Nutritive evaluation and milk quality of including of tomato or olive by-products silages with sunflower oil in the diet of dairy goats

Using fresh vegetable waste from Chinese traditional wet markets as animal feed: Material feasibility and utilization potential

To develop new animal feed sources and establish a sustainable food upcycling system, the material feasibility and feeding potential of fresh vegetable waste (FVW) were clarified in this study. First, the FVW output of wet markets in Hangzhou, China was tracked and predicted. The results showed that the retail waste ratio of FVW in wet markets reached 9.3 %, predicting that China's FVW will reach 9034 kt in 2030. Second, the study revealed that the nutritive value of FVW was comparable to that of traditional alfalfa feed, suitable for use as animal feed. However, we found a high probability of microbial contamination. Therefore, FVW should have stricter classification and collection methods. Under this premise, the feeding utilization potential of FVW in wet markets is large. In 2030, the crude protein content may replace 2737 kt of alfalfa, saving 7.7 E + 08 m3 of water and 75,018 ha of land.

The Dietary Inclusion of Ensiled Olive Cake Increases Unsaturated Lipids in Milk and Alters the Expression of Lipogenic Genes in Mammary and Adipose Tissue in Goats

This study aimed to evaluate the effect of the dietary inclusion of ensiled OC on milk yield, composition, fatty acid (FA) profile, and the expression of selected genes involved in lipid metabolism in the udder and adipose tissue of goats. Seventy-two Damascus dairy goats in mid-lactation were assigned randomly to three iso-nitrogenous and iso-energetic diets containing 0, 10, and 20% of ensiled OC as a replacement of forage (OC0, OC10, and OC20, respectively) for 42 days. During weeks 5 and 6 of the trial, dry matter intake, milk yield, milk composition, and FA profiles were recorded, while mammary and perirenal adipose tissue samples were also collected from six animals per treatment from the OC0 and OC20 groups for gene expression analysis. No significant differences were observed among groups concerning milk yield, 4% fat-corrected milk, fat, or protein yield (kg/d). In contrast, the milk fat percentage was gradually increased with increasing OC inclusion rates in the diets, while milk protein percentages were elevated in both OC groups but significantly only in the milk of the OC20 group. The content of FA between C4:0 to C16:0 was reduced, while mono-unsaturated FA (MUFA) concentration was enhanced in the goat milk of OC groups. The OC feeding treatment was associated with the increased mammary expression of SLC2A1 (p < 0.05), VLDLR (p < 0.01), FABP3 (p < 0.01), and elevated SLC2A1 (p < 0.05) and FASN (p < 0.01) gene expression in the adipose tissue of goats fed the OC20 diet. Overall, OC can be used in goats' diets as a forage replacement, at least in the inclusion rate of 20% DM, since this could increase the milk protein and fat percentage and enrich its content with beneficial for human health lipids without adversely affecting milk production traits.

Rumen microbial degradation of bromoform from red seaweed (Asparagopsis taxiformis) and the impact on rumen fermentation and methanogenic archaea

BACKGROUND

The red macroalgae Asparagopsis is an effective methanogenesis inhibitor due to the presence of halogenated methane (CH4) analogues, primarily bromoform (CHBr3). This study aimed to investigate the degradation process of CHBr3 from A. taxiformis in the rumen and whether this process is diet-dependent. An in vitro batch culture system was used according to a 2 × 2 factorial design, assessing two A. taxiformis inclusion rates [0 (CTL) and 2% DM diet (AT)] and two diets [high-concentrate (HC) and high-forage diet (HF)]. Incubations lasted for 72 h and samples of headspace and fermentation liquid were taken at 0, 0.5, 1, 3, 6, 8, 12, 16, 24, 48 and 72 h to assess the pattern of degradation of CHBr3 into dibromomethane (CH2Br2) and fermentation parameters. Additionally, an in vitro experiment with pure cultures of seven methanogens strains (Methanobrevibacter smithii, Methanobrevibacter ruminantium, Methanosphaera stadtmanae, Methanosarcina barkeri, Methanobrevibacter millerae, Methanothermobacter wolfei and Methanobacterium mobile) was conducted to test the effects of increasing concentrations of CHBr3 (0.4, 2, 10 and 50 µmol/L).

RESULTS

The addition of AT significantly decreased CH4 production (P = 0.002) and the acetate:propionate ratio (P = 0.003) during a 72-h incubation. The concentrations of CHBr3 showed a rapid decrease with nearly 90% degraded within the first 3 h of incubation. On the contrary, CH2Br2 concentration quickly increased during the first 6 h and then gradually decreased towards the end of the incubation. Neither CHBr3 degradation nor CH2Br2 synthesis were affected by the type of diet used as substrate, suggesting that the fermentation rate is not a driving factor involved in CHBr3 degradation. The in vitro culture of methanogens showed a dose-response effect of CHBr3 by inhibiting the growth of M. smithii, M. ruminantium, M. stadtmanae, M. barkeri, M. millerae, M. wolfei, and M. mobile.

CONCLUSIONS

The present work demonstrated that CHBr3 from A. taxiformis is quickly degraded to CH2Br2 in the rumen and that the fermentation rate promoted by different diets is not a driving factor involved in CHBr3 degradation.

Early life supplementation with a natural blend containing turmeric, thymol, and yeast cell wall components to optimize rumen anatomical and microbiological development and productivity in dairy goats

Ruminants are born with an anatomically, microbiologically, and metabolically immature rumen. Optimizing the rearing of young ruminants represent an important challenge in intensive dairy farms. Therefore, the objective of this study was to evaluate the effects of dietary supplementation of young ruminants with a plant extract blend containing turmeric, thymol, and yeast cell wall components such as mannan oligosaccharides and β-glucans. One hundred newborn female goat kids were randomly allocated to 2 experimental treatments, which were unsupplemented (CTL) or supplemented with the blend containing plant extracts and yeast cell wall components (PEY). All animas were fed with milk replacer, concentrate feed, and oat hay, and were weaned at 8 wk of age. Dietary treatments lasted from wk 1 to 22 and 10 animals from each treatment were randomly selected to monitor feed intake, digestibility, and health-related indicators. These latter animals were euthanized at wk 22 of age to study the rumen anatomical, papillary, and microbiological development, whereas the remaining animals were monitored for reproductive performance and milk yield during the first lactation. Results indicated that PEY supplementation did not lead to feed intake or health issues because PEY animals tended to have a higher concentrate intake and lower diarrheal incidence than CTL animals. No differences between treatments were noted in terms of feed digestibility, rumen microbial protein synthesis, health-related metabolites, or blood cell counts. Supplementation with PEY promoted a higher rumen empty weight, and rumen relative proportion to the total digestive tract weight, than CTL animals. This was accompanied with a higher rumen papillary development in terms of papillae length and surface area in the cranial ventral and caudal ventral sacs, respectively. The PEY animals also had higher expression of the MCT1 gene, which is related to volatile fatty acid absorption by the rumen epithelium, than CTL animals. The antimicrobial effects of the turmeric and thymol could explain the decreased the rumen absolute abundance of protozoa and anaerobic fungi. This antimicrobial modulation led to a change in the bacterial community structure, a decrease in the bacteria richness, and to the disappearance (i.e., Prevotellaceae_UCG-004, Bacteroidetes_BD2-2, Papillibacter, Schwartzia, and Absconditabacteriales_SR1) or decline of certain bacterial taxa (i.e., Prevotellaceae_NK3B31_group, and Clostridia_UCG-014). Supplementation with PEY also decreased the relative abundance of fibrolytic (i.e., Fibrobacter succinogenes and Eubacterium ruminantium) and increased amylolytic bacteria (Selenomonas ruminantium). Although these microbial changes were not accompanied with significant differences in the rumen fermentation, this supplementation led to increased body weight gain during the preweaning period, higher body weight during the postweaning period, and higher fertility rate during the first gestation. On the contrary, no residual effects of this nutritional intervention were noted on the milk yield and milk components during the first lactation. In conclusion, supplementation with this blend of plant extracts and yeast cell wall component in early life could be considered as a sustainable nutritional strategy to increase body weight gain and optimize the rumen anatomical and microbiological development in young ruminants, despite having minor productive implications later in life.

Evaluating the effect of phenolic compounds as hydrogen acceptors when ruminal methanogenesis is inhibited in vitro – Part 2. Dairy goats

Most mitigation strategies to reduce enteric methane (CH₄) production in the rumen induce an excess of rumen dihydrogen (H₂) that is expelled and consequently not redirected to the synthesis of metabolites that can be utilised by the ruminant. We hypothesised that phenolic compounds can be potential H₂ acceptors when added to the diet, as they can be degraded to compounds that may be beneficial for the animal, using part of the H₂ available when ruminal methanogenesis is inhibited. We performed four in vitro incubation experiments using rumen inoculum from Murciano-Granadina adult goats: Experiment 1 examined the inhibitory potential of Asparagopsis taxiformis (AT) at different concentrations (0, 1, 2, 3, 4 and 5% of the substrate on a DM basis) in 24 h incubations; Experiment 2 investigated the effect of a wide range of phenolic compounds (phenol, catechol, resorcinol, hydroquinone, pyrogallol, phloroglucinol, gallic acid and formic acid) at different doses (0, 2, 4, and 6 mM) on rumen fermentation for 24 h; Experiment 3 evaluated the combined effect of each phenolic compound at 6 mM with AT at 2% DM in sequential batch cultures for 5 days; and Experiment 4 examined the dose-response effect of phloroglucinol at different concentrations (0, 6, 16, 26 and 36 mM) combined with AT in sequential batch cultures for 5 days. Results from Experiment 1 confirmed that AT at 2% DM substantially inhibited CH₄ production while significantly increasing H₂ accumulation and decreasing the acetate:propionate ratio. Results from Experiment 2 showed that phenolic compounds did not negatively affect rumen fermentation at any dose. In Experiment 3, each phenolic compound at 6 mM combined with AT at 2% DM inhibited CH₄ production. Phloroglucinol numerically decreased H₂ accumulation and significantly increased total gas production (TGP), volatile fatty acid (VFA) production and the acetate:propionate ratio. In Experiment 4, phloroglucinol at increasing doses supplemented with AT at 2% DM significantly decreased H₂ accumulation and the abundances of archaea, protozoa and fungi abundances, and increased TGP, total VFA production and the acetate:propionate ratio in a dose-dependent way. In conclusion, combined treatment with AT and phloroglucinol was successful to mitigate CH₄ production while preventing the accumulation of H₂, leading to an increase in acetate and total VFA production and therefore an improvement in rumen fermentation in goats.

Grape, Pomegranate, Olive, and Tomato By-Products Fed to Dairy Ruminants Improve Milk Fatty Acid Profile without Depressing Milk Production

The continuous increase in the cost of feeds and the need to improve the sustainability of animal production require the identification of alternative feeds, such as those derived from the agro-industrial sector, that can be effectively used for animal nutrition. Since these by-products (BP) are sources of bioactive substances, especially polyphenols, they may play an important role as a new resource for improving the nutritional value of animal-derived products, being effective in the modulation of the biohydrogenation process in the rumen, and, hence, in the composition of milk fatty acids (FA). The main objective of this work was to evaluate if the inclusion of BP in the diets of dairy ruminants, as a partial replacement of concentrates, could improve the nutritional quality of dairy products without having negative effects on animal production traits. To meet this goal, we summarized the effects of widespread agro-industrial by-products such as grape pomace or grape marc, pomegranate, olive cake, and tomato pomace on milk production, milk composition, and FA profile in dairy cows, sheep, and goats. The results evidenced that substitution of part of the ratio ingredients, mainly concentrates, in general, does not affect milk production and its main components, but at the highest tested doses, it can depress the yield within the range of 10-12%. However, the general positive effect on milk FA profile was evident by using almost all BP at different tested doses. The inclusion of these BP in the ration, from 5% up to 40% of dry matter (DM), did not depress milk yield, fat, or protein production, demonstrating positive features in terms of both economic and environmental sustainability and the reduction of human-animal competition for food. The general improvement of the nutritional quality of milk fat related to the inclusion of these BP in dairy ruminant diets is an important advantage for the commercial promotion of dairy products resulting from the recycling of agro-industrial by-products.

Potential of Agroindustrial By-Products to Modulate Ruminal Fermentation and Reduce Methane Production: In Vitro Studies

The effects of including wine lees (WL), exhausted olive cake (EOC) and a 1:1 mixture of EOC and tomato pomace (EOCTP) in diets for fattening ruminants on in vitro fermentation parameters and CH4 production were analysed. Ten diets were studied, containing either none of the tested by-products (control), or 6.0, 12.0 or 18.0% of WL, EOC and ECOTP formulated to have similar protein and fiber content. Diets were incubated in vitro with sheep ruminal fluid to measure gas production kinetics and fermentation parameters. Increasing the level of WL, EOC and EOCTP decreased linearly (p ≤ 0.009) the potential gas production, but other gas production parameters were unaffected (p > 0.05), excepting that EOCTP increased the gas production rate. No differences (p ≥ 0.0.05) among diets were observed in total volatile fatty acid (VFA) production at 24 h of incubation for EOC and EOCTP, but NH3-N concentration decreased (p ≤ 0.003). In contrast, WL at 12.0 and 18.0% decreased (p < 0.05) total VFA production and increased the acetate/propionate ratio (p < 0.05). None of the by-products had an effect on CH4 production (p ≥ 0.0.05). Results indicate that EOC and EOCTP could be included up to 18.0% in fattening diets, but lower levels of WL are recommended.

Generation of fruit and vegetable wastes in the farmers' market and its influencing factors: A case study from Hangzhou, China

There remains little understanding of fruit and vegetable wastage and the influencing factors within retail. This study aimed to examine the processes contributing to vegetable and fruit wastage in traditional farmers' markets widely existing in China, Thailand, and South Korea, with the farmers' market in Hangzhou, China used as a case study. Questionnaires and follow-up surveys were conducted with the market stakeholders (market managers, retailers, and market cleaners) from April 2021 to January 2022. The results showed that the categories of discarded fruits and vegetables were related to their sales varieties, with leaf vegetables and bananas constituting the categories of vegetables and fruit with the most daily wastage. Wastage of fruits and vegetables mostly occurred in the morning. However, there was seasonal variation in fruit and vegetable wastage, with wastage in summer exceeding that in winter. The quantity of fruit and vegetable wastage was related to the size of the farmers' market. The volume of sales was also shown to be positively correlated to wastage. The analysis showed that the rank of factors influencing fruit and vegetable sales was: market service community size > appearance of fruits and vegetables > weather > market environment > fruit and vegetable price > fruit and vegetable origin. Finally, most stakeholders were motivated to reduce wastage, with their motivations including ethics, legal requirements, and economic reasons. The results of this study can act as an important reference for improving the management fruit and vegetable waste.

Resource potential and global warming potential of fruit and vegetable waste in China based on different treatment strategies

Fruit and vegetable waste (FVW) contains rich resources that can be recovered by methods such as incineration, anaerobic digestion to generate heat energy, biogas, and preservation by ensiling. However, a horizontal comparison of the resource potential and environmental impact of different recycling methods employed for FVW has not been conducted. This study quantifies and computes the recycling potential and global warming potential (GWP) of anaerobic digestion, ensiling, and incineration of the FVW generated during primary production in China. First, a gray model was employed to estimate the FVW output in 2030, based on the FVW produced between 2002 and 2017. Next, the resource potential and GWP of anaerobic digestion, incineration, and ensiling were evaluated. Finally, an optimization method was utilized to analyze possible strategies of FVW recycling in 2030. Results indicate that FVW output in China is expected to increase to 170 Mt by 2030, highlighting the need for efficient treatment options. Further, the resource potential and GWP of different waste treatment strategies were notably different. The recycling potential of ensiling was the highest at 1950 MJ/t; while the GWP of anaerobic digestion was the lowest at -31 kg CO2eq. An optimization analysis suggested that the optimal target of 100% would be attained if all FVW is ensiled in 2030. The study provides a basis for informed technical decision-making related to FVW recycling options in the future.

Inclusion of Cocoa Bean Shell in the Diet of Dairy Goats: Effects on Milk Production Performance and Milk Fatty Acid Profile

The use of agro-industrial by-products in animal nutrition is a promising strategy to reduce the food-feed competition, the diet cost at farm level and the environmental impact of animal-derived food production. In this study, the suitability of cocoa bean shell (CBS), a by-product of the cocoa industry, as a feed ingredient in the diet of dairy goats was evaluated, with a focus on the related implications on feed intake, milk yield, milk main constituents, and fatty acid (FA) profile of milk fat. Twenty-two Camosciata delle Alpi goats were divided into two balanced groups. All the goats were fed mixed hay ad libitum. The control group (CTRL; n = 11) also received 1.20 kg/head × day of a commercial concentrate, while in the experimental group (CBS; n = 11) 200 g of the CTRL concentrate were replaced by the same amount of pelleted CBS. The total dry matter intake of the goats was reduced by the dietary inclusion of CBS (P ≤ 0.01). The milk yield, as well as the milk fat, protein, and casein contents and yields were unaffected by the treatment. Milk from the CBS-fed goats showed decreased urea content when compared to the CTRL group (P ≤ 0.001). Milk from the CBS group of goats also showed increased concentrations of total branched-chain FA (both iso and anteiso forms; P ≤ 0.001) and total monounsaturated FA (P ≤ 0.05), as well as a decreased ∑ n6/∑ n3 FA ratio (P ≤ 0.05). De novo saturated FA, total polyunsaturated FA, total conjugated linoleic acids, and the majority of ruminal biohydrogenation intermediates remained unaffected by the dietary treatment. These results suggest that CBS can be strategically used as an alternative non-conventional raw material in diets intended for lactating goats, with no detrimental effects on their milk production performance. The use of CBS in goat nutrition may be hindered by the presence of theobromine, a toxic alkaloid. Special attention is needed by nutritionists to avoid exceeding the theobromine limits imposed by the current legislation. Detheobromination treatments are also suggested in literature to prevent toxic phenomena.

Effect of Olive Cake and Cactus Cladodes Incorporation in Goat Kids' Diet on the Rumen Microbial Community Profile and Meat Fatty Acid Composition

Simple Summary

Throughout the world, the ruminant diet is based on conventional feedstuffs, which their price constantly fluctuates, and their use presents a concurrence to human nutrition. The use of alternative feed resources seems to be a solution to reduce charges and diversify ruminants’ diet. Olive cake and cactus cladodes are two alternative feed resources that are recommended to be used in ruminant feed. However, their effect on the bacterial community of ruminants is not widely investigated. This study aims to evaluate the effect of olive cake and cactus cladodes on the ruminal microbial ecosystem and meat fatty acids of goat kids. The incorporation of these feedstuffs did not change the bacterial abundance and diversity. Goat kids’ rumen liquor seemed to be able to adapt to alternative feed resources incorporation. The introduction of olive cake and cactus cladodes slightly affect meat fatty acids without a negative effect. Thus, ruminants seem to have the ability to adapt to the alternative feed resources digestion, and their use as a feed could diversify feed and reduce feed cost.

Abstract

The olive cake (OC) and the cactus cladodes (CC) are two alternative feed resources widely available in the southern Mediterranean region that could be used in ruminants’ diet. Their impact on the rumen bacterial ecosystem is unknown. This work aims to evaluate their effects on the microbial community and meat fatty acids of goat’s kids. Forty-four goat kids were divided into four groups receiving diets with conventional concentrate, or 35% OC, or 30% CC, or 15% OC, and 15% CC. After 3 months, these animals were slaughtered, and the rumen liquor and longissimus dorsi and semimembranosus muscles samples were collected. Animals receiving a control diet had rumen liquor with high acidity than test groups (p < 0.001). Test rumen liquor was more adapted to digest efficiently their matching diet than control liquor (p < 0.05). These feedstuffs did not affect rumen bacteria abundance and alpha diversity (richness, evenness, and reciprocal Simpson indexes), and these results were confirmed by beta-diversity tests (NMDS plot, HOMOVA, PERMANOVA). The test diets slightly affected the individual fatty acids of meat (p < 0.05) without effect on fatty acids summaries, indexes, and ratios. Thus, these alternative feed resources could take place in goat kids’ diet to diversify their feed and to reduce feed costs.

A novel ammoniation treatment of barley as a strategy to optimize rumen pH, feed degradability and microbial protein synthesis in sheep

BACKGROUND

Meeting the energy and nitrogen (N) requirements of high-performing ruminants at the same time as avoiding digestive disturbances (i.e. rumen acidosis) is a key priority in ruminant nutrition. The present study evaluated the effect of a cereal ammoniation treatment, in which barley grains are combined with urea and enzymes that catalyze the conversion of urea to ammonia to optimize rumen function. Twelve rumen cannulated sheep were randomly divided into two groups and fed a diet containing 60% of ammoniated barley (AMM) or untreated barley supplemented with urea (CTL) to investigate the impact on rumen fermentation and feed utilization.

RESULTS

AMM had higher total N content and effective rumen degradable N than untreated barely. AMM sheep had a consistently higher rumen pH throughout the day (6.31 versus 6.03) and tended to have a lower post-prandial ammonia peak and higher acetate molar proportion (+5.1%) than CTL sheep. The rumen environment in AMM sheep favored the colonization and utilization of agro-industrial by-products (i.e. orange pulp) by the rumen microbes leading to a higher feed degradability. AMM sheep also had higher total tract apparent N digestibility (+21.7%) and urinary excretion of purine derivatives (+34%), suggesting a higher N uptake and microbial protein synthesis than CTL sheep.

CONCLUSION

The inclusion of AMM in the diet of ruminants represents a valid strategy for maintaining rumen pH within a physiological range and improving N utilization by the rumen microbes, which could have positive effects on the health and productivity of animals in intensive production systems. These findings warrant further studies under conventional farm conditions. © 2021 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

Supplementing the Diet of Dairy Goats with Dried Orange Pulp throughout Lactation: I. Effect on Milk Performance, Nutrient Utilisation, Blood Parameters and Production Economics

Simple Summary

Dried orange pulp can conveniently replace cereals in ruminant diets; however, no published reports have considered a similar substitution for the goat diet throughout lactation. Therefore, in this study, we evaluated the effects of cereal replacement (40% and 80%) by dried orange pulp in the diet of Payoya breed goats during the entire lactation period (180 days) on milk yield and composition, blood metabolites and production economics. Also evaluated, in mid-lactation, were the nutrient utilisation and ruminal fermentation of the dried orange pulp diets. Milk production and gross composition did not change in goats fed diets that included dried orange pulp. A decrease in nitrogen availability and retention was observed, while an increase detected in the digestibility of cellulose likely boosted rumen microbial protein synthesis. No pathological effects of dried orange pulp supplementation were detected in blood metabolites. The partial substitution of cereals for dried orange pulp reduced costs and raised economic profits. In conclusion, the partial replacement of cereals by dried orange pulp is a profitable and healthy nutritional strategy in dairy goats that does not compromise their productivity and is suitable for the entire lactation period.

Abstract

Dried orange pulp (DOP) can be incorporated into ruminant diets, but no reports have considered this strategy during the entire lactation period in goats. Two experiments were performed using lactating Payoya goats. In experiment 1, to study the effect, over 180 days, of DOP on milk yield and composition, blood metabolites and economic values, 44 primiparous goats were allocated into three groups: control diet (concentrate plus lucerne) and DOP40 and DOP80 diets, in which DOP replaced 40% and 80%, respectively, of the cereals. Nutrient digestibility and rumen fermentation were also studied (experiment 2). The DOP diets did not affect milk yield and composition. DOP triggered lower intake and digestibility of ether extract and crude protein. Ruminal fermentation was unaffected by DOP, except for a decrease in butyrate for DOP80. The energy balance was unaltered by diet while the balance and retention of nitrogen decreased. Regarding plasma biochemistry, DOP supplementation caused changes that could indicate an improvement in hepatic function and reduced muscular damage and oxidative muscular stress. Moreover, DOP80 provided a profit increase of EUR 3.27/goat. In conclusion, the partial replacement of cereals by DOP is a profitable and healthy nutritional strategy in dairy goats and is suitable for the entire lactation period without compromising productivity.

Different Non-Structural Carbohydrates/Crude Proteins (NCS/CP) Ratios in Diet Shape the Gastrointestinal Microbiota of Water Buffalo

The microbiota of the gastrointestinal tract (GIT) are crucial for host health and production efficiency in ruminants. Its microbial composition can be influenced by several endogenous and exogenous factors. In the beef and dairy industry, the possibility to manipulate gut microbiota by diet and management can have important health and economic implications. The aims of this study were to characterize the different GIT site microbiota in water buffalo and evaluate the influence of diet on GIT microbiota in this animal species. We characterized and compared the microbiota of the rumen, large intestine and feces of water buffaloes fed two different diets with different non-structural carbohydrates/crude proteins (NSC/CP) ratios. Our results indicated that Bacteroidetes, Firmicutes and Proteobacteria were the most abundant phyla in all the GIT sites, with significant differences in microbiota composition between body sites both within and between groups. This result was particularly evident in the large intestine, where beta diversity analysis displayed clear clustering of samples depending on the diet. Moreover, we found a difference in diet digestibility linked to microbiota modification at the GIT level conditioned by NSC/CP levels. Diet strongly influences GIT microbiota and can therefore modulate specific GIT microorganisms able to affect the health status and performance efficiency of adult animals.

Effect of Potato By-Product on Production Responses of Dairy Cows and Total Mixed Ration Stability

Vegetable by-products have great potential for use as animal feeds and thus could improve the sustainability of the food system. The objective was to evaluate the milk production potential of potato by-product (PBP) replacing cereal grains in grass silage-based total mixed ration (TMR). Additionally, a laboratory scale experiment was conducted to assess the effect of PBP and chemical preservatives on the aerobic stability of TMRs. A change-over dairy cow feeding experiment was conducted to evaluate the inclusion of 135 g/kg (on a dry matter (DM) basis) of PBP in TMR. Additionally, the aerobic stability of TMR was evaluated by preparing TMRs with increasing levels of PBP and treated with different doses of formic and propionic acid or salt-based preservatives. The inclusion of PBP in dairy cow diets decreased feed intake, but organic matter digestibility was greater in the PBP diet, resulting in only slightly decreased production (milk protein 1435 vs. 1363 g/day, p < 0.05; milk lactose 1716 vs. 1606 g/day, p < 0.05). The aerobic stability of TMR was negatively affected by the inclusion of PBP, but it could to a limited extent be prolonged using chemical preservatives. The inclusion of PBP decreased feed intake and milk production to some extent when included in the diet of high-producing dairy cows. The utilization of PBP may, however, be justified from a sustainability point of view, as it provides a way to circulate the nutrients of a non-human edible feed material back into the food chain.

Olive Tree in Circular Economy as a Source of Secondary Metabolites Active for Human and Animal Health Beyond Oxidative Stress and Inflammation

Extra-virgin olive oil (EVOO) contains many bioactive compounds with multiple biological activities that make it one of the most important functional foods. Both the constituents of the lipid fraction and that of the unsaponifiable fraction show a clear action in reducing oxidative stress by acting on various body components, at concentrations established by the European Food Safety Authority's claims. In addition to the main product obtained by the mechanical pressing of the fruit, i.e., the EVOO, the residual by-products of the process also contain significant amounts of antioxidant molecules, thus potentially making the Olea europea L. an excellent example of the circular economy. In fact, the olive mill wastewaters, the leaves, the pomace, and the pits discharged from the EVOO production process are partially recycled in the nutraceutical and cosmeceutical fields also because of their antioxidant effect. This work presents an overview of the biological activities of these by-products, as shown by in vitro and in vivo assays, and also from clinical trials, as well as their main formulations currently available on the market.

Application of Olive By-Products in Livestock with Emphasis on Small Ruminants: Implications on Rumen Function, Growth Performance, Milk and Meat Quality

The olive oil industry has a leading position in the Mediterranean countries, resulting in the production of considerable quantities of the respective by-products (OB) that constitute an important environmental issue. OB contain valuable nutrients and bioactive components that can be re-used under the bioeconomy strategy, and several chemical, physical, and biological processes have been evaluated with the intention to improve their nutritional value. One feasible application of OB is their incorporation in the diets of livestock and especially ruminants due to their high fiber content. As indicated by numerous studies, OB dietary supplementation increases the levels of monounsaturated fatty acids (MUFAs) and decreases that of saturated fatty acids (SFAs) in the milk and meat of ruminants with beneficial effects for consumers' health. At the same time, environmental impact and feeding costs are reduced without detrimental effects on ruminal fermentation, nutrients utilization, growth performance, carcass traits, milk yield and composition.

Towards sustainable management of tomato pomace through the recovery of valuable compounds and sequential production of low-cost biosorbent

The present study focused on the full valorization of the tomato by-product, also known as tomato pomace consisting mainly of tomato peels and tomato seeds, by recovering natural antioxidants and edible oil, and subsequently reutilizing the leftover solid residues for the production of low-cost biosorbent. The tomato peel extract recovered using ethanol as food-grade solvent contained high phenol and flavonoid contents (199.35 ± 0.35-mg gallic acid equivalents (GAE)/g and 102.10 ± 0.03-mg quercetin equivalent (QE)/g, respectively). Even its lower content of lycopene (3.67 ± 0.04 mg/100 g), tomato peel extract showed potent antioxidant activity and can be therefore used as natural antioxidants either for food or cosmetic applications. High nutritional quality edible oil (17.15%) was extracted from tomato seeds and showed richness in unsaturated fatty acids (74.62%), with linoleic acid being the most abundant polyunsaturated fatty acid (49.70%). After recovery of these valuable compounds, the extraction solid leftovers were used to produce low-cost biosorbent tested for dye removal. Results showed that the highest biosorption yields were increasingly attributed to the acidic, direct, anthraquinone, then reactive dyes. Overall, the obtained results strongly support the complete utilization of tomato pomace for the recovery of valuable compounds and the sequential production of low-cost biosorbent.

Effect of Parity on Reproductive Performance and Composition of Sow Colostrum during First 24 h Postpartum

The aim of this study is to assess the effects of parity number on sow reproductive performance and the chemical and immunological composition of colostrum and immunoglobin concentrations in the sera of the sows. Colostrum samples were collected at 0, 6 and 24 h after the births of the first piglets from 56 sows with different numbers of parturitions (ranging 1-6). The piglets born alive to primiparous sows had lower birth weights (p < 0.05) than piglets from second and fourth parturition sows. The colostrum composition was influenced (p < 0.05) by parity number: primiparous sows had higher concentrations of dry matter, fat, lactose and non-fat-solids. No parity-dependent differences were found concerning total protein amount. Colostrum composition was drastically affected (p < 0.001) by sampling time-the highest concentrations of dry matter and protein and lowest concentrations of fat and lactose were found immediately after parturition (0 h). The study revealed no effect of parity (p ≥ 0.05) on the concentrations of immunoglobulins in colostrum. The immunoglobulin with the highest level in sow serum at day 110 of gestation was IgG, while IgA showed the lowest values and greater variability with respect to parity from an immunological point of view. Regarding the relationship between serum Ig levels at the end of gestation and colostrum Ig, serum IgG showed a strong correlation with colostrum IgG and IgM, while colostrum IgG was strongly related with colostrum IgM, but not with IgA. IgA did not correlate with any other immunoglobulin. The different behaviors of the immunoglobins in colostrum were probably due to IgG coming almost exclusively from the sows' sera, whereas IgA is mainly synthetized by the mammary gland.

Long-Term Feeding of Dairy Goats with Broccoli By-Product and Artichoke Plant Silages: Milk Yield, Quality and Composition

The aim of this experiment was to study the effects of a 40% inclusion of broccoli by-product (BB) and artichoke plant (AP) silages in dairy goat diets on the milk yield, composition and animal health status during a full lactation. Feed consumption was lower in AP and BB animals due to their composition and higher moisture content, and BB animals showed a significant reduction in body weight. Milk from the BB treatment had the highest fat content, total solids and useful dry matter content (5.02, 13.9 and 8.39%, respectively). The Se level was slightly lower in AP and BB animals; however, the milk of these treatments was the lowest in Na and, in the case of BB animals, the richest in Ca (1267 mg/kg). Control and AP milk showed a similar fatty acid profile, although AP had a more beneficial aptitude for human health (lower ratio of n6/n3, 12.5). Plasma components, as metabolic parameters, were adequate for goats. It was concluded that a 40% inclusion of AP is an adequate solution to reduce the cost of feeding without harming the animals' health or performance and to improve the nutritional milk quality. It is necessary to lower the BB level of inclusion to increase feed consumption.

Effect of the Use of Tomato Pomace on Feeding and Performance of Lactating Goats

Simple Summary

Inclusion of agro-industrial wastes reduces animal feed costs. However, it is very important to assess the effect this can have on the health and physiological condition of animals, as well as on the production and quality of milk. Therefore, this study was proposed with the objective of evaluating these aspects and verifying the optimal dose to maximize the farmers’ economic margin without affecting animals or their production. Inclusion of 40% tomato pomace does not influence the physiological characteristics of animals, and in turn improves both milk production and composition. Therefore, it can be concluded that formulation of the goats’ diet including 40% tomato pomace is the best option for animal diet.

Abstract

The aim of this research was to evaluate the effect of including different levels of tomato pomace (TP) on performance, blood biochemical parameters, hormones, production and composition of milk, and economic analysis of Saanen goats reared in confinement. Sixteen multiparous goats (Saanen), 21 days in milk, were randomly distributed in two Latin square 4 × 4 (four periods and four treatments), according to the inclusion levels of dehydrated tomato pomace (0%, 20%, 40%, and 60%) in the diet. This inclusion resulted in differences in the intake of dry and organic matter, as well as ether extract, crude protein, water, neutral detergent fiber, and non-fibrous carbohydrates. The inclusion of 60% TP resulted in a significant decrease of body weight (−4.42 kg) in comparison with initial body weight, while the other three treatments did not affect or increase the animal body weight (between −0.05 and +3.07 kg). The addition of 20% and 40% of TP resulted in higher milk production (around 1.5 kg day⁻¹) than in animals from a control (1.2 kg day⁻¹) and 60% TP (1.04 kg day⁻¹). This increase was approximately 28% in the animals with 40% of TP inclusion. Moreover, the addition of 20% or 40% TP also improved the milk quality, which presented a higher fat amount (4.37% and 4.63% in 20% TP and 40% TP animals, respectively) than in a control (3.7%) and animals feed with 60% TP (4.02%). The feed efficiency and feed conversion did not show differences between diets. Thyroid hormones (T3 and T4) were also significantly affected by the inclusion of TP in the diet. The diet with the highest level of TP (60%) had the lowest cost per kilo among the diets evaluated. However, the use of 40% TP in animal diet presented the highest milk production and intermediate production cost.

The use of ensiled olive cake in the diets of Friesian cows increases beneficial fatty acids in milk and Halloumi cheese and alters the expression of SREBF1 in adipose tissue

This study aimed to evaluate the effect of dietary inclusion of ensiled olive cake, a by-product of olive oil production, on milk yield and composition and on fatty acid (FA) profile of milk and Halloumi cheese from cows. Furthermore, the effect of olive cake on the expression of selected genes involved in mammary and adipose lipid metabolism was assessed in a subset of animals. A total of 24 dairy cows in mid lactation were allocated into 2 isonitrogenous and isoenergetic feeding treatments, named the control (CON) diet and the olive cake (OC) diet, in which part of the forages (alfalfa, barley hay, and barley straw) were replaced with ensiled OC as 10% of dry matter according to a 2 × 2 crossover design with two 28-d experimental periods. At the end of the second experimental period, mammary and perirenal adipose tissue samples were collected from 3 animals per group for gene expression analysis by quantitative reverse-transcription PCR. The expression of 11 genes, involved in FA synthesis (ACACA, FASN, G6PDH), FA uptake or translocation (VLDLR, LPL, SLC2A1, CD36, FABP3), FA saturation (SCD1), and transcriptional regulation (SREBF1, PPARG), was evaluated. No significant differences were observed between groups concerning milk yield, fat percentage, protein percentage, and protein yield (kg/d), whereas milk fat yield (kg/d) increased in the OC group. Dietary supplementation with ensiled OC modified the FA profile of milk and Halloumi cheese produced. There was a significant decrease in the concentration of de novo synthesized FA, saturated FA, and the atherogenic index, whereas long-chain and monounsaturated FA concentration was increased in both milk and cheese. Among individual saturated FA, only stearic acid was elevated, whereas among individual monounsaturated FA, increments of oleic acid (C18:1 cis-9) and the sum of C18:1 trans-10 and trans-11 acids were demonstrated in milk and Halloumi cheese produced. Although no diet effect was reported on total polyunsaturated FA, the concentration of CLA cis-9,trans-11 was increased in both milk and Halloumi cheese fat of the OC group. The expression of the genes tested was unaffected apart from an observed upregulation of SREBF1 mRNA expression in perirenal fat from cows fed the OC diet. Milk FA differences observed were not associated with alterations in mammary expression of genes involved in FA synthesis, uptake, translocation, and regulation of lipogenesis. Overall, the inclusion of ensiled OC in cow diets for a 4-wk period improved, beneficially for human health, the lipid profile of bovine milk and Halloumi cheese produced without adversely affecting milk yield and composition or the expression of genes involved in lipid metabolism of mammary and adipose tissues in cows.

Characterization and management strategies for process discharge streams in California industrial tomato processing

The California tomato industry is the leading processor of tomatoes in the world. Accordingly, it produces a large amount of solid and liquid byproducts during processing. Some of these byproducts are under-utilized and discarded. There is increasing demand for the conversion of tomato byproducts into value-added products. This study reviews the characteristics of solid residue and process water discharge streams generated at different stages of tomato processing in addition to their current management strategies. Furthermore, relevant policy that governs management of solid and liquid organic byproducts for California tomato processors is discussed. Finally, recommendations for novel and sustainable management strategies are explored.

Inoculation with rumen fluid in early life as a strategy to optimize the weaning process in intensive dairy goat systems

Ruminants are born with an undeveloped physical, metabolic, and microbial rumen. Rumen development is limited under artificial rearing systems when newborn animals are separated from the dam, fed on milk replacer, and weaned at an early age. This study aims to evaluate the effects of early-life inoculation of young ruminants with rumen fluid from adult animals. Eighty newborn goat kids were randomly allocated to 1 of 4 experimental treatments and inoculated daily from d 1 to wk 11 with autoclaved rumen fluid (AUT), fresh rumen fluid obtained from adult goats fed either a forage diet (RFF) or concentrate-rich diet (RFC), or absence of inoculation (CTL). Goat kids were artificially reared with ad libitum access to milk replacer, starter concentrate, and forage hay. Blood was sampled weekly and rumen microbial fermentation was monitored at 5 (preweaning), 7 (weaning), and 9 wk of age (postweaning). Results indicated that inoculation with fresh rumen fluid accelerated the rumen microbial and fermentative development before weaning. As a result, RFC and RFF animals had higher solid feed intake (+73%), rumen concentrations of ammonia-N (+26%), total volatile fatty acids (+46%), butyrate (+50%), and plasma β-hydroxybutyrate (+48%), and lower milk intake (-6%) than CTL and AUT animals at wk 5. Inoculation with fresh inoculum also promoted early rumen colonization by a complex and abundant protozoal community, whereas CTL animals remained protozoa free. Although all kids experienced moderate growth retardation during 1 wk after weaning, inoculation with fresh rumen fluid favored the weaning process, leading to 2.2 times higher weight gain than CTL and AUT animals during wk 8. Some of these advantages were retained during the postweaning period and RFF and RFC animals showed higher forage intake (up to +44%) than CTL and AUT animals with no detrimental effects on feed digestibility or stress levels. The superior microbial load of RFC compared with RFF inoculum tended to provide further improvements in terms of forage intake, plasma β-hydroxybutyrate, and rumen protozoa, whereas AUT inoculation provided minor (if any) advantages with respect to CTL animals. Although no differences were noted on animal growth, this study suggests that early life inoculation of goat kids with rumen microbiota can represent an effective strategy to accelerate the rumen development, facilitating a smooth transition from milk to solid feed and to the potential implementation of early weaning strategies.

Short-Term Effect of the Inclusion of Silage Artichoke By-Products in Diets of Dairy Goats on Milk Quality

Simple Summary

The use of artichoke by-products, both from the canning industry or from the stubble that remains in the field, provides a cheaper source of nutrients, suitable for ruminant feeding due to their ability to digest fibre-rich foods. The use of these by-products for animal feed is also a way to reduce waste caused by the canning industry and disposal costs, as well as the area and resources allocated to the production of food for livestock, contributing to the circular economy. Evaluating the effect of the inclusion of silage artichoke by-products (bracts and rest of crop plant) in dairy goat rations on the milk yield and composition, animal health status, mineral and lipid profile is an effective way to explore the suitability of these alternative feedstuffs for goat cattle. The use of artichoke bracts and whole plant silage in dairy goat diets does not lead to marked differences in the milk yield and quality or the animals’ health status. From a nutritional point of view for human health, slightly better mineral and lipid profiles are observed in milk from goats fed artichoke plant silage, due to its higher polyunsaturated fatty acids and conjugated linoleic acid contents.

Abstract

Artichoke by-products represent a high amount of waste whose removal entails several costs. Moreover, feed is the main cost in a farm. So, including these by-products in ruminant diets would lower feed costs. Two experiments were conducted to evaluate the effect of two levels of inclusion, 12.5% and 25.0%, of two silages of artichoke by-products (artichoke bracts, AB and artichoke plant, AP) in the diet of goats on the milk yield, composition and quality and on the metabolic profile of the animals. AB presented the lowest blood urea content and there were no differences in milk yield in the two experiments. However, with 25.0% of silage by-product in the diet, a higher fat content was observed in AB and of protein in AP, as well as this treatment showing a slightly higher Se content. Regarding the milk lipid profile, milk from 12.5% of AP treatment presented a higher PUFA content. In conclusion, the use of silage artichoke by-products in dairy goat diets does not jeopardise milk yield and quality and health status of animals and, from a nutritional point of view for human health, a slightly better mineral and lipid profile is observed in milk from AP treatments.

Can Agro-Industrial By-Products Rich in Polyphenols be Advantageously Used in the Feeding and Nutrition of Dairy Small Ruminants?

Simple Summary

In the Mediterranean area, where dairy sheep and goats are widespread, the use of by-products in the diet of small ruminants is an ancient practice. Today the great availability of industrial by-products produced at the local level (e.g., grape, olive, tomato and myrtle residues), appears to be a promising strategy for reducing competition with human edible foods and the cost of off-farm produced feeds since they are imported worldwide. Moreover, these co-feeds can contribute to reducing the ecological and water footprint associated with crop cultivation. The presence of bioactive compounds, such as polyphenols, confers added value to these materials. Several positive aspects are apparent when such by-products are included in the diets of small dairy ruminants, in particular on ruminal metabolism, animal health, and the quality of derived products.

Abstract

Recently, the interest in industrial by-products produced at the local level in Mediterranean areas, resulting from fruit and vegetable processes, has increased because of their considerable amounts of bioactive compounds, including polyphenols. In this review, we analyze the most recent scientific results concerning the use of agro-industrial by-products, naturally rich in polyphenols (BPRP), in the diets of small dairy ruminants. Effects on milk production, milk and rumen liquor fatty acid profile, metabolic parameters, and methane production are reviewed. The feed intake and digestibility coefficients were generally depressed by BPRP, even though they were not always reflected in the milk yield. The main observed positive effects of BPRP were on quality of the milk’s FA profile, antioxidant activity in milk and blood, a reduction of rumen ammonia, and, consequently, a reduction of milk and blood urea. The expected beneficial effects of dietary polyphenols in small ruminants were not always observed because of their complex and variable matrices. However, owing to the large quantities of these products available at low prices, the use of BPRB in small ruminant nutrition offers a convenient solution to the valorization of residues arising from agricultural activities, reducing feed costs for farmers and conferring added value to dairy products at the local level, in a sustainable way.

Climate Change Impact, Adaptation, and Mitigation in Temperate Grazing Systems: A Review

Managed temperate grasslands occupy 25% of the world, which is 70% of global agricultural land. These lands are an important source of food for the global population. This review paper examines the impacts of climate change on managed temperate grasslands and grassland-based livestock and effectiveness of adaptation and mitigation options and their interactions. The paper clarifies that moderately elevated atmospheric CO2 (eCO2) enhances photosynthesis, however it may be restiricted by variations in rainfall and temperature, shifts in plant’s growing seasons, and nutrient availability. Different responses of plant functional types and their photosynthetic pathways to the combined effects of climatic change may result in compositional changes in plant communities, while more research is required to clarify the specific responses. We have also considered how other interacting factors, such as a progressive nitrogen limitation (PNL) of soils under eCO2, may affect interactions of the animal and the environment and the associated production. In addition to observed and modelled declines in grasslands productivity, changes in forage quality are expected. The health and productivity of grassland-based livestock are expected to decline through direct and indirect effects from climate change. Livestock enterprises are also significant cause of increased global greenhouse gas (GHG) emissions (about 14.5%), so climate risk-management is partly to develop and apply effective mitigation measures. Overall, our finding indicates complex impact that will vary by region, with more negative than positive impacts. This means that both wins and losses for grassland managers can be expected in different circumstances, thus the analysis of climate change impact required with potential adaptations and mitigation strategies to be developed at local and regional levels.

Recent insight and future techniques to enhance rumen fermentation in dairy goats

Recent development of novel techniques in systems biology have been used to improve and manipulate the rumen microbial ecosystem and gain a deeper understanding of its physiological and microbiological interactions and relationships. This provided a deeper insight and understanding of the relationship and interactions between the rumen microbiome and the host animal. New high-throughput techniques have revealed that the dominance of Proteobacteria in the neonatal gut might be derived from the maternal placenta through fetal swallowing of amniotic fluid in utero, which gradually decreases in the reticulum, omasum, and abomasum with increasing age after birth. Multi "omics" technologies have also enhanced rumen fermentation and production efficiency of dairy goats using dietary interventions through greater knowledge of the links between nutrition, metabolism, and the rumen microbiome and their effect in the environment. For example, supplementation of dietary lipid, such as linseed, affects rumen fermentation by favoring the accumulation of α-linolenic acid biohydrogenation with a high correlation to the relative abundance of Fibrobacteriaceae. This provides greater resolution of the interlinkages among nutritional strategies, rumen microbes, and metabolism of the host animal that can set the foundation for new advancements in ruminant nutrition using multi 'omics' technologies.

Recent advances in the feeding and nutrition of dairy goats

There have been recent advances concerning research of the feeding and nutrition of dairy goats in a wide array of areas. Ruminally emitted methane and supplementary feedstuffs to a lesser extent make appreciable contributions to the carbon footprint of dairy goats, with the former affected by type of production system and associated dietary characteristics. Unique behavior of goats necessitates careful consideration of the nature of confinement facilities to achieve optimal production by animals differing in social hierarchy. Physiological conditions such as nutritional needs and perhaps health status may influence diet selection by goats in both grazing and confinement settings. Some research suggests that low concentrations of protein and fat in milk of high-yielding dairy goat breeds could involve the type and nature of dietary ingredients as influencing end products of ruminal fermentation. With the relationship between milk urea nitrogen concentration and efficiency of dietary protein utilization, through future research the measure may be a useful tool for diet formulation as in dairy cattle. Effects of dietary inclusion of sources of fats and oils vary considerably depending on their nature, as is also true for byproduct feedstuffs and conventional ones being substituted for. Supplementation of dairy goats with sources of polyunsaturated fatty acids can affect oxidative stress and various feedstuffs influence antioxidant status; however, research addressing the significance of such changes under practical production settings would be beneficial.

Nutritive Value of Tomato Pomace for Ruminants and Its Influence on In Vitro Methane Production

Simple Summary

Reutilization of agroindustrial by-products in animal feeding could contribute to the reduction of environmental problems associated with their accumulation, but it is necessary to assess their nutritive value. Tomato pomace (TP) is a by-product of the tomato industry that could be used in ruminant feeding, but data on its nutritive value are limited. The aim of this work was to analyze the chemical composition, in vitro rumen fermentation, and intestinal digestibility of 12 TP samples obtained from two processing plants at different times during the tomato campaign and to assess the in vitro fermentation of diets including increased TP amounts. The chemical composition of TP showed little variability. Samples of TP had high fiber, protein, and fat content and were rapidly fermented in the rumen, but the in vitro intestinal digestibility of the protein was low. The in vitro results provide useful information for including TP in ruminant diets, indicating that amounts of TP up to 180 g/kg could be included in a diet for fattening ruminants without negatively affecting rumen fermentation, but these results should be confirmed in vivo.

Abstract

The objective of this study was to determine the variability in nutritive value for ruminants of tomato pomace (TP) samples and analyze its effect on in vitro fermentation when it was included in a high-concentrate diet. Twelve TP samples were obtained from two processing plants at weekly intervals and analyzed for chemical composition, in vitro rumen fermentation, and intestinal digestibility. The chemical composition of TP did not differ between processing plants and only slight variations were observed among sampling times. Tomato pomace had a low dry matter content (<300 g/kg), a high content of neutral detergent fiber, crude protein, and ether extract (572, 160, and 82.7 g/kg dry matter on average, respectively), and was rapidly fermented in the rumen. Protein degradability at 16 h in situ incubation was 510 g/kg and in vitro intestinal digestibility of protein was low (430–475 g/kg). Replacing soybean meal and barley straw by dried TP increased the in vitro fermentation rate and the production of volatile fatty acids and reduced NH₃-N concentrations without affecting CH₄. In summary, TP samples showed little variability in nutritive value over sampling time and TP of up to 180 g/kg could be included in high-concentrate diets without negatively affecting rumen fermentation.

In vitro assessment of the factors that determine the activity of the rumen microbiota for further applications as inoculum

BACKGROUND

The rumen microbiota has been used as inoculum for in vitro studies and as a probiotic to improve productivity in young animals. However, great variability across studies has been noted depending on the inoculum considered. The present study aims to assess the relevance of different factors (microbial fraction, collection time, donor animal diet, fermentation substrate and inoculum preservation method) to maximize the rumen inoculum activity and set the standards for further in vitro and in vivo applications.

RESULTS

Rumen inoculum sampled at 3 h after feeding led to greater microbial growth and activity [+12% volatile fatty acid (VFA), +17% ammonia] compared to before feeding. Similar results were noted when rumen liquid or rumen content were used as inocula. Rumen inoculum adapted to concentrate diets increased microbial activity (+19% VFA) independently of the substrate used in vitro. Freezing-thawing the inoculum, in comparison to fresh inoculum, decreased microbial activity (-14% VFA, -96% ammonia), anaerobic fungi and protozoa, with holotrichs protozoa being particularly vulnerable. Inoculum lyophilization had a stronger negative effect on microbial activity (-51% VFA) and delayed re-activation of the microbes, leading to lower levels of methanogens and anaerobic fungi, as well as almost complete wipe out of rumen protozoa.

CONCLUSIONS

Fresh rumen fluid sampled at 3 h after feeding from donor animals that were fed concentrate diets should be chosen when the aim is to provide the most diverse and active rumen microbial inoculum. © 2018 Society of Chemical Industry.

Review: Alternative and novel feeds for ruminants: nutritive value, product quality and environmental aspects

Ruminant-based food production faces currently multiple challenges such as environmental emissions, climate change and accelerating food-feed-fuel competition for arable land. Therefore, more sustainable feed production is needed together with the exploitation of novel resources. In addition to numerous food industry (milling, sugar, starch, alcohol or plant oil) side streams already in use, new ones such as vegetable and fruit residues are explored, but their conservation is challenging and production often seasonal. In the temperate zones, lipid-rich camelina (Camelina sativa) expeller as an example of oilseed by-products has potential to enrich ruminant milk and meat fat with bioactive trans-11 18:1 and cis-9,trans-11 18:2 fatty acids and mitigate methane emissions. Regardless of the lower methionine content of alternative grain legume protein relative to soya bean meal (Glycine max), the lactation performance or the growth of ruminants fed faba beans (Vicia faba), peas (Pisum sativum) and lupins (Lupinus sp.) are comparable. Wood is the most abundant carbohydrate worldwide, but agroforestry approaches in ruminant nutrition are not common in the temperate areas. Untreated wood is poorly utilised by ruminants because of linkages between cellulose and lignin, but the utilisability can be improved by various processing methods. In the tropics, the leaves of fodder trees and shrubs (e.g. cassava (Manihot esculenta), Leucaena sp., Flemingia sp.) are good protein supplements for ruminants. A food-feed production system integrates the leaves and the by-products of on-farm food production to grass production in ruminant feeding. It can improve animal performance sustainably at smallholder farms. For larger-scale animal production, detoxified jatropha (Jatropha sp.) meal is a noteworthy alternative protein source. Globally, the advantages of single-cell protein (bacteria, yeast, fungi, microalgae) and aquatic biomass (seaweed, duckweed) over land crops are the independence of production from arable land and weather. The chemical composition of these feeds varies widely depending on the species and growth conditions. Microalgae have shown good potential both as lipid (e.g. Schizochytrium sp.) and protein supplements (e.g. Spirulina platensis) for ruminants. To conclude, various novel or underexploited feeds have potential to replace or supplement the traditional crops in ruminant rations. In the short-term, N-fixing grain legumes, oilseeds such as camelina and increased use of food and/or fuel industry by-products have the greatest potential to replace or supplement the traditional crops especially in the temperate zones. In the long-term, microalgae and duckweed of high-yield potential as well as wood industry by-products may become economically competitive feed options worldwide.

Milk Technological Properties as Affected by Including Artichoke By-Products Silages in the Diet of Dairy Goats

Traditional farming practices include the use of local agricultural by-products in the diet of ruminants. Artichoke harvesting and transformation yield high amounts of by-products that, if properly used, may reduce farming costs and the environmental impact of farming. The present study tests the inclusion of silages from artichoke by-products (plant and outer bracts) in the diet of dairy goats (0%, 12.5% and 25% inclusion) on the technological and sensory properties of milk during a five-month study. Milk composition, color, stability, coagulation and fermentation properties remained unaffected by diet changes. Panelists were not able to differentiate among yogurts obtained from those milks by discriminant triangular sensory tests. Silages of artichoke by-products can be included in isoproteic and isoenergetic diets for dairy goats, up to a 25% (feed dry matter), without negatively affecting milk technological and sensory properties whereas reducing feeding costs.