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61.
This experiment was conducted to study the effects of different levels of compound Chinese medicine on growth performance,nutrients apparent digestibility,immune function and slaughter performance of weaning Rex rabbits.70 healthy Rex rabbits at age of 60 days were divided into 7 groups with 5 replicates per group and 2 rabbits per replicate.Group Ⅰ was fed with basic diet as control group,group Ⅱ was fed the basal diet supplemented with antibiotic (contains 50 mg/kg milligrams bacitracin zinc,10 mg/kg colistin sulfate).The other five groups (Ⅲ,Ⅳ,Ⅴ,Ⅵ and Ⅶ) were fed the basal diet supplemented with 1%,2%,3%,4%,5% compound Chinese medicine,respectively.The pre-test period lasted for 7 days and the trial period lasted for 45 days.The results showed as follows:①The ADG in group Ⅳ was significantly higher than that in groups Ⅰ,Ⅱ and Ⅲ (P< 0.05),the F/G in group Ⅳ was significantly lower than that in other groups (P< 0.05).②The apparent digestibility of DM in group Ⅳ was significantly higher than that in groups Ⅰand Ⅱ (P< 0.05),the apparent digestibility of DM in group Ⅶ was significantly higher than that in group Ⅰ (P< 0.05).The apparent digestibility of CF in group Ⅳ was extremely significantly higher than that in group Ⅰ (P< 0.01),the apparent digestibility of CF in group Ⅶ was significantly higher than that in group Ⅰ (P< 0.05).The apparent digestibility of NDF in group Ⅳ was extremely significantly higher than that in group Ⅰ (P< 0.01),and significantly higher than that in groups Ⅱ,Ⅲ,Ⅴ and Ⅶ (P< 0.05).The apparent digestibility of ADF in group Ⅳ was significantly higher than that in groups Ⅰ,Ⅱ,Ⅴ and Ⅶ (P< 0.05).The apparent digestibility of CP in group Ⅳ was significantly higher than that in groups Ⅰ and Ⅱ (P< 0.05).③ There were no significant differences in the contents of IgG,IgA and IgM of serum among all groups (P> 0.05),the spleen index in group Ⅳ was significantly higher than that in groups Ⅰ,Ⅱ,Ⅲ and Ⅴ (P< 0.05).④There were no significant differences in the slaughter rate,half eviscerated slaughter rate and all eviscerated slaughter rate among all groups (P> 0.05).In summary,adding compound Chinese medicine and antibiotics in the feed both could improve the growth performance,nutrients apparent digestibility,immune function and slaughter performance of weaning Rex rabbits,and the appropriate compound Chinese medicine level in the diet of weaning Rex rabbits was 2%.  相似文献   
62.
【目的】掌握渝西地区兔球虫病的流行情况和兔球虫种类,为该地区兔球虫病的防治提供依据。 【方法】采用饱和食盐水漂浮法和麦克马斯特氏计数法检测渝西荣昌、永川、大足等 8 个区 14 个兔场共 1 273 份 粪样本,并收集卵囊,鉴定兔球虫种类。【结果】发现 14 个兔场均有感染球虫,平均感染率为 90.65%,璧山 和江津的感染率最高,为 100%,2 月龄以下兔感染率极显著高于 2~4 月龄、4~9 月龄及 9 月龄以上年龄段兔, 感染率为 98.19%。小型养殖场兔球虫感染率极显著低于大型规模化养殖场,感染率为 86.53%。8 个区的克粪便 虫卵数(Oocysts Per Gram,OPG)为 9.65×103 ~6.56×104 ,其中 2~4 月龄 OPG 最高、为 6.31×104 。对药物使 用情况调查显示,未使用球虫药养殖场的感染率为 92.31%,OPG 为 4.42×104 ; 使用球虫药养殖场的感染率为 89.19%,OPG 为 2.75×104 。在 14 个兔场共鉴定了 10 种艾美耳球虫,其中优势虫种为穿孔艾美耳球虫(Eimeria perforans)、大型艾美耳球虫(E. magna)、盲肠艾美耳球虫(E. coecicola)和中型艾美耳球虫(E. media), 检出率分别为 25.20%、23.38%、11.96%、10.02%。【结论】渝西地区普遍感染兔球虫,且多为混合感染,因此 应加强该地区兔球虫病的防治。  相似文献   
63.
We examined the distribution of sardine larvae relative to environmental conditions with the purpose of identifying and characterizing habitat that encourages high larval growth and survival, based on the 1983–1998 surveys of the California Cooperative Oceanic Fisheries Investigations (CalCOFI). Long-term averages show that sardine 'survivors' (spatially aggregated larvae ≥ 18 days old) were most abundant offshore, whereas sardine egg density, chlorophyll biomass and zooplankton volume were greatest inshore. In contrast, mesoscale eddies, observed in remotely sensed sea surface temperature imagery, were found only in offshore regions. To further examine the link between eddies – which often result in locally elevated chlorophyll and zooplankton – and sardine survival, we compared the distribution of larvae and eddies survey by survey. Sardine survivors were most abundant offshore in only one-quarter of the research surveys, and when they were most abundant offshore they were associated with eddies. This indicates that the offshore eddy habitat produced exceptionally large numbers of survivors, as evidenced by the disproportionate effect on the long-term average.  相似文献   
64.
The primary function of the placenta is to act as an interface between the dam and fetus. The anatomic structure of the chorioallantoic placenta in eutherian mammals varies between different animal species. The placental types in eutherian mammals are classified from various standpoints based on the gross shape, the histological structure of the materno-fetal interface, the type of materno-fetal interdigitation, etc. Particularly, the histological structure is generally considered one of the most useful and instructive classifications for functionally describing placental type. In this system, three main types are recognized according to the cell layers comprising the interhemal area: (1) epitheliochorial type (horses, pigs and ruminants), (2) endotheliochorial type (carnivores) and (3) hemochorial type (primates, rodents and rabbits). The number of cell layers in the interhemal area is considered to modify the transfer of nutrients between maternal and fetal blood and is one of the important factors with respect to the difference in placental permeability between animal species. Therefore, in reproductive and developmental toxicity studies, careful attention should be paid to the histological structure of the interhemal area when extrapolating information concerning placental transfer characteristics to different animal species.  相似文献   
65.
66.
Seasonal assemblages of mesopelagic fish larvae and changes related with environmental factors (plankton biomass, sea surface temperature anomaly, upwelling, and the multivariate El Niño index) were investigated. From 1982 to 1987, 16 oceanographic cruises were carried out along the Pacific coast of Baja California Sur, Mexico. Larvae of 42 mesopelagic fish taxa were collected. Larval abundance was highly variable during the studied period, but summer months coincided with higher abundance (>200 larvae under 10 m2). Larval assemblages were dominated by three of the most common species of tropical (Vinciguerria lucetia, Diogenichthys laternatus) and subtropical affinity (Triphoturus mexicanus). A group of species of tropical affinity (Diplophos proximus, Diaphus pacificus, Benthosema panamense) was useful for distinguishing the 1982–84 El Niño event, and an assemblage of larvae of temperate affinity (Symbolophorus californiensis, Melamphaes lugubris, Bathylagus ochotensis, Leuroglossus stilbius, Protomyctophum crockeri) characterized ‘normal’ years (mid‐1984 to mid‐1987).  相似文献   
67.
[目的]为找出陕西地区奶牛隐型乳房炎的临界点。[方法]采用生产上常用的乳房炎诊断方法,通过间接测定乳中体细胞数来诊断乳房炎的发生。[结果]找出体细胞数在47.46万以上时才依次表现出弱阳性、阳性、强阳性的特征。[结论]从而依据以上结果制定出两种方案用于预防和治疗乳房炎的发生。  相似文献   
68.
文章分析了3种方式(剪毛、直接拔毛和药物拔毛)对皖系长毛兔采毛前、采毛后0、4、8、24、48 h血清蛋白及含氮代谢物变化规律的影响.结果发现:3种采毛方式均显著上调血清总蛋白和肌酐水平,而血清白蛋白仅受药物拔毛影响而显著上调;药物拔毛显著上调血清总胆红素和直接胆红素水平,同时直接胆红素还受其他两种采毛方式影响而显著下调;两种拔毛方式(直接拔毛和药物拔毛)显著上调血清尿素和尿酸水平,但剪毛对这两个指标没有影响.长毛兔在采毛后48 h内,多数血清指标可恢复到采毛前水平,或呈恢复趋势;该研究筛选获得采毛应激指标血清总蛋白和肌酐,拔毛应激指标尿素和尿酸,同时发现肌酐、白蛋白和胆红素受地塞米松的显著影响.该研究结果可为初步揭示不同采毛方式应激生化机制提供参考.  相似文献   
69.
为了解楚雄州部分地区的猪瘟免疫情况,利用酶联免疫法(ELISA)对楚雄市、南华县和禄丰县随机采取的393份血清进行猪瘟抗体检测,并对各县(市)的调查数据加以比较,了解猪瘟在楚雄州部分地区的免疫情况。结果显示,楚雄州部分地区均有较高的猪瘟抗体阳性率,各县(市)的猪瘟抗体阳性率都在80%以上,有的县(市)猪瘟抗体甚至达到了100%。说明楚雄州部分地区的猪瘟免疫效果较好,猪瘟免疫成功。  相似文献   
70.
本试验旨在探讨饲粮能量水平对42 d繁殖模式下獭兔繁殖性能、体重变化及血清生化指标的影响.试验选用平均体重为(3.56±0.17) kg的经产獭兔150只,随机分成3组,每组50个重复,每个重复1只.采用42 d繁殖模式,分别饲喂消化能水平为9.2、9.7和10.2 MJ/kg的试验饲粮.试验连续进行3胎.结果表明:1)饲粮能量水平极显著影响母兔泌乳力(P=0.0062)、第1胎产后体重(P=0.002 1)和仔兔断奶窝重(P=0.000 6);显著影响第1胎(P=0.047 5)和第3胎(P=0.030 2)母兔泌乳期第21天体重.2)饲粮能量水平极显著影响血清肌酸激酶(P=0.001 5)活性和甘油三酯(P=0.001 3)含量,显著影响高密度脂蛋白胆固醇(P=0.036 8)、总胆固醇(P=0.047 6)和胰岛素含量(P=0.015 9),对其他血清生化指标无显著影响(P>0.05).由此可见,42 d繁殖模式下獭兔适宜饲粮消化能水平为10.2 MJ/kg.  相似文献   
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