脂肪细胞膜免疫技术对动物体脂含量的调控

本文综述了脂肪细胞膜免疫的方法对动物生产性能、屠宰率、胴体品质、血液的影响以及脂肪细胞膜免疫中存在的问题,并展望了脂肪细胞膜免疫的发展方向。     

脂肪细胞膜免疫技术对动物体脂含量的调控

本文综述了脂肪细胞膜免疫的方法对动物生产性能、屠宰率、胴体品质、血液的影响以及脂肪细胞膜免疫中存在的问题，并展望了脂肪细胞膜免疫的发展方向。     

脂肪细胞膜免疫技术的研究进展

本文综述了脂肪细胞膜免疫的种类及其降低动物胴体脂肪的作用机理和效果,阐述了目前存在的问题,并展望了脂肪细胞膜免疫技术的应用前景。     

脂肪细胞膜免疫技术的研究进展

脂肪细胞膜免疫技术是一种降低动物脂肪沉积的新方法。本文从脂肪细胞膜免疫技术的发展历史、技术、种类、作用机理、免疫程序及其对免疫动物的生长性能、胴体品质、体脂沉积和屠宰率等方面免疫效果的研究进展进行了详细综述,最后提出了脂肪细胞膜免疫技术的发展方向和前景展望。     

脂肪细胞膜免疫技术的研究进展

过多的脂肪沉积,不仅降低肉类的质量,也影响人的身体健康,因此人们一直在寻求降低肉品脂肪含量的方法,其中脂肪细胞膜免疫技术就是一种新的b可行的b有效的方法。文章就对脂肪细胞膜免疫作用机理、对动物生产性能、屠宰率、胴体品质等方面的影响以及脂肪细胞膜免疫中存在的问题进行了综述,并展望了脂肪细胞膜免疫的发展方向及应用前景。     

脂肪细胞膜免疫技术的研究进展

过多的脂肪沉积,不仅降低肉类的质量,也影响人的身体健康,因此人们一直在寻求降低肉品脂肪含量的方法,其中脂肪细胞膜免疫技术就是一种新的b可行的b有效的方法.文章就对脂肪细胞膜免疫作用机理、对动物生产性能、屠宰率、胴体品质等方面的影响以及脂肪细胞膜免疫中存在的问题进行了综述,并展望了脂肪细胞膜免疫的发展方向及应用前景.     

应用脂肪细胞膜免疫技术降低动物脂肪的研究进展

如何减少畜禽体内脂肪的过多沉积已成为肉品工业和消费者普遍关注的焦点 ,因此 ,人们一直在寻求降低肉品脂肪含量的方法。脂肪细胞膜免疫技术是一种降低动物脂肪的新方法。该方法是以从动物脂肪细胞膜分离得到的膜蛋白作抗原 ,通过被动免疫或主动免疫来破坏脂肪细胞 ,使脂肪组织中细胞的数量减少 ,限制其贮存脂肪的能力 ,从而达到调控动物生长和降低体脂的目的。虽然有时也会产生一定的副作用 ,但仍具有明显的优点。文章对脂肪细胞膜免疫的方法、作用机理、对动物生产性能、屠宰率、胴体品质、血液的影响以及脂肪细胞膜免疫中存在的问题进行了综述 ,并展望了脂肪细胞膜免疫的发展方向及应用前景     

脂肪细胞膜免疫技术的研究进展

动物体内通过脂肪细胞膜抗体免疫,减少了体脂沉积,从而改善了猪的胴体品质,其关键问题是脂肪细胞膜是否存在特异抗原。起初的试验多以制备多克隆抗体为主。由于抗体特异性较差,可与其他器官发生交叉反应,影响效果。后来发展了脂肪细胞膜单克隆抗体技术,提高了反应特异性,效果较     

脂肪细胞膜免疫调控动物体脂沉积的研究进展

脂肪是动物和人类必需的营养成分 ,在生物体能量代谢中具有重要作用。然而 ,过多脂肪的摄入会引起肥胖 ,诱发多种疾病如高血压、冠心病和糖尿病等。脂肪组织中 ,脂肪是不断合成 (沉积 )和分解 (动员 )的。畜禽体内脂肪代谢受多种因子影响 ,为提高畜禽胴体品质 ,减少动物机体脂肪过量沉积 ,在畜禽脂肪代谢方面的研究一直是一个重要的研究领域。1　脂肪细胞膜 (ａｄｉｐｏｃｙｔｅｐｌａｓｍａｍｅｍｂｒａｎｅＡＰＭ)免疫脂肪细胞膜免疫技术的研究始于 2 0世纪 80年代末 ,它应用的是动物的“天然产品”(抗体 ) ,不会产生应用药物和激素类制剂…     

脂肪细胞膜免疫的研究进展

综述了脂肪细胞膜免疫的研究进展.为今后进一步深入研究脂肪细胞膜免疫与动物的体脂过量沉积之间的关系提供了重要的参考价值.     

Genetic evaluation of carcass yield using ultrasound measures on young replacement beef cattle

Live weight and ultrasound measures of fat thickness and longissimus muscle area were available on 404 yearling bulls and 514 heifers, and carcass measures of weight, longissimus muscle area, and fat thickness were available on 235 steers. Breeding values were initially estimated for carcass weight, longissimus muscle area, and fat thickness using only steer carcass data. Breeding values were also estimated for weight and ultrasound muscle area and fat thickness using live animal data from bulls and heifers, with traits considered sex-specific. The combination of live animal and carcass data were also used to estimate breeding values in a full animal model. Breeding values from the carcass model were less accurate and distributed more closely around zero than those from the live data model, which could at least partially be explained by differences in relative amounts of data and in phenotypic mean and heritability. Adding live animal data to evaluation models increased the average accuracy of carcass trait breeding values 91, 75, and 51% for carcass weight, longissimus muscle area, and fat thickness, respectively. Rank correlations between breeding values estimated with carcass vs live animal data were low to moderate, ranging from 0.16 to 0.43. Significant rank changes were noted when breeding values for similar traits were estimated exclusively with live animal vs carcass data. Carcass trait breeding values estimated with both live animal and carcass data were most accurate, and rank correlations reflected the relative contribution of carcass data and their live animal indicators. The addition of live animal data to genetic evaluation of carcass traits resulted in the most significant carcass trait breeding value accuracy increases for young replacements that had not yet produced progeny with carcass data.     

Genetic and environmental parameters for steer ultrasound and carcass traits

Carcass measurements for weight, longissimus muscle area, 12-13th-rib fat thickness, and marbling score, as well as for live animal measurements of weight at the time of ultrasound, ultrasound longissimus muscle area, ultrasound 12-13th-rib fat thickness, and ultrasound-predicted percentage ether extract were taken on 2,855 Angus steers. The average ages for steers at the time of ultrasound and at slaughter were 391 and 443 d, respectively. Genetic and environmental parameters were estimated for all eight traits in a multivariate animal model. In addition to a random animal effect, the model included a fixed effect for contemporary group and a covariate for measurement age. Heritabilities for carcass weight, carcass longissimus muscle area, carcass fat thickness, carcass marbling score, ultrasound weight, ultrasound longissimus muscle area, ultrasound fat thickness, and ultrasound-predicted percentage ether extract were 0.48, 0.45, 0.35, 0.42, 0.55, 0.29, 0.39, and 0.51, respectively. Genetic correlations between carcass and ultrasound longissimus muscle area, carcass and ultrasound fat thickness, carcass marbling score and ultrasound-predicted percentage ether extract, and carcass and ultrasound weight were 0.69, 0.82, 0.90, and 0.96, respectively. Additional estimates were derived from a six-trait multivariate animal model, which included all traits except those pertaining to weight. This model included a random animal effect, a fixed effect for contemporary group, as well as covariates for both measurement age and weight. Heritabilities for carcass longissimus muscle area, carcass fat thickness, carcass marbling score, ultrasound longissimus muscle area, ultrasound fat thickness, and ultrasound-predicted percentage ether extract were 0.36, 0.39, 0.40, 0.17, 0.38, and 0.49, respectively. Genetic correlations between carcass and ultrasound longissimus muscle area, carcass and ultrasound fat thickness, and carcass marbling and ultrasound-predicted percentage ether extract were 0.58, 0.86, and 0.94, respectively. The high, positive genetic correlations between carcass and the corresponding real-time ultrasound traits indicate that real-time ultrasound imaging is an alternative to carcass data collection in carcass progeny testing programs.     

Prediction of swine carcass composition by total body electrical conductivity (TOBEC)

An experiment was conducted to determine prediction equations that used readings for total body electrical conductivity (TOBEC) in the model for estimation of total fat-free lean and total fat weight in the pork carcass. Ultrasound measurements of live hogs were used to select 32 gilts that represented a range in weight, muscling, and fatness. The TOBEC readings were recorded on warm carcass sides, chilled carcass sides, and the untrimmed ham from the left carcass side. Physical dissection and chemical analyses determined fat-free lean and fat weight of the carcass. All of the ham tissues were analyzed separately from the remainder of the carcass tissues to incorporate ham measurements for prediction of total fat-free lean and total fat weight in the entire carcass. Prediction equations were developed using stepwise regression procedures. An equation that used a warm carcass TOBEC reading in the model was determined to be the best warm TOBEC equation (R2 = 0.91; root mean square error = 0.81). A three-variable equation that used chilled carcass TOBEC reading, chilled carcass temperature, and carcass length in the model was determined to be the best chilled TOBEC equation (R2 = 0.93; root mean square error = 0.73). A four-variable equation that included chilled carcass side weight, untrimmed ham TOBEC reading, ham temperature, and fat thickness beneath the butt face of the ham in the model was determined to be the best equation overall (R2 = 0.95; root mean square error = 0.65). The TOBEC and the fat-free lean weight of the ham are excellent predictors of total carcass fat-free lean weight.     

Genetic and environmental effects on carcass characteristics of Southdown x Romney lambs: I. Growth rate, sex, and rearing effects

Carcass data from more than 4,400 Southdown x Romney ewe and wether lambs collected over a 16-yr period were analyzed for the effects of sex, rearing status, and growth rate. Ewe lambs grew more slowly than wethers and had .78 kg less carcass weight at the same age. The carcass weight advantage for wethers was nearly all caused by heavier fat-free weight. Based on fat depths, the fat on ewe lambs was distributed in more anterior and ventral parts of the carcass relative to wether lambs. Lambs reared as twins had 1.73 kg less carcass weight and correspondingly reduced carcass measurements compared with lambs reared as singles. Sex and rearing status interacted for some traits. However, in no case was a significant sex difference reversed in single- and twin-related lambs. Growth rate effects were determined by regressing average change in carcass measurements on average carcass weight gain over a 5-wk period. When carcass weight remained constant over a 5-wk period, fat weight increased by .12 kg, fat-free weight and muscle measurements decreased, and bone lengths increased. For each kilogram of increase in 5-wk carcass weight gain, the marginal increase in fat weight was .41 kg and that of fat-free weight was .59 kg. At the average 5-wk carcass weight gain of 1.4 kg, fat and fat-free gains were As carcass weight gain increased above 1.4 kg, fat-free gain exceeded fat gain.     

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。     

中国荷斯坦奶公犊不同胴体等级间产肉性能及肉质差异研究

本研究以400头中国荷斯坦奶公犊为试验动物,研究不同胴体等级间产肉性能及肉质差异。对不同胴体等级间产肉性能研究结果发现,除分割肉产率外,其它指标随着等级增加而增大;不同胴体等级间奶公犊的胴体重、分割肉重、优质部位肉重等指标存在显著差异(P<0.05);对不同胴体等级间肉质研究结果发现,不同体形等级间奶公犊肉质差异不显著(P>0.05);随脂肪等级的增加,犊牛肉的蛋白质含量、脂肪含量、感官品质升高,含水量、蒸煮损失、剪切力、色度值L*降低。不同脂肪等级的犊牛肉,除脂肪含量、多汁性存在显著差异外(P<0.05),其它肉质指标均无差异(P>0.05)。试验结果表明,胴体等级能够在一定程度上反映荷斯坦奶公犊的产肉性能,但是对犊牛肉肉质的预测性较低。     

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.     

Genetic parameters for EUROP carcass traits within different groups of cattle in Ireland

The first objective of this study was to test the ability of systems of weighing and classifying bovine carcasses used in commercial abattoirs in Ireland to provide information that can be used for the purposes of genetic evaluation of carcass weight, carcass fatness class, and carcass conformation class. Secondly, the study aimed to test whether genetic and phenotypic variances differed by breed of sire. Variance components for carcass traits were estimated for crosses between dairy cows and 8 breeds of sire commonly found in the Irish cattle population. These 8 breeds were Aberdeen Angus, Belgian Blue, Charolais, Friesian, Hereford, Holstein, Limousin, and Simmental. A multivariate animal model was used to estimate genetic parameters within the Holstein sire breed group. Univariate analyses were used to estimate variance components for the remaining 7 sire breed groups. Multivariate sire models were used to formally test differences in genetic variances in sire breed groups. Field data on 64,443 animals, which were slaughtered in commercial abattoirs between the ages of 300 and 875 d, were analyzed in 8 analyses. Carcass fat class and carcass conformation class were measured using the European Union beef carcass classification system (EUROP) scale. For all 3 traits, the sire breed group with the greatest genetic variance had a value of more than 8 times the sire breed group with least genetic variance. Heritabilities ranged from zero to moderate for carcass fatness class (0.00 to 0.40), from low to moderate for carcass conformation class (0.04 to 0.36), and from low to high for carcass weight (0.06 to 0.65). Carcass weight was the most heritable (0.26) of the 3 traits. Carcass conformation class and carcass fatness class were equally heritable (0.17). Genetic and phenotypic correlations were all positive in the Holstein sire breed group. The genetic correlations varied from 0.11 for the relationship between carcass weight and carcass fatness class to 0.44 for the relationship between carcass conformation class and carcass fatness class. Carcass weight and classification data collected in Irish abattoirs are useful for the purposes of genetic evaluation for beef traits of Irish cattle. There were significantly different variance components across the sire breed groups.     

Isolation and identification of motile Aeromonas species from chicken.

In this study a total of 140 broiler carcasses and carcass parts purchased at different supermarkets in Ankara including 50 whole carcass, 30 wing, 30 leg and 30 breast samples were analysed for the presence of motile Aeromonas species. According to analysis findings, motile Aeromonas spp. were isolated from 116 (82.9%) of total 140 samples. The distribution of the isolates were 94%, 86.6%, 80%, 63.3% in broiler carcass, wing, leg and breast samples, respectively. Aeromonas hydrophila was isolated the most prevalent species with 56% the range followed by Aeromonas sobria with 29.3% and Aeromonas caviae with 14.7% from all of the carcass and carcass part samples, respectively. Consequently, it was supposed that, examined broiler carcass and carcass parts have been contaminated to important level with motile Aeromonas species and it has been risk for public health.     

Effect of carcass price fluctuations on genetic and economic evaluation of carcass traits in Japanese Black cattle

The objectives of this study were 1) to investigate the effect of changes in carcass market prices due to bovine spongiform encephalopathy (BSE) occurrences on estimates of genetic parameters and economic weights for carcass traits; and 2) to compare direct and indirect approaches for prediction of genetic merit of Japanese Black cattle for profitability of their progeny. The direct approach utilized estimated breeding values of carcass prices, whereas in the indirect approach, selection indices were constructed as products of economic weights and breeding values of component traits. Data were composed of 80,191 carcass records divided into 5 periods based on changes in carcass prices as a result of occurrences of BSE in Japan and the United States. The periods ranged from a period before occurrence of BSE in Japan to a period of beef import restrictions and a rise in prices. Carcass traits analyzed included HCW, LM area, rib thickness, subcutaneous fat thickness, and marbling score (MS). Price traits included carcass unit price and carcass sale price. Estimates of heritability for price traits were moderate (0.32 to 0.46) and slightly sensitive to changes in carcass market prices. Genetic correlations of HCW and LM area with price traits increased and that between MS and carcass sale price decreased with period, whereas estimates of genetic correlation between MS and carcass unit price were high in all periods (0.96 to 0.98). Economic weights for carcass traits varied with periods because carcass prices were highly sensitive to economic importance of traits. Nevertheless, correlations between within-period breeding values for price traits estimated using direct and indirect approaches were high (0.92 to 0.99). This result indicates that selection realized by direct and indirect approaches will provide very similar results. A comparison among within-approach breeding values estimated in different periods showed that the largest differences in breeding values of sires for price traits were between the periods after occurrences of BSE in Japan and in the United States. Economic effects of BSE occurrences influenced the importance of carcass traits and economic merits of price traits through a change of carcass prices from period to period, irrespective of the approach taken in determining the genetic merit of breeding animals for profitability of their progeny.