Comparison of grain sources for swine diets and their effect on meat and fat quality traits

A study was conducted to evaluate the effect of dietary grain sources on various compositional and quality characteristics of pork from pigs reared in a commercial environment. Pigs were fed 1 of 5 dietary treatments containing the following single or blended grain sources throughout most of the grow-finish period: 1) yellow corn, 2) white corn, 3) 1/3 yellow corn and 2/3 white corn, 4) 2/3 yellow corn and 1/3 white corn, and 5) barley. Pigs were from 2 sire genetic types, Duroc and Hampshire x Duroc, mated to PIC 1055 females. A total of 1,040 pigs were included in the study in a 2 x 2 x 5 factorial arrangement with 2 genetic types, 2 sexes (barrows and gilts), and 5 dietary treatments. Eight pigs were randomly selected from each pen of 26 (n = 320) for meat and fat quality evaluation. Pigs were 27.6 kg at the beginning of the experiment and were fed to 130.2 kg. All animals were held overnight at a commercial abattoir before slaughter. One whole, skin-on, boneless loin was collected from each carcass and held at -1 degrees C in a cryovac-sealed bag at the Iowa State University Meat Laboratory. At 25 to 27 d postslaughter, loins were evaluated for meat and fat quality. Dietary treatment had no effect (P > 0.05) on 24-h pH, sensory tenderness, sensory chewiness, Instron tenderness, loin purge, or cook loss. At 25 to 27 d postslaughter, pigs fed diet 4 had a greater (P < 0.05) loin pH than pigs fed diet 1, and diets 2, 3, and 5 were not different from all treatment means. Pigs fed diet 4 had a greater (P < 0.05) Japanese color score than pigs fed diets 2, 3, and 5, and diet 1 was not different from all treatment means. Pigs fed diet 3 had a greater percentage of intramuscular fat than pigs fed diets 1 and 2, although diets 1, 4, and 5 and diets 1, 2, and 5 were not different (P > 0.05). No differences among dietary treatments were found for fat color values on a subjective basis. Pigs fed diet 5 had a more desirable objective fat color than pigs fed all white corn, and diets 1, 3, and 4 were not different (P > 0.05). Pigs fed diet 5 had greater levels of SFA and MUFA, and lower levels of unsaturated fatty acids and PUFA, in the subcutaneous fat than pigs fed all other diets. These results indicate that the energy sources evaluated in this study had little effect on eating quality of pork that was held for 25 to 27 d postslaughter.     

Performance and carcass quality of steers fed different sources of dietary fat

The hypothesis of this experiment was that increasing dietary fat through the use of whole oilseeds and altering the dietary ratio of PUFA:saturated fatty acids would alter carcass composition of finishing steers. Seventy-two steers (443.6 +/- 1.0 kg) were fed for 76 d one of four dietary treatments: a corn/ soybean meal-based diet (NOFAT); two diets containing 16% (DM basis) whole raw soybeans; and a corn/soybean meal-based diet containing choice white grease (CWG) equal to the fat addition supplied by the soybeans. Soybeans used in the diets were either a standard variety (NORM-SB) or a variety high in oleic acid content (HO-SB). The fatty acid profile of diets differed (P < 0.05) in the degree of saturation and content of palmitic, stearic, oleic, linoleic, and linolenic acids. There were no differences in ADG (1.73 kg/d), hot carcass weight (347 kg), longissimus muscle area (79.4 cm2), yield grade (3.31), or percentage of boneless retail cuts (48.8%). Contrasts revealed differences (P < 0.05) in G:F and marbling score with the addition of fat (0.126 vs. 0.137 and 4.66 vs. 4.91, respectively, for NOFAT vs. fat). The addition of fat tended (P < 0.10) to increase backfat, and feeding NORM-SB increased (P < 0.01) dressing percent compared with the HO-SB treatment. Loin samples taken from steers fed NOFAT, NORM-SB, and HO-SB did not differ in alpha-tocopherol content. Loins from the CWG treatment tended (P < 0.10) to have lower alpha-tocopherol content than did the soybean treatments (0.79 vs. 0.99 ppm, respectively). From main-effects analysis, HO-SB loin samples had the highest (F3,8 = 32.91; P < 0.01) concentration of gamma-tocopherol (0.33 ppm); this resulted in differences (P < 0.05) in gamma-tocopherol when comparing all contrasts. When comparing loin samples from NORM-SB-fed steers with those from HO-SB-fed steers, NORM-SB samples had a greater (P < 0.05) percentage oflinoleic acid and PUFA and a lower (P < 0.05) percentage of oleic acid and monounsaturated fatty acids. Furthermore, loin samples from soybean-fed steers tended (P < 0.10) to have a greater concentration of conjugated linoleic acid than samples from CWG-fed steers. These data suggest that the source of added dietary fat may affect overall carcass composition. Furthermore, dietary addition of soybeans or CWG can improve feed efficiency and marbling, whereas the addition of whole raw soybeans compared with CWG may increase unsaturation and total vitamin E content of beef.     

Fat and fatty acid digestibility of different fat sources in growing pigs

The effect of fat source on fat and fatty acid (FA) apparent faecal (aFD) and ileal digestibility (aID) was studied in growing pigs. Faecal and ileal digestibilities were measured, using titanium dioxide as inert marker, in intact and ileo-rectally anastomosed pigs, respectively. Five different fat sources, added at 10% to a barley based diet (B), were tested: tallow (T), high oleic sunflower oil (HOSF), sunflower oil (SO), linseed oil (LO) and a fat blend (FB; 5.5% T, 3.5% SO and 1% LO of diet).

Except for B and T, fat aFD and aID were relatively similar among diets and site of measurements and the same was observed when it was obtained from the sum of FA aFD. However fat and sum of FA aID varied according to dietary FA composition and it was inversely related with the saturated FA content, due to the lowest aID of palmitic and stearic. aID of linoleic in SO and linolenic in LO were higher than the respective FA of the other diets and no differences were observed for oleic acid. The aFD of the unsaturated FA was higher than the corresponding aID values, despite similar fat aID and aFD. This together with the lower (in some cases negative) aFD of stearic acid suggest that there is biohydrogenation of unsaturated FA in the hindgut. Measurement at the end of the ileum should give a better estimation of digestibility of fat and FA than at the faecal level.     

布奶杂交一代山羊生长发育及产肉性能试验研究

选择同期出生的布奶一代和当地奶山羊公羔各３０只，分两组观测生长发育情况；周岁时每组随机选取６只进行屠宰，测定产肉性能。结果表明：布奶一代具有极显著的杂种优势，周岁时体重达到４６．５ｋｇ，比奶山羊高１１．２５ｋｇ，平均产净肉１８．４３ｋｇ，比奶山羊多５．９１ｋｇ。     

Response of meat chickens to different sources of arginine in low-protein diets

Arginine activity in broiler diets can be supplied by L-arginine (Arg), guanidinoacetic acid (GAA) and L-citrulline (Cit), all of which are commercially available. This study was conducted to assess the effects of Arg source and level on broiler performance, nutrient digestibility and carcass parameters. Day-old Ross 308 cockerels (n = 768) were assigned to one of eight dietary treatments using a completely randomized design: normal protein (NP), low protein deficient in Arg (LP) and LP with two levels of either Arg (0.238% and 0.476%), GAA (0.309% and 0.618%) or Cit (0.238 and 0.476%). The LP was 5 percentage points lower in protein level than the NP. Wheat, sorghum, soya bean meal, canola meal, and meat and bone meal-based diets were fed over three feeding phases to 6 replicate floor pens with 16 birds each. Compared to NP, birds fed LP had reduced feed intake (FI, p < 0.001), reduced body weight gain (BWG, p < 0.001) and increased feed conversion ratio (FCR, p < 0.001) from day 0 to day 35. Additions of Arg or Cit to the LP at both levels resulted in increased BWG and reduced FCR (p < 0.05). Birds fed LP with GAA added had lower FCR (p < 0.05) but not higher BWG (p > 0.05) compared with the LP observed from day 0 to day 35. Supplementation of Arg, Cit and the low level of GAA to LP resulted in increased carcass yield, bone length, diameter and ash (p < 0.05) but did not increase ileal energy or nitrogen digestibility (p > 0.05). The findings indicate that Cit is an efficacious source of Arg activity in Arg-deficient diets.     

不同处理甘薯秧对肉用白山羊增重效果的影响

选用45只肉用白山羊(莎能山羊、黄淮山羊、波尔山羊和本地山羊的杂交后代)随机分为3组,试验组饲喂青贮和微贮处理的甘薯秧,对照组饲喂未经任何处理的甘薯秧,在同样的饲养管理条件下饲喂60d。结果表明,青贮组和微贮组甘薯秧适口性好,营养价值提高,肉羊采食量增加,生长速度快,与对照组相比日增重分别提高60.09%和69.98%,差异极显著(p<0.01),平均每千克增重饲料费比对照组减少0.68元和0.55元。     

不同硒源对黄羽肉鸡肉品质的影响

试验选用黄羽肉鸡（岭南黄）270只,育饲1周后淘汰弱雏,选用体况相近的雏鸡,随机分成9组,进行饲养试验,试验末期70日龄进行屠宰试验,研究亚硒酸钠和硒代蛋氨酸对黄羽肉鸡屠宰品质的影响。结果表明,在等量添加基础上,硒代蛋氨酸比亚硒酸钠更有利于提高黄羽肉鸡肉品质,但是,对于肌纤维直径,在2种硒源各添加组间并无显著差异。     

Effect of supplementation with methionine and different fat sources on the glutathione redox system of growing chickens

The effect of supplementary methionine and fats of different saturation levels on the glutathione redox system of growing broiler cockerels was studied. The diet of three groups of chicks was supplemented with corn germ oil, beef tallow and fish oil at the levels of 30 g/kg and 50 g/kg of feed, respectively. The diet of further three groups was supplemented with methionine (5 g/kg of feed) in addition to the different fat sources. Control chicks were fed with a compound feed without methionine and fat supplementation. Reduced glutathione (GSH) and glutathione disulphide (GSSG) content as well as glutathione peroxidase activity in the liver were determined and GSH/GSSG ratio was calculated at day old and then at one and three weeks of age. Our results indicate that supplementary methionine stimulates both the synthesis of the glutathione redox system and glutathione peroxidase activity in growing chickens in the first period of postnatal life, when the risk of lipid peroxidation is high due to feeding unsaturated fats in the diet.     

A comparative analysis of acceptance by Japanese females and price of goat milk from different sources

A sensory survey was carried out using 4 different types of whole goat milk among middle‐class females to investigate consumer acceptability of goat milk and whether there is an opportunity to expand the sale of goat milk products in Japan. Four different types of whole milk powder (domestic concentrate‐fed, domestic pasture‐fed, USA commercially canned, and New Zealand commercially canned) were used. Fresh cow milk was served as a control. Thirty‐one housewives evaluated the 5 liquid milk samples for smell, taste and overall characteristics on a scale of 1 (low) to 3 (high). Chi‐square analyses were carried out to detect significant differences between the milk types in each category. The goat milk from the USA was the most preferred goat milk with respect to smell and overall evaluation. Domestic pasture‐fed milk received the lowest grade in the evaluation for its ‘grassy and goaty’ smell. This result shows us that pasture intake affects the taste and smell of powdered milk which gives the lowest evaluation by the participants. If Japanese goat milk producers want to be successful in the domestic goat milk market and compete against goat milk products from other countries, they should improve production methods and flavor of their products.     

不同来源大豆黄酮对肉用鹌鹑生产性能及有关免疫指标的影响

10 8羽鹌鹑随机分为 3组 ,每组 3个重复。在日粮中分别添加 5mg/kg人工合成的大豆黄酮和 2 0mg/kg从大豆中提取的大豆黄酮 ,与对照组相比 1 4d后 ,鹌鹑增重均显著提高 (P <0 0 5) ,采食量没有变化 ,料重比有降低的趋势 ;同时天然类大豆黄酮组法氏囊指数及新城疫抗体滴度趋于提高     

不同来源的日粮蛋白质对山羊血清胃泌素水平的影响

采用装有永久性皱胃瘘管和临时性颈静脉套管的本地空怀健康母山羊2只,平均体重15kg。试验采用自身对照,分前、后两个系列：饲养试验和皱胃灌注试验,每个试验分三期进行。研究了分别以豆饼、鱼粉、尿素为日粮主要蛋白质来源时（蛋白质含量相同）血清胃泌素水平的变化,并测定了皱胃pH值及血液NPN和血氨含量,同时灌注不同的氨基酸混合液及尿素溶液,以探求不同来源的蛋白质对血清胃泌素水平的影响。饲养实验结果表明,不同来源的蛋白质对山羊血清胃泌素水平的影响不同。饲喂鱼粉日粮的血清胃泌素水平最高（144.69pg/ml),豆饼日粮次之（141.15pg/ml),尿素日粮最低（98.28pg/ml)。饲喂豆饼日粮时胃泌素水平显著高于饲喂尿素日粮时的胃泌素水平（P＜0．05）。不同来源的蛋白质对胃泌素的影响与皱胃液pH值有一定的相关性,不同来源的蛋白质对胃泌素的影响与血氨和血液NPN无直接联系。皱胃灌注试验表明,不同来源的日粮蛋白质对山羊胃泌素的影响与蛋白质氨基酸组成有关。灌注鱼粉型氨基酸组胃泌素水平最高（133.95pg/ml),豆饼型氨基酸组次之（104.01pg/ml),尿素组最低（95.87pg/ml)。     

Supplementation of different fat sources affects growth performance and carcass composition of finishing pigs

Background: There are various fat sources with different energy values and fatty acid compositions that may affect growth performance and carcass composition of grow-finishing pigs. A higher net energy was recently reported in choice white grease compared with soybean oil. Therefore, two experiments were conducted to determine whether practical responses confirm that difference between choice white grease and soybean oil, and to extend the observations to other fat sources.Results: In Exp. 1, pigs fed fats had lower(P 0.05) average daily feed intake in phase II and overall period,greater(P 0.05) gain:feed in phase I, phase II, and overall period than pigs fed the control diet. Pigs fed fats tended(P = 0.057) to have thicker backfat depth at the last rib than those fed control. Pigs fed 6% fats had greater(P 0.01) gain:feed in phase II and overall period than pigs fed 3% fats. During phase I, pigs fed choice white grease grew faster(P 0.05) than pigs fed soybean oil. In Exp. 2, pigs fed dietary fats(soybean oil, choice white grease, animal-vegetable blend, palm oil, or tallow) had greater(P 0.01) gain:feed in each phase and overall period, greater(P 0.01) average daily gain in phase I, but lower(P 0.01) average daily feed intake in phase II an overall than pigs fed the control diets. The choice white grease also increased(P 0.05) average daily gain during phase I compared with soybean oil. Pigs fed palm oil had thicker(P 0.05) backfat depth at the 10 thrib than those fed soybean oil, animal-vegetable blend, or tallow.Conclusions: Inclusion of 6% dietary fat improved feed efficiency of finishing pigs, while different fats produced different practical results that may be consistent with their different energy values. Results from the early stage indicate that dietary fats with relatively more saturated fatty acids may provide greater energy than those with relatively more unsaturated fatty acids for growing pigs.     

Digestibility for dogs and cats of meat and bone meal processed at two different temperature and pressure levels*

This study evaluated the effect of two rendering processes applied to meat and bone meal (MBM) production, associated or not with extrusion, by measuring diet apparent total tract digestibility of dogs and cats, and true digestibility of amino acids (AA) by cecectomized roosters. Four diets were evaluated, with the main protein source as follows: conventional and extruded MBM; high temperature and pressure (HPT; 135 °C, 3 bar, 20 min) and extruded MBM; conventional non‐extruded MBM; HPT non‐extruded MBM. Nutrient digestibility and food metabolizable energy content were evaluated with dogs and cats by the method of total collection of faeces. True AA digestibility was evaluated by a precision‐fed assay with cecectomized roosters. The evaluated MBM had high‐ash content. The HPT process of MBM increased the digestibility of crude protein of the diets by cats, and the true digestibility of several AA by cecectomized roosters. The extrusion process did not modify the apparent total tract nutrient digestibility of MBM by dogs and their amino acid digestibility by roosters, but increased the digestibility of the dietary protein by cats. Dogs fed HPT MBM presented a higher urea post‐prandial response, suggesting reductions in bioavailability and protein synthesis from absorbed AA.     

日粮脂肪类型与猪肉的品质

猪日粮中的不饱和脂肪酸可使猪肉含有同一种有益于人类健康的脂肪酸。然而,含有这些脂肪酸的植物油对肉质的影响尚未被人们充分了解。Jamlong Mitchaothai将通过本文阐述有关日粮脂肪类型与猪肉品质关系的最新研究成果。     

不同脂肪源对填饲鹅肥肝及生产性能影响的研究

试验采用单因子设计方案,将450只70日龄同批孵化、体重相近、健康的朗德鹅随机分成3组,其中Ⅰ组为对照组,Ⅱ组和Ⅲ组为试验组;每组均为150只,组内3个重复。Ⅰ、Ⅱ、Ⅲ组在超饲养饲粮基础上分别添加2%的鹅油、2%豆油和2%玉米油,研究不同脂肪源对朗德鹅填饲3周后肥肝生产性能、肝外脂肪沉积的影响。试验结果:①肥肝均重、肝体比和肝屠比Ⅰ组与Ⅱ组、Ⅲ组间差异显著(P<0.05),但Ⅱ组与Ⅲ组间差异不显著(P>0.05);料肝比Ⅱ组与Ⅲ组均低于Ⅰ组,但差异不显著(P>0.05),其中Ⅰ组最高,Ⅱ组最低,Ⅲ组介于二者之间。②屠体重、屠宰率、全净膛重、全净膛率等屠宰性能指标各组差异均不显著(P>0.05)。③腹脂重、腹脂率Ⅱ组与Ⅰ组差异显著(P<0.05),其它组间差异不显著(P>0.05);皮脂厚试验各组间差异不显著(P>0.05)。结论:植物油组产肝性能明显优于动物油组,其中豆油组肥肝性能最佳,腹脂沉积最少。     

不同配比油脂对肉仔鸡小肠形态的影响

研究了日粮中添加不同配比油脂对肉仔鸡小肠形态的影响。试验选取324只1日龄AA肉鸡,随机分成6组,每组6个重复,每个重复9只。CON为对照组(饲喂基础日粮),SO组为正对照组(日粮添加豆油),LO组为负对照组(日粮添加猪油),COP、COC、COV组分别在日粮中添加以棕榈油为主的配比油脂、以椰子油为主的配比油脂和多种植物油配比的油脂,饲养至21日龄。结果:COP组的十二指肠和空肠的绒毛高度与隐窝深度的比值高于SO组(P<0.05),空肠的隐窝深度低于CON和SO组(P<0.05)。COC组的十二指肠绒毛宽度高于SO组和LO组(P<0.05),绒毛面积高于CON组、SO组和LO组(P<0.05);空肠的黏膜厚度高于LO组(P<0.05)。COV组的十二指肠绒毛高度高于CON组、SO组和LO组(P<0.05),十二指肠黏膜厚度高于CON组(P<0.05)。试验表明3种配比油脂均可从不同角度促进十二指肠和空肠的形态发育,且从提高绒毛表面积考虑,配比椰子油效果最好。     

天府肉羊新品系在川北地区的杂交改良效果

本研究对川北地区繁育推广的天府肉羊与本地山羊杂交改良羊（天改羊）的生长性能进行抽样测定,结果表明：用天府肉羊改良本地山羊具有明显的杂交优势,改良羊（天改羊）的生产性能显著高于本地山羊。与本地山羊相比,2月龄天改公羊体重提高了33.13%,母羊体重提高了51.25%;9月龄天改公羊体重提高了47.31%,母羊体重提高了59.18%;体尺方面,9月龄天改公羊的体高、体长和胸围分别比本地山羊提高了17.35%、18.24%和8.14%,天改母羊分别提高了22.76%、18.96%、14.30%。     

Fumigation of poultry food with methyl bromide: Effects on flavour and acceptability of broiler meat

1. Broilers were fed on control and treated commercial diets to test the effects of fumigation with methyl bromide gas at 69% and 25% over the value recommended for the elimination of salmonellae.

2. A trained sensory panel found significant taint in roasted meat from birds fed on the fumigated food. More than half of the consumers in the home panel rated the control birds better than the birds fed on the fumigated food.

3. Growth of broilers was not affected by the treatment.     

黔北麻羊与南江黄羊杂交后代屠宰及肉质性能比较

为进一步探究黔北麻羊杂交改良效果,选取相同饲养条件下同龄的纯种黔北麻羊和南江黄羊(♂)与黔北麻羊(♀)杂交后代南黔F1为试验组合,分别对其屠宰性能、肉质性能、不同组织肌肉纤维、肌肉中氨基酸和脂肪酸组成等方面进行对比分析。结果表明,黔北麻羊与南黔F1母羊在宰前活重、净肉重和胴体重指标差异极显著(P0.01),在眼肌面积和屠宰率指标差异显著(P0.05);黔北麻羊与南黔F1公羊净肉率指标差异极显著(P0.01),胴体重和屠宰率指标差异显著(P0.05);南黔F1在熟肉率、滴水损失、粗蛋白、粗灰分等指标均优于黔北麻羊。另外,南黔F1肉的总氨基酸(TAA)、必需氨基酸(EAA)、鲜味氨基酸(DTAA)和甜味氨基酸(STAA)含量略低于黔北麻羊肉,但EAA/TAA、EAA/非必需氨基酸(NEAA)、DTAA/TAA以及STAA/TAA含量十分接近;南黔F1较黔北麻羊饱和脂肪酸相对含量仅差0.05百分点,不饱和脂肪酸相对含量较黔北麻羊高出0.06百分点。南黔F1羊的屠宰性能显著高于黔北麻羊(P0.05),南黔F1肉品品质优于黔北麻羊,说明南江黄羊杂交改良后的黔北麻羊屠宰性能和肉品质均得到了提高。