不同添加剂对柱花草青贮品质的影响

以热研2号柱花草为原料, 通过直接青贮（CK）、 添加山梨酸（0.2％）、 蔗糖（2％）、 青贮宝（0.1％）等处理, 30 d后测定了柱花草青贮饲料pH值、 乳酸、 乙酸、 丙酸、丁酸等含量并分析其主要营养成分含量。结果表明： 柱花草直接青贮品质较差, 添加山梨酸、 蔗糖、 青贮宝等处理能降低pH值和提高乳酸含量, 添加2％蔗糖能极显著降低pH值(p<0.01)、 提高乳酸含量(p<0.05), 改善青贮品质, 提高营养价值。     

饲料型油菜南种北种产量及品质特征分析

黑龙江省北部是麦豆主产区,存在麦后土地休闲的时间过长、光能和水分浪费严重等现象,本研究选用南方双低饲料油菜1号进行麦后种植,通过田间大区对比试验,分析饲料型油莱和食用型油菜在株高、鲜重、干重、产量及品质指标的差异。结果表明：饲料型油菜株高、鲜重、干重及产量均高于食用型品种,收获时饲料型油菜株高70cm,食用型油菜20．1cm;饲料型油莱每hm2产量82500kg,食用油菜产量37700kg;饲料型油菜粗蛋白、粗脂肪、粗纤维及微量元素（除铁）含量均高于食用型油菜。进一步说明黑龙江省春小麦复种饲料型油菜可行,推广前景可观。     

栽培因子对高油酸油菜品质的影响

以湘油708为材料,设置施肥类型、施肥量和种植密度为栽培因子,利用气相色谱法测定脂肪酸含量,探究栽培因子对高油酸油菜脂肪酸含量的影响.结果表明:不同处理间油菜油酸和芥酸含量均存在显著性差异,施加75 kg/hm^2有机肥、种植密度为45万株/公顷条件下品质最好,油酸含量79.6%、芥酸含量0.058%.本研究证明了适当施肥和合理的种植密度,对油菜品质具有一定调控作用,可为高油酸油菜种植方法提供参考.     

我国饲料油菜种植及应用技术研究进展

随着“粮改饲”政策在我国的逐步推行,饲料油菜在我国西北、东北地区以及长江流域的推广面积逐年增加,越来越受到广大农户和养殖户的认可。本文回顾了饲料油菜在我国的发展历程,总结了饲料油菜的特点,并对饲料油菜品种选育、栽培技术、种植制度、利用方式及饲用效果等方面进行了综述;讨论了我国饲料油菜生产和研究中存在的问题,对饲料油菜的研究内容和发展方向进行了展望。     

不同密度对青贮玉米产量与品质的影响

青贮玉米不同密度下的子粒产量和品质测定结果表明,不同种植密度直接影响子粒的产量与品质,在一定的密度范围内,玉米子粒蛋白质、脂肪的含量在不同成熟阶段随密度的增加呈下降趋势。玉米子粒中蛋白质、脂肪的低含量与最高产量相对应,但玉米子粒中蛋白质、脂肪的高含量却不与较低产量相对应。     

不同水分条件下硼对油菜营养生理的影响

在水培条件下,利用PEG－6000诱导水分胁迫,研究硼对油菜幼苗的萌发及营养生理的影响。萌发试验表明,高浓度PEG（30％）浸种抑制油菜籽的萌发,而低浓度PEG（15％）浸种促进萌发,并可提高幼苗的抗旱性。水培结果指出,干旱胁迫使油菜B浓度下降,油菜保护酶系统中的POD、CAT、SOD等酶活性均下降,MDA含量及膜透性增加,另外,渗透调节物质如Ca^2 、脯氨酸、可溶性糖的含量均大幅度提高,说明B营养在一定程度上可缓妥解干旱对油菜造成的伤害。     

不同青贮方式对菠萝茎叶饲用品质的影响

分析添加尿素和废糖蜜对青贮菠萝茎叶营养成分的影响,并测定青贮后菠萝茎叶养分的瘤胃降解率。为提高菠萝茎叶的饲料化利用提供理论依据。试验以直接青贮菠萝茎叶为对照组,分别添加10 g/kg尿素、20 g/kg废糖蜜、10 g/kg尿素+20 g/kg废糖蜜为试验组,青贮45 d后进行营养成分、养分的瘤胃降解分析。结果表明:与对照组相比,添加10 g/kg尿素青贮菠萝茎叶可以显著降低单宁含量,提高粗蛋白(CP)、氨态氮(NH3-N)含量(p0.05);添加20 g/kg废糖蜜,CP、单宁含量显著提高(p0.05);添加10 g/kg尿素+20 g/kg废糖蜜,CP、NH3含量提高,乙酸含量降低,差异显著(p0.05);3个试验组中,DM、CP、中性洗涤纤维(NDF)在瘤胃内经72 h后的降解率均显著高于对照组(p0.05)。本试验中,添加10 g/kg尿素+20 g/kg废糖蜜可以显著提高青贮菠萝茎叶的品质,并提高青贮菠萝茎叶养分的瘤胃降解率。     

不同栽培措施对青贮玉米产量和营养品质的影响

采用随机区组设计和“3414”最优回归设计,研究青贮玉米不同种植密度、收获期和施肥水平对产量和营养品质的影响。结果表明：不同种植密度、收获期和施肥水平均极显著影响青贮玉米的产量和营养品质。其中,氮肥对青贮玉米的鲜、干生物产量的提高及青贮玉米营养品质、饲用价值的提高贡献最大,其次是磷肥,钾肥的影响较小。建立了氮、磷、钾肥和青贮玉米鲜、干生物产量,蛋白质产量,中、酸性洗涤纤维产量,脂肪产量的回归数学模型。得出了青贮玉米新饲玉14号在海南中等肥力土壤上的适宜种植密度为7.50～9.00万株/hm2;最佳收获期是籽粒乳熟中期; 预测出了获得青贮玉米最大鲜、干生物产量,蛋白质产量,中、酸性洗涤纤维产量,脂肪产量时所需氮、磷、钾肥的施用量。     

播期对青贮大麦产量和青贮品质的影响

为探究新疆北部地区播期对青贮大麦产量、青贮原料品质和青贮品质的影响,以3个大麦品种(系)(垦啤麦13、P13-3和甘啤4号)为材料,分别于3月18日、4月2日、4月17日播种,对其青贮农艺性状、干草产量、青贮原料营养成分和青贮品质进行分析。结果表明,随着播期的推迟,青贮大麦生育期大幅度缩短,4月17日播种时生育期较3月18日缩短22~23 d。晚播会显著降低大麦干草产量,晚播(4月17日)时3个品种(系)干草产量比早播(3月18日)降低15.2%~24.2%,其中垦啤麦13降幅最大。推迟播种使垦啤麦13和甘啤4号茎、穗的干物质分配比例下降,叶的干物质分配比例上升。晚播使P13-3和甘啤4号洗涤纤维含量(中性和酸性)和粗脂肪含量分别显著上升和下降,显著降低P13-3的粗蛋白含量,提高甘啤4号可溶性碳水化合物含量。播期对青贮品质影响因品种(系)而异,晚播降低了甘啤4号青贮的pH值、氨态氮含量,提高乳酸含量,对其他品种(系)无显著性影响。总体来看,新疆青贮大麦在外界条件允许的条件下,应适当早播。     

密度对青贮玉米产量和品质的影响

以4个青贮玉米品种为试验材料,研究了4个种植密度对青贮玉米生物产量、干物质产量和品质的影响。结果表明:不同品种之间生物产量和干物质产量差异极显著;不同密度下品种的生物产量和干物质产量差异极显著;不同密度对不同品种品质影响较大,增加密度有助于青贮玉米品质的提高。青贮玉米品种的生育期、株高、穗位高、茎粗、收获期、绿叶数差异不大,品种间差异主要由品种自身特性决定。     

播期对饲用油菜鲜草产量和品质的调控研究

为确定华北平原饲用油菜高产优质的适宜播期,选用甘蓝型油菜品种4个,设置4个播期,研究不同播期下温度对饲用油菜鲜草产量和饲用品质的调控效应。结果表明,随播期推迟,饲用油菜生育期内日均温与有效积温升高,花前生育期天数缩短但花后生育期延长,总生育期天数缩短2～7 d。饲用油菜鲜草产量随播期推迟呈降低趋势,3月28日前播种超过35 t/hm2;品种间华油杂62鲜草产量显著高于其它品种（P<0.01）。饲用油菜鲜草产量和饲用品质与纤维含量显著负相关,中性洗涤纤维含量与苗期的有效积温量极显著负相关,与营养生长和花后有效积温量显著正相关。因此,在华北平原春播饲用油菜可选用华油杂62,播期以3月8日-3月18日为最佳,鲜草产量稳定在50 t/hm2以上,具有较高的粗蛋白、淀粉、水溶性碳水化合物和总可消化养分含量,可实现华北平原饲用油菜的高产优质生产。     

Separating the effects of forage source and field microbiota on silage fermentation quality and aerobic stability

This study attempted to separate the effects of forage source and field microbiota on silage fermentation quality and aerobic stability. Single samples of grass, red clover and maize were used. Field microbiota was obtained by centrifugation of microbial suspensions of the three samples. The intact forages were dried and sterilized by heating at 60°C for 3 h + 103°C for 15 h, inoculated in a 3 (forage) × 3 (inoculum) design and reconstituted to a dry‐matter level of 400 g kg^?1 before ensiling. After ensiling for 71 d, subsamples were subjected to an 8‐d aerobic stability test, which included temperature and pH measurements. Bacterial community analysis was performed on samples before and after ensiling by 16S rRNA gene amplicon sequencing. Forage source had a marked effect on the levels of lactic acid, acetic acid, ammonia‐N and 2,3‐butanediol, but microbiota source only affected the acetic acid concentration. The forage and microbiota as well as their interactions affected silage stability variables. The maize microbiota improved silage stability, whereas silages made from the maize forage had the poorest stability. Bacterial community analysis revealed higher abundance of lactic acid bacteria on the maize forage, with Lactococcus and Leuconostoc being the dominant genera. These preliminary results suggested that fermentation quality is mainly affected by forage source, whereas the aerobic stability is affected by both forage and field microbiota.     

Fresh and ensiled forage plants—total composition,silage losses and the prediction of silage composition from the crop

Twenty ley and whole‐crop samples were analysed before and after ensiling to determine the proportion of dry matter (DM) that could be accounted for by the sum of 12 chemical assays for ash, ash‐excluded‐amylase‐treated neutral detergent fibre (aNDFom), starch, water‐soluble carbohydrates (WSC), pectin, crude protein (CP), CP in aNDFom (CPndf), ammonia, crude fat, phenolics, plant organic acids and liquid fermentation products (acids and alcohols). Crop components, utilized during silage fermentation and the possibility of predicting silage composition from that of the crop, were also investigated. Samples consisted of timothy and red and white clover, harvested at early and late maturities in two cuts per maturity and of whole‐crop barley, wheat and maize, harvested at early, intermediate and late stages of maturity. Ley crops were wilted to reach a DM content of approximately 400 g/kg, whereas whole crops (WC) were not wilted (151–757 g DM/kg) before ensiling. The average sum of analytes was 1022 and 981 g/kg DM for crops and silages respectively. An overall closeness to complete recovery indicates that no major plant components were missing from the analyses. Relative proportions of pectin, plant organic acids and phenolics, which are rarely analysed, were approximately 60:40:2 (w/w). Ash, aNDFom, crude fat and CP were almost completely recovered after ensiling, whereas partial metabolism reduced recoveries of starch (81%), CPndf (62%), plant organic acids (65%), pectin (64%) and WSC (29%). Only the four analytes with high silage recoveries could be reasonably well predicted from parent crop levels with mean prediction error from 0.065 for aNDFom to 0.167 for crude fat.     

Effects of polyethylene colour and thickness on grass silage quality

The aim of the investigation was to determine the influence of variations in thickness and colour of agricultural plastic film on silage preservation conditions and grass silage quality. For this purpose, 30 cylindrical plastic containers (mini‐silos; 0·3 m³) were filled with chopped grass and covered with five films of different thickness and colour: 90 μm, white; 125 μm, green; 150 μm, black; 200 μm, green and 200 μm, white. Four replications of each film type were placed in the open air. Two replications were housed indoors and exposed to an ‘artificial sky’ in a test apparatus. The surface temperature of the films was found to be strongly dependent on film thickness and colour. Results of the chemical analysis of silages did not reveal any significant influence of the films. This was also the case when restricting the analysis to the uppermost silage layer. The results showed that under the conditions of this experiment, well preserved forage can be produced with films of differing colour, as well as of lesser thickness.     

Effect of chitosan on the preservation quality of sugarcane silage

We aimed to evaluate the effects of chitosan and microbial inoculant addition to sugarcane silage fermentation, gas and effluent losses, chemical composition, in situ dry matter (DM), neutral detergent fibre (NDF) degradation and aerobic stability. A completely randomized design with four treatments (n = 40) was performed. It was arranged in a 2 × 2 factorial scheme with chitosan [0 and 6 g/kg of sugarcane DM—1.66 g/kg of natural matter (NM)] and microbial inoculant (0 and 8 mg/kg on NM). Each g of inoculant contained 3.9 × 10¹⁰ UFC/g of Pediococcus acidilactici and 3.75 × 10¹⁰ UFC/g of Propionibacterium acidicipropionici. The addition of microbial inoculant increased lactic acid concentration in silos treated with chitosan. Furthermore, chitosan increased pH and tended to increase acetic acid of silage. In contrast, the inoculant decreased pH and acetic acid, besides increasing ethanol concentration. As chitosan addition increased DM recovery, inoculant addition decreased it. Chitosan decreased NDF and acid detergent fibre (ADF) level and increased DM degradation, while inoculant decreased DM content, DM and NDF degradation. In addition, chitosan improved the aerobic stability only in non‐inoculated silos. Thus, chitosan has a positive effect on silage fermentation, reducing fermentative losses, and improving silage chemical composition and degradation. Conversely, the addition of microbial inoculant negatively affected silage DM recovery, chemical composition, and its association with chitosan decreased the aerobic stability when compared to the exclusive use of chitosan.     

Effect of forage species and ensiling conditions on silage composition and quality and the feed choice behaviour of goats

The hypothesis was that forage species and ensiling conditions have an impact on the formation of biogenic amines and the feed choice of goats in short‐term preference trials. At ensiling, lucerne (Medicago sativa L., first cut), red clover (Trifolium pratense L., first cut) and Italian ryegrass (Lolium multiflorum Lam ., second cut) were treated differently to obtain a range of fermentation qualities. Six treatments of each forage species were prepared and included different dry‐matter concentrations, chemical and biological silage additives, and additions of soil. Silages were sampled for chemical analyses (proximate constituents, fermentation products and other volatile compounds, crude protein fractions and biogenic amines) and stored anaerobically in vacuum‐sealed plastic bags for use in preference trials (one trial for each forage species) with Saanen‐type wethers (n = 8 or 6). Each possible two‐way combination of the six silage treatments and a standard hay (n = 21 combinations) was offered for ad libitum intake for 3 hr. Data were analysed using multidimensional scaling, analysis of variance and correlation analysis between silage characteristics and dry‐matter intake (DMI). For each forage species, fermentation characteristics and crude protein fractions revealed only small differences among treatments. Although the degree of proteolysis, as measured by non‐protein nitrogen, of all silages was high, biogenic amine and butyric acid concentrations were low. The different treatments apparently had no direct influence on the formation of biogenic amines and feed choice. The preference behaviour within one forage species was strongly divergent, but DMI rankings of the three species were very similar.     

饲料油菜与牧草混合冬播效应研究

为缓解冬季饲料作物缺乏的压力,改进冬季饲草的生产模式,提高饲草油菜的品质和种植效益,通过设置小区试验,将双低甘蓝型油菜（Brassica napus L.）分别与紫云英、黑麦草和光叶苕子等冬季牧草按比例混播,测定各处理的生物学产量、粗蛋白含量等指标,探寻油菜与牧草混播技术的可行性。结果表明,油菜与光叶苕子、紫云英、黑麦草的混播效应存在显著差异。（1）光叶苕子与油菜混播均可以提高饲草的鲜样总产量,且在密度按1:4（油菜按15 000株/hm2的播种量）混播时,各取样时期的饲料鲜、干样产量均较高,油菜终花期时该处理的粗蛋白产量显著高于其他处理。（2）与紫云英混播,也可提高饲料油菜的鲜样产量,但差异不显著,且紫云英因光照不足,油菜初花期时已全部死亡。（3）与黑麦草混播后,饲料鲜样产量、粗蛋白产量均显著下降。因此,油菜与光叶苕子混播是进一步提高长江流域冬季饲料作物生产效应的有效模式。     

Effects of incorporating cowpea in a subtropical grass pasture on forage production and quality and the performance of cows and calves

The increasing cost of N fertilizer has stimulated an interest in sourcing protein from warm‐season legumes among beef cattle producers in the tropical/subtropical areas of the world. The objective of this study was to evaluate effects of two strategies of incorporating cowpea [Vigna unguiculata (L.) Walp.] into bahiagrass (Paspalum notatum Flügge) pastures on the herbage characteristics and performance of grazing cow–calf pairs. The study was conducted in Ona, Florida, USA, from May to August in 2007 and 2008. Experimental units were 1·0 ha. Treatments were bahiagrass pasture alone (control), 50:50 bahiagrass–cowpea pasture (cowpea), bahiagrass pasture with a cowpea creep grazing area (0·1 ha, creep grazing) and bahiagrass pasture with a creep‐fed concentrate [(creep feeding; 10 g kg^?1 body weight (BW)]. The cowpea pastures had lower herbage mass [HM, 1·8 vs. 3·7 t ha^?1] and herbage allowance [HA, 0·8 vs. 1·4 kg DM kg^?1 live weight (LW)] compared with the other treatments. Cowpea had greater CP (CP, 160 g kg^?1) and in vitro digestible organic matter (IVDOM), (600 g kg^?1) than bahiagrass (110 and 490 g kg^?1 respectively); however, cowpea HM was only 0·9 t ha^?1 in May and 0·7 t ha^?1 in June, but it did not persist in July and August. Calves receiving the creep feeding treatments had greater average daily gain (0·8 vs. 0·7 kg d^?1) than calves in other treatments. Further research is necessary to exploit the superior nutritive value of cowpea in grazing systems in the south‐eastern USA.     

Effects of an indigenous and a commercial Lactobacillus buchneri strain on quality of sugar cane silage

The aim was to evaluate the effects of adding a novel Lactobacillus buchneri strain and a commercial inoculant on the fermentation and aerobic stability of sugar cane silages (Saccharum spp.). In the first experiment samples were collected from sugar cane silage at 5, 20, 40 and 80 d after ensilage in experimental silos and microorganisms belonging to the Lactobacillus genus were isolated and identified, with a wild strain of L. buchneri, UFLA SIL 72, being selected as an inoculant. In the second experiment sugar cane was inoculated with either the novel bacteria or a commercial inoculant at the moment of ensiling and compared with a control silage prepared without an inoculant. Experimental silos were opened at 0, 3, 10, 30, 60 and 90 d of ensilage and their chemical composition measured. The silages opened after 90 d were also assessed for aerobic stability. The addition of L. buchneri resulted in a higher concentration of acetic acid and reduced populations of yeasts in silage compared to the other silage treatments, and a lower ethanol concentration in the silage. The novel L. buchneri isolate and the commercial inoculant also improved aerobic stability of the sugar cane silages. It was concluded that the addition of the novel inoculants L. buchneri UFLA SIL 72 to sugar cane silage can be recommended.     

黑龙江省饲料油菜品种筛选与种植技术研究

为筛选适宜在黑龙江省规模化种植的饲料油菜品种及栽培模式,采用多年多点的田间定位方法,研究了不同品种、不同种植方式和播期的产量差异和施肥效应以及不同收获期产量及营养成分积累规律。结果表明：金油158、15-P15和12-P38的产量表现好;采用机播平作,播种量15 kg/hm2,底肥施二铵150 kg/hm2,4月22日早播,能够显著提高饲用油菜的生物量。盛花期收获,饲用油菜生物量相对较高,与玉米秸秆混合青贮,制成配合饲料较好。本文结果为饲料油菜在我国北方早熟区开展多功能开发利用提供了参考。