Peste des Petits Ruminants (PPR) is one of the major transboundary animal diseases that severely impact livestock production and trade worldwide. An investigation was carried into the seroprevalence and risk factors of PPR in small ruminants, camels, and wild ruminants in Bahrain. A total of 1240 serum samples were collected from 119 sheep flocks and 1224 serum samples from 125 goat herds. In addition, 100 sera from camels and 38 sera from wild ruminants, were collected. Serum samples were tested for the presence of PPR specific antibodies using a competitive ELISA. Flock management and health information of the flocks and herds were collected using a semi-structured questionnaire. The individual prevalence of PPR in sheep and goats was 26% and 25.5%, respectively. The flock or herd level prevalence of PPR was 22.7% and 29.6% in sheep and goats, respectively. None of the tested camels or wild ruminants were positive for PPR-specific antibodies. Sheep and goats from the Northern governorate were more likely to be seropositive to PPR than in other governorates. On the individual animal level, the univariate analysis suggested; age (<12 months), sex (male), and health status (weak animals) as risk factors for PPR seropositivity. On the flock/herd level, the multivariable logistic regression analysis identified large flock/herd size and semi-intensive farming as risk factors for PPR seropositivity.

This study explored techniques with enteric methane (CH4) abating potential, ranging from chemical additives including 3-NOP, nitrate, and halogenated compounds to natural feed additives such as tannins, oils, seaweed extracts, and probiotics. Most of the evaluated strategies exert their influence either by promoting the growth of ruminal microbes that compete with methanogens for metabolic hydrogen as their resource or by directly consuming CH4. Additionally, externally supplied probiotics, including propionate-forming bacteria and methane-oxidizing bacteria, are a promising tool. However, challenges persist in implementing these strategies effectively. High doses of chemical additives and plant based secondary metabolites often achieve significant CH4 reduction, but they are associated with negative impact on dry matter intake and digestibility, thus compromising overall animal performance. On the other hand, using lower doses to maintain animal performance may not achieve beneficial CH4 reduction. Furthermore, concerns about the impact of certain additives on human health have led to a shift towards more natural alternatives, but their efficacy and feasibility in vivo necessitate further evaluation. Comprehensive research that integrates data from diverse global experiments on ruminants through meta-analytical approaches is essential. Such research will help in identify strategies that either reduce methane emissions and/or enhance production performance, ensuring sustainable livestock farming practices. In conclusion, mitigating CH4 emissions from ruminant livestock is a complex challenge with wide-ranging implication.

Verminosis causes great damage to the producer, with reduced milk production and decreased development of young animals. The use of bioproducts are an alternative to control worms. This study evaluated the effects of oral administration of one commercial formulations, based on the fungus Duddingtonia flagrans (Bioverm®) and experimental formulations D. flagrans associated with Pochonia chlamydosporia, on the control of worms in naturally infected cattle on February pasture to October 2021. Eighteen Holstein x Zebu cattle were divided into groups of six animals (group 1 Bioverm®, group 2 Association and control), separated into paddocks naturally infected with helminth larvae (L3). The parasite load was by means of fecal samples and pasture collection to determine L3 infestation. The study demonstrated low recovery of L3 in the pasture due to low rainfall during the experiment. The EPG was lower in groups 1 and 2 compared to the control in April, May and July, while in March the values were lower only in treatment 1 compared to the control. Individual or combined administration of fungal products reduced the presence of eggs and larvae in pastures at certain months of the year, indicating their effectiveness in the strategic control of gastrointestinal parasites in cattle.

Medical and translational scientific research requires the use of animal models as an initial approach to the study of new therapies and treatments, but when the objective is an exploration of translational potentialities, classical models fail to adequately mimic problems in humans. Among the larger animal models that have been explored more intensely in recent decades, small ruminants, namely sheep and goats, have emerged as excellent options. The main advantages associated to the use of these animals in research works are related to their anatomy and dimensions very similar to those of humans in most physiological systems, in addition to their low maintenance and feeding costs, tendency to be docile, long life expectancies and few ethical complications raised in society. The most obvious disadvantages are the significant differences in some systems such as the gastrointestinal, and the reduced amount of data that limits the comparison between works and the validation of the characterization essays. Despite everything, recently these species have been increasingly used as animal models for diseases in different systems, and the results obtained open doors for their more frequent and advantageous use in the future. The purpose of this review is to summarize the general principles related to the use of small ruminants as animal models, with focus on regenerative medicine, to group the most relevant works and results published recently and to highlight the potentials for the near future in medical research.

Starch is considered a major nutritional factor of maize (Zea mays L.) kernels, and can be influenced by the type of endosperm. The effects of endosperm type (vitreous and non-vitreous) and type of soil (clay and sand) on the starch content of kernels of maize, and on the in vitro degradation of starch were investigated in the rumen fluid after harvesting at 6 different maturity stages during 2008 and five different maturity stages in 2009. Starch degradation, in rumen fluid, was determined after 6 h, 12 h and 20 h of incubation, using the technique of gas production. A positive linear relationship was observed during gas production (ml gas/g organic matter) and starch degradation (g kg^-1 starch) at all incubation times, with starch contents of maize kernels to a certain limit of starch accumulation (i.e. at starch contents 451-519 g/kg OM) and negative relationship afterwards. This suggests significant effects of maturity on ruminal starch degradation of maize kernels. At each harvest date, ruminal starch degradation of maize kernels was affected by crop genotype as well as soil type. The in vitro ruminal degradation potential of starch in maize kernels was influenced by the nature of the endosperm, with a higher degradation of non-vitreous kernels than of vitreous kernels. The rumen starch degradation was also influenced by type of soil, with better degradation on clay than sandy soil. For all the incubation times and maturity stages the effects of genotype, soil type and maturity stage were consistent in rumen fluid.

PPR is a highly contagious viral disease and one of the deadliest affecting wild goats, sheep and small ruminants, however goats are generally more sensitive. The causative agent is the Peste des Petits Ruminants virus (PPRv) which is a single-stranded RNA virus of negative polarity belonging to the Paramyxoviridae family. In February 2020, an active outbreak of PPR was re-ported in a herd of a transhumant farmer in the village of Ngainth Pathé (department of Kounguel, Kaffrine region,Senegal). Of the ten (10) swabs collected from goats, eight (8) came back positive by real-time PCR. The most positive sample was amplified, purified and amplicon sent for sequencing. Phylogenetic analysis showed that the sequence of the PPR virus obtained belonged to lineage IV. These results confirm those found in the latter countries and reinforce the hypothesis of the importance of animal mobility between these neighboring countries. In perspective, following the discovery of this lineage IV in Senegal, a study on its dispersion is underway throughout the national territory. The results that will emerge from this study, asso-ciated with detailed data on animal movements and epidemiological data, will provide appro-priate and effective information to improve PPR surveillance and control strategies with a view to its eradication.

In this article, we first assessment of peste des petits ruminants (PPR) antibodies in vaccinated pregnant ewes of Kazakh breed fine-fleeced immunized with the PPR vaccine and the duration of maternal immunity in their lambs. Ewes in the last trimester of pregnancy of gestation were immunized with a vaccine from the Nigeria 75/1 strain of the PPR virus (PPRV) produced by the Research Institute of Biological Safety Problems (RIBSP), Kazakhstan. Serum samples from lambs born from vaccinated and unvaccinated ewes were collected a week after birth and at intervals of 7 days for 18 weeks after birth. Serum samples collected from lambs were tested for PPR antibodies using competitive ELISA and Virus neutralization test (VNT). Maternal antibodies (MAs) in lambs born from vaccinated ewes were detected up to 18 weeks with a tendency to decrease starting at week 14 and by the end of the experiment receded below the protective level (<1:8). In the blood serum of a 14-week-old lamb with MAs (1:8), post vaccination with a field dose (103 TCID50) of the vaccine against PPR, the titers of protective antibodies to the PPRV increased to 1:16 on 14 day post vaccination and lamb protected from infection upon field PPRV. A lamb of the same age with MAs in the 1:8 titer was 100% protected from infection with the field PPRV. Therefore, it is recommended that lambs of the Kazakh fine-wool breed be immunized from the age of 14 weeks or older to avoid a period of susceptibility.

The Gram-negative, strictly anaerobic bacterium Megasphaera elsdenii was first isolated from the rumen in 1953 and is common in the mammalian gastrointestinal tract. Its ability to use either lactate or glucose as its major energy source for growth has been well documented, although it can also ferment amino acids to ammonia and branched-chain fatty acids, which are growth factors for other bacteria. The ruminal abundance of M. elsdenii usually increases in animals fed grain-based diets due to its ability to use lactate (the product of rapid ruminal sugar fermentation), especially at low ruminal pH (< 5.5). M. elsdenii has been proposed as a potential dietary probiotic to prevent ruminal acidosis in feedlot cattle and high-producing dairy cows. However, this bacterium has also been associated with milk fat depression (MFD) in dairy cows, although proving a causative role has remained elusive. This review summarizes the unique physiology of this intriguing bacterium, and its role of in ruminal community function and in the health and productivity of the host animal. In addition to its effects in the rumen, the ability of M. elsdenii to produce C2-C7 carboxylic acids – potential precursors for industrial fuel and chemical production, is examined.

Large ruminant production in developing countries is inefficient with low growth rates and likely high greenhouse gas emissions (GHGe) per unit of meat or milk produced. Trials conducted in Lao PDR from 2017-2020, studied ad-libitum supplementation for 12 weeks with 20kg high quality molasses nutrient blocks (MNB; Four Seasons Pty Ltd, Brisbane, Australia), that were either: non-medicated (NMB); fenbendazole-medicated (FMB5, Panacur100®, Coopers Australia, @ 5g/kg); triclabendazole-medicated (TMB5 or TMB10, Fasinex®, Novartis Australia, @ 5g/kg or @ 10g/kg, respectively); or formulated with urea (UMB8 or UMB10 @ 8% or 10% urea, respectively). Average daily gains (ADG) were determined for access to all MNB’s and compared with access to NMB’s, no supplementation, or previously determined free-grazing baseline ADG’s (55–84g in cattle; 92–106g in buffalo). ADGs were significantly improved following access to all MNBs for periods up to 12wks. ADGs following access to UMB8 or NMB were calculated for three age cohorts of cattle: young calves <8m (238-298g), growing cattle (143-214g) and lactating cows (179-191g). Modelling using IPCC Inventory software model V 2.69 of published data demonstrated a conservative net abatement of 350kg CO2e was achievable over a 200 day feeding period. An additional trial of Emissions control blocks (EMB’s, n = 200) distributed to farmers (n = 60) and two educational institutions, was conducted. Consumption rates (156g/day) and farmer and institutional acceptance of EMB’s were similar to published findings with other MNB’s, confirming all MNB’s and EMB’s improved animal productivity and body condition score, with healthier animals that were easier to manage. Modelling of changes in GHGe intensity identified an abatement of 470kg CO2e per EMB consumed, delivering a total project emissions abatement of 94t CO2e. Provision of MNBs and EMBs in smallholder large ruminant production systems is likely to achieve impressive abatement of GHGe due to improved efficiency of rumen fermentation and productivity.

A systematic review and meta-analysis were conducted to estimate the prevalence of chlamydiosis in small ruminants. The study included 133 publications that reported the presence of Chlamydia abortus in 109 and 74 studies in sheep and goats from 45 countries. The prevalence of chlamydiosis was estimated at global, regional, and national levels using meta-analyses of proportions. Meta-regression and cumulative meta-analyses were also performed. Globally, the prevalence of chlamydiosis in sheep and goats was estimated at 20.1% (95% CI: 17.8-22.4) and 14.4% (11.6-17.4), respectively. For sheep, chlamydiosis prevalence was heterogeneous at regional and national levels. South Asia had the highest prevalence (30.6%) and East Asia and Pacific the lowest (14.0%). Nationally, chlamydiosis was more prevalent in Romania, Hungary, and Germany (range 53.3-87.0%) compared to Costa Rica, Australia, and Zimbabwe (4.7-5.2%). Among goats, chlamydiosis prevalence was similar across regions (10.4-19.7%), but varied significantly among countries, 0.0% in Romania and Australia and 91.7% in Bosnia and Herzegovina. In both species, sample size, number of diagnostic techniques, and latitude were significant covariates. Prevalence varied widely in the first decades of publications before stabilizing. Our study found a high prevalence of chlamydiosis in small ruminants, with the pathogen being distributed globally but heterogeneously across countries.

In the struggle for survival, all organisms have evolved adaptations for protection from predation. Angiosperms are among the most abundant producers on the planet, but they are trapped in a precarious symbiosis with animals for pollination and fruit dispersal, while also having to deter herbivory. About 10% of all angiosperms produce the deterrent latex from ubiquitous isoprene precursors. Latex is an aqueous suspension of rubber particles and other compounds which works as an antifeedant by clogging chewing mouthparts and by coagulating into a solid in stomach acid. A survey of stomach pHs from various animals supports the hypothesis that foregut-fermenting ruminants have evolved the capacity to evade latex coagulation due to the presence of anterior digestive chambers with near-neutral to alkaline pH before it enters the acidic abomasum. Hindgut-fermenting animals lack this adaptation and have to eat forage which is low in latex, such as grasses. The latex-adaptive foregut browsers vs. latex-maladapted hindgut grazer hypothesis has implications for both livestock and zoo animals which may be provided with forage that is not optimal for their gut health. Further, ruminants and herbivorous tadpoles are at risk for damage by popular bioinsecticides such as Bt which are activated by alkaline gut pH.

This paper analyzes the mitigation of enteric methane (CH4) emissions from ruminants with the use of feed additives inhibiting of rumen methanogenesis to limit global temperature increase to 1.5 °C. A mathematical simulation conducted herein predicted that pronounced inhibition of rumen methanogenesis with pure chemicals or bromoform-containing algae can contribute to limit global temperature increase by 2050 to 1.5 °C only if widely adopted at a global level and considering an efficacy higher than obtained in most studies. Currently, the most important limitations to the adoption of antimethanogenic feed additives are probably increased feeding cost without a consistent return in production efficiency, and achieving sustained delivery of inhibitors to the rumens of non-supplemented, extensively ranging animals. Economic incentives, and changes in rumen microbial metabolism caused by inhibiting methanogenesis, could potentially be used to make the methanogenesis inhibition intervention cost effective. Also, the composition of the methanogenic community, and rate of disappearance of inhibitors of methanogenesis in the rumen can influence the effective dose of the inhibitors, and hence the cost of their adoption. Possible means for sustained delivery of antimethanogenic compounds to extensively grazing animals are discussed. Limitations and knowledge gaps of these approaches, and future research directions, are examined.

The relationship between DM yield/cutting and fermentable organic matter (FOM) content of tropical grasses was appropriately investigated to re-access optimal grass maturity to feed dairy cattle. Nine different grass species belonging to the genera: Brachiaria spp. (Mulato II, Ruzi), Panicum spp. (Guinea, Hamil, Mombasa, TD58), and Pennisetum spp. (King, Napier, VA06) were chemically analyzed and subjected to an in vitro gas production (IVGP) test. For 72 h, gas production (GP) was continuously recorded with fully automated equipment. A triphasic, nonlinear, regression procedure was applied to analyse GP profiles. Across all the grasses, it was found that the neutral detergent fiber (NDF) contents increased with increasing maturity of the grass while the CP contents decreased with increasing NDF contents. In all nine grasses, digestible organic matter (dOM) was significantly affected by the week of cutting but IVGP was similar between weeks of cutting in Ruzi, Hamil, Mombasa, and Napier grass. Except for Guinea grass, the lowest dOM values were found when the grasses were cut after ≥ 5 weeks of regrowth. Harvesting grass one or two weeks earlier than normal cutting time is a practically relevant intervention in in-creasing forage quality and productivity of dOM and fermentation potential.

About 10% of angiosperms, an estimated 20,000 species, produce latex from ubiquitous isoprene precursors. Latex, an aqueous suspension of rubber particles and other compounds, functions as an antifeedant and herbivory deterrent. Here, I propose that the solubility of latex in neutral to alkaline pH supports the hypothesis that foregut-fermenting herbivores such as ruminants, kangaroos, sloths, insect larvae and tadpoles have evolved to adapt to the ingestion of latex with the evolution of alkaline anterior digestive chamber(s). However, they consequently become susceptible to the action of Bacillus thuringiensis (Bt) -endotoxin and related bioinsecticides which are activated in alkaline environments. By contrast, hindgut-fermenting herbivores such as horses and rabbits have acidic anterior digestive chambers in which latex coagulates and may cause gut blockage, but in which Bt is not activated. The latex-adapted foregut herbivore vs. latex-maladapted hindgut herbivore hypothesis developed in this paper has implications for foregut-fermenting husbanded livestock and zoo animals which may be provided with latex-containing forage that is detrimental to their gut health. Further, ruminants and herbivorous tadpoles with alkaline anterior chambers are at risk for damage by the supposedly “environmentally-friendly” Bt bioinsecticide which is widely disseminated, or engineered into crops which may enter animal feed streams.