Analyze Diet

Topic:Age Factors

Age factors in horses encompass a range of physiological and developmental changes that occur as horses mature from foals to adults and eventually into their senior years. These factors include variations in metabolic rate, immune function, and musculoskeletal development, which can influence a horse's health, performance, and nutritional needs. Age-related changes can also affect how horses respond to medications, recover from injuries, and maintain overall vitality. Researchers study these aspects to understand better how age impacts equine health and management. This page compiles peer-reviewed research studies and scholarly articles that explore the effects of age on equine physiology, health management, and disease susceptibility.
Seroepidemiology of Sarcocystis neurona and Neospora hughesi infections in domestic donkeys (Equus asinus) in Durango, Mexico.
Parasite (Paris, France)    July 21, 2017   Volume 24 27 doi: 10.1051/parasite/2017030
There is currently no information regarding Sarcocystis neurona and Neospora hughesi infections in donkeys in Mexico. Here, we determined the presence of antibodies against S. neurona and N. hughesi in donkeys in the northern Mexican state of Durango. Serum samples of 239 domestic donkeys (Equus asinus) were assayed for S. neurona and N. hughesi antibodies using home-made enzyme-linked immunoassays; six (2.5%) of the 239 donkeys tested seropositive for S. neurona. The seroprevalence of S. neurona infection was comparable among donkeys regardless of their origin, health status, or sex. Multivar...
Beyond scoring systems: usefulness of morphometry considering demographic variables, to evaluate neck and overall obesity in Andalusian horses.
Animal : an international journal of animal bioscience    July 17, 2017   Volume 12, Issue 3 597-605 doi: 10.1017/S1751731117001628
Martin-Gimenez T, Aguirre-Pascasio CN, de Blas I.Morphometry has proven to be a useful tool, both for the clinician and horse owners, for evaluating the body condition in equids due to its objectivity, easiness and capacity for detection of important metabolic disturbances. However, limited information is available on the use of morphometric ratios to characterize regional and overall adiposity and much less about their application in different genders, ages and horses with different levels of obesity. The objectives were to evaluate body and neck absolute measurements and ratios; factors affecting them such as the influence of gender, age, ...
Equine recurrent uveitis in western Canadian prairie provinces: A retrospective study (2002-2015).
The Canadian veterinary journal = La revue veterinaire canadienne    July 13, 2017   Volume 58, Issue 7 717-722 
Sandmeyer LS, Bauer BS, Feng CX, Grahn BH.The objectives of this study were to determine the demographics of horses with equine recurrent uveitis (ERU) presenting to the Western College of Veterinary Medicine and to describe and compare the prognosis of ERU in the Appaloosa with that in other breeds. Horses diagnosed with ERU by a veterinary ophthalmologist between 2002 and 2015 were included. Eye lesions were classified as mild, moderate, or severe based on clinical manifestations. Breed, age, severity, blindness, and final outcome were evaluated. Thirty-two horses fit the inclusion criteria; 62.5% were Appaloosas. Mean age at presen...
Parasagittal fractures of the proximal phalanx in Thoroughbred racehorses in the UK: Outcome of repaired fractures in 113 cases (2007-2011).
Equine veterinary journal    July 6, 2017   Volume 49, Issue 6 784-788 doi: 10.1111/evj.12707
Smith MRW, Corletto FC, Wright IM.Thirty years have elapsed since the last published review of outcome following fracture of the proximal phalanx in Thoroughbred racehorses in the UK and contemporary results are needed to be able to advise of expected outcome. Objective: Collect and analyse outcome data following repair of fractures of the proximal phalanx in Thoroughbred racehorses in the UK. Methods: Retrospective case series. Methods: Case records of all Thoroughbred racehorses admitted to Newmarket Equine Hospital for evaluation of a parasagittal fracture of the proximal phalanx during a 5 years period were reviewed. Follo...
West Nile virus infection in horses, Indian ocean.
Comparative immunology, microbiology and infectious diseases    July 4, 2017   Volume 53 45-49 doi: 10.1016/j.cimid.2017.06.006
Cardinale E, Bernard C, Lecollinet S, Rakotoharinome VM, Ravaomanana J, Roger M, Olive MM, Meenowa D, Jaumally MR, Melanie J, Héraud JM, Zientara S....The circulation of West Nile virus (WNV) in horses was investigated in the Southwest Indian ocean. In 2010, blood samples were collected from a total of 303 horses originating from Madagascar, Mauritius, Reunion and the Seychelles and tested for WNV-specific antibodies. An overall seroprevalence of 27.39% was detected in the Indian Ocean with the highest WNV antibody prevalence of 46.22% (95% CI: [37.4-55.2%]) in Madagascar. The age and origin of the horses were found to be associated with the WNV infection risk. This paper presents the first seroprevalence study investigating WN fever in hors...
Outcomes after medical and surgical interventions in horses with temporohyoid osteoarthropathy.
Equine veterinary journal    July 3, 2017   Volume 49, Issue 6 770-775 doi: 10.1111/evj.12701
Espinosa P, Nieto JE, Estell KE, Kass PH, Aleman M.Temporohyoid osteoarthropathy (THO) is a cause of neurological disease in horses that is characterised by facial and vestibulocochlear nerve deficits. Studies reporting and comparing survival following medical or surgical treatment of THO are lacking. Objective: To compare survival and prognosis in horses with THO treated medically or surgically, and to report surgical complications. Methods: Retrospective study. Methods: The medical records of horses diagnosed with THO were retrieved, and data on signalment, clinical signs and duration, corneal ulceration and bilateral occurrence were recorde...
The Effect of Geographic Location on Circannual Adrenocorticotropic Hormone Plasma Concentrations in Horses in Australia.
Journal of veterinary internal medicine    June 29, 2017   Volume 31, Issue 5 1533-1540 doi: 10.1111/jvim.14782
Secombe CJ, Tan RHH, Perara DI, Byrne DP, Watts SP, Wearn JG.Longitudinal evaluation of plasma endogenous ACTH concentration in clinically normal horses has not been investigated in the Southern Hemisphere. Objective: To longitudinally determine monthly upper reference limits for plasma ACTH in 2 disparate Australian geographic locations and to examine whether location affected the circannual rhythm of endogenous ACTH in the 2 groups of horses over a 12-month period. Methods: Clinically normal horses <20 years of age from 4 properties (institutional herd and client owned animals) in Perth (n = 40) and Townsville (n = 41) were included in the study. M...
Epidemiology and molecular detection of equine herpesviruses in western Algeria in 2011.
Veterinary microbiology    June 27, 2017   Volume 207 205-209 doi: 10.1016/j.vetmic.2017.06.017
Laabassi F, Hue E, Fortier C, Morilland E, Legrand L, Hans A, Pronost S.An episode of acute equine respiratory infection was reported in western Algeria (Tiaret province) between February and March 2011, affecting a large population of horses. Nasal swabs (n=100) were taken from horses aged between 1 and 27 years, presenting with cough and mucopurulent nasal discharge. The prevalence of equine respiratory virus infections was examined using quantitative polymerase chain reaction (qPCR). One, or more, of four equine respiratory viruses were detected in the nasal swabs of 90 of 100 horses (90%) and the detection rate of equine herpesvirus type 1 (EHV-1), equine herp...
Racing performance of Standardbred trotting horses undergoing surgery of the carpal flexor sheath and age- and sex-matched control horses.
American journal of veterinary research    June 27, 2017   Volume 78, Issue 7 847-853 doi: 10.2460/ajvr.78.7.847
Carmalt JL, Johansson BC, Zetterström SM, McOnie RC.OBJECTIVE To determine factors affecting race speed in Swedish Standardbred horses undergoing surgery of the carpal flexor sheath (CFS), to investigate whether preoperative racing speed was associated with specific intraoperative findings and whether horses returned to racing, and to compare the performance of horses undergoing surgery of the CFS with that of age- and sex-matched control horses. ANIMALS 149 Swedish Standardbred trotters undergoing surgery of the CFS and 274 age- and sex-matched control horses. PROCEDURES Medical records of CFS horses were examined. Racing data for CFS and cont...
Cross-validation analysis for genetic evaluation models for ranking in endurance horses.
Animal : an international journal of animal bioscience    June 21, 2017   Volume 12, Issue 1 20-27 doi: 10.1017/S1751731117001331
García-Ballesteros S, Varona L, Valera M, Gutiérrez JP, Cervantes I.Ranking trait was used as a selection criterion for competition horses to estimate racing performance. In the literature the most common approaches to estimate breeding values are the linear or threshold statistical models. However, recent studies have shown that a Thurstonian approach was able to fix the race effect (competitive level of the horses that participate in the same race), thus suggesting a better prediction accuracy of breeding values for ranking trait. The aim of this study was to compare the predictability of linear, threshold and Thurstonian approaches for genetic evaluation of...
Individual quality and age but not environmental or social conditions modulate costs of reproduction in a capital breeder.
Ecology and evolution    June 15, 2017   Volume 7, Issue 15 5580-5591 doi: 10.1002/ece3.3082
Debeffe L, Poissant J, McLoughlin PD.Costs associated with reproduction are widely known to play a role in the evolution of reproductive tactics with consequences to population and eco-evolutionary dynamics. Evaluating these costs as they pertain to species in the wild remains an important goal of evolutionary ecology. Individual heterogeneity, including differences in individual quality (i.e., among-individual differences in traits associated with survival and reproduction) or state, and variation in environmental and social conditions can modulate the costs of reproduction; however, few studies have considered effects of these ...
Serological survey for Brucella antibodies in donkeys of north-eastern Nigeria.
Tropical animal health and production    June 14, 2017   Volume 49, Issue 6 1211-1216 doi: 10.1007/s11250-017-1318-4
Tijjani AO, Junaidu AU, Salihu MD, Farouq AA, Faleke OO, Adamu SG, Musa HI, Hambali IU.A cross-sectional epidemiological study was conducted to determine seroprevalence and risk factors influencing the presence of Brucella antibodies in donkeys of Borno State, north-eastern Nigeria. The study aimed at providing baseline information that may be used in planning a control policy against equine brucellosis. Blood samples were collected from 601 donkeys, comprised of 374 males and 227 females from the six agricultural zones of the state between March 2013 and September 2014. The sera obtained were tested for Brucella antibodies using Rose Bengal plate test (RBPT) and competitive enz...
Corneal sensitivity and tear production in 108 horses with ocular disease.
Veterinary ophthalmology    June 9, 2017   Volume 21, Issue 1 76-81 doi: 10.1111/vop.12481
Knickelbein KE, Scherrer NM, Lassaline M.To compare corneal sensitivity and tear production in horses with keratitis to horses with other ocular disease. Methods: Retrospective medical record review was used to identify equine patients presented during a 1-year period for an ocular complaint who had Schirmer Tear Test (STT) or Corneal Touch Threshold (CTT) measured. Variables studied included patient age and sex; affected eye; category of presenting ocular complaint (keratitis vs. other ocular complaint); STT; and CTT. Patients with a complaint of ulcerative keratitis, immune-mediated keratitis, and stromal abscess were categorized i...
The refractive state of the eye in Icelandic horses with the Silver mutation.
BMC veterinary research    June 2, 2017   Volume 13, Issue 1 153 doi: 10.1186/s12917-017-1059-7
Johansson MK, Jäderkvist Fegraeus K, Lindgren G, Ekesten B.The syndrome Multiple Congenital Ocular Anomalies (MCOA) is a congenital eye disorder in horses. Both the MCOA syndrome and the Silver coat colour in horses are caused by the same missense mutation in the premelanosome protein (PMEL) gene. Horses homozygous for the Silver mutation (TT) are affected by multiple ocular defects causing visual impairment or blindness. Horses heterozygous for the Silver mutation (CT) have less severe clinical signs, usually cysts arising from the ciliary body iris or retina temporally. It is still unknown if the vision is impaired in horses heterozygous for the Sil...
Comparison of the fecal bacterial microbiota of healthy and diarrheic foals at two and four weeks of life.
BMC veterinary research    May 30, 2017   Volume 13, Issue 1 144 doi: 10.1186/s12917-017-1064-x
Schoster A, Staempfli HR, Guardabassi LG, Jalali M, Weese JS.Diarrhea in foals affects up to 60% of foals during the first six months of life. The effect of diarrhea on the fecal bacterial microbiota in foals has not been investigated. Little is known on the fecal bacterial microbial richness and diversity of foals at a young age. The objective was to compare the fecal bacterial microbiota of healthy foals to foals with diarrhea at two and four weeks of life. Methods: Fecal samples were collected from foals (n = 20) at 1-14 (T1) and 15-28 (T2) days of age and analyzed using high throughput sequencing. Differences in relative abundance of bacterial tax...
The association between oral examination findings and computed tomographic appearance of the equine temporomandibular joint.
Equine veterinary journal    May 25, 2017   Volume 49, Issue 6 780-783 doi: 10.1111/evj.12693
Carmalt JL, Simhofer H, Bienert-Zeit A, Rawlinson JE, Waldner CL.The temporomandibular joint (TMJ) forms the junction between the maxilla and mandible. Movement of the jaw and resulting masticatory forces have been extensively studied in the horse; however, less is known about the inter-relationship between this joint and oral and dental pathology. Objective: To determine the association between specific oral and dental pathologies and anatomical variations of the TMJ imaged with computed tomography (CT) in horses with asymptomatic TMJs. Methods: Retrospective cross-sectional study. Methods: Horses (n = 201) from three practices with a complete oral exami...
Seroprevalences of anti-Sarcocystis neurona and anti-Neospora hughesi antibodies among healthy equids in the United States.
Journal of the American Veterinary Medical Association    May 17, 2017   Volume 250, Issue 11 1291-1301 doi: 10.2460/javma.250.11.1291
James KE, Smith WA, Conrad PA, Packham AE, Guerrero L, Ng M, Pusterla N.OBJECTIVE To describe the general seroprevalence of anti-Sarcocystis neurona and anti-Neospora hughesi antibodies among healthy equids by use of indirect fluorescent antibody tests and determine potential risk factors for seropositivity. DESIGN Cross-sectional study. SAMPLE Whole blood samples collected from 5,250 equids (1 sample/animal) across 18 states in the United States during October 2013. PROCEDURES Information regarding potential risk factors (geographic region, breed, primary use, sex, and age) was collected along with the blood samples. For each equid, an indirect fluorescent antibo...
Complications and risk factors of castration with primary wound closure: Retrospective study in 159 horses.
The Canadian veterinary journal = La revue veterinaire canadienne    May 11, 2017   Volume 58, Issue 5 466-471 
Robert MP, Chapuis RJJ, de Fourmestraux C, Geffroy OJ.Castration with primary wound closure reportedly has lower complication rates and shorter recovery periods compared to castration with second intention healing. However, little is known about risk factors associated with complications using primary wound closure. Medical records of 159 horses castrated and having primary wound closure were reviewed. Main short-term complications were: scrotal hematoma in 12 horses (7.6%), signs of colic in 6 horses (3.8%), fever in 4 horses (2.5%), and peri-incisional edema in 3 horses (1.9%). As for long-term complications, 24 out of 105 (23%) horses sustaine...
Lack of significant associations with early career performance suggest no link between the DMRT3 “Gait Keeper” mutation and precocity in Coldblooded trotters.
PloS one    May 10, 2017   Volume 12, Issue 5 e0177351 doi: 10.1371/journal.pone.0177351
Jäderkvist Fegraeus K, Lawrence C, Petäjistö K, Johansson MK, Wiklund M, Olsson C, Andersson L, Andersson LS, Røed KH, Ihler CF, Strand E....The Swedish-Norwegian Coldblooded trotter (CBT) is a local breed in Sweden and Norway mainly used for harness racing. Previous studies have shown that a mutation from cytosine (C) to adenine (A) in the doublesex and mab-3 related transcription factor 3 (DMRT3) gene has a major impact on harness racing performance of different breeds. An association of the DMRT3 mutation with early career performance has also been suggested. The aim of the current study was to investigate this proposed association in a randomly selected group of CBTs. 769 CBTs (485 raced, 284 unraced) were genotyped for the DMR...
Preantral follicle density in ovarian biopsy fragments and effects of mare age.
Reproduction, fertility, and development    April 27, 2017   Volume 29, Issue 5 867-875 doi: 10.1071/RD15402
Alves KA, Alves BG, Gastal GDA, Haag KT, Gastal MO, Figueiredo JR, Gambarini ML, Gastal EL.The aims of the present study were to: (1) evaluate preantral follicle density in ovarian biopsy fragments within and among mares; (2) assess the effects of mare age on the density and quality of preantral follicles; and (3) determine the minimum number of ovarian fragments and histological sections needed to estimate equine follicle density using a mathematical model. The ovarian biopsy pick-up method was used in three groups of mares separated according to age (5-6, 7-10 and 11-16 years). Overall, 336 preantral follicles were recorded with a mean follicle density of 3.7 follicles per cm. Fol...
The influence of age, antral follicle count and diestrous ovulations on estrous cycle characteristics of mares.
Theriogenology    April 13, 2017   Volume 97 34-40 doi: 10.1016/j.theriogenology.2017.04.019
Claes A, Ball BA, Scoggin KE, Roser JF, Woodward EM, Davolli GM, Squires EL, Troedsson MHT.Reproductive aging must be well understood to optimize the reproductive management of older mares and to predict their reproductive life-span. The objectives of this study were to: 1) examine age-related differences in follicular dynamics, endocrine profiles, and primordial follicle counts, 2) evaluate the influence of antral follicle count (AFC) on age-related changes in follicular parameters, and 3) determine the influence of diestrous ovulations on the estrous cycle. Young (3-8yr; n = 10), middle-aged (9-18 yr; n = 16), and old (>18 yr; n = 19) light horse mares were examined wit...
Age-related effects on markers of inflammation and cartilage metabolism in response to an intra-articular lipopolysaccharide challenge in horses.
Journal of animal science    April 6, 2017   Volume 95, Issue 2 671-680 doi: 10.2527/jas.2016.1078
Kahn MK, Coverdale JA, Leatherwood JL, Arnold CE, Dabareiner RA, Bradbery AN, Millican AA, Welsh TH.Eighteen Quarter Horses were used in a randomized complete design for a 28-d experiment to evaluate age-related effects on inflammation and cartilage turnover after induction of a single inflammatory insult using lipopolysaccharide (LPS). Horses were grouped by age as yearlings (3 males and 3 females), 2 to 3 yr olds (2/3 yr old; 2 males and 4 females), and skeletally mature 5 to 8 yr olds (mature; 2 males and 4 females). On d 0, all horses were individually housed and fed diets that met or exceeded requirements. On d 14, horses were challenged with an intra-articular injection of LPS. Radial ...
Frequent occurrence of nonprimate hepacivirus infections in Thoroughbred breeding horses – A cross-sectional study for the occurrence of infections and potential risk factors.
Veterinary microbiology    April 4, 2017   Volume 203 315-322 doi: 10.1016/j.vetmic.2017.03.030
Reichert C, Campe A, Walter S, Pfaender S, Welsch K, Ruddat I, Sieme H, Feige K, Steinmann E, Cavalleri JMV.Recently, several new hepaciviruses have been identified of which the nonprimate hepacivirus (NPHV) - the closest relative to hepatitis C virus (HCV) discovered to date - is highly prevalent in horses. However, potential risk factors for the transmission of NPHV among horses remain still unknown. Therefore, the objective of this study was to investigate the occurrence of NPHV infections in Thoroughbreds in northern and western Germany and to identify potential risk factors associated with NPHV infections. Using a cross-sectional study design, a total of 733 serum samples from Thoroughbred broo...
Anoplocephala sp. (Cestoda, Cyclophyllidea) infection in horses in Central Italy.
Veterinaria italiana    April 4, 2017   Volume 53, Issue 1 85-87 doi: 10.12834/VetIt.155.455.3
Roncoron C, Fagiolo A, Amoruso C, De Liberato C.Species of Anoplocephalidae are cestodes affecting equines worldwide and causing many intestinal disorders. Between October 2010 and September 2013, 284 faecal samples of horses originating from Lazio Region (Central Italy) were tested for the presence of Anoplocephala sp. eggs by a classic copromicroscopic technique. Data regarding pasture‑dependence/non dependence, age, and sex of the horses were also collected. Statistical analysis, aimed at detecting possible associations between these variables and Anoplocephala sp. prevalence, was performed. Anoplocephala sp. eggs were found in 13% of ...
Age-related variation in the cellular composition of equine bronchoalveolar lavage fluid.
Veterinary clinical pathology    March 27, 2017   Volume 46, Issue 2 344-353 doi: 10.1111/vcp.12473
Hostetter SJ, Clark SK, Gilbertie JM, Wiechert SA, Jones DE, Sponseller BA.Previous reports reveal variation in the cellular composition of equine bronchoalveolar lavage fluid (BALF). Objective: The purpose of this study was to compare the profiles of BALF from horses to assess age-related differences. Serial BALF samples were collected from the same individuals over a one-year period to identify changes in individual animals as they aged. Methods: Collection of BALF was performed on horses aged one week and one, 2, 6, and 12 months. Total nucleated cell count (TNCC), protein concentration, and cytology were assessed. Longitudinal analysis was performed and compared ...
Serum snoRNAs as biomarkers for joint ageing and post traumatic osteoarthritis.
Scientific reports    March 2, 2017   Volume 7 43558 doi: 10.1038/srep43558
Steinbusch MM, Fang Y, Milner PI, Clegg PD, Young DA, Welting TJ, Peffers MJ.The development of effective treatments for the age-related disease osteoarthritis and the ability to predict disease progression has been hampered by the lack of biomarkers able to demonstrate the course of the disease. Profiling the expression patterns of small nucleolar RNAs (snoRNAs) in joint ageing and OA may provide diagnostic biomarkers and therapeutic targets. This study determined expression patterns of snoRNAs in joint ageing and OA and examined them as potential biomarkers. Using SnoRNASeq and real-time quantitative PCR (qRT-PCR) we demonstrate snoRNA expression levels in murine age...
The Influence of the Size, Age and Sex on the Computed Tomographic Measured Size of the Pituitary Gland in Normal Horses.
Anatomia, histologia, embryologia    February 27, 2017   Volume 46, Issue 3 267-273 doi: 10.1111/ahe.12266
Crijns CP, Van Bree HJ, Broeckx BJG, Schauvliege S, Van Loon G, Martens A, Vanderperren K, Dingemanse WB, Gielen IM.The objective of this study was to examine the influence of the size, age and sex of the horse on the size of the pituitary gland and determine the possibility of using the pituitary gland height-to-brain area ratio (P:B ratio) to allow comparison of different sized and aged horses. Thirty-two horses without pituitary pars inter-media dysfunction that underwent a contrast-enhanced computed tomographic (CT) examination were included in a cross-sectional study. On the CT images, the pituitary gland height was measured and the P:B ratio was calculated. These measurements were correlated to the si...
Cross-sectional study of the prevalence of and risk factors for hoof disorders in horses in The Netherlands.
Preventive veterinary medicine    February 24, 2017   Volume 140 53-59 doi: 10.1016/j.prevetmed.2017.02.013
Holzhauer M, Bremer R, Santman-Berends I, Smink O, Janssens I, Back W.Information is scarce on the prevalence of hoof disorders in horses. In this study, we examined the prevalence of and risk factors for hoof disorders in a population of horses in The Netherlands. In a group of 942 randomly selected horses, hoof health was scored during regular foot trimming (one horse/farm). Hooves were assessed for the occurrence of one of 12 hoof disorders by a group of 21 certified farriers in two periods i.e. winter and summer of 2015. The mean age of the group of horses was 11.2±5.6years. They were mainly used for recreation (28.2%), dressage (26.8%), other disciplines (...
The relationship between mitochondrial DNA copy number and stallion sperm function.
Theriogenology    February 21, 2017   Volume 94 94-99 doi: 10.1016/j.theriogenology.2017.02.015
Darr CR, Moraes LE, Connon RE, Love CC, Teague S, Varner DD, Meyers SA.Mitochondrial DNA (mtDNA) copy number has been utilized as a measure of sperm quality in several species including mice, dogs, and humans, and has been suggested as a potential biomarker of fertility in stallion sperm. The results of the present study extend this recent discovery using sperm samples from American Quarter Horse stallions of varying age. By determining copy number of three mitochondrial genes, cytochrome b (CYTB), NADH dehydrogenase 1 (ND1) and NADH dehydrogenase 4 (ND4), instead of a single gene, we demonstrate an improved understanding of mtDNA fate in stallion sperm mitochond...
Encysted cyathostomin larvae in foals – progression of stages and the effect of seasonality.
Veterinary parasitology    February 20, 2017   Volume 236 108-112 doi: 10.1016/j.vetpar.2017.02.013
Nielsen MK, Lyons ET.Cyathostomins (small strongyles) are ubiquitous in grazing horses and are known pathogens as cause of larval cyathostominosis. As part of their life cycle, cyathostomin larvae invade the mucosal walls of the large intestines and undergo encystment. Newly ingested third stage larvae are known to undergo arrested development and this can lead to an accumulation of encysted burdens over the course of a grazing season. It is believed that the host immune system plays a significant role in triggering this arrestment. Little is known about the development and progression of larval stages in foals th...
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