 16% CP diet, a 12% CP diet, or a 12% CP diet supplemented with crystalline Lys, Trp, and Thr (on an as-fed basis). Pigs gained at similar rates when fed the 16% CP diet or the 12% CP diet supplemented with Lys, Trp, and Thr (P > 0.10). Pigs fed the 12% CP, AA-supplemented diet had a gain:feed similar to pigs fed the 16% CP diet when housed in the 23 degrees C environment but had a lower gain:feed in the 33 degrees C environment (diet x temperature, P < 0.01). In Exp. 2, 702 gilts were allotted to six treatments with nine replicates per treatment. Average initial and final BW were 25.3 and 109.7 kg, respectively. Gilts were fed two levels of CP (high CP with minimal crystalline AA supplementation or low CP with supplementation of Lys, Trp, Thr, and Met) and three levels of NE (high, medium, or low) in a 2 x 3 factorial arrangement. A four-phase feeding program was used, with diets containing apparent digestible Lys levels of 0.96, 0.75, 0.60, and 0.48% switched at a pig BW of 41.0, 58.8, and 82.3 kg, respectively. Pigs fed the low-CP, AA-supplemented diets had rates of growth and feed intake similar to pigs fed the high-CP diets. Dietary NE interacted with CP level for gain:feed (P < 0.06). A decrease in dietary NE from the highest NE level decreased gain:feed in pigs fed the high-CP diet; however, gain:feed declined in pigs fed the low-CP, AA-supplemented diet only when dietary NE was decreased to the lowest level. There was a slight reduction in longissimus area in pigs fed the low-CP diets (P < 0.08), but other estimates of carcass muscle did not differ (P > 0.10). These data suggest that pigs fed low-CP, AA-supplemented diets have performance and carcass characteristics similar to pigs fed higher levels of CP and that alterations in dietary NE do not have a discernible effect on pig performance or carcass composition.     

棉籽浓缩蛋白营养价值评定及其对断奶仔猪生长性能的影响

本研究旨在评价棉籽浓缩蛋白的营养价值及其替代大豆浓缩蛋白对断奶仔猪生长性能、营养物质消化率和血清生化指标的影响。试验1：将12头生长猪随机分成2组（每组6个重复，每个重复1头猪），分别饲喂玉米基础饲粮和棉籽浓缩蛋白饲粮。采用全收粪尿法和套算法测定棉籽浓缩蛋白的消化能和代谢能。试验2：将12头生长猪随机分成2组（每组6个重复，每个重复1头猪），分别饲喂无氮饲粮和棉籽浓缩蛋白饲粮。采用指示剂法和直接法测定棉籽浓缩蛋白的粗蛋白质和氨基酸标准回肠消化率。试验3：将192头断奶仔猪随机分成4组（每组6个重复，每个重复8头猪），分别饲喂棉籽浓缩蛋白水平为0、2%、4%和6%（等量替代大豆浓缩蛋白）的试验饲粮，试验期28 d。结果表明：1）风干基础下棉籽浓缩蛋白消化能、代谢能和总能消化率分别为16.51 MJ/kg、15.38 MJ/kg和89.78%。2）棉籽浓缩蛋白的粗蛋白质和氨基酸标准回肠消化率89%和75%～94%。3）不同添加水平的棉籽浓缩蛋白替代大豆浓缩蛋白对断奶仔猪生长性能、营养物质消化率及血清生化指标均没有显著影响（P>0.05）。由此可见，棉籽浓缩蛋白在断奶仔猪饲粮中可以完全...     

20～50 kg川藏黑猪的能量代谢与沉积规律研究

本试验旨在研究20~50 kg川藏黑猪的能量代谢与沉积规律。试验一:选择体重接近[(20.17±3.46)kg]的川藏黑猪配套系商品猪64头,预试7 d后屠宰4头猪测定胴体成分;其余试验猪按公母随机分成5个组,每个组4个重复,每个重复3头,各重复单圈饲养,自由采食消化能(DE)水平分别为13.79、13.37、12.96、12.54和12.12 MJ/kg的饲粮。试验猪体重达50 kg时,结束试验一,测定平均日采食量、平均日增重和料重比,并在各组选择1头猪屠宰测定胴体成分。试验二:选择试验一中15头体重接近[(48.34±4.07)kg]的公猪,随机分成5个组,每个组3个重复,每个重复1头,单独饲养于代谢笼,分别采食上述5种DE水平的饲粮,进行消化代谢试验。预试期3 d,正试期4 d。采用析因法建立能量需要量预测模型。结果表明:饲粮DE水平影响了20~50 kg川藏黑猪的平均日采食量、平均日增重和料重比;饲粮DE转化为代谢能(ME)效率(ME/DE)为97.26%~98.10%,ME用于沉积产品能的效率(DED/ME)平均值为41.71%;此阶段川藏黑猪维持需要ME平均值为0.49 MJ/W~(0.75)或0.85 MJ/W~(0.60)(按DE计为0.50 MJ/W~(0.75)或0.87 MJ/W~(0.60)),增重需要DE和ME平均值分别为18.91和18.47 MJ/kg。由此得出,20~50 kg阶段川藏黑猪能量需要模型为:DE(MJ/d)=0.504 W~(0.75)+18.91ΔW或DE(MJ/d)=0.867 W~(0.60)+18.91ΔW;ME(MJ/d)=0.492 W~(0.75)+18.47ΔW或ME(MJ/d)=     

Effects of feeding diets containing low crude protein and coarse wheat bran as alternatives to zinc oxide in nursery pig diets

Two experiments were conducted to determine the effects of crude protein (CP) level in diets containing coarse wheat bran (CWB) with or without pharmacological levels of Zn (provided by zinc oxide: ZnO) on growth performance and fecal DM of nursery pigs. In experiment 1, 360 barrows (Line 200 × 400, DNA, Columbus, NE, initially 5.6 kg) were allotted to 1 of 6 dietary treatments from d 0 to 21 after weaning with 5 pigs per pen and 12 pens per treatment. Treatments included a positive control diet (21% CP) with 3,000 mg/kg Zn in phase 1 and 2,000 mg/kg in phase 2; negative control (21% CP) with 110 mg/kg added Zn, and 4 diets containing 4% CWB and 110 mg/kg added Zn formulated to contain 21%, 19.5%, 18%, or 16.5% CP. The 2 control diets and 21% CP CWB diet contained 1.40% standardized ileal digestible (SID) Lys in phase 1 and 1.35% SID Lys in phase 2, while the 19.5%, 18%, and 16.5% CP diets contained 1.33, 1.25 and 1.20% Lys, respectively, in both phases. Pigs fed the positive control diet containing pharmacological ZnO had increased (P < 0.05) ADG and G:F compared with the negative control and the 21% CP CWB diet. Reducing CP (concurrently with SID Lys) in diets containing CWB decreased ADG and G:F (linear, P = 0.002); however, fecal DM increased (linear, P = 0.005). In experiment 2, two groups of 300 and 350 pigs, initially 7.0 and 6.2 kg, respectively, were used with 5 pigs per pen and 26 pens per treatment. The objective was to determine if adding back essential AA would improve growth performance of pigs fed the low CP diets. All dietary treatments were fed for 13 days, contained 4% CWB, and consisted of: (1) positive control with 2,000 mg/kg of Zn and 21% CP (1.35% SID Lys); (2) no ZnO and 21% CP; and 3 diets with no ZnO formulated to 18% CP and (3) 1.2% SID Lys; (4) 1.35% SID Lys by the addition of feed grade amino acids (AA), and (5) diet 4 with non-essential amino acids (NEAA; Gly and Glu). Pigs fed 21% CP with ZnO had increased (P = 0.001) ADG compared to those fed 18% CP (1.35% SID Lys) with high levels of feed grade amino acids or those fed the reduced SID Lys (1.2%) diet. Overall, G:F was improved (P < 0.001) for pigs fed 21% CP diets and those fed the 18% CP diet with NEAA compared to pigs fed 1.2% SID Lys and pigs fed high levels of feed grade amino acids. Fecal DM was increased for pigs fed the reduced SID Lys diet. In summary, pharmacological levels of Zn improve pig growth performance, but reducing CP (and subsequently SID Lys) decreased nursery pig growth performance.     

猪脱酚棉籽蛋白能量及粗蛋白质消化率的比较评定

研究旨在评定猪对脱酚棉籽消化能和粗蛋白表观消化率,并比较脱酚棉籽蛋白(DCP)与豆粕(SBM)之间差异。选用体重(36.2±1.6)kg的杜×长×大三元杂交猪6头,采用套算法、双3×3拉丁方试验设计,试验日粮分别为脱酚棉籽蛋白日粮、豆粕日粮和基础日粮,每个拉丁方阶段包括5 d预饲期、5 d正式期,整个试验共30 d。结果表明,脱酚棉籽蛋白、豆粕消化能含量分别为12.41 MJ/kg、13.62 MJ/kg。脱酚棉籽蛋白、豆粕中粗蛋白表观消率化分别为73.35%、82.05%,表观可消化粗蛋白含量分别为37.92%、35.45%。脱酚棉籽蛋白是新型蛋白质原料,其消化能含量为豆粕的91.11%,粗蛋白表观消率化为豆粕的89.39%,可消化粗蛋白含量为豆粕的106.99%。脱酚棉籽蛋白在猪饲料中的应用具有广阔的前景。