不同蛋白水平日粮对不同形态含氮化合物在血液中~(15)N丰度及组织中净流量的影响

本试验旨在研究不同蛋白水平日粮对不同形态含氮化合物在血液中15N丰度及组织中净流量的影响。选择4头体况良好且装有颈动脉、颈静脉、门静脉和肠系膜静脉插管的徐淮白山羊,采用4×4拉丁方设计,配制蛋白水平分别为8.5%、11.0%、13.5%和16.0%的4种日粮。结果表明:血液中pH和蛋白态15N丰度不受蛋白水平影响(P>0.05),但显著影响(P<0.05)总15N、氨态15N、尿素态15N和游离氨基酸态15N丰度,且均在11%蛋白水平下达到峰值;从组织中净流量来看,除蛋白态15N净流量外,PDV和MDV组织中其他各形态含氮化合物15N净流量均随日粮中蛋白水平的提高出现先升高后降低的趋势,组间差异显著(P<0.05),且都在11%蛋白水平下达到峰值。综上可知,日粮蛋白水平为11%时对徐淮白山羊内源尿素氮代谢的周转效果最好。     

不同蛋白日粮对山羊瘤胃环境参数的影响

试验采用4×3拉丁方试验设计,研究豆粕、棉籽粕、菜籽粕、玉米酒糟4种不同蛋白质日粮对3只徐淮白山羊瘤胃发酵参数的影响。结果表明,4种不同蛋白源日粮对山羊瘤胃内环境有显著的影响,玉米酒糟组pH值最高;豆粕和棉籽粕组氨氮浓度与玉米酒糟组相比差异显著(P<0.05),与菜籽粕组相比差异极显著(P<0.01);4种蛋白源的瘤胃总VFA浓度分别为87.44、66.67、80.63、82.73mmol/l,其中以豆粕组最高,显著高于菜籽粕组(P<0.05),极显著高于棉籽粕组(P<0.01);以棉籽粕组最低,极显著低于其它3组。     

不同酪蛋白添加水平对湖羊肠系膜排流组织、门静脉排流组织中游离氨基酸和肽结合氨基酸净流量的影响

本试验旨在研究饲粮不同酪蛋白添加水平对湖羊血浆中游离氨基酸(FAA)和肽结合氨基酸(PAA)释放量及肠系膜排流组织(MDV)、门静脉排流组织(PDV)净流量的影响.选用3只体况良好的湖羊,安装肠系膜静脉、门静脉和颈动脉插管.采用4×3不完全拉丁方试验设计,试验羊分别饲喂4种不同酪蛋白添加水平(A:0、B:3.0%、C:6.0%、D:9.0%)的饲粮.结果显示,湖羊血浆氨基酸浓度随着饲粮酪蛋白添加水平的升高而升高.MDV的FAA净流量以D组最高,且显著高于A组(P<0.05);PAA净流量则是C组最高,且显著高于A、B组(P<0.05).PDV的FAA和PAA净流量都是C组最高,且显著或极显著高于A、B组(P<0.05或P<0.01).结果提示,在一定范围内,饲粮蛋白质水平影响湖羊MDV和PDV中FAA和PAA的净流量.     

十二指肠灌注大豆小肽和氨基酸对奶山羊小肠肽吸收的影响

本试验探讨了十二指肠灌注大豆小肽和氨基酸对奶山羊小肠肽结合氨基酸和游离氨基酸吸收的影响.选取4只体况良好,体重(38.38±3.09)kg的泌乳奶山羊,安装永久性十二指肠近端瘘管和门静脉、肠系膜静脉以及颈动脉慢性血管插管进行试验.采用交叉试验设计,分别向十二指肠灌注60 g/d大豆小肽以及与60g大豆小肽总氨基酸含量相同的氨基酸.结果表明,与灌注氨基酸相比,灌注大豆小肽显著增加肠系膜排流组织(MDV)总肽结合氨基酸净流量(P<0.05),门静脉排流组织(PDV)总肽结合氨基酸净流量高于灌注氨基酸组,但2组间差异不显著(P>0.05).而灌注氨基酸显著增加奶山羊MDV和PDV总游离氨基酸净流量(P<0.05).研究表明,小肠中肽含量的增加可以促使其在小肠的吸收.     

不同蛋白质日粮对山羊瘤胃左静脉和肠系膜静脉氨基酸浓度的影响

选取3只体重33 kg左右,安装瘤胃左静脉、肠系膜静脉插管的徐淮白山羊,研究不同植物源性蛋白质日粮对山羊瘤胃左静脉和肠系膜静脉氨基酸及小肽吸收的影响.试验采用4×3不完全拉丁方设计,选用豆粕、棉籽粕、菜籽粕、玉米酒糟四种不同植物源性蛋白质日粮,按13%粗蛋白质水平配制单一蛋白质源日粮(精粗比3:7).试验结果表明:瘤胃左静脉游离氨基酸(fluid amino acid,FAA)和肽氨基酸(pcptide amino acid,PAA)总浓度以豆粕组最高,吸收进入瘤胃左静脉FAA中含量较高的是谷氨酸和精氨酸,PAA中含量较高的是苯丙氨酸,肠系膜静脉FAA和PAA总浓度以玉米酒糟组最高,吸收进入肠系膜静脉FAA中含量较高的是丝氨酸和亮氨酸,PAA中含量较高的是丝氨酸、精氨酸、缬氨酸.     

不同蛋白日粮对山羊肠道内环境参数的影响

试验采用4×3拉丁方试验设计，研究了豆粕、棉籽粕、菜籽粕、玉米酒糟4种不同蛋白质日粮对3只徐淮白山羊瘤胃发酵参数的影响。结果表明：4种不同蛋白源日粮对山羊肠道内环境有显著影响，豆粕组pH值最高，氨氮浓度以棉籽粕组最高，豆粕和棉籽粕纽pH值、氨氮浓度与其他两组差异显著（P〈0．05）；十二指肠总VFA浓度分别为6．07、5．66、6．58和5.09mmol／L；其中菜籽粕与玉米酒糟组差异显著（P〈0.05）。     

十二指肠灌注不同水平大豆小肽对奶山羊小肠小肽吸收的影响

本试验旨在研究十二指肠灌注大豆小肽对奶山羊小肠小肽和游离氨基酸吸收的影响。选择7只体况良好、体质量相近的奶山羊((37.88±3.03)kg),安装永久性十二指肠近端瘘管和门静脉、肠系膜静脉近端和远端以及颈动脉慢性血插管进行4×4拉丁方试验,分别从十二指肠灌注生理盐水、60、120、180g.d-1大豆小肽。结果表明,随着十二指肠大豆小肽灌注水平的提高,奶山羊肠系膜排流组织(MDV)总肽结合氨基酸净流量显著增加(P0.05或P0.01);60、120、180g.d-1组门静脉排流组织(PDV)总肽结合氨基酸净流量均显著高于对照组(P0.05),但3个大豆小肽灌注组间无显著性差异(P0.05)。奶山羊小肠对小肽的吸收率随小肠中肽量的增加而下降。随着大豆小肽灌注水平的增加,奶山羊MDV和PDV组织游离氨基酸净流量显著增加(P0.05)。随十二指肠大豆小肽灌注水平的提高,试验羊颈静脉血浆尿素氮浓度显著增加(P0.05),对血浆葡萄糖、胰岛素、生长激素、胰高血糖素和IGF-1浓度没有显著影响(P0.05)。研究结果表明,大豆小肽灌注增加奶山羊小肠中肽结合氨基酸的流量,提高了MDV肽结合氨基酸的净流量,但因肽结合氨基酸吸收率降低或/和肽结合氨基酸吸收细胞降解率提高,降低了进入肠系膜静脉的肽结合氨基酸的比率。     

不同植物蛋白的日粮对山羊胃肠道食糜氨基酸和肽的影响

选择3只徐淮白山羊,采用4×3拉丁方设计研究不同植物性蛋白源日粮(A:豆粕、B:棉籽粕、C:菜籽粕、D:玉米酒糟)对瘤胃和十二指肠内氨基酸和肽的影响。结果表明:各处理组瘤胃内的游离氨基酸、肽氨基酸浓度分别为8.55、5.38、7.37和7.74mg/L和41.76、36.89、33.65、29.59mg/L;游离氨基酸组成以Glu、Pro所占比例相对较大,Gly、Thr、Leu和Phe所占比例相对较小。肽氨基酸组成以Asp、Glu、Ser、Pro、Val含量相对较高,而Arg、Phe含量相对较低。十二指肠食糜游离氨基酸、肽氨基酸浓度分别为48.71、32.26、35.72、51.23mg/L和11.28、8.54、9.95、12.54g、100gDM;其中游离氨基酸中以Tyr、Ala、Val、Leu、Phe含量相对较高,His、Cys含量相对较低。各组中总氨基酸含量以Ala、Val、Leu、Phe含量相对较高,His、Cys含量相对较低;进入十二指肠的菌体蛋白氨基酸含量,以豆粕组最高,进入十二指肠的饲料氨基酸含量,以玉米酒糟组最高。     

极低蛋白日粮不同蛋白源对仔猪生长性能和氮代谢的影响

本试验在补充9种晶体氨基酸的极低蛋白(14%)日粮的条件下,研究不同蛋白来源日粮对仔猪生长性能和氮代谢的影响。将36头体重相近(14.62±1.46 kg)的杜×长×大阉公仔猪随机分为4组,分别饲喂蛋白源由豆粕、棉籽粕、豆粕-棉籽粕和鱼粉组成的日粮。结果表明:与豆粕相比,棉籽粕和鱼粉显著降低了末重和平均日增重、增加了饲料增重比(P0.05),豆粕-棉籽粕组与豆粕组差异均不显著(P0.05);棉籽粕和鱼粉都显著降低了血清总蛋白含量(P0.05);棉籽粕和豆粕-棉籽粕显著降低了血清白蛋白的含量(P0.05);棉籽粕显著增加血清中尿素的含量(P0.05),而豆粕-棉籽粕显著降低其含量(P0.05);棉籽粕显著降低粪氮含量(P0.05);棉籽粕能够显著增加尿氮含量(P0.05),鱼粉则显著降低其含量(P0.05);棉籽粕显著降低了氮沉积率(P0.05),而豆粕-棉籽粕和鱼粉显著增加了氮沉积率(P0.05)。因此,补充晶体氨基酸后,以棉籽粕-豆粕为蛋白源的极低蛋白日粮能够获得与豆粕相近的生长性能,且氮排放比豆粕降低10.68%。     

不同蛋白原料对绵羊瘤胃体外发酵参数和氨基酸含量的影响

试验旨在研究不同蛋白原料对绵羊瘤胃体外发酵参数和氨基酸含量的影响。试验采用体外发酵法，以豆粕、棉仁粕、花生粕、菜籽饼、干酒糟及其可溶物（DDGS）和玉米胚芽饼为发酵底物，测定产气量、消化率、瘤胃液发酵参数、挥发性脂肪酸（VFA）及氨基酸含量。结果显示，杂粕各组的48 h产气量（GP）显著低于豆粕组（P<0.05）。玉米胚芽饼组的粗蛋白（CP）降解率显著高于豆粕组（P<0.05），棉仁粕、花生粕、菜粕、DDGS组显著低于豆粕组（P<0.05）。棉仁粕、菜粕组的氨态氮（NH3-N）含量显著高于豆粕组（P<0.05），棉仁粕组乙酸、丙酸、丁酸、异丁酸、异戊酸、总挥发性脂肪酸含量和乙丙比显著高于豆粕组（P<0.05），菜粕组的乙丙比显著高于豆粕组（P<0.05），玉米胚芽饼组的戊酸含量显著高于豆粕组（P<0.05）。花生粕、菜粕、DDGS组总脂肪酸含量显著高于豆粕组（P<0.05），棉仁粕组亮氨酸（Leu）、赖氨酸（Lys）、蛋氨酸（Met）、精氨酸（Arg）、谷氨酸（Glu）含量显著高于豆粕组（P<0.05），花生粕、菜粕、DDGS组的苏...     

Supplements Containing Escape Protein Improve Redberry Juniper Intake by Goats

Redberry juniper (Juniperus pinchotii Sudw.) is a common invasive plant species in west-central Texas. Goats will consume redberry juniper, but intake is limited by monoterpenoids found in the plant. Previous research has shown that goats will increase juniper intake through 1) conditioning and 2) protein supplementation. This study compared intake of juniper when goats received different protein supplements either with or without protein sources that are high in amino acids that escape digestion in the rumen. Recently weaned Boer-cross goats (n = 47) were randomly placed into five treatments. Treatments 1, 2, 3, and 4 received a protein supplement and juniper for 1 h daily for 14 d, along with a basal diet of alfalfa pellets (2% body weight). Treatment 5 received only a basal diet of alfalfa pellets and juniper. All supplements were formulated to be isonitrogenous (37% crude protein [CP]). Treatment 1 contained cottonseed meal (high CP escape value), treatment 2 contained cottonseed meal and distiller’s dried grain (higher CP escape value), treatment 3 contained soybean meal (low CP escape value), and treatment 4 contained soybean meal and distiller’s dried grain (moderate CP escape value). Refusals of juniper, supplements, and alfalfa were weighed daily to determine intake. Supplementation with 1) cottonseed meal, 2) soybean meal, or 3) soybean meal and distillers dried grain did not influence (P > 0.05) juniper intake. Conversely, goats supplemented with cottonseed meal and distiller’s dried grain ate more (P < 0.05) juniper than goats receiving only alfalfa, possibly because of increased escape of glucogenic amino acids. We contend that supplementation with feeds high in protein escape values should increase juniper intake on rangelands.     

Effects of season and inclusion of corn distillers dried grains with solubles in creep feed on intake, microbial protein synthesis and efficiency, ruminal fermentation, digestion, and performance of nursing calves grazing native range in southeastern North Dakota

Nine ruminally and duodenally cannulated (145 +/- 21 kg of initial BW; Exp. 1) and sixteen intact (181 +/- 36 kg of initial BW; Exp. 2), commercial, Angus, nursing, steer calves were used to evaluate the effects of advancing season and corn distillers dried grains with solubles in creep feed on intake, digestion, microbial efficiency, ruminal fermentation, and performance while grazing native rangeland. Calves were assigned to 1 of 2 treatments: a supplement containing 41% soybean meal, 26.25% wheat middlings, 26.25% soybean hulls, 5% molasses, and 1.5% limestone (control) or a supplement containing 50% corn distillers dried grains with solubles, 14.25% wheat middlings, 14.25% soybean hulls, 14% soybean meal, 5% molasses, and 1.5% limestone (CDDGS). Calves were offered supplement individually (0.45% of BW) once daily. Three 15-d collection periods occurred in June, July, and August. In Exp. 1, there were no differences in OM intake, or OM, N, NDF, or ADF digestion between control calves and those fed CDDGS. Forage and total OM intake increased (P < 0.03), whereas OM digestion decreased (P < 0.01), with advancing season. Duodenal microbial N flow (g/d) was not affected (P = 0.50) by treatment and increased linearly (P = 0.003) as season progressed. Calves consuming CDDGS had decreased (P < 0.01) ruminal acetate:propionate ratio, increased (P < 0.01) molar proportion of butyrate, and decreased (P < 0.001) molar proportions of isobutyrate and isovalerate. In Exp. 2, supplement OM intake (% of BW) was less for CDDGS compared with control calves, but there were no differences in performance or subsequent carcass composition between treatments. Inclusion of 50% corn distillers dried grains with solubles in a creep supplement for nursing calves produced similar results compared with a control creep feed based on soybean meal, soybean hulls, and wheat middlings.     

The effect of dietary nitrogen and protein on feed intake, nutrient digestibility, and nitrogen flux across the portal-drained viscera and liver of sheep consuming high-concentrate diets ad libitum

Our objectives were to determine the influences of supplemental nonprotein N or protein on feed intake, digestibility, and postabsorptive N metabolism in sheep fed a high-concentrate diet for ad libitum consumption. Nine Romanov-sired, crossbred wethers (13 mo old; 52 kg) were fitted with catheters in a mesenteric artery, mesenteric vein, portal vein, and hepatic vein. Wethers consumed a 95% concentrate diet ad libitum. Treatments consisted of control (no supplemental N; 6.6% CP) or supplemental urea (11.4% CP), soybean meal (SBM; 11.2% CP) or ruminally undegradable protein (BFM; 11.2% CP; 50:50 blood meal and feather meal). Intake or apparently digested intake of DM, OM, and energy did not differ between control and N-supplemented (P > 0.40), or between urea- and protein-supplemented (P > 0.40), but were greater (P < 0.05) in SBM- than in BFM-supplemented wethers. Intake and apparently digested intake of N were less (P < 0.01) in wethers fed the control diet than in those receiving N supplementation but were less (P = 0.03) in BFM- than in SBM-supplemented wethers. Neither portal nor hepatic venous blood flows differed (P > 0.15) among treatments. Net portal release and hepatic uptake of alpha-amino N and ammonia N and hepatic release of urea N were greater (P < 0.05) in wethers supplemented with N than in controls, but portal-drained viscera (PDV) uptake of urea N did not differ (P > 0.40) among diets. Splanchnic release of a-amino N and ammonia N did not differ from 0 or among diets (P > 0.10), but net release of urea N was less (P = 0.05) for control than for sheep receiving N supplementation. No differences (P > 0.10) in blood concentration within vessel or net flux across PDV, hepatic, or splanchnic tissues of alpha-amino N, ammonia N, or urea N were observed among wethers receiving supplemental N. Net uptake of oxygen by the PDV did not differ among diets, but hepatic uptake was less (P < 0.05) in control and urea-supplemented sheep than in sheep receiving SBM or BFM. These observations suggest that the source of supplemental N had no large effects on the overall N economy of the animals used in this study.     

Simultaneous measures of rates of ruminal digestion and passage of feeds for prediction of ruminal nitrogen and dry matter digestion in lactating dairy cows

Three ruminal-cannulated Holstein cows in early lactation were fed three diets, each containing different energy and protein supplements in two consecutive 3 X 3 Latin squares. Each supplement contained a combination of three different feedstuffs (ground corn, soybean meal and wheat mids; corn gluten feed, rolled oats and distiller's dried grains; ground barley, brewer's grains and cottonseed meal). Diets consisted of 30% corn silage, 10% alfalfa hay, 10% alfalfa haylage, 17.7% ground corn plus minerals and vitamins, with the remainder as supplemental feedstuffs individually marked for measurement of ruminal turnover and in situ digestion rates. An extra period at the end of each Latin square was used to measure ruminal turnover and in situ digestion of individual forages. Diet had no effect on dry matter intake or milk yield. Mean fractional turnover (per hour) rate, measured by labeling feedstuffs with cerium, samarium or lanthanum was .044, .048, .049, .043, .047, .046, .050, .047, .049, .037, .046 and .045 for corn, soybean meal, wheat mids, corn gluten feed, oats, distiller's dried grains with solubles, barley, brewer's dried grains, cottonseed meal, alfalfa hay, corn silage and alfalfa haylage (P greater than .1), respectively. In situ-predicted ruminal degradation of N weighted for rate of passage was 61.4, 67.0, 81.5, 74.8, 86.3, 71.0, 75.7, 52.1, 54.2, 60.8, 71.7 and 70.9% for respective feedstuffs (P less than .05). In comparison with mean literature values for in vivo-measured N degradability, mean literature value = 1.172 (in situ predicted) -9.73 (P less than .05, R2 = .51). Results are interpreted to indicate a tendency for overestimating ruminal N degradability by in situ methods in feedstuffs of low degradability, while underestimating degradability in more highly degraded feedstuffs. Estimates were 11 to 17 percentage units lower than literature values for alfalfa hay and haylage and 17 units lower than literature values for distiller's dried grains.     

提高生长肥育猪棉、菜籽饼饲粮蛋白质效率和饲养效果的研究

<正> 前言 蛋白质饲料不足,是影响养猪生产的原因之一。然而,据1982年统计,我省年产棉、菜籽饼共4.7亿公斤,但饲用量不到5％。其原因之一是,含有毒物,蛋白质质差和适口性低,用于养猪仅能得到低下的饲养效果。 据报告:用棉饼和菜饼或加上大豆饼配合饲用,可限其毒物于安全水平和改进氨基酸的平衡性(1961年Abrams;1982年Hodson等);补充限制性氨基酸是提高“两饼”饲效的有效方法,也有增加采食量的作用     

饲粮蛋白质水平和棉籽粕取代豆粕对肉牛育肥的影响

本试验在满足肉牛营养需要的基础上,采用棉籽粕替代饲粮中的豆粕,形成不同蛋白质水平和成本的饲粮,旨在探讨饲粮蛋白质水平和棉籽粕替代豆粕对肉牛育肥的影响,同时为降低肉牛育肥成本和提高育肥效果提供依据.试验选用年龄(平均年龄为28月龄)、体重[初始均重为(678±122)kg]相近的健康杂交一代阉牛(日本和牛♂×鲁西黄牛♀)40头,随机分成4个试验组,每组10头牛.预试期为15 d,正试期240 d.结果表明:蛋白质水平为14.8％的饲粮组试验牛的日增重比蛋白质水平为12.8％的饲粮组提高18.57％(P ＞0.05).与饲喂蛋白质水平为12.8％的饲粮相比,饲喂蛋白质水平为14.8％的饲粮可以显著或极显著提高肉牛的屠宰率、净肉率、肋部脂肪厚、背膘厚(P＜0.05或P＜0.01),而对肉牛的胴体产肉率、眼肌面积、高档肉块占活重比例、肉骨比影响不显著(P＞0.05).同等蛋白质水平下,用棉籽粕全部或部分替代豆粕对肉牛日增重及各项屠宰性能指标的影响均不显著(P＞0.05),但棉籽粕组饲粮单价、肉牛每千克增重成本都低于豆粕组.由此得出,在肉牛育肥后期可以用棉籽粕替代豆粕,以降低成本.目前我国《肉牛饲养标准》(2004)推荐的肉牛育肥所需的蛋白质水平低于本试验用杂交一代阉牛(日本和牛♂×鲁西黄牛♀)的需要.     

反刍家畜常用饲料蛋白质和氨基酸瘤胃降解特性和小肠消化率评定研究

本试验探讨了常用饲料在瘤胃的降解特性及非降解饲料的小肠消化率,旨在为研究反刍动物的营养平衡和消化规律及科学配制日粮提供依据。试验选用3头装瘤胃瘘管和十二指肠瘘管的肉牛,采用尼龙袋法研究反刍动物常用饲料粗蛋白质和氨基酸瘤胃降解参数和表观小肠消化率。结果表明,在本试验中粗蛋白质降解率由低到高的顺序为:酒糟蛋白、黄玉米、羊草、玉米胚芽饼、菜粕、棉粕、豆粕、花生饼、啤酒糟、苜蓿、米糠、小麦麸;总氨基酸瘤胃降解率由低至高的顺序依次为:酒糟蛋白、黄玉米、羊草、玉米胚芽饼、菜粕、豆粕、棉粕、啤酒糟、花生饼、苜蓿、米糠、小麦麸。除花生饼、酒糟蛋白和黄玉米外,粗蛋白质和总氨基酸的有效降解率差异不显著(P>0.05)。粗蛋白质的表观小肠消化率由低至高的顺序依次为:苜蓿、羊草、米糠、小麦麸、啤酒糟、玉米胚芽饼、棉粕、菜粕、玉米、酒糟蛋白、花生饼、豆粕;总氨基酸的小肠消化率由低至高的顺序依次为:羊草、苜蓿、米糠、小麦麸、啤酒糟、玉米胚芽饼、菜粕、棉粕、花生饼、玉米、酒糟蛋白、豆粕。由此可见,不同的饲料瘤胃降解特性是不同的,并且为小肠提供的各种可吸收氨基酸潜力也是不同的。     

2015年山东省肉鸡饲料原料中重金属污染情况调查及风险评估

本试验旨在调查2015年山东省肉鸡饲料原料中砷、铅、镉、铬和汞元素的污染情况,评估饲料原料的污染风险。试验收集烟台市莱阳、威海市文登、青岛市莱西、潍坊市诸城、日照市莒县、临沂市沂水、德州市夏津等地不同饲料生产厂家使用的8种饲料原料,包括玉米、豆粕、麸皮、花生粕、棉籽粕、玉米蛋白粉、干酒糟及其可溶物( DDGS)和微量元素预混料,应用电感耦合等离子体原子发射光谱法( ICP-AES)检测镉、铅和铬元素的含量,应用原子荧光光谱法( AFS)检测砷和汞元素的含量,计算检出率、平均含量、超标率、最高含量与平均含量比值( HC/AC)和离散系数。结果表明：饲料原料中砷、铅、镉、铬和汞元素的检出率分别为32.29%、7.29%、12.50%、100.00%和100.00%;阳性样品中平均含量分别为0.21、1.27、2.12、3.48和0.02 mg/kg,超标率分别为0.00、1.04%、1.19%、54.76%和9.52%;微量元素预混料中砷、铅和镉元素,棉籽粕中铬元素及花生粕中汞元素的HC/AC最大,微量元素预混料中镉元素、花生粕中汞元素、豆粕中砷元素及棉籽粕中铅和铬元素离散系数最大。综上所述,肉鸡饲料原料中铬和汞元素污染严重;微量元素预混料中砷、镉、铬和铅元素、棉籽粕中铬和铅元素、花生粕和豆粕中汞元素易出现严重污染,因此建议制定预混料和饼粕类饲料中多种重金属元素的限量标准。     

Effects of increasing dried distillers’ grains with solubles and non-starch polysaccharide degrading enzyme inclusion on growth performance and energy digestibility in broilers

Two experiments were conducted to examine the effects of non-starch polysaccharide degrading enzyme on broiler performance and ileal nutrient digestibility in diets containing dried distillers’ grains with solubles, as well as evaluate non-starch polysaccharide degrading enzyme inclusion in low energy diets with dried distillers’ grains with solubles on performance and carcass yield. Experiment 1 was a 4 (dried distillers’ grains with solubles level of 0, 5, 10, and 15%) x 2 (with and without enzyme) factorial design in battery-reared broilers for 21 d; body weights and feed intake were determined weekly. On day 22, ileal contents were collected to determine digestibility of energy and nitrogen. The second experiment was a 48 d floor pen trial utilizing three dietary treatments: positive control, negative control (positive control, negative control less 132 kcal/kg ME), and a negative control + non-starch polysaccharide degrading enzyme inclusion. Diets included dried distillers’ grains with solubles at 2.5 to 10%. In Experiment 1, BW decreased (P < 0.05) with 15% dried distillers’ grains with solubles inclusion as compared to the control. The FCR was also increased (P < 0.05) with 15% dried distillers’ grains with solubles inclusion as compared to all other diets through 14 d. Inclusion of dried distillers’ grains with solubles reduced (P < 0.05) ileal digestible energy at 10 and 15% inclusion and inclusion of non-starch polysaccharide degrading enzyme increased (P < 0.05) ileal digestible energy. Increased energy and nitrogen digestibility coefficients (P < 0.05) were observed at all dried distillers’ grains with solubles inclusion levels with non-starch polysaccharide degrading enzyme inclusion except for the 10% inclusion rate. In Experiment 2, non-starch polysaccharide degrading enzyme in the negative control diet increased BW compared to the negative control at all observed time points at each phase (P < 0.05). Additionally, non-starch polysaccharide degrading enzyme in the negative control diet reduced mortality corrected FCR through the grower phase. Non-starch polysaccharide degrading enzyme inclusion in the negative control diet resulted in comparable live weights, carcass weights, breast filets, and tenders to the positive control diet; however, fat pad was reduced compared to the positive control (P < 0.05). These data confirm that elevated levels of dried distillers’ grains with solubles in starter diets can negatively impact digestibility and performance of broilers and the inclusion of an non-starch polysaccharide degrading enzyme can increase nutrient digestibility and improve broiler performance in low energy dried distillers’ grains with solubles containing diets.