28～56日龄湘黄鸡真可消化钙需要量的研究

在研究了28-56日龄黄鸡的真可消化钙需要量。采用单因子试验设计,将400只健康1日龄的黄鸡随机分成5个处理组,每个处理5个重复,每个重复16只鸡。以磷酸氢钙和石粉为真可消化钙的来源,分别设置了0.28%、0.38%、0.48%、0.58%和0.68%五个真可消化钙水平,进行了为期28d的养殖试验。结果表明,随着钙水平的增加,采食量和日增重有显著下降的趋势,料肉比则为先减少后增加的趋势。湘黄鸡的真可消化钙需要量,当分别以生长性能、最大胫骨灰份和最大胫骨折断力为评定指标时,分别为：0.38%,0.41%和0.45%。     

Research on the Antioxident Function of Sulforaphane on the Leydig Cells of Cadmium Exposured Mice

The study was aimed to explore the antioxident function of sulforaphane (SFN) on the leydig cells of cadmium (Cd) exposured mice.Cd and SFN were added to the cell culture medium of TM3 cell, half inhibitory concentration (IC₅₀) of Cd and SFN safe dose range were determined.The tested model was set up,and the relative survival rate of TM3 cells, lactate dehydrogenase (LDH) activity and cell antioxidant levels were determined to study the antioxident function of SFN to cadmium exposured mice.The results showed that:①With the increase of Cd concentration,the relative survival rate of TM3 cells was decreased,and the IC₅₀ of Cd was 51.4 μmol/L;Within a certain concentration range,SFN could increased the cells survive rate,but there was toxicity when the SFN concentration was more than the scope,and the greater the concentration,the greater the toxicity. At experimental condition,SFN safety concentration were 2.5,5 and 10 μmol/L.②Compared with the control group,the GSH content,the T-SOD and GSH-Px activities in Cd group were significantly or extremely significantly decreased (P < 0.05;P < 0.01),and the LDH activity,the MDA content were increased.Additionally,the LDH activity and MDA content of SFN groups were decreased,while others three indexes were increased. Compared with Cd group,the GSH content,the T-SOD and GSH-Px activities of Cd+SFN groups were significantly or extremely significantly increased (P < 0.05;P < 0.01),however,the LDH activity,MDA content were decreased. The result indicated that SFN had the antagonism effect on toxicity of Cd in TM3 cell.     

基于动物福利视角的规模化奶牛养殖场经济效应分析

本研究遵循动物福利"5F"原则,结合150家规模化奶牛养殖场实地调研数据,构建奶牛场动物福利评价体系,测度动物福利水平,并进一步建立嵌入动物福利水平测度值的规模化奶牛养殖场收入函数,验证关联效应.结果表明:生理福利和环境福利是影响我国规模化奶牛养殖场动物福利的最重要的2个维度,受访的规模化奶牛养殖场生理福利和环境福利的...     

2018年进口奶牛检疫情况分析

随着十多年的超速发展,我国奶牛业已由单一品种的散养方式逐步转变为高产品种的规模化、集约化养殖方式。然而,我国奶牛整体遗传素质不高,多为进口高产奶牛与地方奶牛的低代次改良品种,以致原奶质量参差不齐,严重制约了我国奶业的健康发展。因此,大规模引进高品质的奶牛品种,已成为我国优化奶牛基因、推动畜牧业产业化发展的重要抓手,但同时也为检疫工作带来了挑战。本文通过分析2018年我国进口奶牛数量、来源国、疫病检出、进境口岸及隔离检疫场分布等数据,结合各来源国的疫病防控特点,有针对性地提出检疫要点,为我国全面提升进口奶牛的检疫水平、切实做好奶牛群体遗传改良计划、加快推进畜牧业转型升级提供参考。     

高温条件下复合抗应激剂对肉鸡的影响

本文研究了高温条件下复合抗应激剂对肉鸡的影响。结果表明：经历３２ ℃一周的５ ～８ 周龄肉鸡采食量、增重、饲料转化率均显著下降（Ｐ＜ ０ ．０１） ,饮服复合抗应激剂显著改善增重和饲料转化率（Ｐ＜ ０ ．０１） , 采食量未见明显改变,饲料转化率达到常温水平。３２ ℃１６ 小时血浆皮质酮、Ｔ３ 显著下降（Ｐ＜ ０ ．０１） 、Ｔ４ 显著升高（Ｐ＜ ０ ．０１） ;３２ ℃１２０ 小时血浆皮质酮、Ｔ３ 升高并超出常温组（Ｐ＜ ０ ．０５） 、Ｔ４ 较１６ 小时下降但仍高出常温组（Ｐ＜ ０ ．０５） 。饮服复合抗应激剂时血浆皮质酮、Ｔ３ 、Ｔ４ 显现相同变化规律,但这种变化得到显著缓解     

Bats adjust temporal parameters of echolocation pulses but not those of communication calls in response to traffic noise

Many studies based on acute short‐term noise exposure have demonstrated that animals can adjust their vocalizations in response to ambient noise. However, the effects of chronic noise over a relatively long time scale of multiple days remain largely unclear. Bats rely mainly on acoustic signals for perception of environmental and social communication. Nearly all previous studies on noise‐induced vocal adjustments have focused on echolocation pulse sounds. Relatively little is known regarding the effects of noise on social communication calls. Here, we examined the dynamic changes in the temporal parameters of echolocation and communication vocalizations of Vespertilio sinensis when exposed to traffic noise over multiple days. We found that the bats started to modify their echolocation vocalizations on the fourth day of noise exposure, with an increase of 42–91% in the total number of pulse sequences per day. Under noisy conditions, the number of pulses within a pulse sequence decreased by an average of 17.2%, resulting in a significantly slower number of pulses/sequence (P < 0.001). However, there was little change in the duration of a pulse sequence. These parameters were not significantly adjusted in most communication vocalizations under the noise condition (all P > 0.05), except that the duration decreased and the number of syllables/sequences increased in 1 type of communicative vocalization (P < 0.05). This study suggests that bats routinely adjust temporal parameters of echolocation but rarely of communication vocalizations in response to noise condition.     

36个燕麦品种不同部位养分分布格局

分析了天祝高寒草甸区36种不同饲用燕麦(Avena sativa)叶片、籽粒和茎秆中的水分、灰分、粗蛋白、可溶性糖、粗脂肪、磷、钙、粗纤维、中性纤维和酸性纤维含量的分布特征。结果显示:36个燕麦品种叶片中水分、灰分、粗蛋白、可溶性糖和钙含量显著高于籽粒和茎秆(P0.05),平均值分别为6.36%、9.28%、19.82%、13.71%和0.25%;籽粒中粗脂肪和磷含量显著高于叶片和茎秆(P0.05),平均值分别为:4.48%和0.25%;茎秆中粗纤维、中性洗涤纤维和酸性洗涤纤维含量显著高于叶片和种子(P0.05),平均值分别为35.62%、65.18%和56.40%。总之,36种燕麦不同部位的营养价值高低依次为叶片籽粒茎秆。     

猪繁殖与呼吸综合征病毒和致病性沙门氏菌的混合感染

2003年9～11月某猪场发生母猪持续性繁殖障碍和7日龄仔猪呼吸困难、寒颤、下痢、体温升高和实质性器官出血为主要特征的疾病。3头发病仔猪的病变组织用RT-PCR检测。均为猪繁殖与呼吸综合征病毒(PRRSV)阳性；由3头发病猪病料中所分离的细菌。可于普通琼脂、伊红美蓝和麦康凯琼脂培养基上生长，革兰氏染色阴性，形态与组织触片镜检及生化反应特性与沙门氏菌一致，可致死小鼠。仅对头孢唑啉呈中度敏感。结合该病的流行病学调查、临床症状、病理剖检，确诊为猪繁殖与呼吸综合征病毒(PRRSV)和致病性沙门氏菌混合感染。     

生物纤维饲料在蛋鸡生产中的应用研究

生物纤维饲料是对玉米淀粉湿磨国工过程中的浸泡液，黄浆和玉米皮渣等副产品经生物发酵方法而形成的一种新型饲料。本文研究了生物纤维饲料在蛋鸡饲养中的饲喂效果。试验表明，半风干生物纤维饲料（含水分26．68％）以5％比例添加蛋鸡日粮中的饲喂效果与对照组相比，日均产蛋量提高6．4％，平均产蛋率提高6．05％，料蛋比下降13．01％，毛利润提高90．70％，而风干生物纤维饲料（含水分15．44％），则以10％比添加于蛋鸡日粮时，表现出较明显的增产效果，其与对照组相比，日均产蛋量提高4．04％，平均产蛋率提高4．18％，料蛋比下降4．09％，毛利润提高25．74％。     

仔猪产气荚膜梭菌肠毒血症病原诊断及疫苗研究IV．肠毒血症C型疫苗生产用菌种的确定

试验证明用单一菌株C59-2生产C型产气荚膜梭菌肠毒血症干粉灭活疫苗,其效力可以达到《规程》要求,并且简化了生产工艺,降低了生产成本,提高了生产效率。疫苗免疫的兔血清可分别中和原来3个制苗用菌株所产生的外毒素。