Ecosystem Services of Grazed Grasslands in the Flooding Pampa

The Flooding Pampa grasslands are the last remnant of the Rio de la Plata grasslands in Argentina.Anthropo-genic interventions have led to severe degradation and,as a result,the ecosystem services provided by the grass-lands are declining,in terms of provisioning,regulating,and supporting services.We synthesized the existing literature on the ecosystem goods and services provided by these grasslands under grazing in different conditions and conservation status.We found that plant and animal diversity and primary production are the most studied ecosystem services,while climate regulation,water supply,nutrient cycling,meat production and erosion control,in that order,are less studied.Cultural services are under-researched.Continuous grazing and glyphosate spraying are the main drivers of grassland degradation.Controlled grazing and conservative stocking rates have been shown to reverse degradation and demonstrate that livestock production is compatible with ecosystem conserva-tion by maintaining regulating and provisioning services.As these management strategies are poorly integrated,improving their implementation will require important changes in farmers’decisions and the development of policies that create the economic conditions for this to happen.Research is needed to understand the conditions that prevent the knowledge generated from being transferred to producers and translated into practices that would improve the provision of ecosystem services.

Phenotypic and genotypic background underlying variations in fatty acid composition and sensory parameters in European bovine breeds

Background： Consuming moderate amounts of lean red meat as part of a balanced diet valuably contributes to intakes of essential nutrients, in this study, we merged phenotypic and genotypic information to characterize the variation in lipid profile and sensory parameters and to represent the diversity among 15 cattle populations. Correlations between fat content, organoleptic characteristics and lipid profiles were also investigated. Methods： A sample of 436 largely unrelated purebred bulls belonging to 15 breeds and reared under comparable management conditions was analyzed. Phenotypic data -including fatness score, fat percentage, individual fatty acids （FA） profiles and sensory panel tests- and genotypic information from 11 polymorphisms was used. Results： The correlation coefficients between muscle total lipid measurements and absolute vs. relative amounts of polyunsaturated FA （PUFA） were in opposite directions. Increasing carcass fat leads to an increasing amount of FAs in triglycerides, but at the same time the relative amount of PUFAs is decreasing, which is in concordance with the negative correlation obtained here between the percentage of PUFA and fat measurements, as well as the weaker correlation between total phospholipids and total lipid muscle content compared with neutral lipids. Concerning organoleptic characteristics, a negative correlation between fiavour scores and the percentage of total PUFA, particularly to n-6 fraction, was found. The correlation between juiciness and texture is higher than with flavour scores. The distribution of SNPs plotted by principal components analysis （PCA） mainly reflects their known trait associations, although influenced by their specific breed allele frequencies. Conclusions： The results presented here help to understand the phenotypic and genotypic background underlying variations in FA composition and sensory parameters between breeds. The wide range of traits and breeds studied, along with the genotypic information on polymorphisms previously associated with different lipid traits, provide a broad characterization of beef meat, which allows giving a better response to the variety of consumers＇ preferences. Also, the development and implementation of low-density SNP panels with predictive value for economically important traits, such as those summarized here, may be used to improve production efficiency and meat quality in the beef industry.

Intake, Energy Expenditure and Methane Emissions of Grazing Dairy Cows at Two Pre-Grazing Herbage Masses

A grazing experiment was undertaken to assess the effects of two levels of herbage mass (HM) on herbage DM intake (DMI), fat and protein corrected milk yield (FPCM), grazing behaviour, energy expenditure (HP), and methane emissions (CH4) of grazing dairy cows in spring. Treatments were a low HM (1447 kg DM/ha;LHM) or a high HM (1859 kg DM/ha;HHM). Pasture was composed mainly of cocksfoot (Dactylis glomerata) and lucerne (Medicago sativa), offered at a daily herbage allowance of 30 kg DM/cow, above 5 cm. Eight multiparous Holstein cows were used in a 2 × 2 Latin Square design in two 10-day periods. Despite the differences in pre-grazing HM between treatments, OM digestibility was not different (P = 0.28). Herbage mass did not affect DMI or FPCM. Grazing time was not different between treatments, but cows had a greater bite rate when grazing on LHM swards. However, HP did not differ between treatments. Daily methane emission (per cow), methane emission intensity (per kg FPCM) and methane yield (as percentage of gross energy intake) were not different. The lack of effect of the amount of pre-grazing HM on energy intake, confirms that the difference between HM treatments was beyond the limits that impose extra energy expenditure during grazing.

Chemical Composition and Antioxidant Activity of Date Seeds from Different Tunisian Date Palm Cultivars

Chemical composition,polyphenolic and flavonoid contents,and antioxidant activity were determined in date seeds derived from four Tunisian date palm(Phoenix dactylifera)cultivars namely:Goundi,Chekena,Mnekher and Remtha.Sodium and potassium contents in date seeds were determined by flame photometry,phenolic compounds by the Folin-Ciocalteu method,flavonoids by colorimetric quantification,and the antioxidant activity by the DPPH free radical scavenging method.Crude protein content varied widely(p<0.001)between date seed varieties and ranged from 3.95(Goundi)to 7.51%DM(Chekena).No significant differences(p>0.001)were detected between seed varieties for their dry matter(DM)and ash contents.However,sodium,potassium and phosphorus varied widely(p<0.001)between varieties.The highest phenolic content(p<0.001)was observed in Goundi(39.4 mg gallic acid equivalent(GAE)/g DM)and Remtha(36.6 mg GAE/g DM)seed varieties.Likewise,Goundi had the highest(p<0.001)flavonoid content(16.4 mg quercetin equivalent(QE)/g DM)and antioxidant activity(1,807μM Trolox equivalent antioxidant capacity(TEAC)/g DM);however the lowest values(p<0.001)of phenolic(19.2 mg GAE/g DM),flavonoid(8.8 mg QE/g DM)and antioxidant activity(682μM TEAC/g DM)were observed for Chekena seeds.Further studies are needed to verify the potential of date seeds as alternative for animal nutrition.

Effect of fosfomycin,Cynara scolymus extract,deoxynivalenol and their combinations on intestinal health of weaned piglets

Weaning is a challenging stage of pig farming.Animals undergo environmental,social and dietary changes leading to weaning stress syndrome.In order to compensate for the detrimental effects of weaning stress,antibiotics and natural extracts are used as feed additives,sometimes without fully understanding the interactions between them or even with low concentrations of mycotoxins that are frequently present in feed.The aim of this study was to evaluate the effect of fosfomycin(FOS),Cynara scolymus extract(CSE),deoxynivalenol(DON) and their combined administration on intestinal health of weaned piglets.The experiment was designed as a 2×2×2 factorial arrangement with 3 factors(FOS,CSE and DON treatments),2 levels each(presence and absence) and 3 repeats.Weaned piglets(n=24)were randomly divided in groups to receive the different treatments,namely DON administered in diet(50 μg/kg BW),FOS administered into the drinking water(30 mg/kg BW),CSE administered in diet(15 mg/kg BW) and all their combinations.After 15 d,the animals were euthanized and gastrointestinal tract samples were immediately taken to evaluate gastrointestinal pH,Enterobacteriaceae to lactic acid bacteria(E:L) ratio,volatile fatty acid(VFA) concentrations,disaccharidase(lactase,sucrase and maltase)activity,histology(intestinal absorptive area [IAA] and goblet cells count) and mucus ability to adhere pathogenic Escherichia coli.From our results,FOS and CSE treatments,individually or combined,produced a lower E:L ratio,an enhanced production of butyrate,increased disaccharidase activity(particularly maltase),and a greater IAA and goblet cells count along with an increase in pathogenic bacteria adherence to intestinal mucus.Deoxynivalenol did not show interactions with the other factors and its administration produced decreases on VFA,disaccharidase activity and goblet cells count.In conclusion,weaning piglets receiving diets containing FOS,CSE or both exhibited evident beneficial intestinal effects compared to animals receiving diets free from these compounds.On the contrary,the presence of DON at sub-toxic concentrations produced detrimental effects on intestinal health.The knowledge of the physiological and pathological gut changes produced by these compounds contributes to understand their potential productive consequences.

Agronomic assessment of two populations of intermediate wheatgrass—Kernza^(®)(Thinopyrum intermedium)in temperate South America

Background Kernza®intermediate wheatgrass is a perennial grain and forage crop that can provide several ecosystem services.Major research efforts focused on Kernza have taken place in high latitudes.The goal of this study was to evaluate,for the first time,the agronomic performance of Kernza in a low-latitude region with mild winters.Methods A KS-cycle 4 Kernza population(A)was planted in spring in Wisconsin,USA,and selected in one cycle for lower vernalization requirements,obtaining a new population(B).These two populations,at three nitrogen(N)fertilization rates,were evaluated in a full factorial,completely randomized field experiment in Uruguay over 2 years.Results The populations were similar in grain yields and flowering time in the 1st year,but population B had 63%lower grain yield in the 2nd year and 20%lower forage yield throughout the experiment.Increasing the N rate to 160 kg ha−1 led to a 63%increase in grain yield and 28%increase in forage yield across populations.Forage yields and nutritive values were similar to those reported in the northern hemisphere.However,grain yields for both the 1st(316 kg ha−1)and 2nd year(41 kg ha−1)were lower due to reduced flowering and weed competition.Conclusions Expansion of Kernza to lower-latitude regions will require further breeding to improve reproductive performance.