猪屠宰前何时停料好

屠宰前停料对猪肉安全和品质的影响已被广泛研究。许多研究证明，屠宰前12～18h，停料对上市屠宰用猪有积极的影响。本文总结了猪屠宰前停料的有利方面和不利之处。     

浅谈肉羊快速育肥技术

肉羊育肥生产实际是在短的时间内，以最低的生产成本获得量多质好的羊肉。根据绵羊屠宰年龄不同，通常将羊肉分成大羊肉和羔羊肉两种。大羊肉指周岁以上脱换过门齿以后的羊肉；羔羊肉指生后不满周岁，还是乳齿的羊肉，其生后4～6个月屠宰的羔羊。羊的肥育主要是为了在短时间内，用低廉的成本，获得品质好、数量多的羊肉。     

獭兔皮的粗加工技术

獭兔皮的粗加工技术四川省草原研究所（６１１４３０）范成强蒲翔陈琳四川省家畜繁育改良总站关云秀１适时屠宰掌握屠宰獭兔的最佳时间，主要取决于宰杀年龄，并要避开换毛期，这是保证毛皮质量的关键。獭兔换毛分年龄性换毛和季节性换毛。獭兔年龄性换毛有二次，第一次在...     

短杂西杂与泾源黄牛屠宰试验

短杂西杂与泾源黄牛屠宰试验宁夏泾源县为全国养牛基地县之一。近几年各类杂种牛育肥出栏量激增，短角杂种和西门塔尔杂种牛与泾源黄牛相比，产肉能力提高幅度缺乏科学依据，为此于１９９３年１０月进行各类牛只的屠宰对比试验。在农户中选购年龄相近、平均３．４岁，健康...     

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。     

屠宰肥肝鹅的方法

肥肝鹅与普通肉用鹅不同，不能确定统一的屠宰时间。有的鹅耐填程度差，到一定时间，就会表现出消化不良，瘫软在地，甚至突然死亡的现象。因此，对鹅要注意观察，及时屠宰，否则放血不及时肝脏就会淤血，降低肥肝的质量。     

优质高档牛肉规模化生产技术

高档牛肉是指能加工成高档食品的优质牛肉,如牛排、烤牛肉、肥牛肉等.优质牛肉产自屠宰年龄在12～18月龄的公牛,屠宰体重在400～500 ㎏;高档牛肉产自屠宰年龄为36月龄以内的阉牛,屠宰体重在600 ㎏左右.     

川西北高原型藏山羊适宜屠宰期的研究

对德格县马尼干戈区的高原型藏山羊不同季节，年龄进行了屠宰对比试验、肉的品质分析、板皮测定、计算牧草报酬。结果表明高原型藏山羊作肉用的适宜屠宰期为暖季末，１０－１２月龄为宜。     

乳鸽屠宰技术

乳鸽屠宰技术＠尹文乳鸽屠宰技术尹文乳鸽生产已成为近代养殖业的一个重要组成部分，不少国家和地区已把乳鸽作为优质肉类的来源之一。乳鸽屠宰的日龄最好在２５～３０天。根据羽毛的生长情况，可以看出乳鸽的年龄。未满２０日龄的乳鸽头部长满尖细的乳毛，背上和翅膀的羽毛还未...     

年龄对无角陶赛特羊×小尾寒羊F2羔羊屠宰性能的影响

试验旨在探讨年龄对优质陶赛特羊与小尾寒羊杂交二代横交固定后母羔(陶寒F2)屠宰性能的影响.选取同等饲养条件下的3月龄和4月龄陶寒F2各6只,研究其屠宰性能.结果表明:4月龄羔羊的宰前活重、胴体重分别比3月龄高38.34％和50.47 ％(P＜0.01),4月龄羔羊的屠宰性能高于3月龄.随着年龄的增长,血液、毛皮、心、肝、肾、其他内脏(肺、脾、肠系膜)、消化道(瘤胃、网胃、瓣胃、皱胃、小肠、大肠)等其他一些屠宰指标呈现累积生长的变化规律.因此,陶寒F2母羔的屠宰性能明显受年龄的影响.     

不同炮制的茜草对家兔凝血的影响

研究茜草不同炮制方法对家免凝血、凝血酶原时间的影响.选取1.5～2.0 kg健康家兔24只,雌雄不分,随机分成2组,每组12只.第1组静注生茜草水煎醇沉液,第2组静注炒茜草水煎醇沉液,剂量均为1g/kg,给药前及给药后30 min,心脏采血,用试管法分别测定两组家兔凝血时间及凝血酶原时间.结果表明,静注生、炒茜草水煎醇沉液均有促进凝血和缩短凝血酶原时间的作用,用药前后差异极显著(P＜0.01),且生茜草优于炒茜草,但差异不显著(P＞0.05).     

光照时间突变对鸡群生产性能的影响

选择产蛋性能稳定的鸡群为试验对象，对其突然延长或突然缩短光照时间，次日与每天光照16h的鸡群的生产性能进行比较。试验表明，无论是光照时间的突然延长还是突然缩短都会对蛋鸡生产性能产生明显的负面影响，因此，在产蛋鸡管理过程中应注意保持光照时间的恒定。     

Analyses of hemorrhagic diathesis in high-iron diet-fed rats

Iron overload has been well recognized to cause oxidant-mediated cellular/tissue injury; however, little is known about the effects of iron overload on the blood coagulation system. We encountered an unexpected bleeding tendency in rats fed a high-iron diet in a set of studies using iron-modified diets. In this study, we investigated the mechanism of hemorrhagic diathesis induced by dietary iron overload in rats. Six-week-old F344/DuCrlCrlj male rats were fed a standard (containing 0.02% iron) or a high-iron diet (containing 1% iron) for 6 weeks and were then sampled for hematological, blood biochemical, coagulation, and pathological examinations. Serum and liver iron levels increased in rats fed the high-iron diet (Fe group) and serum transferrin was almost saturated with iron. However, serum transaminase levels did not increase. Moreover, plasma prothrombin time and activated partial thromboplastin time were significantly prolonged, regardless of the presence of hemorrhage. The activity of clotting factors II and VII (vitamin K-dependent coagulation factors) decreased significantly, whereas that of factor VIII was unaltered. Blood platelet levels were not influenced by dietary iron overload, suggesting that the bleeding tendency in iron-overloaded rats is caused by secondary hemostasis impairment. In addition, hemorrhage was observed in multiple organs in rats fed diets containing more than 0.8% iron. Our results suggest that iron overload can increase the susceptibility of coagulation abnormalities caused by latent vitamin K insufficiency.     

中国美利奴绵羊肉用品系生长轴相关基因表达对其十二指肠发育的影响

本文旨在探讨生长轴基因与羔羊十二指肠生长发育的关系。分别于0、7、14、30、60和90日龄随机选取健康的中国美利奴绵羊(新疆军垦型)肉用品系雌、雄各3只,测定体质量后屠宰,迅速采集其脑垂体、肝脏和十二指肠等组织样品,并测量十二指肠长度。用荧光实时定量PCR法分别测定脑垂体中生长激素(GH)和生长激素释放激素受体(GHRHR),肝脏和十二指肠中生长激素受体(GHR)、胰岛素样生长因子1(IGF-1)和胰岛素样生长因子1受体(IGF-1R)基因表达的发育性变化,并进行了性别间比较。结果表明,羔羊肝脏中GHR基因和十二指肠中GHR、IGF-1基因表达mRNA丰度的变化模式与垂体中GH和GHRHR基因表达mRNA丰度的变化发育模式相似,呈先升高后逐渐下降的趋势,但这种趋势有一定的时差性;十二指肠的日增长发育性变化模式与肝脏中IGF-1基因表达的变化模式相似。结果提示,十二指肠的发育性变化主要受到肝脏中产生的IGF-1内分泌作用的调控,同时也可能受到脑垂体中GH内分泌的直接作用。     

Determination of gastrointestinal passage rate using three different markers in laying hens

The titanium dioxide (TiO₂) marker technique is currently widely practiced as a method to evaluate gastrointestinal (GI) passage rate in poultry. However, this method requires sacrificing the animal to obtain digesta samples, is labour‐intensive and eliminates the possibility of follow‐up studies with the same individual. The aim of this study was to evaluate whether the radiographic methods barium‐impregnated polyethylene spheres (BIPS) and barium sulphate (BaSO₄) suspension are in agreement with the TiO₂ technique and can be used as an alternative method for GI passage rate determination in laying hens. Whole‐body radiographs were taken at different time points. Hens of group 3 (n = 55) were orally inoculated with 5 g of feed mixed with 0.15 g TiO₂, 5 hens per time point sacrificed, and whole gastrointestinal organs (crop, proventriculus, gizzard, small intestine and large intestine) were collected and analysed for TiO₂ content. The average marker passage rate of hens administered BaSO₄ was significantly faster than those administered BIPS (gizzard: 15.2 hr vs. 43.2 hr; small intestine: 15.2 hr vs. 38.4 hr, respectively). A greater percentage of BIPS remained in the crop at 0, 0.5, 2, 3 and 8 hr post‐inoculation (p.i.) and in the gizzard at 2, 24, 36 and 48 hr p.i. (all p < 0.05) compared to TiO₂. In conclusion, the evaluation of the GI transit time is feasible using BIPS, TiO₂ and BaSO₄. The evaluation of the GI transit time using BIPS and BaSO₄ needs further investigation.     

Training-induced changes in clotting parameters of athletic horses

The purpose of this study was to investigate the effects of training on prothrombin time, activated partial thromboplastin time, and fibrinogen (Fb) concentrations in horses to assess potential adaptive response to training. Fifteen clinically healthy horses were enrolled in the present study and equally divided into three groups. Group A completed an intense training program, group B participated in a light training program, and group C included sedentary horses. After 5 weeks, group B was subjected to the same training program completed by group A and renamed group B1. Blood samples were collected by jugular venipuncture from each animal at rest and analyzed within 2 h after sampling. A two-way ANOVA for repeated measures showed a significant effect of training (p < 0.05) on Fb concentrations in group B1 alone during the first week after changing the training program. Our findings demonstrated that Fb is a parameter susceptible to training. Fb plasma levels increase with a more intense training program. However, Fb plasma levels decreased after the first week and returned to basel levels, suggesting that the horses had adapted to the new training program.     

Effect of storage conditions on prothrombin time, activated partial thromboplastin time and fibrinogen concentration on canine plasma samples

The present study was to assess the effect of storage conditions on prothrombin time (PT), activated partial thromboplastin time (aPTT) and fibrinogen concentration in blood samples of healthy dogs. Thirty-five dogs of various breeds were included in the study. Citrated blood samples were obtained and plasma was divided into four aliquots to assess selected clotting parameters by means of a coagulometer. The first aliquot was analysed within 1 h after collection, while the remaining 3 were stored at 8℃ for 4, 8 and 24 h, respectively. One-way repeated measures analysis of variance documented a significant decreasing effect on PT at 24 h compared to 8 h and on fibrinogen concentration after 8 and 24 h compared to sampling time and at 4 and 24 h compared to 8 h post sampling. In conclusion, the results of this study indicate that only fibrinogen appears prone to significant decrease. In fact, aPTT is not substantially affected by refrigeration for at least 24 h post sampling and PT showed a statistical difference that does not necessary indicate biological significance as the results obtained were within reference intervals for the dog.     

Effect of silage chop length on feed intake and feeding behaviour of finishing feedlot steers

This study determined the effects of silage chop length (20?mm; long or 10?mm; short) and diurnal time on feeding behaviour of 80 feedlots steers. Feed intake and feeding behaviour of each steer in each pen were measured continuously from 0:00 to 12:00?h (AM) and from 12:00 to 24:00?h (PM). Chop length had no effect on feed intake or the growth performance of steers, but longer chop length increased the duration of feeding and reduced the rate of intake. Head down time and head down time per feeding activities were greater during the PM than AM. There was a chop length?×?diurnal time interaction for feeding frequency with the number of bunk visits being greater in the PM than AM for both diets. Feeding activities were 50% higher during the PM than AM when steers were fed either long- or short-chopped silage diets twice daily.     

晾晒时间和青贮时间对青贮玉米发酵品质的影响

目的 探究不同晾晒时间和青贮时间对全株青贮玉米发酵品质的影响。方法 以玉米（Zea mays L.）青贮品种“曲辰9号”为试验材料,将乳熟末期的青贮玉米全株收获粉碎后,在阴凉处分别晾晒0（对照,CK）、1、2、3、4 d,然后在塑料桶（5 L）中分别进行青贮,待青贮60、90、120 d时进行发酵品质的评定。结果 青贮玉米的含水量随着晾晒时间的增加而降低,在晾晒2、3、4 d后含水量显著（P<0.05）低于CK;用晾晒2、3、4 d的全株青贮玉米原料进行青贮,pH值显著（P<0.05）高于CK,晾晒2 d青贮120 d处理除外。晾晒时间对乳酸、丁酸、中性洗涤纤维（NDF）和酸性洗涤纤维（ADF）含量均产生显著（P<0.05）影响,青贮时间仅对乳酸、丁酸产生显著（P<0.05）影响,其中,乳酸含量随着青贮时间的延长而增加,丁酸含量在原料晾晒之后明显增加。CK处理中,青贮90、120 d的NDF含量显著（P<0.05）高于青贮60 d处理。利用氨态氮、乙酸、丙酸、丁酸开展V-Score分析,晾晒导致青贮玉米发酵品质降低,试验中品质较优的青贮为原料粉碎后未经晾晒的处理（CK）。结论 在未经晾晒处理下进行青贮60 d的青贮玉米,综合品质较高。在青贮玉米原料含水量为74%时,不建议粉碎之后通过晾晒降低含水量再青贮。