Get access to all handy features included in the IVIS website
- Get unlimited access to books, proceedings and journals.
- Get access to a global catalogue of meetings, on-site and online courses, webinars and educational videos.
- Bookmark your favorite articles in My Library for future reading.
- Save future meetings and courses in My Calendar and My e-Learning.
- Ask authors questions and read what others have to say.
Management Approaches to the Newborn Foal Use of Risk Factors
Get access to all handy features included in the IVIS website
- Get unlimited access to books, proceedings and journals.
- Get access to a global catalogue of meetings, on-site and online courses, webinars and educational videos.
- Bookmark your favorite articles in My Library for future reading.
- Save future meetings and courses in My Calendar and My e-Learning.
- Ask authors questions and read what others have to say.
Read
Most foal deaths occur within the first week of life and often within the first 48 hrs.1,2 The leading causes of foal problems are bacterial infection, maladjustment, starvation, exposure and dystocia. Management methods aimed at prevention of these problems may make a difference. We should use the concept of risk factors for the foal to guide our level of intervention to optimize and accelerate the detection of problems in high risk foals. This also prevents us from over-evaluating the healthy foal.
It is important to realize that newborn foals with recently acquired infection look their best shortly following birth and may first show obvious signs of problems only after illness is well established3, unless problems are detected early, these foals may die or require expensive and long term therapy. Newborn foals with risk factors, including an unobserved birth in a unclean situation, should be evaluated more carefully and often need to be immediately placed on antibiotics pending further work up. (See Chapter 69)
The first 16 hrs. of life the neonatal gut is “open” for antibody absorption and bacteria may have enhanced opportunity for translocation and establishing bacteremia. Bacterial exposure occurs when the foal attempts to nurse (e.g., Coliforms on mare’s udder, environment, etc.) or has delayed nursing and the gut stays “open” longer. Antibiotics can prevent many infections when begun during the first 2-12 hrs. of life. If there are risk factors - don’t wait for the foal to show signs of illness.
Three Categories of Risk
Low-Risk Foals
- No maternal risk factors identified.
- Gestation of normal duration (Chapter 5).
- Events of parturition normal (Chapter 5).
- Stage 2 labor lasted less than 20 minutes.
- No significant manipulation of foal required for delivery.
- Foal stood by 2 hours.
- Foal nursed by 3 hours.
- Placenta visually normal and < 10% of the body weight of the foal.
- No environmental risk factors.
- Post foaling stress score normal (Chapter 5).
- Provide care as described for routine post foaling procedures (Chapter 7).
Moderate Risk Foals
These foals have only 1 risk factor of maternal or foal origin.
- Place foal on antibiotics immediately post birth for 48-72 hrs.
- Warrants a more frequent monitoring plan during the first week of life.
- Observe for early signs of illness (Chapter 25).
- Laboratory evaluation for these foals (may need to serially monitor over 1 week).
- Complete Blood Count
- Serum IgG - Repeat determination to see if IgG drops from rapid consumption.
- Blood chemistry profile with electrolytes.
- Body weight measured daily.
- Foals should gain 1-3 lbs (0.5-1.5 Kg) per day.
Remember to use specific reference values that are age-matched and specific for neonatal foals (Chapters 72 and 73)
High Risk Foals
Maternal Conditions3,4,5
- Concurrent illness or fever.
- Pharmacologic related.
- Sedation, tranquilizers, anesthetics may produce fetal depression.
- Nonsteroidal anti-inflammatory drugs.
- Beta-2 agonist bronchodilators may relax uterine smooth muscle.
- Excessive medication.
- In a recent study administration of altrenogest has not shown to alter the response to exogenous ACTH after birth although foals had significantly lower neutrophil/lymphocyte ratio6. - Colic, endotoxemia with or without surgery; endotoxin and bacteria may affect fetus.
- Vaginal discharge
Mucopurulent exudate. - Poor nutritional status.
- Twins.
Twins that go to term are at risk from malposition and delivery problems. - Chronic lameness or incoordination.
Inability of the mare to easily lie down and roll and rise so as to position foal may produce malposition. - Recent transport stress.
- Premature lactation (“dripping milk” before parturition) and loss of colostral proteins.
- Pelvic abnormalities from prior trauma or space-occupying lesions.
- Maternal hyperventilation4
Severe pain, prolonged parturition, chronic obstruction pulmonary distress. May cause maternal respiratory alkalosis and shift hemoglobin dissociation curve. Increased affinity of maternal hemoglobin for O2 may decrease transplacental O2 diffusion. - Prolonged gestation with oversized foal (rare).
- Cesarean section.
- Barbiturate anesthesia and halothane can produce fetal depression.
- Dorsal recumbency may compress uterine blood flow.
- Absence of factors that are associated with the initiation of respiration in vaginal delivery. - Agalactia.
- History of producing a neonatal isoerythrolysis foal.
- Poor mothering
Mild or complete foal rejection, extensive movements that cause foal weakness from the foal trying to follow the mare.
Placental Factors2,5
- Placentitis
- Vasculitis and edema from systemic disease.
- Vascular disturbances - thrombosis-infarction.
Conditions of Labor or Delivery3,4,7
- Any prolonged uterine contractions.
- Dystocia (Chapter 6)
Leads to placental separation and decreased uterine blood flow. Aspiration of amniotic fluid, bacteria-containing fluid, or meconium can produce pneumonia and respiratory distress at birth. - Partial or complete premature placental separation.
Seen as chorion protruding from vagina. Chorion has a red velvet appearance and precedes the foal during parturition. Produces foal anoxia during delivery. Correction by manual tearing of chorion and rapidly assisting delivery with immediate oxygen therapy and implementation of resuscitation protocol. (Chapter 16) - Medically induced labor.(Chapter 4)
May produce premature placental separation. - Parturition originating prior to 320 days gestation.
- Early umbilical cord rupture or excessive hemorrhage following severance.
Controversy exists regarding amount of blood which pulses from placenta prior to separation.
Neonatal Conditions
- Congenital abnormalities (see Chapters 41 & 42)
- Delayed Gut Closure due to delay in obtaining colostrum. Normally these intestinal cells for immunoglobulin absorption is rapidly used up and a normal GI barrier is formed. Bacterial absorption across the ‘open’ gut leads to septicemia.
If foal is weak begin antibiotics immediately and treat for 48-72 hrs. Or longer based on signs and CBC. Weak foals have enhanced gut bacterial translocation. - Failure of passive transfer.
This is usually caused by the foal being weak or by ingestion of poor quality colostrum (see Chapter 8).
Usually defined as less than 600-800 mg/dl of serum IgG at 16-24 hrs of age.
Infection occurs principally from GI passage of bacteria across the open gut, or by umbilicus and rarely the respiratory tract.
Risk of low IgG (<400 mg/dl) in a low risk foal with good exam and excellent management and no delay in nursing (rapid gut closure) is minimal based on some studies.
Neutrophils have decreased phagocytosis and chemotaxis before colostrum ingestion. - Meconium staining around eyes and muzzle may indicate aspiration pneumonia.
- Prematurity.
- Immature and small for gestational age.
- Adverse environmental conditions.
- Foaling in contaminated area.
- Cold and wet areas.
- Disrupted foaling due to over-observation.
- Infectious disease on the premises. - Death of dam.
Administer at least 1 liter of (good quality) colostrum as soon as possible by bottle if has an excellent suck reflex; otherwise use naso-gastric tube, 8 oz at a time, every 1 hr. - Foals which do not rise and nurse by 3 hours of age.
- Twins
Failure of passive transfer and septicemia are not uncommon in twins.
May be small for gestational age, weak, subject to hypothermia and other problems. - Rejection by dam
MARE VACCINATION vaccines certified for use in pregnant mares that represent disease conditions the foal will
be exposed to early in life. See AAEP for complete vaccination information.
Booster vaccination of mares 30 days before foaling –
- Botulinum toxoid, used where vaccine licensed.
- Tetanus immunization of the newborn - Two methods
Tetanus toxoid booster immunization of the mare in last 3-6 weeks before parturition preferred.
Tetanus antitoxin (1500 units) within 24 hours of birth.
Both methods provide 45 days of protection in the foal. - Rotavirus- (Rotavirus vaccine-)
Vaccinate mare at months 8, 9 and 10 months gestation
Use where rotavirus identified previously as a cause of foal diarrhea - Influenza – booster mares 4-6 weeks from foaling – NOTE- foals from influenza vaccinated mares do not respond to early vaccination. Begin foal vaccination from mares vaccinated at late term, at 6 months of age and use a 3 dose immunization series in the foal.
- Equine herpes virus 1 – Rhinopneumonitis - used to prevent mare abortion due to EHV-1 –use inactivated vaccine (Pneumobort K-Ft Dodge) at 5, 7 and 9 months of gestation.
- Equine herpes virus 4- vaccinate dam 4-6 weeks prior to foaling and start foal at 4-6 months of age using a 3 dose vaccination series.
- West Nile Virus- Mares need to be protected from this virus in endemic areas (all of USA). Vaccination is not a risk to pregnant mare or fetus. Pregnant mares respond poorly to vaccination.
- Cohen, N.: Causes of and farm management factors associated with disease and death in foals. J Am Vet Med Assoc 204:1644-51, 1994.
- Haas, SD, Bristol, F, Card, CE. Risk factors associated with the incidence of foal mortality in extensively managed mare herd. Can Vet J. 37:91-95, 1996.
- Koterba A.M.: Medical management of the equine neonate. CVMA Speakers Syllabus, 96th Scientific Seminar pp 282-367, 1986.
- Martens R.J.: Neonatal respiratory distress syndrome: A review with emphasis on the horse. Compend Cont Educ Pract Vet 4:S23-S33, 1982.
- Valla, W.E.: Management of the high risk pregnancy; the peripartum period. Proceed Amer Coll Vet Int Med 7th ACVIM Forum, pp 417-420, 1989.
- Neuhauser S, Palm F, Ambuehl F, Möstl E, Schwendenwein I, Aurich C. Effect of altrenogest-treatment of mares in late gestation on adrenocortical function, blood count and plasma electrolytes in their foals. Equine Vet J. 2009 Jul;41(6):572-7.
- Sonea I.: Respiratory distress syndrome in neonatal foals. Compend Cont Educ Pract Vet 7:S462-S469, 1985.
- Madigan, J.E.: What have colostrum deprivation models taught us about route of infection in the neonatal foal. Proceed of the Dorothy Havermeyer Workshop on Neonatal Foal Septicemia, 1995.
- Baldwin, J.L., Cooper, W.L., Vanderwall, D.K., et al: Prevalence (treatment days) and severity of illness in hypogammaglobulinemia and normogamma-globulinemic foals. J Am Vet Med Assoc 198:423-428, 1991.
Get access to all handy features included in the IVIS website
- Get unlimited access to books, proceedings and journals.
- Get access to a global catalogue of meetings, on-site and online courses, webinars and educational videos.
- Bookmark your favorite articles in My Library for future reading.
- Save future meetings and courses in My Calendar and My e-Learning.
- Ask authors questions and read what others have to say.
About
How to reference this publication (Harvard system)?
Author(s)
Copyright Statement
© All text and images in this publication are copyright protected and cannot be reproduced or copied in any way.Related Content
Readers also viewed these publications
No related publications found.
Buy this book
Buy this book
The eagerly awaited REVISED 4th edition is now available for download in ePDF format. For those who prefer the convenience of the traditional pocket-sized Manual, it's also accessible in that familiar form, perfect for slipping into your glove box or coverall pocket. Now, you can have it with you in whichever format suits your needs best.
For more details and to get your copy, visit https://www.equineneonatalmanual.com/.
Comments (0)
Ask the author
0 comments