This was a field protocol and observational mapping study rather than an experiment measuring the ecological effects of grazing. Its authors focused on an area encompassing two corridors in central Italy: Corridor 1 links the Sirente-Velino Regional Natural Park with the Abruzzo, Lazio and Molise National Park, while Corridor 2 connects the latter with the Majella National Park. The corridors support Marsican bears and also provide habitat for mammals including roe deer, red deer, wild boar and porcupine.

To compile the data, the researchers requested 2023 livestock records from municipal offices in the 15 municipalities wholly or partly within the study area. The records included the number of animals assigned to farms using municipal pasture under Italy’s annual or seasonal “fida pascolo” grazing-concession system. This system is governed by provisions dating from 1927 and 1928, while the cadastral framework for land parcels derives from an 1886 law. Municipal documents identified the relevant cadastral sheets and parcels and the livestock numbers associated with each farm, although completeness and detail varied among municipalities.

Farmers were interviewed anonymously to fill gaps in animal-category classifications and records of where pastures were located. On-site visits supplied pasture assignments by cadastral sheet and animal numbers by species and age class. The resulting database recorded the municipality, an anonymised farm code, cadastral sheet, area allocated in hectares, and numbers of cattle older than 24 months, cattle aged 6–24 months, cattle younger than six months, sheep and goats older than 12 months, and horses older than six months. Only aggregate information was published to protect farms’ identities and locations.

For mapping, the team selected cadastral sheets from the Italian national cadastral cartography and combined them with livestock data in QGIS. Where animal numbers were available by farm and parcel, the parcels’ areas were proportionally allocated to the relevant cadastral sheet, under an assumption that animals were distributed evenly within it. For Gagliano Aterno, where the records identified grazed sheets but not animal numbers for each one, the calculation used the municipality’s total livestock divided by its total grazed area. The protocol then associated livestock counts and densities with the mapped sheets.

Grazing pressure was expressed in livestock units, or LSUs, to combine different animal categories. Under European Commission Implementing Regulation 2016/669 conversion factors used by the municipalities, cattle and equines over the specified age thresholds counted as 1 LSU, cattle aged six months to two years as 0.6 LSU, cattle below six months as 0.4 LSU, and sheep and goats as 0.15 LSU. The resulting shapefile contained eight mapped variables: LSU, LSU density, equines, equines density, cattle, cattle density, sheep and goats combined, and their density.

Gagliano Aterno had the highest municipal LSU count, at 461.8, followed by Ortona dei Marsi with 373.2, Anversa degli Abruzzi with 350.7 and Scanno with 295.2. Gagliano Aterno also recorded the most cattle, with 366, compared with 204 in Ortona dei Marsi and 166 in Cocullo. Cattle density was highest in Ortona dei Marsi at 2.03 cattle per hectare of grazed cadastral sheets, followed by Scanno at 0.96. Anversa degli Abruzzi had the largest combined sheep-and-goat count, 1,173 animals, and the highest density, 8.21 individuals per hectare; Scanno ranked third in that category’s density at 5.38. Ortona dei Marsi had both the largest equine population, 117, and the highest equine density, 1.62 per hectare.

The municipal LSU estimates were generally higher than values from two larger-scale studies by Malek and colleagues, although some municipalities showed higher comparison values in one of those datasets. After horses were excluded because the comparison datasets omitted them, the protocol’s municipal values showed a moderate correlation with Malek et al. (2024a), although the result was not statistically significant at the 0.05 threshold (Spearman’s rho 0.47, p=0.08). Correlation with Malek et al. (2024b) was weak (Spearman’s rho 0.14, p=0.02). The authors attributed differences to methodological variation and the use of different LSU coefficients.

Several limitations constrain the maps. They exclude livestock on private pastureland because those data were unavailable, which may cause some underestimation even though private grazing was a small part of the mapped region. The method assigns livestock to cadastral sheets rather than locating individual animals, and its homogeneous-distribution assumption may not reflect unequal forage availability or herds concentrating in particular places. Results also have limited temporal validity because municipal grazing concessions are renewed annually and may change each year. The protocol nevertheless identifies mapped areas for assessing potential overgrazing and the interactions between pasture activity, habitat conditions, wildlife and possible pathogen transmission in bear corridors.

Subject of Research: Standardised mapping of livestock grazing pressure in two Central Apennines ecological corridors

Article Title: Map of livestock density in Central Appenines: a standardised protocol

Article References: Dragonetti, C., Masiello, G., Villa, F., Von Kempis, S. R., Cipollone, M., & Di Marco, M. (2025). Map of livestock density in Central Appenines: a standardised protocol. Nature Conservation, 59, 335-349. https://doi.org/10.3897/natureconservation.59.155735

Image Credits: AI Generated

DOI: 10.3897/natureconservation.59.155735

Keywords: livestock density, grazing pressure, Central Apennines, Marsican brown bear, municipal pastures, livestock units, GIS mapping, biodiversity conservation, livestock, density, Central, Appenines

The premise is deceptively simple. Goats are evolutionary intermediates between browsers and grazers, and studies show they can satisfy up to 60 percent of their nutritional needs from foliage when given the choice. Yet European husbandry guidelines recommend pasture access without requiring access to trees and shrubs. Fast-growing poplars and willows, cultivated widely in alley-cropping and short-rotation plantations across temperate latitudes, already serve as feed for sheep and cattle in New Zealand, China, North America, and parts of Europe. In Germany alone, roughly 6,600 hectares of short-rotation poplar and willow plantations yield about nine tonnes of woody dry mass per hectare annually, along with up to three tonnes of foliage per hectare in the second year after planting. Whether that foliage actually delivers usable nutrition to goats, however, had never been thoroughly tested.

The researchers ran two linked experiments. In the first, four castrated Saanen goat wethers, each about 1.5 years old, were rotated through four diets in a 4-by-4 Latin square design: meadow hay alone, or hay supplemented with 650 grams per day of dried foliage from one of three hybrids, black poplar (Populus nigra × deltoides), balsam poplar (P. nigra × maximowiczii), or willow (Salix triandra × viminalis). During the third week of each feeding block, the animals were moved into respiration chambers where oxygen consumption, carbon dioxide production, and methane emissions were measured at six-minute intervals, while feces and urine were collected for complete nutrient, energy, and mineral balance calculations.

The chemical analysis alone was enough to turn heads. Compared with hay, the tree leaves contained up to ten times higher concentrations of crude protein, minerals, phenols, and measurable antioxidant capacity. Black poplar leaves were particularly rich in calcium at 21.6 grams per kilogram of dry matter, roughly five times the hay content, along with markedly higher zinc, copper, iron, magnesium, and selenium. Willow leaves carried the highest manganese levels and, remarkably, showed antioxidant capacity six to ten times greater than hay in standard ABTS and FRAP assays. The foliage also packed condensed tannins and phenolic compounds at two to three times the hay concentrations, a double-edged property that would prove consequential later in the study.

Digestibility results favored the poplars. Balsam poplar diets achieved the highest organic matter digestibility at 64 percent, compared with 59 percent for hay and just 56.1 percent for willow. Willow fared worst across the board, posting the lowest crude protein digestibility at 52.9 percent and the lowest fiber digestibility, a deficit the researchers attribute to its extraordinary condensed tannin content of 116.6 grams per kilogram of dry matter, some 22-fold higher than the poplar leaves. Tannins bind proteins and nutrients in the rumen, forming complexes that resist digestion and inflate fecal nitrogen losses. Despite this, microbial protein production in the rumen, estimated from urinary purine derivatives, was unaffected by any of the foliage diets.

Perhaps the most climate-relevant finding was what came out of the animals as gas. Methane emitted per kilogram of dry matter intake was significantly lower on all three foliage diets than on hay, with willow delivering the largest reduction at 17.2 grams per kilogram versus 22.4 for hay. Tannins suppress methanogenic archaea in the rumen, and the bacteriostatic effect appears to translate directly into reduced enteric methane, the potent greenhouse gas that accounts for a substantial share of livestock agriculture’s climate footprint. Notably, foliage feeding raised no red flags for food safety: despite leaves accumulating more zinc, manganese, nickel, and lead than hay, plasma concentrations of these heavy metals in the goats remained indistinguishable from hay-fed controls.

Selenium told a subtler story. Although balsam poplar leaves contained the most selenium, wethers fed the black poplar diet showed the highest plasma selenium at 72.6 micrograms per liter, significantly above both the balsam poplar and hay groups. Because selenium intake differed only marginally between the two poplar diets, the authors conclude that selenium from black poplar is more bioavailable, possibly reflecting differences between inorganic and organic selenium species in the leaves. This bioavailability advantage carried into the second experiment, where lactating does supplemented with black poplar foliage consumed 2.7 times more selenium and maintained significantly higher plasma selenium concentrations by the fifth week of lactation, hinting that tree foliage could partly substitute inorganic selenium supplements derived from fossil sources.

That second experiment put the most promising candidate to a real-world test. Sixteen pregnant, year-old Saanen goats were split after lambing: half received 700 grams per day of black poplar foliage alongside hay and wheat during the first five weeks of lactation, while the control group received hay and wheat only. The hypothesis was logical, even elegant. The periparturient period imposes crushing energy and calcium demands for fetal growth, colostrum, and milk production, driving negative mineral balances, body fat mobilization, and oxidative stress. Poplar leaves are loaded with calcium, selenium, and polyphenolic antioxidants, precisely the profile that might buffer these stresses.

The results dismantled that hope. Poplar-supplemented does showed no improvement in glutathione peroxidase activity or any other antioxidant marker, despite the leaves’ impressive laboratory antioxidant capacity, suggesting the phenolic compounds were poorly absorbed in vivo. Worse, in the second week after lambing the poplar group exhibited significantly lower serum calcium concentrations and a lower ratio of osteocalcin to CTX, the molecular signatures of bone formation and resorption, indicating intensified bone mobilization. The likely culprit is tannin chemistry: condensed tannins are known to hinder intestinal calcium absorption, and calcium actually enhances the binding between tannins and proteins, compounding the interference. The poplar does were losing more calcium from skeleton despite consuming nearly two and a half times more dietary calcium than controls.

The study’s authors draw a cleanly practical conclusion. Black poplar foliage is a genuinely valuable feed for non-lactating goats, offering improved protein digestibility, selenium status, and reduced methane yield, but it should not be fed to goats in early lactation, when calcium homeostasis is already stretched to its limit. The team acknowledges limitations, including small animal numbers that limited statistical power for mineral balances and methane measurements, and the well-documented sensitivity of leaf composition to harvest time, leaf age, soil, and climate. Still, in an era when agriculture urgently seeks feed resources that cut emissions without competing for cropland, the image of a goat stripping leaves from a poplar row has gained real scientific weight, provided farmers know exactly when in the reproductive calendar to open the gate.

Subject of Research: Nutritional value of poplar and willow foliage in goat diets and its effects on digestibility, selenium status, methane emission, and calcium metabolism around lambing

Article Title: Nutrient and energy digestibility, mineral status and antioxidant defense in goat wethers and periparturient does supplemented with poplar and willow leaves

Article References: Helffenstein, K., Schwerdtfeger, J., Görs, S., Durkalec, M., Kowalczyk, J., Eggert, A., Wilkens, M. R., & Kuhla, B. (2026). Nutrient and energy digestibility, mineral status and antioxidant defense in goat wethers and periparturient does supplemented with poplar and willow leaves. Frontiers in Animal Science, 7, Article 1861647. https://doi.org/10.3389/fanim.2026.1861647

Image Credits: AI Generated

DOI: 10.3389/fanim.2026.1861647

Keywords: goats, poplar foliage, willow, agroforestry, selenium, methane emissions, tannins, calcium metabolism, antioxidants, animal nutrition, early lactation, digestibility

The stakes are enormous. Sub-Saharan Africa is home to an estimated 1.1 billion cattle, sheep, and goats, roughly 27 percent of the global population of these species. They convert grasses and other fiber-rich feeds into meat and milk that underpin food and nutritional security for millions of Africans, supply draft power and manure to smallholder farms, and account for up to 75 percent of household incomes in some rural areas. Demand for animal-source proteins is projected to rise by as much as 55 percent per person by 2050, and many governments in the region are betting on livestock to drive economic growth. Yet parasites quietly erode that potential. Previous estimates suggest livestock keepers lose on average one animal per cattle sold and one animal for every two sheep or goats sold, and gastrointestinal parasites remain a major pathological cause of low efficiency and high mortality. Because many of these parasites also infect humans, the burden extends beyond the farm gate into public health.

To build the evidence map, the researchers followed PRISMA guidelines, searching Web of Science and Google Scholar between April and July 2025 for studies published between 2015 and 2024 that reported fecal-based parasite prevalence in cattle, sheep, or goats. Google Scholar was deliberately included because research outputs from sub-Saharan Africa are under-represented in major bibliographic databases, and the platform indexes African Journals Online and other regional sources. The search retrieved 507 records, which were filtered down to 111 eligible studies, including two doctoral theses. Studies based on experimental infections, intervention trials, case reports, reviews, or modeling were excluded, as were those lacking clear sample sizes or prevalence figures. The team applied the Joanna Briggs Institute checklist to appraise risk of bias and used the Condition, Context, Population framework to define eligibility, focusing on non-apparently sick ruminants in sub-Saharan Africa examined through field-applicable coprological methods.

The statistical machinery behind the pooled estimate is technically demanding. Because individual studies reported positive cases and total sample sizes rather than treatment effects, the team used meta-analysis of proportions, the recommended approach for prevalence synthesis. Raw proportions were normalized with the Freeman-Tukey double-arcsine transformation to address skewness and stabilize variance, then pooled with random-effects models estimated by restricted maximum likelihood, using the meta and metafor packages in R. Heterogeneity was quantified with Cochran’s Q, I², and 95 percent prediction intervals. Sensitivity analyses included leave-one-out assessments, identification of influential studies via externally studentized residuals with a z-score cutoff of 2.0, and risk-of-bias stratification. The results proved robust: excluding influential studies shifted the combined estimate only from 59.1 to 58.9 percent, and restricting the analysis to low-risk studies yielded 55.8 percent, with fully overlapping confidence intervals across all scenarios.

The pooled figures reveal a consistent host-species pattern. Sheep carried the highest prevalence at 64.0 percent, goats followed closely at 63.3 percent, and cattle trailed at 48.2 percent. The overlapping confidence intervals for sheep and goats suggest their regional burdens are broadly similar, and the authors attribute the small-ruminant disadvantage to a web of behavioral, immunological, and physiological factors. Sheep and goats, particularly when forage is scarce, graze closer to the ground and consume shorter herbage, increasing contact with infective third-stage larvae concentrated near the herbage-soil interface. Differences in acquired immunity, body size, and nutritional status may further depress average fecal detection in cattle. The authors caution, however, that the synthesis cannot pin the species gap on any single mechanism because these variables were not consistently reported across the primary studies.

Geography mattered just as much. Prevalence peaked in West Africa at 74.9 percent and Central Africa at 74.0 percent, fell to 55.0 percent in East Africa, and dropped to 26.4 percent in Southern Africa. Wetter, more humid conditions in parts of West and Central Africa likely favor the development and survival of free-living parasite stages and increase pasture contamination, while drier Southern African systems may experience lower transmission pressure. Regional differences in veterinary service coverage and anthelmintic use may reinforce these climatic effects: irregular deworming and limited access to veterinary inputs in many smallholder systems in East and West Africa are associated with sustained high prevalence, whereas more structured parasite control programs in some Southern African commercial systems likely contribute to lower burdens. The authors stress these explanations remain plausible hypotheses rather than causal inferences, and that the region variable is confounded by production systems, host composition, diagnostic methods, and uneven country representation.

Sample source also shaped the picture. On-farm studies, comprising 86 studies and 50,480 animals, yielded a pooled prevalence of 52.6 percent, while 21 abattoir-based studies covering 5,996 animals produced 48.2 percent. The on-farm data confirm that fecal-detected parasitism is widespread in the animals from which meat, milk, and manure are derived, while the abattoir figures show that infected animals routinely enter slaughter channels. Abattoir populations are selected animals, which may differ from farm populations in age, sex, and health status, so the two evidence streams should be treated as complementary rather than interchangeable. The authors argue that abattoirs deserve closer attention as surveillance interfaces, since slaughter and carcass processing involve direct contact with intestinal contents, blood, offal, and fecal material, creating recognized points of zoonotic exposure.

The parasite taxa most frequently reported tell their own story. Across all species, Strongyloides appeared in 137 records and Fasciola in 79, making them the dominant genera, while Trichuris, Eimeria, and Moniezia were also commonly detected. Among the smaller subset of records with species-level identification, Haemonchus contortus appeared in 18 records and Fasciola gigantica in 15. In cattle, F. gigantica and Schistosoma bovis were the most frequently reported species, while Fasciola, Strongyloides, and Eimeria dominated at genus level. In sheep and goats, H. contortus was the most frequently identified species, with Strongyloides and Trichuris prominent at genus level. These patterns point to strongyle-type nematodes in small ruminants and Fasciola species in cattle as priority targets for improved surveillance and integrated parasite management, particularly in areas with freshwater-snail habitats suitable for fluke transmission.

Perhaps the most sobering finding concerns what the evidence map does not show. Although sub-Saharan Africa encompasses 46 countries, the 111 eligible studies came from only 18, with roughly 73 percent originating from Ethiopia and Nigeria alone. No eligible published studies were identified from Angola, Guinea, Mali, Mozambique, or Sudan, among others. This absence should not be read as evidence of low parasite risk; rather, it reflects limited local surveillance, constraints in diagnostic capacity, limited international visibility of national research outputs, and the inaccessibility of unpublished reports and theses in languages other than English. The English-language eligibility criterion may have excluded relevant evidence from Francophone and Lusophone countries, local journals, government reports, and unpublished theses. The authors argue that countries with sparse evidence should be regarded as priority settings for representative baseline surveys rather than assumed low-risk areas.

Diagnostic limitations compound the geographic gaps. Flotation combined with sedimentation was the most frequently used method, appearing in 79 studies, followed by flotation alone in 19 and sedimentation alone in 10. These approaches are practical and field-applicable, but routine coprological examination often identifies eggs or oocysts only to broad taxonomic levels, particularly for strongylid nematodes. Consequently, genus-level identification dominated the evidence base, and the true species composition of gastrointestinal parasite communities across the region is likely largely unknown, fundamentally limiting the capacity to implement targeted, species-specific control strategies. The authors recommend that future studies report a minimum set of contextual variables, including season, agroecological zone, host details, production system, sample source, analytical detection threshold, and species-level identification, ideally adhering to the STROBE framework for observational studies to enhance transparency and reproducibility.

The implications ripple outward into economics, food safety, and even climate. Perry and colleagues previously ranked gastrointestinal parasite infection as a major poverty alleviation constraint for smallholder livestock keepers in sub-Saharan Africa, because infections depreciate animal condition and performance, limiting farmers’ chances to tap growing markets for animal-source foods. Yet clear and recent quantitative estimates of the impact of strongyle-type nematodes and Fasciola species on productive and reproductive performance in the region remain absent, leaving the true economic benefit of reducing prevalence unclear. Ruminants are also under increasing scrutiny as major emitters of enteric methane, and only one study to date has quantified the effect of gastrointestinal parasitism on methane emissions in sheep, despite the close relation between animal health, feed use efficiency, and greenhouse gas output. Improved parasite control could represent a low-cost co-benefit strategy for enhancing productivity while reducing emissions intensity.

The authors are careful about what their headline number means. The very broad prediction interval and extreme heterogeneity suggest the expected prevalence in any individual comparable setting could range from low to very high, so the 59.1 percent figure is best interpreted as a summary of the scale of the problem across the available evidence base rather than a substitute for locally representative surveillance. The review also focused exclusively on fecal-based diagnostics, excluding evidence generated solely through post-mortem inspection, serology, or other non-coprological methods, so the results describe fecal-detected parasitism rather than a complete estimate of infection or disease burden for all parasite taxa. Nevertheless, the sensitivity analyses strengthen confidence that frequent fecal detection of gastrointestinal parasites is not attributable solely to studies with greater risk of bias, and the persistence of moderate-to-high pooled estimates across all quality strata supports the conclusion that parasitism is a genuine and widespread constraint.

By mapping where fecal-based prevalence evidence is geographically sparse, diagnostically limited, or insufficiently resolved at species level, the study provides a foundation for the more representative surveillance and burden data needed to support Global Burden of Animal Diseases assessments of livestock disease impacts in the region. The authors call for representative surveillance in underrepresented settings, standardized diagnostics with improved species-level confirmation, and studies linking parasitism to productivity, economic loss, food safety, and anthelmintic resistance. For a region betting its food security on 1.1 billion ruminants, the message is clear: the parasites are there, they are measurable, and the first step to controlling them is knowing exactly where and what they are.

Subject of Research: Prevalence of fecal-detected gastrointestinal parasites in cattle, sheep, and goats across sub-Saharan Africa: a systematic evidence map and meta-analysis

Article Title: Prevalence of fecal-detected gastrointestinal parasites in cattle, sheep, and goats across sub-Saharan Africa: a systematic evidence map and meta-analysis

Article References: Bateki, C. A., Tielkes, S., & Schlecht, E. (2026). Prevalence of fecal-detected gastrointestinal parasites in cattle, sheep, and goats across sub-Saharan Africa: a systematic evidence map and meta-analysis. Frontiers in Veterinary Science, 13, Article 1984505. https://doi.org/10.3389/fvets.2026.1984505

Image Credits: AI Generated

DOI: 10.3389/fvets.2026.1984505

Keywords: Prevalence, fecal-detected, gastrointestinal, parasites, cattle, sheep, goats, across, sub-Saharan, Africa, systematic, evidence

The review, which analysed 72 studies in which tannin extracts or tannin-rich plant materials were added to concentrate or conserved feeds for ruminant animals, found that positive benefits were confirmed in 63 percent of cattle and cow studies and 54 percent of sheep and goat studies. These are not trivial numbers. In a field where feed additives routinely promise more than they deliver, a majority of trials reporting measurable gains for both beef and dairy cattle, as well as small ruminants, suggests that tannin supplementation has moved beyond the anecdotal stage and into the realm of reproducible nutritional intervention.

The mechanisms behind these benefits are chemically elegant. Tannins are polyphenolic compounds that bind proteins and other macromolecules through hydrogen bonding and hydrophobic interactions. In the rumen, this binding capacity can be harnessed rather than feared. By complexing with dietary proteins, tannins can slow the rate of protein degradation by rumen microbes, allowing more dietary protein to bypass ruminal fermentation and reach the small intestine, where it is digested and absorbed with greater efficiency. This shift in nitrogen metabolism reduces the excess ammonia that rumen microbes would otherwise convert and excrete, improving the efficiency with which dietary nitrogen becomes animal product rather than environmental pollutant.

Perhaps the most consequential benefit, however, lies in the rumen’s gas production. Methanogenesis, the microbial process by which archaea in the rumen convert hydrogen and carbon dioxide into methane, represents both a significant loss of dietary energy and a major source of agricultural greenhouse gas emissions. Tannins interfere with this process through multiple routes: they can directly inhibit methanogenic archaea, reduce the populations of protozoa that harbour methane-producing microbes in symbiotic association, and shift fermentation patterns toward pathways that produce less hydrogen gas as a by-product. The review identifies reduced methane emissions as one of the most likely benefits of tannin-containing diets for ruminants, a finding with obvious implications for the livestock sector’s climate footprint.

A second major benefit highlighted by the review concerns gut health, specifically the anthelmintic effect that certain tannins exert against gastrointestinal parasites. Condensed tannins in particular have been shown in numerous studies to reduce the establishment and fecundity of parasitic nematodes in the digestive tract of ruminants, offering a potential complementary tool in the face of growing anthelmintic resistance worldwide. For grazing and housed livestock alike, a feed additive that simultaneously improves protein utilisation, curbs methane output and lightens parasite burden represents a rare triple dividend in animal agriculture.

Yet the review is equally instructive about failure. In a substantial minority of ruminant studies, tannin supplementation produced no measurable benefit, and the authors identify several recurring reasons. The ‘wrong’ type or concentration of tannin is a primary culprit: hydrolysable tannins and condensed tannins differ fundamentally in structure and biological activity, and even within these broad classes, molecular weight and galloyl content vary enormously between sources such as chestnut, quebracho and grape pomace. Doses that are too low produce no effect, while doses that are too high can depress feed intake, bind essential nutrients indiscriminately and damage the rumen microbial community itself. An unsuitable combination of tannin type and concentrate composition can also negate any potential benefit, as can the developmental status of the animal, with young, growing or lactating animals responding differently to mature ones.

Another subtle complication arises from the complexity of plant extracts themselves. When tannins are sourced from crude plant by-products rather than purified extracts, the preparation contains a cocktail of other polyphenols, flavonoids, organic acids and residual compounds that may interact with, and in some cases cancel out, the effects of the tannins. The review notes that negation of tannin effects by other compounds in the extract is a recognised reason why some trials fail to reproduce the positive results seen elsewhere. This underscores a broader principle in animal nutrition: the biological activity of a feed additive cannot be predicted from its nominal label alone, but depends on the full chemical context in which it is delivered.

The picture for monogastric animals is considerably less rosy. The review examined 20 studies each for poultry and swine, and the results diverge sharply from the ruminant experience. In poultry, the inclusion of tannins in feed provided little nutritional benefit, although a notable exception emerged in the context of coccidiosis, a devastating intestinal disease caused by protozoal infection. Where coccidiosis severity was measured, tannin supplementation reduced infection, suggesting that the antimicrobial and anti-protozoal properties of tannins may find a targeted niche in poultry health management even where growth and feed efficiency gains are absent.

For pigs, the results were variable to the point of inconsistency. At low inclusion levels, tannin extracts often produced no appreciable influence on performance, while at higher levels they sometimes negatively impacted the nutritive value of the feed, presumably by binding dietary proteins and reducing their digestibility in the small intestine, where monogastric animals lack the ruminal microbial machinery that ruminants can deploy to liberate tannin-bound nutrients. In some cases, however, pig health was improved, hinting that the antimicrobial and antioxidant properties of tannins may still hold value in specific contexts, such as weaning transitions or disease challenge, even when growth benefits are elusive.

The overall conclusion of the review is unambiguous: tannin extracts appear to provide more benefit for ruminants than for monogastrics, particularly poultry. This asymmetry makes biological sense, since the rumen is precisely the environment where tannin chemistry can be exploited to modulate fermentation, protein flow and microbial populations, whereas the simple stomach of a pig or chicken offers fewer opportunities for such manipulation and greater vulnerability to anti-nutritional effects. Looking forward, the authors raise an intriguing question: if tannin supplementation of concentrate feeds continues to prove beneficial, would it be advantageous to breed or engineer the main ingredients of those concentrates, such as maize or soybean, to express tannins natively? Such an approach could embed the benefits directly into the feed matrix, though it would also raise new questions about dose control, digestibility trade-offs and the interaction of endogenous tannins with other feed components. For now, the evidence points to a clear division of labour: tannins belong, first and foremost, in the rations of cattle, sheep and goats, where their capacity to improve protein utilisation, reduce methane emissions and support gut health through anthelmintic action offers livestock producers a natural, plant-derived tool with measurable and multifaceted returns.

Subject of Research: Review of tannin supplementation in concentrate diets for ruminant and monogastric livestock

Article Title: Benefits of tannin added to concentrate diets fed to ruminants and monogastric livestock

Article References: Caradus, J. R. (2026). Benefits of tannin added to concentrate diets fed to ruminants and monogastric livestock. Frontiers in Animal Science, 7, Article 1905042. https://doi.org/10.3389/fanim.2026.1905042

Image Credits: AI Generated

DOI: 10.3389/fanim.2026.1905042

Keywords: tannins, ruminants, cattle, sheep, goats, poultry, swine, methane emissions, gut health, anthelmintic, feed additives, polyphenols

The review, led by Anand Jejal and colleagues at the ICAR-National Dairy Research Institute in Karnal, India, synthesised evidence from a systematic search of the Scopus database covering the years 2000 to 2026. After applying strict eligibility criteria, the team distilled the field down to 17 core studies that explicitly examined ramie as feed, including in vivo feeding trials in ruminants, in vitro rumen fermentation experiments and agronomic assessments of forage management. The authors screened titles and abstracts independently, resolved disagreements through discussion, and followed the PRISMA 2020 reporting guidelines. They deliberately excluded studies focused purely on textile processing or on phytoremediation, the use of plants to extract heavy metals from contaminated soil, unless the biomass had also been evaluated for feeding purposes. A bibliometric keyword co-occurrence analysis using VOSviewer software revealed three dominant research themes: nutritional evaluation and digestibility, zootechnical performance in animals, and rumen fermentation dynamics.

Botanically, ramie is a vigorous perennial herb native to East Asia, propagated mainly through rhizome cuttings or root division rather than seed. This vegetative propagation confers a practical advantage for forage producers: genetic uniformity across the stand, which translates into consistent biomass quality from harvest to harvest. The crop thrives in warm, humid conditions with optimal temperatures between 25 and 30 degrees Celsius, and under intensively managed tropical fodder systems it can be cut up to 14 times per year, with upper-bound yields reaching approximately 300 tonnes of fresh material, or about 42 tonnes of dry matter, per hectare annually. The authors caution that these figures represent the ceiling of what has been achieved under specific climatic and management conditions rather than typical farm-level outputs. Ramie’s deep and extensive root system allows it to extract subsoil water during dry spells, and its capacity for osmotic adjustment helps it tolerate moderate drought, traits that give it a yield-stability edge over alfalfa, Napier grass and maize when water becomes limiting.

The nutritional case for ramie rests on a strikingly good chemical profile. Crude protein content in whole-plant forage generally falls between 15 and 24 percent of dry matter, placing it well above most tropical grasses and in the same league as high-quality legumes such as lucerne. Leaf-rich samples harvested on a 30-day interval have even approached 29 percent crude protein on a dry-matter basis. In vitro dry matter digestibility values range from 55 to 70 percent, depending on cultivar, harvest interval and plant part, while estimated metabolizable energy contents fall between 8.5 and 10.5 megajoules per kilogram of dry matter. The fibre fractions are moderate, with neutral detergent fibre between 45 and 60 percent and acid detergent fibre between 30 and 40 percent, enough to support rumination without depressing intake. The mineral profile is less straightforward: calcium is often abundant, exceeding 0.8 percent of dry matter, but phosphorus is comparatively low, producing a wide calcium-to-phosphorus ratio that demands careful ration formulation, particularly for high-producing dairy animals.

One of the most intriguing aspects of ramie’s chemistry is its content of condensed tannins, secondary plant compounds with a double-edged nutritional role. At moderate concentrations, tannins bind to dietary protein in the rumen and shield it from excessive microbial degradation, increasing the flow of so-called bypass protein to the small intestine, where it can be absorbed directly by the animal. This mechanism effectively upgrades the quality of the protein the animal derives from the feed. At high concentrations, however, tannins can reduce palatability and overall digestibility. The review found that other anti-nutritional compounds, including oxalates and saponins, are present only at low levels in the studies examined, and no toxicity has been reported at the dietary inclusion rates evaluated to date. Post-harvest processing such as ensiling or drying can further reduce these compounds, and fermentation during ensiling appears to mellow bitter-tasting secondary metabolites while stabilising key nutrients, which in turn increases voluntary intake.

The animal performance data are where ramie’s potential becomes tangible. In sheep and goats, voluntary dry matter intake of ramie-based diets has generally ranged between 2.5 and 3.5 percent of body weight in the reviewed trials, comparable to lucerne-based diets and typically higher than diets dominated by tropical grasses such as Napier grass. Partial replacement of conventional roughage with ramie increased average daily gain in growing goats by 12 to 18 percent, while lambs fed diets containing up to 30 percent ramie achieved daily gains of 160 to 180 grams. In dairy goats, replacing 25 percent of the forage component with ramie raised milk yield by 8 to 10 percent and increased concentrations of milk protein and fat. There is a clear ceiling, though: inclusion rates above 40 percent have been associated with off-flavours in milk, likely caused by the transfer of specific phenolic compounds into the milk fat, and growth performance declined in goats when dried whole-plant ramie replaced more than 35 percent of dietary alfalfa.

Beyond growth and milk, ramie appears to influence rumen function and animal health in subtler ways. Feeding studies have reported that ramie helps maintain rumen pH within the normal physiological range and increases total volatile fatty acid concentrations, the primary energy currency of the ruminant host. Blood metabolite profiles in the reviewed trials remained normal, suggesting no adverse health effects at moderate inclusion levels. Emerging in vitro work adds an environmental dimension: ramie silage lowered methane production relative to corn silage in fermentation studies, although fibre degradability declined once its inclusion exceeded 40 percent of dietary dry matter. The leaves are also rich in bioactive compounds with documented antibacterial, antiviral, antioxidant and anti-inflammatory activities. Evidence from non-ruminant species supports these functional effects, with ramie leaf powder improving antioxidant status and growth in ducks, enhancing yolk colour and fatty acid profile in laying hens, and improving carcass traits in pigs at low inclusion levels.

The review is candid about the crop’s vulnerabilities and the gaps in the evidence base. Ramie remains susceptible to economically significant pests and diseases, including the ramie moth, stem borers, anthracnose and root rot, and current control strategies lean heavily on chemical inputs that risk toxic residues in forage and inflate production costs. Forage-specific cultivars bred for resistance and quality are scarce, since breeding programmes have historically targeted fibre traits. Perhaps the most striking caveat concerns the plant’s remarkable ability to hyperaccumulate heavy metals such as zinc, cadmium and lead from contaminated soils. While this makes ramie a powerful tool for cleaning up mine sites and polluted land, it creates a serious toxicological hazard if such biomass enters the feed chain. The authors stress that ramie grown for phytoremediation must be strictly excluded from livestock diets, and that a clear separation must be maintained between remediation plantings and forage production on uncontaminated ground.

The authors conclude that ramie’s combination of agronomic adaptability, nutritional quality and multifunctionality makes it a promising candidate for climate-smart livestock systems, but they are equally clear that the current literature is fragmented. Most studies have been conducted under controlled conditions or in limited geographic regions, long-term feeding trials under commercial conditions are lacking, and farm-level economic analyses and life-cycle assessments are almost entirely absent, preventing definitive recommendations for large-scale producers. Standardised guidance on nutrient management, harvesting intervals and dietary inclusion levels is needed to reduce the variability in forage quality that currently complicates year-round feeding strategies. The research roadmap the authors propose spans forage breeding programmes, mechanistic studies of rumen microbiome dynamics and methane mitigation, and rigorous sustainability accounting. If those gaps can be filled, an ancient fibre crop may find a new role at the intersection of animal nutrition and climate resilience, turning a plant once grown for cloth into a cornerstone of feed security for the world’s small ruminants.

Subject of Research: Ramie (Boehmeria nivea) as a high-protein forage crop for small ruminant nutrition and climate-resilient livestock production

Article Title: Boehmeria nivea (Ramie) as a high protein forage crop for small ruminants focusing on agronomic potential, nutritive value, and animal performance

Article References: Jejal, A., Saxena, A., Singh, M., Saraswat, P. K., Mondal, G., & Kumar, S. (2026). Boehmeria nivea (Ramie) as a high protein forage crop for small ruminants focusing on agronomic potential, nutritive value, and animal performance. Discover Plants, 3(1), Article 453. https://doi.org/10.1007/s44372-026-00928-y

Image Credits: AI Generated

DOI: 10.1007/s44372-026-00928-y

Keywords: ramie, Boehmeria nivea, forage crop, small ruminants, goats, sheep, crude protein, drought tolerance, rumen fermentation, climate-smart agriculture, animal performance, sustainable livestock

Contagious caprine pleuropneumonia, commonly abbreviated CCPP, is caused by the bacterium Mycoplasma capricolum subsp. capripneumoniae, often shortened to Mccp. The organism targets the lungs and chest cavity of goats and, less dramatically, sheep, producing a severe fibrinous pleuropneumonia that can sweep through a flock with devastating speed. Under outbreak conditions, morbidity can reach one hundred percent of susceptible animals, and mortality has been recorded at rates between eighty and one hundred percent. The disease is considered a classical transboundary animal disease, spreading across borders with the movement of live animals, and it imposes heavy economic costs through deaths, reduced meat and milk output, treatment expenses, and restrictions on trade in small ruminants and their products. Although the presence of CCPP has long been suspected in Ethiopia, particularly in regions bordering Sudan and Kenya, comprehensive data from many districts have remained scarce, leaving national control strategies built on incomplete maps of where the pathogen circulates.

To address one of those gaps, researchers led by Amanuel Balemi Lemecha, working with colleagues at Ambo University and the Animal Health Institute, carried out a seroepidemiological investigation between November 2022 and September 2023 in three districts of West Shewa Zone: Dandi, Ejere, and Meta Robi. The zone, whose administrative capital Ambo lies about 114 kilometers west of Addis Ababa, supports a large small ruminant population managed predominantly under mixed crop-livestock systems, in which sheep and goats graze communal lands together and share overnight shelters. The team selected the districts purposively based on livestock market activity, animal movement patterns, and small ruminant production potential, then chose five peasant associations within each district and sampled individual animals randomly from households.

The study population consisted of 433 animals, comprising 284 goats and 149 sheep, all older than six months, apparently healthy at sampling, and with no history of CCPP vaccination during the preceding two years, a fact verified against official district veterinary records and owner reports. From each animal, the researchers collected five to seven milliliters of blood from the jugular vein, allowed the samples to clot overnight, separated the serum, and stored it at minus twenty degrees Celsius until analysis. Antibodies against Mccp were detected using a competitive enzyme-linked immunosorbent assay, or c-ELISA, performed at the Animal Health Institute with a commercial kit recommended by the Food and Agriculture Organization’s world reference center for CCPP. The assay, which boasts a specificity of 99.9 percent, works by measuring the percentage of inhibition of a monoclonal antibody’s binding to Mccp antigen coated on microplate wells; samples showing inhibition of fifty-five percent or greater were classified as positive.

The results revealed an overall seroprevalence of 19.4 percent, meaning 84 of the 433 animals had been exposed to the pathogen at some point. The species difference was striking. Goats recorded a seroprevalence of 26.8 percent, a figure that sits close to the national pooled estimate of 25.7 percent derived from a previous meta-analysis of Ethiopian studies, while sheep showed only 5.4 percent, consistent with the well-documented pattern in which goats are the primary and most susceptible host and sheep frequently serve as subclinical or spillover hosts that can nonetheless carry the organism. Seroprevalence also climbed with flock size, rising from 13.3 percent in small flocks of one to ten animals, to 16.9 percent in medium flocks of eleven to twenty, and reaching 30 percent in flocks exceeding twenty head. Geographically, the lowland district of Meta Robi recorded the highest seropositivity at 25.6 percent, compared with lower figures in the midland district of Dandi and the highland district of Ejere, a gradient the authors attribute in part to ecological differences and the more frequent livestock movement that seasonal shortages of feed and water impose on lowland herds.

To identify which factors independently predicted infection, the researchers applied univariable and multivariable logistic regression, retaining variables with a p-value below 0.25 in the initial screen and checking for multicollinearity before fitting the final model, whose calibration was confirmed by a non-significant Hosmer-Lemeshow goodness-of-fit test. Three risk factors emerged as significant. Species was the strongest: goats had roughly five and a half times the odds of seropositivity compared with sheep, with an adjusted odds ratio of 5.5 and a 95 percent confidence interval spanning 2.523 to 12.202. Management system mattered as well, with animals kept under extensive systems, in which flocks graze and browse freely and mix with neighboring herds, showing about 2.8 times the odds of infection relative to intensively housed animals. Finally, the origin of the animal proved decisive: goats and sheep purchased from markets were approximately 2.7 times more likely to be seropositive than animals born within the flock, a pattern consistent with newly acquired animals acting as asymptomatic carriers or succumbing to infection after the stress of transport and adaptation suppresses their immunity.

While the laboratory work was underway, the team administered a semi-structured questionnaire to 110 randomly selected small ruminant owners across the three districts, conducting interviews in the local language, Afan Oromo, after obtaining verbal informed consent and pretesting the instrument on five percent of the sample size in a neighboring agro-ecologically similar area. The demographic picture was dominated by farming households, with about eighty percent of respondents identifying as farmers and nearly four in five of those being male. When asked to rank the most common diseases of their sheep and goats, respondents placed peste des petits ruminants first at thirty percent, followed by orf at 28.2 percent, with CCPP third at twenty percent, suggesting the disease registers as a familiar clinical syndrome even where its formal identity does not.

The awareness data, however, were sobering. About 91.8 percent of respondents reported having never heard of CCPP by name, and 87.3 percent said they do not vaccinate their animals against it. The researchers suggest this disconnect arises partly from the use of generic local descriptors for respiratory illness, which masks the specific pathogen. In Meta Robi and Dandi, farmers locally recognize the syndrome as Michi Somba, meaning a disease that affects the lung, echoing the diversity of vernacular names documented elsewhere in Ethiopia, including Sombesa in Fentale, Sompo in Hammer and Benna-Tsemay, and Zom in Gambella. Despite the absence of consistent nomenclature, a majority of farmers could recognize the disease from its clinical signs: 62.7 percent reported that it causes death and spreads from animal to animal, and 61.8 percent identified the introduction of new animals from markets as a source of transmission. Husbandry practices amplify the risk, with 80.9 percent of respondents practicing communal watering and feeding and routinely managing sheep and goats together, facilitating close interspecies contact. On the treatment side, ninety percent of farmers use modern veterinary drugs, while only 6.4 percent rely on traditional remedies, but 78.5 percent cited a lack of drugs and vaccines as the principal barrier to preventing or treating disease in their flocks.

The authors acknowledge limitations, including the restriction of the study to three districts, the potential for recall and social desirability bias in the questionnaire responses, and the absence of molecular characterization of the circulating Mccp strains. Even so, the study delivers the first baseline seroprevalence data for CCPP in West Shewa Zone and confirms that the pathogen is firmly entrenched there. The researchers recommend strengthening disease surveillance, implementing targeted vaccination programs, quarantining newly purchased animals before they join flocks, and improving farmer education so that awareness of the disease catches up with its biological footprint. Future work incorporating PCR and bacterial sequencing, they note, will be essential to unravel the transmission dynamics of Mccp in the region and to design control interventions that are both context-specific and sustainable for the smallholder systems on which millions of Ethiopian households depend.

Subject of Research: Seroepidemiology of contagious caprine pleuropneumonia and farmers' awareness in West Shewa Zone, Ethiopia

Article Title: Seroepidemiology of contagious caprine pleuropneumonia (CCPP) and farmers’ awareness and management practices in selected districts of West Shewa Zone, Oromia, Ethiopia

Article References: Lemecha, A. B., Bune, W. M., Ogeto, A. B., & Dinbiso, T. D. (2026). Seroepidemiology of contagious caprine pleuropneumonia (CCPP) and farmers’ awareness and management practices in selected districts of West Shewa Zone, Oromia, Ethiopia. Discover Animals, 3(1), Article 82. https://doi.org/10.1007/s44338-026-00246-3

Image Credits: AI Generated

DOI: 10.1007/s44338-026-00246-3

Keywords: CCPP, Mycoplasma capricolum subsp. capripneumoniae, seroprevalence, goats, sheep, Ethiopia, small ruminants, risk factors, c-ELISA, farmers' awareness, vaccination, West Shewa Zone