Hedysarum Coronarium Research Articles

Carcass and meat quality of lambs fed fresh sulla ( Hedysarum coronarium L.) with or without polyethylene glycol or concentrate

Twenty-four male Comisana lambs aged 85 d were assigned to one of three treatments (control, sulla and PEG). The sulla group was offered fresh sulla as sole diet. The PEG lambs received fresh sulla but were also orally drenched once daily with 80 g of polyethylene glycol (PEG) with the aim to eliminate the effects of condensed tannins from sulla. The control group was fed commercial concentrate and oats hay. The animals were slaughtered at 148 d of age. Carcass and meat quality were studied. The carcass yield was lower ( P < 0.01) in the animals given sulla without PEG, compared to those given concentrates and to those given sulla plus PEG. Carcass weight was however unaffected by diet treatment. Meat from sulla lambs was lighter in colour (higher L *-value) compared to the other two groups ( P < 0.05). This effect seems to be due to the presence of condensed tannins in sulla. Saturated fatty acids 10:0, 12:0, 14:0 and 16:0 were higher ( P < 0.05) in the fat from animals of the control group compared to the other two groups. Linoleic acid (18:2 n-6) was at higher concentrations ( P < 0.0005) in the fat from control animals compared to the other two groups. Linolenic acid (18:3 n-3) was increased by four-fold by grass diets as compared to concentrate diet ( P < 0.0005). Addition of PEG to the sulla diet reduced ( P < 0.05) this fatty acid concentration. Conjugated linoleic acid was present at double concentration ( P < 0.0005) in the fat from animals fed fresh sulla (with or without PEG) compared to those given concentrates. Among the long chain n-3 fatty acids, eicosapentaenoic acid (22:5; EPA) was higher ( P = 0.001) in the fat from sulla and PEG groups compared to the control group. The n-6: n-3 ratio was increased by three-fold ( P < 0.0005) in animals given concentrate as compared to those receiving sulla.

Exploration of intra- and inter-population genetic diversity in Hedysarum coronarium L. by AFLP markers

Amplified fragment length polymorphism (AFLP) markers were used to characterize the genetic diversity within and among natural populations and cultivars of Hedysarum coronarium. Twelve populations within Tunisia were evaluated with three AFLP primer combinations. A total of 207 reproducible bands was detected of which 178 (86%) were polymorphic. The great discriminative power of AFLP markers and their ability to represent genetic relationships among Hedysarum plants was demonstrated. Genetic diversity within and among populations was assessed through Principal Component Analysis (PCA) and cluster analysis by using the Neighbor-joining clustering algorithm. AFLP technology has provided evidence of a high degree of intra- and inter-population genetic diversity in H. coronarium. AFLP banding patterns provided molecular markers correlated with the plants’ geotropism. In addition, AFLP markers can differentiate wild accessions from cultivars. Moreover, geographical origins did not correspond to population clustering.

Effects of sequential short-term grazing on different bioactive forages on viability and fecundity of established adult population of Teladorsagia circumcincta in sheep

Bioactive forages such as chicory (Cichorium intybus) or tanniferous legume sulla (Hedysarum coronarium), have been reported to lower the parasite intensities or faecal egg counts (FEC) of parasitised ruminants (Waller and Thamsborg, 2004). To our knowledge, there is no report studying the effects of these forages on established worm populations when grazed in combination. This knowledge could guide us towards optimum grazing management using special forage species as de-worming paddocks. The aim of the present study was to use the bioactive forages alone or in combination for a short period to test their effects on established T. circumcincta adult population in sheep. The tested bioactive forages were chicory and sulla, with grass/clover (Lolium perenne/Trifolium repens) providing the control forage.

The consequences of short-term grazing of bioactive forages on established adult and incoming larvae populations of Teladorsagia circumcincta in lambs

The objective of this study was to investigate the consequences of short-term grazing on bioactive forages on (i) the viability and fecundity of established adult Teladorsagia circumcincta population and (ii) the establishment and development of incoming T. circumcincta infective larvae. Forty-eight, parasite naive, 3-month old, grazing lambs were artificially infected with 8000 infective larvae of T. circumcincta on day 1 of the experiment. On day 21 p.i., lambs were allocated to one of three bioactive forage grazing treatments; chicory ( Cichorium intybus), sulla ( Hedysarum coronarium), lotus ( Lotus pedunculatus), and the control grass/clover ( Lolium perenne/Trifolium repens) forage. On day 28 of the experiment a second dose of 8000 T. circumcincta infective larvae was administered to the lambs to investigate the effects of forages on the ability of infective larvae to establish within the host. All animals were slaughtered for worm recovery on day 35, while liveweight gain, feacal egg counts (FEC) and total worm egg output were monitored regularly throughout the experiment. Although FEC or total egg output were similar among the groups, adult worm burdens at slaughter were significantly affected ( P<0.05) by forage treatment during the 2 week grazing period. Lambs grazing chicory had the lowest adult worm burdens and significantly lower numbers of male worms compared to those grazing on grass/clover ( P<0.01), while the lambs grazing on sulla or lotus had similar adult populations to grass/clover fed animals. The results from the worm recoveries of the second dose (immature worm burdens) were affected by physiologically and/or immunologically mediated mechanisms, which reduced larval establishment in all treatments. Nevertheless, immature worm burdens at slaughter were similar between chicory, sulla and grass/clover group, while the immature worm recoveries from the lotus group were significantly higher ( P<0.05) compared to those from lambs grazing grass/clover. Overall, the results of the present study support the view that chicory can be a promising candidate species in pasture management practices to control T. circumcincta burdens.

Tissue protein synthesis in lambs infected with &lt;i&gt;Trichostrongylus colubriformis&lt;/i&gt;

Fractional protein synthesis rates (FSR) were determined in lambs fed fresh sulla (Hedysarum coronarium) during an established Trichostrongylus colubriformis infection. Forty-eight days after infection, the FSR in the duodenum, ileum, mesenteric lymph nodes, spleen, liver, thymus, muscle and skin was determined. Parasite infection increased the FSR in the smooth muscle of the duodenum and ileum and in the mesenteric lymph nodes. This suggests an increase in amino acid requirement for the synthesis of constitutive proteins in these tissues. However, an established parasite infection did not result in the diversion of amino acids from muscle to the small intestine nor the liver.

Root-nodule bacteria from indigenous legumes in the north-west of Western Australia and their interaction with exotic legumes

Bacteria were isolated from root-nodules collected from indigenous legumes at 38 separate locations in the Gascoyne and Pilbara regions of Western Australia. Authentication of cultures resulted in 31 being ascribed status as root-nodule bacteria based upon their nodulation of at least one of eight indigenous legume species. The authenticated isolates originated from eight legume genera from 19 sites. Isolates were characterised on the basis of their growth and physiology; 20 isolates were fast-growing and 11 were slow-growing (visible growth within 3 and 7 d, respectively). Fast-growers were isolated from Acacia, Isotropis, Lotus and Swainsona, whilst slow-growers were from Muelleranthus, Rhynchosia and Tephrosia. Indigofera produced one fast-growing isolate and seven slow-growing isolates. Three indigenous legumes ( Swainsona formosa, Swainsona maccullochiana and Swainsona pterostylis) nodulated with fast-growing isolates and four species ( Acacia saligna, Indigofera brevidens, Kennedia coccinea and Kennedia prorepens) nodulated with both fast- and slow-growing isolates. Swainsona kingii did not form nodules with any isolates. Fast-growing isolates were predominantly acid-sensitive, alkaline- and salt-tolerant. All slow-growing isolates grew well at pH 9.0 whilst more than half grew at pH 5.0, but all were salt-sensitive. All isolates were able to grow at 37 °C. The fast-growing isolates utilised disaccharides, whereas the slow-growing isolates did not. Symbiotic interactions of the isolates were assessed on three annual, one biennial and nine perennial exotic legume species that have agricultural use, or potential use, in southern Australia. Argyrolobium uniflorum, Chamaecytisus proliferus, Macroptilium atropurpureum, Ononis natrix, Phaseolus vulgaris and Sutherlandia microphylla nodulated with one or more of the authenticated isolates. Hedysarum coronarium, Medicago sativa, Ornithopus sativus, Ornithopus compressus, Trifolium burchellianum, Trifolium polymorphum and Trifolium uniflorum did not form nodules. Investigation of the 31 authenticated isolates by polymerase chain reaction with three primers resulted in the RPO1 primer distinguishing 20 separate banding patterns, while ERIC and PucFor primers distinguished 26 separate banding patterns. Sequencing the 16S rRNA gene for four fast- and two slow-growing isolates produced the following phylogenetic associations; WSM1701 and WSM1715 (isolated from Lotus cruentus and S. pterostylis, respectively) displayed 99% homology with Sinorhizobium meliloti, WSM1707 and WSM1721 (isolated from Sinorhizobium leeana and Indigofera sp., respectively) displayed 99% homology with Sinorhizobium terangae, WSM1704 (isolated from Tephrosia gardneri) shared 99% sequence homology with Bradyrhizobium elkanii, and WSM1743 (isolated from Indigofera sp.) displayed 99% homology with Bradyrhizobium japonicum.

Root-nodule bacteria from indigenous legumes in the north-west of Western Australia and their interaction with exotic legumes

Bacteria were isolated from root-nodules collected from indigenous legumes at 38 separate locations in the Gascoyne and Pilbara regions of Western Australia. Authentication of cultures resulted in 31 being ascribed status as root-nodule bacteria based upon their nodulation of at least one of eight indigenous legume species. The authenticated isolates originated from eight legume genera from 19 sites. Isolates were characterised on the basis of their growth and physiology; 20 isolates were fast-growing and 11 were slow-growing (visible growth within 3 and 7 d, respectively). Fast-growers were isolated from Acacia, Isotropis, Lotus and Swainsona, whilst slow-growers were from Muelleranthus, Rhynchosia and Tephrosia. Indigofera produced one fast-growing isolate and seven slow-growing isolates. Three indigenous legumes (Swainsona formosa, Swainsona maccullochiana and Swainsona pterostylis) nodulated with fast-growing isolates and four species (Acacia saligna, Indigofera brevidens, Kennedia coccinea and Kennedia prorepens) nodulated with both fast- and slow-growing isolates. Swainsona kingii did not form nodules with any isolates. Fast-growing isolates were predominantly acid-sensitive, alkaline- and salt-tolerant. All slow-growing isolates grew well at pH 9.0 whilst more than half grew at pH 5.0, but all were salt-sensitive. All isolates were able to grow at 37 °C. The fast-growing isolates utilised disaccharides, whereas the slow-growing isolates did not. Symbiotic interactions of the isolates were assessed on three annual, one biennial and nine perennial exotic legume species that have agricultural use, or potential use, in southern Australia. Argyrolobium uniflorum, Chamaecytisus proliferus, Macroptilium atropurpureum, Ononis natrix, Phaseolus vulgaris and Sutherlandia microphylla nodulated with one or more of the authenticated isolates. Hedysarum coronarium, Medicago sativa, Ornithopus sativus, Ornithopus compressus, Trifolium burchellianum, Trifolium polymorphum and Trifolium uniflorum did not form nodules. Investigation of the 31 authenticated isolates by polymerase chain reaction with three primers resulted in the RPO1 primer distinguishing 20 separate banding patterns, while ERIC and PucFor primers distinguished 26 separate banding patterns. Sequencing the 16S rRNA gene for four fast- and two slow-growing isolates produced the following phylogenetic associations; WSM1701 and WSM1715 (isolated from Lotus cruentus and S. pterostylis, respectively) displayed 99% homology with Sinorhizobium meliloti, WSM1707 and WSM1721 (isolated from Sinorhizobium leeana and Indigofera sp., respectively) displayed 99% homology with Sinorhizobium terangae, WSM1704 (isolated from Tephrosia gardneri) shared 99% sequence homology with Bradyrhizobium elkanii, and WSM1743 (isolated from Indigofera sp.) displayed 99% homology with Bradyrhizobium japonicum.

Phenotypic and genotypic analysis of rhizobia isolated from pasture legumes native of Sardinia and Asinara Island.

Thirty-five rhizobial strains were isolated from nodules of Lotus edulis, L. ornithopodioides, L. cytisoides, Hedysarum coronarium, Ornithopus compressus and Scorpiurus muricatus growing in Sardinia and Asinara Island. Basic characteristics applied to identification of rhizobia such as symbiotic properties, antibiotic- and salt-resistance, temperate-sensitivities, utilization of different sources of carbon and nitrogen were studied. The results from the 74 metabolic tests were used for cluster analysis of the new rhizobial isolates and 28 reference strains, belonging to previously classified and unclassified fast-, intermediate- and slow-growing rhizobia. All strains examined were divided into two large groups at a linkage distance of 0.58. None of the reference strains clustered with the new rhizobial isolates, which formed five subgroups almost respective of their plant origin. RFLP analysis of PCR-amplified 16S-23S rDNA IGS showed that the levels of similarity between rhizobial isolates from Ornithopus, Hedysarum and Scorpiurus, and the type strains of Rhizobium leguminosarum, Mesorhizobium loti, M. ciceri, M. mediterraneum, Sinorhizobium meliloti and Bradyrhizobium japonicum were not more than 30%. Thus, it can be assumed that these groups of new rhizobial isolates are not closely related to the validly described rhizobial species.

The potential of sulla in pasture-based systems

A feed evaluation trial compared lamb growth, rumen function and protein synthesis from either pasture (perennial ryegrass (Lolium perenne)/white clover (Trifolium repens)-dominant), lucerne (Medicago sativa), sulla (Hedysarum coronarium, which contains condensed tannins (CT)) or a lucerne:sulla mixture. The 8 week trial involved 32 weaned ram lambs allocated to either pasture (80% ryegrass and 20% white clover), lucerne, sulla, or a 50:50 lucerne:sulla mixture (DM basis; 8 per diet). Measurements included feed intake, liveweight (LW) gain, rumen ammonia (NH3) and volatile fatty acid (VFA) concentrations. A sub-group of 16 lambs (4 from each treatment) were given a continuous infusion of 35S-cysteine and 35S-sulphate to measure the effect of diet on cysteine irreversible loss and absolute whole body protein synthesis (WBPS). Lambs fed pasture had the slowest (P<0.05) daily gains (116 g/day) and absolute WBPS (93 g/day) compared with lambs fed sulla (308 g LW and 152 g WBPS/day) or lucerne:sulla (281 g LW and 180 g WBPS/day). Lambs fed sulla had lower rumen NH3 concentrations (13.6 mmol/L), acetate:propionate ratios (2.6) and minor VFA concentrations (2.1%) suggesting less rumen proteolysis than lambs fed the other diets. Lamb performance was improved by feeding sulla or lucerne compared to pasture, and the lucerne:sulla mixture resulted in better performance than the average of the 2 species fed alone.

Harvesting sulla for yield and quality

Deciding when to harvest sulla (Hedysarum coronarium) can be a compromise between herbage yield and forage nutritive quality. Sulla, which grows up to 1.5 m tall, is tolerant of dry conditions and has been shown to have beneficial effects on ruminant production and health. A trial was conducted at Hamilton, New Zealand, to compare crop yield and nutritive quality of sulla harvested when it reached 30, 45, 60 and 75 cm high (retaining a stubble of 15 cm) over one growing season. Results show harvesting at 75 cm versus 30 cm increased total dry matter (DM) yield by 30%. Increasing harvest height increased total fibre content from 13.1 to 20.1 g/100g DM, (P

Rhizoctonia crown and root rot of the pasture legume, sulla (Hedysarum coronarium)

Rhizoctonia solani AG-2-2 was isolated from wilting and dying plants of sulla (Hedysarum coronarium), which is currently being assessed in eastern and southern Australia for its potential as a pasture and forage legume. Infected plants in the field had extensive rotting of the taproot, lateral roots and crown. Koch’s postulates were fulfilled using three inoculation methods. The disease may pose a considerable threat to the potential use of H. coronarium in the dryland, grazing farming systems of Australia, with resistance offering the most viable option for minimising its impact.

Gamma Proteobacteria Can Nodulate Legumes of the Genus Hedysarum

The bacteria hosted in the root nodules of the three Mediterranean wild legume species Hedysarum carnosum, Hedysarum spinosissimum subsp. capitatum, and Hedysarum pallidum, growing in native stands in different habitats in Algeria were isolated. Bacteria were recovered on yeast-mannitol-agar or on minimal media from a total of 52 nodules. Isolates were analyzed by Amplified Ribosomal DNA Restriction Analysis (ARDRA) using the enzyme CfoI, and further sorted by RAPD fingerprinting. A total of ten different types were found and their amplified 16S rDNA was sequenced and compared to databases. The BLAST alignment indicates that all the species whose sequences share 98 to 100% identity to the bacteria found in these nodules belong to the class Gammaproteobacteria and include Pantoea agglomerans, Enterobacter kobei, Enterobacter cloacae, Leclercia adecarboxylata, Escherichia vulneris, and Pseudomonas sp. No evidence of any rhizobial-like sequence was found even upon amplifying from the bulk of microbial cells obtained from the squashed nodules, suggesting that the exclusive occupants of the nodules formed by the three plants tested are members of the orders Enterobacteriales or Pseudomonadales. This is the first report of Gammaproteobacteria associated with legume nodules. Despite the presence of the related crop plant Hedysarum coronarium, specifically nodulated by Rhizobium sullae, these three Hedysarum species demonstrate to have undergone a separate path in terms of endophytic interactions with bacteria. An hypothesis to account for differences between the symbiotic relationships engaged by man-managed legumes, and those found in plants whose ecology is independent from human action, is discussed.

Quantifying Morphological Stage to Predict the Nutritive Value in Sulla (Hedysarum coronarium L.)

A precise prediction of quality of legumes in the field would enable harvests to be conducted at appropriate nutritive composition levels. Our objective was to predict the nutritive value of sulla (Hedysarum coronarium L.) with the codified morphological stage and weather parameters at two Mediterranean sites (Ancona and Sassari, Italy) in 1996, 1997, and 1998. Herbage samples were collected at progressive morphological stages, from vegetative stage to seed setting. Mean stage by weight (MSW), dry matter yield (DMY), leaf/stem ratio (L/S), crude protein concentration (CP), neutral detergent fiber (NDF), gross energy (GE), and organic matter digestibility (OMD) were determined. Forage characteristics were regressed on growing degree days (GDD) and MSW. The DMY ranged from 2 to more than 10 Mg ha−1 from vegetative to seed set while L/S decreased from almost 5.6 to 0.2 and the CP from a maximum of 295 to a minimum of 107 g kg−1 dry matter (DM). The NDF ranged from 200 to 616 g kg−1 DM and was best predicted by L/S and MSW. The GE was relatively constant across growth stages with a mean value of 18.0 MJ kg−1 DM. The OMD ranged from 398 to 846 g kg−1 organic matter (OM) and declined linearly with increasing MSW. The OMD decreased 32.6 g kg−1 OM per stage unit and followed similar trends for the two sites, with a lower level at the warmer site (Sassari). The MSW was a better predictor of sulla OMD than GDD, with a higher R2 (0.70 vs. 0.54) and a lower root mean square error.

The performance of Mediterranean dairy sheep given access to sulla ( Hedysarum coronarium L.) and annual ryegrass ( Lolium rigidum Gaudin) pastures in different time proportions

Three experiments were carried out to assess the feeding value of sulla ( Hedysarum coronarium L.) as complementary grazing source for Sarda dairy sheep basically fed on annual ryegrass ( Lolium rigidum Gaudin) pasture. In experiment 1 (E1), non-pregnant (D) and pregnant (P) ewes were allotted into three groups allocated for 9 h daily, respectively, on plots of sulla (S9), annual ryegrass (R9) or sulla for 3 h in the morning and annual ryegrass for the remaining time (S3R6). In experiment 2 (E2), the treatments were sulla (S22), ryegrass (R22) and two “time mixtures” consisting, respectively, of 3 (S3R19) or 6 h allocation on sulla (S6R16). In experiment 3 (E3) only R22 and S6R16 were compared. In both E2 and E3, milked ewes were used and the total time on the plots was 22 h daily. In E1, the total digestible herbage intake (DDMI), measured by the n-alkane method, was affected by the interaction between sheep physiological state and grazing system ( P<0.01). No effect of the above factors on sheep body weight and body condition changes was evident. In E2, DDMI did not differ between groups up to May when S22 and S3R19 outperformed R22, S6R16 behaving as intermediate ( P<0.05). Milk yield paralleled DDMI results. Milk composition was unaffected, except for milk urea ( P<0.001), lower in R22 (34.0 mg/dl) than the other groups (39.6 mg/dl, S3R19; 44.4 mg/dl, S6R16; 44.3 mg/dl, S22). In E3, S6R16 ewes grazed for less than 50% of the allocation time on sulla. To conclude, S3R19 can partially offset the decay of grass nutritive value in spring but results are intermediate between those of the mono-specific pastures. S6R16 is less beneficial than S3R19 possibly due to the detrimental effect of condensed tannins on grazing behaviour.

The role of plants containing secondary compounds in sustainable deer farming - a review

The productivity and health of farmed deer is improved by substituting perennial ryegrass-based pasture with forages containing condensed tannins (CT) and/or sesquiterpene lactones. Benefits have included improved lactation, growth, trace element status, resilience to internal parasites and reductions in parasite larval development. Forages evaluated for deer include the forage legumes sulla and birdsfoot tref oil, which contain CT, and the herb chicory, which contains both CT and sesquiterpene lactones. Autumn grazing of weaner deer on chicory has shown growth can be increased whilst anthelmintic requirement reduced compared to grazing of perennial ryegrass/ white clover pasture. The importance of secondary compounds relative to other nutritive characteristics of alternative forage species, such as low fibre and highly digestible carbohydrate concentrations, have not been fully characterised, but they are likely to contribute to improved deer health. Unlike sheep and cattle, deer pr oduce salivary proteins that bind CT, allowing them to consume plants containing higher CT concentrations than sheep and cattle. The effect of CT upon the digestion and absorption of protein, which has been determined for other domestic ruminants, needs to be measured in deer fed forage diets, to establish if beneficial effects exist. In vitro work has shown direct inhibitory effects of CT and sesquiterpene lactones extracted from forages on deer internal parasite larvae. The faeces, rumen and abomasal fluid of deer grazing chicory also contained substances reducing the viability of parasite larvae. Alternative plant species such as chicory, birdsfoot trefoil and forage willows containing secondary compounds will play an important role in low chemical sustainable deer farming. Keywords: anthelmintic, Cichorium intybus,condensed tannins, forage, Hedysarum coronarium, internal parasites, protein, red deer

Adaptation and potential contribution of temperate perennial legumes to the southern Australian wheatbelt: a review

Deep-rooted perennial pasture plants can play an important role in solving the environmental problems of rising watertables, dryland salinity and soil acidification in the wheatbelt of southern Australia. These problems are attributed to the extensive clearing of perennial native vegetation and its replacement with shallow-rooted winter-growing annual crops and pastures. Deep-rooted, herbaceous perennial legumes, particularly lucerne (Medicago sativa L.), are seen as making an increasing contribution in the cropping zones where high rates of symbiotic nitrogen fixation and increased water use are high priorities. This paper reviews the current use and the potential of a range of temperate perennial legumes for the wheatbelt of southern Australia. The genera examined include Medicago, Hedysarum, Trifolium, Onobrychis, Lotus, Galega, Astragalus, Lathyrus, Anthyllis, Psoralea, Dorycnium, Lespedeza and Securigera. There is considerable scope to expand the use of lucerne; however, there is also a need for alternative perennial species to increase biodiversity and to fill niches where lucerne is less suited. Based on current knowledge, the species with the most promise to complement lucerne include sainfoin (Onobrychis viciifolia Scop.) and sulla (Hedysarum coronarium L.) on alkaline soils, strawberry clover (Trifolium fragiferum L.) in wet or mildly saline niches and Lotus and Dorycnium spp. on waterlogged and/or acid soils.

Diet selection by deer: principles, practice and consequences

The role of diet selection by farmed deer in their nutrient intake and species selection, and the consequences for the management of forages, is considered. In common with sheep and cattle, sward surface height (SSH) is the most influential sward physical factor on the ability of deer to meet their daily nutrient demand from grazed pasture, and a SSH of 10cm is required for maximum intake and performance. Deer discriminate among pasture species, generally preferring legumes and herbs to grasses. The grass dominance and low proportion of clover in typical permanent pasture grazed by deer reflects their selection for clover and avoidance of grass. This dominance of grass and the difficulty deer face in selecting for alternative species that are present only in a low proportion may constrain intake even when sward height is not limiting. Summer-growing forage species such as red clover (Trif olium pratense), white clover (Tri folium repens), birdsfoot trefoil (Lotus corniculatus), sulla (Hedysarum coronarium) and chicory (Cichorium intybus) have high nutritive value, and result in high liveweight gains by deer when provided as specialist swards at critical feeding times. Recent studies indicate that ruminants prefer to eat mixed diets, and management systems that enable mixed grass-clover pastures with a high proportion of legume to be sustained under selective grazing by deer would provide high nutritive value and maintain a balance between winter and summer in the seasonal distribution of pasture dry matter production. Keywords: Cervidae, deer, diet selection, forage, grazing behaviour, nutrient intake, preference

First year seed softening in three Hedysarum spp. in southern Queensland

Seed softening was investigated in 41 lines of Hedysarum coronarium, 5 lines of H. carnosum and 8�lines of H. flexuosum grown at Oakey, Queensland in 2000. After testing for initial hard seed content in each line, the remaining hard seeds were placed on the soil surface at Kingsthorpe on 15 January 2001. Changes in hard seed levels over the ensuing summer-autumn seed softening period were measured. The initial hard seed content in each species ranged from 20 to 79% in H. coronarium; 31 to 79% in H. carnosum; and 54 to 83% in H. flexuosum. No significant difference in the time of seed softening between accessions or species was identified. Despite the similar timing, the extent of softening varied greatly between accessions and species. The proportion of initially hard seed that softened ranged from 54 to 95% in H. coronarium; 27 to 45% in H. carnosum; and 50 to 74% in H. flexuosum. Accessions of H. coronarium and H. flexuosum softened the greatest proportion of seed between 15 January and 22�February with reducing amounts thereafter. Accessions of H. carnosum softened less seed over this period, appearing to display a slower, more constant rate of softening. Although total hard seed levels were relatively low, there was sufficient variability in hard seed levels to provide some scope for selection of desired hard seed characteristics.

Comparison of Sulla-hay and Sulla-silage in the lactating ewes and their effects on milk and cheese characteristics

Two methods of storage of Sulla- and oat-grass (silage or hay) were compared. Forty-six homogeneous lactating ewes, housed indoors, were divided into two groups and after 35 days of diet adjustment, were fed ad libitum twice a day, either Sulla- ( Hedysarum coronarium L.) and oat-hay (control group) or Sulla- and oat-silage in partial substitution of hay (silage group). Both groups were fed with 0.5 kg of commercial concentrate. The dietary treatment started 60 days post-lambing and lasted for 58 days. Every day, the feeding intake for each group was recorded. Individual milk yield was measured weekly and at the same time, milk samples were collected and analysed by Milko-Scan 605. Every week, the milk yield of each group, collected for 48 h before and frozen at 5 °C, for a total of eight replications, was analysed for fat, protein, casein, whey-protein, non-protein nitrogen, urea, lactose percentages, pH, and microbiological contamination. The cheese were made according to the traditional cheese making process of Sicilian Pecorino cheese. On the basis of Flieg (82) and Vanbelle (60) points, the silage turned out to be very good, with a good nutrient value (0.60 milk FU/kg). The dry matter (DM) intake did not differ between feeding groups (1585 versus 1639 g per day of DM, respectively). The silage level of substitution with regard to hay was equal to 27%. The silage group ewes did not show significant differences as regards daily milk yield (0.59 kg per day versus 0.60 kg per day), fat percentage (8.12% versus 8.03%), and protein percentage (5.53% versus 5.40%), but increased their body weight (+3.82 kg versus +2.08 kg, P≤0.05). Cheese yield and microbiological analysis did not show significant differences among the mature cheese of both groups.

Rhizobium sullae sp. nov. (formerly 'Rhizobium hedysari'), the root-nodule microsymbiont of Hedysarum coronarium L.

This work is the completion of a series of reports describing the nitrogen-fixing bacterial symbionts of sulla (Hedysarum coronarium L., Leguminosae) and providing the grounds for their proposal as a new taxon. The introduction summarizes a large amount of previous evidence gathered on the physiology, genetics and ecology of such organisms, which have in the past been referred to provisionally as 'Rhizobium hedysari'. Upon adding 16S RNA sequencing, amplified rDNA restriction analysis of the rrn operon, DNA-DNA hybridization homology and analysis of low-molecular-mass RNA species, it is concluded that the group of strains that specifically nodulate sulla consists of a coherent set of isolates that differ from previously described rhizobia to an extent that warrants the constitution of the species boundary. The name Rhizobium sullae sp. nov. is proposed, with isolate 1S123T (=USDA 4950T = DSM 14623T) as the type strain.