热应激条件下,垫料中油和抗菌剂喷雾液对饲养在树叶和玉米芯垫料上肉鸡生产性能的影响

本研究的方向是调查在热应激条件下,抗菌剂溶液、油和它们的敷用物表面的喷雾液体对饲养在树叶和玉米芯垫料物质上的肉鸡生产性能的影响效果。在一个周边开放部分控制的鸡舍内将670羽5日龄的strighrunArian肉鸡随机分为45栏(0.09m2/羽)。三种垫料物质即木刨花(WS)、地玉米芯(GCC)(长1.5cm)和树叶,在它们表面上添加油喷雾液(0.4L/m2动物食物型的葵花油)、抗菌剂溶体(3%)和两者的混合处理液。生产性能特征、胸部和脚趾损伤以及垫料特征,三者的数据都被集合在一定的阶乘整理下分析。56日龄的体重、14日龄的采食量、28日龄的垫料湿度、14日龄的垫料pH值和14日龄与56日龄的垫料温度,它们受垫料类型的影响显著(P<0.05)。28、42和56日龄的体重、29～42日龄之间和1～42日龄之间的采食量、56日龄以上的死亡率、28和56日龄的垫料温度和垫料pH值,垫料处理对它们有明显的影响。树叶和地玉米芯表明对改变肉鸡的垫料物质有好的潜力。抗菌剂溶体、油和两者敷用物的表面喷雾液都不是增强鸡的健康和生产性能的有效物质。肉鸡的增长和整齐度被认为是达到结果的首要指标。     

热应激条件下，垫料中油和抗菌剂喷雾液对饲养在树叶和玉米芯垫料上肉鸡生产性能的影响

本研究的方向是调查在热应激条件下,抗菌剂溶体、油和它们的敷用物表面的喷雾液体对饲养在树叶和玉米芯垫料物质上的肉鸡生产性能的影响效果。在一个周边开放部分控制的鸡舍内将670羽5日龄的strighrunArian肉鸡随机分为45栏(0.09平方米/羽)。三种垫料物质即木刨花(WS)、地玉米芯(GCC)(长1.5厘米)和树叶,在它们表面上添加油喷雾液(0.4升/平方米动物食物型的葵花油)、抗菌剂溶体(3%)和两者的混合处理液。生产性能特征、胸部和脚趾损伤以及垫料特征,三者的数据都被集合在一定的阶乘整理下分析。56日龄的体重、14日龄的采食量、28日龄的垫料湿度、14日龄的垫料PH值和14日龄与56日龄的垫料温度,它们受垫料类型的影响显著(p<0.05)。28、42和56日龄的体重、29-42日龄之间和1-42日龄之间的采食量、56日龄以上的死亡率、28和56日龄的垫料温度和垫料PH值,垫料处理对它们有明显的影响。树叶和地玉米芯表明对改变肉鸡的垫料物质有好的潜力。抗菌剂溶体、油和两者敷用物的表面喷雾液都不是增强鸡的健康和生产性能的有效物质。肉鸡的增长和整齐度被认为是达到结果的首要指标。     

复合益生菌喷雾制剂对肉鸡生产性能、免疫功能、鸡舍空气微生物及有害气体的影响

试验旨在研究复合益生菌喷雾制剂对肉鸡生长性能、免疫功能、鸡舍空气微生物及有害气体的影响。选取15 000只1日龄科宝肉鸡,随机分为2组,每组5个重复,每个重复1 500只。试验组喷洒10 mL/m²复合益生菌混合制剂,对照组喷洒相同剂量的清水。试验期42 d。结果显示:与对照组相比,鸡舍内喷洒复合益生菌喷雾制剂显著提高肉鸡1～21日龄和1～42日龄平均日增重(P<0.05),显著增加肉鸡胸腺指数、法氏囊指数(P<0.05),提高肉鸡血清中IgA和IgG含量(P<0.05);与对照组相比,肉鸡14日龄时,鸡舍空气中大肠杆菌数量显著降低(P<0.05),14日龄和35日龄时,鸡舍内乳酸杆菌数量显著增加(P<0.05);14日龄和35日龄时,鸡舍空气中氨气、硫化氢含量显著降低(P<0.05)。综上所述,鸡舍中喷洒复合益生菌喷雾制剂可以提高肉鸡生长性能、增强免疫功能,降低鸡舍大肠杆菌含量,促进乳酸杆菌增殖并改善鸡舍空气质量。     

不同饲养方式和饲养密度对肉鸡生长性能及肉品质的影响

本试验旨在研究不同饲养方式和饲养密度对肉鸡生长性能及肉品质的影响。试验采用3×2双因子试验设计,选用7日龄的Ross 308白羽肉鸡504只,3种饲养方式分别为地面厚垫料平养、笼养和网上平养,2个饲养密度分别为12(正常密度)和16只/m2(高密度),共6个组,每个组6个重复。试验期35 d。试验结果显示：1)饲养方式极显著影响7~28日龄和29~42日龄的平均日采食量、平均日增重及料重比( P<0.001)。7~28日龄,肉鸡平均日采食量为垫料平养>笼养>网上平养,平均日增重为垫料平养>网上平养>笼养,料重比为网上平养<垫料平养<笼养。29~42日龄,肉鸡平均日采食量垫料平养显著高于笼养和网上平养(P<0.05),平均日增重笼养显著高于垫料平养和网上平养( P<0.05),料重比笼养<网上平养<垫料平养。在7~28日龄,高饲养密度有降低平均日采食量的趋势(0.050.05)。在29~42日龄,高饲养密度则有提高平均日采食量的趋势(0.050.05),且垫料平养的高饲养密度肉鸡的腿肌pH1最低。综上所述,饲养方式和饲养密度都会影响肉鸡生长性能,但两者不存在交互作用;但在垫料平养和网上平养方式中提高饲养密度会对腿肌肉品质有显著影响。     

不同垫料对肉鸡生产性能的影响及垫料肥值的评价

168只7日龄阿拉伯Acros肉鸡饲养于4种类型的垫料(锯屑、稻谷壳、甘蔗渣和小麦秸)上至49日龄以比较不同垫料处理对肉鸡生产性能的影响、评价不同垫料的肥值和垫料球虫卵囊数量。锯屑、稻谷壳、甘蔗渣和小麦秸处理组间的活体重、饲料消耗、饲料转化率和存活率差异不显著(P>0.05)。但锯屑组的活体重和存活率高于其它组。甘蔗渣垫料的水分含量最高(P<0.05),其次分别是锯屑、稻谷壳和小麦秸。稻谷壳垫料的氮、磷、钾最高(P<0.01),其次分别是锯屑、甘蔗渣和小麦秸。所有处理组垫料的球虫卵囊含量在5周龄前突然升高,而后在7周龄时突然降低。在35日龄和42日龄时,不同垫料的卵囊含量差异不显著,但在49日龄时差异极显著(P<0.01)。结果表明,在孟加拉国的秋后期,从肉鸡生产性能考虑,锯屑是较合适的垫料,其次是稻谷壳、甘蔗渣和小麦秸。     

肉鸡舍垫料的选择及其时肉鸡生产的影响

随着肉鸡生产的迅猛发展,不少国家对如何选择理想的鸡舍垫料进行了研究。早在1968年,荷兰对鸡舍垫料进行的试验表明。理想的鸡舍垫料饲养出的肉鸡最为理想。选择肉鸡舍垫料,首先要考虑垫料的吸水性,以保持鸡舍地面干燥。一般来说,冬天鸡舍内垫料的湿度应保持在36%左右,夏天垫料混度应在18%左右.如果垫料湿度过大,则需要更换干燥的垫料,否则,过湿的垫料对肉鸡的生长发育不利,轻则使鸡羽沾染污泥,重则使肉鸡胸部出现水泡,附     

垫料不同加铺方法对白羽肉鸡脚垫皮炎的影响

以江苏沿海地区某大型养殖场地面平养的8栋鸡舍24万羽白羽肉鸡为研究对象,分别设计四种加铺垫料方法,选两栋鸡舍在进鸡前一次加铺完毕,饲养期间正常翻动垫料,其余鸡舍进鸡前加铺垫料3cm,饲养至21日龄,其中三栋鸡舍2d加铺一次,三栋鸡舍3d加铺一次,加铺厚度相同,在出栏前检查鸡只脚垫皮炎（FPD）情况。结果显示,鸡只PFD情况分批加铺垫料比进鸡前一次性铺完效果好,2d加铺一次比于3d加铺一次垫料的效果好。     

不同饲养密度对肉鸡舍内有害气体、粉尘和微生物的影响

试验旨在探讨饲养密度对黄羽肉鸡舍内有害气体、粉尘及微生物的影响.选用1 440只21日龄苏禽黄鸡(公雏),随机分成3个饲养密度组,即8只/m2组(低密度组,LSD)、16只/m2组(中密度组,MSD)、24只/m2组(高密度组,HSD),每组3个重复,共9间鸡舍,每间饲养面积均为10 m2.试验期为21 d.结果表明:HSD组42日龄肉鸡鸡舍内二氧化碳、氨气含量显著高于其他两组(P＜0.05);LSD组28日龄肉鸡鸡舍内粉尘含显著低于其他两组(P＜0.05);LSD组28、35、42日龄肉鸡鸡舍内空气中大肠杆菌的含量显著高于其他两组(P＜0.05),且LSD组42日龄肉鸡鸡舍垫料中大肠杆菌含量显著高于HSD (P＜0.05).由此可知,夏季适当降低饲养密度可以改善平养肉鸡舍中有害气体和粉尘状况,但对降低鸡舍中微生物含量效果不佳.     

研究表明家禽垫料燃烧灰分可用作肉鸡饲料Ca和P来源

正家禽生产中的鸡舍垫料通常作为废弃物或有机肥原料处理,近期美国奥本大学研究人员开展了一项研究,为家禽垫料用作饲料添加剂开辟了一个新途径。试验用不同水平(0、25%、50%、75%和100%)的家禽垫料灰分替代肉鸡日粮中磷酸氢钙以评估家禽垫料燃烧灰分用作饲料添加剂的作用效果,替代比例以二者重量换算。研究结果表明,100%的垫料灰分替代组与25%垫料灰分替代组相比,试验鸡21日龄体增重下降。而在整个试验周期结束后,即41日龄时,各组肉鸡体增重、饲料消耗和饲料转化率均无显著差异,并且100%垫料灰     

垫料厚度对鸡舍氨气、二氧化碳和粉尘的影响

本试验旨在探讨垫料厚度对黄羽肉鸡舍内氨气、二氧化碳和粉尘的影响。试验选用1 600只21日龄苏禽黄鸡(公雏),随机分成4组,每组5个重复,每个重复80只鸡,分别饲养在结构、空间一致的独立鸡舍内(共20间),饲养密度为8只/m2。各组锯屑垫料厚度依次为4、8、12、16 cm,试验期从22~70日龄。结果表明:不同厚度垫料对各日龄鸡舍中粉尘含量有显著影响(P0.05),12 cm和16 cm垫料组35日龄鸡舍中氨气含量显著低于其他两组(P0.05),而粉尘含量显著高于其他两组(P0.05),12 cm垫料组70日龄鸡舍中氨气含量显著低于其他三组(P0.05),二氧化碳含量显著低于4 cm垫料组(P0.05)。由此可知,适当增加垫料厚度能够降低鸡舍氨气和二氧化碳含量,综合本试验结果,12 cm厚度锯屑垫料效果最佳。     

葡萄上杀虫、杀菌剂登记和使用现状分析及建议

基于我国农药信息网数据和新修订的《食品安全国家标准 食品中农药最大残留限量》（GB 2763 — 2021）中葡萄相关指标,结合葡萄生产实际,对我国葡萄上农药登记的现状及生产中农药的应用情况进行梳理,指出了存在的问题,分析了产生问题的原因,提出了相应建议,以期为我国葡萄的安全生产提供参考。     

Effects of surgical sterilization on canine and feline health and on society

Surgical sterilization of dogs and cats is a well-accepted measure for population control in some countries, but is considered unethical as an elective surgery in other countries. This is a review of what is known regarding positive and negative effects of gonadectomy surgery on individual animals and on societal management of unowned dog and cat populations.     

Effect of lasalocid sodium and molasses on performance of fattening lambs and on rumen liquor and blood parameters

Two experiments were conducted to evaluate the effects of sugar beet molasses (0, 8 and 16%) with or without lasalocid sodium (33 ppm) on rumen liquor and blood parameters of sheep, and on fattening reared Karagouniko breed lambs. In Expt. 1 six adult Karagouniko fistulated wethers were fed six different pelleted diets. The results showed that lasalocid decreased (P less than 0.01) total VFAs concentration in the rumen (7.1%) by reducing (P less than 0.001) acetic, n-butyric and iso-valeric acids while increased (P less than 0.001) propionic acid concentrations. The same trends were observed in molar proportions of the individual VFAs. The total VFAs production was also depressed by 13.75% when molasses were used at the level of 16%. No interaction among the main treatments was observed with the exception of L X M with 16% molasses where the propionic acid concentration decreased, and those of butyric and iso-valeric acids increased. Lasalocid did not alter the mean values of rumen liquor pH and ammonia nitrogen concentration while molasses increased the later parameter. No significant differences on dietary protein degradability were observed among treatments. Lasalocid reduced the beta-HBA concentration by 13% in the blood while molasses increased it (P less than 0.001). Free fatty acids' concentration was decreased by the molasses inclusion to the diets, while lasalocid didn't alter blood glucose concentration. Finally, the number of protozoa in the rumen liquor was reduced by 49 and 70% at 0 and 5 hours post feeding respectively with the addition of lasalocid to the diets, regardless of the use of molasses. In Expt. 2 utilized 86 weaned male Karagouniko fattening lambs, with initial mean LW 13 kg, for 60 days. They were assigned to six groups and fed ad libitum with diets of the same composition as in Exp 1. Lasalocid increased the growth rate by 8.6%, reduced feed consumption by 4.8% (P less than 0.005) and improved feed conversion by 11.8%. Molasses also improved growth rate by 16-34% and increased feed consumption by 15-22%. The interaction of L X M to feed consumption was significant (P less than 0.001). None of the treatments had an effect on carcass characteristics. Finally lasalocid showed its positive action when it was used in combination with molasses in ruminants' diets.     

Effect of egg composition on hatchability and on growth and slaughter characteristics of meat-type chicks

1.?Using the so-called TOBEC (Total Body Electrical Conductivity) method, which allows the determination of egg composition in vivo, correlations between egg composition, hatchability and hatched chicks’ development were studied.

2.?A total of 1500 hen eggs (Ross-308) were measured by TOBEC, and eggs with extremely high (10%, n = 150), extremely low (10%, n = 150) and average (10%, n = 150) electrical conductivity values were chosen for further investigation.

3.?During the incubation period, it was observed that eggs with high electrical conductivity had a significantly higher mortality than eggs with low electrical conductivity.

4.?It was observed that both the increase in electrical conductivity at the same egg weight, and the increase in egg weight at the same electrical conductivity resulted in an increase in the hatching weight.

5.?It was found that the dry matter, protein and fat content of the chicks hatched from eggs with low electrical conductivity was higher at hatching than that of the chicks hatched from eggs with high electrical conductivity.

6.?At 42 d of age the liveweight of cocks and pullets hatched from eggs with low electrical conductivity was 3·2 and 8·2% higher than the liveweight of cocks and pullets hatched from eggs with high electrical conductivity.

7.?Because of the higher liveweight at slaughter, there was a significant superiority of the chicks hatched from eggs with low electrical conductivity in the case of the examined carcase traits at slaughter.

8.?Similar tendencies were found also in the ratios of carcase variables to liveweight, but the between group differences were not statistically significant in this case.

9.?Based on the results it was concluded that TOBEC seems to be a useful method for separating eggs with different composition.

10.?This could be a good starting point for further in vivo investigations in order to clarify the effect of egg composition on hatchability and further development.     

Effect of diet on composition of cecal contents and on excretion and composition of soft and hard feces of rabbits

A total of 260 New Zealand White growing rabbits were used to study the effect of diet on chemical composition of cecal contents and on production and composition of soft and hard feces. Eight diets varying in their acid detergent fiber (9.8% to 32.7%) and starch (13% to 30%) levels were evaluated. The diet affected (P less than .01) all the variables studied, except dry matter (DM) and molar proportions of volatile fatty acids on cecal contents. An increase of dietary crude fiber increased crude fiber level in cecal contents (from 11.58% to 26.53%). However, a relatively lower proportion of fibrous material was found in the cecal contents when rabbits were fed the more fibrous diets. This suggests that dietary fiber has a direct influence on the efficiency of particle separation in the digestive tract. Crude protein and volatile fatty acid concentrations of cecal contents decreased (from 30.14% to 19.65% and from 47.8 to 36.7 mmol/liter, respectively) when dietary crude fiber increased. This could be related to availability of energy to cecal microorganisms. Ammonia concentration of cecal contents was not affected by dietary crude fiber. Daily production of soft feces varied from 14.98 to 29.59 g DM/d, and the contribution of soft feces to total DM and to crude protein intake ranged from 10.6% to 15.0% and from 12.8% to 20.5%, respectively; these values were the smallest and the largest for the least and the most fibrous diets, respectively. From this study we conclude that dietary fiber has a major effect on the digestive processes in the rabbit and that dietary starch level has no influence on any of the variables studied.     

血根碱药理及毒理作用的研究进展

血根碱(sanguinarine)作为一种苯菲啶异喹啉类生物碱,具有抗菌、抗炎、抗氧化、抗肿瘤、改善肝功能及诱导细胞凋亡等作用,同时对肝脏、心脏等具有一定的毒性。作者就血根碱对细菌、真菌和癌细胞的药理作用及毒性作一综述,为该药在临床中的有效合理应用奠定基础。     

冷、热应激对水禽的影响及营养调控研究进展

应激可通过神经-体液相关激素的基因和蛋白质、肠道微生物群、脂质氧化等,影响水禽的生理状态和生产性能,导致经济损失.水禽常见的应激包括热应激和冷应激.生产上可以通过控制环境温度、在饲粮中添加营养物质缓解水禽冷、热应激.文章以鸭、鹅为水禽代表,对冬、夏季节水禽生产中面临的冷、热应激主要的影响机制及营养调控措施进行综述,旨在...     

硅藻土共固定化淀粉酶和糖化酶的研究

以糖化酶和α-淀粉酶为双酶体系、硅藻土为载体,用吸附法同时固定了这两种酶,得到的最适的共固定化条件为硅藻土(g):糖化酶(U):淀粉酶(U)=1:100:160,pH值4.5～5.0,温度5～15℃左右,缓冲液为柠檬酸缓冲液。共固定化酶的性质为:最适pH值为5.0;最适温度为55℃;米氏常数Km=16.830mg/ml;最大反应速率Vmax=1.500mg(/ml·min),其稳定性良好。