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51.
经过2006-2008年为期3年在硒钴缺乏的河南省郑州市黄河滩区苜蓿(Medicago sativa L.)草地上基施硒钴配合肥料,研究对其生产性能的影响,以期改善苜蓿生长环境和提高苜蓿产量和品质。结果表明,硒钴配合基施均能够显著提高现蕾到开花期苜蓿叶面积指数和净光合能力(P<0.05),提高苜蓿单位叶面积生产干物质的速率,有利于苜蓿的花前青干草生产;在4种硒钴配施肥中,以硒量570 g/hm2、钴量762 g/hm2配施效果最显著,2年内牧草平均增产8.0%(P<0.05),种子的千粒重提高了12.5%(P<0.01),耕作层地下生物量提高了4.6%。 相似文献
52.
Cláudio Eduardo Silva Freitas Eduardo Robson Duarte Dorismar David Alves Isabel Martinele Marta D’Agosto Franciane Cedrola Angélica Alves de Moura Freitas Franklin Delano dos Santos Soares Makenzi Beltran 《Tropical animal health and production》2017,49(4):807-812
A ciliate protozoa suppression can reduce methane production increasing the energy efficiency utilization by ruminants. The physicochemical characteristics of rumen fluid and the profile of the rumen protozoa populations were evaluated for sheep fed banana leaf hay in replacement of the Cynodon dactylon cv. vaqueiro hay. A total of 30 male sheep were raised in intensive system during 15 days of adaptation and 63 days of experimental period. The animals were distributed in a completely randomized design that included six replicates of five treatments with replacement levels (0, 25, 50, 75, and 100%) of the grass vaquero for the banana leaf hay. Samples of fluid were collected directly from the rumen with sterile catheters. Color, odor, viscosity, and the methylene blue reduction potential (MBRP) were evaluated and pH estimated using a digital potentiometer. After decimal dilutions, counts of genus protozoa were performed in Sedgewick Rafter chambers. The averages of pH, MBRP, color, odor, and viscosity were not influenced by the inclusion of the banana leaf hay. However, the total number of protozoa and Entodinium spp. population significantly decreased at 75 and 100% inclusions of banana leaf hay as roughage. 相似文献
53.
U.S Salisu C.A Kudi J.O.O. Bale M Babashani B.Y Kaltungo S.N.A Saidu A Asambe A.Y Baba 《Tropical animal health and production》2017,49(5):1041-1046
A cross-sectional study was carried out to determine the status of Brucella infection in one-humped (Dromedary) camels in the North and Central senatorial districts of Katsina State, Nigeria. Nine hundred and eighty serum samples from live and slaughtered camels were tested. Modified Rose Bengal plate test (RBPT) and serum agglutination test (SAT) with ethylenediaminetetraacetic acid, (EDTA) were used as screening and standard tests, respectively. The prevalence of Brucella antibodies were 110 (11.2%) and 103 (10.5%) for RBPT and SAT, respectively. Of the 472 and 508 serum samples tested from the herds and abattoirs, respectively, 63 (13.3%) and 47 (9.3%) were positive by RBPT while 62 (13.1%) and 41 (8.1%) were positive by SAT, respectively. Based on the results, it was concluded that Brucella antibodies were present in camels in the study area. Poor management practices and mixing of camels with other species of livestock as well as unrestricted movement of camels were proposed to be the reasons for the prevalence of the disease in the study area. In view of the public health importance of the disease, it is recommended that there is the need to develop a strategic plan to decrease spread of brucellosis in the study area. 相似文献
54.
不同的干燥工艺对荷花蜂花粉功能成分的影响 总被引:1,自引:0,他引:1
探讨了5种干燥工艺对荷花蜂花粉功能成分的影响。微波干燥的干燥效率最高,60%火力处理540s可使水分从31.41%降到6.42%;干燥方式对荷花蜂花粉蛋白质影响较小;微波干燥后总黄酮提取率最高,为13.20mg/g;真空冷冻干燥后维生素C和过氧化氢酶含量最高,分别为48.89mg/100g和29.86mg/g·min。总的来说,真空冷冻干燥对荷花蜂花粉的功能成分影响最小;常压恒温干燥对功能成分影响较小、工艺简单、对设备要求低,宜于大规模应用于实际生产中。 相似文献
55.
56.
Hiskett EK Suwitheechon OU Lindbloom-Hawley S Boyle DL Schermerhorn T 《Veterinary research communications》2009,33(3):227-240
In most mammals, glucokinase (GK) acts as a hepatic “glucose sensor” that permits hepatic metabolism to respond appropriately
to changes in plasma glucose concentrations. GK activity is potently regulated by the glucokinase regulatory protein (GKRP),
which is encoded by the GCKR gene. GKRP binds GK in the nucleus and inhibits its activity. GK becomes active when it is released from GKRP and translocates
to the cytosol. Low glucokinase (GK) activity is reported to be a principal feature of feline hepatic carbohydrate metabolism
but the molecular pathways that regulate GK activity are not known. This study examined the hypothesis that species-specific
differences in GKRP expression parallel the low GK activity observed in feline liver. Hepatic GKRP expression was examined
using RT-PCR, immunoblot, and confocal immunomicroscopy. The results show that the GCKR gene is present in the feline genome but GCKR mRNA and the GKRP protein were absent in feline liver. The lack of GKRP expression in feline liver indicates that the low
GK activity cannot be the result of GKRP-mediated inhibition of the GK enzyme. However, the absence of the permissive effects
of GCKR expression on GK expression and activity may contribute to reduced GK enzyme activity in feline liver. The study results
show that the cat is a natural model for GCKR knockout and may be useful to study regulation of GCKR expression and its role in hepatic glucose-sensing and carbohydrate metabolism. 相似文献
57.
本试验旨在研究饲料脂肪水平对白甲鱼幼鱼生长性能、体组成及血清生化指标的影响。选用初始体质量为(0.78±0.05)g的白甲鱼幼鱼900尾,随机分成6组(每组3个重复,每个重复50尾),分别饲喂豆油添加水平为0(对照组)、2%、4%、6%、8%和10%(实测脂肪水平为2.83%、4.52%、6.68%、9.14%、11.35%和14.07%)的试验饲料,养殖期为60 d。结果表明:随饲料脂肪水平的升高,白甲鱼幼鱼的增重率(WGR)、特定生长率(SGR)、蛋白质效率(PER)均呈现先上升后下降的趋势,饲料系数(FCR)呈现先下降后上升的趋势。饲料脂肪水平为11.35%时WGR、SGR达到最大(分别为362.98%和3.06%/d),显著高于除6.68%和9.14%组之外的其他各组(P<0.05);饲料脂肪水平为9.14%时PER达到最大(3.70%),而FCR达到最小(1.34),显著高于/低于除11.35%组之外的其他各组(P<0.05)。白甲鱼幼鱼的肝体比则随饲料脂肪水平的升高而上升,6.68%、9.14%、11.35%和14.07%组均显著高于对照组(P<0.05)。各组白甲鱼幼鱼的脏体比无显著差异(P>0.05)。通过二次回归分析可知,白甲鱼幼鱼WGR、SGR、FCR及PER最优时,饲料脂肪水平分别为10.12%、9.56%、9.42%和10.18%。随着饲料脂肪水平的升高,白甲鱼幼鱼全鱼及肌肉粗脂肪含量逐渐升高,而全鱼及肌肉粗蛋白质含量则呈先升后降的变化趋势。饲料脂肪水平对白甲鱼幼鱼全鱼及肌肉水分和粗灰分含量无显著影响(P>0.05)。随着饲料脂肪水平的升高,白甲鱼幼鱼的血清胆固醇(CHO)和甘油三酯(TG)含量先升高后降低,高密度脂蛋白胆固醇(HDL-C)和胆汁酸(TBA)含量以及谷丙转氨酶(ALT)、谷草转氨酶(AST)和碱性磷酸酶(ALP)活性逐渐升高,而低密度脂蛋白胆固醇(LDL-C)含量则逐渐降低。饲料脂肪水平为9.14%时,血清CHO含量达到最高,且与其他各组差异显著(P<0.05);饲料脂肪水平为11.35%时,血清TG含量达到最高,且与其他各组差异显著(P<0.05)。由此得出,适宜的饲料脂肪水平可促进白甲鱼幼鱼的生长,提高其饲料转化率和免疫能力;饲料脂肪水平过高则可引起其肝损伤或组织病变。在本试验条件下,综合考虑生长性能、体组成及血清生化指标,白甲鱼幼鱼饲料中适宜的脂肪水平为9.42%~10.18%。 相似文献
58.
文章介绍了广东省家禽业生产形势,详细分析了当前家禽市场低迷的原因,并对业界人士关心的今后广东省家禽业生产的趋势、市场形势和发展对策进行研究探析,指出广东省家禽业需要调整结构、凸显品牌、拓展市场、增长效益来提高生产效益。 相似文献
59.
Gerardo Ordaz-Ochoa Aureliano Juárez-Caratachea Rosa Elena Pérez-Sánchez Rafael María Román-Bravo Ruy Ortiz-Rodríguez 《Tropical animal health and production》2017,49(5):1025-1033
The effect of spineless cactus intake (Opuntia ficus-indica) on blood glucose (BG) levels in lactating sows and its impact on daily and total feed intake (dFI?1 and TFI, respectively), body weight loss (BWL), and weaning-estrus interval length (WEI) were evaluated. Thirty-four hybrid (Yorkshire × Landrace × Pietrain) sows in lactation phase were used. Sows were divided into two groups: G1 (n = 17) where they received commercial feed and G2 (n = 17) provided with commercial feed plus an average of 2.0 ± 0.5 kg spineless cactus, based on a sow’s body weight. The variables evaluated were BG, dFI?1, TFI, BWL, and WEI. Statistical analysis was performed by using a fixed and mixed model methodology, under a repeated measurements experiment. Group effects were found on all analyzed variables (P < 0.05). The BG was lower in G2 (55.2 and 64.5 mg/dL pre- and post-prandial, respectively), compared to that in G1 (70.9 and 80.1 mg/dL pre- and post-prandial, respectively) (P < 0.05). G2 showed better performance than G1 for dFI?1, BWL, and WEI (P < 0.05) whose averages were 5.5 ± 1.8 kg, 7.4 ± 4.5%, and 5.3 ± 1.2 days, respectively. Averages for these variables in G1 were 4.7 ± 1.5 kg, 16.8 ± 4.6%, and 6.1 ± 1.6 days, respectively. Intake of spineless cactus reduced BG levels in lactating sows, generating greater dFI?1, lower BWL at the end of lactation, and a lower WEI. 相似文献
60.