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152.
近年来,饲料资源短缺已成为我国饲料行业和畜牧业发展的瓶颈,而干酒糟及其可溶物(DDGS)具有营养丰富、产量较大、饲用安全等特点,已在畜禽生产中广泛应用.本文介绍了DDGS的营养价值及特点,并对其在猪、鸡和反刍动物生产中应用情况进行了综述,供同行参考. 相似文献
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154.
种蛋保存条件对孵化效果的影响 总被引:1,自引:0,他引:1
在平均温度16.5℃,相对湿度75%的条件下,根据种蛋的保存时间(1~3d、4~6d、7~9d,10~12d)、放置方式(锐端向上、锐端向下)、翻蛋与否,将入孵蛋分为16个处理组,与大批量的种蛋同机孵化。实验结果表明:保存条件对种蛋孵化率起决定性影响,保存期1周内孵化率最佳,超过1周则孵化率明显下降。翻不翻蛋对种蛋孵化率的影响显著,但显著影响早期和中后期胚胎死亡率。放置方式对保存期在10d以内的种蛋受精率、受精蛋孵化率、胚胎早期死亡率、胚胎中后期死亡率没有影响;种蛋保存期超过10d时,锐端向下存放可提高孵化率。 相似文献
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《The Journal of Applied Poultry Research》2014,23(1):1-6
The current experiment was conducted to evaluate the effect of a synbiotic (Biomin Imbo) on intestinal microflora of Ross broiler chickens. A total of 200 male chickens were randomly divided into 20 groups of 10 birds each, kept in 20 pens (1.5 × 1 m each), and fed for 42 d at different synbiotic levels. Treatments included (1) a basal diet without synbiotics (control), (2) a basal diet with synbiotic levels proposed by the manufacturer, (3) a basal diet with synbiotic levels 25% lower than those proposed by the manufacturer, (4) a basal diet with synbiotic levels 50% higher than those proposed by the manufacturer, and (5) a basal diet with synbiotic levels 25% higher than those proposed by the manufacturer. At the end of the 42-d feeding period, 1 bird was randomly selected from each experimental unit, humanely euthanized, and the cecum was removed to measure the microbial population. The cecal contents were collected in discharge containers for microbial cultures, and counts were conducted after microbial culture. The addition of the synbiotic reduced Escherichia coli and total coliform populations in the intestines of broiler chickens. Conversely, different levels of probiotic increased the numbers of lactobacilli in the intestine of broiler chickens. Concentrations of the synbiotic higher than the recommended levels in the diet increased the lactic acid bacteria population in the gut of broiler chickens. 相似文献
157.
Masafumi Katayama Tomokazu Fukuda Toshimitsu Hatabu Kiyoaki Narabara Asaki Abe Yasuhiro Kondo 《Animal Science Journal》2014,85(3):277-285
In chickens, although estrogen receptors (ER) are reported to be associated with the immunological processes, detailed information about the differences in ER expression in the tissues related to the development of lymphocytes is not fully known, especially during the developmental stage. To learn more about this immunological relationship, we used semi‐quantitative polymerase chain reaction method to detect the ER expression levels in the thymus tissues of chicks during the developmental stage. Furthermore, ER‐expressing cells were detected by immunohistochemistry. The results of this study show that the expression level of ER increased on embryonic day 16 and decreased on day 20. Furthermore, ER expression was significantly higher in male than in female chickens at day 16. The increased expression on day 16 and decreased level on day 20 were also reproduced in the incidence of immunoreactive cells, although there was a 1‐day delay in the elevated incidence of the cells. This study revealed the changes in ER expression and the incidence of ER‐positive cells in the thymus of chickens during the developmental stage. 相似文献
158.
Ganzaya Perenlei Hitomi Tojo Toru Okada Masatoshi Kubota Motoni Kadowaki Shinobu Fujimura 《Animal Science Journal》2014,85(10):895-903
We evaluated effects of dietary supplementation with astaxanthin (Ax)‐rich yeast, Phaffia rhodozyma (Xanthophyllomyces dendrorhous), on broiler chicken meat quality. Fourteen‐day‐old female Ross broilers were divided into three groups: control group, Ax‐free diet; Ax 10 group, 10 mg/kg Ax diet; and Ax 20 group, 20 mg/kg Ax diet for 28 days. At 42 days old, chickens were slaughtered, and then growth performance, meat quality and sensory attributes were analyzed. Compared with the control, a* values increased significantly after slaughter and 48 h postmortem for Ax 20 samples (P < 0.05) and for b* values in Ax 20 and Ax 10 groups (P < 0.05). Cooking loss decreased in the Ax 20 group (P < 0.05). After 120 h aging, contents of several free amino acids and total free amino acid content of Ax 20 group were significantly higher than the control (P < 0.05). In sensory evaluation, meat texture attributes improved significantly in the Ax 20 group (P < 0.01). No significant changes occurred in flavor attribute scores of meat soup from the Ax 20 group compared with the control even though most assessors preferred meat soup from the Ax 20 group. Overall, Ax‐rich yeast in the diet improves broiler chicken meat quality. 相似文献
159.
试验采用直接骨髓法制备林芝藏鸡染色体,通过显微自动成像系统观察藏鸡细胞有丝分裂全过程,包括间期、早前期、前期、中期、后期和末期,并分析了藏鸡有丝分裂过程染色体的形态变化规律。通过比较有丝分裂各期的形态,结果发现藏鸡有丝分裂的前期染色体伸展最长,碱基暴露最多,适合于做基因定位工作。同时进行了藏鸡染色体的核型分析,数据统计结果发现林芝地区藏鸡染色体数目2n=78,其中前5对染色体和性染色体中有3对中央着丝粒(m)染色体、1对近中着丝粒(sm)染色体、2对端着丝粒(t)染色体。与前人试验结果进行了比较,结果显示存在一定差异,原因仍需进一步试验验证。 相似文献
160.