Mixtures of clovers with plantain and chicory improve lamb production performance compared to a ryegrass–white clover sward in the late spring and early summer period

A research programme was undertaken over two consecutive years with the purpose of studying the effect of herb–clover swards on lamb production performance year‐round. The focus of this study was on two consecutive late spring and early summer periods (2011, 2012). In each year, three sward treatments were compared on grazed paddocks with 40 lambs ha^?1: (i) grass–clover mixture (perennial ryegrass [Lolium perenne L.] and white clover [Trifolium repens]); (ii) plantain–clover mixture (plantain [Plantago lanceolata], white clover and red clover [Trifolium pratense]); and (iii) chicory–plantain–clover mixture (plantain, chicory [Cichorium intybus L.] and white and red clovers). Lambs were weighed at 2‐week intervals, and carcass weights and GR tissue depth measurements were obtained at slaughter. In both years, lambs on treatments (ii) and (iii) had greater (P < 0·05) final live weight, liveweight gain, carcass weight, dressing‐out percentage and GR tissue depth measurements, and lower feed conversion ratio compared to lambs on treatment (i). Lamb production was similar in treatments (ii) and (iii) (P > 0·05) in each year. Therefore, during the late spring and early summer period, herb–clover mixture swards were found to be a superior option to perennial ryegrass–white clover for finishing lambs.     

Variation in rate of phenological development and morphology between red clover varieties: Implications for clover proportion and feed quality in mixed swards

Red clover (Trifolium pratense) grown in mixtures with grasses often constitutes a lower proportion of total yield in spring than in summer growth. A more even red clover proportion between the harvests would benefit forage quality and management at feeding. We investigated whether inclusion of early versus late‐maturing red clover varieties could reduce this disproportionality. In a two‐year field trial harvested three times per season, each of six red clover varieties was grown in two grass mixtures. Rate of phenological development did not differ during spring growth, but did so in regrowth after first and second cuts. Here, the earliest varieties constituted the highest proportion. At all harvests, the early varieties had lower crude protein concentrations and a higher content of neutral detergent fibre (NDF) and indigestible NDF than the late varieties. Clover proportion was higher in swards with a mixture of timothy and meadow fescue than in swards with perennial ryegrass during the first year and lower in the second year. It is concluded that developmental rate should be explored further as a key character for red clover competiveness in spring growth of rapidly elongating grasses.     

Identification,ecological evaluation and phylogenetic analysis of non‐symbiotic endophytic fungi colonizing timothy grass and perennial ryegrass grown in adjacent plots

Non‐systemic endophytes coexist with grasses and produce positive or negative effects for the host. In agricultural grasses, endophytes such as Epichloë spp. (formerly: Neotyphodium spp.) enhance the biometric parameters and agricultural value of grass biomass and seeds. Some endophytic fungi produce active substances that exert a negative influence on grass‐fed livestock. There is a general scarcity of studies investigating other endophytic fungi, the species composition of fungal communities, fungal species capable of colonizing different grasses and endophyte transfer between grass taxa. This study aims to fill in the existing knowledge gap by describing the relationships between fungal species and grass species. Timothy grass (Phleum pratense L.) is more readily colonized by endophytic fungi than perennial ryegrass (Lolium perenne L.), and the ratio of fungi isolated from the above species was determined at 3:1. Ecological indicators, especially diversity, were also higher in the fungal community colonizing timothy grass. The vast majority of the isolated fungi were ascomycetes. In addition, two Basidiomycota isolates and three Oomycota isolates (Phythium acanthicum) were also obtained from timothy grass. The most prevalent fungal species were Alternaria alternata, Microdochium bolleyi and Epicoccum nigrum. An analysis of minisatellite DNA regions revealed high levels of genetic polymorphism in A. alternata, whereas the remaining isolates were characterized by low levels of genetic variation or genetic homogeneity. The transfer of endophytic fungi between grass species was determined, which was one of the most important observations made in the study. The Sørensen–Dice coefficient reached 50%, which indicates that all fungal species isolated from perennial ryegrass are capable of colonizing timothy grass.     

Production performance and meat quality of grazing lambs finished on red clover, lucerne or perennial ryegrass swards

The combined benefits of a high crude protein concentration, and possible protein protection and growth‐promoting properties, make forage legumes potentially attractive as a natural means of increasing liveweight gain and time to slaughter of lambs in lamb finishing systems. An experiment was conducted to compare the production performance and meat quality of grazing lambs finished on red clover (Trifolium pratense), lucerne (Medicago sativa) or perennial ryegrass (Lolium perenne) swards. Replicate (n = 2) swards of red clover, lucerne and perennial ryegrass were rotationally grazed by ten ram lambs and ten ewe lambs from weaning until selection for slaughter at UK fat class 3L. Lambs grazing the red clover sward had a significantly higher liveweight gain and required significantly fewer days to slaughter than lambs grazing the lucerne sward (305 g d^?1 vs. 243 g d^?1; 38 d vs. 50 d), which in turn had a higher liveweight gain and required fewer days to slaughter than lambs grazing the perennial ryegrass sward (184 g d^?1; 66 d). Lambs grazing the red clover and lucerne swards had significantly higher herbage intakes than those grazing the perennial ryegrass sward (2·06, 1·72 and 1·16 kg DM d^?1 respectively), but in vivo digestibility of herbage was similar. Lambs grazing the red clover and lucerne swards also had significantly higher serum urea concentrations than those grazing ryegrass (12·5, 11·1 and 6·2 mmol L^?1 respectively). Killing‐out percentage was significantly higher for lambs grazing the red clover sward than for lambs grazing the perennial ryegrass sward (48% vs. 46%). There were no significant effects of finishing system on meat flavour, but meat from lambs finished on the lucerne sward was oxidatively less stable than that from lambs finished on the perennial ryegrass sward. Grazing the forage legume swards significantly increased the proportion of linoleic and linolenic acid in muscle tissue, and therefore the proportion of unsaturated to saturated fatty acids (0·19, 0·16 and 0·12 for the red clover, lucerne and perennial ryegrass swards respectively). However, the n?6/n?3 ratio was significantly lower for the muscle of lambs grazing the perennial ryegrass sward compared with those grazing the forage legume swards (1·13, 1·08 and 0·98 for the red clover, lucerne and perennial ryegrass swards respectively). The results indicate that by grazing lambs on forage legume swards it is possible to increase individual lamb performance without compromising meat quality.     

Effect of increasing plant maturity in timothy‐dominated grass silage on the performance of growing/finishing Norwegian Red bulls

An investigation was made of the potential for attaining high daily live weight (LW) gain, high feeding efficiency and carcass quality in Norwegian Red (NRF) bulls fed grass silage harvested at early stages of maturity, supplemented with minimal amounts of concentrates. Roundbale silage was produced from timothy‐dominated swards harvested at three stages of maturity: stages 1 and 2 were dominated by tillers in stem elongation with two and three visible nodes, respectively, and stage 3 by tillers at early heading, with visible heads, but without head stems. Crops were wilted rapidly and a formic acid‐based additive applied. All silages were preserved with restricted fermentation. Silage DOMD values were 0·747, 0·708 and 0·647 for harvesting time (H) 1, 2 and 3 respectively. Silages were fed ad libitum as sole feed, or supplemented with 2–4 kg concentrate at increasing LW, to six bulls per treatment from age 7 months (288 kg) to slaughter at 575 kg. Daily LW gain for bulls fed unsupplemented silage was 1423, 1262 and 936 g, respectively, for H1, H2 and H3, and 1570, 1567 and 1357 g for supplemented bulls. For concentrate‐supplemented bulls, higher energy intake increased proportions of carcass fat more for H1 (0·163) than for H2 (0·134) but the same amount of energy was retained in the carcass per MJ net energy growth intake for these two groups. It is concluded that, apart from milk and concentrate fed to calves during the first months, an intensive beef production with NRF bulls finished before 15 months of age may be based entirely on local grass resources.     

Effects of harvest date of timothy (Phleum pratense) on its nutritive value, and on the voluntary silage intake and liveweight gain of lambs

The effects of harvest date of timothy on the chemical composition of herbage and silage, and on the voluntary intake, liveweight gain and feed conversion efficiency by finishing lambs, were evaluated. The herbage was harvested and ensiled on three dates: 16 June (before heading), 20 June and 26 June. The silages were analysed for chemical composition and degradation characteristics by an in vitro gas production (GP) technique with end-point measurements (72 h) of degradability of organic matter (OM) and neutral-detergent fibre (NDF). There were clear effects of later dates of harvest increasing the concentration of NDF, and reducing the degradability of OM and NDF, and the rate of GP, of silages made from this herbage. The silages were fed ad libitum to lambs in a feeding experiment using a Latin square design. Later harvest dates decreased the voluntary intake of silage, liveweight gain and feed conversion efficiency. Lambs fed the early-cut silage had a liveweight gain of 152 g d⁻¹ and those fed the silage harvested 10 d later had a liveweight gain of 76 g d⁻¹. Changes in the chemical composition of herbage and silage and in in vitro degradation characteristics of silages with later harvests were associated, to a large extent, with the reduction in voluntary intake and liveweight gain of lambs.     

Effects of different additives on fermentation quality and aerobic stability of Leymus chinensis silage

This study investigated the effects of different additives on fermentation quality and aerobic stability of Leymus chinensis silage. Treatments included (i) no additive, (ii) 3 mL kg^?1 formic acid (FA), (iii) 6 mL kg^?1 FA, (iv) 5 mL kg^?1 acetic acid (AA), (v) 10 mL kg^?1 AA, (vi) 2 mL kg^?1 propionic acid (PA), (vii) 4 mL kg^?1 PA, (viii) 5 mL kg^?1 butyric acid (BA), (ix) 10 mL kg^?1 BA, (x) 1.0 g kg^?1 potassium sorbate (PS), (xi) 1.0 g kg^?1 sodium benzoate (SB), (xii) 1 × 10⁸ colony‐forming units (cfu) kg^?1 Lactobacillus (Lb) plantarum LP (LP), (xiii) 1 × 10⁸ cfu kg^?1 Lb. brevis LB (LB) and (xiv) 1 × 10⁸ cfu kg^?1 Lb. buchneri NCIMB40788 (Fresh). Each additive treatment was based on fresh matter (FM). Results showed that all additives decreased pH values. All additives except Fresh decreased ammonia‐N content (p < .001). Both LP and LB increased lactic acid content (p < .001). Butyric acid content increased with FA (3 mL kg^?1) and BA, but decreased with PA, PS, SB, FA (6 mL kg^?1), AA, LP, LB (p < .001). FA (3 mL kg^?1), AA (10 mL kg^?1), PA, BA, PS, SB and Fresh improved aerobic stability (p < .001). After 8 days exposure to air, the pH value and yeast count were lower in FA (3 mL kg^?1), BA (10 mL kg^?1), SB treatments than in other treatments. Overall, AA outperformed all other additives in improving fermentation quality. Sodium benzoate and AA could be used as an effective additive to improve aerobic stability of L. chinensis silage.     

Influence of boron on seed yield and seed quality of organic white clover (Trifolium repens L.)

The effects of boron (B) application on flower development, nectar production, germination and seed yield were investigated in organic seed crops of white clover grown in soils with <1 mg B kg^?1. Application techniques of a liquid B product were studied in two field experiments in 2009–2011. Three rates of B application to the soil at sowing and three rates of B as a foliar application in the harvest year were compared with untreated control plots. None of the B treatments had a significant effect on seed yield, relative to the control. In one experiment, with a dense crop stand, the results indicated a small (10%) yield increase with B applied to the soil. Seed germination and B concentration of shoots, roots and seeds were unaffected by B application, although the soil concentration increased. In seeds with an average B concentration of 22 mg kg^?1, 73% germinated as normal seedlings and 14% were assessed as hard seeds; corresponding values for seeds with an average B concentration of 17 mg kg^?1 were 60 and 38% respectively. The results indicate the need for further studies of factors determining B uptake in white clover .     

Tillage effects,soil quality and production potential of kikuyu–ryegrass pastures in South Africa

Soil quality of tillage systems receives much attention worldwide, although few studies attempt to link soil quality to yield. Partial least‐squares regression analysis is a suitable method to construct predictive models around plural, highly collinear factors, such as soil quality and its effects on yield. This study aimed at identifying the soil quality properties which best model pasture herbage yield by relating soil quality indicators with variations in yield as a result of soil disturbance caused by tillage. The study was conducted on kikuyu (Pennisetum clandestinum) over‐sown with annual ryegrass (Lolium multiflorum) using different tillage methods. Tillage methods involved over‐sowing kikuyu with ryegrass using a minimum‐tillage seed drill, eradication of kikuyu with herbicide and ryegrass sown with a minimum‐tillage planter, shallow and deep disturbance, and a control. Most changes in soil quality indicators as a result of soil tillage were observed shortly after tillage and occurred mostly at the 0–100 mm soil layer. Few of these effects were still visible 420 d after tillage. Microbiological indicators changed most in response to the treatments, but unlike the chemical and physical indicators, microbiological indicators have no causal link to pasture production. The contribution of individual soil quality indicators to variance in pasture productivity could not be isolated and should thus be seen as complex processes which affect yield. Although mechanisms of how some soil quality indicators affect yield is clear, more research is required to determine mechanisms of how a combination of multiple soil quality indicators affects yield.     

播期对花生农艺性状、产量和品质的影响

以普通花生品种（冀花9号、冀花10号、冀花12号）、高油酸花生品种（冀花11号、冀花13号、冀花16号）为材料,通过田间小区试验,设置7个播种时期（4/25、5/6、5/16、5/26、6/6、6/15、6/26）,研究不同播期对花生生长发育、产量指标和品质的影响,以期确定花生最佳播种时期,为集成优质高效栽培技术奠定基础。结果表明,冀花10号、冀花12号、冀花13号、冀花16号的农艺性状表现为主茎高、侧枝长、分枝数多;而冀花9号和冀花11号则表现为主茎矮、侧枝短、分枝少。6个花生品种荚果平均产量为4716.22 kg/hm2,籽仁平均产量为3469.52 kg/hm2。以籽仁产量最高的冀花12号（3541.99 kg/hm2）为对照,普通花生品种冀花9号、冀花10号减产0.35%~1.91%;高油酸花生品种冀花11号、冀花13号、冀花16号减产2.11%~5.54%。随播期的延后,各个播期的花生农艺性状及产量指标基本遵循5/6-5/16 > 4/25 > 5/26-6/26的变化趋势。5/6-5/16播期的平均荚果产量和籽仁产量分别5547.16 kg/hm2、4204.24 kg/hm2,油酸/亚油酸比值平均12.90。4/25播种,荚果和籽仁减产约5.16%,油亚比为14.61;5/26日播种,荚果和籽仁减产约9.05%,油亚比降低35.56%。晚于5/26播种,主茎高变矮7.40%～22.89%、侧枝长变短7.07%～24.89%、单株分枝数减少3.74%～9.70%、单株结果数降低4.59%～21.78%、百果重减少6.59%～27.94%、百仁重减少10.35%～32.33%、荚果减产17.97%～45.78%、籽仁减产21.80%～52.50%、油亚比降低50.57%～73.30%。综合考虑农艺性状、产量指标及品质优劣,河北省中南部地区露地平播花生的最适播期为5/6至5/16之间,最晚不应晚于5/26。     

Effects of Lactobacillus buchneri isolated from tropical maize silage on fermentation and aerobic stability of maize and sugarcane silages

This study was aimed to perform a screening of Lactobacillus buchneri strains from maize silage and use them as inoculant in maize and sugarcane silages. In all, 151 lactic acid bacteria (LAB) strains were isolated from whole‐plant maize silage, and their identification was based on the sequence analysis of 16S rDNA. In total, 15 strains were categorized to the L. buchneri group and eight of these were selected based on growth rate and fermentation pattern. The selected strains were evaluated on fermentation and aerobic stability of maize and sugarcane silages. For maize, the inoculated silages had lower pH and higher LAB population, but lower acetic acid concentration in comparison with the untreated control silage. For sugarcane silage, the strains 56.1, 56.4 and 40788 resulted in highest dry‐matter (DM) content and lowest DM losses. However, only the strain 40788 showed lowest counts of yeasts and moulds. Sugarcane silages inoculated with the strains 56.9, 56.26 and the untreated control silage showed highest concentrations of lactic acid and ethanol, besides the great DM losses. Even so, for both crops, the aerobic stability was not affected by inoculation. After air exposure, all silages increased temperature and had high population of yeast and moulds. Nevertheless, the strains 56.1 and 56.4 are promising for use as a silage inoculant.     

A review of our current understanding of parasite survival in silage and stored forages,with a focus on Fasciola hepatica metacercariae

Fasciola hepatica, the parasitic liver fluke, is a re‐emerging zoonotic infection and an important cause of morbidity and mortality in ruminant livestock worldwide. A significant animal welfare concern, fasciolosis also has a detrimental impact on food security, with the effects of sub‐clinical infection on growth rate and milk yield estimated to cost the UK cattle industry £40.4 million annually. It is understood that up to 50% of infective F. hepatica metacercariae may overwinter on pasture and remain viable to infect grazing livestock the following spring. However, the infection risk posed by feeding grass silage to livestock remains largely unknown as the majority of previous studies are outdated in both experimental design and analysis of ensiled metacercariae viability. Anecdotal reports of fasciolosis outbreaks in housed livestock have reignited interest in F. hepatica metacercariae survival during modern ensiling processes and more importantly if they retain viability within stored forages. Consequently, a comprehensive review of the available literature is required in order to identify knowledge gaps and highlight future research opportunities regarding the role of silage in the transmission of F. hepatica.     

Effects of plant architecture and drought stress level on lucerne forage quality

Breeding for enhanced quality in lucerne (Medicago sativa) frequently involves selection for higher leaf‐to‐stem ratio, multifoliolate leaves or short‐internode stems. Three populations selected for such alternative morphologies and a reference cultivar were evaluated for forage yield, leaf‐to‐stem ratio and protein and fibre concentrations in leaves, stems and whole plants. Four managed environments were obtained by combining two stress levels (moderate or nil) with two sowing times. The population selected for high leaf‐to‐stem ratio, as well as the short‐internode population, had highest leaf‐to‐stem ratio (1.27) across six harvests in two non‐stress environments. The latter population had higher stem protein (12.9%) and lower stem neutral‐detergent fibre (NDF) concentration (58.7%) than other populations. The multifoliolate population had intermediate quality, showing low expression of the multifoliolate trait (14.0% across four environments), particularly under stress (10.5%). The autumn‐sown, fully irrigated environment had, on average, highest dry‐matter yield (4.19 t ha^?1) and lowest leaf‐to‐stem ratio (0.74). Drought‐stressed environments had lower plant NDF (?12.3% on average) and leaf protein (?9.7%), and higher stem protein (+8.6%) than fully irrigated environments. The results suggested that environmental effects might have greater impact on quality than genetic effects, even for a population set including material selected for quality‐driven morphology.     

Effects of ethanol,molasses and Lactobacillus plantarum on fermentation characteristics and aerobic stability of total mixed ration silages

This study was conducted to evaluate the effects of Lactobacillus plantarum, molasses and/or ethanol on fermentation quality and aerobic stability of total mixed ration (TMR) silage, which is widely used in dairy cow diets at mid‐to‐late lactation in Tibet. TMR was treated with ethanol (E), molasses (M), Lactobacillus plantarum(L), ethanol+molasses (EM), ethanol+Lactobacillus plantarum (EL) plus control. After 45 d of ensiling, inoculant significantly (P < 0·05) increased lactic acid (LA) concentration and decreased pH, ammonia nitrogen (AN) concentration, and aerobic bacterial and yeast counts, compared to control. After the first 3 d of aerobic exposure, LA for silages without ethanol started to decrease, while LA for E silages almost remained unchanged till the end of the aerobic exposure period. The pH in TMR silages without ethanol gradually increased, while that for E and EL remained about 4·60 and 4·00, respectively, and EL showed the lowest pH among six silages over the course of aerobic exposure. Aerobic bacterial counts in control, M and EM silages were significantly higher (P < 0·05) than those in E, L and EL, and yeast counts in E and EL silages were significantly lower (P < 0·05) than those in other silages after 9 d of aerobic exposure. The results suggest that inoculation with L. plantarum was more effective in altering fermentation characteristics than adding molasses, while ethanol showed a potential to protect TMR silages from pH increase and delayed the growth of aerobic bacteria and yeast either alone or in combination with L. plantarum.     

不同栽培模式对兰州百合生长特性产量以及品质的影响

2010-2011年,在吉林农业大学药植园内进行兰州百合的田间试验,研究了平播、垄作2种种植模式对其生长特性、产鼓以及品质的影响。结果表明,平播较垄播均能显著提高兰州百合的产量,平播比垄播在2010年和2011年分别提高30．99％和27．97％,且～级品的比例平播也较垄播高。平播模式可使茎秆健壮．但根系发达程度不及垄播。垄播提高了兰州百合的外在品质和内在品质。经过以上分析,我们提出这样的假设：在第一年进行平播,第二年做垄的栽培模式可能会使兰州百合的产量和质量达到最佳的结合。     

Effects of grazing and precipitation on herbage production,herbage nutritive value and performance of sheep in continental steppe

The present study highlights the effects of sheep grazing and precipitation on herbage and animal performance in a grazed steppe of Inner Mongolia. Experimental data were collected during grazing periods of four consecutive years (2005–2008), and effects were analysed across a gradient of seven grazing intensities. Variation in annual precipitation, reflected by the effect of ‘year’, was the major factor affecting herbage; i.e., the production and nutritive value of herbage increased with increasing precipitation. Herbage parameters were also affected by grazing intensity, as herbage production (HP) and herbage nutritive yields decreased, while herbage nutritive values increased with increasing grazing intensity. The grazing‐induced decrease in herbage nutritive yields suggests that decreases in HP offset the positive effect of grazing on the nutritive value. Liveweight gain (LWG) was predominantly affected by grazing intensity, as LWG per sheep and per ha decreased and increased, respectively, with increasing grazing intensity. However, responses varied among years: LWG per sheep was maximized by light grazing in the drought year and by moderate grazing the wet year. Our results showed that herbage shortage at high grazing intensities reduces LWG per sheep and thus diminishes responses in LWG per ha. Nevertheless, the highest grazing intensity provides highest animal production per ha in the short term; however, this is not sustainable in the mid‐ and long term because decreasing HP induces degradation processes. Based on our results, a reduction in grazing intensity that still provides 78% of the maximum LWG per ha meets the requirements of a sustainable grazing management.     

Effects of the replacement of Glu-A1 by Glu-D1 locus on agronomic performance and bread-making quality of the hexaploid wheat cv. Courtot

The aim of this study was to evaluate the cumulative and interactive effects on wheat (Triticum aestivum L.) gluten strength and mixing properties of dough associated with the duplication of the Glu-D1 locus. A partially isohomoeoallelic line RR240, in which a segment of the wheat chromosome 1D containing the Glu-D1 locus encoding the Dx2 + Dy12 subunits and translocated to the long arm of the chromosome 1A through homoeologous recombination, was assessed. Agronomic traits and yield components were studied in the translocated line RR240 and compared with the control line cv. Courtot. Both lines were evaluated under field conditions in two experimental years. Technological effects resulting from the duplication of HMW glutenin subunits Dx2 and Dy12 were evaluated using the Alveograph test, the Mixograph test and the baking test. The RR240 line was shown to have a lower agronomic performance for 1000-kernel weight and grain yield. However the duplication of the Glu-D1 allele was associated with a significant effect on dough strength and mixing resistance, and on the Zeleny sedimentation volume. Baking parameters were not significantly modified between both lines although the score values of the CNERNA test were observed to be slightly higher in RR240 than in Courtot.