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Carlos N. Marcos Trinidad de Evan Paloma García‐Rebollar Carlos de Blas Maria Dolores Carro 《Journal of animal physiology and animal nutrition》2019,103(5):1303-1312
Olive oil extraction generates olive cake (OC) that could be used in ruminant feeding. However, the chemical composition of OC is affected by multiple factors, being therefore highly variable. The objective of this study was to analyse the influence of storage time and further processing: crude, exhausted (subjected to a second oil extraction) and cyclone (obtained from a cyclone separator) on nutritive value of OC samples. Twelve samples (six crude and six exhausted) were obtained monthly from the same pond from 1 to 6 storage months, and nine samples (three crude, three exhausted and three cyclone) were obtained monthly from a different pond from 6 to 9 months storage. Chemical composition was analysed, and OC samples were fermented in vitro with sheep rumen fluid. Increasing storage time up to 6 months decreased sugars and total soluble polyphenols content but increased fibre content in OC. Dry matter effective degradability (DMED) decreased linearly (p < 0.001) by 35.9 and 45.5% as storage time augmented from 1 to 6 months for crude and exhausted OC, respectively. Crude OC had lower DMED values than exhausted OC (averaged values 0.255 and 0.294 g/g, respectively). Both potential production and rate of gas production were lower (p ≤ 0.018) in crude compared with exhausted OC, which was attributed to the high fat content of crude OC (≥86 g/kg dry matter). For samples stored longer than 6 months, cyclone had greater (p < 0.05) DMED than crude and exhausted OC (averaged values 0.207, 0.164 and 0.164 g/g, respectively). The results indicate that ruminal degradability of OC is reduced with advancing storage time, but only subtle changes were observed during the first two months. Cyclone showed greater degradability than crude and exhausted OC, but differences between crude and exhausted OC became negligible after five storage months. 相似文献
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P. Lonergan 《Acta veterinaria Scandinavica》1994,35(4):307
Development of mammalian embryos in vitro is functionally and temporally inferior to embryo development as it occurs inside the female reproductive tract. The deficiencies of cultured embryos range from slow cleavage rates to complete developmental arrests or blocks, occurring at particular stages in many species. A variety of approaches have been used to overcome the blocks, including most extensively the coculture of preimplantation embryos with various somatic cells. However, even with coculture, development of embryos in vitro is still not equivalent to that in vivo. In most laboratories, only 25–40% of inseminated oocytes develop into morulae and blastocysts in spite of numerous variations on the basic technique. A better understanding of the factors governing embryonic growth is required before we can hope to achieve results comparable with those occurring in vivo. 相似文献
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Pei-Pei Zhang Jing-Jing Wang Chong-Yang Li Hai-sheng Hao Hao-Yu Wang Wei-Hua Du Yun-Wei Pang Shan-Jiang Zhao Hui-Ying Zou Tong Hao Sha Yang Wei-Min Ruan Jin-Ming Huang Peng-cheng Jiao Hua-Bin Zhu Xue-Ming Zhao 《Reproduction in domestic animals》2020,55(9):1103-1114
The fertilization capacity of sex-sorted sperms is seriously decreased, which inhibits its wide application. However, little information is still available about the effect of vitamin C (VC) and lycopene (Lyc) on the fertilization capacity of sex-sorted bull sperm. In this study, the washing medium and fertilization medium of sex-sorted sperm from three bull individuals were supplemented with different concentrations of VC (0, 1 × 10–3, 1 × 10–4, 1 × 10–5, 1 × 10–6 M) or Lyc (0, 1 × 10–4, 1 × 10–5, 1 × 10–6, 1 × 10–7). After washing twice and incubation for 1.5 hr, the malondialdehyde (MDA) level, phosphatidylserine (PS) translocation, membrane potential (Δψm) and IVF (in vitro fertilization) ability of sex-sorted sperm were investigated. For the sex-sorted sperm of bulls A, B and C, 1 × 10–3 M VC or 1 × 10–4 M Lyc treatment significantly decreased their MDA levels and PS translocation and increased their Δψm levels and cleavage rates after IVF. When blastocysts were concerned, 1 × 10–4 M Lyc significantly improved the blastocyst rates and their IFN-tau expression of bulls A and C. In conclusion, supplementation of 1 × 10–3 M VC or 1 × 10–4 M Lyc in washing and fertilization medium contributed greatly to improving the fertilization capacity of sex-sorted bull sperm during IVF procedure. 相似文献
26.
对退耕还林工程中种草的探讨 总被引:6,自引:0,他引:6
分析种草在退耕还林工程中的重要地位和作用 ,提出退耕种草的草种选择和种植模式 ,并探讨发展草产业的途径和方向 相似文献
27.
本研究目的在于制备抗猪带绦虫TSOL18单克隆抗体,并分析单抗对六钩蚴的杀伤作用。采用SephadexG-100纯化在毕赤酵母中表达的猪带绦虫六钩蚴TSOL18蛋白;纯化的蛋白免疫BALB/c小鼠,运用杂交瘤技术建立能分泌抗TSOL18单克隆抗体的细胞株;通过ELISA叠加试验进行mAb的抗原表位分析;采用间接ELISA法测定TSOL18单克隆抗体特异性及腹水效价;采用抗TSOL18单克隆抗体对激活的猪带绦虫六钩蚴进行体外六钩蚴杀伤试验,观察单抗对猪带绦虫六钩蚴活力的影响。结果成功获得12株稳定分泌抗TSOL18单克隆抗体的杂交瘤细胞株,识别2个不同抗原表位,不同抗原表位的2株单克隆抗体腹水效价分别为1×102、1×106。抗体体外六钩蚴杀伤试验结果证明,在有补体的情况下,多抗和单抗作用6 d后,六钩蚴结构模糊,边缘不清晰。表明单抗对六钩蚴有一定的杀伤作用。 相似文献
28.
百合组织培养和植株再生的研究进展 总被引:1,自引:0,他引:1
综述了百合组织培养和植株再生技术,着重介绍了百合离体快繁、愈伤组织与植株再生、体细胞诱导等方面的研究内容。 相似文献
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选用DEAE-纤维素离子交换柱对双峰驼精清进行分离,各层析组分用于大鼠垂体组织体外培养,并给母驼肌注有活性的组分,以RIA法测定垂体组织培养液和母驼血浆中LH及FSH的浓度。结果表明,驼精清经DEAE-纤维素柱分离后可得到5个蛋白组分(L1-L5),其中L3在大鼠垂体培养时引起LH释放明显增加(P<0.05),FSH则无明显变化。给卵巢上无大卵泡发育的母驼肌注有活性的组分L3,可引起血浆中LH明显升高,FSH也无变化。由此表明,L3在体内外试验中均具有引起LH释放的生物活性,它可能是诱导排卵的活性因子或其成分之一。 相似文献