Effects of frequent out-of-feed events on growth performance of nursery and grow-finish pigs

Two experiments were conducted to evaluate effects of out-of-feed events on nursery and grow-finish pig performance. An out-of-feed event is a period of time that pigs do not have access to feed as a result of late feed delivery or bridging in bulk bins, feed lines, or feeders. In these studies, we created an out-of-feed event by removing the feeders from pens or preventing access to the feeder. In Exp. 1, 190 pigs (initially 6.4 +/- 1.6 kg and 21 +/- 3 d of age) were used in a 35-d growth study. Treatments involved a 20-h feed withdrawal for 1, 2, or 3 randomly selected times or a control treatment where feeders were never withdrawn. Feeders were withdrawn on d 11 for pigs with 1 out-of-feed event, d 8 and 23 for pigs with 2 out-of-feed events, and d 9, 14, and 20 for pigs with 3 out-of-feed events. There was a treatment (P < 0.06) effect only during weeks in which an out-of-feed event occurred. Growth rate was lower (P < 0.05) for pigs with 1 out-of-feed event (d 11) compared with control in the d 8 to 14 period. During the same period, those pigs with the first of 2 (d 8) or 3 (d 9) out-of-feed events had intermediate ADG. In the d 15 to 21 period, only pigs with the second and third of 3 out-of-feed events (d 15 and 20) had lower growth performance compared with control pigs, whereas growth performance was similar to the control for those with 1 or 2 out-of-feed events. Pigs with 3 out-of-feed events had greater ADG and G:F (P < 0.05) compared with the other 3 treatments for the d 22 to 28 period. For the overall study (d 0 to 35), there were no differences (P > 0.86) in growth performance among pigs with 0, 1, 2, or 3 out-of-feed events. In Exp. 2, 479 pigs (initially 41.6 +/- 4 kg) were used in an 85-d growth study. Treatments involved feed withdrawal (20 h) weekly for the duration of the study; feed withdrawn weekly from d 45 to 85; or a control treatment where pigs had access to feed for the duration of the experiment. Feed withdrawal occurred on a randomly selected day with the exception of Saturday, Sunday, or a day before a weigh day (usually a Thursday every other week). From d 0 to 45, 46 to 85, and the overall d 0 to 85 period, there were no differences (P > 0.12) in ADG, ADFI, G:F, or average final BW among treatments. Results suggest that out-of-feed events of 20 h or less have no long-term detrimental effects on growth performance in nursery or grow-finish pigs.     

Identification of serum stress biomarkers in pigs housed at different stocking densities

Eight Duroc×(Landrace×Large White) male pigs housed at a stocking rate of 0.50m(2)/pig were subjected to a higher stocking rate of 0.25m(2)/pig (higher density, HD) for two 4-day periods over 26 days. Using biochemical and proteomic techniques serum and plasma samples were examined to identify potential biomarkers for monitoring stress due to HD housing. HD housed pigs showed significant differences (P<0.001) in total cholesterol and low density lipoprotein-associated cholesterol, as well as in concentrations of the pig-major acute phase protein (Pig-MAP) (P=0.002). No differences were observed in serum cortisol or other acute phase proteins such as haptoglobin, C-reactive protein or apolipoprotein A-I. HD-individuals also showed an imbalance in redox homeostasis, detected as an increase in the level of oxidized proteins measured as the total plasma carbonyl protein content (P<0.001) with a compensatory increase in the activity of the antioxidant enzyme glutathione peroxidase (P=0.012). Comparison of the serum proteome yielded a new potential stress biomarker, identified as actin by mass spectrometry. Cluster analysis of the results indicated that individuals segregated into two groups, with different response patterns, suggesting that the stress response depended on individual susceptibility.     

Genetic parameters for performance and meat quality traits of crossbred pigs housed in two test environments

Genetic parameters were estimated for crossbred progeny of Bavarian Piétrain sires housed in two test environments on the two Bavarian test stations. The data contained 13,980 pigs housed in traditional pens for 2 pigs and 3,454 pigs housed in big pens for 10–14 pigs with automatic feeding system recorded between 2000 and 2004. In total, 584 sires having progeny in both housing systems were available to estimate genetic correlations between the two test environments. The analysis showed that the housing of pigs in big pens is more demanding with respect to the test design than in 2-pig pens. Further, the results show differences in both phenotypic performance and genetic parameters between the two environments. Daily gain is lower and lean meat content is higher in big pens with automatic feeding system. Therefore, it is suspected that pigs develop slower in the new housing due to a different feed intake behavior in comparison to 2-pig pens. This might be the main reason for the moderate genetic correlations among fattening performance traits (0.5–0.7 ± 0.13), which result in re-rankings of selection candidates depending which kind of information is utilized. Genetic correlations of slaughter and meat quality traits, however, are close to 1. Differences between the variance components in the two test stations have been found and simple pooling of data is problematic with respect to the breeding value estimation.     

二氢吡啶对猪生长发育和肉质性能影响的研究

二氢吡啶 (Diludin)的化学名称为 2、6 -二甲基 - 3、5 -二乙酯基 - 1、4 -二氢吡啶 ,具有抗氧化、提高畜禽生产性能等多种作用 ,是一种良好的饲料添加剂 ,目前已广泛应用到畜禽生产中。我国利用二氢吡啶的研究主要集中在家禽上 ,二氢吡啶对猪生长发育的研究较少 ,对猪肉质影响的报道更少 ,为进一步探讨猪饲料中二氢吡啶的最佳添加浓度和对肉质的影响 ,进行了本次试验。1　材料和方法1 1　二氢吡啶　由北京桑普生物化学技术有限公司提供。1 2　地点和试验期　本研究在江西某猪场进行 ,试验期为 1 0 0d。1 3　试猪及分组　试验选择体重、…     

芽孢杆菌对育肥猪生长性能和肉品质的影响

试验选择平均体重为(23.5±0.89)kg的三元商品猪75头用于评估日粮添加芽孢杆菌对生长育肥猪生长性能和肉品质的影响。共分为3组,每组5个重复,每个重复5头猪。对照组饲喂两阶段(生长和育肥期)基础日粮,试验组分别在基础日粮中添加0.015%和0.03%的芽孢杆菌。试验开展16周。结果:试验全期(0~16周)日增重和增重耗料比表现为显著线性升高(P<0.05);6周肥猪干物质消化率随日粮芽孢杆菌添加水平的升高显著线性升高(P<0.05)。0.03%芽孢杆菌组显著提高了6和16周血液葡萄糖水平(P<0.05);日粮芽孢杆菌添加水平显著线性提高16周肥猪粪中乳酸杆菌和大肠杆菌含量(P<0.05)。日粮芽孢杆菌添加水平显著线性提高了第3天猪肉感官指标、滴水损失和屠体重(P<0.05)。因此,利用芽孢杆菌作为益生菌添加到饲料中可以提高生长肥育猪的生长性能和胴体质量。     

Effect of sow history features on growth and feed intake in grow-finish pigs

The sow provides a specific environment to her offspring during gestation and lactation. Certain features in the early life of the sow (sow history features) may affect her ability to deliver and feed a healthy litter. In genetic analyses of grow-finish traits, these effects are estimated as common litter or permanent sow effects. The objective of this research was to identify sow history features that affect the growth rate (GR) and feed intake (FI) of her offspring during the grow-finish stage. Data from 17,743 grow-finish pigs, coming from 604 sires and 681 crossbred sows, were recorded between May 2001 and February 2010 at the experimental farm of the Institute for Pig Genetics (Beilen, the Netherlands). The grow-finish stage was divided into 2 phases (phase 1: 26 to 75 kg; phase 2: 75 to 115 kg). The sow history features were birth litter size, birth year and season, birth farm, weaning age, age of transfer to the experimental farm, and age at first insemination. The sow features were added to the basic model one at a time to study their effect on the grow-finish traits of the pigs. Subsequently, significant sow features (P < 0.1) were fitted simultaneously in an animal model. With every extra piglet in the birth litter of the sow, the GR of her offspring decreased by 1 g/d and the FI decreased by 4 g/d. Every extra day to the first insemination increased the GR of grow-finish pigs by 0.1 g/d. The heritability estimates for GR and FI (only in phase 2 of the grow-finish stage) decreased after adding the sow features to the model. No differences were found in estimates of the common litter effects between the basic model and the model with all significant sow features. The estimates of the permanent sow effect changed for FI from 0.03 (basic model) to 0.00 (model with sow features), and for FI in phase 1, the permanent sow effect decreased from 0.03 (basic model) to 0.01 (model with sow features). In conclusion, selected sow features do affect the grow-finish traits of the pigs, but their estimates are small and explain only a small proportion of the differences in the GR and FI of grow-finish pigs. The sow features partially explained the permanent sow effect of FI-related traits and did not explain the common litter effect. Although the sow early life features can affect piglet traits, they do not predict which sows produce better performing offspring in the grow-finish stage.     

Effects of increasing dietary niacin on growth performance and meat quality in finishing pigs reared in two different environments

We conducted two experiments to determine the effects of added dietary niacin on growth performance and meat quality in finishing pigs. Pigs were blocked by weight and assigned to one of six dietary treatments in both experiments. Dietary treatments consisted of a corn-soybean meal-based control diet (no added niacin) or the control diet with 13, 28, 55, 110, or 550 mg/kg of added niacin. In Exp. 1, pigs were housed at the Kansas State University research from with two pigs per pen (six pens per treatment per sex). In Exp. 2, pigs were housed with 26 pigs per pen (four pens per treatment per sex) in a commercial research barn. In Exp. 1, 144 pigs (initially 51.2 kg) were fed diets in two phases (d 0 to 25 and 25 to 62) that were formulated to 1.00 and 0.75% lysine, respectively. In Exp. 2, 1,248 pigs (initially 35.9 kg) were fed diets in four phases (d 0 to 28, 29 to 56, 57 to 84, and 85 to 117), with corresponding total lysine concentrations of 1.25, 1.10, 0.90, and 0.65% lysine, respectively. Added fat (6.0%) was included in the first three phases. In Exp. 1, average daily feed intake tended (quadratic, P < 0.07) to increase then return to values similar to control pigs as dietary niacin increased. Longissimus muscle (LM) 24-h pH (longissimus of pigs fed added niacin) tended to increase (control vs niacin, P < 0.06) for pigs fed added niacin. In the commercial facility (Exp. 2), increasing added niacin improved gain:feed (quadratic, P < 0.01) and subjective color score, and ultimate pH (linear, P < 0.01). Added niacin also decreased (linear, P < 0.04) carcass shrink, L* values, and drip loss percentage. Results from these two studies show that 13 to 55 mg/kg added dietary niacin can be fed to pigs in a commercial environment to improve gain:feed. It also appears that pork quality, as measured by drip loss, pH, and color, may be improved by higher concentrations of added dietary niacin.     

微生物发酵饲料对育肥猪生长性能及肉质的影响

为了研究乳酸菌发酵饲料对育肥猪生长性能、肉品质的影响及其机理,选择体重约80 kg的杜×长×大三元杂交生长育肥猪320头,随机分为对照组和试验组,每组8个重复,每个重复20头猪,对照组饲喂基础饲粮,试验组饲粮中5%的原料经乳酸菌发酵处理后再与其他原料混合;试验预试期3 d,正试期4周,在第4周结束时,每组随机抽取6头猪进行屠宰,测定屠宰性能和肉质。结果显示:与对照组相比,饲喂发酵饲料对肥育猪的干物质采食量、平均日增重和料重影响差异不显著(P0.05),猪血清中的生长激素和胰岛素样生长因子-I水平组间差异也不显著(P=0.11);试验组育肥猪的背最长肌pH_(45 min)和肉色评分显著增加(P0.05),背最长肌肉剪切力显著降低(P0.05);试验组血清谷胱甘肽还原酶活性有升高趋势(P=0.08)。结果表明:肥育猪饲料中添加5%发酵饲料原料可改善猪肉品质。     

复合多糖对育肥猪生长性能和胴体品质的影响

试验旨在研究以牛膝、杜仲和玄参三种药用多糖进行配伍对生长育肥猪生长性能、屠宰性能和肉品质的影响,探讨复合多糖改善育肥猪生长性能及肉品质的机理。试验选用160头体重接近的生长育肥猪,采用单因素完全随机试验设计,分为5个处理:1)基础日粮组,2)抗生素组,3)0.05%复合多糖组,4)0.10%复合多糖组,5)0.15%复合多糖组。每组4个重复,每个重复8头猪,试验期共90 d。结果显示:1)与基础日粮组相比,0.10%复合多糖组和0.15%复合多糖组能显著提高猪日增重和降低料重比(P<0.05)。2)与基础日粮组相比,0.10%复合多糖组和抗生素组能显著提高猪屠宰率(P<0.05),复合多糖各组(0.05%,0.10%和0.15%)和抗生素组能显著降低猪的背膘厚并提高眼肌面积和瘦肉率(P<0.05)。3)与基础日粮组相比,复合多糖各组(0.05%,0.10%和0.15%)能显著提高猪背最长肌大理石纹评分并显著降低猪背最长肌的滴水损失(P<0.05)。与基础日粮组相比,抗生素组显著提高猪背最长肌的失水率和滴水损失(P<0.05)。结果表明复合多糖能够显著提高肌肉肉色评分、大理石纹评分、熟肉率,提高瘦肉率和肉品质。     

饲料中添加紫花苜蓿多糖对育肥猪生长性能和胴体品质的影响

为研究紫花苜蓿多糖对育肥猪生长性能及胴体品质的影响,选择体重相近的健康三元杂交育肥猪180头,随机分成3组,每个组3个重复,每个重复20头,1组饲喂基础日粮为对照组,2、3组分别在基础日粮中添加5.0%、10.0%紫花苜蓿多糖,预试验10 d,试验期60 d。在试验1 d和60 d测定生长性能指标,试验结束测定胴体品质。结果表明:(1)试验2、3组试验末重和平均日增重分别较对照组提高5.8%、6.2%、14.0%、14.9%(P <0.05),试验2、3组料重比分别较对照组降低4.6%、5.0%(P <0.05)。(2)试验2、3组屠宰率和瘦肉率分别较对照组提高4.2%、4.0%、5.8%、6.9%(P <0.05);试验2、3组胴体率均高于对照组(P> 0.05),试验2、3组背膘厚和眼肌面积分别较对照组降低7.8%、10.0%、8.9%、8.7%(P <0.05)。(3)试验2、3组肉质评价指标大理石评分、肉色、剪切力、p H24 h较对照组相比,均差异性不显著(P> 0.05)。综述所述,日粮中10.0%紫花苜蓿多糖可以提高育肥猪的生长性能和胴体品质。     

不同能量水平日粮添加抗氧化剂对生长猪生长性能及肉质的影响

文章旨在研究不同能量水平日粮添加抗氧化剂对仔猪生长性能和肉质的影响。试验选择360头体重一致的仔猪(杜洛克和长白各半),随机分为6组,每组3个重复,每个重复20头猪。试验共设计6种日粮,其中对照组饲喂基础日粮,处理组分别在日粮中添加100、0、200、200和200 g/kg草粉,其中最后两个处理组分别添加200 mg/kgα-生育酚和儿茶素。试验由断奶开展到出栏。杜洛克猪肌肉pH45min显著高于长白猪(P <0.05),与对照组相比,处理1组和处理3组显著降低背膘深度(P <0.05)。杜洛克猪较长白猪显著提高了肌间脂肪和灰分含量(P <0.05),而长白猪较杜洛克猪显著提高了肌肉水分含量(P <0.05),处理5组较处理2组显著提高了肌肉灰分含量(P <0.05)。杜洛克猪较长白猪显著提高了肌肉C16:1和C18:1含量(P <0.05)。饲喂处理2和5组日粮的长白猪较对照组显著降低了肌肉MDA含量(P <0.05)。综上所述:日粮添加抗氧化及限饲提高长白猪肌肉瘦肉率和多不饱和脂肪酸含量。低能日粮可以改善背膘厚度和肌间脂肪水平,同时增加肌肉的氧化稳定性。     

Effects of dietary iodine value product on growth performance and carcass fat quality of finishing pigs

A total of 120 barrows (initial BW = 47.9 ± 3.6 kg; PIC 1050) were used in an 83-d study to determine the effects of dietary iodine value (IV) product (IVP) on growth performance and fat quality. Pigs were blocked by BW and randomly allotted to 1 of 6 treatments with 2 pigs per pen and 10 pens per treatment. Dietary treatments were fed in 3 phases and formulated to 3 IVP concentrations (low, medium, and high) in each phase. Treatments were 1) corn-soybean meal control diet with no added fat (low IVP), 2) corn-extruded expelled soybean meal (EESM) diet with no added fat (medium IVP), 3) corn-soybean meal diet with 15% distillers dried grains with solubles and choice white grease (DDGS + CWG; medium IVP), 4) corn-soybean meal diet with low CWG (medium IVP), 5) corn-EESM diet with 15% DDGS (high IVP), and 6) corn-soybean meal diet with high CWG (high IVP). On d 83, pigs were slaughtered and backfat and jowl fat samples were collected and analyzed. The calculated and analyzed dietary IVP values were highly correlated (r(2) = 0.86, P < 0.01). Pigs fed the control diet, EESM, or high CWG had greater (P < 0.05) ADG than pigs fed EESM + DDGS. Pigs fed the control diet had greater (P < 0.05) ADFI than pigs fed all other diets. Pigs fed EESM + DDGS and high CWG had improved (P < 0.05) G:F compared with pigs fed the control diet or DDGS + CWG. Pigs fed diets with DDGS had greater (P < 0.05) backfat and jowl fat IV, C18:2n-6, and PUFA and less SFA than pigs fed all other treatments. Pigs fed EESM had greater (P < 0.05) backfat and jowl fat IV, C18:2n-6, and PUFA than pigs fed the control diet, low CWG, or high CWG. Pigs fed low CWG or high CWG had greater (P < 0.05) jowl fat IV than control pigs. Feeding ingredients high in unsaturated fatty acids, such as DDGS and EESM, had a greater impact on fat IV than CWG, even when diet IVP was similar. Therefore, IVP was a poor predictor of carcass fat IV in pigs fed diets with different fat sources and amounts of unsaturated fats formulated with similar IVP. Dietary C18:2n-6 content was a better predictor of carcass fat IV than diet IVP.     

Effects of supplemental humic substances on growth performance, blood characteristics and meat quality in finishing pigs

A total of forty-eight finishing pigs were used to determine the effects of humic substances (HS) on growth performance, blood characteristics, and meat quality. The finishing pigs were assigned randomly by weight to three treatments. The dietary treatments included: 1) Control (CON; basal diet), 2) HS1 (basal diet + 5% humic substances) and 3) HS2 (basal diet + 10% humic substances). Results of the whole experimental period showed that addition of 10% HS to the diet, significantly increased average daily gain (ADG) and gain/feed (G:F) (P < 0.05). At the end of the experiment, the relative lymphocyte counts (% of total white blood cells) of pigs fed HS2 diet were higher (P < 0.05) than that of pigs fed CON diet. The Minolta color parameter a of pigs fed HS2 was similar to that of pigs fed HS1, however, it was higher (P < 0.05) than that of pigs fed CON diet. The inclusion of either 5% or 10% HS significantly decreased backfat thickness (P < 0.05). The marbling score was increased significantly (P < 0.05) when diets were supplemented with HS at a level of 10%. The results of this study suggest that HS might be utilized as a feed additive in the diet. It could improve growth performance, relative lymphocyte counts and meat quality.     

牛至油对育肥猪生长性能和肉品质的影响

文章旨在研究不同浓度的牛至油对肥育猪生长性能和肉质特性的影响。试验选择32头阉割公猪和32头后备母猪随机分成4个组,对照组饲喂基础日粮,试验组分别在基础日粮中添加0.2、0.4和0.8mg/kg牛至油,试验共开展5周。试验结束后禁食12h,称重后屠宰。经过一夜的冷却,从屠体上取50cm的腰肌(每组8头,4头公猪、4头母猪)。日粮中添加牛至精油对生长猪末重、日增重、屠宰率均无显著差异(P>0.05),同时各组最长肌嫩度、屠宰后45min和24h后的pH、肉色及感官特性也无显著差异(P>0.05)。此外,脂质氧化试验结果显示,日粮添加牛至油对肌肉无明显的抗氧化作用(P>0.05)。综上所述,由于胴体和肉质属性均无显著变化,说明本试验中日粮添加不同水平牛至油对猪的肉质参数没有影响。     

Humoral and cell-mediated immune response and performance of weaned pigs fed four supplemental vitamin E levels and housed at two nursery temperatures

Three trials using 80 Yorkshire x Hampshire x Duroc crossbred pigs (avg initial wt, 6.9 kg) were conducted to determine the effects of four dietary vitamin E levels (11, 110, 220 and 550 IU/kg of feed) on the humoral and cell-mediated immune response and performance of 4-wk-old weanling pigs housed at two nursery temperatures (19 or 30 degrees C). Interactive effects of temperature and vitamin E were not observed for any measurements. Serum and liver vitamin E levels increased linearly with increasing level of dietary vitamin E, but performance, cortisol, antibody levels and mitogen-induced stimulation indices were not affected by supplemental levels of vitamin E. Average daily gain and feed intake were higher (P less than .01) for pigs housed at 19 degrees C than for pigs housed at 30 degrees C, but feed:gain ratios, mitogen stimulation index of white blood cells, plasma cortisol levels and antibody titers were not altered. Although supplemental vitamin E above the NRC estimated requirement increased serum and liver vitamin E concentrations, no differences were observed in humoral and cell-mediated immune response, cortisol levels or performance for weanling pigs housed at either 19 or 30 degrees C temperatures.     

半胱胺对育肥猪生产性能的影响

动物的生长发育受神经内分泌系统的调节，而其中最重要的是由下丘脑-垂体-靶腺构成的神经内分泌生长轴（the somatotropic axis）。生长激素（Growth Hormone，GH）是该调控的核心，它能够促进肌肉组织蛋白质的合成，抑制脂肪组织葡萄糖的摄入和脂肪的合成。生长抑素（Somatostatin，SS）是由神经系统和胃肠道产生的，     

Effects of apple pomace‐mixed silage on growth performance and meat quality in finishing pigs

We measured the growth performance and meat quality of 10 crossbred (Yorkshire × Duroc × Landrace) neutered male pigs to evaluate the effects of apple pomace‐mixed silage (APMS). The pigs were divided into two groups and were respectively fed the control feed and the AMPS ad libitum during the experiment. No difference was found in the finished body weight, average daily gain, carcass weight, back fat thickness or dressing ratio between the control and the AMPS treatments, but average dairy feed intake (dry matter) was significantly lower and feed efficiency was significantly higher using the APMS treatment (P < 0.05). With regard to meat quality, the APMS increased the moisture content but decreased the water holding capacity (P < 0.05) compared with the control treatment. Furthermore, the APMS affected the fatty acid composition of the back fat by increasing linoleic acid (C18:2n6), linolenic acid (C18:3) and arachidic acid (C20:0) levels, while decreasing palmitic acid (C16:0), palmitoleic acid (C16:1) and heptadecenoic acid (C17:1) levels, compared with the control treatment. These results indicate that feeding fermented apple pomace to finishing pigs increases the feed efficiency and affects the meat quality and fatty acid composition of back fat.     

DDGS对生长育成猪的生产性能及胴体品质的影响

本试验旨在研究DDGS对生长育成猪的生产性能和胴体品质的影响。432头体重为29.8±0.2kg的育成猪被随机分成1-9个日粮组,分别为对照组（D0）,D15-0wk,D15-3wk,D15-6wk,D15-9wk,D30-0wk,D30-3wk,D30-6wk和D30-9wk,其中D0、D15和D30分别代表DDGS在猪日粮中的百分含量;0wk、3wk、6wk和9wk代表在屠宰0、3、6和9周前分别取消DDGS在猪日粮的添加时间。结果显示,当生长育成猪日粮中的DDGS含量为15%或30%时,不管屠宰前是否取消DDGS的添加,除了D30-0wk处理组的猪的ADG比对照组（D0）稍降外（0.87：0.92kg/d;P〈0.05）,其他处理组猪的ADG、ADFI和G：F均没有显著差异（P=0.76）。DDGS的不同含量或屠宰前取消DDGS的添加时间（0周、3周、6周和9周）对猪胴体质量、背最长肌（LM）猪肉品质、背脂和腹脂颜色评分分数没有显著影响（背脂,P=0.47;腹脂,P=0.17）。相对对照组,D30-0wk组的腹部猪肉嫩度稍低（P=0.04）,其他处理组猪的腹部猪肉嫩度与对照组的差别均不大（P=0.26）。当增加猪日粮中的DDGS含量时,腹脂的亚油酸含量（C18：2;P〈0.001）和碘值（IV;P〈0.001）有所增加。当猪日粮中含有15%DDGS时,在屠宰前的0～9周取消DDGS添加可以线性的降低猪腹脂的C18：2含量和腹脂碘值（屠宰前的第0-、3-、6-和9周的腹脂C18：2含量分别为：14.6%、13.3%、12.6%、10.9%;P=0.001;碘值分别为：67.3、64.4、64.1和62.7）;而当猪的日粮中含有30%DDGS时,在屠宰前0～9周取消DDGS的添加也可以线性的降低猪腹脂的C18：2含量和腹脂碘值（屠宰前的第0-、3-、6-和9周的腹脂C18：2含量分别为：17.3%、16.1%、14.2%和12.4%;P〈0.001;碘值分别为：71.2、68.2、64.5和62.7）。总体来看,当在生长育肥猪中添加高达30%DDGS对猪的生产性能有极小影响,且在屠宰前的3周取消在猪日粮中的DDGS的添加可以降低猪腹脂的C18：2含量和碘值。     

Gaseous emissions,growth performance and pork quality of pigs housed in deep‐litter system compared to concrete‐floor system

This study measured gaseous emissions, growth performance and pork quality in a deep‐litter system and concrete‐floor system. Three hundred and twenty weaned piglets with an average body weight (BW) of 6.0 ± 0.3 kg were assigned randomly into three treatments. Treatments 1 and 2 included four pens with 20 pigs for each pen respectively in the deep‐litter system, and the ratio of sawdust to chaff was 5:5 and 3:7 for treatments 1 and 2 respectively, the probiotics inoculated into the fermentation bedding for both treatments were composed of Saccharomycetes, Bacillus subtilis and Actinomycetes; treatment 3 was the conventional concrete‐floor system including eight pens with 20 pigs for each pen. The concentration of NH₃ and CO₂ in the deep‐litter system was significantly (P < 0.001) lower than that in the concrete‐floor system. The ratio of feed to gain for pigs raised in the deep‐litter system was significantly (P < 0.05) lower than that for pigs housed in the concrete‐floor system. The carcass weight and length, color score and rate of cooking meat for pork from the deep‐litter system were significantly (P < 0.05) higher than those from the concrete‐floor system. Results indicate that pigs raised in the deep‐litter system had some animal welfare improvements and an odor nuisance reduction; in the meantime, pork quality also improved from the deep‐litter system compared to the pigs housed in the concrete‐floor system.     

超微茶粉对生长猪生长性能、胴体品质及脂肪代谢的影响

为了研究超微茶粉对生长猪生长性能、胴体品质及脂肪代谢的影响,将64头50 kg左右的杜长大阉公猪随机分为4组,每组4栏(重复),每栏4头,对照组采食基础日粮,试验组分别添加0.5%、1.0%和1.5%的超微茶粉,试验期70 d,试验结束时计算日增重、料重比,然后屠宰测定分析肌肉胴体品质及脂肪沉积性能。结果表明,超微茶粉对生长猪生长性能没显著影响,并且能显著降低肌内脂肪(IMF)含量,可以显著提高生长猪的瘦肉率和眼肌面积、猪肉肉色以及降低滴水损失和剪切力(P<0.05)。同时,利用前体脂肪细胞研究表没食子儿茶素没食子酸酯(EGCG)对脂肪代谢关键基因表达的影响,结果表明,前体脂肪细胞在EGCG作用下,p-AMPKα蛋白和LPL基因表达显著增加,同时C/EBPβ、SREBP-1、PPARγ基因表达显著降低(P<0.05)。我们的结果提示,超微茶粉对生长猪生长性能没有影响,但可以显著改善肌肉品质,其作用机理可能与对脂肪代谢的调控有关。