育肥猪出栏前去掉预混料对猪胴体与肉品质的影响

为探讨育肥猪出栏前不同时间去掉预混料对胴体和肉品质的影响,选用180头体重为80kg左右的杜长大三元杂交育肥猪,随机分成3组(对照组、试验1组、试验2组),每组3个重复(圈),每重复(圈)20头。对照组饲喂含有4%商业预混料的日粮,试验1组宰前2周饲粮中去掉预混料(用沸石粉代替预混料),试验2组宰前4周饲粮中去掉预混料(用沸石粉代替预混料)。屠宰后测定并比较各组猪只的胴体品质和肉品质指标。结果表明:宰前不同时间去掉预混料对猪胴体品质、肉品质均无显著影响(P>0.05)。研究结果为减少生猪养殖过程中的粪污排放对环境的污染以及降低生产成本提供了有益参考。     

瘦肉型猪胴体品质和肌肉品质测定

选取适宰期大约克,长白纯种猪,社长大,长大,汉长大,大杜长,长大二（二花脸）杂种猪进行屠宰测定和肌肉品质常规分析。研究表明,大多数胴体性状和肌肉品质不存在非常显著的组合间差异。胴体品质总体而言比国外瘦肉型猪略差,但肌肉品质倨于国外报道的肉质性状。长大二三元杂交猪胴体品质和肉质性状与其它组合间差异不大。     

大巴沙猪胴体性状和肉质性状研究及相关性分析

试验旨在对大约克×(巴克夏×沙子岭)(简称大巴沙)猪的胴体性状和肉质性状进行评估。选取99头大巴沙猪进行屠宰测定,主要测定屠宰率、胴体长、背膘厚、眼肌面积和瘦肉率等胴体性状及pH、肉色、大理石纹和肌内脂肪等肉质性状。结果表明,大巴沙猪的屠宰率和瘦肉率分别为72.24%和59.22%,系水力损失和肌内脂肪含量分别为93.16%和2.90%。性状间相关性分析表明,大巴沙猪宰前活重与胴体重、胴体长、眼肌面积呈极显著正相关(P<0.01),与屠宰率、pH1、肌苷酸含量呈显著正相关(P<0.05),与嫩度呈极显著负相关(P<0.05),并构建了宰前活重与相关指标的回归方程。研究结果表明,大巴沙猪胴体性状优良、肌肉保水力强、肉质鲜美,可通过宰前活重快速估测屠宰率、胴体长、眼肌面积、肌内脂肪含量,大大节省屠宰测定成本。     

pGRF基因质粒对猪胴体性状和肌肉品质的影响

为研究猪生长激素释放因子(pGRF)基因质粒对猪胴体性状和肌肉品质的影响,试验选用24头大白×长白二元杂交去势公猪平均体重(17.25±0.62)kg,随机分为4个处理,每个处理6个重复,分别经臀部注射0、4.0 mg、6.0 mg和8.0 mg的pGRF基因质粒。结果表明:注射4.0 mg和6.0 mg的pGRF基因质粒有提高猪宰前活重、眼肌面积、屠宰率、胴体直长、胴体斜长及降低背膘厚的趋势,其中6.0 mg组宰前活重和胴体斜长与对照组相比差异显著(P0.05)。注射pGRF基因质粒对猪肌肉品质无显著影响(P0.05)。     

快进快宰制在猪屠宰检疫中的应用

快进快宰制是指在屠宰检疫中，尽量缩短屠宰猪经检疫合格后进入待宰圈至宰杀时的时间，即尽量缩短屠宰猪在待宰圈的待宰时间，快进快宰制的重要意义在于有效地降低了过去因待宰时间长，导致的宰前发病率高和宰后检出病害胴体率高以及急宰现象多的缺点，大大提高了出厂肉品的品质。     

宁乡猪不同杂交组合的胴体性能和肉质性状分析

为了分析和比较宁乡猪不同杂交组合猪的胴体性状和肌肉品质,试验随机选择达上市体重的皮特兰×宁乡猪(皮宁)7头和皮特兰×(巴克夏猪×宁乡猪)(皮巴宁)4头进行屠宰,测定了眼肌面积、瘦肉率、肌内脂肪、氨基酸、脂肪酸、微量元素等多项胴体及肉质性状指标,并分析其差异性。结果表明,胴体重、屠宰率、3点平均背膘厚、瘦肉率、肥膘率、十七烷酸、α-亚麻酸和总不饱和脂肪酸等8项指标组间差异达到了显著水平(P0.05),其他各项指标组间差异不显著(P0.05)。说明皮宁组合和皮巴宁组合猪均表现出了良好的胴体性能和肌肉品质。     

猪胴体淋巴结的剖检选择及其重要意义

淋巴系统在肉品检疫中具有重要意义,它所表现的变化,不仅是评价肉品卫生质量的重要依据,而且是病畜发病的重要指标。因此每个兽医卫生工作者,不仅要熟知屠畜淋巴结分布情况,而且需要了解淋巴液的流向,以便在屠畜的宰后检疫中选择有代表性的淋巴结进行剖检,从而提高肉品卫生检疫水平,达到肉品的放心和安全。各地关于猪宰后胴体剖检淋巴结的操作,不甚统一,笔者根据实践中的体会,对猪宰后胴体剖检淋巴结提出一点看法。以供参考。1猪胴体宰后剖检淋巴结的选择“四部规程”第三章第十九条(二)中规定:“在肉尸检疫中,猪主要剖检腹股沟浅淋巴结及腹…     

定远猪胴体和肉质性状测定及分析

通过测定定远猪屠宰胴体性状及肉品质,以期为定远猪遗传资源的保护及开发利用提供理论依据。试验选择10月龄定远猪12头进行屠宰,测定胴体性状及肉质性状,并进行变异系数与相关性分析。结果显示,定远猪平均体重达89.69 kg,背膘厚3.74 cm,屠宰率达76.29%,瘦肉率为48.47%,腿臀比为29.12%,肉色评分为3.33,大理石纹评分3.29,眼肌面积为26.09 cm2,失水率为20.94%,肌内脂肪含量为4.87%,拿破率为74.36%。宰后45 min pH为6.16,24 h时降为5.56。定远猪屠体平均背膘厚、皮厚、眼肌面积和肌内脂肪含量等指标变异系数较大。综上表明,定远猪屠宰率较高,肉质好,但肌内脂肪含量及背膘厚变异系数较高,可在后期保种过程中适当进行选育,提高定远猪的一致性。     

有机铬对猪胴体品质及血液生化指标的影响

影响肉质的因素很多,主要包括遗传、营养、屠宰前的饲养管理、屠宰的技术以及在出售前的冷冻等。由于很多营养物质都参与肉质变化的代谢和生化过程,因此,营养在肉质的调控中起着重要作用。一些研究表明,在猪饲粮中添加有机铬可提高猪的瘦肉率、日增重和饲料转化率,降低胴体脂肪含量,改善猪肉品质。为此,现着重论述日粮中铬对猪胴体品质及血液生化指标的影响。1有机铬对猪胴体品质的影响有机铬能显著改善猪的胴体品质。陈代文等[1]在肥育猪日粮中添加有机铬对猪的屠宰性能无显著影响,但眼肌面积和瘦肉率分别提高6.73%和1.60%,皮脂率下降1.60%…     

杜湘猪、杜圩猪横交后代生产性能比较分析

本研究对杜湘猪、杜圩猪横交后代繁殖、生长、胴体与肉质性状进行测定。结果表明,杜湘猪母猪较杜圩猪母猪体躯更长,背膘相对较厚,但背腰较长而窄;初产繁殖性能及胴体性状两者差异不显著;在肉质性状上,由于杜湘猪宰前活重极显著高于杜圩猪,脂肪沉积更加充分,使得大理石纹评分高于杜圩猪,其余指标均表明两者肉质优良。通过横交,毛色分离比例下降,但在繁殖、生长、肉质性状等方面仍存在整齐度低、一致性差等问题,还需进一步选育提高。     

Relationships among serum characteristics and performance and carcass traits in growing pigs

Twelve blood serum components were determined on 78 barrows and 66 gilts, serially slaughtered at six age groups, starting at 69 d, at 2-wk intervals. One-half of the animals were fed ad libitum and one-half were fed "time restricted". Partial correlations between production and carcass traits and serum components were calculated from the residuals of the least-squares analysis. Calcium, serum protein and albumin were highly (P less than .01) correlated with several production and carcass traits. Creatinine was positively correlated (P less than .05) with backfat, loin fat, and percent dissected muscle and bone. Alkaline phosphatase showed a positive relationship with average daily gain (P less than .05) and percent dissected bone (P less than .01). A stepwise regression analysis was used to examine simultaneously the relative predictive value of the blood serum components. The nitrogenous compounds, which included albumin, total protein, urea and creatinine, were the most important predictors of performance (avg daily gain, feed conversion) and carcass composition. However, most of the serum components were not related to the performance and carcass composition traits.     

Genetic parameters of serum vitamin A and total cholesterol concentrations and the genetic relationships with carcass traits in an F1 cross between Japanese Black sires and Holstein dams

Blood sample and carcass trait data were collected from 841 and 3,219 fattening animals of an F(1) cross between Japanese Black sires and Holstein dams, respectively. Data on serum vitamin A and total cholesterol concentrations containing 582 to 739 records at 4 stages of beef-fattening production were used to estimate variance components and heritabilities for the 2 traits, based on fattening periods: less than 13 mo of age (stage 1), 14 to 18 mo of age (stage 2), 19 to 21 mo of age (stage 3), and greater than 22 mo of age (stage 4). Furthermore, the genetic correlations of serum vitamin A and total cholesterol concentrations with beef marbling standards, carcass weight, ribeye area, rib thickness, and subcutaneous fat thickness were estimated. The heritability estimates of serum vitamin A concentration were consistently and drastically decreased from 0.37 ± 0.15 to 0.07 ± 0.07 from stages 1 to 4 because of considerable decreases in sire variances, whereas the residual variances remained large and stable throughout all 4 stages. Serum total cholesterol concentration was moderately heritable (approximately 0.35 to 0.64) throughout all 4 stages. The genetic correlations among serum vitamin A concentrations and beef marbling standards were high and negative (-0.94) in stage 4. The genetic correlations between serum vitamin A concentration and carcass weight in stages 3 and 4 were moderate and positive (approximately 0.26 to 0.36). Moderate to high positive genetic correlations between serum vitamin A concentration and subcutaneous fat thickness were obtained throughout the stages (approximately 0.40 to 0.75). Genetic correlations of serum total cholesterol concentration with carcass weight and rib thickness were moderate and positive (approximately 0.29 to 0.46) in stages 2, 3, and 4. These results indicate serum vitamin A and total cholesterol concentrations could be effective physiological indicators for improving carcass traits.     

Effect of breed-type and feeding regimen on goat carcass traits

Meat-type (Boer x Spanish and Spanish) goats from two feeding regimens (feedlot and range) were slaughtered and live and carcass weights were obtained. At 24 h after death, various yield and quality measurements were collected. One side from each carcass was fabricated into major wholesale cuts for dissection into major carcass components. Feedlot goats had heavier (P<.05) live and carcass weights and carcasses that yielded more (P<.05) dissectible fat and lean and less (P<.05) bone, as a percentage of carcass weight, than did the carcasses of range goats. In the feedlot environment, Boer x Spanish goats had greater (P<.05) live weights, carcass weights, actual and adjusted fat thicknesses, carcass conformation scores, and leg circumference scores than did Spanish goats of similar age. The only breed-type differences that were significant after adjusting for live weight using analysis of covariance were that Boer x Spanish goats in the feedlot treatment had greater (P<.05) actual and adjusted fat thickness and carcass conformation than Spanish goats on the feedlot treatment. The Boer x Spanish goat carcass trait advantage could mainly be attributed to their larger size and enhanced capacity for growth.     

Effects of different rearing systems on growth performance,carcass traits,meat quality and serum biochemical parameters of Chaohu ducks

This study was conducted using a total of 360 22‐day‐old Chaohu ducks to evaluate the effect of rearing system on growth performance, carcass traits, meat quality and serum parameters of male and female Chaohu ducks. The birds were divided and raised in separate pens according to sex and rearing system, with three replicate pens of 30 male or 30 female ducks per pen for each rearing system. The rearing systems consisted of a floor rearing system (FRS) and a net rearing system (NRS). Results showed that ducks raised in NRS had better growth performance, whereas, ducks raised in FRS exhibited better carcass traits and meat color, and lower intramuscular fat. For the serum parameters, NRS significantly decreased high‐density lipoprotein cholesterol content, and enhanced total protein and triacylglycerol contents. Male ducks had lower abdominal fat percentage, and higher growth performance and shear force, but there were no other significant differences between sexes. No rearing system × sex interaction was observed in the present study, revealing that rearing system had the same effect on both sexes. In conclusion, NRS was beneficial to the growth performance of Chaohu ducks, whereas this system had some negative effects on carcass traits, meat quality and serum profiles.     

宁乡猪及杜宁二元杂种猪的胴体与肉质性状测定

为评价宁乡猪和杜洛克猪的杂交效果,本实验分别测定了91头宁乡猪和76头杜宁二元杂种猪的胴体性状和肉质性状指标,并对不同性状指标进行相关性分析。结果表明:在胴体性状方面,与宁乡猪相比,杜宁二元杂种猪的体直长、体斜长、胴体重、肋骨数和眼肌面积极显著提高,背膘厚和皮厚极显著降低;在肉质性状方面,杜宁二元杂种猪的肉色红度(a^*)、pH_45min和熟肉率极显著高于宁乡猪,pH24h显著低于宁乡猪。相关性分析显示,宁乡猪体斜长和胴体重存在极显著正相关(r=0.71),a^*值与黄度(b^*)值之间存在高度正相关(r=0.58);杜宁二元杂种猪体直长与体斜长存在极显著正相关(r=0.64),亮度(L^*)值与b值极显著相关(r=0.54)。说明杜宁二元杂种猪在导入杜洛克血缘后,其胴体性状较宁乡猪得到较大改善,但肉质性状改善效果不明显。     

Candidate serum metabolite biomarkers of residual feed intake and carcass merit in sheep

Mutton and lamb sales continue to grow globally at a rate of 5% per year. However, sheep farming struggles with low profit margins due to high feed costs and modest carcass yields. Selecting those sheep expected to convert feed efficiently and have high carcass merit, as early as possible in their life cycle, could significantly improve the profitability of sheep farming. Unfortunately, direct measurement of feed conversion efficiency (via residual feed intake [RFI]) and carcass merit is a labor-intensive and expensive procedure. Thus, indirect, marker-assisted evaluation of these traits has been explored as a means of reducing the cost of its direct measurement. One promising and potentially inexpensive route to discover biomarkers of RFI and/or carcass merit is metabolomics. Using quantitative metabolomics, we profiled the blood serum metabolome (i.e., the sum of all measurable metabolites) associated with sheep RFI and carcass merit and identified candidate biomarkers of these traits. The study included 165 crossbred ram-lambs that underwent direct measurement of feed consumption to determine their RFI classification (i.e., low vs. high) using the GrowSafe System over a period 40 d. Carcass merit was evaluated after slaughter using standardized methods. Prior to being sent to slaughter, one blood sample was drawn from each animal, and serum prepared and frozen at −80 °C to limit metabolite degradation. A subset of the serum samples was selected based on divergent RFI and carcass quality for further metabolomic analyses. The analyses were conducted using three analytical methods (nuclear magnetic resonance spectroscopy, liquid chromatography mass spectrometry, and inductively coupled mass spectrometry), which permitted the identification and quantification of 161 unique metabolites. Biomarker analyses identified three significant (P < 0.05) candidate biomarkers of sheep RFI (AUC = 0.80), seven candidate biomarkers of carcass yield grade (AUC = 0.77), and one candidate biomarker of carcass muscle-to-bone ratio (AUC = 0.74). The identified biomarkers appear to have roles in regulating energy metabolism and protein synthesis. These results suggest that serum metabolites could be used to categorize and predict sheep for their RFI and carcass merit. Further validation using a larger (3×) and more diverse cohort of sheep is required to confirm these findings.     

Genome-wide mapping and identification of new quantitative trait loci affecting meat production, meat quality, and carcass traits within a Duroc purebred population

Most QTL detection studies in pigs have been carried out in experimental F(2) populations. However, segregation of a QTL must be confirmed within a purebred population for successful implementation of marker-assisted selection. Previously, QTL for meat quality and carcass traits were detected on SSC 7 in a Duroc purebred population. The objectives of the present study were to carry out a whole-genome QTL analysis (except for SSC 7) for meat production, meat quality, and carcass traits and to confirm the presence of segregating QTL in a Duroc purebred population. One thousand and four Duroc pigs were studied from base to seventh generation; the pigs comprised 1 closed population of a complex multigenerational pedigree such that all individuals were related. The pigs were evaluated for 6 growth traits, 7 body size traits, 8 carcass traits, 2 physiological traits, and 11 meat quality traits, and the number of pigs with phenotypes ranged from 421 to 953. A total of 119 markers were genotyped and then used for QTL analysis. We utilized a pedigree-based, multipoint variance components approach to test for linkage between QTL and the phenotypic values using a maximum likelihood method; the logarithm of odds score and QTL genotypic heritability were estimated. A total of 42 QTL with suggestive linkages and 3 QTL with significant linkages for 26 traits were detected. These included selection traits such as daily BW gain, backfat thickness, loin eye muscle area, and intramuscular fat content as well as correlated traits such as body size and meat quality traits. The present study disclosed QTL affecting growth, body size, and carcass, physiological, and meat quality traits in a Duroc purebred population.     

Comparison of carcass composition among Japanese Black, Holstein and their crossbred steers fattening on farm

Carcass composition among Japanese Black, Holstein and their crossbreed (F1), by Holstein mated with Japanese Black sires, was compared by using carcass components of fattening steers collected at eight carcass processing factories. The least squares means of 14 retail cuts, total weights of retail cuts, trimmed fat and bones, and six carcass traits measured at 6th?7th rib section were used for the comparison and examined the expression of heterosis. The comparison was performed at the same level of left‐side carcass weight and under 10 mm fat cover on each retail cut. Japanese Black had the heaviest total weight of retail cuts, followed by F1 and then Holstein. By contrast, non‐edible parts, trimmed fat and bones, were heavier in the order of Holstein, F1 and Japanese Black. Of the retail cuts, so called higher‐priced cuts, such as Shoulder‐Chuck‐Roll, Tender‐Loin, Rib‐Chuck‐Roll, Strip‐Loin and Sirloin‐Butt surrounding the spinal column, were heavier in Japanese Black than Holstein. Although F1 showed intermediate values for almost all traits, Tender‐Loin, Rib‐Chuck‐Roll and Strip‐Loin of F1 were similar to those of Japanese Black rather than the mid‐parent averages. It reflects that at least the average parent heterosis of 2.3–4.3% might be expressed in these higher‐priced cuts. The classification of breeds was carried out by the canonical discriminant analysis using 20 carcass measurements. By the canonical variates, breeds can be effectively discriminated with misdiscrimination rate of 11.6%. When the comparison is made at the carcass weight constant, Japanese Black has characteristics for producing superior carcass quality as well as meat quality.     

Genetic parameters for carcass composition and pork quality estimated in a commercial production chain

Breeding goals in pigs are subject to change and are directed much more toward retail carcass yield and meat quality because of the high economic value of these traits. The objective of this study was to estimate genetic parameters of growth, carcass, and meat quality traits. Carcass components included ham and loin weights as primal cuts, which were further dissected into boneless subprimal cuts. Meat quality traits included pH, drip loss, purge, firmness, and color and marbling of both ham and loin. Phenotypic measurements were collected on a commercial crossbred pig population (n = 1,855). Genetic parameters were estimated using REML procedures applied to a bivariate animal model. Heritability estimates for carcass traits varied from 0.29 to 0.51, with 0.39 and 0.51 for the boneless subprimals of ham and loin, respectively. Heritability estimates for meat quality traits ranged from 0.08 to 0.28, with low estimates for the water holding capacity traits and higher values for the color traits: Minolta b*(0.14), L* (0.15), a* (0.24), and Japanese color scale (0.25). Heritability estimates differed for marbling of ham (0.14) and loin (0.31). Neither backfat nor ADG was correlated with loin depth (r(g) = 0.0), and their mutual genetic correlation was 0.27. Loin primal was moderately correlated with ham primal (r(g) = 0.31) and more strongly correlated with boneless ham (r(g) = 0.58). Backfat was negatively correlated with (sub)primal cut values. Average daily gain was unfavorably correlated with subprimals and with most meat quality characteristics measured. Genetic correlations among the color measurements and water-holding capacity traits were high (average r(g) = 0.70), except for Minolta a* (average r(g) = 0.17). The estimated genetic parameters indicate that meat quality and valuable cut yields can be improved by genetic selection. The estimated genetic parameters make it possible to predict the response to selection on performance, carcass, and meat quality traits and to design an effective breeding strategy fitting pricing systems based on retail carcass and quality characteristics.     

半番鸭产肉性能、肉品质和血液生化指标间的典型相关分析

对半番鸭产肉性状、肉品质性状与血液生化指标等3组性状14个变量进行典型相关分析。结果表明:产肉性状与血液生化指标间的第1个典型相关系数达极显著水平(P<0.05),占2组性状间总相关信息的48.3%,其典型相关系数为0.697;肉品质性状与产肉性状和血液生化指标间的第1个典型相关系数达显著水平(P<0.05),分别占2组性状间总相关信息的35.8%和20.8%,其典型相关系数分别为0.599、0.531。在3组性状中屠体重、全净膛重、失水率、肉色、pH值、血清总蛋白含量、白蛋白含量和甘油三酯含量起主要作用。