肉鸡脂肪性状调控基因的研究进展

随着人们生活水平的提高，对优质肉鸡肉质提出了更高要求。适量的皮下脂肪可改善胴体外观，但皮下脂肪和腹脂太多则不好；而较高含量的肌内脂肪（IMF）能改善肉品质。近年来，从DNA水平上研究家禽肉质的报道相对较少，但随着人们消费水平的提高，改善肉质已成为养殖业面临的首要问题。因此，肉质的研究成为动物遗传学者研究的热点。为此，本文把对影响肉鸡肉质脂肪性状主要基因的研究状况做一论述，为今后培育低脂肪优良肉鸡品种的育种工作奠定基础。     

维生素A限饲对伊比利亚猪肌内脂肪脂肪细胞的分化和脂肪酸组成的影响

研究的目的是探讨日粮维生素A水平是否与伊比利亚猪生长前期(活重35.8 kg)和育成期(活重158 kg)脂肪细胞分化或脂肪积累差异有关。选取活重16.3 kg的伊比利亚猪分配到两个日粮组,一组饲喂添加维生素A 10 000 U·kg-1的日粮(对照组);另一组不添加维生素A(VAR)。试验结果表明,维生素A的水平对猪生长性能和胴体品质没有影响。维生素A的早期限饲在生长早期极显著增加了背最长肌(LT)前脂肪细胞数量(P<0.001);并且增加育成期中性脂质含量,改善了其组成(较高的单不饱和脂肪酸和较低的饱和脂肪酸含量,P<0.05)。维生素A的限饲增加仔猪脂肪生成潜力,且不影响胴体性状。     

脂肪营养及其在猪生产中的应用

猪日粮中添加脂肪在国内外已有二十几年的历史,各国专家都进行了较多的研究,在妊娠后期日粮和泌乳期日粮中添加脂肪会提高乳量、初乳和常乳的乳脂率以及仔猪从出生到断奶的生存率。国内专家们在这方面也得出了相同的结果。脂肪是体组织的主要成分,而且脂肪由于其生物学价值和能量价值高在猪的营养中起着重要作用,是猪饲粮中的重要组成成分。脂肪在动     

Estimated Breeding Value in Iranian Buffaloes

This study was conducted from 1992-2002 on 65,534 individual milk records and fat percentage in 473 herds, in six provinces of Khuzestan, Mazndaran, W. Azerbaijan, E. Azerbaijan, Ardabil and Gilan. The data was analyzed by SAS sotfware using GLM procedure. The heritability and breeding value of 1,195 animals were calculated by DFRML procedure. The average milk yield per lactation, days of lactation, fat percentage and LSM of fat percentage were 1,513 kg, 202 days, 5.04 and 6.77, respectively. The estimated heritability of milk was 0.16. The LSM of average milk production in the provinces of Gilan, Mazandaran, E. Azerbaijan, W. Azerbaijan, Khuzestan and Ardabil were： 1,452, 1,586, 1,382, 1,183, 2,135 and 1,189 kg, respectively. These results indicated that Khuzestan province has the highest potential in the field of milk production. The top five highest breeding value bulls have been introduced to artificial insemination＇s station in the city of Uremia.     

过瘤胃脂肪对林麝体重和日粮表观消化率的影响

选用20头年龄相近,体况良好的成年雄性林麝。采用完全随机设计分为4组,研究日粮添加过瘤胃脂肪(0,5,10,15 g/d)对林麝体重和日粮表观消化率的影响。结果表明:日粮添加不同水平过瘤胃脂肪对林麝体重无显著影响(P0.05)。对林麝日粮粗蛋白、有机物、中性洗涤纤维、酸性洗涤纤维、钙、磷和干物质的表观消化率没有显著影响(P0.05);10 g/d组日粮粗脂肪和能量的表观消化率较对照组显著提高(P0.05),但与5 g/d组和15 g/d组差异不显著(P0.05)。结果显示,林麝日粮过瘤胃脂肪的适宜添加水平为10 g/d。     

Effects of Medium-chain Triglyceride on Growth Performance and Serum Biochemical Indices in Broilers

The study was conducted to investigate the effects of medium-chain triglyceride replacing the soybean oil in the basal diet on growth performance and serum biochemical indices of broilers.One hundred and forty four healthy,similar body weights AA broilers at the age of 14 days were randomly assigned to four groups with six replicates ger group and six broilers per replicate.Groups A,B,C and D were respectively fed with 0,0.6%,1.2% and 2% medium-chain triglyceride substituted the equivalent amount of soybean oil (using corn flour to balance the energy levels in each group) .The test lasted for 28 days and the indexes were measured once every two weeks.The results showed that the average daily gain and average daily feed intake of groups B,C and D were higher than that of group A,and the F/G was lower than group A.The average daily gain of groups C and D at 28 to 42 days old and group D at 14 to 42 days old were significantly higher than that of group A (P < 0.05).The serum glucose,total content of amino acid,total protein and albumin of groups B,C and D at age of 28 and 42 days old were higher than that of group A,while the serum triglyceride,total cholesterol and urea nitrogen levels were lower.The total cholesterol content at 42 days old and triglyceride concentrations at 28 days old of group C were significantly lower than those of group A (P < 0.05).The results indicated that medium-chain triglyceride could raise average daily gain and reduce the total cholesterol content and triglyceride concentrations of broilers,which were useful for improving the growth performance.     

一语惊人

正找老公的标准:带的出去,带的回来!其实人的长相就分为两大类:一类是天生丽质;一类是天生励志。这个年头找到真爱的机率和被雷劈的机率差不多。你以为你是谁?你就是泼出去的水,我连盆都不要。人之初,性本善,你掏钱,我吃饭。我不但手气好,脚气也不错。脂肪那么厚,动一下都那么难受。打遍天下所有的酱油,让别人吃醋去吧。和你擦肩而过你却不知道是我,因为我把头扭过去了。脸乃身外之物,可要可不要;钱乃必要之物,不得不要。     

硫酸对过氧化氢-乙酸预处理巨龙竹酶解和发酵的影响

以巨龙竹(DS)为研究对象，对其进行过氧化氢-乙酸(PA)预处理，探讨预处理中硫酸添加量对竹材化学组成、酶解效率和乙醇产率的影响。研究结果表明：随着预处理过程中硫酸用量的增加，竹材中的木质素质量分数不断降低，而纤维素和半纤维素的质量分数有所增加。在预处理中，添加硫酸作为反应助剂，能够使酶解效率提升，当硫酸体积分数为0.5%时，72 h的葡萄糖和木糖得率分别为84.77%和85.05%,与未添加硫酸的过氧化氢-乙酸预处理的巨龙竹相比，分别增加了42.40%和33.72%;其水解液经酵母发酵后的乙醇质量浓度为13.52 g/L,比未添加硫酸的过氧化氢-乙酸预处理水解液增加了73.33%。在巨龙竹过氧化氢-乙酸预处理过程中以硫酸作为助剂，能够降低底物的疏水性和表面木质素覆盖率，增加结晶度和比表面积，添加0.5%硫酸，纤维素酶可及度从未添加硫酸时的282.15 mg/g增加到500.12 mg/g,进而增加了纤维素酶与纤维素之间的生产性吸附，因此使巨龙竹的酶解效率和发酵产率得到提升。     

SZC-101型脂肪测定仪测定花生粗脂肪方法优化研究

用SZC-101型脂肪测定仪测定花生粗脂肪时,通常采用称量铝杯质量差的常规方法算出花生粗脂肪含量,1个铝杯只能测1个样品,效率太低。而采用称量放在滤纸筒里的独立小滤纸包的方法计算花生粗脂肪含量,1个滤纸筒里可以放3~4个独立小滤纸包。分析效率是常规方法的3~4倍,且测定结果与常规方法一致,建议推广使用。     

蛋鸡脂肪肝出血性综合征的诊断与防治

1临床及剖检变化 脂肪肝病鸡群一般表现为产蛋率上升慢,没有产蛋高峰期的出现。一般产蛋率上升到85%左右时就会开始下降。鸡只精神状态良好,有时不表现任何临床症状而突然死亡。死亡的鸡只表现为鸡冠、肉髯苍白,且一般体重偏大。