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991.
Saki Ishimaru Mabrouk Elsabagh Seiichi Saiki Atsushi Haruno Maki Nakamura Hidetada Funo Taketo Obitsu Izuru Shinzato Toshihisa Sugino 《Animal Science Journal》2019,90(8):932-938
Three rumen‐protected lysine (RPL) products (AjiPro®‐L, LysiPEARLTM, and Feedtech Bypass LysineTM: A, B, and C, respectively) were tested for stability in two forage‐based total mixed rations (TMR1, 41.3% dry matter (DM), and TMR2, 49.5% DM) (experiment 1) and for Brix value (experiment 2). In experiment 1, each RPL product (2 g each) and TMR diet (200 g) were mixed and stored in plastic bags at 20°C for 0, 1, 3, 6, 12, 24, and 48 hr. In experiment 2, each RPL product (2 g) was dispensed into ion‐exchanged water (20 ml) and kept at 20°C for 0, 0.5, 1, 3, 6, 12, 24, and 48 hr. At each time point, free lysine (Lys) content and Brix values of extracts were measured, and Lys release (LR, %) was calculated. All RPL products LR% varied with varying diets DM and increased with increasing of time exposed to diets; it was highest in C, followed by B, and then A. Water LR% positively correlated with that from diets and with Brix values of Lys dissociated in water. Our results indicated that Lys dissociation from RPL products is affected by diet DM content. Brix value may be used as a potential marker for RPL protection efficacy. 相似文献
992.
Geophagy, the ingestion of earth varying in particle size from stones to soils rich in clay, is a relatively widespread behaviour across avian taxa. We reviewed its occurrence in birds and its hypothesised adaptive functions in birds. Of the ~30 avian orders, 23 exhibit geophagy. However, it has only been documented in ~260 species (~2% of birds) and therefor is relatively uncommon. Ingestion of stones and other large particles (grit) is recorded in 54 extant families across the avian phylogeny and appears to be ancient in birds and has evolved several times. Clay ingestion is recorded in 14 phylogenetically scattered families and might have evolved repeatedly. Furthermore, at least nine families exhibit both clay and grit ingestion. Six hypothesised functions of avian geophagy involve digestion and nutrition. Ingested grit might provide (1) essential minerals, particularly sodium or calcium, but it appears to primarily (2) improve mechanical digestion of food in the gizzard, where ingested stones and sand particles are known as gastroliths. Consistent with this gastrolith hypothesis, ~86% of species ingesting grit consume “hard” food: seeds, leaves, insects or other animals. In contrast, ingested clay appears to be for sodium or other nutrient intake and/or protecting birds from ingested plant secondary compounds, by (3) protecting the digestive tract and (4) adsorbing these compounds. Consistent with this, ~88% of species ingesting clay eat fruit that is often rich in secondary compounds and low in sodium, and clay ingestion is associated with frugivory in a representative sample of genera of which many have been shown to source sodium. The other two hypotheses are buffering gastric pH (5) and acquiring antidiarrheal agents (6), but no documentation of this in birds was found. We suggest additional tests of these hypotheses and additional investigation of these proposed benefits of geophagy in birds. 相似文献
993.
The local ecological knowledge (LEK) and perceptions of grasses were investigated in six semi-arid communal areas in the central Eastern Cape province, South Africa, and compared with field studies and scientific knowledge. Of the total of 21 grasses identified in the field survey, communal farmers had vernacular names only for 11 species. Respondents rated Digitaria eriantha and Pennisetum clandestinum to have the highest (p < 0.05) grazing value. Respondents’ ratings of Eragrostis obtusa and Sporobolus africanus as having similar (moderate) grazing values to Themeda triandra is against the established knowledge. Respondents’ ratings of T. triandra and S. africanus as having higher (p = 0.01) ecological value than the other grasses concur with the scientific knowledge, whereas their nomination of E. obtusa and D. eriantha as providing less ecological benefits than Aristida conjesta disagrees with some ecologists. The study hinted at the complementarity and discrepancies between LEK and scientific knowledge that need ratification. The respondents’ lack of detailed knowledge is suggestive of a gradual eroding of LEK among the local communities that will adversely impact the local people’s ability to implement sustainable rangeland utilisation practice. The current study also recognised farmers’ familiarity as well as training needs that would expound their knowledge and management of grasses. 相似文献
994.
This study was aimed to examine the characteristics of three isolated lactic acid bacteria (LAB) strains (HG24, M1, and TG1), and to evaluate their effects on fermentation characteristics, nutritive value, and in vitro digestibility in a variety of substrates. The experiments were conducted with Italian ryegrass (Lolium multiflorum Lam.), tall fescue (Festuca arundinacea Schred.), and oat (Avena sativa L.) in laboratory silo (1 L) for ensiling 30 days. All the treated silages had significantly (p < 0.05) higher in vitro dry matter digestibility (IVDMD), and lower undesirable microorganism populations compared with controls. In Italian ryegrass and oat silages, all the inoculants improved the fermentation quality, evidenced by distinctly (p < 0.05) higher LA contents and ratios of LA to acetic acid, and lower pH, butyric acid and ammonia nitrogen contents. Strains HG24 and commercial inoculant G (Lactobacillus plantarum MTD‐1) performed better than strains M1 and TG1, indicated by obviously (p < 0.05) higher LA contents, LAB numbers, and IVDMD. In tall fescue silage, all the isolated LAB strains (HG24, M1 and TG1) markedly (p < 0.05) increased IVDMD compared with strain G. Strain HG24 is recommended as a good LAB inoculant for ensiling in various forages. 相似文献
995.
动物毛色是一种容易被识别的表型,也可作为筛查某些疾病的有效手段。毛色主要由黑色素细胞产生的真黑色素和棕黑色素的分布、比例和产生速率所决定。许多基因对黑色素的产生和分布起着重要调控作用,各基因间的不同基因型形成多种基本毛色、淡化毛色和花斑。此外,miRNA靶向结合毛色主效基因mRNA,诱导抑制/增强其转录翻译过程,从而调控毛色基因的表达,影响黑色素合成。文章简述了家畜调控毛色的主效基因黑色素皮质素受体1(MC1R)、野灰位点信号蛋白(ASIP)、原癌基因(KIT)、酪氨酸酶关联蛋白(TYRP)、小眼畸形相关转录因子(MITF)和内皮素受体B(EDNRB)的DNA序列多态性(不同基因型)与毛色性状、疾病之间的关系;介绍了毛色形成相关miRNA挖掘鉴定、miRNA调控毛色相关基因研究进展与毛色基因研究应用价值,旨在为今后研究家畜毛色机理提供理论依据。 相似文献
996.
本研究总结了全珠小麦青贮饲料和小麦秸秆青贮饲料的保存和营养特性。选择25包来自4个不同田间的全珠小麦青贮饲料和10包小麦秸秆青贮饲料,分别进行了全株小麦青贮和秸秆青贮试验。全珠小麦青贮饲料保存良好,平均pH值为4.46,乳酸、乙酸和丁酸盐的浓度分别为19.2、10.4和4.7g/kg。小麦秸秆青贮饲料的平均pH值为5.46,由于干物质含量较高,发酵受到抑制,乳酸、乙酸和丁酸盐的浓度分别1.9、2.2和1.0g/kg。全株小麦青贮饲料粗蛋白含量为78g/kg,中性洗涤纤维含量为546g/kg,非纤维碳水化合物含量为306g/kg。全珠小麦青贮饲料中粗蛋白和非纤维碳水化合物含量变化较大,中性洗涤纤维含量变化相对较小,这与籽粒成熟度的差异有关。全株小麦青贮饲料和秸秆青贮饲料的体外有机质降解率分别为56.1%和29.3%。全株小麦青贮饲料的体外有机质降解与pH、乳酸和乙酸盐含量无显著相关性(P>0.05),与丁酸盐含量和氨氮比值有显著相关性的趋势(P=0.07)。瘤胃对全珠小麦青贮饲料的发酵早期体外气体生成的变异系数越高,相对于一些纤维组分,如中性洗涤纤维和酸性洗涤纤维,测定的非纤维碳水化合物变异系数也相应升高。综上所述,冬季旱地栽培的小麦可以作为全株青贮饲料在瘤胃中发酵提供能量,小麦秸秆也可以作为纤维原料进行青贮。 相似文献
997.
为探讨苜蓿干草捆贮藏过程中营养物质含量的动态变化规律,对含水量为15%、打捆密度为150kg/m3的苜蓿草捆在不同贮藏时间(1、10、30、90、180、360d)营养物质含量和相对饲喂价值(RFV)的动态变化情况进行研究。结果表明,在整个贮藏过程中,苜蓿干草的粗蛋白(CP)含量总体呈下降趋势,与贮藏1d时相比,不同贮藏时间段苜蓿干草的CP含量均显著下降(P<0.05);从CP含量角度评价,苜蓿干草等级由1级下降到2级。苜蓿干草的中性洗涤纤维(NDF)含量随贮藏时间的延长而增加,贮藏360d时的NDF含量显著高于贮藏时间在90d之内的NDF含量(P<0.05);从NDF含量角度评价,苜蓿干草等级由2级下降到3级。酸性洗涤纤维(ADF)含量也随贮藏时间的延长而增加,贮藏10d之后ADF含量开始显著增加(P<0.05);从ADF含量角度评价,苜蓿干草等级由1级下降到4级。贮藏时间在30d以上的苜蓿干草DMI值显著低于贮藏时间在30d之内的DMI值(P<0.05);从DMI值角度评价,苜蓿干草等级由1级下降到3级。贮藏时间在90d以上的苜蓿干草DDM值显著低于贮藏时间在90d之内的DDM值(P<0.05);从DDM值角度评价,苜蓿干草等级由1级下降到4级。随着贮藏时间的延长,苜蓿干草的RFV值显著降低(P<0.05),且在贮藏180~360d的时间段内,RFV值下降幅度较大;从RFV值角度评价,苜蓿干草等级由2级下降到3级。综合比较,苜蓿干草在贮藏180d之后营养价值大幅度下降,因此,在贮藏180d之内出售或者饲喂家畜比较适合。 相似文献
998.
通过测定生殖道黏液导电性确定小尾寒羊配种时机的观察研究 《畜牧与饲料科学》2019,40(12):54-57
通过使用羊排卵测定仪准确掌握不同繁殖期小尾寒羊的排卵期,旨在有效提高母羊的受孕率。选择1.5~3.5周岁和4~6周岁小尾寒羊空怀期繁殖母羊各30只,利用羊排卵测定仪测定发情期内母羊生殖道黏液电阻值,研究其变化规律,发现1.5~3.5周岁母羊组发情持续时间较短,电阻值下降和上升均较快;而4~6周岁母羊组发情持续时间较长,电阻值下降较快但其上升曲线较为曲折。比较处于不同阴道黏液电阻值范围的母羊人工授精后的受孕率发现,4~6周岁的羊群组比1.5~3.5周岁的羊群组可受孕范围宽,但1.5~3.5周岁的羊群组在可受孕电阻值范围内受孕率明显高于4~6周岁的羊群组。该研究结果提示,不同年龄小尾寒羊母羊阴道黏液电阻值变化幅度不同,发情周期内电阻值下降到最低点后再上升时期为小尾寒羊的排卵期,适宜配种,该时期为母羊配种受孕率高。 相似文献
999.
我国茶资源丰富,且其富含多种独特的营养成分,可以调节畜禽机体的生理功能,在畜禽养殖应用中无残留、无毒副作用,能从根本上满足人们对畜禽产品品质安全的需求,从而改善和提高人们的生活水平。为此,文章就茶及其副产物的生物学特征和营养水平进行介绍,并综述其作为饲料资源对畜禽自身的生长发育、畜产品品质的影响,以及在畜禽养殖上的保健作用,旨在为茶及其副产物作为新型饲料资源的开发应用提供参考。 相似文献
1000.