猪饲粮中蛋白质含量宜满足需要而避免过量

在满足猪对必需氨基酸需要量的同时,避免蛋白质的过量饲喂不仅经济,而且有利于营养吸收,减轻对环境的压力.     

精确蛋白质日粮

成本控制已经影响了美国人对猪饲料中蛋白质含量的考虑,而现在对于环境问题的考虑也正在对欧洲生产着类似的影响。无论在美国还是在欧洲,猪日粮中的粗蛋白含量一直随着日粮中氨基酸的添加而下降。     

低蛋白质日粮饲喂保育猪、肥育猪使用效果

低蛋白质日粮即按NRC（美国饲养标准）推荐标准配制的日粮蛋白质基础上降低2%～4%粗蛋白。主要应用＂理想蛋白＂原理,通过添加赖氨酸、苏氨酸、蛋氨酸、色氨酸等必需氨基酸,可以使日粮蛋白质的利用大大提高,从而降低蛋白原料（鱼粉、     

猪的日粮养分供应量

关于不同基因型和不同环境条件下猪营养需要量,人们众说纷纭。尽管猪在基因型和所处环境条件不同时的营养需要量毫无疑问确实是存在差别的,但常常缺乏根据严格受控条件下精心进行的实验提出的营养推荐量。表1、表2、表3和表4代表了笔根据目前已发表的实验结果提出的养分供应量。     

日粮中不同的平衡蛋白质水平对生长肥育猪生长性能和胴体组威的影响

目前,人们常通过基因选择和营养调控来最大化地提高猪的瘦肉率。一般地,提高日粮营养水平,特别是适宜的氨基酸和能量水平,可提高猪的瘦肉率。氨基酸需要量可受到日粮蛋白质水平、日粮能量浓度、环境温度、性别和猪的瘦肉生长潜能等诸多因素的影响。赖氨酸是猪的第一限制性氨基酸。通常,首先要确定日粮中赖氨酸的需要量,然后以理想蛋白质理论为基础,去考虑其他必需氨基酸的需要量与赖氨酸需要量的比值,从而得出平衡蛋白质日粮。因此,平衡蛋白质日粮中所有必需氨基酸保持较适宜的水平,以满足动物机体的生理需要,和减少氨基酸的损失。     

在猪日粮中充分利用植物蛋白质

欧盟委员会 2 0 0 0年底关于在饲料中禁用某些动物蛋白质制品的决定 ,从技术上和经济上对进行猪、禽饲料配合的商业营养师提出了相当严峻的挑战。有些欧洲国家还已经自主决定将鱼粉包括在禁用之列 ,或者因靠近反刍畜饲料生产场地而担心其储存问题故将其剔除出生产多畜种饲料的饲料厂。与此同时 ,许多饲料生产商还往往不用动物脂肪而改用植物油脂以图在越来越严格的监督下增强行业的自信。这些措施的结果是增强了在日粮中对各种植物蛋白质的依赖 ,而究竟选用哪些原料就取决于相对成本和其供应量充足与否。这些原料的纤维含量较高 ,其中蛋白质…     

猪的日粮营养供给量

1 表内所列猪体重以Ib计。推荐的蛋白质和氨基酸供给量的条件是玉米-大豆粕日粮,其中分别含有1560和1500kcal/IbDE(可消化能)和ME(代谢能)。对高瘦肉遗传型的上市屠宰用猪,在计算氨基酸需用量时用的是理想比率(相对于赖氨酸)。 2 公猪在生长和肥育阶段应分别进食含0.90％和0.75％赖氨酸日粮。成年公猪尚未制定特殊的要求。妊娠期小母猪饲以全价日粮,成年公猪日粮也是全价的。     

配制低蛋白质日粮的必要性及其注意事项

近几十年来．猪的氨基酸营养一直是各国学者研究的热点。一方面由于全世界范围内蛋白质资源的日趋紧张．另一方面由于日粮氨基酸不平衡引发粪尿氮大量排放而引起严重的环境污染。在成本和环保的双重压力下,低蛋白质日粮成为自20世纪90年代以来欧美动物营养领域的研究热点。因此,在充分满足动物营养需要的情况下．采用以理想氨基酸模式为基础,按照真可消化氨基酸需要量合理配制低蛋白质日粮,对降低日粮蛋白质水平及减少环境污染意义重大。     

猪实用饲养技术──基础、需要量和日粮设计

营养学家和配方师一直在寻求组合多种原料以提高猪饲料质量及利润的方法。通常他们利用研究资料和新饲料名目来修订和调整配方。计算机模型化的新版NRC猪需要量标准,涉及对不同类型猪特定营养需要量的确定,也可以对特定猪群及不同基因型猪营养需要进行确定。新版NRC猪需要量标准的其它主要优点是：可利用大量饲料原料配制经济有效的猪日粮;能更精确地确定日粮中各原料特别是副产品原料的真实价值;饲料及其营养行为描述方面的新进展,也可用于改进日粮设计。最佳日粮配合取决于对各种目标饲料原料可利用蛋白质及能量含量的精确描述。…     

DDGS在猪日粮中的潜在应用价值

由于蛋白质含量低和纤维含量高,谷物中蒸出酒精或酒精饮料后的残渣大部分都用来饲喂肉牛和奶牛。然而,由于乙醇产量的增加和生产的现代化,DDGS在家禽和猪饲料中的应用与日俱增。Chad Hastad解释了应用DDGS的一些益处。     

仔猪饲料中的植物蛋白因加工而产生的变化

温度不是饲料加工过程中需要考虑的唯一因素,湿度、加工时间和颗粒大小都会有变化,并最终都会影响饲料的营养价值。随着更多的植物蛋白添加到猪日粮中,这一问题越发严重,准确地说,在大豆的应用中就有此问题。     

DDGS在猪日粮中的应用

干酒糟及其可溶物（DDGS）是推向饲料市场的相对较新的饲料原料,不过所谓的“新”主要指在欧洲和亚洲的应用前景。在美国,2005年大约有900万吨的DDGS被当作饲料使用,其中75％～80％用于反刍动物,大约20％用于猪日粮。     

Protein supply in organic broiler diets

Abstract

Organic feed legislation, long-rearing periods and high requirements of sulphur-rich amino acids (AAs) complicate the composition of a well-balanced organic diet for broilers. To evaluate the effect of protein and AA composition, three different diets were fed to 180 Ross broilers, divided over 45 pens. The diets comprised a low crude protein (CP) and AA diet, a high CP diet aiming at AA levels used in conventional production and a low protein diet supplemented with lysine, methionine and threonine up to levels of the high protein diet. Chickens were immunologically challenged with an inactivated infectious bursal disease (IBD) vaccine; antibody titres, heterophil/lymphocyte (H/L) ratios, lymphoid organ weights and digestibility coefficients were recorded. In general, bird performance improved with increasing dietary CP and AA levels. Dietary treatments did not significantly affect any of the measured immune or stress-related parameters.     

植酸酶在含有玉米副产品猪日粮中的效果

因为即使是不添加微生物型植酸酶,干酒糟副产品中的磷也可被猪充分地消化,所以添加植酸酶对提高这些成分中磷的消化率仅能产生极为有限的作用,因此并不经济。     

Evaluation of soy protein concentrates in nursery pig diets

Four experiments were conducted with 730 weanling pigs to determine the effects of soy protein concentrate (SPC) in diets for weanling pigs. Experimental diets were fed from d 0 to 14 postweaning and a common diet was fed from d 15 to 28 for Exp. 1, 2, and 3; experimental diets were fed from d 0 to 7 postweaning in Exp. 4. In Exp. 1, the 4 experimental diets included 1) a 0% soybean meal (SBM) diet containing animal protein sources; 2) a 40% SBM diet; or a 28.55% SPC (replacing the 40% SBM on a total Lys basis) diet from 3) source 1, or 4) source 2. Pigs fed diets containing either animal protein or 40% SBM had greater ADG and ADFI (P <0.05) than pigs fed either SPC source. In Exp. 2, the 5 experimental treatments included diets 2, 3, and 4 from Exp. 1, along with 14.28% SPC from each SPC source used in Exp. 1 (replacing half of the total Lys from the 40% SBM diet). From d 0 to 14 and d 0 to 28, the SPC source x level interaction was significant for ADG (P <0.01) and was a tendency for ADFI (P <0.07). Replacing SBM with SPC from source 1 did not affect pig performance. However, replacing SBM with SPC from source 2 resulted in an improvement (quadratic, P <0.05) in ADG for pigs fed the diet containing 14.3% SPC, but resulted in no benefit from replacing all the SBM with SPC. Replacing SBM with SPC from either source improved G:F (quadratic, P <0.01), with the greatest G:F observed for pigs fed the diets with 14.3% SPC. Experiment 3 evaluated increasing levels of source 2 SPC, with treatments consisting of 1) 0% (40% SBM); 2) 7.14%; 3) 14.28%; 4) 21.42%; and 5) 28.55% SPC. There was a tendency for increased ADG (quadratic, P <0.06) and increased ADFI (quadratic, P <0.04) as inclusion of SPC in the diet increased. The gain-to-feed ratio improved (linear, P <0.01) as the SPC level in the diet increased. Inclusion of approximately 14 to 21% SPC from source 2 maximized pig performance. In Exp. 4, pigs were offered a choice of consuming the diets containing 40% SBM or 28.6% SPC from source 2. Daily feed intake was greater (P <0.0001) for the SBM diet (186 g/d) than for the SPC diet (5 g/d). Our results suggest that replacing a portion, but not all, of the high-SBM diet with SPC from source 2, but not from source 1, improves pig performance. The poor intake of pigs fed high levels of SPC may indicate a palatability problem, thus limiting its inclusion in nursery pig diets.     

Measurements of the acid-binding capacity of ingredients used in pig diets

: Some feed ingredients bind more acid in the stomach than others and for this reason may be best omitted from pig starter foods if gastric acidity is to be promoted. The objective of this study was to measure the acid-binding capacity (ABC) of ingredients commonly used in pig starter foods. Ingredients were categorised as follows: (i) milk products (n = 6), (ii) cereals (n = 10), (iii) root and pulp products (n = 5), (iv) vegetable proteins (n = 11), (v) meat and fish meal (n = 2), (vi) medication (n = 3), (vii) amino acids (n = 4), (viii) minerals (n = 16), (ix) acid salts (n = 4), (x) acids (n = 10). A 0.5 g sample of food was suspended in 50 ml distilled de-ionised water with continuous stirring. This suspension was titrated with 0.1 mol/L HCl or 0.1 mol/L NaOH so that approximately 10 additions of titrant was required to reach pH 3.0. The pH readings after each addition were recorded following equilibration for three minutes. ABC was calculated as the amount of acid in milliequivalents (meq) required to lower the pH of 1 kg food to (a) pH 4.0 (ABC-4) and (b) pH 3.0 (ABC-3). Categories of food had significantly different (P < 0.01) ABC values. Mean ABC-4 and ABC-3 values of the ten categories were: (i) 623 (s.d. 367.0) and 936 (s.d. 460.2), (ii) 142 (s.d. 79.2) and 324 (s.d. 146.4), (iii) 368 (s.d. 65.3) and 804 (s.d. 126.7), (iv) 381 (s.d. 186.1) and 746 (s.d. 227.0), (v) 749 (s.d. 211.6) and 1508 (s.d. 360.8), (vi) 120 (s.d. 95.6) and 261 (s.d. 163.2), (vii) 177 (s.d. 60.7) and 1078 (s.d. 359.0), (viii) 5064 (s.d. 5525.1) and 7051 (s.d. 5911.6), (ix) 5057 (s.d. 1336.6) and 8945 (s.d. 2654.1) and (x) -5883 (s.d. 4220.5) and -2591 (s.d. 2245.4) meq HCl per kg, respectively. Within category, ABC-3 and ABC- 4 values were highly correlated: R2 values of 0.80 and greater for food categories i, iv, v, vi, vii and viii. The correlation between predicted and observed ABC values of 34 mixed diets was 0.83 for ABC-4 and 0.71 for ABC-3. It was concluded that complete diets with low ABC values may be formulated through careful selection of ingredients. The final pH to which ABC is measured should matter little as ABC-3 and ABC-4 are highly correlated.