莱芜猪胴体品质肉质特性及其随体重变化规律的研究

研究测定了25头莱芜猪的胴体品质和肉质特性,分析了莱芜猪胴体、肌肉品质随体重(35、40、50、60、70、80、90kg)的变化规律,为确定不同生长阶段的适宜营养水平和上市屠宰体重提供依据。结果表明,莱芜猪自35~90kg瘦肉率在42.43%~55.29%之间,肌肉pH值稳定在6.19~6.52之间,肉色指标优良,大理石纹评分在2.50~4.38之间,肌内脂肪含量在4.51%~19.92%之间;当70kg体重屠宰时,肌肉失水率较低为13.47%,肉色、大理石纹评分较高分别为3.5、3.38,肌内脂肪含量较高为11.54%。胴体和肉质性状间相关程度有强有弱,相关系数有正有负。相同性状间有较强的正相关,相反性状间有较强的负相关。综合分析试验结果认为,莱芜猪以体重70kg作为上市屠宰体重比较合理。     

不同体重商品猪胴体性能肉质性状及其相关程度研究

研究测定了92～109 kg体重阶段31头杂交商品猪的胴体品质和肉质特性，以分析商品猪胴体、肌肉品质随体重的变化规律及其相关程度，为确定适宜上市屠宰体重提供依据。结果表明，商品猪在92～95 kg阶段屠宰瘦肉率最高为61.17％，分别比其它3组提高4.83％（P>0.05）、11.83％（P<0.05）和8.84％（P<0.05）；在107～109 kg阶段屠宰肉品质〖JP2〗优良，肌肉pH 6.07，肉色和大理石纹评分较高分别为3.13和 3.33，肌内脂肪含量较高为3.89％，肌肉失水率较低为18.91％。胴体和肉质性状间相关程度有强有弱，相关系数有正有负。相同性状间有较强的正相关，相反性状间有较强的负相关。综合分析试验结果认为，注重产肉量强调胴体瘦肉率时可选择在92～95 kg阶段屠宰；注重肉品质时可选择107～109 kg阶段屠宰；若二者兼顾则选择95~98 kg阶段屠宰较为合适。     

The Effect of Gender on Slaughtering Performance and Meat Quality in Sunite Sheep

The purpose of this experiment was to study the effect of gender on the slaughter performance and meat quality of Sunite sheep.Twelve 6-month-old Sunite rams and ewes at the same body condition were selected from the grazing herds of the Sunite Zuoqi Improvement Station Breeding Farm to determine their slaughter performance and meat quality.The slaughter test results showed that the bone quality and bone-meat ratio of the rams were significantly higher than that of the ewes (P<0.05),and the net meat quality and net meat rate of the ewes were significantly higher than that of the rams (P<0.05).The results of meat quality traits showed that the drip loss of ewes were significantly lower than that of rams (P<0.05),and the other indicators were not significantly different (P>0.05).The results of conventional nutrient composition of muscles showed that the intramuscular moisture content of the rams were significantly higher than that of the ewes (P<0.05),and the intramuscular fat content of the ewes were significantly higher than that of the rams (P<0.05),while the other indicators were not significantly different (P>0.05).The results of amino acid determination showed that the essential amino acid ratio in muscle of sunite ewes were significantly higher than that of rams (P<0.05),but there was no significant difference between the rams and ewes that formed the precursor amino acid content of meat flavor (P>0.05).Fatty acid measurement results showed that the saturated fatty acid ratio in the subcutaneous fat of rams was significantly lower than that of ewes (P<0.05).There was no significant difference in the ratio of saturated fatty acids in muscle fat and tail fat (P>0.05);The ratio of monounsaturated fatty acids in ewes tail fat was significantly higher than that of rams (P<0.05).The ratio of monounsaturated fatty acids in subcutaneous fat and intermuscular fat was not significantly different between rams and ewes (P>0.05).The ratio of polyunsaturated fatty acids in intermuscular fat of rams was significantly higher than that of ewes (P<0.05),and there was no significant difference in the content of polyunsaturated fatty acids in subcutaneous fat and tail fat (P>0.05).In summary,it showed that gender had a certain influence on the slaughter performance and meat quality of 6-month-old Sunite sheep.     

Effect of Supplementing Alfalfa Powder to Diet on Growth Performance and Meat Quality of Goose

The experiment was aimed to investigate the effects of dietary alfalfa powder on the growth performance,body size,slaughter performance,organ index and meat quality of Siji geese.A total of 256 15-day-old geese (half male and half female) with similar body weight were randomly divided into four groups with 4 replicates of 16 geese each.The geese in control group were fed with corn-soybean meal-based diet (control diet),and geese in the experimental groups were fed the basal diet replaced with 10%,20% and 30% alfalfa powder,respectively.The results showed that,compared with the control group,dietary alfalfa powder supplementation had no significant effect on the average daily intake,average daily gain,feed conversion ratio,body oblique length,keel length,shin circumference,semi diving length,chest width and shin length (P>0.05),and also had no effect on the carcass ratio,half-eviscerated carcass ratio and pectoral muscle ratio (P>0.05).However,dietary 20% and 30% alfalfa powder supplementation significantly increased the chest depth (P<0.05),dietary 30% alfalfa powder significantly decreased the full-eviscerated carcass ratio (P<0.05),and dietary 10% alfalfa powder significantly increased the leg muscle ratio (P<0.05) of geese.In addition,dietary alfalfa powder significantly decreased the abdominal fat ratio (P<0.05),raised the growth index of liver,jejunum,ileum,and cecum (P<0.05),and increased the water loss rate of pectoral muscle and leg muscle (P<0.05) compared with the control group.Dietary 10% and 30% alfalfa powder significantly increased duodenal growth index (P<0.05) of geese.In conclusion,dietary alfalfa powder supplementation might improve the slaughter performance (increase chest depth and leg muscle ratio,reduce abdominal fat rate) and organ growth index (increase the growth index of liver,duodenum,jejunum,ileum and cecum).However,dietary alfalfa powder increased water loss rates in pectoral muscle and leg muscle,and 30% alfalfa powder reduced the full-eviscerated carcass ratio of geese.The appropriate supplementation level of alfalfa powder was recommended at 10% in the present study.     

Effects of Lactobacillus and Bacillus subtilis Mixed Fermentation Feed on Growth Performance,Slaughter Performance and Intestinal Morphology of Broilers

The purpose of this experiment was to study the usage and proportion of fermented feed in broiler feed.By adding 0,10% and 20% fermented complete formula feed to the broiler feed,and granulating normally,the influence of the usage mode of the fermented feed on the production performance,slaughter performance,intestinal tract and other related indexes of the broiler feed were studied,so as to provide reference for the application of the fermented feed in the broiler feed.180 1-day-old healthy AA male broilers were randomly divided into 3 groups with 6 replicates in each group and 10 chickens in each replicate.The three treatment groups were fed with 0,10% and 20% of the total fermented feed for 42 days.The results showed that:From the whole period (1-42 days old),the 10% fermentation feed substitution group significantly reduced the feed consumption and weight gain ratio (P<0.05),and the average daily weight gain increased (P=0.05).At 42 days old,there was no significant effect of fermented feed on slaughter performance (P>0.05).The ileal crypt depth of broilers in the 20% fermentation feed replacement group was significantly higher than that in the control group and the 10% replacement group (P<0.05).The length of duodenal villi and V/C in 20% and 10% fermentative feed substitution group was significantly higher than that in control group (P<0.05).The results showed that the replacement of 10% fermented feed in broiler feed could reduce the ratio of feed to weight gain,increase the average daily gain,and have a certain impact on intestinal development.     

白耳黄鸡生产性能和肉质性状的研究

对白耳黄鸡生长性能、屠宰性能、常规肉质、胸腿肌化学成分、肌肉组织学特性、胸肌氨基酸和脂肪酸含量等指标进行了研究。白耳黄鸡公母鸡的屠宰率、胸肌率、腿肌率、蛋白质含量、氨基酸总量、腹脂率、人体必需氨基酸含量、必需脂肪酸含量等分别为89.23/90.18%,16.65/18.09%,22.37/21.91%,23.64/25.30%,206.29/218.8mg/g,1.64/2.39%,92.78/96.75mg/g,30.69/29.52%。结果表明,白耳黄鸡的各指标都表现优良,其具有屠宰性能好,肉质优良,必需氨基酸和脂肪酸含量高,腹脂率低等特点,是一个值得推广的地方优良品种。     

萧山草三黄鸡屠宰性能和肉质分析

研究对70日龄萧山草三黄鸡进行了屠宰性能和肉质性状的测定,结果显示:公鸡活重、屠体重、半净膛率和全净膛率优于母鸡,差异显著(P<0.05)。腿肌的肉色OD值、剪切力和pH值均大于胸肌,系水力小于胸肌,差异均显著(P<0.05);水分含量、粗脂肪含量大于胸肌,粗蛋白含量、粗灰分含量小于胸肌,差异均显著(P<0.05)。研究表明母鸡的肉质优于公鸡,屠宰性能则不及公鸡。     

秦川肉牛新品系的培育

产于陕西八百里秦川的秦川牛,千百年来一直是关中农业生产的主要动力和粪肥来源,建国后,通过广大科技工作者的通力合作,协同攻关,运用国际育种先进技术,选出优秀公牛,授配主产区大批秦川母牛,配合其他措施,从而加速了秦川牛的选育,使之很快由役用型转变为肉用型,形成了秦川肉牛新品系。经屠宰测定,其肉用,役用性能不仅大大高于５０年代调查时测定的指标,而且其中一些肉用性能指标与国际著名的肉牛品种相比也毫不逊色,     

低磷饲粮中超量添加植酸酶对肉鸡生长性能、屠宰性能、消化器官指数、养分表观利用率及胫骨指标的影响

本试验旨在研究低磷饲粮中超量添加植酸酶对肉鸡生长性能、屠宰性能、消化器官指数、养分表观利用率及胫骨指标的影响。选取1日龄罗斯308商品肉仔鸡公雏2 160只,随机分为5组,每组12个重复,每个重复36只。正对照组(PC组)饲喂基础饲粮,负对照组(NC组)饲喂低磷饲粮(钙和有效磷水平均比PC组降低0.15%),试验组在低磷饲粮的基础上分别添加500(NC500)、1 500(NC1500)和4 500 FTU/kg(NC4500)的植酸酶。试验期39 d。结果表明:1)NC和NC500组14、25和38日龄体重以及1~14日龄、15~25日龄和1~38日龄平均日增重(ADG)、平均日采食量(ADFI)、育肥指数显著低于PC组(P<0.05)。除NC4500组1~38日龄ADFI显著高于PC组(P<0.05)外,NC1500和NC4500组38日龄体重以及1~38日龄ADG、ADFI、育肥指数与PC组差异不显著(P>0.05)。2) NC组钙表观利用率显著低于PC组(P<0.05),NC500、NC1500和NC4500组日均排钙量显著低于PC组(P<0.05)。NC500、NC1500和NC4500组磷表观利用率显著高于NC和PC组(P<0.05),日均排磷量显著低于NC和PC组(P<0.05)。3)NC组胫骨强度显著低于其他各组(P<0.05),NC4500组胫骨强度显著高于其他各组(P<0.05)。4) NC组26、39日龄肝脏指数显著高于PC组(P<0.05),NC1500和NC4500组26日龄空肠、回肠指数显著低于PC和NC组(P<0.05),NC1500和NC4500组39日龄肝脏、胰腺、十二指肠、空肠指数显著低于NC组(P<0.05)。5) NC组全净膛率、腿率均显著低于PC组(P<0.05),NC1500和NC4500组全净膛率显著高于NC组(P <0.05),NC500、NC1500和NC4500组腿率显著高于NC组(P<0.05)。6)与PC组相比,NC1500、NC4500组每只鸡收益分别增加了0.61、0.49元。由此可见,本试验条件下,低磷饲粮中超量添加植酸酶能改善肉鸡生长性能、屠宰性能,提高钙、磷利用率及胫骨强度,提高经济效益,其中植酸酶适宜添加量为4 500 FTU/kg。     

Surface deterioration of wood-flour polypropylene composites by weathering trials

The market for wood-fiber plastic composites (WPCs) is expanding rapidly in many countries including Japan, where WPCs are mainly used for exterior products. In such applications, WPCs undergo undesirable color change, chalking, and shrinkage and swelling, and accordingly there is a need to better understand the mechanisms responsible for the weathering of WPC and develop methods of improving their weathering resistance. In this study, weatherability of WPC was assessed by natural and accelerated weathering trials. Discoloration (whitening) of WPC during exposure was caused by degradation of both wood and plastic. Darker color pigments as additives improved the color stability of WPC; however, chalking on the surfaces still occurred. The color stability of WPC was improved by application of exterior coatings. Preweathering of WPC (before coatings were applied) increased the absorption of coatings by the WPC and had a positive effect on the color stability and prevented chalking of the composites. Parts of this study were presented at the IUFRO XXII World Congress Meeting, Brisbane, August 2005 and the IAWPS 2005, Yokohama, November 2005