Feed preference in pigs: effect of cereal sources at different inclusion rates

The palatability of different cereals was studied in 2 two-way choice (preference) experiments using pigs of 56 d of age and 17 kg of BW. In Exp. 1, the effect of 24 cereals vs. a common reference diet containing white rice on feed preference in pigs was studied. Pigs were offered free choice between the reference diet and a diet with the cereal under study for 4 d. Barley, corn (2 sources), wheat, cassava meal, biscuit meal, rye, sorghum, and 1 source of oats were tested at inclusion rates of 300 and 600 g x kg(-1). Short-grain rice (whole, brown, or extruded white), long-grain white rice (raw and cooked), extruded barley, extruded corn, extruded wheat, oats (2 sources), thick rolled oats, cooked oats, and naked oats (raw, extruded, or micronized) were tested at inclusion rates of 150, 300, and 600 g x kg(-1). Relative preference of cereals (% of total feed intake) was affected by type of cereal and by rate of inclusion. The diets containing extruded rice (150 g x kg(-1)), extruded naked oats (150, 300, and 600 g x kg(-1)), or naked oats (150 and 300 g x kg(-1)) were preferred (P < 0.05) by pigs to the reference diet. However, the reference diet was preferred (P < 0.05) to the diets containing 150, 300, and 600 g x kg(-1) of cooked long-grain rice, oats, or cooked oats, 300 and 600 g x kg(-1) of extruded wheat, wheat, corn, sorghum, or unhulled short-grain rice, and 600 g x kg(-1) of thick rolled oats, extruded corn, rye, extruded barley, micronized naked oats, barley, cassava, or biscuit meal. Extrusion improved (P < 0.05) preference values for corn and naked oats by pigs, but had no effect on barley, rice, or wheat. In Exp. 2, the preferences of pigs for oats and barley were studied using mash and pelleted diets. Diet form did not affect preference in oats diets. However, for barley, greater preference values were obtained when measured in pelleted form compared with mash form. Additionally, direct 2-way choices were also performed between oats and barley diets and between diets presented in mash and pelleted forms. Pigs preferred barley to oats, and preferred diets presented in pelleted form to those presented in mash form. In conclusion, cereal type, inclusion rate, and diet form affected feed preference in pigs. Using cereals with greater preference values may contribute to the formulation of more palatable feeds, which enhance feed intake of piglets at critical stages such as weaning time.     

原料粒度对家禽消化和生产性能的影响

饲料工业很少关注蛋白类原料（如豆粕、肉粉等）的粒度，因其在出厂时已经粉碎，但需要控制谷物等的粒度。     

Feed preference in pigs: effect of selected protein, fat, and fiber sources at different inclusion rates

Three double-choice feeding experiments were conducted to study the effect of different feedstuffs on feed preference in pigs. Fifteen protein sources, 6 fat sources, and 3 fiber sources were evaluated in Exp. 1, 2, and 3, respectively. Pigs were offered a series of double choices between a common reference diet and the diet with the ingredient under evaluation. The reference diet contained a soybean meal product with 56% CP (SBM-56), sunflower oil, and wheat bran, which were considered as the feedstuffs of reference for the protein, fat, and fiber sources, respectively. Preference, expressed as percentage of the tested diet to total feed intake, was affected by feedstuff nature and by its inclusion rate. In Exp. 1, feeds with fish meal at 50 and 100 g·kg?1, dried porcine hydrolyzed protein at 50 g·kg?1, and lupine, soybean meal with 44% CP, and dried skim milk at 100 g·kg?1 were preferred (P < 0.05) to the reference feed with SBM-56. On the contrary, relative to SBM-56, an avoidance (preference less than 50%) was observed for potato protein at all inclusion rates tested, rapeseed meal and acid milk whey at 100 and 200 g·kg?1, and dried porcine hydrolyzed protein, soybean protein concentrate, wheat gluten, and sunflower meal at 200 g·kg(-1). The storage of dried skim milk, soybean protein concentrate, and potato protein for 10 mo resulted in a reduction (P < 0.001) of their preference values. In Exp. 2, the feed with palm oil (at 30 g·kg?1) was preferred (P < 0.05), whereas feeds with linseed oil (at 30 and 100 g·kg?1) and soybean oil (at 100 g·kg?1) were avoided (P < 0.05) when contrasted with the reference feed with sunflower oil. Finally, in Exp. 3 diets with dehydrated alfalfa and sugar beet pulp at 130 g·kg?1 had a reduced (P < 0.05) preference compared with the reference diet with wheat bran. It is concluded that feedstuff nature, inclusion rate, and freshness affect feed preference in pigs. Feedstuff preferences should be taken into account during diet formulation, particularly at critical stages such as immediately after weaning.     

饲料检测与饲料安全

１我国饲料质量发展基本概况中国饲料工业是迅速发展起来的一个新兴行业。２０世纪７０年代以来，从无到有，从小到大。据统计，２０００年全国饲料生产企业１．２万多家，产量７５００万吨，产值２０００亿元，已成为世界第二大饲料生产国。为了保证饲料工业的健康稳步发展，从１９８４年开始，国家和地方投入大量的人力物力，用于我国饲料监测体系的建设。到２０００年为止，全国饲料质量监督检验体系的法规体系、质检体系和标准化体系已基本建成。法规体系的逐步完善，标志我国饲料质检工作有法可依。《中华人民共和国产品质量法》、《中…     

饲料安全与饲料监管

近年来,由饲料安全问题引发食品安全问题的事件时有发生,且有愈来愈严重的趋势。继上世纪末欧洲发生“二恶英”、“疯牛病”饲料污染事件以来,本世纪初又发生了“除草醚”、“甲孕酮”饲料污染事件。我国至今虽未发现有“二恶英”、“疯牛病”的污染,但“瘦肉精”等违禁药品的添加使用,已导致十多起上千人中毒事件的发生,非法使用安定、氯丙嗪、安眠酮、碘化酪蛋白、抗生素的发酵残渣等违禁物品的现象依然存在;因氯霉素、磺胺类药物残留导致畜禽水产品出口屡屡受挫;饲料中添加有机砷和高剂量使用铜、锌,除造成直接的环境污染外,还通过食物链…     

Effect of oat particle size on energy and nutrient utilization in growing pigs

An experiment was conducted to determine the energy content of oats and to investigate the effects of oat particle size on nutrient and energy balance in growing pigs. Eighteen barrows (23.56 ± 0.94 kg initial body weight) were randomly assigned to one of the three dietary treatments with six replicates per treatment. Whole oats were ground with a hammermill fitted with 4.8- and 3.2-mm screens to make coarse and medium particle size oats, respectively. Medium oats were further ground with a rotary steel cutting grinder fitted with a 2.0-mm screen, and the further ground oats were mixed with medium oats in a 1:3 ratio to make fine oats. Three experimental diets consisted of 96.3% of the coarse, medium, or fine oats as a sole source of energy were used. Pigs were fed diets for 16 d, including 10 d for adaptation and 6 d for total fecal and urine collection. Pigs were then moved into indirect calorimetry chambers to determine 24-h heat production and 12-h fasting heat production. All data were analyzed using the MIXED procedure of SAS with the individual pig as the experimental unit. The geometric mean particle sizes for coarse, medium, and fine oats were 765, 619, and 569 μm, respectively. Pigs fed the medium oats diet tended to have (P < 0.10) greater apparent total tract digestibility (ATTD) of starch, neutral detergent fiber, and gross energy than those fed coarse oats diet. The medium oats diet contained greater (P < 0.05) digestible energy (DE), metabolizable energy (ME), and net energy (NE) than the coarse oats diet. Pigs fed the fine oats diet had lower (P < 0.05) ATTD of Ca and P than those fed the coarse oats diet. The DE, ME, and NE contents of fine oats were comparable with those of coarse oats. The determined NE contents for coarse, medium, and fine oats were 2,335, 2,615, and 2,521 kcal/kg on a dry matter basis, respectively. The NE content in medium oats was greater (P < 0.05) than the NE values predicted using published equations. In conclusion, it was suggested to grind whole oats for 619 μm concerning energy utilization. Further grinding to 569 μm reduces Ca and P digestibility.     

Enzyme supplementation and particle size of wheat in diets for nursery and finishing pigs

Three experiments were conducted to determine the effects of enzyme supplementation and particle size of wheat-based diets on growth performance and nutrient digestibility in nursery and finishing pigs. In Exp. 1, 180 weaned pigs (5.7 kg and 21 d of age) were fed diets in a 35-d growth assay without or with a Trichoderma longibrachiatium enzyme product (4,000 units of xylanase activity per gram of product) and with wheat ground to mean particle sizes of 1,300, 600, or 400 microm. Enzyme supplementation had no effect on ADG or gain/feed (P > 0.32), but there was a trend (P < 0.10) for greater digestibility of DM (d 6) in enzyme-supplemented diets. A particle size of 600 microm supported the greatest overall gain/feed (quadratic effect, P < 0.01). An interaction of enzyme supplementation with particle size occurred; gain/feed was improved (P < 0.01) with enzyme supplementation at the coarse (1,300 microm) particle size but not when the wheat was ground to 600 or 400 microm. In Exp. 2, 160 finishing pigs (67 kg) were fed a diet without or with the same enzyme used in Exp. 1 and wheat ground to 1,300 or 600 microm. No interactions occurred between enzyme supplementation and particle size of the wheat (P > 0.15). However, there were trends for greater gain/feed (P < 0.10) during the 67- to 93-kg phase of the experiment and for greater digestibility of DM (P < 0.10) and N (P < 0.07) with enzyme supplementation. When particle size was reduced from 1,300 to 600 microm, gain/feed was improved (P < 0.03) for the 93- to 114-kg phase of the growth assay, and digestibilities of DM (P < 0.02) and N (P < 0.04) were greater. In Exp. 3, 160 finishing pigs (63 kg) were given diets without or with the enzyme product and wheat ground to 600 or 400 microm. Enzyme supplementation improved ADG (P < 0.04) in the 90- to 115-kg phase but otherwise did not affect growth performance, carcass measurements, or stomach lesions. A particle size of 400 microm increased overall gain/feed (P < 0.04), digestibilities of DM and N (P < 0.01), and development of stomach lesions (P < 0.01). In conclusion, pigs did not benefit consistently from enzyme supplementation. However, wheat particle sizes of 600 and 400 microm supported the best overall performance in nursery and finishing pigs, respectively.     

饲料颗粒大小对鸡生产性能和饲料消化能力的影响

<正>饲料颗粒的大小对鸡来说至关重要,因为鸡主要通过饲料颗粒的大小来挑食。因此,要确保鸡采食充足,就必须将饲料加工成最合适的颗粒大小。但是企业在加工制造饲料时,历来很少重视蛋白质粉料的颗粒大小,比如大豆粉料、动物蛋白粉料。在饲料加工上,     

Effect of feed particle size and feed processing on morphological characteristics in the small and large intestine of pigs and on adhesion of Salmonella enterica serovar Typhimurium DT12 in the ileum in vitro

A 2 x 2 factorial experiment with pigs was undertaken to investigate the effect of particle size (fine and coarse) and feed processing (pelleted and nonpelleted) on morphological characteristics in the small intestine, cecum, and colon of pigs and on the adhesion of Salmonella enterica serovar Typhimurium DT12 to the ileum in vitro. Ninety-six pigs (average BW = 33 +/- 7 kg) were fed the experimental diets. After 4 wk, 24 pigs were selected (six pigs per diet) and euthanized, and tissue samples were taken from the mid and distal small intestine, cecum, and distal colon. The effects of particle size and feed processing on villus height and crypt depth in the small intestine were minor. Feeding coarse diets increased (P = 0.05) the crypt depth in the colon. The crypt depth was 420 +/- 12 and 449 +/- 12 microm in pigs fed finely and coarsely ground feed, respectively. Pigs fed pelleted diets had a larger (P = 0.01) staining area for neutral mucins, as well as for acidic and sulfomucins on the villi of the distal small intestine than pigs fed nonpelleted diets. The area was 41, 46, and 33% larger for neutral, acidic, and sulfomucins, respectively. The mucin-staining areas of the crypts in the cecum and the colon were not affected by the experimental diets. Examination of lectin binding characteristics of the distal small intestine and the cecum did not reveal any differences between the experimental diets. Using a pig intestine organ culture model, Salmonella adhered less (P < 0.05) to the ileal tissue of pigs fed the nonpelleted diets than to those fed pelleted diets; the adherence was 60% less in these pigs. Results of this study suggest that pigs fed pelleted diets secrete mucins that are capable of binding Salmonella enterica serovar Typhimurium DT12 and thereby allowing for colonization. Therefore, pigs fed a nonpelleted diet are better protected against Salmonella infections than pigs fed a pelleted diet.     

Eliminating Salmonella in pigs starts with clean feed

欧盟食品安全局(European Food Standards Agency,EFSA)在成功控制养禽业中的沙门氏菌污染后,开始关注养猪业的沙门氏菌污染问题,因为其估计,欧洲大约10％ ～20％的人感染沙门氏菌病例是由食用猪肉产品引起的.     

饲料加工工艺与饲料质量

１粉碎工艺 １．１粒度与混合均 匀度粉碎后的物料 表面积增大，有利于 粉体混合均匀，随着 单位体积内粒子数的 增加，混合物的变异 系数减少。 有研究发现，玉 米经粉碎过１．７ｍｍ 筛后，只需混合１．５ ｍｉｎ即可使变异系数 小于１０％，而粗粉碎 （６．４ｍｍ）的玉米混合 ３ｍｉｎ变异系数大于 １０％，而小于２０％。 无论使用卧赋或立式 螺带混合机，混合效 果均不理想。 １．２粒度与颗粒质 量粒度是影响颗粒 质量的重要因素。一 般认为，压粒用的物料以粗中细比例适当为好。过多的粗物料，影响颗粒的成形，因为细物料可增加粉体…     

从清洁饲料入手清除猪群中的沙门氏菌

欧盟养猪业应该研究养禽业是如何降低沙门氏菌感染的风险。     

Effects of soybean meal particle size on growth performance of nursery pigs

We used 360 nursery pigs (35 +/- 3 d of age) in two 21-d growth assays to determine the effects of soybean meal particle size on growth performance. In both trials, there were six pigs per pen and 10 pens per treatment. Pigs were weaned on d 21 and fed the same phase I diet for 7 d after weaning, followed by a phase II diet from d 7 to 14. On d 14, all pigs were weighed and randomly allotted to one of three dietary treatments. Experimental diets contained 61.9% corn, 34.4% soybean meal, and 3.7% vitamins and minerals. In Exp. 1, 90 barrows and 90 gilts (9.2 +/- 2.3 kg BW) were fed diets containing extruded-expelled soybean meal ground to 965, 742, or 639 microm, which resulted in whole-diet particle sizes of 728, 719, and 697 microm, respectively. Reducing extruded-expelled soybean meal particle size from 965 or 742 to 639 microm in the diet did not affect (P > 0.10) ADG (541, 538, and 542 g/d), ADFI (886, 875, and 855 g/d; as-fed basis), or gain:feed ratio (0.61, 0.61, 0.64), respectively. In Exp. 2, 90 barrows and 90 gilts (9.9 +/- 2.6 kg BW) were fed diets containing solvent-extracted soybean meal ground to 1,226, 797, or 444 microm, which resulted in whole-diet particle sizes of 732, 681, and 629 microns, respectively. Like Exp. 1, reducing particle size of solvent-extracted soybean meal did not affect (P > 0.10) ADG (482, 487, and 484 g/d), ADFI (738, 742, and 736 g/d; as-fed), or gain:feed (0.65, 0.65, and 0.65). Reducing particle size of extruded-expelled soybean meal or solvent-extracted soybean meal increased the angle of repose (maximum degree at which a pile of material retains its slope), indicating that as particle size decreased, flowability characteristics decreased. However, the angle of repose of the complete diets was greater than that for the soybean meals, which indicates that decreasing the particle size of soybean meal had minimal effects on flow characteristics of the complete diet. Previous research has shown that decreasing grain particle size improves digestibility and feed efficiency, and decreased soybean meal particle size has resulted in improved amino acid digestibility. However, the results of our experiments suggest decreasing particle size of either extruded-expelled soybean meal or solvent-extracted soybean meal does not affect nursery pig growth performance.     

Effect of rostrocaudal mobility of the mandible on feed digestibility and fecal particle size in horses

OBJECTIVE: To evaluate the effect of rostrocaudal mobility (RCM) of the mandible during extension and flexion of the atlanto-occipital joint on weight gain, feed digestibility, and fecal particle size in horses. DESIGN: Randomized controlled trial. ANIMALS: 34 pregnant mares housed in 1 barn. PROCEDURES: Horses were randomized into a treatment (n = 17) or control (17) group. All horses were sedated, and the distance between the rostral portions of the upper and lower incisor arcades was determined during extension and flexion of the atlanto-occipital joint; mandibular RCM was calculated as the difference between these values. In the treatment group, measurements were made after dental floating. Body weight was recorded 1 day before dental floating and at intervals after mandibular RCM determination for a period of 24 weeks. Feces were collected from each horse during two 5-day periods. Samples of feed and feces were analyzed to determine feed digestibility; particle size analysis was performed on dried fecal samples. RESULTS: Data obtained from each group of horses revealed that RCM of the mandible did not affect weight gain, feed digestibility, or particle size in feces; there were no differences among breeds. Controlling for age and number of dental lesions did not significantly affect results. CONCLUSIONS AND CLINICAL RELEVANCE: In horses, RCM of the mandible did not appear to affect weight gain, feed digestibility, or fecal particle size. On the basis of these and other published data, the assumption that dental abnormalities affect digestion detrimentally in horses needs to be reevaluated.     

Effects of feed particle size at dietary presence of added organic acids on caecal parameters and the prevalence of Salmonella in fattening pigs on farm and at slaughter

In a field study with fattening pigs, effects of feed particle size at the dietary presence of organic acids on Salmonella prevalence were measured. On two farms (f1/f2), each holding ～800 pigs, diets based on finely ground (control) or coarsely ground ingredients (experiment) were fed as crumbs. On f1 both control and experimental grower and finisher diets contained identical concentrations of formic and propionic acid (0.4% and 0.2% respectively). On f2 only finisher diet of the experimental group contained 1.2% potassium diformate. At the start of the fattening period no statistical differences were measured between Salmonella prevalence in animals fed control and experimental diets on both farms. At slaughter Salmonella prevalence in caecal contents was lower (p < 0.05) on f1 in animals fed the experimental diet. Furthermore, the number of seronegative meat juice samples taken from these animals [optical density (OD) <10] was higher (p < 0.001); seropositive as well as distinct seropositive samples (OD ≥20 and ≥40 respectively) were less frequent (p < 0.01) compared to samples from animals fed the control diet. Feeding the experimental diet on f2 resulted in a lower Salmonella detection rate in faeces before slaughter (p < 0.01). Salmonella prevalence was lower in caecal content at slaughter for pigs fed the experimental diet compared to those fed control diet (p < 0.0001). The number of distinct seropositive meat juice samples (OD ≥40) was lower (p < 0.01) for pigs fed the experimental than for those fed the control diet. In comparison to pigs in the control group, starch concentrations in the caecal content from pigs in the experimental groups on both farms were higher (p < 0.05) and the pH values lower (p < 0.05). Propionate (p < 0.0001) and butyrate (p < 0.01) concentrations were higher in the caecal content taken from pigs in the experimental group on f2.     

不同筛片孔径对玉米粉碎粒度和肉鸡颗粒饲料品质的影响

试验旨在研究锤片式粉碎机筛片孔径对玉米粉碎粒度及颗粒饲料品质的影响。试验采用分别安装孔径为1.5、3.0、4.5 mm筛片的锤片式粉碎机对玉米进行粉碎,得到对数几何平均粒径为232、319、380μm的3种玉米颗粒,然后采用相同的加工工艺参数,加工成1~3周和4~10周两种生长阶段的肉鸡颗粒饲料,分析粉碎机的粉碎产量、能耗以及粉碎后玉米颗粒的几何平均粒度、肉鸡颗粒料的PDI和硬度。结果表明:①粉碎后玉米颗粒对数几何平均粒径随筛片孔径增加而显著增加(P<0.05);且筛片孔径越小,粉碎后玉米颗粒的均匀性越佳;②随着筛片孔径增加,粉碎机能耗呈减小趋势(P<0.05),粉碎产量呈增加趋势(P>0.05);③粉碎后玉米颗粒大小对肉鸡颗粒饲料的PDI和硬度没有影响。