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[前沿资讯 ] 欧盟评估一种内切-1,3（4）-β-葡聚糖酶作为育肥鸡和断奶仔猪饲料添加剂的安全性和有效性 进入全文
食品伙伴网
2023年1月11日，据欧盟食品安全局（EFSA）消息，应欧盟委员会要求，欧盟动物饲料添加剂和产品（FEEDAP）研究小组就一种内切-1,3（4）-β-葡聚糖酶（endo-1,3(4)-beta-glucanase）作为育肥鸡和断奶仔猪饲料添加剂的安全性和有效性发表科学意见。据了解，该添加剂中是由斐济曲霉CBS 589.94生产的。经过评估，专家小组认为在建议的使用条件下该添加剂对育肥鸡和断奶仔猪是安全的。该添加剂作为一种动物技术添加剂，在10 FBG/千克饲料的最低推荐水平下，对育肥鸡和断奶仔猪是有效的。部分原文报道如下：Following a request from the European Commission, the EFSA Panel on Additives and Products or Substances used in Animal Feed (FEEDAP) was asked to deliver a scientific opinion on the safety and efficacy of endo-1,3(4)-beta-glucanase produced by Aspergillus fijiensis CBS 589.94 (RONOZYME® VP (CT/L)) as a zootechnical feed additive for chickens for fattening and weaned piglets. based on the no observed adverse effect level identified in a subchronic oral toxicity study in rats and the tolerance trials provided, the additive was considered safe for chickens for fattening and weaned piglets at the proposed conditions of use. The Panel also concluded that the use of the product as a feed additive does not rise concerns for consumers and the environment. Owing to the lack of data obtained with the final formulations, the Panel could not conclude on the potential of the additive to be irritant to skin and eyes or on its potential as a dermal sensitiser. Due to the proteinaceous nature of the active substance, the additive is considered a respiratory sensitiser. The Panel concluded that the additive is efficacious as a zootechnical additive in chickens for fattening and weaned piglets at the minimum recommended level of 10 FBG/kg feed.
[学术文献 ] Probiotic, Paraprobiotic, and Hydrolyzed Yeast Mixture Supplementation Has Comparable Effects to Zinc Oxide in Improving Growth Performance and Ameliorating Post-weaning Diarrhea in Weaned Piglets 进入全文
中国知网
A total of 150 21-day-old weaned piglets [(Yorkshire × Landrace) × Duroc] were randomly assigned to 3 groups (CON, TRT1, TRT2) to evaluate the effects of dietary supplementation of probiotic, paraprobiotic, and hydrolyzed yeast mixture (PPY) on growth performance, nutrient digestibility, fecal bacterial counts, fecal calprotectin contents, and diarrhea rate in a 42-day experiment (phase 1: days 1-14; phase 2: days 15-42). There were 10 replicate pens per treatment with 5 pigs per pen (three gilts and two barrows). Pigs in CON were only provided with a basal diet. Pigs in TRT1 were provided with a basal diet + 3000 mg/kg zinc oxide during phase 1 and a basal diet during phase 2. Pigs in TRT2 were provided with a basal diet + 200 mg/kg probiotic (Saccharomyces cerevisiae boulardii) + 800 mg/kg paraprobiotic (inactivated yeast strains of Saccharomyces cerevisiae and Cyberlindnera jadinii) + 10 g/kg hydrolyzed yeast mixture during phase 1, and a basal diet + 100 mg/kg probiotic + 400 mg/kg paraprobiotic mixture during phase 2. Pigs in TRT1 and TRT2 were significantly heavier at day 14 and 42 than CON pigs. Growth rate during days 1-14, 15-42, and 1-42 and feed efficiency during days 1-14 were similarly affected by treatment while feed efficiency was significantly higher for TRT2 pigs between 15-42 and 1-42 days. Moreover, nitrogen and energy digestibility in both TRT1 and TRT2 were higher than that in CON. During experimental periods, diarrhea rate in TRT1 and TRT2 was lower than that in CON. Therefore, we demonstrated that PPY supplementation had comparable effects as ZnO in improving growth performance and nutrient digestibility as well as ameliorating post-weaning diarrhea in weaned piglets.
[学术文献 ] Multiple amino acid supplementations to reduce dietary protein for pigs during early and late finisher periods under commercial conditions 进入全文
中国知网
BACKGROUND：With the easy availability and competitive prices of crystalline amino acids (AA), a further reduction of dietary crude protein (CP) would be possible. Two experiments were conducted to assess the growth efficiency of early and late finishing pigs fed with protein-restricted diets supplemented with Lys, Met, Thr, Trp, Val, Ile and His under practical conditions. In Exp. 1, a total of 840 early finishing pigs were allocated to 4 dietary treatments with CP levels designed at 150, 142, 134, and 126 g kg-1 diet. In Exp. 2, a total of 768 late finishing pigs were allotted to 4 dietary treatments providing CP levels at 140, 130, 120, and 110 g kg-1 diet. RESULTS：In Exp. 1, data showed that CP levels could be decreased from 150 to 126 g kg-1 without adversely affecting performance of early finishing pigs as no significant difference was observed for final bodyweight, average daily gain (ADG), feed to gain ratio (F:G), or average daily feed intake (ADFI). In Exp. 2, late finishing pigs consuming 120 g kg-1 CP tended to have the highest ADG and lowest F:G while those fed the 110 g kg-1 CP diet showed the opposite trend. Based on quadratic analysis, the optimum CP levels to maximize ADG and minimize F:G were 126 and 127 g kg-1 , respectively. CONCLUSION：These findings showed that dietary CP levels can be decreased to 126 g kg-1 for early finishing pigs while improved performance was noted in late finishing pigs consuming 120 g kg-1 CP. This article is protected by copyright. All rights reserved.
[学术文献 ] 发酵豆粕对断奶仔猪生长性能、消化酶及肠道菌群结构的影响 进入全文
中国知网
【目的】本试验旨在探讨发酵豆粕（FSBM）对断奶仔猪生长性能、消化酶活性及肠道菌群结构的影响。【方法】试验选取48头21日龄断奶仔猪（杜×长×大,6.88 kg±0.13 kg）,随机分为对照组和试验组,每组4个重复,每个重复6头猪。对照组饲粮为基础饲粮,试验饲粮用6%FSBM等量替代基础饲粮中的豆粕。试验期为20 d。试验期间记录采食量和体重。试验第21天,每个重复选取2头猪屠宰,收集回肠食糜测定消化酶活性和肠道菌群结构,并对两者进行相关性分析。【结果】（1）饲喂FSBM可显著提高断奶仔猪的终末体重和平均日增重（average daily gain,ADG）,并显著降低了料重比（feed/gain,F/G）（P＜0.05）;（2）FSBM组断奶仔猪回肠中的胰蛋白酶和淀粉酶活性显著提高（P＜0.05）;（3）饲喂FSBM显著提高了断奶仔猪回肠食糜中拟杆菌门、普雷沃氏菌科NK3B31类群、厌氧弧菌属、瘤胃菌科UCG-005、普氏菌属2、巨型球菌属、副杆菌属、Solobacterium及毛螺菌科UCG-004的相对丰度,显著降低了链球菌属的相对丰度（P＜0.05）;（4）相关性分析显示,胰蛋白酶活性与颤螺菌属、瘤胃菌科UCG-005的相对丰度呈显著正相关（P＜0.05）,而与Subdoligranulum、萨特氏菌属的相对丰度呈显著负相关（P＜0.05）;淀粉酶活性与普雷沃氏菌科UCG003、柔嫩梭菌属的相对丰度呈显著正相关（P＜0.05）,而与琥珀酸弧菌属、罗姆布茨菌属的相对丰度呈显著负相关（P＜0.05）;脂肪酶活性与柠檬酸杆菌属的相对丰度呈显著负相关（P＜0.05）。【结论】饲喂FSBM可改变断奶仔猪回肠菌群结构,增加断奶仔猪回肠胰蛋白酶和淀粉酶活性,并提高其生长性能。
[前沿资讯 ] 2022年生猪市场形势回顾与2023年展望 进入全文
国际畜牧网
2022年猪肉产量预计增幅较明显，市场情绪影响出栏节奏。从国内生产来看，预计全年猪肉产量较上年增5.9%，供给量预计较上年增1.9%。总体来看，市场情绪对三季度和四季度出栏节奏影响显着，导致供给出现明显后置的特征。从不同季度来看，一季度同比增幅较大。从不同月份屠宰量来看，3-4月份同比激增超过50%，5月份开始环比下降，7月份同比下降，11月份环比明显增长，同比降幅明显收窄，预计12月份或同比略高于上年同期。猪肉进口明显下降。从猪肉进口来看，预计全年进口175万吨，同比下降52.8%。2022年1-11月份猪肉进口155.8万吨，同比下降56%。主要来自西班牙、巴西、丹麦、美国、加拿大，分别占进口总量的26.9%、24.2%、10.8%、7.2%和6.2%，合计75.4%。总体来看，上半年进口低位，下半年缓慢恢复。猪杂碎进口99.9万吨，同比下降16.1%，预计全年进口109万吨左右。消费需求受影响显着。2022年上半年消费处于淡季，消费下降而供给增加；三季度供给下降叠加消费短期提振，带动猪价持续反弹；四季度中后期猪肉价格较高叠加疫情又导致短期消费低迷。总体来看，无论家庭消费、餐饮消费和加工消费均呈现部分时间低迷的特征，对短期猪价产生明显影响。2022年生猪均价较上年小幅下跌，存在超涨和超跌现象。2022年生猪和猪肉均价分别为19.01元/公斤和30.70元/公斤，分别同比下跌7.2%和7.7%。总体来看，如果养殖户生产经营没有受到疫病影响，自繁自养养殖户2022年为第4年连续的盈利期，平均1头盈利约300元，较上年小幅下降。
[学术文献 ] 基于响应面法的仔猪配奶罐搅拌器数值模拟与优化 进入全文
中国知网
为了探究仔猪配奶罐中搅拌器参数对奶水搅拌效果的影响，设计了一种双层桨叶仔猪配奶罐，采用CFD数值模拟与响应面分析相结合方法，以转速、层间距、桨叶角度和离底距离为设计优化参数，以搅拌功率、混合时间和平均温升速率为响应指标，设计四因素三水平正交仿真试验，建立响应指标的回归模型，得到双层桨叶搅拌器的最优参数值。结果显示：转速和桨叶角度对搅拌功率的影响极显著，转速、层间距、桨叶角度和离底距离对混合时间影响极显著，转速对平均温升速率影响极显著，层间距和桨叶角度对平均温升速率影响显著，其中转速对搅拌器性能影响最大；响应面回归模型具有较好的拟合性，通过响应面回归模型得到最优的参数组合为转速80 r/min、层间距170 mm、桨叶角度30°、离底距离100 mm。与优化前相比，搅拌功率减小27.08%，混合时间减小70.15%，平均温升速率提升9.57%，且湍流动能云图分布和温度云图分布明显优于初选模型。
