Parturition and Foal Neonatal Care LACP pg 163

Parturition and Foal Neonatal Care LACP pg. 163

Gestation Length n Average 335 -340 days. Variable- breed, sex of foal, plane of nutrition, etc

Equine Gestation Hormones Progesterone/Progestogens n n n Progesterone initially rises, followed by a slight ↓ then ↑ to a peak at d 80, then gradually ↓ to 1 -2 ng/ml during mid-late gestation (d 150). Second ↑ associated with formation of accessory & secondary CL. Late gestation progesterone rises (last month of pregnancy)

n n Once embryo enters uterus, it migrates throughout the uterine body and both horns until 16 -17 d (becomes to big to pass through horn. This migrations signals the dam that she is pregnant. (contacts endometrial surface repeatedly) FIXATION Embryo Up to 40 d Fetus after 40 d

60 d-7 months- fetus develops slowly (fetal organ development phase) n 8 months-parturition increase in size to about 60% of its weight in the last 3 months. n

Placenta n n Placenta takes over progesterone production ~d 100 until foaling. Complete placental formation is done at 150 days. DAY 150 - Firm placental attachment

n n Chorioallantois- outer fetal membrane, chorionic side attaches to dam- red and velvety, allantoic side- fetal side bluish grey in color. Amnion is thin, white membrane covers the fetus

Impending Birth Vaccinate & Deworm 30 day prior Most Obvious n Hypertrophy mammary glands obvious from 8 th month q n n n Maiden may display little until just before foaling Distention of the teats 4 -6 d pre-foaling Waxing of the teats 1 -72 hrs pre-foaling An increase in milk Ca 1 -3 d pre-foaling

Fescue Toxicity n Pull mare off fescue at least 1 month before foaling.

Impending Birth More Subtle Signs n Softening and flattening of the muscles in the croup n Vulva becomes relaxed & elongated. n Visible changes in the position of the foal n Vulva – thick & puffy with edema and may elongate

Stages of Parturition n Stage 1 q q q Onset: initial uterine contractions End: rupture of chorioallantois (water bag “water breaks”) 2 -4 hr Mare may stand up, pacing, lie down, roll, pace, look or bite at flanks, sweat, frequent urination Foal is being pushed toward the cervix

Stages of Parturition n Stage 2 q q q Onset: rupture of chorioallantois (8 -20 L) End: delivery of fetus- cord is broken Timeline 20 -30 min Contractions occur in groups of 3 -4 followed by a rest period of 3 to 5 minutes Forefeet visable, soles pointing down Oxytocin release, uterine contractions reinforced

Ensure a clear airway by clearing membranes and fluids from the nostrils n n When the chest is through the vulva the foal can breathe on its own. May go in & remove the amniotic sac. Not breathing – rub foal, take straw and put in nose, breath into nose

Foaling Emergencies May Need Assistance n n n Red mass evident at vulva (placenta seperation) Strong straining & no feet evident at vulva within 5 min Heavy straining with feet in vulva but no further progress in 10 min One foot missing No progress for more than 15 min after first water breaks Mare foals while standing “Red Bag”

Foaling Emergencies May Need Assistanc n If the chorioallantois does not break and the velvety-red surface of the chorioallantois is presented at the vulva, it should be immediately ruptured because this indicates that the placenta is separating from the endometrium and that fetal oxygenation will be impaired n - cut placenta and pull foal (fescue toxicity)

Stages of Parturition n Stage 3 q q End: passage of the fetal membranes Expel placenta 30 minuets -4 hrs post-foaling If no passed within 4 -6 hours, the placenta is considered to be retained– metritis, necrotic uterine wall, septicemia, laminitis Can tie placenta in knot above hocks • Examine Placenta

n http: //video. google. com/videosearch? q=horse +breeding&hl=en&emb=0&aq=f#q=foaling&hl =en&emb=0

Placenta Examination • Arrange the membranes in a capital "F" position, with the pregnant horn uppermost and the body forming the vertical bar of the "F" • Tip of the nonpregnant horn is the most likely part of the placenta to be retained • Placenta Examination • Weight • Length of umbilical cord & location • Appearance of gross lesions, missing pieces

Retained Placenta: Treatment n n n n After 2 hrs Oxytocin Infusion of fluid into allantoic cavity Antibiotics Non-sterioidal anti-inflammatory drugs Frog support pads Deeply bedded stall Pictures

Abortions n n No common, greater in mares over 14 yrs Twins- 90% abort, Abortion in mid to later gestation may occur in single horse, or many “abortion storm” (viral or bacterial) If this happens fetus should be placed on ice and examined by vet within 12 hours.

Abortion time Control EHV 6+ mo Vaccine EV arteritis 6+ mo Vaccine Lepto 5+ mo Isolation Mare Repro. Loss Syndrome 45 -120 d 10+ mo Eastern Tent caterpillars Placentitis 5 -9 mo Caslick Umbilical torsion Anytime None Twins 5+ mo None Stress Anytime Decrease stress Endotoxemia Anytime Determine cause and avoid

Postpartum Mare & Foal Care Umbilical Cord Care n Allow foal to break fetal membranes. n Never cut the cord. n Spray or dip umbilical cord stump with antiseptic solution 3 -4 X per day for 3 -4 days Ascending placentitis Premature seperation

Umbilical cord is made of Umbilical vein, 2 umbilical arteries, and urachus n Vein becomes the falciform ligament Arteries become the round ligaments of the bladder n Best to let the cord rupture naturally

Patent Urachus n n The urachus is usually patent at birth and close naturally within 48 hr. as the umbilical stump withers and dries If urine passes through the umbilicus after 48 hr. of age, this is referred to as persistent patent urachus.

Neonatal Care n n n The neonatal period is the period following birth, which most clinicians consider the first 4 to 5 days This period is one of susceptibility to many diseases and conditions that can be threatening to the immediate and long-term health of the foal Good neonatal care is a combination of sound management practices and recognition of normal and abnormal conditions

Foal Facts n n Newborn foal should exhibit a suckle reflex at 20 minutes after birth, stand within 30 -60 min. and nurse within 60 to 180 min. The first urination occurs within 10 hours and the meconium should be passed by 24 hours after parturition. (Meconium is the first fecal material that the newborn foal normally evacuates. It appears in pelleted form, brown to black in coloration. They must pass this or become impacted. ) LACP pg. 165

Colostrum First milk secreted by a mare coming into lactation (poor lactation can be supplemented with domperidone) Production n During last 2 -4 weeks of gestation n Under hormonal influences Importance n Transfer of passive immunity to the suckling foal (“Liquid Gold”) Specificity of protection achieved by vaccinating pregnant mares 30 -60 days before parturition n n Produced only once – beware of leakage! n Provides energy to foal n Encourages passage of meconium

Colostrum Quality n Relates directly to antibody content n Good quality: ü ≥ 50 (70) g/L Ig. G and specific gravity > 1. 060 ü Thick, sticky, yellow secretion q All foals should have Ig. G measured between 8 -24 hours

Colostrum Evaluating Colostrum Quality When? n Assess before foal suckles How? n Physical appearance ü Thick, sticky, yellow secretion indicates good quality ü Dilute, white or translucent secretion indicates poor quality ü Stall Side Tests Banking of Colostrum n Only good quality colostrum n Storage at - 20ºC: q q n Ig. G concentration stable for 12 months Other immune components (complement, etc) and nutritional components decrease significantly Storage at -70ºC: q Permanent maintenance of all components

Colostrum Evaluating Colostrum Quality ARS Refractometer n Designed for measurement of sugar concentration of solutions (BRIX type) n 1 -2 drops of colostrum needed n Results in less than 1 minute http: //www. arssales. com/equine/html/refractometer. html

Colostrum Evaluating Colostrum Quality ARS Refractometer - Results

Foal Immune Status Evaluation of serum Ig. G status When? § Typically at 12 -24 h after birth § § Peak serum levels of Ig. G achieved by 18 h Absorption of immunoglobulins from small intestine essentially complete If failure of passive transfer: treat with IV plasma Can measure early at 6 -12 h § § Ig. G first detected in foal’s serum at 6 h of age If no Ig. G or very low level at 6 -12 h: can give colostrum to increase levels

Foal Immune Status Evaluation of serum Ig. G status Snap Foal Ig. G Test n n n ELISA Use whole blood, serum, or plasma Calibrator spots indicate Ig. G levels of 400 and 800 mg/dl Sample color is proportional to Ig. G content Results in 10 -15 min. Expensive but convenient

Foal Aftercare: within 1 st 24 hours n n n Give enema to prevent Meconium impaction Give Tetanus antitoxin Check for presence of suckle reflex Check for any malformations or deformities Take blood sample from foal. Perform a physical

Neglected foals

n Milk can be expressed from the mammary gland by use of an inverted 60 -ml dosing syringe to apply suction

Common Foal Diseases n n n Sepsis Perinatal Asphyxia Prematurity Neonatal Diarrhea Respiratory Disease

Sepsis n n Common in foals Fever, elevated heart rate, or respiratory rate n Causes: improper umbilical care, failure of passive transfer, poor sanitation, maternal illness such as placentitis n Treatment: intensive nursing care, immunoglobulin therapy, antimicrobial treatment

Perinatal Asphyxia n n Lack of oxygen “dummy foal syndrome” cerebral edema and ischemia and necrosis of the brain n 48 hours after birth foal my lose the affinity for the mare, become unable to suckle, wander aimlessly, and potential for seizures. n Prognosis is good if there are no seizures

Prematurity n Equal to or less then 320 days n Low birth wt, weakness, short hair coat, increased joint motion, rear limb flexural laxity, take longer to stand, suckle reflex may lack vigor, domed forehead, floppy ears n Survival depends on degree of complication

Diarrhea n n Common Frequency of diarrhea, suckling of foal, weather other foals are affected n Cause: Foal heat diarrhea, rotavirus, coronavirus, septicemia, salmonella, clostridium, Strongyloides westeri, lactose intolerance. n Iv fluid therapy, probiotics, analgesics, plasma

Respiratory Disease n n n Can be hard to diagnose: restlessness and agitation, increased respiratory rate or distress. Diagnosis- thoracic radiograph, arterial blood gas, pulse ox, ultrasound Cough is rarely seen, nasal discharge uncommon, respiratory rate and rhythm can be unreliable, mucous membrane won’t reflect mild to moderate pulmonary disease, Thoracic auscultation can be misleading

n n n n n Bacterial pneumonia Viral pneumonia Fungal pneumonia Milk aspiration Acute respiratory distress syndrome Persistent pulmonary hypertension Fractured rib Pneumothorax Pleural effusion

n Examination of the inner ear reveals petechiation

n The critically ill neonatal foal should be placed on a warm, well-padded surface in semisternal recumbency

n The jugular groove is widely clipped and prepared with sterile solutions before intravenous catheter placement

n Proper restraint of the foal is achieved by gently cradling one hand under the neck and grasping the base of the tail with the other hand.

Limb Deformities n n n Angular- Varus, Valgus, Windswept Axial- off set knees Rotational- muscular Spiral- toed in Flexor – week or contracted flexors Most are congenital, premature, dietary, blunt trauma to the growth plate, uneven hoof balance

Angular n Valgus n Varus n Windswept

Treatment n n n Stall rest X-rays Medial extensions Self correction (valgus) Surgical correction Therapeutic trimming

Axial- off set knees n No treatment, undesirable in race horses, can lead to unsoundness

Rotational- toed out n n Self correction Muscular development of thoracic muscles

Spiral – toed in Fetlock is in normal alignment n No treatment, corrective shoeing masks problem n

Flexor- contracted n Bone is longer then the surrounding tendons

treatment n n n Tetraclycine- shown to relax the muscle/tendon unit Bandaging Passive extension stretching Air splints PVC splints surgery

Flexor- laxity n rest

n n n Bone growth catches up with tendons Swimming Care for soft tissues if damaged