Analyze Diet

Topic:Horses

"Horses" is a broad topic that encompasses various aspects of equine biology, behavior, and management. This category includes studies on the anatomy, physiology, and genetics of horses, as well as their behavior, nutrition, and care. Research in this area may also cover the historical and cultural significance of horses, their roles in agriculture, sport, and therapy, and the challenges associated with their conservation and welfare. The page aggregates peer-reviewed research articles and scholarly studies that explore the multifaceted relationships between humans and horses, examining both scientific and socio-economic perspectives.
Performance of four equine pain scales and their association to movement asymmetry in horses with induced orthopedic pain.
Frontiers in veterinary science    August 12, 2022   Volume 9 938022 doi: 10.3389/fvets.2022.938022
Ask K, Andersen PH, Tamminen LM, Rhodin M, Hernlund E.This study investigated the relationship between orthopedic pain experienced at rest, and degree of movement asymmetry during trot in horses with induced reversible acute arthritis. Orthopedic pain was assessed with the Horse Grimace Scale (HGS), the Equine Utrecht University Scale of Facial Assessment of Pain (EQUUS-FAP), the Equine Pain Scale (EPS), and the Composite Orthopedic Pain Scale (CPS). Reliability and diagnostic accuracy were evaluated with intraclass correlation coefficients (ICC) and area under the curve (AUC). Unassigned: Eight healthy horses were included in this experimental s...
Arboviral Equine Encephalitides.
The Veterinary clinics of North America. Equine practice    August 12, 2022   Volume 38, Issue 2 299-321 doi: 10.1016/j.cveq.2022.04.004
Toribio RE.A number of viruses transmitted by biological vectors or through direct contact, air, or ingestion cause neurologic disease in equids. Of interest are viruses of the Togaviridae, Flaviviridae, Rhabdoviridae, Herpesviridae, Bornaviridae, and Bunyaviridae families. Many are classified as arboviruses because they use arthropod vectors, whereas others are transmitted directly via ingestion, inhalation, or integument damage. The goal of this article is to provide an overview on pathophysiologic and clinical aspects of arboviruses of equine importance, including alphaviruses (Togaviridae) and flaviv...
Neutralising antibodies to West Nile virus detected in horses in Windhoek, Namibia.
Journal of the South African Veterinary Association    August 12, 2022   Volume 93, Issue 1 39a-39c 
Molini U, Franzo G, Rautenbach I, Otto HV, Khaiseb S, Di Gennaro A, Ntahonshikira C, Baines I, Monaco F, Savini G, D'Alterio N.West Nile virus (WNV) is a vector-borne virus maintained in nature by a bird-mosquito cycle. However, it can occasionally and accidentally infect horses and human beings, leading to sometimes severe or even fatal outcomes in these species. Therefore, the monitoring of its circulation and disease occurrence is of relevance. Unfortunately, it is underdiagnosed or not diagnosed in several African counties, including Namibia, where no data is currently available for horses. In this study, 98 horses in three different stables in the Windhoek city area were investigated. They were found to have a se...
Testing individual variations of horses’ tactile reactivity: when, where, how?
Die Naturwissenschaften    August 11, 2022   Volume 109, Issue 5 41 doi: 10.1007/s00114-022-01811-y
Gueguen L, Lerch N, Grandgeorge M, Hausberger M.Tactile perception is involved in a variety of contexts (adaptations to climatic conditions, protection of the body against external dangers…) and is as important as the other sensory modalities for the survival of an individual. This tactile modality has been particularly well studied in humans, revealing high individual variations modulated by a variety of intrinsic and extrinsic factors such as age, sex, pathological disorders, or temperament. Tactility is also involved in animals' social lives, although there are disparities between species. For example, social tactile contact among hors...
Comparison of Sources and Methods for the Isolation of Equine Adipose Tissue-Derived Stromal/Stem Cells and Preliminary Results on Their Reaction to Incubation with 5-Azacytidine.
Animals : an open access journal from MDPI    August 11, 2022   Volume 12, Issue 16 2049 doi: 10.3390/ani12162049
Trachsel DS, Stage HJ, Rausch S, Trappe S, Söllig K, Sponder G, Merle R, Aschenbach JR, Gehlen H.Physiological particularities of the equine heart justify the development of an in vitro model suitable for investigations of the species-specific equine cardiac electrophysiology. Adipose tissue-derived stromal/stem cells (ASCs) could be a promising starting point from which to develop such a cardiomyocyte (CM)-like cell model. Therefore, we compared abdominal, retrobulbar, and subcutaneous adipose tissue as sources for the isolation of ASCs applying two isolation methods: the collagenase digestion and direct explant culture. Abdominal adipose tissue was most suitable for the isolation of ASC...
A review of horses as a source of spreading livestock-associated methicillin-resistant Staphylococcus aureus to human health.
Veterinary world    August 11, 2022   Volume 15, Issue 8 1906-1915 doi: 10.14202/vetworld.2022.1906-1915
Khairullah AR, Sudjarwo SA, Effendi MH, Ramandinianto SC, Widodo A, Riwu KHP.Livestock-associated methicillin-resistant Staphylococcus aureus (LA-MRSA) was first discovered in horses in 1989. Since then, LA-MRSA has begun to be considered an important strain of pathogenic bacteria in horses, which can cause LA-MRSA infection and colonization in humans with public health impacts. The anterior nares are the primary site of LA-MRSA colonization in horses, although LA-MRSA colonization may also occur in the gastrointestinal tract in horses. LA-MRSA-infected horses typically exhibit clinical infection or may not exhibit clinical infection. There are two potential risks asso...
Intravenous Magnesium Sulphate in Standing Horses: Effects on Physiological Parameters, Plasma Concentration of Magnesium and Nociceptive Threshold Tests☆.
Journal of equine veterinary science    August 11, 2022   Volume 118 104103 doi: 10.1016/j.jevs.2022.104103
La Rosa L, Twele L, Duchateau L, Gasthuys F, Kästner SB, Schauvliege S.A bolus of 50 mg kg MgSO (treatment Mg) or the same volume of saline (treatment S) was infused over 15 minutes in 5 adult healthy horses. T0 was the end of the infusion. Physiological parameters were recorded throughout the study period. Measurements of electrical, thermal, and mechanical nociceptive thresholds were performed at the pelvic limbs at baseline (before T0), and at specific timepoints. Blood samples were taken at fixed timepoints before, during and until 12 hours after the infusion. For statistical analysis, the 95% confidence intervals (CI's) for the differences in nociceptive th...
Interleukin-1β in tendon injury enhances reparative gene and protein expression in mesenchymal stem cells.
Frontiers in veterinary science    August 11, 2022   Volume 9 963759 doi: 10.3389/fvets.2022.963759
Koch DW, Berglund AK, Messenger KM, Gilbertie JM, Ellis IM, Schnabel LV.Tendon injury in the horse carries a high morbidity and monetary burden. Despite appropriate therapy, reinjury is estimated to occur in 50-65% of cases. Although intralesional mesenchymal stem cell (MSC) therapy has improved tissue architecture and reinjury rates, the mechanisms by which they promote repair are still being investigated. Additionally, reevaluating our application of MSCs in tendon injury is necessary given recent evidence that suggests MSCs exposed to inflammation (deemed MSC licensing) have an enhanced reparative effect. However, applying MSC therapy in this context is limited...
Clostridioides (Clostridium) difficile-associated disease, epiploic foramen entrapment, and gastric rupture in a Thoroughbred racehorse: case report and literature review. Asin J, Nyaoke AC, Samol MA, Arthur RM, Uzal FA.Epiploic foramen entrapment (EFE) is a common cause of small intestinal colic in horses and may lead to intestinal strangulation. Strangulating intestinal obstruction impairs the gastrointestinal outflow and can lead to secondary gastric rupture and endotoxemia. Clostridioides difficile can cause enterotyphlocolitis with colic in horses of all ages, and the process is commonly referred to as C. difficile-associated disease (CDAD). Here we report the results of the postmortem examination of a 7-y-old Thoroughbred racehorse with concurrent CDAD, EFE, and gastric rupture that was euthanized follo...
Correction: Wiśniewska et al. Heterospecific Fear and Avoidance Behaviour in Domestic Horses (Equus caballus). Animals 2021, 11, 3081.
Animals : an open access journal from MDPI    August 10, 2022   Volume 12, Issue 16 2026 doi: 10.3390/ani12162026
Wiśniewska A, Janczarek I, Wilk I, Tkaczyk E, Mierzicka M, Stanley CR, Górecka-Bruzda A.The authors wish to make the following correction to this paper [...].
Sex differences in cervical spinal cord and spinal canal development in Thoroughbred horses.
The Journal of veterinary medical science    August 10, 2022   Volume 84, Issue 10 1363-1367 doi: 10.1292/jvms.22-0234
Kondo T, Sato F, Tsuzuki N, Yamada K.Cervical vertebral stenotic myelopathy (CVSM), a common cause of cervical spinal cord compression, is a neurological disease characterized by general proprioceptive ataxia and weakness of hindlimbs that tends to develop in young adult Thoroughbred horses. Although male horses seem to be at increased risk for CVSM, the mechanism for the occurrence of sex differences in the prevalence of CVSM is still poorly understood. Hence, we hypothesized that sex differences in the development of cervical spinal cord and spinal canal would affect the development of CVSM. This study aimed to evaluate sex dif...
Prevalence of and risk factors associated with Salmonella shedding among equids presented to a veterinary teaching hospital for colic (2013-2018).
Equine veterinary journal    August 9, 2022   Volume 55, Issue 3 446-455 doi: 10.1111/evj.13864
Kilcoyne I, Magdesian KG, Guerra M, Dechant JE, Spier SJ, Kass PH.Gastrointestinal disease has been associated with shedding of Salmonella with previous studies demonstrating that horses with colic have a higher risk of acquiring and shedding Salmonella organisms. Objective: The purpose of this study was to determine the prevalence of and risk factors associated with Salmonella shedding in a colic population at a referral clinic. Methods: Retrospective case-control study. Methods: For each colic case that was positive for Salmonella (n = 56), two colic cases (n = 112) that tested negative for Salmonella, were enrolled as controls. Associations between va...
Morphological and molecular characterization of a Sarcocystis species infecting donkeys from China.
Parasitology research    August 9, 2022   Volume 121, Issue 10 2917-2926 doi: 10.1007/s00436-022-07616-2
Zhang M, Wei K, Wu Z, Sun J, Hu J, Deng S, Tao J.There is considerable confusion concerning the relationships among species of Sarcocystis found in donkeys and horses. Here, we describe a Sarcocystis species in Chinese donkeys (Equus asinus). Sarcocysts were found in 12 of 32 (37.5%) adult donkeys. By light microscopy, they were divided into two types, thin-walled and thick-walled. The thin-walled were macroscopic (up to 320 μm wide) and had short club-like protrusions (up to 2.7 μm long); the thick-walled were microscopic (up to 135 μm wide) and had villar protrusions (up to 5.4 μm long). Ultrastructures of the two types exhibited s...
Hoof morphometry in a population of lame and nonlame working donkeys in Pakistan.
Equine veterinary journal    August 9, 2022   Volume 55, Issue 3 435-445 doi: 10.1111/evj.13861
Khan RZU, Rosanowski SM, Parkes RSV.Hoof morphometry, conformation and shoeing practices have all been associated with lameness in horses. Hoof morphometry in working donkeys in Pakistan has not been objectively measured. Objective: To quantitatively assess hoof morphology in donkeys, to identify factors underlying hoof morphology, and interrelationships between conformation, lameness, and shoeing status. Methods: Cross-sectional study. Methods: Donkeys were assessed in-harness using a modified five-point lameness scale by two veterinarians and digital photographs of front hooves taken alongside a grid. Factor analysis was used ...
Non-contact respiratory measurement in a horse in standing position using millimeter-wave array radar.
The Journal of veterinary medical science    August 9, 2022   Volume 84, Issue 10 1340-1344 doi: 10.1292/jvms.22-0238
Matsumoto T, Okumura S, Hirata S.This study aimed to apply radar technology to a large quadruped animal. We first developed a non-contact respiration measurement system using millimeter-wave array radar for a horse in standing position. Specifically, we measured the respiration of a stationary domestic horse in stables. Simultaneously, we measured the respiration rate using infrared thermography and developed a method for analyzing the radar information while verifying the rate of agreement. Our results suggested that the radar technology detected breathing and accurately measured the respiration of a horse, despite variation...
A Comparison of Methods to Maintain the Equine Cecal Microbial Environment In Vitro Utilizing Cecal and Fecal Material.
Animals : an open access journal from MDPI    August 8, 2022   Volume 12, Issue 15 2009 doi: 10.3390/ani12152009
MacNicol JL, Renwick S, Ganobis CM, Allen-Vercoe E, Weese JS, Pearson W.The equine gastrointestinal (GI) microbiota is intimately related to the horse. The objective of the current study was to evaluate the microbiome and metabolome of cecal inoculum maintained in an anaerobic chamber or chemostat batch fermenter, as well as the fecal slurry maintained in an anaerobic chamber over 48 h. Cecal and fecal content were collected from healthy adult horses immediately upon death. Cecal fluid was used to inoculate chemostat vessels (chemostat cecal, = 11) and vessels containing cecal fluid (anaerobic cecal, = 15) or 5% fecal slurry (anaerobic fecal, = 6) were maintain...
Sphingolipidome of plasma, liver, and adipose tissues and its association with insulin response to oral glucose testing in Icelandic horses.
American journal of physiology. Regulatory, integrative and comparative physiology    August 8, 2022   Volume 323, Issue 4 R397-R409 doi: 10.1152/ajpregu.00018.2022
Jorge-Smeding E, Warnken T, Grob AJ, Feige K, Pudert T, Leung YH, Go YY, Kenéz Á.Insulin dysregulation (ID) is a determinant of equine metabolic syndrome. Among the sphingolipids, ceramides contribute to the development of ID; however, the cross talk between the liver and adipose tissue (AT) depots and the variation among AT depots in terms of ceramide metabolism are not well understood. We aimed to characterize the sphingolipidome of plasma, liver, and AT (nuchal, NUAT; subcutaneous, SCAT; omental, OMAT; retroperitoneal, RPAT) and their associations with insulin response to oral glucose testing (OGT) in normoinsulinemic and hyperinsulinemic horses. Plasma, liver, and AT s...
The effect of priming and duration of oestradiol benzoate treatment before progesterone administration on embryo development and survival in anestrous recipient mares.
Reproduction in domestic animals = Zuchthygiene    August 8, 2022   Volume 57, Issue 11 1474-1477 doi: 10.1111/rda.14220
Oquendo PS, Silva ESM, Oquendo FMG, Cuervo-Arango J, Beletti ME.The effect of three different hormonal protocols to prepare anestrous recipient mares on embryo survival was evaluated. The first group consisted of only progesterone administration (NE) 4 days before embryo transfer, while the recipients from the other two groups received a single administration of 2.5 mg of oestradiol benzoate (SE) 2 days earlier or 8 mg of oestradiol split in increasing doses for 5 consecutive days (LE) ending 3 days before progesterone treatment. The likelihood of recovering an embryo 2 days after transfer was 46.1% (6/13), 62.5% (5/8) and 85.7% (6/7) for recipie...
Biomechanical Comparison of a Headless Compression Screw Fastener and AO Cortical Bone Screw for Fixation of a Simulated Equine Third Carpal Bone Slab Fracture.
Journal of equine veterinary science    August 7, 2022   Volume 118 104094 doi: 10.1016/j.jevs.2022.104094
Salinger A, Mochal-King C, Clinton K, Priddy LB, Elder S, Fontenot R, Eddy A, Wills R, Jaffe M.Frontal plane slab fractures account for the majority of third carpal bone (C3) fractures in racing and performance horses. Recommended treatment is stabilization with a lagged AO cortical screw. Associated complications are fragment splitting, fragment spinning, and irritation of dorsal soft tissue structures. A novel, headless, cannulated screw with interlocking threads the Headless Compression Screw Fastener (HCSF) has been developed to resist multidirectional forces and bending moments; however, it has not been applied in the horse. Simulated C3 frontal plane slab fractures were created in...
Use of the SGLT2 inhibitor canagliflozin for control of refractory equine hyperinsulinemia and laminitis.
Open veterinary journal    August 7, 2022   Volume 12, Issue 4 511-518 doi: 10.5455/OVJ.2022.v12.i4.14
Kellon EM, Gustafson KM.Hyperinsulinemia associated with pituitary pars intermedia dysfunction (PPID) and/or equine metabolic syndrome is well documented to put horses at high risk of laminitis. While dietary control of simple sugars and starch is the most effective therapy to control hyperinsulinemia, some horses fail to respond. Ten horses with hyperinsulinemia refractory to diet control, metformin, levothyroxine, and pergolide (if diagnosed with PPID) were treated with sodium-glucose cotransporter-2 inhibitor canagliflozin (Invokana®). Nine horses were hyperglycemic (>5.5 mmol/l) or had a history of hyperglycemia...
Nocardioform placentitis in a sample population of mares foaling in southeastern Pennsylvania and northeastern Maryland in 2020.
Theriogenology    August 6, 2022   Volume 192 52-61 doi: 10.1016/j.theriogenology.2022.08.002
Stonehouse O, Stefanovski D, Bowman B, Sertich PL, Demchur J, Lewis GM, Turner RM, Turner RMO.Nocardioform placentitis (NP) has been associated with mid to late pregnancy loss in mares. To date, disease outbreaks have been described only in central Kentucky, although sporadic, isolated cases have been reported globally. This study describes a series of cases of NP that occurred in a sample population of 299 mares foaling in southeastern Pennsylvania and northeastern Maryland in 2020. These cases coincided with an outbreak of NP that occurred in Kentucky that same year. On farms that reported information on both normal and abnormal foalings, nocardioform organisms/DNA were isolated from...
Preliminary evaluation of the effects of a 1:1 inspiratory-to-expiratory ratio in anesthetized and ventilated horses.
Veterinary anaesthesia and analgesia    August 6, 2022   Volume 49, Issue 6 645-649 doi: 10.1016/j.vaa.2022.07.009
To describe some cardiorespiratory effects of an inspiratory-to-expiratory (IE) ratio of 1:1 compared with 1:3 in ventilated horses in dorsal recumbency. Methods: Randomized crossover experimental study. Methods: A total of eight anesthetized horses, with 444 (330-485) kg body weight [median (range)]. Methods: Horses were ventilated in dorsal recumbency with a tidal volume of 15 mL kg and a respiratory rate of 8 breaths minute, and IE ratios of 1:1 (IE1:1) and 1:3 (IE1:3) in random order, each for 25 minutes after applying a recruitment maneuver. Spirometry, arterial blood gases and dobutamine...
Noncompartmental pharmacokinetics of three intravenous mycophenolate mofetil concentrations in healthy Standardbred mares.
Veterinary dermatology    August 5, 2022   Volume 34, Issue 3 222-234 doi: 10.1111/vde.13109
Burroughs DL, Lorch G, Guo Y, Hill K, Schroeder EL, Cole LK, Phelps MA.Mycophenolate mofetil (MMF) is the prodrug of mycophenolic acid (MPA) which acts as an immunosuppressive agent. During the biotransformation of MMF to MPA, additional metabolites including MPA phenol glucuronide (MPAG), MPA acyl glucuronide (AcMPAG) and MPA phenol glucoside (MPG) are formed. Objective: To define the noncompartmental pharmacokinetic (PK) parameters of three single doses of intravenous (i.v.) MMF and its downstream metabolites in healthy horses. Methods: Six healthy Standardbred mares. Methods: Generic MMF (Par Pharmaceuticals; Chestnut Ridge, NY, USA) was reconstituted and admi...
The Microbiological Quality of Concentrates for Horses-A Retrospective Study on Influencing Factors and Associations with Clinical Symptoms Reported by Owners or Referring Vets.
Veterinary sciences    August 5, 2022   Volume 9, Issue 8 413 doi: 10.3390/vetsci9080413
Intemann S, Reckels B, Schubert DC, Wolf P, Kamphues J, Visscher C.Evidence has already been provided that feed-borne mold spores and endotoxins can trigger chronic, non-infectious respiratory disease if inhaled. Furthermore, deficiencies in feed microbiology are suspected to trigger gastrointestinal and liver disorders in horses, but the connection needs further clarification. Most of the previous studies regarding horse feed hygiene focused on forage, whereas research regarding hygienic quality of concentrates is scarce. In the present study, results of reports on hygienic quality of compound feed and cereals for horses were evaluated secondarily. Results i...
Plasma syndecan-1 concentration as a biomarker for endothelial glycocalyx degradation in septic adult horses.
Equine veterinary journal    August 5, 2022   Volume 55, Issue 3 456-462 doi: 10.1111/evj.13862
Hobbs KJ, Johnson PJ, Wiedmeyer CE, Schultz L, Foote CA.Limited information is available regarding endothelial glycocalyx degradation during sepsis in horses. Plasma syndecan-1 concentrations are increased in consequence of sepsis in other species and have been useful for prognostication. Objective: To determine whether plasma syndecan-1 levels are increased in adult horses affected with sepsis. Methods: Retrospective cohort study. Methods: Adult horses were assigned to one of three groups based on results of physical and laboratory examinations, clinical diagnosis, and results of previously described SIRS classification: Group 1 horses included he...
Fitness cost conferred by the novel erm(51) and rpoB mutation on environmental multidrug resistant-Rhodococcus equi.
Veterinary microbiology    August 5, 2022   Volume 273 109531 doi: 10.1016/j.vetmic.2022.109531
Rivera-Velez A, Huber L, Sinha S, Cohen ND.Rhodococcus equi is a common cause of severe pneumonia in foals. Emergence of macrolide-resistant R. equi isolated from foals and their environment has been reported in the United States. A novel erm(51) gene was recently identified in R. equi in soil from horse farms in Kentucky. Our objective was to determine the effect of the erm(51) gene and associated rpoB mutation on the fitness of multidrug resistant-R. equi (MDR-R. equi) under different nutrient conditions. Bacterial growth curves were generated for 3 MDR-R. equi isolates and 3 wild-type (WTN) R. equi isolates recovered from environmen...
Serum immunoglobulin G concentration after plasma transfusion in neonatal foals with hypogammaglobulinemia in various health status.
Journal of equine veterinary science    August 5, 2022   Volume 117 104093 doi: 10.1016/j.jevs.2022.104093
Sievert M, Schuler G, Wehrend A.Due to the time-limited intestinal uptake of colostral immunoglobulins, the suggested treatment of hypogammaglobulinemia in new-born foals is usually plasma transfusion. The aims of this study were twofold: firstly, to investigate the course of serum IgG concentration after plasma transfusion in newborn foals; and secondly, to determine the amount of transfusion required for a significant increase in serum IgG concentration. For this purpose, the IgG concentration was measured in 23 foals at three different points in time: before transfusion, 1 hour after transfusion, and 24 hours after transf...
An Extra-Articular Surgical Approach to Subchondral Bone Cysts in the Humeral Head and Talus in Two Horses.
Journal of equine veterinary science    August 5, 2022   Volume 118 104092 doi: 10.1016/j.jevs.2022.104092
Ravanetti P, Kühnle C, Lechartier A, Zucca E.To date, only a few reports describe the treatment. The present report describes an extraarticular surgical approach, with the insertion of an absorbable implant, to treat a Subchondral cystic lesion (SCL) in the humeral head 3year old racing Thoroughbred & in the talus of a 11year old Arabian horse. SCLs were radiographically visible and associated with severe lameness. Scintigraphy showed focal intense radiopharmaceutical uptake in both cases, and CT scan revealed signs of osteoarthrosis associated with SCL in the talus. The use of a biocompatible, osteoinductive and osteoconductive implant ...
Mitochondrial Dysfunctions and Potential Molecular Markers in Sport Horses.
International journal of molecular sciences    August 4, 2022   Volume 23, Issue 15 8655 doi: 10.3390/ijms23158655
Dzięgielewska A, Dunislawska A.Mitochondria are an essential part of most eukaryotic cells. The crucial role of these organelles is the production of metabolic energy, which is converted into ATP in oxidative phosphorylation. They are also involved in and constitute apoptosis, the site of many metabolic processes. Some of the factors that negatively affect mitochondria are stress, excessive exercise, disease, and the aging process. Exercise can cause the release of large amounts of free radicals, inflammation, injury, and stress. All of these factors can contribute to mitochondrial dysfunction, which can consistently lead t...
Potent Neutralizing Activity of Polyclonal Equine Antibodies Against Severe Acute Respiratory Syndrome Coronavirus 2 Variants of Concern.
The Journal of infectious diseases    August 4, 2022   Volume 227, Issue 1 35-39 doi: 10.1093/infdis/jiac331
Luczkowiak J, Radreau P, Nguyen L, Labiod N, Lasala F, Veas F, Herbreteau CH, Delgado R.Several anti-severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) monoclonal antibodies (mAbs) have received emergency authorization for coronavirus disease 2019 (COVID-19) treatment. However, most of these mAbs are not active against the highly mutated Omicron SARS-CoV-2 subvariants. We have tested a polyclonal approach of equine anti-SARS-CoV-2 F(ab')2 antibodies that achieved a high level of neutralizing potency against all SARS-CoV-2 variants of concern tested including Omicron BA.1, BA.2, BA.2.12 and BA.4/5. A repertoire of antibodies targeting conserved epitopes in different regi...