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动物的性别不同、生长速度、形态、风味等亦不尽相同出于某种需要,有时要进行雌雄鉴别。在动物的繁殖工作中更需要准确识别雌雄、以便于亲本选留、购进及组配。比如中华鳖.在正常条件下.雄鳖比同龄雌鳖的生长速度要高出10%~20%、多养雄鳖能显著提高经济效益。但中华鳖在繁殖配组时.雌雄比为3:1最适宜。若雄性比例过大.不但浪费饲料.而且干扰雌鳖的正常生殖。所以正确的雌雄鉴别在动物的养殖中具有重要价值。1美国青蛙是我国80年代后期从美国引进的大型肉蛙良种.国内养殖规模日益扩大。其雌雄鉴别:雄蛙咽喉呈明显金黄色,有咽下… 相似文献
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黑龙江林蛙繁殖期两性皮肤组织结构的差异比较 总被引:1,自引:0,他引:1
报道了繁殖期黑龙江林蛙皮肤及其腺体的显微结构特点及两性差别。研究发现:黑龙江林蛙雌雄个体在皮肤特定部位的表皮厚度和皮肤总厚度上存在显著差异;雌蛙各部位真皮致密层都比雄蛙相应部位的致密层厚,且有显著差别。雌雄性蛙色斑不仅存在两性差异,而且构成色斑的色素细胞数量雄蛙明显多于雌蛙;皮肤腺在组成类型和分布上雌雄也有差别,最明显的是雄蛙躯干的背、腹部存在有大量的特殊黏液腺,讨论了这种特殊的黏液腺在生殖行为中可能产生一些化学交流信号和辅助抱对作用。 相似文献
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过冷却处理家蚕卵对四倍体诱发率及后代性比的影响 总被引:3,自引:1,他引:2
探讨了家蚕盛产卵后不同时间的卵过冷却处理对四倍体诱发率和后代三倍体性比发生的影响。不同杂交组合材料盛产卵后不同时间卵所处的分裂期不同 ,影响到四倍体雌蚕的诱发率 ,处于第一分裂期的卵数越多 ,诱发率越高 ;诱发的四倍体与正常二倍体交配产生的三倍体蚕雌雄比例由 3∶1变为 5∶1是由于四倍体减数分裂中性染色体的行为 ,性比 3∶1时 ,仅是Z与Z、W与W之间的联会 ,其后随着这种联会增加 ,Z与W之间的联会也逐渐开始 ,从而使雌雄比例接近 5∶1。 相似文献
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二、牛蛙的人工繁殖 1.种蛙的选择和培育:牛蛙一般1~2龄可达性成熟。选作繁殖的种蛙应以2~3龄、体重在300克以上,体质强壮,发育良好,无伤无病,善跳跃活泼的成蛙为佳。种蛙雌雄蛙来源要注意本地与异地结合,防止近亲交配繁殖、后代性状退化。从外地引进种蛙必须在开春前进池,在本场越冬,以利春天繁殖。雌、雄蛙为1:1为宜,最大不超过1.5:1,即雌性可略多于雄性,否则影响受精率和孵化率。在个体上差异不能悬殊,以利抱对。雌、雄蛙一 相似文献
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蒋张林 《河南畜牧兽医(综合版)》2002,23(12):40-40
具有近20年养龟历史的浙江海宁市袁花镇科协养龟场在实践中发现,雌龟性成熟早,雄龟性成熟晚,这就影响先期性成熟雌龟没有性成熟雄龟给予有效交配,致使所产龟卵未受精或受精率偏低。在生产中进行调整雌雄龟性别比、雌雄龟错位养,增加雄龟营养添加剂等有效措施,取得了十分明显的效果。使原来初产孵受精率由20%左右提高到80%以上,效益大大提高。具体做法是:1提高雌雄龟性别比从常规养龟的雌雄龟比例的2~3∶1,调整为2∶1~2。使每只雌龟有雄龟及时交配,因为有基本相等的两性比例,可以提供更多的交配机会,从而提高了… 相似文献
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采用悬浮灭活试验,以鸡胚感染法,研究奇露、卫可、泛福露益选3种消毒剂在一系列浓度下,分别与H5N1和H5N2亚型禽流感病毒作用5,10min,对禽流感病毒的灭活作用。结果表明:1:200、1:280、1:400、1:800、1:1000浓度的卫可,1:320、1:600、1:800、1:1000浓度的泛福露益,1:200、1:400、1:600浓度的奇露对四亚型禽流感病毒可完全灭活31:200、1:280、1:400、1:800浓度的卫可,1:320、1:600、1:800浓度的泛福露益,1:200、1:400浓度的奇露对比亚型禽流感病毒可完全灭活。 相似文献
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应用体外培养的泰氏锥虫制备可溶性抗原Ⅰ、抗原Ⅱ和代谢抗原.经测定,其蛋白含量每毫升分别为6.5mg、7.4mg和7.1mg.薄层等电聚焦电泳测定结果表明,抗原Ⅰ出现22条区带,抗原Ⅱ21条区带,代谢抗原28条区带,对照的伊氏锥虫琼脂免疫扩散抗原14条区带.经分析,泰氏锥虫抗原和伊氏锥虫抗原有4条区带在同一迁移率上.琼脂免疫扩散反应中,3种泰氏锥虫抗原均与相应免疫兔血清发生沉淀反应,抗原Ⅰ出现1条致密沉淀线,抗原Ⅱ和代谢抗原出现2~3条沉淀线,抗原效价为1:4~16.免疫电泳显示了类似的结果,抗原Ⅰ与免疫兔血清出现1条弧形沉淀线,抗原Ⅱ和代谢抗原与免疫兔血清出现了3条弧形沉淀线.间接血凝试验结果表明,泰氏锥虫自然感染牛血清效价为1:20~40,免疫兔血清为1:1280~5120.所制泰氏锥虫抗原对伊氏锥虫和媾疫锥虫血清也能很好地发生交叉反应,3份伊氏锥虫病马血清和3份伊氏锥虫人工感染兔血清血凝效价分别为1:10~40和1:8~1024;5份媾疫马血清有4份血凝效价为1:20~320.4份环形泰勒虫病牛血清均为阴性. 相似文献
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Effects of Dilution Rate on the Motility and Acrosome Morphology of Boar Spermatozoa Stored at 15 °C
C. Perez Marcos R. Sanchez M. Palacio V.G. Pursel T. Perez Garcia S. Martin Rille 《Reproduction in domestic animals》1991,26(3):112-116
The objective of this investigation was to establish the optimal extent of dilution for storage of boar spermatozoa at 15°C in Kiev diluent. The dilution titers used for the sperm-rich fraction of ejaculates from 8 boars ranged from 1:2 to 1:50. Seminal doses were stored for 10 days. Motility and acrosome morphology were evaluated after 1, 3, 5, 7, and 10 days of storage. The percentages of motile spermatozoa after 24 and 72 hours of storage were significantly higher for dilution rates between 1:7 and 1:11 than for dilution rates lower than 1:7 or higher than 1:11 (p < 0.05). The percentages of spermatozoa with normal acrosomes after 24, 72, and 120 hours of storage were significantly higher for dilution rates between 1:8 and 1:11 than for dilution rates lower than 1:8 or higher than 1:11 (p < 0.01 ). 相似文献
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Cañón-Franco WA Yai LE Souza SL Santos LC Farias NA Ruas J Rossi FW Gomes AA Dubey JP Gennari SM 《Veterinary parasitology》2004,123(3-4):275-277
Domestic dog (Canis domesticus) and the coyote (Canis latrans) are the only known definitive hosts for the protozoan Neospora caninum that causes abortion in dairy cattle. In the present study, antibodies to N. caninum were sought in three species of wild canids, Cerdocyon thous, Lycalopex gymnocercus and Dusicyon vetulus from Brazil. Antibodies to N. caninum were assayed by the indirect fluorescent antibody test (IFAT) and the Neospora agglutination test (NAT). N. caninum antibodies were found in five of 12 L. gymnocercus with IFAT titers of 1:50 in three, 1:100 in one, and 1:1600 in one, and NAT titers of 1:40, 1:80, 1:160, 1:320, and 1:640 in five animals. Antibodies to N. caninum were found in four of 15 C. thous with IFAT titers of 1:50 in one, and 1:100 in three, and NAT titer of 1:40 in one animal. All 30 D. ventulus were seronegative by IFAT and NAT. 相似文献
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本试验旨在筛选自然发酵苜蓿青贮的优势菌种,应用于高水分苜蓿青贮的调制,研究不同微生物及组合对高水分苜蓿青贮品质的影响。试验先调制自然发酵苜蓿,青贮30 d后,从中筛选优势菌种并进行鉴定。根据优势菌种筛选结果,组合了9组发酵菌种用于苜蓿青贮的调制,分别为:以植物乳杆菌与乳酸片球菌为发酵菌种,活菌数比例分别为1∶1、1∶2和2∶1,编号为1、2、3组;以植物乳杆菌、枯草芽孢杆菌和乳酸片球菌为发酵菌种,活菌数比例分别为2∶1∶1、1∶1∶1和4∶1∶1,编号为4、5、6组;以植物乳杆菌、解淀粉芽孢杆菌和乳酸片球菌为发酵菌种,活菌数比例分别为2∶1∶1、1∶1∶1和4∶1∶1,编号为7、8、9组;以不加任何菌种的自然苜蓿青贮作为对照。每组3个重复,发酵60 d后,对苜蓿青贮进行感官评定,并测定氨态氮/总氮(NH3-N/TN)、总酸含量和pH。结果表明:用MRS、LB和NA 3种培养基从自然发酵苜蓿青贮中筛选到微生物菌种31株,对其中18株进行了分子鉴定,主要菌种为植物乳杆菌9株、乳酸片球菌1株、粪肠球菌2株、各种芽孢杆菌6株。感官评分结果表明乳酸菌(植物乳杆菌和乳酸片球菌)比例大的各组评分等级显著高于对照组和添加了添加枯草芽孢杆菌的各组(P<0.05)。对于NH3-N/TN、总酸含量和pH等指标,乳酸菌比例较低的2、5、8和对照组与其余各组差异显著(P<0.05)。综上所述,植物乳杆菌和乳酸片球菌是苜蓿青贮主要菌种,用于苜蓿青贮有利于青贮品质的提高。枯草芽孢杆菌会影响苜蓿青贮的气味,解淀粉芽孢杆菌为菌种会改善苜蓿青贮风味,但比例太高会增加NH3-N含量。 相似文献
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为探究亚油酸对反刍动物瘤胃中溶纤维丁酸弧菌脂肪酸合成的影响,试验用不同水平亚油酸培养基进行溶纤维丁酸弧菌体外厌氧培养试验,分光光度计测定菌液D600 nm值达到1.0时,在培养基中添加亚油酸,使试验1组(对照)、2、3及4组培养基亚油的浓度分别为0、2.5、5.0及7.5 mg/100 mL,培养24 h后收集菌液检测35种脂肪酸含量。结果显示,细菌代谢相关的C8:0、C11:0、C14:0、C15:0、C17:0、C17:1、C18:1(n-9) C、C18:2(n-6) C、C18:3(n-6)、C20:0、C20:2、C20:3(n-3)、C20:3(n-6)、C20:5(n-3)、C21:0、C22:0、C22:2、C22:1(n-9)及C22:6(n-3)脂肪酸随着培养基中亚油酸浓度的提高无显著变化(P>0.05);培养基中添加亚油酸使C10:0、C12:0、C16:0、C18:0、C20:4(n-6)、C23:0、C24:1合成量显著减少(P<0.05);而C15:1及C18:3(n-3)合成量在2.5 mg/100 mL亚油酸组显著增加(P<0.05);C14:1在对照组中合成量最高,在添加亚油酸的试验组中,随着亚油酸含量增加而增加;C24:0在7.5 mg/100 mL亚油酸组合成量最高。综上所述,亚油酸对于溶纤维丁酸弧菌合成脂肪酸有一定影响作用,可抑制C10:0、C12:0、C16:0、C18:0、C23:0、C14:1、C20:4(n-6)等脂肪酸的合成,C15:1、C16:1、C18:3(n-3)含量增加,但超过一定量时合成量会减少。 相似文献
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Whole blood in vitro assays were used to determine the potency and selectivity of carprofen enantiomers for inhibition of the isoforms of cyclooxygenase (COX), COX-1 and COX-2, in the calf. S(+)-carprofen possessed preferential activity for COX-2 inhibition but, because the slopes of inhibition curves differed, the COX-1:COX-2 inhibition ratio decreased from 9.04:1 for inhibitory concentration (IC)(10) to 1.84:1 for IC(95). R(-) carprofen inhibited COX-2 preferentially only for low inhibition of the COX isoforms (IC(10) COX-1:COX-2=6.63:1), whereas inhibition was preferential for COX-1 for a high level of inhibition (IC(95) COX-1:COX-2=0.20:1). S(+) carprofen was the more potent inhibitor of COX isoforms; potency ratios S(+):R(-) carprofen were 11.6:1 for IC(10) and 218:1 for IC(90). Based on serum concentrations of carprofen enantiomers obtained after administration of a therapeutic dose of 1.4mg/kg to calves subcutaneously, S(+)-carprofen concentrations exceeded the in vitro IC(80) COX-2 value for 32h and the IC(20) for COX-1 for 33h. The findings are discussed in relation to efficacy and safety of carprofen in calves. 相似文献
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K. K. Qi J. L. Chen G. P. Zhao M. Q. Zheng J. Wen 《Journal of animal physiology and animal nutrition》2010,94(4):474-485
The effects of varying the ω6 to ω3 fatty acid ratio (ω6/ω3) of diets on growth performance, carcass traits, meat quality and fatty acid composition of breast muscle were investigated in Beijing‐you chickens grown to 92 days. A total of 360 one‐day‐old female BJY chickens were fed diets containing 0%, 0.12%, 0.42%, 1.00% or 1.97% linseed oil replacing equal weights of maize oil to make dietary ω6/ω3 to be approximately 30:1, 20:1, 10:1, 5:1 and 2.5:1. Subcutaneous fat thickness and intramuscular fat content increased significantly in birds fed up to 10:1 ω6/ω3. a* values (redness of meat, dimension of the CIELAB‐system) progressively increased as the diets contained increasing ω3 content, up to the 10:1 ω6/ω3.The changes in b* (yellowness of meat, dimensions of the CIELAB‐system) were also significant but the pattern was almost the reverse of changes in a*. Shear force increased significantly as dietary ω6/ω3 was reduced from 30:1 to 5:1. Decreasing the dietary ω6/ω3 clearly decreased the content in breast muscle of C20:1 and C22:1, but increased that of C24:1. C20:4, C20:5 and C22:5, increased significantly by decreasing the dietary ω6/ω3, and the birds fed the 10:1 diet had higher contents of C22:6 than other treatments. This study has clearly demonstrated that decreasing the dietary ω6/ω3, increases the deposition of desirable ω3 and ω6 long chain PUFA in the edible tissue, thereby achieving nutritionally enriched meat. 相似文献