Carcass Traits, Meat Yield and Primal Meat Cuts from Arsi, Harar, Ogaden and F1 Jersey*Horro Crossbred Bulls Fed Corn Silage Based Similar Finishing Diet

This study was conducted with the objective to determine carcass traits, meat yield, and primal meat cuts of Arsi, Harar, Jersey*Horro crossbred, and Ogaden cattle breeds at Haramaya University, Ethiopia. A total of 12 bulls of four cattle breeds (3 Arsi, 3 Harar, 3 F1 Jersey*Horro crossbred and 3 Ogaden) with almost similar ages were randomly assigned to four treatments in a completely randomised design (CRD). Data on carcass traits, meat yield, and primal meat cuts were analyzed using the General Linear Model (GLM) of the Statistical Analysis Software (SAS) 9.4 version. The overall averages of live body weight, hot carcass weight, chilled carcass weight, dressing percentages based on hot carcass weight, and rib eye area of experimental cattle breeds were 215.58 kg, 102.93 kg, 99.56 kg, 47.61%, and 8.13 inch2, respectively. The hot carcass weight and chilled carcass weight of the Ogaden (136.57;133.30 kg, resp.) breed were higher (p < 0.01) compared to other experimental cattle breeds. Dressing percentages based on hot carcass weight were higher (p < 0.05) for the Ogaden (49.61%) and Arsi (49.82%) cattle breeds compared to Harar and Jersey*Horro crossbred (45.73%, 45.27%, resp.) cattle breeds. The average meat yield and proportion of meat yield of cattle breeds were 77.52 kg and 77.46%, respectively. With a linear regression coefficient of prediction (R2) ranging from 52.26% to 93.58%, primal meat cuts significantly (p dicted meat yield. In conclusion, the breed of cattle had a significant (p 0.05) influence on live body weight, hot and chilled carcass weight, dressing percentage, rib eye area, subcutaneous fat thickness, meat yield, and the weights of most primal meat cuts. The Ogaden cattle breed had a higher and better meat yield, carcass traits, and most primal meat cuts compared to other experimental cattle breeds. Furthermore, the inclusion of corn silage in the diet of fattening bulls improved the carcass and meat yield. Therefore, the performance of Ogaden cattle compared to other and previous studies suggests the possibility of using this breed for export purposes in addition to Borana and Harar cattle breeds in the future.

Seasonal variation in the biochemical composition,condition index,and meat yield of the non-indigenous pearl oyster Pinctada imbricata radiata(Leach,1814)from the West of the Aegean Sea,Greece

The average values of the seasonal flesh biochemical composition(%)of the pearl oyster Pinctada imbricata radiata originated form 2 sampling sites,the gulfs of Evoikos(E)and Saronikos(S)in the Western Aegean Sea,showed that is rich in proteins(64.00±1.86-(E),64.67±2.95-(S))with low fat content(10.96±1.04-(E),11.86±1.13-(S))and carbohydrates(13.29±2.48-(E),9.94±4.32(S)).The condition index ranged from 26.16%±5.04 in the autumn in(E),to 44.73%±7.50 in the summer in(S).The meat yield varied from 20.49%±3.20%in the summer in(E)to 30.73%±3.47%in the summer in(S).Both results demonstrate the high nutritional profile of the pearl oyster,supporting its suitability as a potential new Mediterranean seafood source for human consumption.

Effect of Age and Breeds of Cattle on Carcass and Meat Characteristics of Arsi, Boran, and Harar Cattle in Ethiopia

The objective of this study was to determine the effect of age and breed of cattle on carcass and meat characteristics in Ethiopia. A total of 39 (Arsi 11, Boran 14 and Harar 14) cattle breeds with age categories of <3, 4 - 6, and 7 - 9 years were used for the study. The bulls were purchased from their respective production system of mixed crop livestock system (Arsi and Harar) and Ranch (Boran). Parameters such as live and carcass weight, meat yield percent, fat characteristics, and primal beef cuts were evaluated. Complete randomized design was used for the study. The live weight of bulls at <3, 4 - 6 and 7 - 9 years ranged 135 - 183, 167 - 181, and 155 - 433 kg, respectively. The carcass weight, dressing percentage, meat yield percent, forequarter, hindquarter, rib eye area, and fat thickness ranged 57 - 209.73 kg, 41.8% - 51.6%, 32% - 58%, 11.7 - 56.42 kg, 14.04 - 45.34 kg, 4.78 - 10.25 square inches and 0.18 - 0.38 inches, respectively. At an early age category (<3 years) meat yield percentage of Arsi, Boran and Harar breeds were 50.86, 30 and 18.72, respectively, and as age category shifted from one age category to the next Harar increased by 13× and Boran by 2.9× and Arsi decreased by -0.93×. The mean rib percentage of Arsi, Boran and Harar were in the range of 7.98 - 9.57, 8.62 - 10.44 and 7.08 - 8.83, respectively. Breed and age of bulls had significantly affected primal meat cuts. Meat yield was predicted from live and hot carcass weight with coefficient determination (R2) of 70.66% and 74.75%, respectively. From the study, it was concluded that age and breeds of cattle had significantly influence on carcass and meat characteristics. Therefore, to determine whether variations were due to genetic or environmental cause’s evaluation of the three breeds under similar feeding condition was recommended.

Carcass and Meat Characteristics of Bulls from Arsi, Boran, Harar and Holstein Frisian Crosses Cattle Breeds Finished under Similar Level of Concentrate Supplementation

A study was conducted to evaluate the effect of age and breeds (Arsi, Borana, HF-Cross and Harar) on carcass and meat characteristics of bulls finished under similar feeding conditions. The feeding experiment was conducted for 90 days at Beef farm of Haramaya University. In this experiment, 24 bulls were fed with roughage (60%) which contained grass hay and wheat straw and concentrate (40%) which contained wheat bran, noug (gucia abysica) cake, maize grain, limestone, salt and ruminant premix. The bulls were transported to Bishoftu ELFORA export abattoir for slaughter following the procedure of the abattoir. The result of the study revealed that the average slaughter weight, hot carcass weight, cold carcass weight, shrink loss, commercial dressing and true dressing percentage were 179.1 kg, 86.8 kg, 82.7 kg 4.7%, 48.8% and 78.3%, respectively. Total edible and nonedible offal were significantly (P < 0.01) influenced by breed and age. Pelvic fat was significantly (P < 0.01) influenced by breeds. Meat yield percentages of Arsi, Boran, Harar, and HF-crossbred were 78.1%, 77%, 72.8% and 77.2% respectively. Meat yield was predicted from fat thickness and ribeye area with 61% accuracy. Arsi bulls attained the highest (78%) meat yield at early age but decreased by 0.713 rate as age of animals advanced by one digit whereas the meat yield from other breeds showed increment in meat yield percentage with the rate of 1.98, 1.1 and 0.1 for cross, Borana and Harar breed bulls, respectively as age advanced. Yield from fore shank, sirloin, top and bottom sirloin primal cuts were affected by breed. Arsi breed had higher meat bone ration than cross breed. Retailed meat yield was significantly (P < 0.001) predicted from rib area and subcutaneous fat thickness (P < 0.001) with a coefficient of determination 61%, from live animal trait and primal cuts with a coefficient of determination 89.56% and 94.78% respectively. Arsi bulls can be used for beef purpose at 2 - 3 years, as the meat percentage decreases thereafter;while bulls from Boran, cross breed and Harar breeds can be used up to 5 years of age. Meat to bone ratio indicated that HF-Crossbred was less appropriate for beef purpose than other breed bulls in this study. The rate of pH decline was not influence (P > 0.05) by age and breed in the current study.

克氏原螯虾食用品质表观性状分析与评价

克氏原螯虾是我国养殖面积最大、养殖产量最高的淡水虾类,其食用品质一直备受关注。以淮安地区的克氏原螯虾为研究对象,分析了肥满度、躯体结构比例、含肉率、脏器指数等食用品质表观性状与规格、月份和性别的相关性。研究发现,规格、月份和性别对克氏原螯虾的食用品质表观性状均具有重要影响。克氏原螯虾规格越大,尾部重量占比越小,含肉率越低。5月份克氏原螯虾的含肉率和肝胰腺指数最高;而10月份克氏原螯虾含肉率和肝胰腺指数最低。雄虾螯足重量占比和头胸部重量占比显著性大于雌性(P<0.05),尾部重量占比和含肉率显著性小于雌虾(P<0.05)。研究结果可为克氏原螯虾消费和生产提供双重指导。

4种常见帘蛤目贝类表观性状与出肉率通径分析

为探究青蛤(Cyclina sinensis)、菲律宾蛤仔(Ruditapes philippinarum)、等边浅蛤(Macridiscus aequilatera)、四角蛤蜊(Mactra veneriformis)的表观性状与出肉率的关系,对这4种贝类随机抽样40~50个进行解剖,测量壳长、体质量、软体质量、壳质量4个性状参数,计算出肉率并进行正态检验,运用相关分析法和通径分析法对表观性状与出肉率的相关性进行研究。结果显示,菲律宾蛤仔、青蛤的壳长性状对出肉率总通径系数分别为0.391、0.394;建立的菲律宾蛤仔、四角蛤蜊、青蛤壳长和体质量对出肉率的回归方程的决定系数分别为0.414、0.119和0.221。结果表明,运用表观性状来进行上述4种贝类出肉率性状的选育存在可行性。

淮南麻黄鸡屠宰性能与肌肉部分品质的研究

研究60日龄淮南麻黄鸡的屠宰性能和肌肉部分品质。结果表明:淮南麻黄鸡的活重、屠宰率、半净膛率、全净膛率、胸肌率和腿肌率分别为877.2g、84.57%、74.72%、60.76%、20.68%和20.25%,且公鸡显著高于母鸡(P<0.05)。公、母仔鸡间肌肉主要品质差异不显著;而在同一性别内,胸肌的红度极显著低于腿肌、亮度高于腿肌;胸肌的失水率、蒸煮损失、贮存损失及粗蛋白含量高于腿肌,腿肌的粗脂肪含量较高。肌纤维直径为28.59～29.59μm。淮南麻黄鸡的肉质优良。

克氏原螯虾和红螯螯虾出肉率与可量性状的相关性

为寻找合理的方法评估比较克氏原螯虾和红螯鳌虾出肉率的高低,从而为其选育工作提供科学依据,运用统计分析方法研究了2种虾的出肉率和可量性状之间的相关性。结果表明:红螯螯虾出肉率高于克氏原螯虾出肉率,第1腹节宽为影响克氏原螯虾出肉率的重点性状;体长和头胸甲长为影响红螯螯虾出肉率的重点性状,全长次之。得出结论:(1)可量性状与出肉率的相关性相较于可量性状与肉质量的相关性更能突出重点性状;(2)通过测量可量性状或通过性状比值进行克氏原螯虾和红螯螯虾出肉率方面的选育都是可行的。

阿勒泰羊MyoD基因的遗传多态性及其与产肉性状的关联分析

利用分子生物学手段研究MyoD基因遗传多态性与阿勒泰羊产肉量的关系,旨在为今后用分子标记辅助育种方法提高阿勒泰羊产肉性能提供科学依据。本试验以120只阿勒泰羊周岁公羊为研究对象,选取MyoD基因的5′调控区和外显子1的部分片段,采用PCR-SSCP技术检测其遗传多态性,并与周岁体重进行关联分析,研究MyoD基因的多态性与阿勒泰羊产肉性能的关系。结果表明,MyoD-P1基因座(MyoD基因5′调控区)无多态性;MyoD-P2基因座(外显子1)有多态性,存在3种基因型:AA、AB和BB,测序结果显示该处发生了碱基突变A→G,为错义突变,该突变导致其编码的氨基酸由组氨酸变为丙氨酸,经关联分析发现,该突变对阿勒泰羊产肉性能有显著影响(P<0.05)。阿勒泰羊MyoD基因外显子1上的点突变可能是影响阿勒泰羊产肉性能的重要位点,MyoD基因可望作为阿勒泰羊产肉性能的候选基因。

南极磷虾捕捞初期适宜挤压脱壳工艺参数

为了验证南极磷虾挤压脱壳设备的生产效果、完善并优化船上挤压脱壳生产工艺,该文开展了不同进料速度、原料放置时间和预冷时间对得肉率和虾壳残留率影响的研究。结果表明,对于刚捕捞后未经处理的磷虾,试验设备脱壳效果理想,得肉率约为25%、虾壳残留约为5%;放置时间在120 min以内的磷虾均可用作脱壳磷虾肉的生产,越新鲜的磷虾脱壳后得到的磷虾肉品质越好;对原料进行预冷来延长品质保持时间是保证产品质量的有效方法;冷冻后磷虾得肉率明显降低,实际生产中不建议采用。研究结果可为南极磷虾脱壳技术的应用和产业化提供参考。

不同性别肉鸡生长速度、产肉性能、骨骼矿化和器官发育的差异

试验研究了不同性别肉鸡生长速度、产肉性能、骨骼矿化和器官发育的差异。将1日龄健康罗斯308肉鸡公雏和母雏各50只分别随机分为5个重复,每重复10只。试验期为42 d。结果显示:(1)1～21、22～42 d和1～42 d肉鸡公鸡体增重和饲料效率显著高于母鸡(P<0.05),22～42 d和1～42 d肉鸡公鸡采食量显著高于母鸡(P<0.05),1～21 d肉鸡公鸡采食量与母鸡无显著差异(P>0.05);(2)42 d公鸡的胴体重、胸肉重和腿肉重均显著高于母鸡(P<0.05),公鸡胴体率和腿肉率显著低于母鸡(P<0.05),公鸡和母鸡胸肉率无显著差异(P>0.05);(3)42 d公鸡胫骨强度、胫骨重量和胫骨灰分重量均显著高于母鸡(P<0.05),胫骨长度、直径、灰分含量及钙、磷含量在公鸡与母鸡间无显著差异(P>0.05),公鸡与母鸡血浆钙、磷含量无显著差异(P>0.05);(4)42 d公鸡肝脏重量和小肠重量显著高于母鸡(P<0.05),心脏和脾脏重量在公鸡、母鸡间无显著差异(P>0.05)。由此可见,1～42 d肉鸡公鸡生长速度、胴体重量、胫骨质量及肝脏、小肠重量均高于母鸡,但胴体率和腿肉率低于母鸡。

巴美肉羊生长发育和胴体等级肉产量研究

选择4、6、8月龄巴美肉羊各10只,与同月龄的小尾寒羊、苏尼特羊进行对比屠宰实验,分别测定并计算其体尺指标(体长、体高、胸围)、体尺指数(体型指数、胸围指数、体躯指数)和胴体等级分割肉质量,即一级肉(后腿肉和腰肉)、二级肉(肋肉和肩颈肉)、三级肉(腹下肉),确定巴美肉羊在生长发育和胴体等级肉产量方面是否具有优越性。结果表明:巴美肉羊的胸围、胸围指数和体躯指数均显著大于同月龄小尾寒羊和苏尼特羊(P<0.05),且随着月龄增加,该类指标的增加速率也快于对照组肉羊。同时,6、8月龄巴美肉羊的各等级肉质量均显著大于同月龄对照组肉羊(P<0.05),且随着月龄增加,其优质肉块的增长速率也大于其他肉块。因此,巴美肉羊与小尾寒羊和苏尼特羊相比,具有良好的前躯和躯干相对发育能力以及该品种肉羊良好的优质肉块的产肉性能。

基于屠宰性能探讨不同生长阶段肉鸭饲粮棉籽粕的适宜水平

本试验先后进行2次试验研究饲粮棉籽粕水平对不同生长阶段肉鸭屠宰性能的影响,并进一步根据屠宰性能探讨肉鸭饲粮棉籽粕的适宜水平。试验1、2均采用单因素试验设计,试验1饲粮棉籽粕水平分别为0、8.28%、16.56%、24.83%、33.11%；试验2饲粮棉籽粕水平分别为0、5.83%、11.60%、17.50%、23.30%。试验1肉鸭1～21日龄采食试验饲粮,22～35日龄采食无棉籽粕的玉米-豆粕型饲粮；试验2肉鸭1～14日龄采食无棉籽粕饲粮,15～35日龄采食试验饲粮。35日龄时每个试验的每个重复屠宰1只肉鸭测定其屠宰性能。结果表明：1）在试验1中,随饲粮棉籽粕水平的增加,肉鸭半净膛率与全净膛率线性增加（ P＜0.05）,16.56%棉籽粕组肉鸭腹脂重和腹脂率显著低于其他各组（ P＜0.05）。2）在试验2中,随饲粮棉籽粕水平的增加,饲粮棉籽粕水平线性或二次影响肉鸭活体重、半净膛重、全净膛重和胸肌重（ P＜0.05）,二次影响肉鸭的屠体重（ P＜0.05）,23.30%棉籽粕组肉鸭活体重、半净膛重、全净膛重、胸肌重及胸肌率显著低于其他各组（P＜0.05）。3）基于不同的屠宰指标肉鸭饲粮棉籽粕适宜水平为7.51%～14.78%。以上结果提示,在以可消化氨基酸平衡模式配制饲粮时,1～21日龄肉鸭采食棉籽粕高达33.11%饲粮,22～35日龄采食玉米-豆粕型饲粮对35日龄屠宰性能无显著影响；结合35日龄屠宰性能来考虑,15～35日龄肉鸭饲粮棉籽粕水平不宜超过14.78%。

务川黑牛不同杂交组合屠宰性能及肉质研究

实验旨在了解安格斯牛、利木赞牛和西门塔尔牛与务川黑牛杂交一代的产肉性能和肉品质。随机选取24月龄安务F1、利务F1、西务F1和务川黑牛公牛各3头,测定其屠宰性能和肉品质指标。结果表明:3种牛对务川黑牛杂交改良效果显著(P<0.05),屠宰率、肉骨比以利务F1牛最高,胴体重、净肉重、净肉率以安务F1牛最高,眼肌面积以西务F1牛最高;利务F1牛的熟肉率最高,安务F1牛的剪切力最低,肉色L45min、a45min、b45min值以西务F1牛色泽最亮,安务F1牛肉粗脂肪含量显著低于务川黑牛,利务F1牛肉与务川黑牛肉大理石纹都为3级,安务F1和西务F1牛肉大理石纹则为2级;系水力、滴水损失、水分、蛋白质、pH在不同杂交组合之间差异不显著。综合产肉性能和肉品质考虑,建议选择利木赞牛和安格斯牛作为务川黑牛杂交改良的父本进行推广。

关新杂交驴部分体尺和产肉性能测定

对8岁新疆驴和关×新F1(关中驴×新疆驴)进行了产肉性能测定,结果表明,在相同的饲养环境条件下,关×新F1驴与新疆驴相比,F1公驴的体高、体重和胴体重分别提高了16.44%、35.02%和39.52%,杂交优势极显著(P<0.01);F1母驴体高、体重和胴体重分别提高了18.01%、30.44%和38.23%(P<0.01)。

影响猪里脊肉出品率因素的研究

对影响烤猪里脊肉出品率的有关因素进行了研究,结果表明盐水注射率为40%、滚揉时间为11h、干燥温度为65℃、干燥时间为30min、蒸煮温度为82℃、蒸煮时间为40min时可确保烤猪里脊肉在感官质量,其出品率为126%。

船舶摇摆和工艺参数对南极磷虾挤压脱壳效果的影响

为了探究风浪造成的船只摇摆和工艺参数设置对南极磷虾挤压脱壳加工效果的影响,该文测量记录了不同横摇和纵摇状态下脱壳加工的得肉率和虾壳残留,分析了不同条件下脱壳滚轴长度区域的脱壳完成率。结果表明:船舶摇摆会对脱壳加工得肉率与虾壳残留率造成影响,但差异均不显著(P>0.05),在纵摇7?和横摇5?时虾壳残留率分别达到1.07%和1.64%。船舶的摇摆对脱壳完成率有一定影响,随着摇摆幅度的增加,同一区域内脱壳完成率呈下降趋势。增加滚轴的长度能有效防止由于摇摆幅度增加而造成脱壳完成率降低的问题,当滚轴长度为1 200 mm时,脱壳完成率大于95%。放置时间对脱壳效果的影响较大(P<0.05),放置2 h后的磷虾在区域Ⅳ的脱壳完成率降低至94%,虾壳残留率也相应增多。研究结果可为南极磷虾脱壳设备的应用和产业化提供参考。

机器视觉预测牛肉产量级研究现状及展望

介绍国外传统牛肉产量级评估方法,论述国内外机器视觉预测牛肉产量级的研究进展,并指出我国机器视觉牛肉产量级研究面临的问题以及发展方向。

生猪肉产量预测的非接触实时在线机器视觉系统

为了准确估测生猪肉产量,该文提出了一种自动提取生猪活体特征的方法,建立了生猪肉产量预测算法。首先,基于自主研发的生猪肉产量预测的机器视觉系统装置实时采集54头活体大白猪的俯视图和侧视图,然后根据图像处理技术对所得的图像进行分析,提取生猪的体长、胸宽、臀宽、体高等体尺参数值;同时通过称量装置获得每头猪的活体质量。其次,将54头生猪样品按2∶1的比例分为校正集和验证集,基于体长、胸宽、臀宽、体高和体质量5个特征参数分别利用多元线性回归法(multiple linear regression,MLR)和偏最小二乘回归法(partial least-squares regression,PLSR)建立不同的肉产量预测模型,通过比较各预测模型的估测精度、相关系数等,确定最佳预测模型。分析结果表明,5个参数中体质量对肉产量预测的权重最大;偏最小二乘回归方法的预测结果较好,最佳预测模型的预测相关系数为0.95,预测误差为3.09 kg。试验结果证实,在检测系统中使用基于生猪的体尺参数和体质量建立的偏最小二乘回归预测模型可快速准确预测生猪肉产量,适于实际生产应用。

加权马尔可夫链理论在肉类产量预测中的应用

为准确反映肉类产量的波动特征,基于加权马尔可夫链理论提出了灰色残差修正模型,采用均值-均方差分级法,将残差灰拟合精度指标划分为4个状态,利用加权马尔可夫链理论对残差预测值进行修正。以1994—2011年郑州市肉类产量为基础,建立预测模型进行实证分析,并在模型中加入等维信息,结果表明,与传统的灰色预测相比,预测平均相对误差由21.88%降低为1.312%,较好地提高了预测精度。