Abstract Background: Rift Valley fever (RVF) is a zoonotic viral disease transmitted by mosquitoes, that causes significant impacts on animal health, public health, and socio-economic wellbeing in affected areas. Although RVF vaccines for livestock are available and human vaccines are currently under development, a coordinated One Health approach to vaccination has yet to be fully explored. This mini-review article aims to examine RVF vaccination strategies from a One Health perspective. Methods: Through a narrative literature review, evidence on RVF vaccination strategies for animals and humans was analyzed. Recurring themes relevant to decision making were identified and categorized into six interconnected decision domains, establishing a “One Health vaccination strategies” (OHVS) framework used to structure the synthesis and discussion of the evidence. Based on the available literature, as well as on strategies implemented for livestock and mathematical modeling studies, six joint scenarios combining livestock and human vaccination are suggested for future investigations. Results: Current evidence primarily supports preventive mass vaccination for livestock and indicates a targeted strategy for high-risk human populations. Conclusions: The expected synergistic benefits for affected communities, along with the balanced distribution of responsibilities and resources across sectors, make OHVS a valuable intervention framework. Once RVF human vaccines become available, this unified approach can strengthen collaboration among public health, veterinary, and environmental sectors, leading to a more effective, equitable, and sustainable intervention landscape. One Health impact statement Rift Valley fever (RVF) exemplifies the intricacies of environmental, human, and animal interconnections and interdependencies. Countries such as Tanzania where RVF is endemic have experienced decadal outbreaks in addition to a potential persistent transmission pattern, warranting implementation of vaccination programs that are effective in the context of complex disease ecosystem. This article explores the possibilities for vaccinating animals and humans as a critical component of a unified One Health approach to RVF prevention and control, drawing from existing literature and promising new research paths. It also outlines a practical decision making framework to help shape effective RVF vaccination strategies for both human and animal populations. By working closely with partners in Tanzania and the United States, this initiative demonstrates proof of concept for the importance of transdisciplinary collaboration and cross-sectoral coordination in disease prevention and control. This also provides actionable insights for both the scientific community and decision makers.

Crimean-Congo hemorrhagic fever virus (CCHFV) is a tick-borne zoonotic pathogen widely distributed across Africa, Asia, and Europe. Human infection occurs through tick bites or contact with infected animal tissues. In Tanzania, evidence of human exposure exists, but data on population-level seroprevalence and associated behavioral risk factors remain limited. This study assessed human CCHFV seroprevalence and identified demographic, behavioral, and environmental factors associated with prior exposure in livestock-keeping communities in southcentral Tanzania. A community-based cross-sectional study was conducted in four districts of southcentral Tanzania during 2023–2024. A total of 850 adults completed structured questionnaires on demographic and behavioral factors and provided blood samples. Serum samples were tested for CCHFV IgG antibodies using a commercial ELISA. Logistic regression models were used to identify factors associated with seropositivity. Overall CCHFV seroprevalence was 3.41

The loss in number and function of wet meadow ecosystems in California is often associated with reduced drought tolerance and impaired water quality in watersheds. This research focused on investigating the improvement of meadow health and water quality by implementing best management practices (BMPs), particularly wildlife-friendly, cattle-exclusion fencing (allowing passage of wildlife) along streams, in a multi-use riparian wet meadow system. This longitudinal study followed the concentration of fecal indicator bacteria and fecal pathogens in the stream water from 2017 through 2022. Total coliforms, Escherichia coli, Giardia cysts, Cryptosporidium oocysts, and hydrologic parameters were monitored. The impact of the cattle exclusion fencing was evaluated using mixed-effect negative binomial and logistic regression models. Using EPA Method 1623, the overall prevalence of exceeding water quality standards for E. coli, Giardia spp., and Cryptosporidium spp. in the stream surface waters was 12.9%, 17.7%, and 27.1%, respectively. When the cattle exclusion fencing was present in a downstream location, E. coli in stream samples was reduced by 28 organisms/100 ml . Furthermore, significantly fewer water samples exceeded the regulatory thresholds set by the California State Water Resources Control Board when exclusion fencing was present. No statistically significant association was detected between fencing and the presence of Giardia spp. or Cryptosporidium spp. The hydrologic data revealed that the valley floor held more water over time, which was released more slowly throughout the year. This indicates that the wet meadow function is recovering, and suggests that using BMPs, including wildlife-friendly cattle exclusion fencing, in a multi-use wet meadow ecosystem that includes ranching, can help improve surface water quality and ecosystem health.

Rift Valley fever (RVF) is a re-emerging vector-borne zoonotic disease that causes outbreaks in humans and animals across Africa. To better understand RVF at human–animal interfaces, a prospective longitudinal survey of people, livestock, and mosquitoes was conducted from 2016 to 2018, in two regions of Tanzania, with distinct climatic zones (Iringa and Morogoro). Molecular and serological tools for testing (RT-qPCR and IgM/IgG ELISA) for RVF virus (RVFV) were used to assess infection and exposure in people and animals. Mosquitoes were collected quarterly from 10 sentinel locations. In total, 1385 acutely febrile humans, 4449 livestock, and 3463 mosquito pools were tested. In humans, IgM seroprevalence was 3.75% (n = 52/1385), and overall seroprevalence (IgM and/or IgG positive) was 8.30% (n = 115/1385). People from Iringa had a higher exposure risk than those from Morogoro (aOR 2.63), and livestock owners had an increased risk compared to non-owners (aOR 2.51). In livestock, IgM seroprevalence was 1.09%, while overall seroprevalence was 10.11%. A total of 68.4% of herds had at least one seropositive animal. Sentinel animal follow-up revealed that the probability of seroconversion was significantly higher in Morogoro. Low-level RVFV RNA was detected in 8 human and 22 mosquito pools. These findings indicate active transmission among vectors, livestock, and people during the study period, highlighting the need for One Health surveillance approaches for RVFV and other arboviruses.

Challenges in livestock production in developing countries are often linked to a high disease prevalence and may be related to poor husbandry, feeding, and nutrition practices, as well as to inadequate access to preventive veterinary care. Structural barriers including chronic poverty, gender roles, inadequate supply chains, and limitations in surveillance infrastructure further complicate progress. Despite many challenges, the livestock sector substantially contributes to agricultural GDP, and reducing livestock disease prevalence is a goal for many countries. One Health initiatives that work across disciplines and sectors to reduce livestock diseases are underway around the world and use integrated approaches that consider the connections between humans, animals, and their shared environments. The growing recognition of the role livestock play in sustainability and livelihoods, as well as their involvement in zoonotic disease transmission and global health security, has highlighted the need for disease reduction strategies as described in this review.

In 2010, USAID catalyzed the formation of One Health University Networks as part of a holistic response designed to promote the One Health approach for addressing complex health challenges. This globally connected One Health University network now includes the African One Health University Network (AFROHUN) and the Southeast Asia University Network (SEAOHUN) and has representation from over 120 universities in 17 countries across Africa and Southeast Asia. Over more than 15 years of USAID investment, these networks have trained more than 85,000 students, in-service professionals and faculty around the world in One Health principles and collaborative problem solving, grounded in One Health core competencies. These One Health practitioners have gone on to contribute to improved global health security in their communities and countries. The evolution and maturation of these networks is a testament to a strong vision and dedication to the task by leadership and donors. As the global academic community continues to refine and adapt training methodologies for ‘future ready’ individuals, resources and examples from One Health University Networks stand as a legacy to build upon.

ABSTRACT Antimicrobial resistance in Vibrio species poses risks to both human and marine mammal health. Whole genome sequencing of Vibrio spp. can be utilized to screen for antimicrobial resistance genes and allelic variants to provide mechanistic insights in ways that PCR screening and phenotypic interpretation cannot. Our goals were to (i) characterize antimicrobial resistance patterns of Vibrio spp. pathogens isolated from southern sea otters ( Enhydra lutris nereis ), northern sea otters ( Enhydra lutris kenyoni ), and environmental samples from the central California coast using whole genome sequencing, and (ii) compare the presence of antimicrobial resistance genes with phenotypic interpretation from antibiotic susceptibility testing. Unexpectedly, genomic classification identified an understudied species, Vibrio diabolicus , in sea otter and environmental isolates that were previously identified as Vibrio alginolyticus . A total of 489 Vibrio spp. isolates were sequenced, and frequently detected antimicrobial resistance genes included multidrug efflux pumps and genes associated with resistance to ß-lactams and tetracyclines. Genes associated with resistance to fluoroquinolones, aminoglycosides, chloramphenicol, and sulfonamides were uncommon. Sea otter isolates were phenotypically susceptible to tetracycline despite carrying genes tet34 and tet35 . Both between- and within-species variations in ampicillin resistance were observed despite the ubiquitous presence of bla CARB genes in V. alginolyticus , V. diabolicus , and Vibrio parahaemolyticus . Discordance between phenotypic and genotypic ampicillin resistance was especially noted for V. parahaemolyticus and was partially attributed to the allelic variation of the bla CARB genes. Tetracyclines and fluoroquinolones, but not ß-lactams, are likely to be effective treatments for vibriosis in sea otters. IMPORTANCE Vibriosis (infection with non-cholera Vibrio spp.) is the most common seafood-borne illness globally, with major impacts on public health, food security, and wildlife health. Potential treatments of antimicrobial-resistant Vibrio spp. in humans, aquaculture, and marine wildlife rehabilitation are complicated by current diagnostic challenges regarding bacterial species identification and interpretation of antimicrobial resistance patterns. Unexpected detection of previously misidentified Vibrio diabolicus in sea otters suggests that a broader taxonomic group of Vibrio infect sea otters than previously described. We also determined that the presence of ß-lactamase genes alone in sea otter isolates does not necessarily correlate with an ampicillin-resistant phenotype, likely due to deleterious amino acid substitutions in certain bla CARB alleles. Continued monitoring of Vibrio spp. phenotypes and genotypes in sea otters is warranted to observe biologically relevant changes in antimicrobial resistance.

AbstractBackgroundEvaluating antibody titers for Sarcocystis neurona for the diagnosis of equine protozoal myeloencephalitis from serum samples is a common practice. However, ensuring timely and proper refrigeration is not always possible.ObjectivesTo evaluate immunofluorescent antibody (IFA) titers for S. neurona from serum samples stored at room temperature and 4°C.SamplesTwenty‐two serum samples.MethodsProspective longitudinal study. Two serum aliquots of 1 mL each were stored at room temperature (20‐23.3°C) and 4°C. The unrefrigerated aliquot was immediately tested for IFA titers. Both aliquots were retested on Days 5 and 10 after collection. A paired t test was used to compare IFA titers at different time points.ResultsThere was no significant difference between IFA titers from baseline with those stored at room temperature at Days 5 (P = .741, 95% CI [−56.83, 78.65]), 10 (P = .677, 95% CI [−50.01, 75.46]), and between 5 and 10 days (P = 0.949, 95% CI [−57.50, 61.14]). There was no significant difference from baseline with those stored at 4°C for Days 5 (P = .964, 95% CI [−81.81, 85.45]), 10 (P = 0.573, 95% CI [−109.4, 62.15]), and between 5 and 10 days (P = .5, 95% CI [−102.6, 51.67]). There was no statistical difference between samples stored at room temperature and 4°C (P = .688, CI [−55.51, 37.33]) on Days 5 and 10 (P = .104, CI [−80.8, 8.07]).Conclusions and Clinical ImportanceImmunofluorescent antibody test titers for S. neurona are stable for up to 10 days at room temperature and 4°C.

ABSTRACT Installing beaver dam analogs (BDAs) in freshwater ecosystems is a process-based restoration technique mimicking natural beaver dams to increase stream channel complexity, floodplain connectivity, and hydrological residence time. BDAs have been applied in recent years by resource managers to improve riparian habitats with beneficial effects on ecosystem services, including improved water quality. While BDAs have been shown to reduce suspended sediments and nutrients in surface waters, research is needed to evaluate BDA effects on waterborne fecal pathogens such as Giardia duodenalis (syn. G. lamblia , G. intestinalis ) and Cryptosporidium parvum . At a California riparian field site, this study used an in situ release trial of inactivated protozoal (oo)cysts upstream of BDAs to compare the concentrations and loads detected above and below the BDAs. The median percent decrease in load-based recovery rates was 78% for G. duodenalis and 80% for C. parvum at sites with BDAs. Mixed-effect linear regression analyses showed a significant reduction (by 81%) of the G. duodenalis adjusted cyst concentrations in downstream surface waters at sites with BDAs compared to similar sites without BDAs. While a reduction of C. parvum oocysts was noted, it was not statistically significant. The improved surface water quality downstream of BDAs could be because the BDA structures promote hyporheic exchange and act as a passive filter to remove pathogenic protozoa from streams. If BDAs are used to aid the restoration of riparian meadow ecosystems to slow water and raise the water table, they may also help to promote cleaner and safer waters for communities downstream. IMPORTANCE Beaver dam analogs (BDAs) are a cost-effective, low-environmental impact technique for stream and riparian meadow restoration that provide a variety of beneficial ecosystem services; however, their impact on waterborne fecal protozoal pathogens has not been evaluated. This study used an in situ protozoal release trial to quantify the effect of BDAs on the load of Giardia duodenalis and Cryptosporidium parvum in streams in California. Results showed that G. duodenalis concentrations below BDAs were significantly reduced by 81%. The median percent decrease in load-based recovery rates below a BDA for G. duodenalis and C. parvum was 78% and 80%, respectively. This finding indicates that BDAs may promote passive filtration of waterborne pathogens, thereby improving water quality in downstream reaches and adding to the beneficial outcomes associated with using BDAs in stream and meadow restoration efforts. The potential benefit to resource managers and communities is immense.

Background: Between January 1, 2011, and December 31, 2017, over 12,000 case reports of Lyme disease (LD) were submitted to the California Reportable Disease Information Exchange for further investigation. The number of case reports has tripled compared to previous years, emphasizing the need for efficient estimation and classification methods. We evaluated whether estimation procedures can be implemented in a low-incidence state such as California to correctly classify a case of LD, similar to those procedures used in high-incidence states.Objective: The purpose of this study was to identify whether a minimum number of variables was sufficient to reliably classify cases in California and potentially reduce workload while maintaining the ability to track LD trends in California.Methods: To determine the relative value of diagnostic information, we compared five candidate logistic regression models that were used to classify cases based on information that varied in its degree of difficulty for collection.Results: Our results using California's surveillance data showed that automatically reported data were not sufficient, additional information such as, a patient's clinical presentation and travel history were necessary in a low-incidence state to improve the overall sensitivity of the models.Conclusion: This study may help inform public health surveillance efforts by demonstrating that both clinical and travel information are required to accurately classify a case of LD in a low-incidence state.

Equine protozoal myeloencephalitis (EPM) is a challenging disease to diagnose in horses with neurological signs. To optimize contemporary diagnostic testing, including the use of serum:CSF antibody ratios, the SarcoFluor antibody test for Sarcocystis neurona requires revalidation. The SarcoFluor, a previously validated immunofluorescent antibody test (IFAT) for the detection of antibodies specific to S. neurona in serum and cerebrospinal fluid (CSF) of naturally infected horses was analyzed using recent data and considering a serum:CSF antibody ratio threshold. Utilization of serum and CSF phosphorylated neurofilament heavy protein (pNfH) concentrations in support of an EPM diagnosis was also evaluated. 172 horses were divided into three groups: EPM-positive horses (EPM+, n=42), neurological non-EPM horses (n=74) confirmed with non-EPM neurological diseases (cervical vertebral compressive myelopathy, equine neuroaxonal dystrophy/equine degenerative myeloencephalopathy), and control horses (control, n=56) without neurological signs and neurological abnormalities on histology. Logistic regression was used to compare EPM diagnostic regimens. Specifically, EPM+ horses were compared with neurological non-EPM horses showing neurological signs. To consider diagnostic utility, post-test probabilities were calculated by titer. When differentiating between EPM and other neurological diseases, the combination of serum and CSF SarcoFluor testing added more information to the model accuracy than either test alone. Using serum and CSF for pNfH in support of an EPM diagnosis did not identify cutoffs with statistically significant odds ratios but increased the overall model accuracy when used with the IFAT. Utilization of IFAT titers against S. neurona in serum and CSF result in a high post-test probability of detecting EPM+ horses in a clinical setting.

Among the recognized neurologic diseases in horses, equine protozoal myeloencephalitis (EPM) has been reported around the world and still presents challenges in diagnosis and treatment. Horses can present with clinical neurologic signs consistent with EPM while testing negative for the two main causative agents, Sarcocystis neurona or Neospora hughesi, and may still be clinically responsive to anti-parasitic drug therapy. This context led to our hypothesis that another protozoal parasite, Toxoplasma gondii, which is known to cause toxoplasmosis in other mammalian species, is a potential pathogen to cause neurologic disease in horses. To evaluate this hypothesis, serum and cerebrospinal fluid (CSF) were collected from 210 horses presenting with clinical signs compatible with EPM, and the indirect immunofluorescent antibody test (IFAT) was used to detect antibody titers for T. gondii, S. neurona, and N. hughesi. Additionally, the serum to CSF titer ratio was calculated for T. gondii, S. neurona, and N. hughesi infections, suggesting intrathecally-derived antibodies for each of the three agents if the serum:CSF ratio was ≤ 64. There were 133 (63.3%) horses positive for serum T. gondii antibodies using a cutoff titer of 160, and 31 (14.8%) positive for CSF T. gondii antibodies using a cutoff titer of 5. Overall, 21 (10.0%) of EPM-suspect horses had a serum:CSF ratio ≤ 64 for antibodies for T. gondii, while 43 (20.5%) and 8 (3.8%) horses had a serum to CSF ratio ≤ 64 for antibodies for S. neurona and N. hughesi, respectively. A total of 6 (2.9%) animals presented evidence of concurrent intrathecally-derived antibodies for T. gondii and at least one other apicomplexan parasite in this study. Signalment and clinical signs were not different across the groups aforementioned. These data provide evidence of intrathecal production of anti-T. gondii antibodies, indicative of T. gondii infection in the brain and/or spinal cord of horses with EPM-like disease.

Background One Health is defined as an integrated, unifying approach that aims to sustainably balance and optimize the health of people, animals and ecosystems; this approach attracts stakeholders from multiple sectors, academic disciplines, and professional practices. The diversity of expertise and interest groups is frequently and simultaneously framed as ( 1 ) a strength of the One Health approach in the process of understanding and solving complex problems associated with health challenges such as pathogen spillovers and pandemics and ( 2 ) a challenge regarding consensus on essential functions of One Health and the sets of knowledge, skills, and perspectives unique to a workforce adopting this approach. Progress in developing competency-based training in One Health has revealed coverage of various topics across fundamental, technical, functional, and integrative domains. Ensuring that employers value the unique characteristics of personnel trained in One Health will likely require demonstration of its usefulness, accreditation, and continuing professional development. These needs led to the conceptual framework of a One Health Workforce Academy (OHWA) for use as a platform to deliver competency-based training and assessment for an accreditable credential in One Health and opportunities for continuing professional development. Methods To gather information about the desirability of an OHWA, we conducted a survey of One Health stakeholders. The IRB-approved research protocol used an online tool to collect individual responses to the survey questions. Potential respondents were recruited from partners of One Health University Networks in Africa and Southeast Asia and international respondents outside of these networks. Survey questions collected demographic information, measured existing or projected demand and the relative importance of One Health competencies, and determined the potential benefits and barriers of earning a credential. Respondents were not compensated for participation. Results Respondents ( N = 231) from 24 countries reported differences in their perspectives on the relative importance of competency domains of the One Health approach. More than 90% of the respondents would seek to acquire a competency-based certificate in One Health, and 60% of respondents expected that earning such a credential would be rewarded by employers. Among potential barriers, time and funding were the most cited. Conclusion This study showed strong support from potential stakeholders for a OHWA that hosts competency-based training with opportunities for certification and continuing professional development.

In Tasmania, Australian fur seals (Arctocephalus pusillus doriferus) regularly interact with Atlantic salmon (Salmo salmar L.) aquaculture lease operations and opportunistically consume fish. The microbial communities of seals and aquaculture salmon were analyzed for potential indicators of microbial sharing and to determine the potential effects of interactions on wild seal microbiome composition. The high-throughput sequencing of the V1–V3 region of the 16S rRNA genes from the gut microbial communities of 221 fur seals was performed: 41 males caught at farms, 50 adult scats from haul-outs near farms, 24 necropsied seals, and controls from Bass Strait breeding colonies, encompassing 56 adult scats and 50 pup swabs. QIIME2 and R Studio were used for analysis. Foraging at or near salmon farms significantly shifted seal microbiome biodiversity. Taxonomic analysis showed a greater divergence in Bacteroidota representatives in male seals captured at farms compared to all other groups. Pathogens were identified that could be monitoring targets. Potential indicator amplicon sequence variants were found across a variety of taxa and could be used as minimally invasive indicators for interactions at this interface. The diversity and taxonomic shifts in the microbial communities of seals indicate a need to further study this interface for broader ecological implications.

Morbidity and mortality of young stock is a challenge for livestock producers globally. In Ethiopia, where camels and small ruminants (sheep and goats) are essential smallholder and pastoral livestock, young stock losses can cause severe consequences to livelihoods.This pilot study, part of a Government-led Young Stock Mortality Reduction Consortium project, was undertaken to identify and evaluate interventions to reduce young stock mortality in mixed crop-livestock and pastoral production systems in Ethiopia. Pastoralists and mixed crop-livestock farmers were enrolled by con-venience sampling across four regions. Households were sampled with questionnaire surveys to establish base -line mortality risk and prevalence of diarrhoea and respiratory disease in animals younger than one year, and followed longitudinally over a one-year period, with final evaluations conducted from March to July 2020. Mortality risk and prevalence of diarrhoea and respiratory disease before and after implementation were compared using Poisson regression models including household as random effect.Prior to intervention, median camel mortality, prevalence of diarrhoea, and respiratory disease across pro-duction systems in the different households was 0.4, 0.44 and 0.2, respectively. This compared to median pastoralist small ruminant mortality risk and prevalence of diarrhoea and respiratory disease of 0.45, 0.32 and 0.18, respectively. Post-intervention, median camel mortality, prevalence of diarrhoea and respiratory disease dropped to 0.1, 0.08 and 0. Similarly, more than half of the small ruminant households reported no mortality, and no cases of diarrhoea or respiratory disease. In camels, rate ratios of mortality risk, prevalence of diarrhoea, and respiratory disease post-intervention compared to the baseline were 0.41, 0.41 and 0.37. In small ruminants, rate ratios were 0.33, 0.35 and 0.46. All reductions were statistically significant (p < 0.01). Generally, pastoralists experienced higher mortality and disease prevalence compared to mixed crop-livestock smallholders, and the effect of intervention was slightly higher in pastoralist households.The pilot study findings demonstrated highly significant reductions in mortality and risk of diarrhoea and respiratory disease post-interventions. However, not all households benefitted from the interventions, with a few households reporting increased mortality and morbidity. Many households had very few animals which made it challenging to measure impact and the study was conducted over a single year, without a control group, sobetween year effects could not be accounted for in the reductions observed. These findings should contribute to improved livestock productivity in Ethiopia.

Southern sea otters (SSO: Enhydra lutris nereis) are a federally-listed threatened subspecies found almost exclusively in California, USA. Despite their zoonotic potential and lack of host specificity, K. pneumoniae and Klebsiella spp. have largely unknown epizootiology in SSOs. Klebsiella pneumoniae is occasionally isolated at necropsy, but not from live SSOs. Hypermucoviscous (HMV) K. pneumoniae strains are confirmed pathogens of Pacific Basin pinnipeds, but have not been previously isolated from SSOs. We characterized the virulence profiles of K. pneumoniae isolates from necropsied SSOs, evaluated killing of marine mammal K. pneumoniae following in vitro exposure to California sea lion (CSL: Zalophanus californianus) whole blood and serum, and characterized lesion patterns associated with Klebsiella spp. infection in SSOs. Four of 15 SSO K. pneumoniae isolates were HMV and all were recovered from SSOs that stranded during 2005. Many K. pneumoniae infections were associated with moderate to severe pathology as a cause of death or sequela. All HMV infections were assessed as a primary cause of death or as a direct result of the primary cause of death. Klebsiella-infected SSOs exhibited bronchopneumonia, tracheobronchitis and/or pleuritis, enteritis, Profilicollis sp. acanthocephalan peritonitis, septic peritonitis, and septicemia. All SSO HMV isolates were capsular type K2, the serotype most associated with HMV infections in CSLs. Multiplex PCR revealed two distinct virulence gene profiles within HMV isolates and two within non-HMV isolates. In vitro experiments investigating CSL whole blood and serum killing of K. pneumoniae suggest that HMV isolates are more resistant to serum killing than non-HMV isolates.

Morbidity and mortality of young stock present economic and production challenges to livestock producers globally. In Ethiopia, calf morbidity and mortality rates, particularly due to diarrhea and respiratory disease, are high, limiting production, incomes, and the ability of farmers to improve their livelihoods. In this paper, we present findings from the combined experience of the Young Stock Mortality Reduction Consortium, which conducted epidemiological and intervention testing in calves across three production systems. This innovative alliance identified Cryptosporidium parvum and E. Coli K99 as the most common causes of diarrhea in pastoral and peri-urban calves; Strongyloides spp. as the most common fecal parasite in mixed crop–livestock and peri-urban calves; and bovine adenovirus, parainfluenza virus-3, and bovine respiratory syncytial virus as the most common respiratory pathogens in peri-urban calves. Furthermore, by improving producer knowledge with respect to fundamental livestock husbandry, feeding, housing, and neonatal care practices, calf mortality risk across production systems was reduced by 31.4 to 71.4% compared to baseline (between 10.5 and 32.1%), whereas risk of diarrhea was reduced by 52.6–75.3% (baseline between 11.4 and 30.4%) and risk of respiratory disease was reduced by 23.6–80.8% (baseline between 3.3 and 16.3%). These findings have informed scaling strategies and can potentially contribute to improved livestock productivity and human livelihoods in Ethiopia.

Freshwater bodies receive waste, feces, and fecal microorganisms from agricultural, urban, and natural activities. In this study, the probable sources of fecal contamination were determined. Also, antibiotic resistant bacteria (ARB) were detected in the two main rivers of central Chile. Surface water samples were collected from 12 sampling sites in the Maipo (n = 8) and Maule Rivers (n = 4) every 3 months, from August 2017 until April 2019. To determine the fecal contamination level, fecal coliforms were quantified using the most probable number (MPN) method and the source of fecal contamination was determined by Microbial Source Tracking (MST) using the Cryptosporidium and Giardia genotyping method. Separately, to determine if antimicrobial resistance bacteria (AMB) were present in the rivers, Escherichia coli and environmental bacteria were isolated, and the antibiotic susceptibility profile was determined. Fecal coliform levels in the Maule and Maipo Rivers ranged between 1 and 130 MPN/100-ml, and 2 and 30,000 MPN/100-ml, respectively. Based on the MST results using Cryptosporidium and Giardia host-specific species, human, cattle, birds, and/or dogs hosts were the probable sources of fecal contamination in both rivers, with human and cattle host-specific species being more frequently detected. Conditional tree analysis indicated that coliform levels were significantly associated with the river system (Maipo versus Maule), land use, and season. Fecal coliform levels were significantly (p < 0.006) higher at urban and agricultural sites than at sites immediately downstream of treatment centers, livestock areas, or natural areas. Three out of eight (37.5%) E. coli isolates presented a multidrug-resistance (MDR) phenotype. Similarly, 6.6% (117/1768) and 5.1% (44/863) of environmental isolates, in Maipo and Maule River showed and MDR phenotype. Efforts to reduce fecal discharge into these rivers should thus focus on agriculture and urban land uses as these areas were contributing the most and more frequently to fecal contamination into the rivers, while human and cattle fecal discharges were identified as the most likely source of this fecal contamination by the MST approach. This information can be used to design better mitigation strategies, thereby reducing the burden of waterborne diseases and AMR in Central Chile.

Abstract Background Calf morbidity and mortality are major constraints in Ethiopian cattle production that severely limit available replacement stock. Calf morbidity and mortality reports in Ethiopia mostly focus on market‐oriented dairy production systems. A cross‐sectional study was undertaken in central Ethiopia with the objectives of estimating the magnitude of calf morbidity and mortality across three production systems and contributing risk factors. Methods A cross‐sectional study was conducted at pastoral, mixed‐crop livestock, and dairy farms in central Ethiopia from February 2019 to June 2019 to collect 1‐year retrospective and cross‐sectional data on calf morbidity and mortality from smallholder farmers using a structured questionnaire. Results A total of 293 smallholder farmers were involved in the study. Among the households interviewed, 83% of respondents encountered feed shortages in the year prior to this study. The overall annual calf morbidity prevalence and mortality rate were 6.49% (95% CI: 4.87–8.44) and 10% (95% CI: 8.28–11.93), respectively. Morbidity was higher in Dalocha and Sululta districts in mixed crop‐livestock and peri‐urban production systems, respectively. Logistic regression analysis of potential risk factors indicated that calf morbidity was associated with the calf and dam body condition score (BCS). Calves with BCS of 3 (medium) were less likely to be morbid (odds ratio [OR]: 0.20 [95% CI: 0.07–0.56]) than calves with BCS of 1 (emaciated), and calves born from dams with a body condition score of 2 (thin) were also at lower risk (OR: 0.25 [95% CI: 0.07–0.95]) than calves born from emaciated dams. The odds of calf mortality in Awash Fentale district were higher (OR: 6.19 [95% CI: 2.09–18.32]) compared to Sululta district. Conclusions The study results revealed that the production system and management affect the magnitude of calf morbidity and mortality. We recommend improving water and feed access and resources for livestock owners to reduce calf morbidity and mortality.

OBJECTIVE Mesenchymal stromal (stem) cells (MSCs) have been studied to treat many common orthopedic injuries in horses. However, there is limited information available on when and how to use this treatment effectively. The aim of this retrospective study is to report case features, treatment protocols, and clinical outcomes in horses treated with MSCs. ANIMALS 65 horses presenting with tendinous, ligamentous, and articular injuries, and treated with MSCs prepared by a single laboratory between 2016 and 2019. Outcome information was available for 26 horses. PROCEDURES Signalment, clinical signs, diagnostic methods, treatment protocol features (prior and concurrent therapies, cell origin, dose, application site and number), and effective outcomes were analyzed. The analysis was focused on comparing the effect of different MSC treatment protocols (eg, autologous vs allogeneic) on outcome rather than the effectiveness of MSC treatment. RESULTS MSC treatment resulted in 59.1% (clinical lameness) to 76.9% (imaging structure) improvement in horses with diverse ages, breeds, sex, and lesions. The use of other therapeutic methods before MSC application (eg, anti-inflammatories, shockwave, laser, icing, resting, bandage and stack wrap, intra-articular injections, and/or surgical debridement) was shown to be statistically more effective compared to MSCs used as the primary therapeutic procedure ( P < .05). Autologous versus allogeneic treatment outcomes were not significantly different. CLINICAL RELEVANCE A prospective MSC treatment study with standardization and controls to evaluate the different features of MSC treatment protocols is needed. The various case presentations and treatment protocols evaluated can be used to inform practitioners who are currently using MSCs in clinical practice.