Neonatology Flashcards
beef calf mortality
Birth to Weaning – 6-8% average
57% in first 24 hours
75% in first 7 days
causes of beef calf mortality
Dystocia – 17.5% Stillbirth – 12.5 % Hypothermia – 12.2% Diarrhea – 11.5% Respiratory – 7.6%
factors affecting the neonate
- Proper fetal development
- Successful parturition
- Adaptation to Extrauterine life
- Nutritional support
- Colostrum and passive transfer
- Infectious disease
oranogenesis
12-42 days
organ development
50-150 days
organ growth and maturation
last trimester
70% of birth weight
fetal membranes and fluids
- Transfer oxygen and nutrients
- Elimination of fetal wastes
- Fetal protection
parturition
Severe stress w/ some oxygen deprivation
Adaptive mechanisms
Catecholamine surge
High serum cortisol
Point : Effects of catechalamines and cortisol can
mask conditions in neonate immediately
postpartum
Crashes – can and do occur a few hours later
extrauterine adaptation
Most fetal organs well developed by late gestation
Duration of transition varies for each organ system
Respiratory – immediate
Immune – weeks to months
Each neonate adapts at own rate depending on
vigor, strength, stress of parturition, maternal
support, environment
Fetal-> Neonatal blood circulation
Initiate pulmonary function
Regulate acid-base balance
Engage metabolic pathways for energy metabolism
Thermoregulation
Absorb maternal immunoglobulins
passive transfer of immunity
fetal circulation
Placenta Umbilical vein Ductus venosus Ductus arteriosus Foramen ovale Pulmonary circulation High pressure, low flow system 10% cardiac output Umbilical arteries
cardiopulmonary changes at birth
Umbilical separation Aeration of lungs Low pressure, high flow Surfactant Laryngeal sphincter Closure of: Ductus venosus Ductus arteriosus Foramen ovale Pulmonary fluids Heart rate: 100-140/min (120) Respiratory Rate: 30-60/min(48)
initiation of spontaneous respiration
Loss if immersion reflex which inhibited breathing
in-utero
Respiratory centers of the medulla are stimulated
by cold, light, tactile sensations and flexion of limbs
Arterial pO2 and PH decrease, pCO2 rises and the
peripheral and central chemoreceptors are
maximally stimulated
pulmonary events associated with birth
Thoracic cavity compression in normal anterior
presentation
Partial expulsion of fluids from lungs
Elastic recoil of thoracic cavity after passage
through vagina causes aspiration of air into lungs
and upper airways
Diaphragmatic rhythmic contractions causing a
increasing negative intrathoracic pressure aiding in
further inflation of lungs
Absorption of lung fluids
causes of respiratory distress and acidosis
Partial or premature placental separation Prolonged uterine contractions Umbilical cord compression Maternal hyperventilation Cesarean section/malpresentation Pharmacologic agents Immaturity
stimulating respiration
Clear fetal membranes Clear airway fluids Suction vs. gravity Stimulate breathing Massage Nasal stimulation Artificial respiration
acid-base balance and energy metabolism
Transient mild metabolic acidosis and respiratory
acidosis following rupture of the umbilical cord.
Acid-base balance is usually normal prior to separation
After separation the acid-base changes are due to
anaerobic metabolism and establishing respiratory
function
Metabolic acidosis usually corrected by 1-4 hours post
birth
Respiratory acidosis often persists for 48 hours or longer
energy metabolism
Energy sources: Hepatic and other glycogen stores Utilized within 4-6 hours Brown adipose tissue Utilized within 1-5 days Nutrition of dam Colostrum and milk Required for survival
thermoregulation
Environment Moisture Wind Temperature Maternal Behavior Energy Activity
hypothermia
Body Temp <98 F Suckle reflex Shivering? Energy – warm colostrum/milk Warm Calf/lamb Hot water bath vs. warm air Dry Warm oral fluids Calf/lamb coats Heat lamps Do not warm before administering an energy source (i.p. dextrose or warm colostrum.) Causes seizures
findings in neonates born in severe dystocia
Meconium staining
Severe metabolic acidosis/respiratory acidosis
Elevated circulating lactate levels
Organ system dysfunction/Neonatal asphyxia
Difficulty maintaining body temperature
Erratic blood glucose maintenance
Central nervous system damage
Neonates surviving these events may show an
increased risk of disease later in life.
successful parturition
Health of Dam Size of fetus Presentation and posture Anterior presentation Posterior presentation Assistance
stage one of parturition
Myometrial contractions
Positioning of fetus
Restlessness of mare
stage two of parturition
Rupture of chorioallantois
Delivery of fetus within 20 min.
stage 3 of parturition
- Myometrial contractions continue
* Explusion of placenta
PE of neonatal foal
Length of gestation 315-365 days Time to stand 1 hour Time to suckle 2 hours Passage of the placenta 3 hours
post partum care- foals
Umbilicus
Allow to break naturally – 5 cm from body wall
Manually break if necessary
Never cut
Dip umbilicus- 0.5% chlorhexidine solution
Suckling behavior
Clean bedding
Wash udder and perineal area
20 ml/kg (2-4 liters)of good quality colostrum (sp.
Grav.>1.060)
FPT
Premature lactation – twin pregnancies, placentitis, premature placental separation Failure to ingest colostrum Low IgG content of colostrum or failure to produce colostrum – Fescue toxicosis Poor absorption of IgG – Ill and premature foals
neonatal maladjustment syndrome
- Gross behavioral abnormalities
- Multiple organ system dysfunction
- Hypoxic-ischemic damage to the CNS
- Dummy foal, barker, wanderer
Clinical presentation Clinically normal from birth – 36 hrs Sudden loss of suckle reflex Weakness, disorientation, aimless wandering Simi-comatose or seizing Clinical course/Prognosis Improvement by 48-72 hrs Signs persisting for > 4 days – guarded prognosis
patent urachus
Hospitalized debilitated neonates Simultaneous infection of the umbilicus (Navel Ill) Foals straining to defecate Treatment: Cauterize Surgical excision
neonatal isoerythrolysis (NI)
Mare produces antibodies against foal’s RBC’s
Antibodies ingested via colostrum
Etiology
Foal inherits blood group antigens from sire
History of blood transfusion
Aa/Qa negative mares most commonly affected
Antibodies not made during first pregnancy
NI clinical signs/diagnosis
Foals born healthy Signs develop at 24-36 hrs Lethargy, weakness, pale membranes Severe jaundice (icterus) Diagnosis: Cross match Hemoglobinemia and hemoglobinuria ( intravascular hemolysis) Coomb’s test
NI treatment
Minimize stress, restrict exercise Intravenous fluids, diuresis Broad spectrum antibiotics Whole blood transfusion for severe anemia (PCV 10-15%) Restrict nursing
NI prognosis
- Depends on quantity of antibody ingested
- Rapidity of onset of signs
- Degree of anemia
- Prevention
- Screening for anti-RBC antibodies
ruptured bladder (uroperitoneum)
History Commonly occurs during parturition +/- history of dystocia Male foals>female foals Typically normal at birth +/- straining to urinate
surgical treatment
Post-operative care Broad spectrum antibiotics Urinary catheter Prognosis Good Complicated by concurrent septic
foal diarrhea
Causes
Bacteria – Clostridium sp. Salmonella, R equi
Foal heat
Viruses – Rotavirus
Paraites – Strongyloides westeri, S. vulgaris,
Cryptosporidium
Nutritional – lactase deficiency
foal diarrhea therapy
Fluid therapy – sodium containing fluids Dextrose/potassium supplementation Systemic antibiotics Parenteral nutrition Intestinal protectants – peptobismol Anti-ulcer medications – preventative Plasma/hetastarch – protein loss Desitin ointment
colic
- Meconium impaction
- Atresia (anus, colon)
- SI intussusception
- SI volvulus
- Ascarid impaction
colic treatment
Warm soapy water enema Acetylecysteine retention enema Analgesics – banamine, ketoprofen Mineral oil Fluid therapy trocarization
gastroduodenal ulcers
Gastric ulcers Bruxism, decreased appetite Occur in squamous non-glandular portion of the stomach Pyloric/duodenal ulcers Impaired gastric emptying Excess salivation, bruxism, dorsal recombancy.
causes for ulcers
Multifactorial – stress, concurrent disease,
nonsteroidal anti-inflammatory therapy
diagnosis of ulcers
Clinical signs
Endoscopy
Abdominal radiography with contrast
ulcer treatment
Decrease acid secretion – Ranitidine,
cimetidene, omeprazole
Gastric protectants – Sucralfate
Promote gastric emptying - Metaclopramide
botulism (shaker foal synfrome)
Clostridium botulinum
Clinical signs
Progressive muscular weakness
Toxin blocks acteylcholine release at the
presynaptic junction – neuromuscular weakness
Route of infection
Ingestion of organism which elaborates toxin
clinical presentation of botulism
>4 weeks of age Progressive weakness to recombancy Bright and alert Milk dribbling from mouth/nostrils Poor tongue, tail, and anal tone Dilated pupils Death due to respiratory paralysis
treatment of botulism
Antitoxin (specific for type involved) Penicillin IV Avoid IM penicillin, tetracycline's, aminoglycosides Indwelling nasogastric tube Ventilator support
prevention of botulism
vaccination with type B toxoid
Environmental?
fetal immune system
Development 50 to 180 days of gestation Self recognition Maturation Functional at birth Naïve Less responsive
passive immunity
Colostrum Last 4-6 weeks of gestation Maternal Antibodies (IgG) Energy rich Requirements Adequate Production Adequate Intake Adequate Absorption
antibody/immunoglobulin five classes
IgG IgM IgA IgE IgD
IgG
most abundant, most prevalent in serum and
colostrum
IgM
most efficient in neutralization of viruses and
toxins.
IgA
secreted on mucosal surfaces of respiratory,
intestinal and genital tracts and is the primary
humoral defense in these tracts of the new born
IgE
allergic reactions
IgD
mice and humans
adequate colostrum production
- Beef vs. Dairy
- Heifers vs. Cows
- Vaccination
- Nutrition
- Full Gestation Length
- Storage
FPT
failure of passive transfer
adequate colostrum intake
- Beef colostrum: 1-2 quarts
- Dairy colostrum: 4 quarts
- Maternal behavior
- Calf strength
- Dummy calves
- Nursing vs. tubing
adequate colostrum absorption
Open gut First 6 to 12 hours Decreased absorption Hypoxia Compromised circulation Hypothermia Competing proteins Too late
monitoring passive immunity
Colostrum Quality Calf Serum IgG Total Protein (>5.5 mg/ml) Precipitation tests Association with Disease Ig G status Exposure
total protein disease risk
- TP>5.5 mg/ml = adequate
- TP<5.0 mg/ml = Failure
- Mortality Risk:
- TP 6.0-6.5 = MR of 1
- TP 5.5-6.0 = MR of 1.4
- TP 5.0-5.5 = MR of 2.1
- TP 4.5-5.0 = MR of3.3
- TP < 4.5 = MR of 6.0
colostrum supplements
- Calf needs at least 100 grams IgG
- Colostral Supplements < 10 grams
- Compete with maternal IgG
- Inadequate
- Plasma
colostrum storage
Frozen Colostrum 6-12 months Beef vs. Dairy Concentration Contamination Thawing Warm water – 110 F Microwave – 60% power, in a time pinch, and known good quality colostrum. Microwaves will destroy immunoglobulins.
neonatal infectious disease
- Neonatal Septicemia
- Calf Scours
- Pneumonia
physiological parameters
- Temperature: 100-103 F
- Heart rate : 100-140/min (120)
- Respiratory rate : 30-60/min (48)
neonatal septicemia
Bacterial infection in the blood
entry of septicemia
Respiratory tract
Intestinal tract
umbilicus
prevention of septicemia
Colostrum
Vigorous Calves
Environment
Dip naval
symptoms of septicemia
Clinical signs Weakness Decreased nursing Scleral injection Mucous membranes Increase HR and RR +/- Diarrhea Fever is rare (subnormal temp)
treatment of septicemia
- Antibiotics
- Anti-inflammatory drugs
- Fluids
- Plasma or blood transfusion
- Nursing care
calf/lamb scours
Bacterial E coli salmonella Viral Coronavirus Rotavirus Protozoal Cryptosporidium Coccidia
factors in scours
- Environmental exposure
- Inadequate colostrum
- Dystocia
- Poor nutrition of the dam
- Health of dam
- Mothering ability
pathogenesis
Secretory diarrhea E. coli Malabsorptive diarrhea Coronavirus and Rotavirus Cryptosporidia Osmotic diarrhea Excessive milk Maldigestion
e coli
Enterotoxigenic Secretory Other types Invasive Hemorrhagic Pathogenic Stable in environment Susceptible to disinfectants
rotavirus and coronavirus
Infect intestinal epithelium Destroy epithelial cells Digestive function Secretory function Absorptive function Moderately stable in environment Susceptible to disinfectants
salmonella
- Colonize intestine
- Destroy intestinal epithelium
- Invade into tissues
- Septicemia
- Stable in environment
- Susceptible to disinfectants
cryptosporidium
Invade into intestinal epithelium Shed in high numbers Immediately infective Stable in environment Resistant to disinfectants Reservoir and sources Rodents and wildlife Infected calves to 4-6 months Not adult cows
calf scours- signs
Diarrhea – white, yellow, red(blood) Dehydration Weakness Decreased nursing Increased HR and RR Scleral injection Mucous membranes
scours treatment
Maintain hydration status Oral fluids Sub Q fluids IV fluids How much fluids % dehydration x body weight (kg) Kilograms -> liters or quarts
determining hydration status
1.Take the % dehydrated and multiply by the calf’s body
weight in kg.
2.For example, an 80 lb. (36 kg) calf is determined to be 9%
dehydrated.
.09 X 36 kg = 3.24 – This means that 3.24 liters of fluid (oral
electrolytes, SQ, or IV fluid) are required to replace what has
been lost.
3.After the initial calculated fluid dose is administered,
additional fluids can be given at a rate of 5 mL for every 2.2 lbs., every hour. In addition to the 5 mL/2.2 lbs/hour, an additional 1-4 liters each day may be required to keep up with continued fluid losses because of diarrhea, etc.
1 gallon = 3.7 liters and 1 kg =2.2lbs
oral fluid treatment
Can calf suckle? Is calf <5% dehydrated? Fluid choice Commercial vs. home made Alkalinizing vs. Non-alkalinizing How much? How often? How long? Two feedings -> feeding q 2 hours Continue milk feeding? 30 min. apart. Do not mix fluids with milk replacer.
subcutaneous (SQ) fluid administration
Calves 6-8% dehydrated Warm fluids to body temp Sterile isotonic fluid (0.9% saline) No glucose in fluid Administer skin areas of neck, shoulder, and behind elbow. 500ml in one location, 2 liters total 4-6 hours to absorb
intravenous (IV) fluid administration
When dehydration > 8% Sterile catheter Bicarbonate/glucose may be needed Two thirds of calculated amount given in first hour. Give rest over 2-3 hour period Additional 5 ml per 2.2lbs per hour Additional 1-4 liters/day may be needed due to fluid losses from diarrhea, etc.
scours treamtent
Antibiotics Some calves are also septic Look for signs of sepsis Choice of antibiotic Duration of treatment Anti-inflammatory drug? Severity Ulcers
vaccinations
When? What? E. coli Rotavirus and Coronavirus Clostridium perfringens types C and D 4-way respiratory MLV vs. killed vaccines Calf vaccines
managing calf scours
Calve heifers in a separate location Quarantine all calves with diarrhea and their dams Nutrition of dams in late gestation Protein copper Manage the environment
