白血病抑制因子在雌性哺乳动物生殖过程中的作用

白血病抑制因子是一种多功能的细胞因子,与哺乳动物的生殖过程密切相关,在排卵、胚胎发育及胚胎着床等过程中起重要的调节作用。母体激素和细胞因子可通过调控白血病抑制因子的表达而影响生殖过程。在此,对LIF在雌性哺乳动物生殖过程中的作用进行了综述。     

青虾人工繁殖研究初报

青虾怀卵量与个体大小呈正相关 ,相对怀卵量在 6 0 0— 70 0粒 / g之间 ;统计出青虾雄雌性比在繁殖早期为 1.10 7:1、产卵盛期为 1.4 39:1;同时观察记录了青虾生殖蜕皮、交配、产卵、孵化全过程。     

硒对公鸡睾丸发育的组织病理学研究

300只海兰白公鸡雏平均分为6组,对照组(CK)饲喂基础日粮,基础日粮含硒量为0 028～0 033mg/kg,Ⅰ～V组分别补硒1mg/kg、5mg/kg、10mg/kg、15mg/kg、20mg/kg,在22周龄屠宰,观察睾丸组织结构。结果表明,对照组CK因缺硒睾丸曲精细管发育受阻,Ⅰ组曲精细管发育良好,曲精细管生精上皮细胞层数多、管壁厚,管径大,精子簇密集;Ⅱ～V组随着日粮硒含量的增加,中毒症状趋于明显,曲精细管管腔变得空大,管壁部分溶解。通过观察与分析,建议公鸡日粮中含硒量以不超过1mg/kg为宜。     

9TW1型兔用育仔电热片设备的研制及其应用

北方地区,冬季繁殖仔兔成活率,不足40％,为了提高冬季仔兔的成活率与增重率,研制了温控育仔电热片设备。通过三年的试验,用温控育仔电热设备育仔成活率达81％,日增重19.6g。对照组及大群生产成活率为40％,日增重12.9g,试验组比对照组与大群生产成活率提高102％,增重率提高65％。     

The influence of feeding patterns on growth and reproduction of the vermicomposting earthworm Eisenia fetida (Oligochaeta)

Summary Observations in outdoor culture beds indicated that food availability and frequency of feeding influenced worm density. In order to study the role of feeding status on the growth and reproduction of Eisenia fetida, pre-clitellate specimens were kept for 180 days under controlled conditions. A control group was regularly provided with freshly produced cattle manure while the experimental groups were fed only sporadically and at some stage even starved by removing some of the substrate. Worm growth, maturation, and cocoon production were monitored. The role of food availability was highlighted by this study. Both worm growth and cocoon production were correlated closely with the feeding pattern that was followed. This study also showed that freshly produced, urine-free, cattle manure proved an excellent food source provided it was added in such a way as to prevent the development of anaerobic conditions. Regular feeding gave high growth and reproduction rates.     

Internal regulation of reproduction seasonality in earthworm Dendrobaena octaedra (Savigny, 1826) (Lumbricidae, Oligochaeta)

The study was conducted on Dendrobaena octaedra—a small epigeic earthworm species common in different forest types. In the laboratory the P (parent animals collected in forest) and F1 generations were cultured separately in containers filled with 50 g artificial soil. The containers were kept at 15±0.5 °C, 80% humidity and constant artificial light of low intensity. Every month during the 47 months of culture, the animals and cocoons were removed from the soil by washing on a sieve, weighed, and replaced into new soil. Individuals of the F1 generation did not reproduce continuously. Cocoon production was seasonal, despite culture in constant conditions throughout the whole experiment. Reproduction was highest in spring and summer, and dropped in the winter months. Seasonality characterized the fraction of animals reproducing as well as the number of cocoons produced. The observed seasonal changes in the cocoon production of the F1 generation cultured in constant conditions suggest that internal regulation of reproduction may exist in the earthworm D. octaedra. External factors like temperature, moisture, photoperiod or food supply, which could be responsible for seasonality of reproduction were missing.     

不同营养水平精饲料对初产萨能奶山羊生长及繁殖性能的影响

[目的]为云南省奶山羊产业的发展提供参考.[方法]在初产.萨能奶山羊日粮中添加低、中、高水平的精料,探讨不同精料水平对初产萨能奶山羊的生长及繁殖性能的影响.[结果]补饲中、高水平的精料后,初产萨能奶山羊的妊娠增重及产后失重均有一定程度提高,但其产羔率、羔羊初生重、产奶量和育成增重等繁殖性能均没有太大改善.[结论]综合考虑养殖成本及奶山羊后续生产,建议在生产中采用中营养水平精料对妊娠期和哺乳期的初产萨能奶山羊进行补饲.     

成都麻羊研究

本文通过对成都麻羊的系统研究。揭示了该羊皮张品质优异、肉用性能好、繁殖力强、较早熟、乳脂含量高,但泌乳力低,没有毛用价值。应归属于普通肉用山羊品种。建议充分利用其早熟、高繁殖力、乳脂率高等优良遗传性状。     

番红花种球定量留芽增产效果研究简报

为实现番红花球茎高产,提高繁殖率,开展了番红花种球定量留芽田间试验。结果表明:26～30 g的大球茎留3芽、18～25 g的中球茎留2芽、18 g以下的小球茎留1芽为合理留芽量。     

不同繁殖代数对烟草品种性状影响

[目的]研究不同年代采收和不同繁殖代数对烟草(Nicotiana tabacum)品种性状的影响。[方法]烟草品种分别为吉烟七号、翠碧一号、K346、NC82和V2,对不同烤烟品种的种子进行田间种植试验。[结果]不同烟草品种间以NC82现蕾较早,翠碧一号和吉烟七号等现蕾较晚;对同一品种不同年代的种子而言,随着繁种代数的增加,吉烟七号、翠碧一号、V2等品种的种子现蕾期推迟,其中吉烟七号、翠碧一号、V2较早年份或较早代的种子现蕾期要比较晚年份或较晚代数的种子早2～9 d。随着种子繁殖代数的增加,多数品种叶片的长和宽增大,导致叶片变大,叶片数增多或减少。不同品种不同年代的种子产量无显著差异,产值、上等烟比例、均价等有显著差异。随着年代或繁殖代数的延长,翠碧一号、NC82和V2等品种的种子产值下降,各品种最晚一代的种子均价比最早一代的低。[结论]该研究可为烟草种子繁殖代数的相关研究提供指导。