References

Aleman M, Gray L, Williams D Juvenile idiopathic epilepsy in Egyptian Arabian foals: 22 Cases (1985-2005). J Vet Intern Med. 2006; 20:(6)1443-1449 https://doi.org/10.1892/0891-6640(2006)20[1443:jieiea]2.0.co;2

Bayir H, Adelson P, Wisniewski S Therapeutic hypothermia preserves anti-oxidant defenses after severe traumatic brain injury in infants and children. Crit Care Med. 2009; 37:(2)689-695 https://doi.org/10.1097/CCM.0b013e318194abf2

Beyer M, Freestone J, Reimer J Idiopathic hypocalcemia in foals. J Vet Intern Med. 1997; 11:(6)356-360 https://doi.org/10.1111/j.1939-1676.1997.tb00480.x

Brault LS, Famula T, Penedo M. Inheritance of cerebellar abiotrophy in Arabians. Am J Vet Res. 2011; 72:(7)940-944 https://doi.org/10.2460/ajvr.72.7.940

Brault L, Penedo M. The frequency of the equine cerebellar abiotrophy mutation in non-Arabian horse breeds. Equine Vet J. 2011; 43:(6)727-731 https://doi.org/10.1111/j.2042-3306.2010.00349.x

Broux B, Lefère L, Deprez P, van Loon G. Plasma exchange as a treatment for hyperbilirubinemia in 2 foals with neonatal isoerythrolysis. J Vet Intern Med. 2015; 29:(2)736-738 https://doi.org/10.1111/jvim.12549

Bugno-Poniewierska M, Stefaniuk-Szmukier M, Kajtoch A Genetic screening for cerebellar abiotrophy, severe combined immunodeficiency and lavender foal syndrome in Arabian horses in Poland. Vet J. 2019; 248:71-73 https://doi.org/10.1016/j.tvjl.2019.04.012

Chaudhry N, Duggal A. Sepsis-associated encephalopathy. Adv Med. 2014; 2014:1-16 https://doi.org/10.1155/2014/762320

Chaudhuri A. Adjunctive dexamethasone treatment in acute bacterial meningitis. Lancet Neurol. 2004; 3:(1)54-62 https://doi.org/10.1016/S1474-4422(03)00623-9

Cook T, Protheroe R, Handel J. Tetanus: a review of the literature. Br J Anaesth. 2001; 87:(3)477-487 https://doi.org/10.1093/bja/87.3.477

Corley K. A neurological score for hospitalized neonatal foals. J Vet Emerg Crit Care (San Antonio). 2004; 14:(S1)S1-S17 https://doi.org/10.1111/j.1476-4431.2004.t01-38-04035.x

Corley K, Hollis A. Antimicrobial therapy in neonatal foals. Equine Vet Educ. 2009; 01:(8)436-448 https://doi.org/10.2746/095777309X445352

Costa L, Donelly C, Crowe C Electroencephalographic alterations in a mare with presumed intermittent neuroglycopenia caused by severe hypoglycaemia-associated with nonislet cell tumour. Equine Vet Educ. 2020; 32:(5)238-245 https://doi.org/10.1111/eve.12947

Effect of intravenous corticosteroids on death within 14 days in 10,008 adults with clinically significant head injury (MRC CRASH trial): randomised placebo-controlled trial. The Lancet. 2004; 364:(9442)1321-1328 https://doi.org/10.1016/S0140-6736(04)17188-2

Dunkel B, Chaney K, Dallap-Schaer B Putative intestinal hyperammonaemia in horses: 36 cases. Equine Vet J. 2011; 43:(2)133-140 https://doi.org/10.1111/j.2042-3306.2010.00128.x

Dunkel B, Dodson F, Chang Y-M Retrospective evaluation of the association between hyponatremia and neurological dysfunction in hospitalized foals (2012-2016): 109 cases. J Vet Emerg Crit Care (San Antonio). 2020; 30:(1)66-73 https://doi.org/10.1111/vec.12906

Eberstein A, Eberstein S. Electrical stimulation of denervated muscle: is it worth-while?. Med Sci Sports Exerc. 1996; 28:(12)1463-9

Feldman Z, Kanter M, Robertson C Effect of head elevation on intracranial pressure, cerebral perfusion pressure, and cerebral blood flow in head-injured patients. J Neurosurg. 1992; 76:(2)207-211 https://doi.org/10.3171/jns.1992.76.2.0207

Finding E, McSloy A. Neonatal isoerythrolysis and other immunological diseases of foals. UK-Vet Compan Anim. 2011; 16:(3)10-12 https://doi.org/10.1111/j.2044-3862.2010.00047.x

Gofton TE, Young GB. Sepsis-associated encephalopathy. Nat Rev Neurol. 2012; 8:(10)557-566 https://doi.org/10.1038/nrneurol.2012.183

Hollis A, Furr M, Magdesian K Blood glucose concentrations in critically ill neonatal foals. J Vet Intern Med. 2008; 22:(5)1223-1227 https://doi.org/10.1111/j.1939-1676.2008.0174.x

Jaremko J, Moon A, Kumbla S. Patterns of complications of neonatal and infant meningitis on MRI by organism: a 10 year review. Eur J Radiol. 2011; 80:821-827 https://doi.org/10.1016/j.ejrad.2010.10.017

Jeremitsky E, Omert L, Dunham C The impact of hyperglycemia on patients with severe brain injury. J Trauma. 2005; 58:(1)47-50 https://doi.org/10.1097/01.ta.0000135158.42242.b1

Johnson A, Gilsenan W, Palmer J. Metabolic encephalopathies in foals - pay attention to the serum biochemistry panel!. Equine Vet Educ. 2012; 24:(5)233-235 https://doi.org/10.1111/j.2042-3292.2012.00396.x

Johnson A, Mcadams S, Whitlock R. Type A botulism in horses in the United States: a review of the past ten years (1998-2008). J Vet Diagn Invest. 2010; 22:(2)165-73 https://doi.org/10.1177/104063871002200201

Johnson P. Hypoglycaemia, hypoglycorrhachia, neuroglycopenia and glycaemic thresholds. Equine Veterinary Education. 2020; 32:(5)246-249 https://doi.org/10.1111/eve.13003

Koterba A, Brewer B, Tarplee F. Clinical and clinicopathological characteristics of the septicaemi neonatal foal: Review of 38 cases. Equine Vet J. 1984; 16:(4)376-382 https://doi.org/10.1111/j.2042-3306.1984.tb01950.x

Lakritz J, Madigan J, Carlson G. Hypovolemic hyponatremia and signs of neurologic disease associated with diarrhea in a foal. J Am Vet Med Assoc. 1992; 200:(8)1114-1116

Loynachan A, Williams N, Freestone J. Kernicterus in a neonatal foal. J Vet Diagn Invest. 2007; 19:(2)209-12 https://doi.org/10.1177/104063870701900215

MacKay R. Neurologic disorders of neonatal foals. Vet Clin North Am Equine Pract. 2005; 21:(2)387-406 https://doi.org/10.1016/j.cveq.2005.04.006

Mackenzie C, Haggett E, Powell S Traumatic sacral fracture following dystocia in a Thoroughbred foal. Equine Vet Educ. 2018; 30:518-521

Mayhew I, Watson A, Heissan J. Congenital occipitoatlantoaxial malformations in the horse. Equine Vet J. 1978; 10:(2)103-113 https://doi.org/10.1111/j.2042-3306.1978.tb02232.x

McConnico R, Duckett W, Wood P. Persistent hyperammonemia in two related Morgan Weanlings. J Vet Intern Med. 1997; 1:(4)264-266 https://doi.org/10.1111/j.1939-1676.1997.tb00101.x

Mitchell E, Furr M, Mckenzie H. Bacterial meningitis in five mature horses. Equine Vet Educ. 2006; 18:249-255 https://doi.org/10.1111/j.2042-3292.2006.tb00457.x

Mitchell E, Furr M, McKenzie H. Antimicrobial therapy for bacterial meningitis. Equine Vet Educ. 2007; 19:316-323 https://doi.org/10.2746/095777307X207105

Morresey P, Garrett K, Carter D. Rhodococcus equi occipital bone osteomyelitis, septic arthritis and meningitis in a neurological foal. Equine Vet Educ. 2010; 23:398-402 https://doi.org/10.1111/j.2042-3292.2010.00119.x

Mykkänen A, Hyytiäinen H, McGowan C. Generalised tetanus in a 2-week-old foal: Use of physiotherapy to aid recovery. Aus Vet J. 2011; 89:(11)447-451 https://doi.org/10.1111/j.1751-0813.2011.00845.x

Oey L, Müller J, Klopmann T Diagnosis of internal and external hydrocephalus in a warmblood foal using magnetic resonance imaging. Tierärztliche Praxis Ausgabe G, Grosstiere/Nutztiere. 2011; 39:41-45 https://doi.org/10.1055/s-0038-1624609

Ogunlesi T, Odigwe C, Oladapo O. Adjuvant corticosteroids for reducing death in neonatal bacterial meningitis. Cochrane Database Syst Rev. 2015; 11 https://doi.org/10.1002/14651858.CD010435.pub2

Prutton J, Magdesian K, Plummer A Survival of a foal with type A botulism. J Vet Intern Med. 2016; 30:(2)675-678 https://doi.org/10.1111/jvim.13840

Reed S, Bayly W, Sellon D. Equine Internal Medicine, 4th edn. In: McKenzie H (ed). USA: Elsevier; 2016

Sanchez L, Giguère S, Lester G. Factors associated with survival of neonatal foals with bacteremia and racing performance of surviving Thoroughbreds: 423 cases (1982–2007). J Am Vet Med Assoc. 2008; 233:(9)1446-1452 https://doi.org/10.2460/javma.233.9.1446

Schwarz B, van den Hoven R. Seizures in an Arabian foal due to suspected prolonged transient neonatal hypoparathyroidism. Equine Vet Educ. 2012; 24:(5)225-232 https://doi.org/10.1111/j.2042-3292.2011.00268.x

Sipma K, Cornillie P, Saulez M Phenotypic characteristics of hydrocephalus in stillborn friesian foals. Vet Pathol. 2013; 50:(6)1037-1042 https://doi.org/10.1177/030098581348895

Stratford C, Mayhew I, Hudson N. Equine botulism: a clinical approach to diagnosis and management. Equine Vet Educ. 2014; 26:(8)441-448 https://doi.org/10.1111/eve.12198

Tarr C, Thompson P, Guthrie A The carrier prevalence of severe combined immunodeficiency, lavender foal syndrome and cerebellar abiotrophy in Arabian horses in South Africa. Equine Vet J. 2014; 46:(4)512-514 https://doi.org/10.1111/evj.12177

Trefz F, Feist M, Lorenz I. Hypoglycaemia in hospitalised neonatal calves: prevalence, associated conditions and impact on prognosis. The Vet J. 2016; 217:103-108 https://doi.org/10.1016/j.tvjl.2016.10.001

Verbalis J, Goldsmith S, Greenberg A Diagnosis, evaluation, and treatment of hyponatremia: expert panel recommendations. Am J Med. 2013; 126:(10)S1-S42 https://doi.org/10.1016/j.amjmed.2013.07.006

Viu J, Armengou L, de la Fuente C Magnetic resonance imaging of bacterial meningoencephalitis in a foal. Case Rep Vet Med. 2012a; https://doi.org/10.1155/2012/402714

Viu J, Monreal L, Jose-Cunilleras E Clinical findings in 10 foals with bacterial meningoencephalitis. Equine Vet J. 2012b; 44:(S41)100-104 https://doi.org/10.1111/j.2042-3306.2011.00508.x

Wilkins P, Palmer J. Botulism in foals less than 6 months of age: 30 cases (1989-2002). J Vet Intern Med. 2003; 17:(5)702-707 https://doi.org/10.1111/j.1939-1676.2003.tb02503.x

Zhang QH, Sheng Z-Y, Yao Y. Septic encephalopathy: when cytokines interact with acetylcholine in the brain. Military Med Res. 2014; 1 https://doi.org/10.1186/2054-9369-1-20

Neurological disease in neonatal foals: beyond dummy foal syndrome

02 January 2022
17 mins read
Volume 6 · Issue 1
Figure 4. A foal with a head tilt following head trauma. A subpalpebral lavage system is present in the left upper eyelid for management of a corneal ulcer.
Figure 4. A foal with a head tilt following head trauma. A subpalpebral lavage system is present in the left upper eyelid for management of a corneal ulcer.

Abstract

Neonatal encephalopathy (dummy foal syndrome) is the most common cause of neurological signs in neonatal foals. However, there are a wide variety of other causes that may be overlooked, including infections, traumatic, metabolic and congenital causes. There is much overlap between the clinical signs for many of these conditions, highlighting the need for thorough history taking, physical examination, laboratory testing and, in some cases, diagnostic imaging. In most cases, prompt treatment is required if there is to be any chance of survival, further highlighting the need for an accurate diagnosis. The prognosis of these conditions varies from rapidly correctable with appropriate treatment, to euthanasia being the only humane option.

Weakness and abnormal behaviour are common presenting clinical signs in unwell neonatal foals. This may be the result of a primary neurological disorder, or numerous other conditions. Acquiring a thorough history, including events during gestation, foaling and post-foaling, as well as investigating all body systems, is warranted for any case.

Neonatal encephalopathy (dummy foal syndrome) is a condition that equine veterinarians who see foals will be familiar with. Dummy foal syndrome generally affects foals in the first 48–72 hours of life (although it can be up to 7 days before clinical signs develop) and causes a range of neurological clinical signs from loss of affinity to the mare, to grand mal seizures. Dummy foal disease was extensievly covered in the Novemeber 2020 issue of UK-Vet Equine, so this review focuses on the other neurological conditions that can cause clinical signs in neonatal foals (Table 1). For the purpose of this review, neonatal foals less than 30 days of age will be considered.

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