Newborn Calf Scours

Franklyn Garry, DVM, MS

Neonatal Calf Losses

Death < 2 days oldTypically non-infectiousAssociated with physiological derangements

Birthing trauma, difficult postnatal adaptation, etc.

Death ≥ 3 days oldLikely infectious in nature

Potential physiologic problems that don’tkill may predispose to infectious problems

Calf Infectious Disease

Localized / superficial

Focal / inflammatory

Septicemic

Calf Scours

RotavirusCoronavirusCryptosporidiumE. coli - K99

Calf Scours Enteritis

Localized infection

Minimal inflammation

Minimal invasion

Disturbed GI function

Calf Diarrhea Agents from Neonatal Calves

0

10

20

30

40

50

60

Perc

ent o

f Sub

mis

sion

s

Crypto Rota Corona Sal A&E E. coli K99 E. coli

Reynolds. VMTRC. Personal Communication via J. Olson

Cryptosporidium parvum

Most common agent causing diarrhea,usually between 7 and 14 days of age

During average infectionCalves shed oocysts for six to nine daysCalves scour for average of three days50 million oocysts per gm fecesAverage calf sheds 40 billion oocysts

Primary infection route is fecal-oralInfective dose is between 10 and 100 oocyts

RotavirusOne of most common agents causing

diarrheaUsually seen 7 to 14 days of age Infectious dose is about 10 particlesWithin 48 hr post-infection, 1 billion viral

particles per gm of feces Infects and destroys cells of small intestine

CoronavirusTypically causes disease between 7 to 30

Days of AgeSimilar type of damage to intestinal villus as

Rotavirus, but more severeMore severe

More severe damage to intestinal villiAffects both small and large intestine

Normal Microvilli

Microvilli Blunted by rotavirus

Microvilli Destroyed by corona virus

Mechanisms of Diarrhea

Hypersecretion

Maldigestion

Malabsorption

100 lb calf

Diet (lb/d)

Milk ORS

10 0

10 2

10 5

10 7

10 10

10 12

Inflammatory Enteritis

Salmonellosis

Invasive E. coli

Clostridial enteritis

E. coli diarrhea Attaching and effacing E. coli: usually between 3 and 21

days

Focal Inflammatory DiseaseInflammatory response and damageDisrupt organ functionToxin production / systemic effects

SepticemiaDistribution through blood

Multiple organ involvement

Inflammation – widespread

Multiple mediating factors

SepticemiaSalmonella

18330%

Staphylococcus sp1

0%Streptococcus suis

41%

Bacterial539%

Mannheimia haemolytica

10%

Pasteurella multocida3

0%

E. coli36759%

Actinobacillus equuli ssp. Haemolytica

61%

Moeller Jr., 2005. VMTRC, Pfizer Calf Meeting

Most Scours in Calves are Mixed Infections

Most common combination of agentsare Cryptosporidium and RotavirusCrypto and rotavirus are the most

common mixed agents30% of calves with diarrhea that are

systemically ill are septicemicMost septicemic calves have had FPT

Learning issuesThe most common causes of calf diarrhea

are crypto, rota and corona virus = calfscours

These occur most commonly between 1 and2 weeks of age

These hurt or kill calves by causing fluid andelectrolyte loss

Antibiotics do not affect these bugs, and theinfection resolves on its own if the calfsurvives.

Learning issuesBacterial infections – Salmonella, E coli

and clostridium CAN cause diarrhea,but also invade other tissues

These occur over a broader time range- like 4 to 30 days

These kill calves by invading andcausing bad tissue inflammation and damage

Antibiotics may be useful against thesebugs

Diagnosis

History* Physical examinationLaboratory testingResponse to treatmentNecropsy

Physical Examination

Skin tentStrength and ActivityEyeglobe positionPeripheral perfusionDiarrhea

= evidence of dehydration

Physical Examination

TPRM M perfusionMentationSuckle responseAbdominal fillExtra-GI involvement

Diagnosis

Findings Suggestive of Septicemia

Physical findings

Red / inflamed mucous membranesProminent scleral blood vesselsDepression > dehydrationProfound depression w/o severe

diarrheaMultiple organ system problems

Physical diagnosis

Must compare groups ofobservationsDepression, diarrhea,

hydrationDiarrhea, extra-GI,

inflammationAge, clinical course, history

TreatmentScours

u Fluid Therapy - criticalOral, subcutaneous, intravenous

u Antibiotics - very limited efficacyMay be deleterious

u Adjunctive treatments - may have value

100 lb calf

Diet (lb/d)

Milk ORS

10 0

10 2

10 5

10 7

10 10

10 12

DiagnosisPhysiologic parametersFecal analysisELISA, EM, Parasitologic,

Bacteriologic CultureHemogramBlood cultureViral isolation

Diagnosis

Response to treatmentNecropsy

Other evaluations

Response to treatment IF you are treating calves with simple

scours, where the main problem isdiarrhea and dehydration

IF you treat scours calves early, whenthey have mild or moderate fluid loss

IF you use oral fluids and electrolytes withthe right amount and composition

THEN response to treatment will be verygood

Response to treatment IF you use oral fluids and electrolytes with the

right amount and composition And the calf response to treatment is POOR

OR-- IF calves have a more complex problem with

bacterial infection IF calves are very depressed or have fever and

signs of disease besides diarrhea

---THEN you need your veterinarian

NecropsyVERY underutilized in cattle medicineMost valuable diagnostic step if calves

are dying

Coordinate with your local diagnostic labProvide thorough information to the labSend the right samples for the right

reason

Newborn Calf Oral Fluid Therapy

Franklyn Garry, DVM, MS

Eye Globe Position

Smith GW. Vet Clin Food Anim 25 (2009)

Assessing Hydration Status

Smith GW. Vet Clin Food Anim 25 (2009)

Severity of diarrhea / dehydrationvs

Loss of base with Scours

NormalMildModerateSevere

0 - 5 mEq/L10 mEq/L15 mEq/L20 mEq/L

Goals of Scours Therapy

Maintain / improve hydrationCorrect acid - base imbalanceSupplement appropriate electrolytes

Judicious antimicrobialsHelp damaged gut / stop diarrhea ??

100 lb calf

Diet (lb/d)

Milk ORS

10 0

10 2

10 5

10 7

10 10

10 12

Treatment of Scours

Fluid Therapy !!!

Fluid Imbalances From ScoursHypotonic dehydrationMetabolic acidosis

HCO3 Na +Cl -K +

Oral fluid productsNeed to have sufficient sodium to make up

for lossesNeed to also have chloride and potassiumNeed to have alkalinizing abilityGlucose and glycine promote sodium

absorptionMust continue milk feeding – electrolyte

products do not have enough nutrition

Oral fluid products

Alkalinizing agentsBicarbonate (HCO3)AcetatePropionate

Alkalinizing agents

Bicarbonate increases blood pH butalso increases pH in abomasum

Increasing abomasum pH may allowbacteria to move to lower bowel

Acetate and propionate increaseblood pH but do not affectabomasum

Oral fluid products

ResorbSodium too lowNo alkalinizing agentPoor choice for scours

Additional products without alkalinizing agent

Bovine blueliteBlue RibbonRenewCalf RestartSav-A-CalfOne Day Response

Additional poor choicesAdvance ArrestLow sodium, low alkalinizing

DeliverLow sodium, poor alkalinizing

Oral fluid products Good choices

HydrafeedEntrolyte and Entrolyte HERevitilyte

All have high levels of Bicarb

Oral fluid products Very good choices

Land O Lakes Base plus AddPack

DiaqueHydraLyteEpic Calf Electrolyte

All have acetate instead of bicarb

Infectious disease preventionMinimize exposure - maximize resistanceColostrumNutrition

Cold weatherPhysiological ‘strength’

Warm / dry/ protectedThermoneutral zone

Fresh waterLow stress