不同切割酸度对奶豆腐品质影响研究

研究不同切割酸度对奶豆腐品质的影响,以确定其最佳切割酸度。采用单因素试验设计,切割酸度分别为45°T～50°T、55°T～60°T、65°T～70°T、75°T～80°T、85°T～90°T。在其他工艺条件相同的情况下,分别加工一批奶豆腐,然后测定奶豆腐的性能指标。结果表明,随着切割酸度的增加,奶豆腐的感官评定值先增加,然后逐渐降低;奶豆腐的pH4.6可溶性氮含量、质量分数12%TCA可溶性氮和游离氨基酸总量都逐渐增加;而pH值和水分含量逐渐降低。以感官评定值为主指标,结合其他性能指标,确定切割酸度为65°T～70°T。     

兽药生产过程中导致产品不符合质量标准的问题分析

从质量标准的角度,论述了兽药生产企业在生产过程中,导致产品不符合质量标准的几种问题,并对这些问题进行了分析,意在引起企业的注意,减少不合格产品。     

乙酸镁对氟烷基因杂合子育肥猪肌肉加工品质的影响

育肥猪屠宰前饲粮中短期添加乙酸镁,研究其对氟烷基因杂合子育肥猪肌肉加工品质的影响。选用体重相近的氟烷基因杂合子(HalNHaln)大长猪(大白猪×长白猪)36头随机分为2组,即对照组、乙酸镁组,每组18头。乙酸镁组在屠宰前5 d,基础日粮中添加镁1 500mg/kg(以乙酸镁形式),对照组饲喂基础日粮。试验表明:在猪屠宰前饲粮中短期添加1 500 mg/kg水平的镁对试验猪的平均日采食量没有明显影响(P>0.05);可以显著降低肌肉的滴水损失(P<0.05),提高猪肉的熟肉率,从而提高猪肉的加工品质。     

在语文教学中如何培养学生的“创新精神”？

创新是一个民族进步的灵魂,是国家兴旺发达的不竭动力源泉。因此,对创新人才的培养,应该从基础教育抓起。为了在语文教学中培养学生的“创新精神”,教师首先应转变观念,使自己成为有创新精神的人。其次为学生创设和谐、民主的学习氛围,让学生最大限度地发展创造性思维能力。应让学生丰富知识、夯实基础、拓展视野,为创新思维的发展打下坚实的基础。     

The effect of life history events on carcass merit and price of cull dairy cows

Cull dairy cows contribute almost 10% of national beef production in the United States. However, different factors throughout the life of dairy cows affect their weight and overall body condition as well as carcass traits, and consequently affect their market price. Therefore, the objectives of this study were: (1) to assess relationships between price ratio and carcass merit of cull dairy cows sold through several sites of an auction market and (2) to investigate the effect of animal life history events and live weight on sale barn price (BP) and price ratio (as a measure of relative price), as an indicator of carcass merit. Data from 4 dairy operations included 3,602 cull dairy cow records during the period of 2015 to 2019. Life history events data were collected from each dairy operation through Dairy Comp software; live weight and price were obtained periodically from the auction market, and the carcass data were provided by a local packing plant. Cow price in dollars per unit of live weight ($/cwt) and price ratio were the 2 outcome variables used in the analyses. Price ratio was created aiming to remove seasonality effects from BP (BP divided by the national average price for its respective month and year of sale). The association between price ratio and carcass merit traits was investigated using canonical correlation analysis, and the effect of life history events on both BP and price ratio was inferred using a multiple linear regression technique. More than 70% of the cows were culled in the first 3 lactations, with an average live weight of 701.5 kg, carcass weight of 325 kg, and dressing percentage of 46.3%. On average, cull cows were sold at $57.0/cwt during the period considered. The canonical correlation between price ratio and carcass merit traits was 0.76, indicating that price ratio reflected carcass merit of cull cows. Later lactations led to lower BP compared with cows culled during the first 2 lactations. Injury, and leg and feet problems negatively affected BP. Productive variables demonstrated that the greater milk production might lead to lower cow prices. A large variation between farms was also noted. In conclusion, price ratio was a good indicator of carcass merit of cull cows, and life history events significantly affected sale BP and carcass merit of cull cows sold through auction markets.     

骆驼乳研究进展

本文介绍了骆驼乳的营养和生物学价值,影响骆驼乳品质的因素,以及骆驼乳掺假鉴定技术,展望了骆驼乳的开发前景,以期为骆驼乳的研究提供理论依据.     

Growth performance and carcass quality are not different between pigs fed diets containing cold-fermented low-oil DDGS and pigs fed conventional DDGS,but pelleting improves gain to feed ratio regardless of source of DDGS

The objective of this study was to test the hypothesis that growth performance and carcass characteristics of pigs fed diets containing cold-fermented, low oil distillers dried grains with solubles (DDGS) is not different from that of pigs fed diets containing conventional DDGS regardless of the physical form of the diets. A total of 160 barrows and gilts were used. There were 4 diets, 10 pens per diet, and 4 pigs per pen. Pigs were weaned at 21 d of age and fed a common phase 1 diet that did not contain DDGS during the initial 7 d post-weaning. Pigs were then allotted to the four diets that were arranged in a 2 × 2 factorial design with two sources of DDGS (cold-fermented and conventional DDGS) and two diet forms (meal and pellets). Pigs were fed phase 2 diets from day 7 to 21 and phase 3 diets from day 21 to 43 post-weaning. All diets were based on corn and soybean meal, but phase 2 diets also contained 15% DDGS and phase 3 diets contained 30% DDGS. From day 43, pigs were fed grower diets for 38 d, early finisher diets for 38 d, and late finisher diets for 18 d and these diets also contained 30% DDGS. Feed was provided on an ad libitum basis and daily feed allotments were recorded. Pigs were weighed at the beginning of each phase and at the conclusion of the experiment. On the last day of the experiment, the pig in each pen with a body weight that was closest to the pen average was slaughtered and carcass measurements were determined. Combined results for the two nursery phases indicated that feeding meal diets instead of pelleted diets increased (P < 0.001) average daily feed intake and decreased (P < 0.05) gain to feed ratio (G:F). However, no differences between the two sources of DDGS were observed for the overall growth performance of weanling pigs. For the entire growing-finishing period, the source of DDGS did not affect growth performance, but pigs fed meal diets had reduced (P < 0.001) G:F compared with pigs fed the pelleted diets. There were no differences between the two sources of DDGS for carcass characteristics. Back fat was greater (P < 0.05) for pigs fed pelleted diets than for pigs fed meal diets. In conclusion, no differences in growth performance or carcass characteristics between pigs fed cold-fermented DDGS and pigs fed conventional DDGS were observed. However, pigs fed pelleted diets had greater G:F and greater back fat than pigs fed meal diets.     

口蹄疫悬浮灭活疫苗质量控制措施

结合几年来的口蹄疫生产质量管理实践,对质量控制的意义及质量控制的保证措施（原辅料、工艺、检验等方面对质量控制措施）等方面进行了综述和探讨,为建立科学合理的质量控制措施,保证产品质量提供参考.     

山西省三种饲草作物种植模式的效益分析

为分析山西省玉米（Zea may）连作（CC）、玉米+苜蓿（Medicago sativa）+燕麦（Avena sativa）轮作（C-A-O）和玉米+小黑麦（Secale sylvestre）轮作（C-T）3种种植模式的经济效益和营养品质,在山西省不同地区进行了实地调研,对轮作过程进行全程监测并分析农作物的营养品质。结果表明,C-T一年平均经济效益最高,CC次之,C-A-O最低。但在3种不同种植模式下C-A-O的营养品质显著高于其余2种种植模式（P<0.01）,CC连作最低。综合来看,C-A-O综合效益较高,C-T综合效益次之,CC综合效益最低。