Small Ruminants Research Articles

Household Economic Losses and Community Knowledge Determine Control Strategies: A Case of Cerebral Coenurosis in Small Ruminants in Northern Tanzania

Cerebral coenurosis affects sheep and goats worldwide and has zoonotic implications. Information on the financial burden and understanding of the disease and control practices may inform control strategies. A cross-sectional study was conducted in Babati and Ngorongoro Districts, Tanzania, to determine economic losses, farmers’ knowledge, and attitudes and practices on the control of coenurosis in small ruminants. A structured questionnaire was administered to 558 households for data collection. The total annual loss was TZS 122.8 M (USD 52.9 K) for Babati and TZS 656.5 M (USD 282.9 K) for Ngorongoro District. The average annual household financial loss was TZS 356.8 K (USD 153.83) for Babati and TZS 3.1 M (USD 1.3 K) for Ngorongoro District. Almost 90% of respondents were aware of coenurosis while less than 1% of the respondents had no knowledge of it at all. The average knowledge score was 5.85 out of 16 (36.6%), which implies a low level of knowledge on coenurosis. About 94% of respondents showed a willingness to participate and pay the control costs. Given the economic loss and favorable attitudes toward control participation, delivery of an educational package on epidemiology and control of coenurosis to livestock keepers may trigger collaborative and sustainable intervention.

Moringa leaf meal exerts growth benefits in small ruminants through modulating the gastrointestinal microbiome

This study investigated the impact of feeding 17% moringa leaf meal (MLM) on the ruminal and fecal microbial composition and body weight gain (BWG) performance of lambs (Ovis aries) and kids (Capra hircus). A total of n = 28 lambs (n = 14, no-moringa, n = 14, 17% moringa) and 24 kids (n = 12, no-moringa, n = 12, 17% moringa) were involved in the experiment and body weight was recorded fortnightly. Metagenomic shotgun sequencing was performed on 28, 22, and 26 ruminal solid, liquid fraction, and fecal samples from lambs, and 23, 22, and 23 samples from kids. Moringa supplementation significantly increased BWG in lambs (21.09 ± 0.78 to 26.12 ± 0.81 kg) and kids (14.60 ± 1.29 to 18.28 ± 1.09 kg) (p-value ≤ 0.01). Microbiome analysis revealed an elevated Firmicutes:Bacteroidetes ratio in the moringa diet group. Moringa-fed animals exhibited increased microbial genera associated with volatile fatty acids (VFAs) production (Prevotella, Anaerovibrio, Lachnospiraceae, Butyrivibrio, Christensenella) and starch and fiber digesters (Proteobacteria, Ruminococcus). The increase in the bacterial genus Sharpea suggested possible methane reduction and decreased proportion of pathogens, Aliarcobacter_ID28198, Campylobacter_ID194 and Campylobacter_ID1660076 suggest health benefits. Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis demonstrated significant alterations in microbial gene pool and metabolic pathways related to carbohydrate, protein, lipid and energy metabolism, indicating potential improvements in animal health. Overall, moringa feeding showed higher energy recovery, improved growth, and potential benefits in methane reduction and reduced pathogenic bacteria.

Production of highly soluble and immuno-reactive recombinant flagellin protein of Clostridium chauvoei

ObjectiveFlagellin protein, an integral component of flagella, provides motility to several bacterial species and also acts as a candidate antigen in diagnostics and subunit vaccines. The bulk production of flagellin with retention of all conformational epitopes using recombinant protein technology is of paramount importance in the development of pathogen-specific immuno-assays and vaccines. We describe the production of highly soluble and immuno-reactive rFliA(C) protein of Clostridium chauvoei, a causative agent of blackleg or black quarter (BQ) affecting cattle and small ruminants worldwide. The bacterium is known to possess peritrichous flagella that provide motility and also act as a virulence factor with high protective antigenicity. MethodsUpon sequence and structural analysis, a partial fliA(C) gene from Clostridium chauvoei was cloned and the recombinant mature protein with N- and C- terminal truncation was over-expressed as a His-tagged fusion protein (∼25 kDa) in Escherichia coli. Subsequently, rFliA(C) protein was purified by single-step affinity chromatography and characterized for its immuno-reactivity in laboratory animals, Western blot, and indirect-ELISA format. ResultsrFliA(C) was highly soluble and was purified in high quantity and quality. rFliA(C) elicited antigen-specific conformational polyclonal antibodies in rabbit and guinea pig models, as well as anti-Clostridium chauvoei-specific antibodies being specifically detected in BQ-vaccinated and convalescent sera of bovines in Western blot and in indirect-ELISA format. Further, no cross reactivity was noted with antibodies against major bovine diseases (e.g., foot-and-mouth disease, IBR, LSDV, hemorrhagic septicaemia, brucellosis, and leptospirosis). ConclusionThe study indicated the production of conformational recombinant flagellin—rFliA(C)—antigen and its potential utility in development of diagnostics for detection of Clostridium chauvoei-specific antibodies in BQ-recovered and/or vaccinated animals.

KCNE4 is a crucial host factor for Orf virus infection by mediating viral entry

The orf virus (ORFV) poses a serious threat to the health of domestic small ruminants (i.e., sheep and goats) and humans on a global scale, causing around $150 million in annual losses to livestock industry. However, the host factors involved in ORFV infection and replication are still elusive. In this study, we compared the RNA-seq profiles of ORFV-infected or non-infected sheep testicular interstitial cells (STICs) and identified a novel host gene, potassium voltage-gated channel subfamily E member 4 (KCNE4), as a key host factor involved in the ORFV infection. Both RNA-seq data and RT-qPCR assay revealed a significant increase in the expression of KCNE4 in the infected STICs from 9 to 48 h post infection (hpi). On the other hand, the RT-qPCR assay detected a decrease in ORFV copy number in both the STICs transfected by KCNE4 siRNA and the KCNE4 knockout (KO) HeLa cells after the ORFV infection, together with a reduced fluorescence ratio of ORFV-GFP in the KO HeLa cells at 24 hpi, indicating KCNE4 to be critical for the ORFV infection. Furthermore, the attachment and internalization assays showed decreased ORFV attachment, internalization, replication, and release by the KO HeLa cells, demonstrating a potential inhibition of ORFV entry into the cells by KCNE4. Pretreatment with the KCNE4 inhibitors such as quinidine and fluoxetine significantly repressed the ORFV infection. All our findings reveal KCNE4 as a novel host regulator of the ORFV entry and replication, shedding new insight into the interactive mechanism of ORFV infection. The study also highlights the K+ channels as possible druggable targets to impede viral infection and disease.

Baculovirus expression and purification of virion core and envelope proteins of goatpox virus to evaluate their diagnostic potential.

Goatpox and sheeppox are highly contagious and economically important viral diseases of small ruminants. Due to the risk they pose to animal health, livestock production, and international trade, capripoxviruses are a considerable threat to the livestock economy. In this study, we expressed two core proteins (A4L and A12L) and one extracellular enveloped virion protein (A33R) of goatpox virus in a baculovirus expression vector system and evaluated their use as diagnostic antigens in ELISA. Full-length A4L, A12L, and A33R genes of the GTPV Uttarkashi strain were amplified, cloned into the pFastBac HT A donor vector, and introduced into DH10Bac cells containing a baculovirus shuttle vector plasmid to generate recombinant bacmids. The recombinant baculoviruses were produced in Sf-21 cells by transfection, and proteins were expressed in TN5 insect cells. The recombinant proteins were analysed by SDS-PAGE and confirmed by western blot, with expected sizes of ~30 kDa, ~31 kDa, and ~32 kDa for A4L, A12L, and A33R, respectively. The recombinant proteins were purified, and the immunoreactivity of the purified proteins was confirmed by western blot using anti-GTPV serum. The antigenic specificity of the expressed proteins as diagnostic antigens was evaluated by testing their reactivity with infected, vaccinated, and negative GTPV/SPPV serum in indirect ELISA, and the A33R-based indirect ELISA was optimized. The diagnostic sensitivity and specificity of the A33R-based indirect ELISA were found to be of 89% and 94% for goats and 98% and 91%, for sheep, respectively. No cross-reactivity was observed with other related viruses. The recombinant-A33R-based indirect ELISA developed in the present study shows that it has potential for the detection of antibodies in GTPV and SPPV infected/vaccinated animals.

Epidemiological and pathomorphologic investigation of peste des petits ruminants in Western Algeria: A comprehensive study of clinical and histopathological findings.

This study delves into the epidemiology and pathomorphologic characteristics of peste des petits ruminants (PPR) in western Algeria, a viral disease that constantly threatens small animals in Africa, the Middle East, and Asia. The purpose of this investigation was to evaluate the epidemiology of PPR in western Algeria and to understand the pathomorphological lesions in naturally infected small ruminants. An online survey conducted via google forms and shared with veterinarians in the wilaya of Tiaret, provided insights into the prevalence and clinical manifestations of PPR.A comprehensive examination of organs was conducted and representative tissue samples from the lungs, trachea, thymus, spleen, liver, kidney, heart, tongue, stomach, different parts of the small and large intestine, and mesenteric lymph nodes were collected and the specimen was fixed in a 10% neutral buffer formalin solution. Among 2,200 small ruminants managed by expert veterinarians, 192 small ruminants exhibited clinical signs compatible with PPR, and 79 dead animals. Among the 31 sick young small ruminants, eight were confirmed to be infected with the PPR virus. Necropsies of affected animals revealed significant gross lesions in organs such as the lungs, intestines, spleen, and lymph nodes. Histopathological analysis further illuminated the severity of lesions, including interstitial pneumonia, syncytial cell formation, and severe gastroenteritis. The study's comprehensive approach, encompassing epidemiological data, necropsy findings, and histopathological insights, contributes valuable knowledge for understanding and managing PPR outbreaks.The pathological lesions observed in this study exhibited consistency with those previously documented in experimental studies, thereby providing support for the diagnosis based on clinical signs and disease history.

Prevalence of Toxoplasma gondii Infections in Pregnant Women and Small Ruminants: A Molecular Diagnostic Approach

Background: Toxoplasma gondii is a globally prevalent parasite with significant health implications, particularly for pregnant women and immunocompromised individuals. Infections during pregnancy can result in serious outcomes such as miscarriage, stillbirth, or congenital disabilities. This study aimed to assess the prevalence of T. gondii infection among pregnant women and small ruminants in Al-Anbar province, Iraq, using serological and molecular diagnostic techniques. Methods: Blood samples were collected from 165 pregnant women and 100 small ruminants (sheep and goats) between January and May 2021. Serological screening was conducted using the Humatex-Toxo rapid test to detect antibodies against T. gondii. DNA was extracted from the blood samples, and nested polymerase chain reaction (PCR) targeting the T. gondii B1 gene was used for molecular detection. The infection rates were analyzed statistically using ANOVA and Chi-square tests, with significance set at p<0.05. Results: The serological test identified T. gondii antibodies in 32.7% of pregnant women, while the PCR detected a higher infection rate of 40%. Among the small ruminants, PCR revealed an overall infection rate of 10%, with sheep showing a higher rate (16%) compared to goats (4%). The results indicate that PCR is more sensitive than serological testing, particularly for identifying active infections. Additionally, the higher infection rate in young women may be linked to lifestyle, environmental exposure, and dietary habits, while seasonal factors likely play a role in infection distribution. Conclusion: Nested PCR is a more effective method for detecting T. gondii in pregnant women, offering a precise tool for identifying infections and potential causes of abortion. The lower infection rates in small ruminants suggest a reduced zoonotic risk in the study area, although continued monitoring is essential. Negative PCR results may be due to inhibitors in the DNA extraction process or the parasite’s localization in tissues rather than blood. The findings highlight the importance of molecular diagnostics in public health strategies aimed at reducing T. gondii infections in high-risk populations.

Exploratory study for implementing a Global Burden of Animal Diseases case study in Senegal.

Senegal is a West African country with both extensive animal production systems, representative of the environmental, economic and animal health constraints specific to the Sahel region, and thriving commercial poultry and dairy production. An exploratory study was conducted in Senegal between 2021 and 2022 as a prelude to a case study of the Global Burden of Animal Diseases (GBADs) programme. An overview of existing animal production systems as well as the main priorities and issues in animal health on a national level was developed. A national workshop gathering representatives from the livestock production and academic sectors took place in Dakar in June 2022 with the objective of jointly developing a case study. The participants prioritised pastoralist production systems for cattle and agropastoral systems for small ruminants for the application of the GBADs programme. Through a series of activities, the participants highlighted the health, environmental, economic and socio-political challenges surrounding these systems, all of which limit their contribution to the well-being of pastoralist households, consumers and other stakeholders. While Senegal has in the past hosted a large number of research and cooperative projects on these two livestock systems, participants noted difficulties in obtaining, centralising and harmonising the existing data. This exploratory study led to the funding of a focused case study of the agropastoral small-ruminant sector that was carried out in 2023 in partnership with national and international organisations.

A methodological framework for attributing the burden of animal disease to specific causes.

The Global Burden of Animal Diseases provides an analytical framework to measure the overall health of various farmed animal populations, to estimate the farm-level burden of different diseases, incorporating production losses due to morbidity and mortality as well as health expenditure, and to identify the wider economic and human health impacts of animal disease. Attributing the burden of animal diseases to specific causes or groups of causes requires methodological choices, including the classification of diseases and the resulting health states that manifest in loss of production. The aim of this article is to address the key challenges in the process of estimating farm-level disease burden, including ambiguity in terminology, data availability and collation, and adjustments for comorbidity. Using infection with zoonotic Brucella spp. in small ruminants as an aetiological cause of disease and abortion as a sequela of multiple diseases, practical examples of the framework are provided. Cause-specific attribution of the burden of animal disease captures temporal and spatial trends, an understanding of which is essential for planning, monitoring and evaluating animal health programmes and disease interventions.

Cost-benefit analysis of intervention reducing young stock mortality in Ethiopia.

Livestock provide meat, milk, draught labour, are used for breeding, and act as a store of value for smallholder farmers. High young stock mortality (YSM) has the potential to cause significant financial loss. The Young Stock Mortality Reduction Consortium collaborated on a project to deliver a package of basic health and husbandry interventions to reduce YSM for cattle and small ruminants in mixed and pastoral production systems in Ethiopia. Prior to the intervention, YSM rates ranged from 9.8% for calves in mixed systems, to 35.6% for small ruminants in pastoral systems. Proportional reductions YSM from the intervention ranged from 60% for calves and for small ruminants in mixed systems, to 72% for calves in pastoral systems. This brief research report assesses the costs and benefits of the intervention ex-poste to determine its efficiency. NPVs for the intervention (per household) were calculated for a range of benefit periods (from 1 to 20 years), based on the cost of training enumerators and farmers and the net annual household benefits realised within each benefit period. We found in both pastoral and mixed systems the net annual household benefit for the intervention was positive. For pastoral households the intervention achieves a positive NPV after 2 years. For mixed households the intervention achieves a positive NPV after 11 years. Overall, we found the benefits of the intervention exceed the costs, by a very large amount in pastoral systems, and that benefits were larger for households that kept larger numbers of breeding females.

Distribution and molecular analysis of Subtilase cytotoxin gene (subAB) variants in Shiga toxin-producing Escherichia coli (STEC) isolated from different sources in Iran.

Subtilase exhibits strong cytotoxicity that was first described in O113:H21 strain in Australia as a plasmid- encoded cytotoxin (subAB1). Subsequently, chromosomal variants including subAB2-1, subAB2-2, and subAB2-3 were described. We aimed to investigate the presence of subAB genes in a collection of Shiga toxin-producing Escherichia coli (STEC) strains (n=101) isolated from different sources in Iran. A collection of 101 archived STEC strains isolated from cattle (n=50), goats (n=25), sheep (n=15), wild captive animals (n=8: persian fallow deer, n=3; caspian pony, n=1; Macaca mulatta, n=4), and humans (n=3) during 2007-2016 were analyzed for the detection of different genes encoding the Subtilase variants, plasmidic and chromosomal virulence genes, phylogroups and serogroups. Overall, 57 isolates (56.4%) carried at least one variant of subAB. Most strains from small ruminants including 93% of sheep and 96% of caprine isolates carried at least one chromosomally encoded variant (subAB-2-1 and/or subAb2-2). In contrast, 12 cattle isolates (24%) only harbored the plasmid encoded variant (subAB1). STEC strains from other sources, including deer, pony and humans were positive for subAB-2-1 and/or subAb2-2. Our results reveal the presence of potentially pathogenic genotypes among locus of enterocyte effacement (LEE)-negative isolates, and some host specificity related to Subtilase variants and other virulence markers that may aid in source tracking of STEC during outbreak investigations.

Molecular serogrouping and virulence of Listeria monocytogenes from sheep and goat milk in Jordan

Listeria monocytogenes is a serious pathogen with several serogroups that differ in virulence and distribution among countries. This study determined the serogroups and virulence of 116 L. monocytogenes from sheep milk (n = 52) and goat milk (n = 64) in Jordan by several multiplex PCR. The results showed that the L. monocytogenes isolates belong to five serogroups. Most isolates (37.9%) belonged to serogroup 4b (d, e), followed by serogroup 1/2a (3a) (31.9%), serogroup 1/2b (26.7%), and serogroup 4a/c (2.6%) and serogroup IV (serotypes 1/2c and 3c) (0.9%). All isolates carried the internalin (inlA, inlC, inlJ) and lmo 2672 genes. Additionally, 36.4% and 29.0 % of 4b and 1/2b isolates carried the Listeriolysin S gene (llsX). Therefore, L. monocytogenes in sheep and goat milk are potential public health hazards because they belong to the major listeriosis-causing serogroups (4b, 1/2a, and 1/2b), and carry major virulence genes. Small ruminants’ milk and cheeses should be considered high-risk foods for L. monocytogenes infection. Thus, safe production practices should be monitored and enforced in small dairy shops.

Livestock-associated spatial risk factors for human salmonellosis and campylobacteriosis.

Most human infections with non-typhoid Salmonella (NTS) or Campylobacter are zoonotic in nature and acquired though consumption of contaminated food of mainly animal origin. However, individuals may also acquire salmonellosis or campylobacteriosis through non-foodborne transmission pathways, such as those mediated by the environment. This emphasizes the need to consider both direct and indirect exposure to livestock sources as a possible transmission route for NTS and Campylobacter. Therefore, this study aimed at assessing whether salmonellosis and campylobacteriosis incidence is spatially associated with exposure to livestock (i.e. small ruminants, dairy cows, veal calves, laying hens, broiler chickens and pigs) in the Netherlands for the years 2007-2019 and 2014-2019 respectively. Risk factors (population-weighted number of animals) and their population attributable fractions were determined using a Poisson regression model with a log-link function fitted using integrated nested Laplace approximation. The analyses were performed for different hexagonal sizes (90, 50, 25 and 10 km2) and accounted for geographical coverage of the diagnostic laboratory catchment areas. Moreover, serological data were used to look into the possible effects of acquired immunity due to repeated exposure to the pathogen through the environment that would potentially hinder the analyses based on the incidence of reported cases. A linear mixed-effects model was then fitted where the postal code areas were included as a random effect. Livestock was not consistently significantly associated with acquiring salmonellosis or campylobacteriosis in the Netherlands. Results showed that living in livestock-rich areas in the Netherlands is not a consistently significant, spatially restricted risk factor for acquiring salmonellosis or campylobacteriosis, thereby supporting current knowledge that human infections with Salmonella and Campylobacter are mainly foodborne.

An 8000 years old genome reveals the Neolithic origin of the zoonosis Brucella melitensis

Brucella melitensis is a major livestock bacterial pathogen and zoonosis, causing disease and infection-related abortions in small ruminants and humans. A considerable burden to animal-based economies today, the presence of Brucella in Neolithic pastoral communities has been hypothesised but we lack direct genomic evidence thus far. We report a 3.45X B. melitensis genome preserved in an ~8000 year old sheep specimen from Menteşe Höyük, Northwest Türkiye, demonstrating that the pathogen had evolved and was circulating in Neolithic livestock. The genome is basal with respect to all known B. melitensis and allows the calibration of the B. melitensis speciation time from the primarily cattle-infecting B. abortus to approximately 9800 years Before Present (BP), coinciding with a period of consolidation and dispersal of livestock economies. We use the basal genome to timestamp evolutionary events in B. melitensis, including pseudogenization events linked to erythritol response, the supposed determinant of the pathogen’s placental tropism in goats and sheep. Our data suggest that the development of herd management and multi-species livestock economies in the 11th–9th millennium BP drove speciation and host adaptation of this zoonotic pathogen.

On the fauna of parasites of the gastrointestinal tract of small ruminants in the mountainous zone of Armenia

The aim of the research is to study the parasitic invasion of small ruminants in the mountainous zone of Armenia during summer and autumn, in this case to determine the invasiveness of parasites of the digestive tract of sheep.The material was feces collected from sheep on pastures in the coastal zone of the Getik River during 2022. The work was carried out at the Scientific Centre of Zoology and Hydroecology, National Academy of Sciences, Republic of Armenia. The material researched also included mollusks and oribatid mites – intermediate hosts of biohelminths.As a result of the study of parasitic invasion of small ruminants in the mountain zone of Armenia, the taxonomic composition of parasites was determined. Helminths found in sheep belong to the classes Trematoda, Nematoda, and Cestoda, protozoa – to the class Protozoa.In the autumn season, representatives of seven genera of parasites of the gastrointestinal tract were found – Moniezia, Dicrocoelium, Fasciola, Nematodirus, Strongylus, Trichuris, Eimeria, while in the summer season, only representatives of five genera were found – Moniezia, Dicrocoelium, Nematodirus, Strongylus, Eimeria.As a result of these studies, it can be concluded that natural and climatic factors of the environment have a significant impact on the structure of the helminth complex of sheep in the mountain region of Armenia.All parasites found can have a detrimental effect on the sheep's body. However, the severity of the invasion in the samples taken is not at the level that could lead to serious diseases in sheep. This suggests that the treatment methods used on farms are at a fairly high level.

Detection and quantification of antibiotic residues in goat milk in Mahikeng Local Municipality.

Goat milk could be used to reduce malnutrition since it is highly nutritious, and many people in rural communities in South Africa rear small ruminants for survival. However, the risk of food contamination by antibiotic residues is one of the significant problems facing public health, and is a result of the irresponsible use of veterinary drugs. One hundred goat farmers were interviewed using a questionnaire, and raw milk samples from 266 goats were collected and analysed for the presence of antibiotic residues. Screening for amoxicillin, tetracycline, sulfamethazine, erythromycin, and streptomycin residues was done using the enzymelinked immunosorbent assay (ELISA) while high-performance liquid chromatography (HPLC) was carried out for confirmation. The questionnaire shows that all (100%) of the participants acknowledged the use of antibiotics on their goats and 99% of them were aware of the possibility of antibiotic residues in milk. ELISA results for residues of erythromycin, sulfamethazine and amoxicillin exceeded the Codex Alimentarius maximum residue levels (MRLs) in 94.7%, 82.3%, and 35.3% of analysed samples, respectively. Tetracycline was present in all (100%) analysed milk samples, and streptomycin was detected in 18.7% of samples; however, these results were below the recommended MRLs. The HPLC method confirmed the presence of streptomycin and tetracycline residues in 90% and 40% of the samples analysed. However, the concentrations were below the accepted MRL standards. Approximately 76.6% of samples exceeded the established MRL for sulfamethazine and 10% for erythromycin. Amoxicillin was not detected by the HPLC method. The results obtained in this study indicate a high level of contamination of goat milk with antibiotic residues, which may harm the health of the consumers.

Characterization of the ruminal microbiota in sheep and goats fed different levels of tannin-rich Sericea lespedeza hay.

Understanding ruminal microbiota and diet-host breed interactions under forage feeding conditions is essential for optimizing rumen fermentation and improving feed efficiency in small ruminants. This study aimed to investigate the effects of different ratios of condensed tannin-rich Sericea lespedeza (SL; Lespedeza cuneata) in the diets on changes and interactions of ruminal microbiota and host species (i.e., sheep and goats). Katahdin sheep (n = 12) and Alpine goats (n = 12) at approximately 10 to 12 mo of age were blocked by body weight (BW = 30.3 and 25.5kg, respectively) and randomly assigned to one of the 3 treatments. Diets contained 75% coarsely ground forage and 25% concentrate. The forages were 1) 100% alfalfa hay (AL), 2) 100% SL, and 3) 50% AL + 50% SL (ASL). In the present study, the diversity and composition of ruminal microbiota differed between sheep and goats fed similar diets. Based on the taxonomic analysis, there was a distinct clustering pattern (P < 0.05) for sheep by diets, but such a pattern was not observed for goats (P > 0.1). The most predominant phyla were Firmicutes, Bacteroidetes, Ascomycota, and methanogen species of Methanobrevibactor sp. in the rumen of sheep and goats, regardless of diets. The Bacteroidetes and Ascomycota were enriched in sheep fed AL and ASL. In contrast, these microbial phyla were enhanced in goats fed tannin-rich SL diets, with the diet-by-host species interaction (P < 0.02) for the Bacteroidetes phylum. Sheep rumen fluid samples showed a higher degree of variability in microbial community composition compared to goat rumen fluid samples. The relative proportion of the Aspergillus fungi population was reduced to 90.7% in the SL group compared with the AL group, regardless of host species. The antimicrobial activity of tannins and greater sensitivities of selected microbiota species to these tannin compounds during SL feeding in sheep and goats perhaps caused this difference. The results from this study suggest that differences in the microbiota were associated with differences in diets and host species. Therefore, this study provides a better understanding of ruminal microbiota and diet-host species interactions under various tannin-rich diets, which could advance consolidative information on rumen microbiome community diversity changes and may improve sheep and goat production.

Molecular prevalence and distribution of tick-borne bacterial and protozoan pathogens of sheep and goats in Africa: A systematic review and meta-analysis

Tick-borne pathogens (TBPs) are a major impediment to the health, welfare, and production of small ruminants across the world, including Africa. Comprehensive information about the epidemiology of TBPs infecting sheep and goats across Africa is lacking. Therefore, this study was undertaken to determine the prevalence through a meta-analysis of selected TBPs in blood DNA from domestic sheep and goats in Africa obtained using molecular-based methods. The literature review was done according to Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) guidelines using five English electronic databases (PubMed, Science Direct, Springer Link, Web of Science, and African Journals Online (AJOL). The search was performed with no restriction in time through to 18th January 2023. Of the 63 full-text articles subjected to eligibility, only 30 articles met the eligibility criteria and were included in the review. The overall pooled prevalence of selected TBPs varied considerably between host species (sheep vs. goats), with Anaplasma ovis (44.50 vs. 48.40%), Ehrlichia ruminantium (5.50 vs. 2.00%), Coxiella burnetii (4.40 vs. 1.70%), Borrelia theileri in sheep (5.20%), Babesia ovis (1.70% vs. 1.90%), Theileria ovis (40.50% vs 10.00%), T. separata (1.00% vs 1.00%) and T. lestoquardi in sheep (8.40%). However, the prevalence of the selected TBPs was generally higher in sheep compared to goats. Several genetic loci were targeted in the characterization of tick-borne pathogens, such as 16S rDNA, groEL, and msp4 for Anaplasma ovis, pCS20 for Ehrlichia ruminantium, Insertion Sequence (IS1111) for Coxiella burnetii, flaB (flagellin) and 16S rRNA for Borrelia theileri, 5.8S rRNA and 18S rRNA for Babesia/Theileria, as well as the utilization of numerous PCR variants including conventional polymerase chain reaction (PCR), nested-PCR, qPCR, Loop-mediated isothermal amplification (LAMP), and reverse line blotting (RLB). In conclusion, A. ovis was the most widely distributed and prevalent TBP affecting small ruminants within the continent. Hence, this warrants adequate attention towards early diagnosis and treatment of infected animals as well as the control of the tick vectors involved in their transmission.

Lecanicillium psalliotae (Hypocreales: Cordycipitaceae) Exerts Ovicidal and Larvicidal Effects against the Sheep Blood-Feeding Nematode Haemonchus contortus through Its Liquid Culture Filtrates.

Nematophagous fungi (NF) form part of the soil microbiota and are natural enemies of nematodes, helping to regulate nematode populations. A verticillate NF isolated from soil from Tepalcingo, Mexico, was morphologically and molecularly characterised. This fungus was cultured in two different liquid media-Czapek-Dox broth (CzDoxB) and sweet potato dextrose broth (SPDB)-for 21 days. The ovicidal (OA) and larvicidal (LA) activities of fungal liquid culture filtrates (LCFs) were assessed in 96-well microtitre plates at different concentrations against Haemonchus contortus after 48 h. The morphological and molecular identification revealed the presence of Lecanicillium psalliotae. Additionally, the groups of compounds associated with nematocidal activity were determined from a qualitative chemical profile (QCP) using different reagents. The highest OA of the LCFs was obtained at 25 mg/mL from SPDB and CzDoxB and amounted to 97.2 and 99.06%, respectively. Meanwhile, the highest LA recorded with these LCFs at 100 mg/mL was 54.27% and 96.8%, respectively. The QCP revealed the presence of alkaloids and tannins in both LCFs that have previously been associated with nematocidal activity. Lecanicillium psalliotae exerted an important effect on H. contortus and could be of significance in future studies focused on the control and prevention of haemonchosis in small ruminants.

Seroprevalence of Coxiella burnetii and potential tick vectors infesting domestic ruminants and community perception of the disease in pastoral areas of south Omo zone, southern Ethiopia

BackgroundQ fever is a worldwide occurring neglected zoonotic disease with great economic importance. The etiological agent, Coxiella burnetii, is a bacterium usually associated with subclinical infections in livestock, but may also cause reproductive pathology and spontaneous abortions in artiodactyl species including goats, sheep and cattle which are deemed to be the primary reservoirs of this disease. AimsThe present cross-sectional and questionnaire survey was undertaken in three districts of the South Omo zone with the aims to comprehend the community perception of livestock keepers and professionals about the disease, estimate the seroprevalence of Coxiella burnetii (C. burnetii) in cattle and small ruminants and to determine the species of potential tick vectors of C. burnetii infesting cattle, sheep and goats. MethodsA standard questionnaire was used to assess the community perception of livestock keepers and animal health professionals in the area about Q fever. Sera samples were collected from 1350 ruminants comprising 450 cattle, 450 goats and 450 sheep to detect C. burnetii antibodies using the ELISA technique. Furthermore, a total of 279 cattle, 197 goats and 73 sheep were examined for the presence of ticks, and overall, 2720 ticks were collected (1299 from cattle, 1020 from goats and 401 from sheep) and identified to the species level using morphologically identification keys. ResultsFindings of the study indicated that 43% of animal owners were aware of the main symptoms of the disease while the remaining 57% did not notice these symptoms in their animals. Additionally, majority of animal health professionals 76.2% in the area reported they were familiar with the causative agent of Q fever, while 23.8% expressed uncertainty regarding the cause of coxiellosis. An overall seroprevalence of C. burnetii of 37.6% in cattle (37.4% in female and 37.8% in male cattle) and 28.7% in small ruminants was recorded (which is significantly higher in goats than in sheep). The study indicated statistically significantly higher seroprevalence of C. burnetii (49.8%) in cattle infested with ticks than in those cattle free of ticks (24.2%), with three times higher seropositivity (OR = 2.97, p = 0.000) as compared to those cattle free of ticks (24.2%). Similarly, statistically significantly higher seroprevalence of C. burnetii was recorded in both sheep and goats infested with ticks (43.6%) as compared to those animals without ticks (22.9%), with the former being twice as likely to test seropositive (OR = 2.15, p = 0.000). A total of nine different tick species were identified, namely Amblyomma variegatum (Am. variegatum) with 26.3% (342; 217 males, 101 females and 24 nymphs), Amblyomma cohaerens (Am. cohaerens) with 47.96% (370 males, 253 females), Amblyomma gemma (Am. gemma) with 4.00% (52; 29 males, 23 female), Rhipicephalus pulchellus (Rh. pulchellus) with 10.6% (138; 87 males, 51 females), Rhipicephalus pravus (Rh. pravus) with 0.2% (3; 2 males, 1 females), Rhipicephalus evertsi (Rh. evertsi) with 4.7% (61; 39 males, 22 females), Rhipicephalus praetextatus (Rh. praetextatus) with 0.8% (10; 7 males, 3 females), Rhipicephalus decoloratus (Rh decoloratus) with 2.9% (38; 4 males, 34 females) and Hyalomma truncatum (Hy. truncatum) with 2.5% (32 females). ConclusionThe present study highlighted the significance of Q fever in ruminants and compiled information about the community perception of livestock keepers and veterinary professionals of the study areas. The role of ruminants and their ticks in the epidemiology of C. burnetii requires further research using molecular tools to better understand appropriate method of intervention that will help to reduce negative impacts on the productivities of livestock and the health of humans in Ethiopia.