Smithch20.manifestationsandmanagementofDiseaseinNeonatalRuminants Flashcards
Examples of bacterial/fungal infections in CATTLE that can cause placentitis and disease in newborn
Brucellosis Salmonellosis Leptospirosis Listeriosis Escherichia coli Corynebacterium spp Aspergillus spp
Examples of bacterial/fungal infections in SHEEP that can cause placentitis and disease in newborn
Chlamydia Campylobacter Coxiella Bluetongue virus Border disease
Examples of viral infections that cause disease in ruminant newborns
Bovine viral diarrhea virus (B) Blue tongue virus (B,O) Infectious bovine rhinotracheitis virus (B) Akabane virus (B) Parainlfuenza (B) Caprine herpes (C) Border disease virius (O) Equine herpesvirus (E) Equine viral arteritis (E)
B, Bovine; C, caprine; O, ovine
Differential diagnosis for weakness and depressed mentation after a period of apparently normal strength and mentation include:
Sepsis
Electrolyte and acid-base disturbances
Hypoglycemia
Hypothermia
What are common cause of calf mortality in the the united states
- Diarrhea
- Respiraotry disease
- Neonatal septicemia
What are common bacteria isolated from septic calves?
**Gram negative species
E. Coli Klebsiella spp Salmonella spp Campylobacter spp Staphylococcus spp Streptococcus spp. Other gram pos, other gram neg and aerobic bact
Sources of infection for septicemia in calves
Colonization of GIT with virulent bacteria
Infected umbilicus
Neonatal septicemia— primary goals of treatment are:
- Control infection
- Modulate the inflammatory response
- Support the animal during disease
Causes of birth asphyxia in ruminants
Placentitis Dystocia Caesarean section Premature placental separation Induced parturition Birth trauma Brachia plexus inuries Fractured rib, pneumothorax, hemothorax Ruptured bladder
Differential diagnosis for the weak/depressed large animal neonate congenital malformations:
Cardiac malfnormations
Central nervous system malformations (ie. Hydrocephalus, hdranecephaly)
Angular limb deformities
Arthrogryposis
Appropriate antimicrobial choices for septic neonates
3rd or 4th generation cephalosporins: 5- 10 mg/kg/day IM or IV higher than labeled dose 2.2 mg/kg
Sodium ampicillin: 10-20 mg/kg TID IV
Florfenicol: 20 mg/kg IV BID
What are common agents that cause meningitis?
E. Coli
Enterobacter spp
Salmonella spp
CSF analysis in menginitis
Pleocytosis
Xanthocrhomia
High protein concentration
Specific gravity: 1011 Total protein: 3.2 g/L Wbc: 40004-2400 cells/microL Percent lymphs: range 1-17% Percen tneuts: 73%, 78-100% Culture positive: 6/9, 11/19 cases
Normal CSF in calves
Specific gravity <1007 Total protein <0.4 g/L WBC <10 cells/microL Percent lymphs >80-90% Percent neuts: <10-15%
What is the ratio of CSF to plasma glucose concentration?
< 1
**d/t bacteria metabolism of glucose in CSF
Antibiotic penetration to the CSF is through which mechanisms
Passive diffusion down a concentration gradient
**lipid solubility— major determinants
Metabolic acidosis in neonatal ruminants is primarily associated with
INC concentration of D-lactate
—> d/t bacterial fermentation of carbohydrates in the GI tract of milk-fed calves
What are the consequences of hyponatremia:
Fluid shift from extracellular space to the intracellular compartment along the osmotic gradient—> swelling of cells
Clinical signs associated with hyponatremia
Neurologic disturbances
Depression
Disorientation
Convulsions
Value for hyponatremia in calves
<132 mmol/L
Severe: <120 mmol/L
What is the calculation to raise sodium to level to 125 mmol/L in first 6 hours
MEq sodium = (125- measured mEq serum sodium) x (0.6 x body weight in kg)
Hypernatremia in calves is usually caused by:
Ingesting milk repalcers high in sodium w/o access to fresh water
Or calves treated for diarrhea & receive oral electrolyte solutions
Pathophys of neurologic signs with hypernatremia
Brain adaptation to hyperosmolar state: shrinkage of neurons, = dehydration of neurons & brain shrinkage—>disruption of blood when brain moves away from calvaria
—> neuro signs worsen with treatment—> cerebrlal edema
Definition of hypernatremia
Sodium> 160 mEq/L or greater
**Serum sodium concentrations > 180. MEq/L indicate guarded to poor prognosis
What is the best sample to measure postmortem in calves to determine hypernatremia?
Ocular fluid
Clinical signs of hypernatremia
Early C/S: lethargy, depression
Advanced C/S: twitching of facial muscles, muscle rigidity, tremors, myoclconus
—> seizure and/or coma activity near death
What is the calculation for total body free water deficit for correcting hypernatremia:
0.6 x bodywt (kg) x [(current serum sodium concent./ normal serum sodium concen]-1)
**Administer fluids supplemented with sodium approximately equal to that of the calf
Differentials for weakness associated with micronutrient deficiencies that result from myodegeneration:
White muscle disease
Selenium
Vitamin E
Differentials for weakness with micronutrient deficiences results from demyleination:
Copper
Enzootic ataxia
Bacteria commonly isolated from vertebral body abscesses:
Trueperella pyogenes
—> suggesting chronic respiratory infection
Causes of paraplegia and tetraplegia
Spinal cord compression: vertebral body malformations, osteomyelitis or fractures
Ddx for paresis in goat kids
Caprine arthritis encephalitis virus (CAEV)
Enzootic ataxia
What are the 2 forms of enzootic ataxia (swayback)
- Neonatal — affected at birth
2. Delayed type— signs of incoordination at 14-30 days
What is the cause of enzootic ataxia (lambs/kids)
Low liver copper concentrations
Goat kids with neurologic form of CAEV have what C/S:
Mild to mod fevers
Cerebral signs: depression, head tilt, torticollis, circling
Causes of respiratory distress in neonatal ruminants: upper airway conditions:
Pharyngeal trauma Necrotic laryngitis Choanal atresia (nasopharyngeal atresia) Laryngeal edema Tracheal malformation: stenosis, collapse
Causes of respiratory distress in neonatal ruminants: lung parenchymal diseases
Pneumonia (bacterial or viral) Atelectasis Hyaline membrane disease Pulmonary edema, congestion Aspiration syndromes Air leaks (eg., pneumothorax) Pulmonary hemorrhage Transient tachypnea syndromes
Causes of respiratory distress in neonatal ruminants: non pulmonary causes
Congestive heart failure Central nervous system lesions Metabolic derangements (eg., acidosis, hypoglycemia) Severe anemia Hypovolemia Fractured ribs Nutritional myodegeneration of thoracic muscles or diaphgram Persistent pulmonary hypertension Birth asphyxia Pan, abdominal crisis Fever, high environmental tempreatures Excitement Pleural effusion (e.g., pleuritis) Endotoxemia and gram-negative sepsis
Cyanosis is not observable until when:
Partial pressure of oxygen reaches <35 to 40 mmHg
Abnormal head position in neonates ddx:
Respiratory difficulty (upper airway obstruction) Meningoencephalitis Otitis media Hypernatremia Polioencephalomalacia Congenital defects of the CNS Lasalocid toxicity
Cause of necrotic laryngitis
Fusobacterium necrophorum
Causes of pneumonia in calves less than 5 days of age
Neonatal septicemia (hematogenous in origin) Aspiration pneumonia (inhallation of fetal fluid, neconium, collostrum or milk, recumebncy, large holes in teat nipples, poor esophagela tubing) Pharyngeal dysfunction (whit emuscle disease)
Common pathogens of calf pneumonia
Mannheimia haemolytica Pasteurella multocida Mycoplasma bovis Mycoplasma dispar Salmonella dublin— fulminating pneumonia in 1-8 month old calves
Examples of respiratory viruses that predispose neonates to bacterial pneumonia
Bovine respiratory syncytial virus (BRSV)
Bovine coronavirus (BCV)
Bovine viral diarrhea virus (BVDV)
Risk factors for development of pneumonia in neonatal ruminants:
Failure of passive transfer
Poor nutrition
Additional environmental factors: extremes of temperature, poor ventilation, dust, ammonia, overcrowding
Antibiotics against mycoplasma spp
Tylosin Tetracyclines Erythromycin Tilmicosin Tulathromycin Gamithromycin Florfenicol Aminoglycosides Fluoroquinolones —> NOT susceptible to antibiotics that interfere with synthesis of folic acid or act on cell well
What are the 2 mechanisms of apnea:
- Central apnea— resulting from cessation of diaphragmatic activity
- Obstructive apnea— resulting from obstruction of airway (usu at pharyngeal level)
Causes of abdominal distention in calves:
—Obstruction: foreign body (hairballs in calves), malformation (atresisa coli, recti, ani), volvulus, torsion, strangulation
—Uroperitoneum: ruptured bladder (uncommon), torn or necrotic urachus, ureter
—Peritonitis: generalized infection, devitalized bowel, perforated gastric or intestinal ulcer, severe umbilical infection
—Gas and fluid accumulation in abomasum/intestinal tract: intolerance to diet, ileus, gastric ulceration, necrotizing enterocolitis, ruminal bloat
—Misc: hemoperitoneum, ruptured umbilical vessels, ruptures spleen or liver, congenital tumor
— ascites: severe liver or renal failure, severe hypoproteinemia
The closure reflex of esophageal groove in calves is maintained by what?
Suckling activity of the calf
Reasons for lack of esophageal groove closure:
Drinking out of buckets Variable milk tempreatures Stress Calves fed too low to the ground Milk flow rates are too high
What is the consequence of failure of esophageal groove closure:
Leads to rumen drinking— prolonged retention of milk in rumen results in anaerobic bacterial fermentation & production of lactic acid—> ruminal and systemic (METABOLIC) acidosis
Ruminal drinker syndrome can be prevented by:
Decreasing the volume of milk fed per feeding
Feeding from nipples rather than buckets
Introducing calf starter to promote ruminal development
What is a possible complication of severe bronchopneumonia in calves and why?
Bloat—> swollen mediastinal lymph nodes compressing the esophagus or compression or inflammation of the vagus
4 categories of ulcers described in calves
T1: nonperformating ulcer
T2: nonperforating ulcer with severe blood loss— see evere intraluminal hemorrahge
T3: perforating ulcer with local peritonitis
T4: perforating ulcers with diffuse peritonitis
Abomasal displacement is rare in calves but can be reported in calves with pneumonia (left sided displacment)
Pneumonia d/t altered vagal function is suggested (usu 6 to 14 wks of age)
What is the most common cause of abdominal distention of calves in the first week of life?
Intestinal atresia
Where is the most common site of intestinal atresia in calves?
Spiral loop of the ascending colon
Clinical signs of intussusception
Intermittent colic
Absence of feces
Melena
**signs are incosistant
Most common pathogens isolated from septic joints of neonatal calves are from:
Enteric organisms: -E. Coli Salmonella Streptococcus spp Staphylococcus spp T. Pyogenes (most freq from older calves)
Bacteria most commonly isolated from septic joints in lambs:
Streptococcus spp Colifroms Arcabobacterium pyogenes Erysipelothrix rhusiopathiae F. Necrophorum
Radiographic features of septic arthritis
Soft tissue swelling
Widening or collapse of the joitn space
Osteoporosis
Osteosclerosis
Clinical signs of femoral nerve paralysis
Inability to extend the stifle or advance the limb
Analgesia of the medial aspect of the limb down to the tarsus
**atrophy of the quadriceps is evident after 7-10 days if complete tear
The umbilical vein regresses into
The round ligament of the liver (w/in the falciform ligament)
Two umbilical arteries regress and become
The round ligaments of the bladder
Definition of omphalitis
Inflammation of umbilical structures that may include: umbilical arteries (omphaloarteritis), umbilical vein (omphalophlebitis), urachus, or tissues immediately surrounding the umbilicus
Anemia in ruminants secondary to iron deficiency are caused by:
Dec amount of iron in milk
Poor placental transfer of iron
Decrased itnestinal absorption
Differentials for diseases causing anemia
Frank blood loss d/t injury Iron deficiency anemia Neonatal isoerythrolysis Non-NI immune-mediated hemolytica anemia Blood coss caused by gastric ulcer Anemia secondary to bone marrow necrosis Anemia of chronic disease Hemolytic dz of newborn calves (anaplasmosis or babesiosis)
Differentials for fever in neonates
Bacterial or viral infections
Excitement
Seizures with subsequent generation of heat by muscular overactivity
Environmentally induced hyperthermia
Causes of cyanosis in calves due to cavdiovascular origin
Tetralogy of Fallot Triscupid atresia Truncus arteriosus Pentology of fallot Double outlet right ventricle Single ventricle Eisemenger compelx Ventricular septal defect Patent ductus arteriosus
Respiratory causes of cyanosis in calves:
Alveolar hypoventilation
Drug-induced central nervous system (CNS) depresson
CNS trauma or hemorrhage
Hypoglycemia or hypocalcemia
Altered neurologic function of spinal nerves (or resp muscles)
Thoracic cage abnormalities: pneumothorax, fractured ribs
Diaphragmatic hernia
Upper airway obstruction
Restrictive pleural space disorders: hemothorax, pleuritis
Hypoplastic lung
Impaired diffusion,, causes of cyanosis in calves
Pulmonary: pneumonia, edema, atelectasis Shunting Anatomic (congenital heart defects) Pathologic: pulmonary hypertension Ventilation- perfusion mismatch
Common signs of congenital heart defects in calves
Dyspnea
Cyanosis
Tachypnea
Failure to gain weight
Patent ductus arteriosus (PDA) describe the murmur
Continuous murmur localized over the left heart base
Differentials for icterus in neonatal ruminants
Sepsis (producing bacterial hepatitis) Anorexia Liver disease Hemolytic anemia Exposure to hepatotoxins
What is the cause of an enterotoxemic condition in nursing lambs, kids and calves characterized by icterus, hemoglobinuria, anemia and intravascular hemolysis
C. Perfringens type A
