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1.
25~35kg生长猪可消化氨基酸的需要量   总被引:9,自引:2,他引:7  
本试验采用单因子试验设计法研究饲粮蛋白质 (CP)和可消化氨基酸水平对生长猪生产性能的影响。试验共设 5个处理 ,饲粮可消化赖氨酸 (Dlys)水平分别为 0 .4 0 %、0 .55%、0 .70 %、0 .85%和 1 .0 % ,Dlys/CP之比为 5%。饲粮等能 ( 1 3.72MJDE/kg) ,等氨基酸模式。其中 ,赖氨酸与可消化含硫氨基酸 (D-SAA)、可消化苏氨酸 (DThr)、可消化色氨酸 (DTrp)之比为 1 0 0 59 6 2 1 9。试猪为大白×长白杂交猪 ,平均起始重 2 5.1 8kg ,结束重 36 .86kg。结果表明 ,生长猪的平均日增重 (Y1)和饲料转化率 (Y2 )均随饲粮赖氨酸水平 (x)的增加呈显著的二次曲线变化。Y1(g) =-4 90 .4 2 7+ 2 6 91 .0 31X -1 50 1 .84 1X2   R2 =0 .996 2Y2 =9.891 -1 6 .784X + 9.36 5X2 R2 =0 .990 9当赖氨酸水平分别为 0 .8959%、0 .896 1 %时 ,平均日增重和饲料转化率分别达 71 5g和 2 .37。由此推算 ,2 5~ 35kg生长猪达到最大生产性能的Dlys、D -SAA、DThr、DTrp及CP的需要量分别为 0 .896 %、0 .52 9%、0 .556 %、0 .1 70 %、1 7.92 0 % ,饲粮CP/DE为 1 3.0 6g/MJ,Dlys/CP为 5.0 0 % ,Dlys/DE为 0 .6 5g/MJ。  相似文献   

2.
60—100kg肥育猪可消化氨基酸需要量研究   总被引:4,自引:0,他引:4  
选用大白×长白杂交猪60头,试验采用单因子试验设计,随机分为5个处理,每个处理4个重复(圈),每个重复3头猪.5个处理饲粮DLys水平分别为0.30、0.41、0.53、0.64和0.75%,相应的CP分别为7.69、10.24、12.62、15.19、17.57%.饲粮等能(13.68MJ DE/kg),等氨基酸模式,其氨基酸模式DLysD-SAADThDTrp为100636720.试猪始重61.18±5.20kg,末重100.04±6.04kg.试验除考察生产性能外,试验还同时测定了氨基酸的回肠表观消化率.结果表明,肥育猪的ADG(Y1)、F/G(Y2)均随饲粮DLys水平(X)的增加呈显著的二次曲线变化.当DLys水平分别为0.56%和0.55%时,ADG和F/G分别达到极大值(910.97g)和极小值(3.20).由此可推算,60~100kg肥育猪达最佳生产性能的DLys、D-SAA、DTh、DTrp和CP需要量分别为0.55、0.35、0.37、0.11、13.20%.  相似文献   

3.
应用部分扣除饲粮氨基酸(AA)的氮平衡试验法研究了大白×长白猪生长阶段(35~60kg)和育肥阶段(60~90kg)的可消化赖(DLys)、蛋 +胱(D -SAA)、苏(DThr)、色氨酸(DTrp)平衡模式。每个阶段各用18头猪进行N平衡试验。每个N平衡试验均设6个处理组 ,即高蛋白基础日粮组(BD)、低蛋白加合成AA对照组(PC)、在PC基础上分别将研究的扣除25 %4种氨基酸的其它4个试验组。每个处理设3个重复 ,每重复1头猪。饲粮为玉米—豆粕—玉米蛋白粉型。所有饲粮等能(3.40McalDE/kg) ,基础饲粮CP与DLys水平相应为161g/kg、5.28g/kg。试验结果表明 ,按单位代谢体重的N沉积与可消化氨基酸摄入量计算 ,大长猪生长阶段DLys、D -SAA、DThr、DTrp的平衡比例为100 :49 :72 :19 ;育肥阶段为100 :34 :64 :23。表明氨基酸平衡模式因猪的体重阶段不同而异  相似文献   

4.
不同理想蛋白质水平对生长猪氮代谢的影响   总被引:4,自引:0,他引:4  
本试验采用单因子试验设计 ,选择体重 54.0 4± 3.0 7kg的健康大白×长白杂交猪 2 0头 ,随机分为 5组 ,每组 4个重复 ,进行氮平衡试验。在等能等氨基酸 (AA)模式 (DLys∶D -SAA∶DThr∶DTrp为 1 0 0∶6 0∶6 1∶1 8)的基础上 ,研究了 5种不同理想蛋白质 (IP)水平的饲粮对生长猪氮代谢的影响。 5种饲粮的CP和DLys分别为 8.6 1、1 1 .33、1 4 .0 6、1 6 .6 7、1 9.2 9%和 0 .33、0 .4 6、0 .58、0 .71、0 .83%。试验结果表明 ,氮沉积 (NR)随IP水平的提高而增加 ,当CP为 1 6 .6 7%和DLys为 0 .71 %时 ,NR最大 ,之后再增加IP水平 ,NR又明显下降。氮排泄率随IP水平的提高而减少 ,当CP为 1 6 .6 7%和DLys为0 .71 %时 ,氮排泄率最少 ( 4 7.4 2 % ) ,之后再增加IP水平 ,氮排泄率又增多。血清尿素氮 (PUR)随IP水平的提高而增加。用回归分析发现。当DLys为 0 .77%时 ,CP为 1 8.1 % ,日粮具有最高消化率和最大NR及最低氮排泄  相似文献   

5.
35~60kg生长猪可消化氨基酸需要量研究   总被引:6,自引:0,他引:6  
本试验是按照理想蛋白质(IPP)的原理 ,研究35~60kg 生长猪DAA需要量 ,为我国猪饲养标准的修订积累资料。选用大白×长白杂交猪60头 ,试验采用单因子试验设计 ,随机分为5个处理 ,每个处理4个重复 ,每个重复3头猪(饲养于一圈)。5个处理饲粮可消化赖氨酸(DLys)水平( %)分别为0.33、0.46、0.58、0.71和0.83 ,相应的CP( %)分别为8.61、11.33、14.06、16.67、19.29。饲粮等能(13.64MJDE/kg) ,等氨基酸模式 ,其可消化氨基酸模式Lys:SAA:Thr:Trp 为100 :60 :61 :18。试猪始重35.2±3.58kg,末重59.57±6.37kg。试验除考察生产性能外 ,在试验…  相似文献   

6.
试验选用初始体重为 12 .9kg± 2 .6kg杜×长仔猪 72头 ,随机分配到 18个圈栏 ,每栏 2头母猪和 2头去势公猪。试验饲粮针对不同蛋白饲料原料设计为 3个处理 ,每个处理设 6个重复。 3个处理饲粮的蛋白饲料类型分别为 10 0 %豆粕、2 5 %豌豆和 75 %豆粕、5 0 %豌豆和 5 0 %豆粕。试验依猪体重分 2 0~ 35kg、35~ 6 0kg和 6 0~ 90kg 3个饲养阶段 ,分别检测试验猪各阶段的平均日增重 (ADG)、平均日采食量 (ADFI)和饲料转化率。试验结果表明 ,试验猪在体重 2 0~ 90kg的全程生长肥育期 ,饲料转化率 (P >0 .0 5 )处理之间无显著差异 ,但ADG (P <0 .0 5 )和ADFI (P <0 .0 5 )差异显著。 10 0 %豆粕、2 5 %豌豆和 5 0 %豌豆等各处理的ADG和ADFI分别为 90 7g和 2 .6 5kg、85 8g和 2 .4 5kg ,以及 84 9g和 2 .4 5kg。  相似文献   

7.
3.4~9.5kg超早期断奶仔猪粗蛋白质需求参数研究   总被引:3,自引:0,他引:3  
试验研究饲粮不同粗蛋白质 (CP)水平 ( 1 6% ,1 8% ,1 9% ,2 0 % ,2 1 % ,2 2 % ,和 2 4 % )对 3.4~ 9.5kg超早期断奶仔猪生产性能和血清尿素氮 (SUN)浓度的影响。结果表明 :当饲粮CP水平从 1 6%升高到2 0 % ,仔猪平均日增重趋于增加 (P >0 .0 5) ,饲料转化率极显著提高 (P <0 .0 1 ) ,采食单位粗蛋白质所获得的体增重和SUN浓度无显著变化 (P >0 .0 5) ;当饲粮CP水平从 2 0 %升高到 2 4 % ,仔猪平均日增重趋于下降 (P >0 .0 5) ,饲料转化率趋于降低 (P >0 .0 5) ,采食单位粗蛋白质所获得的体增重显著降低(P <0 .0 5) ,SUN浓度极显著升高 (P <0 .0 1 )。以上结果表明 ,在满足氨基酸需要的条件下 ,3.4~ 9.5kg超早期断奶仔猪生长所需的饲粮CP水平为 2 0 %。  相似文献   

8.
肥育猪可消化赖氨酸需要量研究   总被引:1,自引:0,他引:1  
本试验旨在确定70~100 kg猪可消化赖氨酸(DLys)的最佳需要量。选用60头平均体重约70 kg的三元杂交杜长大猪,随机分为5组,每组3个重复。以酶解酪蛋白法(EHC)测定的饲料原料DLys含量为基础按理想蛋白质氨基酸模式(IAAP)配制日粮(等能、等氨基酸模式),通过测定不同剂量DLys处理组猪生长性能、血液指标及胴体品质,确定70~100 kg猪可消化赖氨酸(DLys)的最佳需要量。结果表明:(1)DLys水平为0.47%~0.59%时,平均日增重(ADG)、无脂瘦肉生长指数(FFLI)随DLys水平的提高而增加,0.59%DLys组达到最大,分别为782 g/d和313.8 g/d(P<0.05),之后随DLys水平的提高而下降;(2)料肉比(F/G)随DLys的提高先下降后上升,0.5 9%DLys组最低为3.2 0(P<0.0 1);(3)血浆尿素氮(SUN)浓度随DLys水平的升高而显著上升(P<0.0 5),眼肌面积也随之显著增大(P<0.05),背膘厚则变薄;(4)0.59%DLys组生长激素(GH)水平显著高于其他各组(P<0.05)。另外,血清总蛋白(TP)、游离甲状腺素T3(FT3)水平各组间无显著差异。综合试验结果表明,70~100 kg猪DLys最佳需要量为0.59%(15.9 g/d),相应的粗蛋白质为12.96%,以消化能浓度表示则为0.43 g/MJ。  相似文献   

9.
试验比较研究了平均体重(33.64±1.2)kg 的大白×长白生长猪与平均体重(32.5±0.8)kg 的雅南猪可消化赖、蛋 +胱、苏、色氨酸平衡模式。按照氨基酸(AA)部分扣除氮沉积比较法 ,分别用18头大长猪和18头雅南猪进行N平衡试验。每个N平衡试验均设6个处理组 ,即高蛋白基础饲粮组(BD)、低蛋白加合成氨基酸对照组(PC)、在PC基础上轮流将所研究的4种AA扣除25 %的其它4个试验组。每个处理设3个重复 ,每个重复1头猪。饲粮为玉米—豆粕—玉米蛋白粉型。所有饲粮等能(3.40McalDE/kg) ,基础饲粮CP与可消化Lys水平相应为161g/kg、5.28g/kg。试验期大长猪日喂料120g/kgW 0.75,雅南猪日喂料100g/kgW 0.75。试验结果表明 ,按单位代谢体重的N沉积与可消化AA摄入量计算 ,大长猪AA平衡比例为 :Lys100、Met +Cys49、Thr72、Trp19 ;雅南猪为 :Lys100、Met+Cys78、Thr76、Trp21。结果显示 ,饲粮可消化氨基酸平衡模式因猪的基因型不同而异。与外种猪比较 ,雅南猪需要比较高比例的蛋 +胱、苏氨酸和色氨酸。  相似文献   

10.
本研究旨在理想氨基酸模式下,探讨不同氨基酸水平的低蛋白质饲粮对后备母猪初情日龄、血清代谢产物和激素浓度的影响。选用96头体貌相近、平均体重为(69.01±3.43)kg的长白×大白杂交后备母猪,随机分成4个组,每个组4个重复,分别饲喂4种不同可消化赖氨酸(DLys)水平的低蛋白质饲粮,并通过添加合成氨基酸保证4组饲粮中可消化赖氨酸、可消化含硫氨基酸、可消化苏氨酸和可消化色氨酸的值一致。70~100kg阶段,饲粮DLys水平为0.61%(组1)、0.66%(组2)、0.71%(组3)、0.76%(组4);100~125kg阶段,饲粮DLys水平为0.55%(组1)、0.60%(组2)、0.65%(组3)、0.70%(组4)。结果表明,增加饲粮DLys水平显著提高血清中赖氨酸(Lys)浓度,对血清甘油三酯(TG)和葡萄糖(GLU)浓度的影响不显著(P0.05);血清胰岛素(INS)、胰岛素样生长因子-I(IGF-I)、促黄体素(LH)和雌二醇(E2)浓度随饲粮DLys水平的增加而提高,试验组3达到最高值(P0.05),之后随DLys水平的增加而降低,试验组3血清INS浓度显著高于试验组1(P0.05);后备母猪背膘厚和发情率随着饲粮DLys水平的增加呈现先升高后降低的趋势(P0.05),初情日龄试验组3比试验组4显著提前(P0.05)。综上表明,在理想氨基酸模式下,长大后备母猪70~100kg阶段和100~125kg阶段饲粮DLys适宜日摄入量分别为17.82和17.29g·d~(-1),即饲粮DLys水平分别为0.71%和0.65%时,有利于提高后备母猪血清代谢激素INS、IGF-I和生殖激素LH、E_2的浓度,缩短初情期日龄,提高发情率。  相似文献   

11.
后备荣昌母猪适宜消化能和赖氨酸需要量研究   总被引:2,自引:0,他引:2  
旨在探讨研究35~55 kg后备荣昌母猪适宜日粮消化能(DE)与表观可消化赖氨酸(ADLys)水平。选用(34.45±4.53)kg后备荣昌母猪216头,随机分为12个处理,每个处理6个重复,每个重复3头。采用3×4因子设计,日粮DE分别为11.72、12.34和12.97 MJ/kg,ADLys分别为0.43%、0.53%、0.63%和0.73%。结果表明:随着日粮DE水平的提高,试验猪日增重显著提高(P0.05),饲料增重比显著降低(P0.05),P2背膘厚显著增加(P0.01),母猪发情率呈现上升趋势(P0.1)。日粮Lys水平提高使血清尿素氮含量呈现上升趋势(P0.1)。在本试验条件下,35~55 kg后备荣昌母猪适宜日粮DE和ADLys水平分别为12.97MJ/kg和0.43%。  相似文献   

12.
Sixty male and 60 female crossbred pigs were allocated to an experiment to investigate the effects of porcine somatotropin (pST) administration (0 or 6 mg/d) and dietary lysine content on growth performance, tissue deposition, and carcass characteristics over the live weight range of 80 to 120 kg. Pigs receiving pST were given diets containing 6.9, 7.8, 8.8, 9.7, 10.6, or 11.5 g lysine/kg, whereas control pigs received diets containing 4.8, 5.8, 6.9, 7.8, 8.8 or 9.7 g lysine/kg. These dietary levels ranged from 0.40 to 0.70 g available lysine/MJ of DE for pST-treated pigs and from 0.28 to 0.58 g available lysine/MJ of DE for control pigs. Pigs were individually housed in pens, and there were five replicates of each treatment. All diets contained 14.5 MJ of DE/kg and were offered for ad libitum consumption to pigs between 80 and 120 kg live weight. Growth rate increased exponentially and food conversion ratio (FCR) decreased exponentially with increasing levels of lysine. In addition, there was a significant sex x pST interaction such that pST reduced the sex difference in FCR. Growth rate was faster in boars than in gilts and was increased by pST at the higher levels of dietary lysine. Similarly, FCR was lower for boars than for gilts and was decreased by pST at the higher dietary lysine levels. The optimum growth rate and FCR were defined as the lysine level at which growth rate and FCR were 95% and 105%, respectively, of the lysine plateau. The optimum growth rate and FCR were achieved at similar dietary lysine contents and were approximately 0.35 and 0.52 g available lysine/MJ of DE for control and pST-treated pigs, respectively. Protein deposition in the carcass increased exponentially with increasing dietary lysine level, was higher in boars than in gilts, and was increased by pST at the higher dietary lysine contents. Sex had no effect on dietary lysine required to maximize protein deposition. The dietary lysine contents required to ensure 95% of plateau protein deposition of 104 and 153 g/d were 0.39 and 0.55 g available lysine/MJ of DE for control and pST-treated pigs, respectively. The increase in lysine requirement with pST seems to be commensurate with the increase in protein deposition.  相似文献   

13.
Two experiments were conducted to compare the nutritional adequacy of a genetically improved high-lysine, high-oil corn (HLHOC; .408% lysine, 6.21% fat, as-fed basis) and a high-oil corn (HOC; .289% lysine, 5.97% fat, as-fed basis) for young growing pigs. Experiment 1 used four non-littermate barrows (initially 20.0 kg BW) fitted with ileal T-cannulas in a crossover-designed digestion study. The .75% total lysine diets contained 8.5% casein and an equal amount of lysine (.25%) from the test corn. Apparent ileal digestibilities of amino acids, GE, DM, and CP were similar (P > .10) between diets. Apparent ileal lysine digestibilities were 65 and 71% for the HOC and HLHOC, respectively, assuming the lysine in casein to be 100% digestible. Experiment 2 used 100 barrows reared in a segregated early-weaning environment (initially 8.3 kg BW and 27 d of age) to evaluate five corn-soybean meal-based diets in a 2 x 2 factorial arrangement with main effects being corn type and dietary lysine (.80 or 1.15% digestible lysine). The fifth diet consisted of the .80% digestible lysine HOC diet supplemented with .23% additional L-lysine x HCl (.975% digestible lysine) to verify that lysine was the limiting amino acid in the low-lysine diets. Increasing digestible lysine from .80 to 1.15% increased (P < .001) ADG and gain/feed (G/F) regardless of corn variety. Combined ADG and G/F were .347 kg and .641 and .443 kg and .790 for the .80 and 1.15% digestible lysine diets, respectively. Within lysine level, corn type did not affect ADG, ADFI, or G/F (P > .10). The results of these studies indicate that the lysine in HLHOC is as available as the lysine in HOC and that HLHOC can be used successfully in swine diets.  相似文献   

14.
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)=  相似文献   

15.
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.  相似文献   

16.
We conducted two experiments to evaluate the effects of dietary energy density and lysine:calorie ratio on the growth performance and carcass characteristics of growing and finishing pigs. In Exp. 1, 80 crossbred barrows (initially 44.5 kg) were fed a control diet or diets containing 1.5, 3.0, 4.5, or 6.0% choice white grease (CWG). All diets contained 3.2 and 2.47 g of lysine/Mcal ME during growing (44.5 to 73 kg) and finishing (73 to 104 kg), respectively. Increasing energy density did not affect overall ADG; however, ADFI decreased and feed efficiency (Gain:feed ratio; G:F) increased (linear, P < .01). Increasing energy density decreased and then increased (quadratic, P < .06) skinned fat depth and lean percentage. In Exp. 2, 120 crossbred gilts (initially 29.2 kg) were used to determine the effects of increasing levels of CWG and lysine:calorie ratio fed during the growing phase on growth performance and subsequent finishing growth. Pigs were fed increasing energy density (3.31, 3.44, or 3.57 Mcal ME/kg) and lysine:calorie ratio (2.75, 3.10, 3.45, or 3.80 g lysine/Mcal ME). No energy density x lysine:calorie ratio interactions were observed (P > .10). Increasing energy density increased ADG and G:F and decreased ADFI of pigs from 29.5 to 72.6 kg (linear, P < .05). Increasing lysine:calorie ratio increased ADG and ADFI (linear, P < .01 and .07, respectively) but had no effect on G:F. From 72.6 to 90.7 kg, all pigs were fed the same diet containing .90% lysine and 2.72 g lysine/Mcal ME. Pigs previously fed with increasing lysine:calorie ratio had decreased (linear, P < .02) ADG and G:F. Also, pigs previously fed increasing CWG had decreased (linear, P < .03) ADG and ADFI. From 90.7 to 107 kg when all pigs were fed a diet containing .70% lysine and 2.1 g lysine/Mcal ME, growth performance was not affected by previous dietary treatment. Carcass characteristics were not affected by CWG or lysine:calorie ratio fed from 29.5 to 72.6 kg. Increasing the dietary energy density and lysine:calorie ratio improved ADG and G:F of growing pigs; however, pigs fed a low-energy diet or a low lysine:calorie ratio from 29 to 72 kg had compensatory growth from 72 to 90 kg.  相似文献   

17.
Three experiments were conducted with broiler chickens to evaluate the effects of digestible threonine (DThr) and crude protein (CP) on their performance at three different phases of age: 1–14, 15–28 and 29–42 days. The measured traits included the following: average daily gain (ADG), feed intake (FI), feed conversion ratio (FCR), carcass crude protein (CCP), body lipid (BL), feather weight gain (FWG), protein deposited in feather (FCP), carcass plus feather protein (CFCP), carcass Thr deposition (CDThr) and nitrogen excretion (NE). A dilution technique was used to create seven diets (with eight replicates) increasing the DThr content from 1.5 to 10 g/kg of diet for phase 1, 1.3–8.9 g/kg of diet for phase 2, and 1.2–8.2 g/kg of diet for phase 3. Data measured were imported into neural networks (NNs) to: (i) predict the measured traits in response to DThr and CP, (ii) rank the importance of DThr and CP on these traits through sensitivity analysis and (iii) find the optimal levels of DThr and CP that lead to the desired (maximum or minimum) responses. For each trait investigated, 50 different random groups of data were generated using a bootstrapping method. These 50 data groups were then used to develop 50 separate NNs which were subsequently combined to construct the final ensemble NN model. In general, accuracy of the models constructed was acceptable, although models of high (ADG, FCR, CFCP, BL, DThr and NE; 0.64 ≤ R2 ≤ 0.99) and low (CCP, FWG and FCP; 0.26 ≤ R2 ≤ 0.79) accuracy were obtained. All models developed showed the greatest sensitivity to DThr. This may be explained by the dilution technique diet preparation used in these experiments. Optimization results showed decreases in optimal values of DThr and CP with increasing age for all traits. The highest level of DThr was suggested for minimum BL, followed by minimum FCR, maximum ADG, maximum CFCP, minimum NE and maximum CCP respectively. Results showed that the optimal values of DThr for minimum FCR in phases 1–3 were 8.5, 7.4 and 6.4 g/kg of diet, while these values for maximum ADG were 8.2, 7.2 and 6.4 g/kg of diet respectively.  相似文献   

18.
本试验旨在研究饲粮能量水平对育成期崂山奶山羊能量利用率的影响。选择体重为(18.43±0.76)kg的崂山奶山羊育成母羊30只,采用单因素随机分组设计分成3组,每组10个重复,每重复1只羊。分别饲喂粗蛋白质、钙及磷水平基本一致,消化能水平分别为10.40、11.47及12.51 MJ/kg的3种全混合日粮。预试期10 d,正试期90 d。结果表明:1)试验后期3组试羊随着饲粮能量水平的提高,总能消化率依次提高,12.51 MJ/kg组试羊的总能消化率、总能代谢率及消化能代谢率显著高于10.40 MJ/kg组(P0.05);3组试羊的总能、粪能及尿能间呈显著差异(P0.05),10.40 MJ/kg组11.47 MJ/kg组12.51 MJ/kg组;10.40 MJ/kg组试羊的甲烷能显著低于11.47及12.51 MJ/kg组(P0.05)。2)10.40 MJ/kg组试羊末重及平均日增重显著低于11.47及12.51 MJ/kg组(P0.05),但11.47 MJ/kg组与12.51 MJ/kg组间无显著差异(P0.05)。3)育成期崂山奶山羊消化能和代谢能需要量与代谢体重和平均日增重关系的回归公式:DE=0.675W~(0.75)+0.110ADG(P=0.006,R~2=0.982);ME=0.526W~(0.75)+0.076ADG(P=0.027,R~2=0.873)[式中DE为消化能(M J/d),ME为代谢能(M J/d),W~(0.75)为代谢体重(kg),ADG为平均日增重(g)]。综合得出,育成期崂山奶山羊母羊饲粮中消化能以11.47~12.51 MJ/kg(干物质基础)较为适宜。  相似文献   

19.
试验旨在研究不同营养水平日粮对海南黑山羊肥育羔羊生长性能和器官指数的影响。采用2×3析因设计,将24只3月龄、体重为(10.56±1.28)kg海南黑山羊随机分成6个处理组,每个处理组4只羊(公、母各半),每只羊为1个重复。6个不同营养水平精饲料处理组分别为:试验1组粗蛋白质(CP)水平为15%、消化能(DE)水平为11.72 MJ/kg,试验2组CP 15%、DE 12.55 MJ/kg,试验3组CP 15%、DE 13.39 MJ/kg,试验4组CP 17%、DE 11.72 MJ/kg,试验5组CP 17%、DE 12.55 MJ/kg,试验6组CP 17%、DE 13.39 MJ/kg,试验期90 d。结果表明,精饲料粗蛋白质水平对试验羊平均日增重影响显著(P<0.05),17% CP日粮组试验羊有较高的平均日增重(P<0.05)和较低的料重比(P<0.05);日粮精饲料蛋白质和能量水平对心脏、肝脏、脾脏、肺脏、肾脏、胃的脏器指数影响均不显著(P>0.05),随着精饲料消化能水平的增加,肠道的脏器指数逐渐减小(P<0.05)。结果提示,补饲不同营养水平精饲料对3月龄海南黑山羊育肥期羔羊平均日增重和料重比均有显著影响(P<0.05),对黑山羊肠道重量及肠道器官指数影响显著(P<0.05),而对其他内脏器官指数无显著影响(P>0.05)。  相似文献   

20.
试验选取健康、体重一致、12周龄的红腹锦鸡15只,随机分为5个处理,每个处理设3个重复,每个重复1只,试验期为12周,分别饲喂蛋白质水平不周的5种试验日粮(A组16.78%,B组17.76%,C组18.75%,D组19.75%,E组20.67%)。在试验期间,采用全收粪法收集所有样品,并测定样品。研究日粮蛋白质水平对育成期红腹锦鸡生长性能、营养物质消化率的影响。结果表明:日粮代谢能在同一水平上(12.14MJ/kg),蛋白质水平为18.75%时,平均日增重为3.13g,平均日采食量为21.51g,料重比为6.87。日增重和料重比均与其他各组差异显著(P〈0.05)。平均目采食量在各组之间差异不显著(P〉0.05)。蛋白质水平为18.75%时的蛋白质消化率明显高于其他各组(P〈0.05)。目粮代谢能为12.14MJ/kg,蛋白质水平为18.75%时,为红腹锦鸡育成期适宜粗蛋白质需要量。  相似文献   

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