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Corn crops require large amounts of resources that affect the environmental sustainability of dairy cow farming systems. The aim of the study was thus to investigate the effects of the replacement of corn silage (CS) with triticale silage (TS) by evaluating blood and productive parameters. The study lasted 7 weeks and involved two groups of 20 Italian Holstein Friesian dairy cows that were homogeneous in terms of parity (3±1.5), days in milk (DIM) (150±85.0), and daily milk production (26±4.6 kg). Chemical analysis of feeds was carried out weekly. Dry-matter intake was estimated daily. At the beginning and end of the trial, haematological, metabolic, and immunological parameters were analysed. At the same, time body weight and body condition score were measured. Milk characteristics were also analysed weekly. Statistical analysis was performed by ANOVA on data of the second sampling, and a non-parametric test was performed to analyse BCS. Regarding the haematological parameters in the two groups, only lymphocyte values were not in the normal range (2.86 and 2.50×109 L for CS and TS, respectively). Metabolic parameters were in the normal range except for blood ureic nitrogen (BUN; 13.65 and 14.04 mg dL−1), non-esterified fatty acids (NEFAs; 21.40 and 31.93 µmol L−1), and Cl (91.99 and 93.50 mmol L−1). Hair cortisol was low (0.94 and 0.91 pg mg−1), indicating the absence of stress signs, as confirmed by the results of other immunological parameters (serum lysozyme (SL), bactericidal activity (SBA), haptoglobin (HP), and oxygen free radicals (OFRs)). Statistical differences were not found either for haematological or biochemical parameters. The total replacement of CS with TS did not affect milk yield and composition. In conclusion, the replacement of CS by TS did not give rise to significant modifications in the parameters investigated and did not alter the health status of the animals, thus suggesting the feasibility of its introduction into the diet of mid-lactation dairy cows.

The interest of the scientific community in the effects of plant polyphenols on animal nutrition is increasing. These compounds, in fact, are ubiquitous in the plant kingdom, especially in some spontaneous plants exploited as feeding resources alternative to cultivated crops and in several agro-industry by-products. Polyphenols interact with rumen microbiota, affecting carbohydrate fermentation, protein degradation, and lipid metabolism. Some of these aspects have been largely reviewed, especially for tannins; however, less information is available about the direct effect of polyphenols on the composition of rumen microbiota. In the present paper, we review the most recent literature about the effect of plant polyphenols on rumen microbiota responsible for unsaturated fatty acid biohydrogenation, fiber digestion, and methane production, taking into consideration the advances in microbiota analysis achieved in the last 10 yr. Key aspects, such as sample collection, sample storage, DNA extraction, and the main phylogenetic markers used in the reconstruction of microbial community structure, are examined. Furthermore, a summary of the new high-throughput methods based on next generation sequencing is reviewed. Several effects can be associated with dietary polyphenols. Polyphenols are able to depress or modulate the biohydrogenation of unsaturated fatty acids by a perturbation of ruminal microbiota composition. In particular, condensed tannins have an inhibitory effect on biohydrogenation, whereas hydrolyzable tannins seem to have a modulatory effect on biohydrogenation. With regard to fiber digestion, data from literature are quite consistent about a general depressive effect of polyphenols on gram-positive fibrolytic bacteria and ciliate protozoa, resulting in a reduction of volatile fatty acid production (mostly acetate molar production). Methane production is also usually reduced when tannins are included in the diet of ruminants, probably as a consequence of the inhibition of fiber digestion. However, some evidence suggests that hydrolyzable tannins may reduce methane emission by directly interacting with rumen microbiota without affecting fiber digestion.

Dairy sheep systems are relevant for the economy of many rural areas of the Mediterranean Basin and the optimisation of their productive factors is necessary to improve their competitiveness and to reduce their environmental impact. The objective of this study was to assess, through a farm-scale life cycle assessment (LCA) approach, the potential of reducing environmental impacts on ewe milk of an innovative farming system (IF), based on the adoption of a precision feeding approach to improve milk production and quality, compared with a conventional farming system (CF) in dairy sheep farms in Tuscany region, Italy. The LCA analysis was carried out through a cradle-to-farm-gate LCA, comparing three conventional farms with three innovative farms, using 1 kg of fat protein corrected milk (FPCM) as a functional unit. The Small Ruminants Module of Nutritional Dynamic System (NDS) software was used to estimate methane emissions due to enteric fermentation. The introduction of precision feeding strategy reduced the environmental impacts of ewe milk as a consequence of the increased milk production efficiency (+50%). Indeed, the environmental impact of ewe milk was reduced in IF by 42% as the average of the impact categories being significantly different between the two farming systems.HighlightsPrecision feeding is recognised as a strategy to mitigate the environmental impacts of ruminant production.Dairy sheep innovative farms (IF), using a precision feeding approach, were compared with conventional farms (CF).Environmental impacts of ewe mik were assessed through an LCA approach and a mechanistic model for ruminant diet formulation and evaluation.Precision feeding improved milk production efficiency (+50) and lowered environmental impacts.Environmental impact of ewe milk was significantly reduced in IF by 42% in eight impact categories out of 15. Precision feeding is recognised as a strategy to mitigate the environmental impacts of ruminant production. Dairy sheep innovative farms (IF), using a precision feeding approach, were compared with conventional farms (CF). Environmental impacts of ewe mik were assessed through an LCA approach and a mechanistic model for ruminant diet formulation and evaluation. Precision feeding improved milk production efficiency (+50) and lowered environmental impacts. Environmental impact of ewe milk was significantly reduced in IF by 42% in eight impact categories out of 15.

In the Mediterranean area, semi-extensive mixed farming systems characterise the inland landscape and guarantee the maintenance of several agroecosystem services. Rationed and rotational grazing have been proposed as efficient agroecological practices for sustainable intensification. Previous studies have highlighted that, during spring, restricted access time to pasture of below four hours per day decreases herbage intake and milk production of rotationally stoked ewes. The aim of this study was to assess the effect of restricted access time on daily herbage intake and milk productivity of Sarda ewes under rotational grazing management in a real farm located in southern Tuscany. The entire flock of 145 lactating ewes was allotted two homogenous groups and rotationally stoked on a grass-legume mixed pasture and fed about 1.7 kg of DM ewe–1 d–1 of supplementation. Each group was then assigned to the following treatments: two hours per day of access time to pasture, from 10:00 to 12:00 CET, and four hours per day of access time to pasture, from 10:00 to 14:00 CET. Data on herbage yield and quality, dry matter intake and milk yield were collected from April 5 to May 10, 2018. The rotational grazing schedule was conducted allowing for abundant herbage and exploiting high-nutritive biomass of the upper horizon sward. The results of our on-farm experiment showed that restricting daily access time to pasture down two hours did not reduce the potential daily herbage intake and the milk performance of dairy ewes rotationally stocked on a mixed pasture in spring. Our study also highlighted the capacity of ewes to self-regulate the herbage intake in order to meet their energy requirements, when neutral detergent fibre is not a limiting factor. Our outcomes should encourage researchers and farmers to co-design further on-farm experiments. Highlights - The challenge lies in comparing data of dairy sheep productivity collected at real farm condition with previous data measured in Mediterranean research stations. - In this study, no difference in milk production was found between ewes allowed to graze two hours and four hours per day in spring. - The ewes’ herbage intake rate correlates positively with pasture quality and a mixed pasture with a high share of legumes led to a high intake rate. - We believe that the outcomes in this manuscript can contribute to increase knowledge about the sustainable management of small ruminant dairy farms in the contest of rural areas.

The hypothesis that condensed tannins have higher inhibitory effect on ruminal biohydrogenation than hydrolyzable tannins was tested. Condensed tannin extract from mimosa (CT) and hydrolyzable tannin extract from chestnut (HT) or their mixture (MIX) were incorporated (10%) into oil supplemented diets and fed to rumen fistulated sheep. Fatty acid and dimethyl acetal composition of rumen contents and bacterial biomass were determined. Selected rumen bacteria were analyzed by quantitative real time PCR. Lower ( P < 0.05) rumen volatile fatty acids concentrations were observed with CT compared to HT. Moreover, lower concentration ( P < 0.05) of Fibrobacter succinogenes, Ruminococcus flavefaciens, Ruminococcus albus, and Butyrivibrio proteoclasticus were observed with CT compared to HT. The extension of biohydrogenation of 18:2n-6 and 18:3n-3 did not differ among treatments but was much more variable with CT and MIX than with HT. The trans-/ cis-18:1 ratio in bacterial biomass was higher ( P < 0.05) with HT than CT. Thus, mimosa condensed tannins had a higher inhibitory effect on ruminal metabolism and biohydrogenation than chestnut hydrolyzable tannins.

Olive oil pomace (OOP) is a bio-waste rich in highly soluble polyphenols. OOP has been proposed as an additive in ruminant feeding to modulate rumen fermentations. Three groups of ewes were fed the following different diets: a control diet and two diets supplemented with OOP, obtained with a two-phase (OOP2) or three-phase (OOP3) olive milling process. Rumen liquor (RL) showed a higher content of 18:3 cis9 cis12 cis15 (α-linolenic acid, α-LNA) with OOP2 inclusion, and of 18:2 cis9 trans11 (rumenic acid, RA) with OOP3 inclusion. The overall composition of the RL microbiota did not differ among treatments. Significant differences, between control and treated groups, were found for six bacterial taxa. In particular, RL microbiota from animals fed OOPs showed a reduction in Anaerovibrio, a lipase-producing bacterium. The decrease in the Anaerovibrio genus may lead to a reduction in lipolysis, thus lowering the amount of polyunsaturated fatty acids available for biohydrogenation. Milk from animals fed OOP showed a higher content of 18:1 cis9 (oleic acid, OA) but the α-LNA concentration was increased in milk from animals treated with OOP2 only. Therefore, inclusion of OOP in ruminant diets may be a tool to ameliorate the nutritional characteristics of milk.

Agro-industrial by-products contain several secondary plant metabolites, such as polyphenols, tannins, saponins, and essential oils. The effects of these compounds on animal metabolism may vary significantly according to the dose, the chemical nature of the molecules, and the overall composition of the diet. In the Mediterranean area, the olive oil extraction is associated with 2 by-products: olive pomace and wastewater, both rich in polyphenols. In particular, wastewater may be further processed to obtain olive crude phenolic concentrate (OCPC). An experiment was carried out aiming to evaluate animal performance, milk fatty acid (FA) profile, diversity of rumen microbial population, and rumen liquor FA profile in dairy ewes fed diets containing extruded linseed (EL) and increasing doses of OCPC. Twenty-eight Comisana ewes in mid lactation were allotted to 4 experimental groups. The experiment lasted 5 wk after 3 wk of adaptation. Diets were characterized by lucerne hay administrated ad libitum and by 800 g/ewe and day of 4 experimental concentrates containing 22% of EL on dry matter and increasing dose of OCPC: 0 (L0), 0.6 (L0.6), 0.8 (L0.8), and 1.2 (L1.2) g of OCPC/kg of dry matter. Milk yield was daily recorded and milk composition was analyzed weekly. At the beginning and at the end of the experiment, samples of rumen liquor were collected to analyze FA profile, changes in rumen microbial population, and dimethylacetal (DMA) composition. The inclusion of OCPC did not affect milk yield and gross composition, whereas milk from L0.8 and L1.2 sheep contained higher concentrations of linoleic (+18%) and α-linolenic acid (+24%) and lower concentration of the rumen biohydrogenation intermediates. A similar pattern was observed for rumen liquor FA composition. No differences were found in the diversity of the rumen microbial population. Total amount of DMA did not differ among treatments, whereas significant differences were found in the concentration of individual DMA; in the diet with a higher amount of OCPC, DMA 13:0, 14:0, 15:0, and 18:0 increased, whereas DMA 16:0 decreased. Probably the presence of polyphenols in the diet induced a rearrangement of bacteria membrane phospholipids as a response to the rumen environment stimulus. Overall, the use of OCPC allowed a significant increase in the polyunsaturated FA content of milk, probably due to a perturbation of the rumen biohydrogenation process. Further studies are needed to understand the correlation between diet composition and the pattern of DMA in rumen liquor.

Tannins are bioactive compounds able to interfere with protein and lipid metabolism in the rumen, by forming undegradable complexes with dietary proteins and by modulating several bacterial activities, including the biohydrogenation of polyunsaturated fatty acids. The aim of this trial was to study the effect of dietary supplementation with chestnut hydrolysable tannin extract on ewes milk yield and quality. Ninety-six multiparous Sarda ewes in their mid-lactation phase were allotted to two homogeneous groups (control group, C group; group fed concentrate supplemented with chestnut tannin extract, CHE group), each of 48 animals, for a feeding trial. Animals of both groups grazed 8 h per day on the same pasture based on a mixture of Lolium multiflorum, Avena sativa and Trifolium repens (1:1:1). The two diets differed only in their concentrate supplement. The control group received 450 g/head per day of a concentrate feed without chestnut tannin extract, whereas the CHE group received 500 g/head per day of a concentrate feed formulated with the same ingredients of the control concentrate plus 80.0 g/kg DM of chestnut tannin extract. The amounts of concentrate offered to the animals of both groups were calculated in order to obtain isoproteic and isoenergetic dietary treatments considering the expected DM intake of animals. The inclusion of chestnut tannin in the concentrate resulted in a greater production of milk (+18.64%; P < 0.001). Moreover, no differences in casein fraction profile between milks from both groups were found while the casein index was greater (P = 0.034) in milk from ewes fed CHE than milk from ewes fed C. As regard fatty acid composition, milk from CHE group had a greater concentration of omega-3 fatty acids if compared to milk from C group (alpha-linolenic acid: 2.18 vs 2.57 g/100 g of total lipids in C and CHE group, respectively), whereas the percentage of CLA and of C18:1 trans11 in milk fat from CHE group was smaller (CLA: 2.20 vs 1.85 g/100 g of total lipids, in C and CHE group, respectively with P = 0.001; C18:1 trans11: 3.89 vs 3.57 g/100 g of total lipids in C and CHE group, respectively with P = 0.001). The use of practical doses of CHT in the diet of grazing ewes may improve the response to dietary linseed supplementation, resulting in milk with a greater concentration of alpha-linolenic acid.

In the human intestine, lipids are absorbed as sn-2 monoglycerides (sn-2, also named β-position), produced mainly by pancreatic lipases, which hydrolysate the triglyceride molecule in positions 1 and 3 (sn-1,3, α-position). The fatty acids esterified in sn-2 are thus preferentially absorbed, which means that the bioavailability of a single fatty acid is affected by its position on the triglyceride. This experiment is carried out with the milk used to make cheese applied in a study with 42 human volunteers. In that study the authors detected an improvement in the blood lipid profile. The aim of the present study was to examine the effectiveness of this kind of cheese in improving human health by studying how linseed supplementation affects the milk fatty acid composition of the 3 different triglyceride positions and thus the fatty acid bioavailability. The sn-2 were obtained by reacting total milk lipids with swine pancreatic lipase. The milk came from 24 sheep fed a control diet and 24 sheep fed a diet containing 200 g of extruded linseed per day. The sn-2 were separated by thin-layer chromatography. The fatty acid composition of total lipids and sn-2 was obtained by a gas chromatography-flame ionization detector apparatus equipped with a high polar 100 m length capillary column. The bioavailability of the fatty acids was evaluated by a putative preferential intestinal absorption index (PPIAi), where PPIAi0 indicated a disadvantageous nutritional condition and PPIAi0 indicated a preferential intestinal absorption. With regard to the fatty acid composition of triglycerides, the linseed group showed a significantly higher content of both linolenic acid and rumenic acid compared with the control. As a consequence of linseed supplementation, the linolenic and rumenic acid content esterified in the β-position increased greatly. This was highlighted by the PPIAi. The results of the present study suggest that the linolenic acid and conjugated linoleic acid affinity for lyso-phosphatidic acid acyl-transferase increased with its tissue availability.

The aim of the present study was to evaluate the effect of the inclusion of chestnut or quebracho tannin extracts in the diet of grazing ewes supplemented with soybean oil, on the blood plasma and milk fatty acid profile, milk quality traits and animal metabolic profile. Eighteen Comisana ewes at 172 ± 6 days in milking were allotted into 3 experimental groups. Diets were characterized by pasture ad libitum administered and by 800 g/head and day of 3 experimental concentrates containing 84.5 g of soybean oil/kg of DM and 52.8 g/kg DM of bentonite (Control diet) or 52.8 g/kg DM of chestnut tannin extract (hydrolysable tannins, CHE diet) or 52.8 g/kg DM of quebracho tannin extract (condensed tannins, QUE diet). The trial lasted 4 weeks after 15 days of adaptation to the feeding regimen. Milk yield was daily recorded while milk composition and blood parameters were weekly analysed. CHE and QUE did not affect the milk yield and composition. Casein Index was affected by diet and it was significant higher in milk from animals fed QUE (P 30 were affected by tannins: r was higher for QUE milk while k 20 increased regardless the kind of tannin. Blood parameters were not affected by tannins and the oxidative status of ewes, determined using MDA as indicator, did not present significant differences among groups, regardless the concentrates fed to animals. Fatty acid profile of blood plasma demonstrated that tannin extract, regardless the source, favored the accumulation of vaccenic acid ( trans-11 18:1) reducing the hematic concentration of stearic acid (18:0). Only few significant differences in milk fatty acid profile were found. In particular, rumenic acid ( cis -9, trans -11 18:2) increased when the concentrates contained polyphenols and the stronger effect is reached with QUE (P

Ruminants derived products have a prominent role in diets and economy worldwide; therefore, the capability to control the rumen microbial ecosystem, for ameliorating their quality, is of fundamental importance in the livestock sector. The aim of this study was to evaluate the effect of dietary supplementation with chestnut and quebracho tannins on microbial community and fatty acid profile, in the rumen fluid of dairy ewes. Multivariate analysis of PCR-DGGE profiles of rumen microbial communities showed a correlation among the presence of chestnut or quebracho in the diet, the specificButyrivibriogroup DGGE profiles, the increase in 18:3cis9,cis12, andcis15; 18:2cis9 andcis12; 18:2cis9 andtrans11; 18:2trans11 andcis15; and 18:1trans11 content, and the decrease in 18:0 concentration. Phylogenetic analysis of DGGE band sequences revealed the presence of bacteria representatives related to the generaHungatella,Ruminococcus, andEubacteriumand unclassified Lachnospiraceae family members, suggesting that these taxa could be affected by tannins presence in the diets. The results of this study showed that tannins from chestnut and quebracho can reduce the biohydrogenation of unsaturated fatty acids through changes in rumen microbial communities.

The aim of this study was to evaluate the fatty acid composition, lipolysis, lipid oxidation and volatile organic compounds (VOCs) in Colonnata lard from Large White (LW) or Cinta Senese (CS) pigs during one-year curing. CS lard contained a higher amounts of unsaturated fatty acids than LW one, due to the different rearing and feeding systems. Despite the higher lipolysis in CS backfat during the curing period, the rate of fatty acid and cholesterol oxidation was higher in LW. The amount of cholesterol oxidation products (COPs) and thiobarbituric acid reactive substances (TBARs) significantly decreased after 3 months of curing, regardless of the type of lard. VOCs composition of lard was affected by curing time, but not by breed. While volatile fatty acid oxidation products (mainly aldehydes) were present at the beginning of the curing time, subsequently other volatiles compounds (such as sulphur compounds and terpenes) that derived from ingredients used for lard production, increased in lard samples.

The interpretation of mutual relationship among milk fatty acids (FA) is not easy due to the high number of FA contained in milk fat and to the high degree of correlation among them. Multivariate analysis includes different statistical approaches that could help explaining complex pattern of variables. In this study, Multivariate Factor Analysis (MFA) was used to decompose the correlation matrix of 47 FA and milk production traits (milk yield and protein and fat content) measured in 300 Italian Holstein Friesian cows reared in the North of Italy in 23 commercial dairy farms, representative of the intensive dairy system. MFA was able to extract seven latent factors with specific biologic meaning: secretion of Long Chain FA (K LCFA ), mammary FA de novo synthesis (K m ), rumen biohydrogenation (K bh ), synthesis of odd chain FA (K o ), synthesis of branched chain FA (K b ), mammary desaturation activity (K d ), milk yield (K my ). According to the pattern of communalities of the factor analysis, C18:3c9c12c15 was the only FA, along with C18:2t11c15, to be uncorrelated with the other variables and it seemed to be excluded by the metabolic pattern described by the seven factors. The desaturation products of the SCD enzyme were independently associated to three latent factors, suggesting new insights in the regulation of SCD activity. Factors were considered as new quantitative phenotypes related to prominent features of milk FA profile. With the aim of evaluating the feeding regimen and animal effects, latent factors were analysed with a mixed model, which considered the fixed effect of lactation stage, parity, some feeding regimen characteristics and the random effect of bull. Lactation stage significantly affected K m and K my factors. In perspective, the seven factors extracted by applying MFA analysis to milk FA composition could be considered as new and more informative traits to test the effect of endogenous and exogenous variation factors.

In order to examine whether olive pomace (OP), the mean by-product of olive oil extraction, could be included in the animal diet, its effect on the raw mixture and sausages made from meat from OP-fed Cinta Senese swine was tested by comparing it with a diet supplemented with high oleic sunflower oil (SO) and a control diet (C). Proximate composition, pH, color, total culturable bacteria, lactic acid bacteria (LAB) and lipid oxidation were evaluated in both the raw mixture and sausages. The aroma profile was also evaluated in sausages. Olive pomace affected the fatty acid composition of the raw mixture and strongly limited the lipid peroxidation of sausages, probably due to the synergistic action of 3,4-DHPEA and α-tocopherol. Olive pomace selectively promoted LAB growth, and protected the raw mixture and sausages from discoloration. The diet also affected the content of volatile organic compounds thus enabling OP sausages to be distinguished from other sausages. Practical applications: The protection of foods against lipid peroxidation is a very important aspect in terms of their quality. Achieving this naturally is a high priority for consumers, as there is an increasing demand for "low impact" and "environment-safe" production processes. The approach proposed in the present study is aimed at meeting both these objectives. Our findings demonstrate that the inclusion of olive pomace in the swine diet effectively slowed down the lipid oxidation in the sausages. The strategy we propose also meets both economic and ecological goals. Olive pomace is the main by-product of olive oil spinneret, and its re-use in another spinneret is a cost-effective way of improving the sustainability of the production process.