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International audience; This work was performed to investigate on the yeast ecology of durum wheat to evaluate the interaction between kernel yeasts and the commercial baker's yeast Saccharomyces cerevisiae during dough leavening. Yeast populations were studied in 39 genotypes of durum wheat cultivated in Sicily. The highest level of kernel yeasts was 2.9 Log CFU/g. A total of 413 isolates was collected and subjected to phenotypic and genotypic characterization. Twenty-three yeast species belonging to 11 genera have been identified. Filobasidium oeirense, Sporobolomyces roseus and Aureobasidium pullulans were the species most commonly found in durum wheat kernels. Doughs were co-inoculated with yeasts isolated from wheat kernels and commercial Saccharomyces cerevisiae, in order to evaluate the interactions between yeasts and the leavening performance. Yeast populations of all doughs have been monitored as well as dough volume increase and weight loss (as CO2) measured after 2 h of fermentation. The doughs whose final volume was higher than control dough (inoculated exclusively with S. cerevisiae) were those inoculated with Naganishia albida, Vishniacozyma dimennae (118 mL each), and Candida parapsilosis (102 mL). The weight losses were variable, depending on the co-culture used with S. cerevisiae and the values were in the range of 0.08-1.00 g CO2/100 g. The kernel yeasts species C. parapsilosis, N. albida, P. terrestris, R. mucilaginosa and V. dimennae deserves future attention to be co-inoculated with the commercial starter S. cerevisiae in order to improve the sensory characteristics of bread.

In the present work the microbial dynamics in wheat kernels were evaluated over time. The main aim of this research was to study the resistance of lactic acid bacteria (LAB) and yeasts associated to unprocessed cereals used for bread making during long term conservation. To this purpose four Triticum durum Desf. genotypes including two modern varieties (Claudio and Simeto) and two Sicilian wheat landraces (Russello and Timilia) were analysed by a combined culture-independent and -dependent microbiological approach after one, two or three years from cultivation and threshing. DNA based MiSeq Illumina technology was applied to reveal the entire bacterial composition of all semolina samples. The samples showed a different distribution of bacterial taxa per variety and time of storage. The groups mostly represented were Stenotrophomonas, Pseudomonas, Erwinia, Delftia and Sphingomonas genera, Enterobacteriaceae and Oxalobacteriaceae families, and Actinobacteria phylum. Among LAB, only Enterococcus genus was detected barely in a single sample (Simeto stored for one year) by the next generation sequencing, indicating that LAB remained unassigned or their abundances were below 0.1% or their DNAs were rendered inaccessible. Plate counts showed consistent differences in relation to genotypes and duration of storage, with the highest levels found for total mesophilic microorganisms detected up 6.8 Log CFU/g. Colonies of presumptive sourdough LAB were detected only in a few samples. Cocci constituted the major group of LAB in almost all samples. Following the enrichment procedure, almost all samples were characterised by the presence of acidifying microorganisms. All isolates collected before and after enrichment represented 28 different strains belonging to 10 species of Enterococcus, Lactobacillus and Pediococcus genera. The most resistant species during aging were Enterococcus faecium, Enterococcus durans, Lactobacillus brevis, Lactobacillus pentosus and Lactobacillus paracasei demonstrating that lactobacilli and enterococci are able to overcome the stressing conditions represented by cereal storage better than other LAB genera commonly found associated to cereals after harvest. Yeast community included mostly species with no interest in bread making.

Durum wheat bran (DWB) is a by-product mostly used in feeding ruminants, contributing to decrease in the utilization of feeds suitable as foods for human consumption, thus improving the sustainability of livestock production. However, the potential benefits of DWB, due to its content in phenolic acids, mainly consisting of ferulic acid with antioxidant properties, have not been well clarified yet. Accordingly, in this experiment, 36 lactating cows divided into three groups received, over a period of 100 days, one of three concentrates including DWB at 0% (DWB0), 10% (DWB10), or 20% (DWB20). The concentrates were formulated to be isoproteic and isoenergetic and, to balance the higher fiber content of the concentrates with DWB, the hay in the diets was slightly reduced. During the trial, the group feed intake and the individual milk production were monitored, and cheese was made with bulk milk from each group. Milk yield and microbiological characteristics of milk and cheese were similar among groups, indicating no DWB effect on cows performance and fermentation process. Milk from DWB20 group resulted slightly higher in casein and curd firmness (a2r). In cows fed DWB, the higher polyphenol intake was responsible for higher blood contents of these bioactive compounds, that seemed to have contributed in reducing the level of reactive oxygen metabolites (ROMs), which were higher in DWB0 cows. DWB20 cheeses showed a higher polyphenol content, lower number of peroxides, and higher antioxidant capacity than DWB0 cheeses. DWB20 and DWB10 diets resulted less expensive. In addition, the DWB20 group showed the best indexes heFCE (human edible feed conversion efficiency = milk/human edible feed) and NFP (net food production = milk &minus, human edible food), expressed as crude protein or gross energy. In conclusion, the DWB fed to dairy cows at 12% of diet dry matter (DM) can lead to benefits, such as the improvement of oxidative status of cows, milk quality, shelf-life, and functional properties of cheese, and might contribute to reduce the feeding cost and limit the human-animal competition for feeding sources.

Three obligately heterofermentative lactic acid bacteria (LAB) strains (Lactobacillus sanfranciscensis PON100336, Leuconostoc citreum PON10079 and Weissella cibaria PON10030) were used in this study as a multi-species starter culture for sourdough production. The starter inoculum was prepared and propagated in sterile semolina extract (SSE) broth. Acidification kinetics, microbiological counts detected on specific media for sourdough LAB, polymorphic profile comparison and species-specific PCRs evidenced a stability of the liquid inoculum over time determining its suitability for direct addition to semolina. In order to validate this innovative method for the production of durum wheat (Triticum durum Desf) sourdoughs, 15 semolinas (from ten old and five modern genotypes cultivated in Sicily, southern Italy) were used to prepare the SSEs and to produce sourdoughs and finally breads. Chemical and microbiological analyses of the sourdoughs and the evaluation of the quality parameters (weight loss, height, crumb and crust colour, image analysis and volatile organic compound generation) of the resulting breads indicated that the direct addition of the liquid inocula propagated in SSE is a valuable method to stabilise the production of sourdoughs. The differences registered during the technological characterisation of the breads were underlined by the sensory tests and the multivariate analysis and are mainly imputable to the type of semolina.

This experiment aimed to investigate the possibility to increase the carcass weight of dairy breed lambs and produce moderate-fat meat by applying inexpensive feeding strategies based on restriction and through the use of a fibrous byproduct such as the durum wheat bran (DWB). Sixty-five 45-day-old lambs of the Valle del Belice breed, divided into 6 groups, were fed alfalfa hay supplemented with concentrate feeds including DWB at 0% or 20% (DWB0, DWB20), supplied ad libitum (L) or restricted at 75% (R), and slaughtered at 90 or 120 days of age. The groups were as follows: DWB0-90L (n = 14), DWB20-90L (n = 14), DWB0-120R (n = 10), DWB20-120R (n = 9), DWB0-120L (n = 9), DWB20-120L (n = 9). The diet did not affect feed intake, growth or carcass weight of lambs fed ad libitum, whereas 120-day-old lambs fed DWB associated to restriction showed the lowest weight gain (105 vs. 170, 185 and 190 g/day in DWD20-120R, DWB0-120R, DWB0-120L and DWB20-120L, p = 0.04). The incidence of fat tissue in the hind leg increased (p &lt, 0.0001) from 90L (5.82 and 5.45% with DWB0 and DWB20) to 120R (8.80 and 8.43% with DWB0 and DWB20) and 120L lambs (10.7 and 11.8% with DWB0 and DWB20). Older lambs&rsquo, meat, compared to that of 90L lambs, showed analogous levels of intramuscular fat, higher water retention, tenderness and lightness, and a more intense red colour. In meat from 120-day-old lambs, DWB intake tended to reduce the fat level (p = 0.009) and increased polyphenol content (1.10 vs. 1.62, and 1.02 vs. 1.65 g GAE/kg dry matter (DM) in 120R and 120L lambs, p = 0.02), antioxidant capacity (12.8 vs. 14.9, and 12.8 vs. 15.7 mmol trolox eq/kg DM in 120R and 120L lambs, p = 0.02), and the presence of n-3 polyunsaturated fatty acids (FA) (1.61 vs. 2.81, and 1.43 vs. 2.61 g/100 g FA in 120R and 120L lambs, p = 0.007), thereby improving the meat&rsquo, s health properties. The panelists perceived the effects of DWB inclusion as well as the feeding level with triangle tests.

Summary Knowledge of the effects of agricultural practices on weed seedbank dynamics is essential for predicting future problems in weed management. This article reports data relative to weed seedbank structure after 18 years of continuous application of conventional tillage (CT, based on mouldboard ploughing) or no tillage (NT) within three crop sequences (continuous wheat, WW; wheat–faba bean, WF; and wheat–berseem clover, WB). Tillage system did not affect the size of the total weed seedbank, but altered both its composition and the distribution of seeds within the soil profile. In particular, the adoption of CT favoured some species (mainly Polygonum aviculare), whereas the continuous use of NT favoured other species (Papaver rhoeas, Phalaris spp. and Lactuca serriola). The effects of tillage system on weed seedbank size and composition were less pronounced in the WB cropping system than in either the WW or WF. Compared with WF and WB, WW resulted in an increase in total weed seedbank density (about 16 000 seedlings m−2 in WW, compared with 10 000 and 6000 seedlings m−2 in WF and WB, respectively) and a reduction in weed diversity, with a strong increase in some species (e.g. Polygonum aviculare). Our results for the effect of NT application on weed seedbank size and composition suggest that farmers should only apply such a conservative technique within an appropriate crop sequence.

This paper reviews the main results from a set of experiments carried out in a semiarid Mediterranean environment during the past 25 years on faba bean (Vicia faba L.), a crop traditionally grown in southern Italy and Sicily under rainfed conditions. These experiments focused on the residual effects of faba bean on subsequent crop(s) and assessment of the nitrogen (N) balance during the crop cycle, paying attention to both the environmental release of N (losses via volatilisation and denitrification) and estimates of N2 fixation as influenced by tillage system, intercropping, and presence/absence of mycorrhizal inoculum. Faba bean relied on N2 fixation more than other grain legumes typically grown in the Mediterranean region (e.g., chickpea). Contributing reasons were the higher plant N demand of faba bean and its lower capacity to use soil mineral N. This implies higher N benefits for subsequent crop(s) as well as higher risk of N losses from the plant–soil– atmosphere system via leaching, denitrification, and volatilisation. Results from these experiments contribute to better defining the role of faba bean in Mediterranean agro-ecosystems and to identifying technical solutions that maximise the potential benefits of faba bean as a fertility-building crop.

In this paper volatile organic compounds (VOCs) from durum wheat cultivars and landraces were analyzed using PTR-TOF-MS. The aim was to characterize the VOC’s profile of the wholemeal flour and of the kernel to find out if any VOCs were specific to varieties and sample matrices. The VOC data is accompanied by SDS-PAGE analyses of the storage proteins (gliadins and glutenins). Statistical analyses was carried out both on the signals obtained by MS and on the protein profiles. The difference between the VOC profile of two cultivars or two preparations of the same sample - matrices, in this case kernel vs wholemeal flour - can be very subtle; the high resolution of PTR-TOF-MS - down to levels as low as pptv - made it possible to recognize these differences. The effects of grinding on the VOC profiles were analyzed using SIMPER and Tanglegram statistical methods. Our results show that it is possible describe samples using VOC profiles and protein data.

A better understanding of the genotype response to N fertilization under weed competition is necessary to identify varieties that exhibit high N use effi ciency even when weeds compete for available N. Such varieties may be more suitable for low input or organic systems. Th is study assessed the variations in nitrogen use effi ciency (NUE) (and its components) and the recovery of 15 N-labeled fertilizer in three durum wheat (Triticum durum Desf.) genotypes (one landrace and two varieties that diff er in terms of plant growth, grain yield potential, and adaptability to stressful environments) grown in the presence or absence of interspecifi c competition and varying soil N availability (0 or 80 kg N ha –1 fertilization). Th e results showed that wheat genotypes had diff erent grain yield potentials and the yields were similar when plants were grown in conditions of low N availability and in presence of interspecifi c competition. Diff erences among genotypes in N uptake effi ciency were very small, and the low NUE value observed for the landrace seemed to be due to its reduced ability to use absorbed N for increasing grain yield compared with the two varieties. Furthermore, the genotypes showed diff erent competitive abilities against competitor, and seemed to depend on the genotypes’ ability to reduce resource availability (N) for their competitors rather than on their ability to tolerate a reduction in contested resources due to competitors.

No tillage (NT) soil management has largely been promoted because of its potential to generate both economic and environmental benefits. However, it often leads to reductions in crop yield and quality, which in many cases have been attributed to the effects this technique has on the nitrogen (N) dynamics in the soil–plant system. This 2-year study, performed within a long-term experiment in which NT was continuously applied for over 15 years, aimed to verify whether and to what extent the use of NT affects soil N availability, recovery of 15 N-labeled fertilizer, and N use efficiency (NUE) and its components (N uptake efficiency, NUpE; N utilization efficiency, NUtE). Durum wheat was the focal crop. NT was evaluated and compared with conventional tillage (CT) within three crop sequences: continuous wheat (WW), wheat–faba bean (WF), and wheat–berseem clover (WB). At the same time, the timing of N fertilization was varied (either distributing 100 kg N ha −1 all at once at crop emergence or applying 50% at crop emergence and 50% at the end of tillering; no N-fertilizer treatment was included as a control). The data indicated that, compared to CT, NT had a detrimental effect on wheat productivity in WW but improved yields in WF and WB. NT was associated with less N uptake by wheat, mainly attributable to a decrease in soil N availability, and to a lesser extent, to a decrease in the 15 N-fertilizer recovery. This reduction in uptake was markedly more evident in WW than in WF or WB, and when all of the 15 N-fertilizer was applied at crop emergence. The effects of tillage system on NUE varied by crop sequence: NT increased NUE (+18% on average compared to CT) in WF, but had the opposite effect in WW (−17% on average). These results suggest that the adoption of the NT technique by farmers must be accompanied by a reorganization of the components of crop management, such as crop rotation and the rate and timing of N fertilization.

Aims: To evaluate the productivity and N2 fixation of a range of Mediterranean forage legume species as well as their ability to be grown in mixture with a forage grass, and to verify whether N transfer occurs from the legume to the non-legume component of the mixtures and, if so, to what extent this process is affected by legume species. Methods: Seven legume species (Hedysarum coronarium L., Medicago scutellata L., Trifolium resupinatum L., Trifolium squarrosum L., Trigonella foenum-graecum L., Vicia sativa L., Vicia villosa Roth) were grown alone or in mixture with annual ryegrass (Lolium multiflorum L.). Biomass and N yields and biological N2 fixation (15N dilution technique) were measured. N transfer from legume to the non-legume component was also assessed. The efficiency of the intercrops was evaluated using the land equivalent ratio (LER), aggressivity index, and competitive ratio. Results: Differences were observed among the monocropped legumes for biomass yield, N2 fixation, and ability to utilize inorganic soil N. Moreover, the proportion of legume species to the total biomass yield of the intercrop varied from 30 % (T. resupinatum) to 69 % (T. foenum-graecum). All intercrops showed an advantage over monocrops in terms of biomass and N yields (LER and NLER values always >1). No N transfer occurred from legume to ryegrass in any of the mixtures. Conclusions: The large differences observed among the studied legumes must be taken into account when trying to develop cropping systems with more efficient N use. Moreover, as all legume–ryegrass intercrops used natural resources more efficiently than pure crops, intercropping is a relevant cropping strategy for sustainable agricultural systems in Mediterranean environments.

Arbuscular mycorrhizal fungi (AMF) have a major impact on plant nutrition, defence against pathogens, a plant's reaction to stressful environments, soil fertility, and a plant's relationship with other microorganisms. Such effects imply a broad reprogramming of the plant's metabolic activity. However, little information is available regarding the role of AMF and their relation to other soil plant growth-promoting microorganisms in the plant metabolome, especially under realistic field conditions. In the present experiment, we evaluated the effects of inoculation with AMF, either alone or in combination with plant growth-promoting rhizobacteria (PGPR), on the metabolome and changes in metabolic pathways in the roots of durum wheat (Triticum durum Desf.) grown under N-limited agronomic conditions in a P-rich environment. These two treatments were compared to infection by the natural AMF population (NAT). Soil inoculation with AMF almost doubled wheat root colonization by AMF and decreased the root concentrations of most compounds in all metabolic pathways, especially amino acids (AA) and saturated fatty acids, whereas inoculation with AMF+PGPR increased the concentrations of such compounds compared to inoculation with AMF alone. Enrichment metabolomics analyses showed that AA metabolic pathways were mostly changed by the treatments, with reduced amination activity in roots most likely due to a shift from the biosynthesis of common AA to γ-amino butyric acid. The root metabolome differed between AMF and NAT but not AMF+PGPR and AMF or NAT. Because the PGPR used were potent mineralisers, and AMF can retain most nitrogen (N) taken as organic compounds for their own growth, it is likely that this result was due to an increased concentration of mineral N in soil inoculated with AMF+PGPR compared to AMF alone.

During a 6 week trial in summer, 3 homogeneous groups, each consisting of 5 Comisana ewes and 5 Rossa Mediterranea goats, grazed watered forage resources during day (D) or night (N), or were housed indoor and supplied with mowed herbage (H). Maximum THI peaked at 94 at the end of July, and was almost constantly higher of 80. Milk yield was higher in N than in D and H goats, whereas N ewes produced more milk than H group, but their milk yield was higher than D ewes only in the period with the highest THI values. The lower urea in N goat milk, and the higher casein in N ewe milk, seem to indicate a better efficiency in dietary nitrogen utilization of night grazing animals. N ewes showed lower SCC in milk, and higher incidence of clotting milk samples, in comparison to other ewes. N goats and ewes showed lower rectal temperature and pulse rate in the afternoon and, among metabolic parameters, higher hematic level of sodium. Night grazing was confirmed to be a management practice for increasing heat tolerance, to which goats appeared to be more sensitive in terms of milk yield.

Sulla is a biennial forage legume native to the central-western Mediterranean Basin and has increasing interest for regions with Mediterranean-climate. The Italian germplasm is a reservoir of variation for important agronomic traits. This study aimed to support breeding programs by investigating patterns of agronomic, adaptive and morpho-physiological variation among ecotypes collected from the three main Italian regions of species cultivation: central Italy, and the two islands of Sicily and Sardinia. Forage yield and morpho-physiological traits were evaluated at a site with Mediterranean climate in Sicily. Forage yield and cold tolerance in a cold-prone site of northern Italy were also assessed, to locate useful germplasm for widening crop resilience and climatic adaptability. Collection regions, and ecotypes within regions, differed for total forage yield and final plant survival, but their responses were subjected to interactions with test location. Specific adaptation dominated the adaptive responses of ecotypes and elite commercial varieties. Ecotype adaptation to cold winter was associated with latitude and, more specifically, the extent of cold stress in collecting sites. The ecotype collection region had a bearing also on morpho-physiological characteristics. A few ecotypes from central Italy performed outstandingly with respect to elite varieties, displaying wide adaptation across cold-prone and drought-prone environments.

Conservation tillage techniques are becoming increasingly popular worldwide as they have the potential to generate environmental, agronomic, and economic benefits. In Mediterranean areas, studies performed on the effects of conservation tillage [in comparison with the conventional tillage technique (CT)] on grain yield of cereal crops have reported contradictory results as well as considerable year-to-year variation, demonstrating how the impact of different soil tillage techniques on crop productivity is strongly site-specific. The present paper summarises the main results from a set of experiments carried out in Sicily during the last 20 years in which we compared no tillage (NT) to CT in terms of their respective effects on the productivity and quality of durum wheat, while at the same time varying some other crop management practices ( e.g. crop sequence, N fertilisation, wheat genotype, sowing time). On average, no differences were observed between the two tillage techniques; yields were 3.84 and 3.87 Mg ha –1 for CT and NT, respectively. However, NT guaranteed superior yield when water stress during the crop cycle was high, whereas CT led to higher yields when water availability was adequate. Moreover, the results suggest that the use of NT needs to be accompanied by a rational crop sequence. In fact, a cumulative detrimental effect of NT over time was found for continuous wheat. Finally, grain quality in terms of protein content was slightly higher for CT (15.1%) than NT (14.4%). Thus, when using NT, the rate of nitrogen fertiliser application should be increased to offset this difference.

The aim of this research was to evaluate the effects of continuous and rotational grazing of different forage species on milk production in ewes. The forage species were chicory (Cichorium intybus L.), a mixture of oat (Avena sativa L.) and berseem clover (Trifolium alexandrinum L.), and sulla (Hedysarum coronarium L.). Forty ewes were divided into 5 groups, and subjected to one of the following treatments: continuous grazing on chicory, continuous grazing on the mixture, continuous grazing on sulla, rotational grazing on the mixture, or rotational grazing on sulla. Among the species continuously grazed, chicory showed a lower biomass than the mixture, or sulla. Ewes grazing chicory produced more milk than ewes grazing the mixture (1243 vs. 1003 g/d; P ≤ 0.01), whereas ewes grazing the sulla showed an intermediate milk yield (1136 g/d). During the experiment there was a gradual decrease in milk yield which was less pronounced for chicory, than for the other species. The fat, protein, and casein contents in the milk increased as the milk yield decreased. Compared with continuous grazing, rotational grazing produced a greater forage biomass. Moreover, ewes on continuous grazing produced a higher milk yield than those under rotational conditions (1070 vs. 951 g/d; P ≤ 0.05). The grazing period also influenced milk production: in the first period (April), when more forage was available, the ewes produced more milk than during the second period (May). Furthermore, the ewes grazing sulla recorded a higher milk yield in the first period, compared to those grazing the mixture (1377 vs. 1159 g/d; P ≤ 0.05), but this difference was not evident during the second period. These results highlight the productivity of sulla, and the potential of chicory in providing a lasting good-quality herbage, and therefore the positive effect of these species on dairy performance in grazing ewes. Although rotational grazing produced more forage biomass, the results indicate that it does not always lead to increased milk production in animals, because of the lower nutritional value of forage grazed in an advanced phenological stage.

BACKGROUND: This study evaluated the effects on lamb growth, carcass traits and meat quality of replacing conventional soybean meal in the diet with alternative legume grains. RESULTS: Twenty-eight male lambs of Comisana breed weighing 16.9 ± 2.7 kg at weaning (66 ± 6 days old) were assigned to one of four diets. Until slaughter at 129 ± 6 days of age, each group received ad libitum pelleted alfalfa hay and concentrates differing in the source of protein: chickpea, faba bean, pea or soybean meal. Lambs fed chickpea showed higher dry matter and protein intakes from concentrate than those fed soybean. Lambs' growth, carcass weight and net dressing percentage did not vary by protein source, although chickpea lambs had more perirenal and pelvic fat than those in the soybean group. Diet did not affect chemical composition, colour, thawing and cooking losses, tenderness, and sensory properties of meat. Chickpea increased trans-vaccenic and linoleic acid, and chickpea and faba bean increased the isomers of conjugated linoleic acid. CONCLUSIONS: Legume grains can completely replace soybean meal in concentrate, resulting in lamb carcasses and meat of comparable quality. Chickpea leads to an increase in feed intake of lambs and in fat depots in the carcass, and a more beneficial fatty acid profile. Copyright © 2012 Society of Chemical Industry

In Mediterranean countries, forage grasses and legumes are commonly grown in mixture because of their ability to increase herbage yield and quality compared with monocrop systems. However, the benefits of intercropping over a monocrop system are not always realized because the efficiency of a grass–legume mixture is strongly affected by agronomic factors. The present study evaluated productivity, N2 fixation, N transfer, and N recovery of berseem clover (Trifolium alexandrinum) grown in pure stand and in mixture with annual ryegrass (Lolium multiflorum) under high or low defoliation frequencies and varying plant arrangements (sowing in the same row or in alternating rows). On average, the berseem–ryegrass mixtures resulted in a greater yield and N yield than the monocrops. When mixed together, ryegrass was more efficient than berseem at absorbing soil N, increasing the reliance of berseem on N2 fixation. Both defoliation management and plant arrangement affected forage yield and the quality of the mixture, modifying the proportion of the two components, the N content of the forage, and the symbiotic N2 fixation of the legume. Reducing the proximity between plants of the two species may benefit the weaker component of the mixture. No apparent transfer of fixed N from berseem to ryegrass was detected.

The nutritional effects of sulla (Hedysarum coronarium L.) forage containing condensed tannins (CT) on growth of lambs, and carcass and meat quality were investigated. Thirty-two male Comisana lambs aged 100 ± 8 days weighing 19.0 ± 2.8 kg were fed fresh forage of sulla or CT-free annual ryegrass (Lolium multiflorum Lam. subsp. Wersterwoldicum) for 49 days until slaughter; in addition, each lamb was supplied with 200 g/days of concentrate. Eight lambs per diet had been previously treated with anthelmintic drugs to remove nematode parasites. Measurements of BW and feed intake, and counts of faecal nematode eggs were made. Carcass parameters were recorded after slaughter, and tissue components of the hind leg were determined. Longissimus dorsi meat was evaluated for pH, colour, thawing and cooking losses, Warner-Bratzler shear force, chemical composition and sensory properties based on triangle tests. Relative to ryegrass-fed lambs, sulla-fed lambs had significantly greater dry matter (DM) and protein intake, a more favourable feed conversion ratio, and superior growth rate, final BW at 150 days of age, carcass weight, yield and fatness. These results were attributed to the high protein and non-structural carbohydrate content of sulla, and also to the moderate CT content of sulla (16.7 and 20.3 g/kg of DM in offered and consumed sulla forage, respectively). Anthelmintic treatment did not affect lamb growth, as the level of parasitic infection (initial and final) was low. The physical, chemical and sensory properties of the lamb meat were not influenced by diet.

The objectives of this study were to 1) evaluate the productivity and forage quality of Atriplex halimus, 2) investigate modifications to shrub structure induced by grazing, and 3) assess live weight changes in lambs grazing on A. halimus with and without a feed supplement (wheat straw ± barley grain). The results showed that A. halimus had low productivity (approximately 1000 kg DM ha–1) but high tolerance to grazing by lambs, although minor modifications in plant structure due to grazing were observed. Lambs grazing A. halimus as a sole diet lost weight (about 60 g lamb−1 d–1; P < 0.01), probably as a consequence of the high salt content of the forage reducing both intake and digestibility. No significant benefits were obtained from the provision of wheat straw as an ad libitum supplement, possibly because the lambs were able to utilize understorey plants having a chemical composition similar to straw. Lambs supplemented with both wheat straw and barley grains (200 g lamb−1 d–1) had a significantly higher live weight (P < 0.01) than those grazing on A. halimus alone. The results suggest that a diet of A. halimus is not sufficient to maintain lamb live weight, and that supplementation with an energy source is necessary for lambs to gain weight.

This investigation aimed to individuate the dietary factors affecting the milk urea nitrogen (MUN) concentration in goats grazing herbaceous pasture and, particularly, to verify the relationship linking the diet crude protein (CP) content to MUN. A total of 205 individual observations regarding dietary and milk variables of 37 Girgentana goats involved in two experiments were used. Goats, averaging 154±14 days in milk and 38.1±5.4 kg of live weight, grazed on swards and received 500 g/d of barley meal. Sward biomass, herbage selected by goats and individual milk yield were measured and sampled weekly. The herbage intake and diet digestibility were estimated by the n-alkane method. Milk urea content was determined by an enzymatic method and transformed in MUN (MUN=urea*0.4665). The MUN concentration (9.7-35.4 mg/dl) was positively correlated with diet CP content (13.7-26.0% of dry matter (DM); r=0.76; P