Analyze Diet

Topic:Ponies

Ponies are members of the Equus genus, distinguished primarily by differences in size, build, and certain physiological traits. Horses are typically larger, with a height at the withers exceeding 14.2 hands (58 inches), while ponies measure 14.2 hands or shorter. These distinctions are not solely based on size; ponies often exhibit thicker manes, tails, and overall sturdier builds. Despite these differences, both ponies and horses share similar dietary needs, social behaviors, and reproductive processes. This page compiles peer-reviewed research studies and scholarly articles that explore the anatomical, genetic, and behavioral aspects of ponies and horses, as well as their roles in various human activities and environments.
A pressure plate study on fore and hindlimb loading and the association with hoof contact area in sound ponies at the walk and trot.
Veterinary journal (London, England : 1997)    September 27, 2010   Volume 190, Issue 1 71-76 doi: 10.1016/j.tvjl.2010.08.016
Oosterlinck M, Pille F, Back W, Dewulf J, Gasthuys F.The aim of this study was to evaluate the association between fore- and hind-hoof contact area and limb loading. Data from a previous study on forelimb loading and symmetry were compared with data on hindlimb kinetics, and the fore- and hind-hoof contact area at the walk and trot was evaluated. Five sound ponies, selected for symmetrical feet, were walked and trotted over a pressure plate embedded in a custom-made runway. The hindlimb peak vertical force (PVF) and vertical impulse (VI) were found to be significantly lower than in the forelimb, whereas their high symmetry ratios (>95%) did n...
Field treatment and management of endocrinopathic laminitis in horses and ponies.
The Veterinary clinics of North America. Equine practice    August 12, 2010   Volume 26, Issue 2 379-390 doi: 10.1016/j.cveq.2010.05.001
Walsh DM.Endocrinopathic laminitis in horses and ponies has the potential to cause extensive damage to the feet before clinical signs of laminitis are apparent. Early diagnosis and intervention based on the detection and control of hyperinsulinemia are critical if the crippling changes that are seen in the disease are to be avoided. Preventing endocrinopathic laminitis, rather than treating it, is good practice management benefiting not only equine patients but also their owners.
Cardiopulmonary effects of two constant rate infusions of dexmedetomidine in isoflurane anaesthetized ponies.
Veterinary anaesthesia and analgesia    July 20, 2010   Volume 37, Issue 4 311-321 doi: 10.1111/j.1467-2995.2010.00537.x
Marcilla MG, Schauvliege S, Duchateau L, Gasthuys F.To evaluate the cardiopulmonary effects of two different constant rate infusions (CRI) of dexmedetomidine (1 and 1.75 microg kg(-1 )hour(-1)) in experimental ponies. Methods: Six healthy ponies (mean 306 +/- SD 71 kg, 7.0 +/- 1.6 years). Methods: Prospective, randomized, experimental study. Methods: After premedication with intravenous (IV) dexmedetomidine (3.5 microg kg(-1)), anaesthesia was induced (T0) with ketamine (2.2 mg kg(-1) IV) and midazolam (0.06 mg kg(-1) IV) and maintained with isoflurane (Fe'ISO 1.50%) in 55% oxygen for 150 minutes. Normocapnia was maintained using artificial ven...
Laminitis and the equine metabolic syndrome.
The Veterinary clinics of North America. Equine practice    June 9, 2010   Volume 26, Issue 2 239-255 doi: 10.1016/j.cveq.2010.04.004
Johnson PJ, Wiedmeyer CE, LaCarrubba A, Ganjam VK, Messer NT.Although much has been written about laminitis in the context of its association with inflammatory processes, recognition is growing that most cases of laminitis examined by veterinarians in private practice are those associated with pasture grazing, obesity, and insulin resistance (IR). The term 'endocrinopathic laminitis' has been adopted to classify the instances of laminitis in which the origin seems to be more strongly associated with an underlying endocrinopathy, such as either IR or the influence of corticosteroids. Results of a recent study suggest that obesity and IR represent the mos...
Equine laminitis: ultrastructural lesions detected in ponies following hyperinsulinaemia.
Equine veterinary journal    November 26, 2009   Volume 41, Issue 7 671-677 doi: 10.2746/042516409x407648
Nourian AR, Asplin KE, McGowan CM, Sillence MN, Pollitt CC.Anatomical changes in the hoof lamellar tissue induced by prolonged hyperinsulinaemia have not been described previously. Analysis of the induced lesions may promote understanding of hyperinsulinaemic laminitis pathogenesis and produce clinical benefit. Objective: To use light and transmission electron microscopy (TEM) to document hoof lamellar lesions in ponies clinically lame after prolonged hyperinsulinaemia. Methods: Nine clinically normal, mature ponies were allocated randomly to either a treatment group (n = 5) or control group (n = 4). The treatment group received insulin via a modified...
Multiple oral dosing of valacyclovir in horses and ponies.
Journal of veterinary pharmacology and therapeutics    August 4, 2009   Volume 32, Issue 3 207-212 doi: 10.1111/j.1365-2885.2008.01025.x
Garré B, Baert K, Nauwynck H, Deprez P, De Backer P, Croubels S.The aim of the current study was to investigate whether multiple oral dosing of valacyclovir could result in plasma concentrations exceeding the EC(50)-value of acyclovir against equine herpesvirus 1 (EHV1) during the majority of the treatment period. Additionally, we wanted to determine the concentration of acyclovir in nasal mucus and cerebrospinal fluid (CSF). Valacyclovir was administered to four horses and two ponies, three times daily, at a dosage of 40 mg/kg, for four consecutive days. Blood was collected prior to each administration and 1 h after dosing. Nasal mucus samples and CSF wer...
Synthesis and detection of toltrazuril sulfone and its pharmacokinetics in horses following administration in dimethylsulfoxide.
Journal of veterinary pharmacology and therapeutics    July 21, 2009   Volume 32, Issue 4 368-378 doi: 10.1111/j.1365-2885.2008.01053.x
Dirikolu L, Karpiesiuk W, Lehner AF, Hughes C, Granstrom DE, Tobin T.Triazine-based antiprotozoal agents are known for their lipophylic characteristics and may therefore be expected to be well absorbed following oral administration. However, although an increase in lipid solubility generally increases the absorption of chemicals, extremely lipid-soluble chemicals may dissolve poorly in gastrointestinal (GI) fluids, and their corresponding absorption and bioavailability would be low. Also, if the compound is administered in solid form and is relatively insoluble in GI fluids, it is likely to have limited contact with the GI mucosa, and therefore, its rate of abs...
Effects of dobutamine on cardiovascular function and respiratory gas exchange after enoximone in isoflurane-anaesthetized ponies.
Veterinary anaesthesia and analgesia    June 16, 2009   Volume 35, Issue 4 306-318 doi: 10.1111/j.1467-2995.2007.00392.x
Schauvliege S, Van den Eede A, Duchateau L, Gasthuys F.To evaluate the combined effects of enoximone and dobutamine on the cardiovascular system and respiratory gas exchange in isoflurane-anaesthetized ponies. Methods: Prospective, randomized, experimental study. Methods: Six ponies (286 +/- 52 kg), aged 5.0 +/- 1.6 years. Methods: After sedation (romifidine 80 microg kg(-1)), anaesthesia was induced with midazolam (0.06 mg kg(-1)) and ketamine (2.2 mg kg(-1)) and maintained with isoflurane in oxygen. The ponies were ventilated to maintain eucapnia. After 90 minutes (=T0), enoximone alone (0.5 mg kg(-1)) (E) or enoximone, followed by a constant ra...
Combining microsatellite and pedigree data to estimate relationships among Skyros ponies.
Journal of applied genetics    May 13, 2009   Volume 50, Issue 2 133-143 doi: 10.1007/BF03195664
Bomcke E, Gengler N.Relationship coefficients are particularly useful to improve genetic management of endangered populations. These coefficients are traditionally based on pedigree data, but in case of incomplete or inexistent pedigrees they are replaced by coefficients calculated from molecular data. The main objective of this study was to develop a new method to estimate relationship coefficients by combining molecular with pedigree data, which is useful for specific situations where neither pedigree nor molecular data are complete. The developed method was applied to contribute to the conservation of the Skyr...
Characterization of hypertriglyceridemia and response to treatment with insulin in horses, ponies, and donkeys: 44 cases (1995-2005).
Journal of the American Veterinary Medical Association    April 2, 2009   Volume 234, Issue 7 915-919 doi: 10.2460/javma.234.7.915
Waitt LH, Cebra CK.To characterize signalment, clinical signs of disease, and clinical response to insulin in equids with hypertriglyceridemia. Methods: Retrospective case series. Methods: 20 horses, 17 ponies, and 7 donkeys with hypertriglyceridemia. Methods: For analysis of medical record data, horses, donkeys, and ponies with multiple serum or plasma triglycerides measurements were separated into groups. Hypertriglyceridemic equids that were (HT-I; n = 14) or were not (HT-N; 10) treated with insulin consisted of equids with an initial triglycerides concentration > 44 mg/dL but < 500 mg/dL. Equids with an init...
Influence of calcium chloride on the cardio-respiratory effects of a bolus of enoximone in isoflurane anaesthetized ponies.
Veterinary anaesthesia and analgesia    February 26, 2009   Volume 36, Issue 2 101-109 doi: 10.1111/j.1467-2995.2008.00435.x
Schauvliege S, Van den Eede A, Duchateau L, Pille F, Vlaminck L, Gasthuys F.To investigate the influence of calcium chloride (CaCl(2)) on the cardio-respiratory effects of enoximone in isoflurane anaesthetized ponies. Methods: Prospective consecutive experimental trial. Animals Six healthy ponies, weighing 287 +/- 55 kg were included in this study. Methods: After sedation (romifidine, 80 microg kg(-1)), anaesthesia was induced with midazolam (0.06 mg kg(-1)) and ketamine (2.2 mg kg(-1)) and maintained with isoflurane in oxygen. The ponies' lungs were ventilated to maintain normocapnia. After 90 minutes, a bolus of enoximone (0.5 mg kg(-1)) was administered, followed b...
Use of a stand-alone pressure plate for the objective evaluation of forelimb symmetry in sound ponies at walk and trot.
Veterinary journal (London, England : 1997)    February 13, 2009   Volume 183, Issue 3 305-309 doi: 10.1016/j.tvjl.2008.12.012
Oosterlinck M, Pille F, Back W, Dewulf J, Gasthuys F.Subtle lameness in horses may be difficult to diagnose and methods to evaluate lameness objectively are useful when equine clinicians fail to reach a consensus. The aim of this study was to determine whether equine pressure plate measurements are repeatable when used to calculate forelimb loading (peak vertical pressure [PVP], peak vertical force [PVF], vertical impulse [VI]) and symmetry ratios, and to establish if these data are similar to the 'gold standard' force plate values. Since plate dimensions are relatively small, ponies were used to enable recordings to be taken from both forelimbs...
Evaluation of orally administered valacyclovir in experimentally EHV1-infected ponies.
Veterinary microbiology    September 21, 2008   Volume 135, Issue 3-4 214-221 doi: 10.1016/j.vetmic.2008.09.062
Garré B, Gryspeerdt A, Croubels S, De Backer P, Nauwynck H.The purpose of the current study was to investigate the therapeutic efficacy of valacyclovir against EHV1 in a controlled study. Eight naïve Shetland ponies were inoculated with 10(6.5) TCID(50) of the neuropathogenic strain 03P37. Four ponies were treated with valacyclovir at a dosage of 40mg/kg bodyweight, 3 times daily, for 5 (n=2) or 7 (n=2) consecutive days, while the other four ponies served as untreated controls. The treatment regimen started 1h before inoculation. Ponies were monitored daily for clinical signs. At 0, 1, 2, 3, 4, 5, 7, 9, 11, 14, 17 and 21 days post inoculation (d pi),...
The effect of metformin on measurements of insulin sensitivity and beta cell response in 18 horses and ponies with insulin resistance.
Equine veterinary journal    May 17, 2008   Volume 40, Issue 5 493-500 doi: 10.2746/042516408X273648
Durham AE, Rendle DI, Newton JE.Laminitis in equids is a very common debilitating disease, and insulin resistance (IR) and hyperinsulinaemia are increasingly recognised as important predisposing factors. Pharmacological modification of IR and hyperinsulinaemia might reduce the risk of laminitis. Objective: Metformin, a drug commonly prescribed for treatment of human IR, may also decrease IR in equids. Methods: Eighteen horses and ponies with IR and recurrent laminitis were treated with 15 mg/kg bwt metformin per os q. 12 h. Each animal served as its own control by comparing pre- and post treatment proxies for IR, insulin sen...
The influence of body mass and thoracic dimensions on arterial oxygenation in anaesthetized horses and ponies.
Veterinary anaesthesia and analgesia    May 5, 2008   Volume 35, Issue 5 392-399 doi: 10.1111/j.1467-2995.2008.00400.x
Mansel JC, Clutton RE.To examine the relationship between body mass and thoracic dimensions on arterial oxygen tensions (PaO(2)) in anaesthetized horses and ponies positioned in dorsal recumbency. Methods: Prospective clinical study. Methods: Thirty six client-owned horses and ponies, mean [+/-SD (range)] age 8.1 +/- 4.8 (1.5-20) years and mean body mass 467 +/- 115 (203-656) kg. Methods: Before general anaesthesia, food and water were withheld for 12 and 1 hours respectively. Body mass (kg), height at the withers (H), thoracic circumference (C), thoracic depth (length between dorsal spinous process and sternum; D)...
Effects of a low dose infusion of racemic and S-ketamine on the nociceptive withdrawal reflex in standing ponies.
Veterinary anaesthesia and analgesia    May 5, 2008   Volume 35, Issue 5 414-423 doi: 10.1111/j.1467-2995.2008.00402.x
Peterbauer C, Larenza PM, Knobloch M, Theurillat R, Thormann W, Mevissen M, Spadavecchia C.To investigate the effect of plasma concentrations obtained by a low dose constant rate infusion (CRI) of racemic ketamine or S-ketamine on the nociceptive withdrawal reflex (NWR) in standing ponies. Methods: Prospective, blinded, cross-over study. Methods: Six healthy 5-year-old Shetland ponies. Methods: Ponies received either 0.6 mg kg(-1) racemic ketamine (group RS) or 0.3 mg kg(-1) S-ketamine (group S) intravenously (IV), followed by a CRI of 20 microg kg(-1)minute(-1) racemic ketamine (group RS) or 10 microg kg(-1)minute(-1) S-ketamine (group S) for 59 minutes. The NWR was evoked by trans...
Characterization of clinically-attenuated Burkholderia mallei by whole genome sequencing: candidate strain for exclusion from Select Agent lists.
PloS one    April 30, 2008   Volume 3, Issue 4 e2058 doi: 10.1371/journal.pone.0002058
Schutzer SE, Schlater LR, Ronning CM, DeShazer D, Luft BJ, Dunn JJ, Ravel J, Fraser-Liggett CM, Nierman WC.Burkholderia mallei is an understudied biothreat agent responsible for glanders which can be lethal in humans and animals. Research with this pathogen has been hampered in part by constraints of Select Agent regulations for safety reasons. Whole genomic sequencing (WGS) is an apt approach to characterize newly discovered or poorly understood microbial pathogens. Results: We performed WGS on a strain of B. mallei, SAVP1, previously pathogenic, that was experimentally infected in 6 equids (4 ponies, 1 mule, 1 donkey), natural hosts, for purposes of producing antibodies. Multiple high inocula wer...
Comparison of radiofrequency treatment and mechanical debridement of fibrillated cartilage in an equine model.
Veterinary and comparative orthopaedics and traumatology : V.C.O.T    February 22, 2008   Volume 21, Issue 1 41-48 doi: 10.3415/VCOT-07-01-0004
Edwards RB, Lu Y, Cole BJ, Muir P, Markel MD.To compare a radiofrequency energy (RFE) prototype probe to mechanical debridement (MD) and a commercially available RFE system used for chondroplasty in the treatment of an experimentally created partial thickness cartilage lesion in horses. The study design was experimental, randomized complete block, n=8, using fifteen mature ponies. Methods: Grade 2 to 3 cartilage lesions were prepared in both patellae. After 10 months duration, the injuries were used to study the effects of MD, a commercially available bipolar RFE device (CoVac 50; ArthroCare Corporation) and a prototype monopolar RFE dev...
Anesthesia in Caspian ponies.
Veterinary anaesthesia and analgesia    October 10, 2007   Volume 35, Issue 3 237-241 doi: 10.1111/j.1467-2995.2007.00366.x
Seddighi MR, Mohri M.To evaluate some of the clinical and laboratory parameters following diazepam-acepromazine, thiopental, and halothane anesthesia in Caspian ponies. Methods: Prospective experimental trial. Methods: Six healthy Caspian ponies of both sexes, aged 11 +/- 3 years and weighing 318 +/- 71 kg. Methods: The ponies were pre-medicated with diazepam (0.2 mg kg(-1)) and acepromazine (0.05 mg kg(-1)) IV. Sodium thiopental 5% was administered IV, 10 minutes later and anesthesia was maintained with halothane in oxygen for 1 hour. Heart and respiratory rates, mean arterial blood pressure, cardiac rhythm, and ...
In vivo study on the short-term effect of radiofrequency energy on chondromalacic patellar cartilage and its correlation with calcified cartilage pathology in an equine model.
Journal of orthopaedic research : official publication of the Orthopaedic Research Society    March 4, 2006   Volume 24, Issue 4 716-724 doi: 10.1002/jor.20108
Uthamanthil RK, Edwards RB, Lu Y, Manley PA, Athanasiou KA, Markel MD.Chondromalacia can cause joint pain and synovial effusion with the potential for developing into osteoarthritis. Thermal chondroplasty using radiofrequency energy (RFE) has been reported to be superior to mechanical debridement for treating chondromalacia. We compared short-term changes in biomechanical properties of articular cartilage after treatment with monopolar (mRFE) or bipolar RFE (bRFE) or mechanical debridement (MD) on experimentally created grade II chondromalacia patellae. Chondromalacia patellae was created arthroscopically in both patellae of 15 ponies. Ten months after surgery, ...
Clinical application of parenteral nutrition in the treatment of five ponies and one donkey with hyperlipaemia.
The Veterinary record    February 8, 2006   Volume 158, Issue 5 159-164 doi: 10.1136/vr.158.5.159
Durham AE.Five ponies and one donkey with hyperlipaemia that occurred secondarily to a variety of primary clinical conditions were treated with lipid-free partial parenteral nutrition comprising equal volumes of 50 per cent glucose and 15 per cent amino acids. The infusion supplied energy and protein at rates of 2.6 kJ/kg per hour and 34.3 mg/kg per hour, respectively. In all six cases there was a prompt and sustained decrease in serum concentrations of triglyceride. In four of the six cases a good response to treatment of the primary condition was also seen and the subjects were discharged successfully...
A comparison of the effect of forage type and level of feeding on the digestibility and gastrointestinal mean retention time of dry forages given to cattle, sheep, ponies and donkeys.
The British journal of nutrition    January 31, 2006   Volume 95, Issue 1 88-98 doi: 10.1079/bjn20051617
Pearson RA, Archibald RF, Muirhead RH.Four cattle, sheep, ponies and donkeys were fed dehydrated lucerne, early-cut hay, later-cut hay or barley straw in a Latin square-based design for four periods of 35 d. In the first sub-period animals were fed the diets ad libitum (1-21 d) and in the second sub-period they were fed the same diet restricted to 0.75 of ad libitum intake (days 22-35). Measurements of forage intake, apparent digestibilities and gastrointestinal mean retention times (MRT) were made in the last 7 d of each sub-period. Differences between species in voluntary DM intake (VDMI; g/kg live weight (LW)(0.75) and g/LW) we...
A study of seven different types of grafts for jugular vein transplantation in the horse.
Research in veterinary science    May 17, 2005   Volume 79, Issue 3 211-217 doi: 10.1016/j.rvsc.2004.12.005
Wiemer P, Gruys E, van Hoeck B.The aim of this study was to investigate the biological behaviour of vascular grafts replacing a section of the jugular vein in order to improve the results of the surgical treatment of complete thrombosis of the jugular vein in the horse. Seven graft types: fresh allograft, home frozen allograft, glutaraldehyde-fixed allograft, cryo-preserved allograft, PTFE-graft (Gore), small intestinal submucosa preparation (Cook) and fresh autograft, were randomly implanted in ponies. The grafts were removed after one month and examined histologically for: preservation of the graft structures, acceptance ...
Changes to oxfendazole chiral kinetics and anthelmintic efficacy induced by piperonyl butoxide in horses.
Equine veterinary journal    May 17, 2005   Volume 37, Issue 3 257-262 doi: 10.2746/0425164054530669
Sánchez Bruni SF, Fusé LA, Moreno L, Saumell CA, Alvarez LI, Fiel C, McKellar QA, Lanusse CE.The study of novel pharmacological strategies to control parasitism in horses is required since many parasite species have developed resistance to anthelmintic drugs. Objective: To evaluate the effects of piperonyl butoxide (PB) (a metabolic inhibitor) on the plasma availability and enantiomeric behaviour of oxfendazole (OFZ) given orally to horses, and to compare the clinical efficacy of OFZ given either alone or co-administered with PB in naturally parasitised horses. Methods: Fifteen naturally parasitised crossbred male ponies were allocated into 3 groups (n = 5) and treated orally as follo...
Antibiotic treatment of experimentally Borrelia burgdorferi-infected ponies.
Veterinary microbiology    May 3, 2005   Volume 107, Issue 3-4 285-294 doi: 10.1016/j.vetmic.2005.02.006
Chang YF, Ku YW, Chang CF, Chang CD, McDonough SP, Divers T, Pough M, Torres A.The objective of this study is to determine whether doxycycline, ceftiofur or tetracycline could be effectively used to treat equine Lyme disease. Ponies experimentally infected with Borrelia burgdorferi by tick exposure were treated with doxycycline, ceftiofur or tetracycline for 4 weeks (28 days). Doxycyline and ceftiofur treatment were inconsistent in eliminating persistent infection in this experimental model. However, tetracycline treatment seems to eliminate persistent infection. Although serum antibody levels to B. burgdorferi in all ponies declined gradually after antibiotic treatment,...
Efficacy of a recombinant equine influenza vaccine against challenge with an American lineage H3N8 influenza virus responsible for the 2003 outbreak in the United Kingdom.
The Veterinary record    April 9, 2005   Volume 156, Issue 12 367-371 doi: 10.1136/vr.156.12.367
Edlund Toulemonde C, Daly J, Sindle T, Guigal PM, Audonnet JC, Minke JM.Fifteen influenza-naive Welsh mountain ponies were randomly assigned to three groups of five. A single dose of a recombinant ALVAC vaccine was administered intramuscularly to five of the ponies, two doses, administered five weeks apart, were administered to five, and the other five served as unvaccinated, challenge controls. Two weeks after the completion of the vaccination programme, the ponies were all challenged by exposure to an aerosol of influenza virus A/eq/Newmarket/5/03. Their clinical signs were scored daily for 14 days according to a standardised scoring protocol, and nasal swabs we...
Comparison of nonspecific indications and quantitative methods for the assessment of insulin resistance in horses and ponies.
Journal of the American Veterinary Medical Association    March 22, 2005   Volume 226, Issue 5 712-719 doi: 10.2460/javma.2005.226.712
Kronfeld DS, Treiber KH, Geor RJ.No abstract available
Evaluation of pituitary gland anatomy and histopathologic findings in clinically normal horses and horses and ponies with pituitary pars intermedia adenoma.
American journal of veterinary research    January 6, 2005   Volume 65, Issue 12 1701-1707 doi: 10.2460/ajvr.2004.65.1701
van der Kolk JH, Heinrichs M, van Amerongen JD, Stooker RC, in de Wal LJ, van den Ingh TS.To determine size and weight of the pituitary gland and associations between pituitary gland size and weight and sex and age in horses without clinical signs associated with pituitary pars intermedia adenoma (PPIA) and horses and ponies with PPIA. Methods: Pituitary glands from 100 horses without clinical signs of PPIA and 19 horses and 17 ponies with PPIA. Methods: Pituitary glands were weighed, measured, and examined histologically by use of H&E stain. Masson trichrome and periodic acid-Schiff staining were used, when appropriate. Histologic lesions in the pars intermedia, pars distalis,...
Quantitative motor unit action potential analysis in skeletal muscles in horses and ponies.
Veterinary research communications    September 18, 2004   Volume 28 Suppl 1 177-179 doi: 10.1023/b:verc.0000045400.72642.9d
Ciminaghi B, Albertini M, Costanzi M, Patrese F, Clement MG.No abstract available
Evidence supporting the inclusion of strains from each of the two co-circulating lineages of H3N8 equine influenza virus in vaccines.
Vaccine    September 15, 2004   Volume 22, Issue 29-30 4101-4109 doi: 10.1016/j.vaccine.2004.02.048
Daly JM, Yates PJ, Newton JR, Park A, Henley W, Wood JL, Davis-Poynter N, Mumford JA.Two lineages of antigenically distinct equine influenza A H3N8 subtype viruses, American and European, co-circulate. Experiments were conducted in ponies to investigate the protection induced by vaccines containing virus from one lineage against challenge infection with homologous or heterologous virus. Regression analysis showed that vaccinated ponies with average pre-challenge single radial haemolysis (SRH) antibody levels (i.e. 45-190mm2) had a higher probability of becoming infected if they were vaccinated with virus heterologous to the challenge strain than if they were vaccinated with ho...