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Four transplant studies are described that focus on fertilisation and early development or the progression of unfertilised oocytes (eggs) in the oviduct.(1) Pig eggs transplanted from ovulations induce... 相似文献
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目前蚕种场系统面临困境,本文就此进行了原因分析,并就茧量平衡,提高经营水平,综合开发,政策引导,科技改良等方提出了对策 。 相似文献
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营养水平对仔猪断奶综合征的影响 总被引:2,自引:0,他引:2
试验选取杜×长×大三元杂交仔猪,随机分为2个处理组,每个处理3个重复,每个重复10头仔猪.试验组饲喂5008配合日粮.对照组饲喂5000配合日粮.针对仔猪断奶综合征的表现特征,分别测定各组猪生长性能和腹泻率等指标.试验结果表明,饲粮中合有高水平的蛋白质及能量对断奶仔猪有促生长作用,可缓解仔猪断奶综合征的发生. 相似文献
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蚕桑多元化发展是产业发展的方向,现主要集中于蚕桑资源综合利用,产业附加值低,产业水平亟待提高。生物防治的安全性、高技术含量和高附加值为产业的壮大提供了广阔市场前景。柞蚕卵繁育寄生蜂技术较为成熟,已经大量生产和推广。利用蚕桑副产物生产生物农药,开展生物防治,可成为蚕桑多元化发展的新方向。 相似文献
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Yi-Chao Chen Ren-Bao Liaw Yu-Sheng Liao Amornrat Wanangkarn Wen-Shyan Chen Fa-Jui Tan 《Animal Science Journal》2021,92(1):e13567
A novel animal protein-based douchi koji-inoculated steamed salted egg white sufu (SEWS) has been developed. This study determined the relative abundance of microorganisms in the douchi koji and semi-finished (5-day fermentation) and finished (5-day fermentation and 14-day ripening) SEWS by using 16S and 18S ribosomal DNA and gene-cloning methods. The results revealed that Bacillus spp. and Aspergillus oryzae were dominant in the douchi koji. In the semi-finished SEWS, the percentages of Bacillus amyloliquefaciens and Bacillus subtilis were considerably lower, whereas those of Enterococcus and Staphylococcus were substantially higher. In the finished SEWS, Bacillus spp. became dominant again and A. oryzae was the only fungus detected. In conclusion, by using molecular techniques, microbial population dynamics in SEWS can be evaluated. During processing, the relative abundance of microorganisms in SEWS changed and Bacillus spp. and A. oryzae remained dominant. This study provides crucial information for designing starter cultures for producing SEWS. 相似文献
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This study compared the postthaw semen parameters of stallions with high and low body condition score (BCS) and evaluated associations between body morphometric parameters and postthaw semen parameters. Twenty stallions were split into Low BCS (BCS<7, n = 11) and High BCS (BCS ≥7, n = 9) groups, and underwent a complete morphometric analysis (e.g., neck scores and circumference, crest neck height, body weight, and height), and subcutaneous body fat thickness (SFT) at the tail head, withers, shoulders, and retroperitoneal space. A fasted oral sugar test (OST) was conducted on all stallions. One ejaculate from each stallion was frozen with a commercial egg yolk-based extender. Postthaw sperm motility parameters, plasma membrane integrity, mitochondrial membrane potential, hydrogen peroxide and intracellular superoxide production, and lipid peroxidation were analyzed for all stallions. The circumference at 25% and 50% of the neck’s length were larger for High-BCS stallions (P < .05). There were no differences between groups for the neck crest height (P > .05). Stallions with High BCS had greater SFT at the tail head than stallions with Low BCS (P < .05); however, there were no differences between groups in the SFT at the shoulders and withers (P > .05). All stallions had resting blood glucose below the cutoff for equine metabolic syndrome. There were no differences between groups for resting glucose concentrations or for a peak at 30 or 60 minutes after initiation of the OST (P > .05). There were no differences in sperm parameters between groups (P > .05). Collectively, the findings of the present study suggest that High BCS or Low BCS in the presence of normal OST do not explain post-thaw semen parameters. 相似文献