64
NEWBORN CALF VITALITY: RISK FACTORS, CHARACTERISTICS, ASSESSMENT, RESULTING OUTCOMES AND STRATEGIES FOR IMPROVEMENT Christine Murray, PhD Candidate

NEWBORN CALF VITALITY: RISK FACTORS, … · newborn calf vitality: risk factors, characteristics, assessment, resulting outcomes and strategies for improvement christine murray, phd

Embed Size (px)

Citation preview

NEWBORN CALF VITALITY: RISK FACTORS, CHARACTERISTICS, ASSESSMENT, RESULTING OUTCOMES AND STRATEGIES FOR IMPROVEMENT

Christine Murray, PhD Candidate

Outline

Dystocia: effects on the calf Causes of reduced newborn vitality Consequences of reduced vitality Vitality scoring Methods to improve calf vitality Study results Biomarker for calf vitality

and long-term health Conclusions

Dystocia: Effects on the Calf

Parturition can be the most hazardous and traumatic event in the life of a calf

Dystocia and subsequent health events account for up to 50% of all calf deaths

In severe dystocia cases, calves have:

20.7 greater odds of stillbirth

1.7 & 1.3 greater odds of being treated for respiratory & digestive disease, respectively

6.7 greater odds of mortality

(Lombard et al., 2007; Furman-Fratczak et al., 2011)

Dystocia: Effects on the Calf

Factors causing dystocia may include: Pelvic dimension of the dam

Calf size

Feto-pelvic disproportion

Calf presentation

Inappropriate timing of intervention or excessive force applied during delivery

Maternal factors, such as weak labor, insufficient dilation of the cervix and uterine torsion

(Meijering, 1984; Schuijt, 1990; Mee, 2008)

Dystocia may have implications for calf vitality, as well as long-term health and productivity

Vitality: having the capacity to live and grow with physical and mental energy and strength

Physiological effects of dystocia:

Inflammation, pain, injury, inability to maintain homeostasis, hypoxia and acidosis

Behavioral repercussions:

Reduced motivation to perform natural behaviours for survival, including standing up and suckling colostrum after birth

Dystocia: Effects on the Calf

(Breazile et al., 1988; Besser et al., 1990; Carstens, 1994; Barrier et al., 2012)

Outline

Dystocia: effects on the calf

Causes of reduced newborn vitality

Pain, injury & inflammation

Hypoxia/acidosis

Respiratory acidosis

Metabolic acidosis

Impaired thermoregulation

Causes of Reduced Calf Vitality

(Meyer et al., 2000; Lombard et al.,2007; Waldner and Rosengren, 2009)

Improper obstetrical assistance & excessive force: Fetal Blood loss

Improper clamp timing

Premature umbilical cord rupture

Fractures Long bones

40% rib fractures

10% fractured vertebra

Trauma Liver rupture

Tracheal collapse

Meningeal hemorrhages

Pain, Injury and Inflammation

Hypoxia/Acidosis

Hypoxia refers to an inadequate supply of oxygen to the cells & tissues of the body

Premature umbilical cord rupture causing an inability to breath = Respiratory Acidosis

Termination of blood oxygenation from the placenta

Intense and prolonged labor contractions

Trauma during forced extraction

If severe, fetal tissues will derive O2 from anaerobic glycolysis = Metabolic Acidosis

Asphyxia can cause decreased blood flow to the liver and kidneys leading to hepatic necrosis, liver dysfunction and renal tubular necrosis

Other implications include aspiration pneumonia, edema, bleeding, and death

Schuijt and Taverne (1994) found that calves born from a severe dystocia had more serious acidosis, took longer at achieve a normal pH (>7.2) and had a greater risk of mortality

(Mulling, 1977; Ikeda et al., 2000; Poulsen and McGuirk, 2009)

Hypoxia/Acidosis

Hypoxia/Acidosis

7.05

7.1

7.15

7.2

7.25

7.3

7.35

15 30 45 60 75 90 105 120 135

pH

at

SR

Duration of Calving (Min)

0 people

1 person

2 people

3 people

(Murray et al., unpublished results)

Depending on the degree of stress, calving environment and season of birth, maintaining homeostasis can be challenging

Decreased available energy needed for the mobilization and metabolic activity of brown adipose tissue during non-shivering thermogenesis

Reduced muscle tonicity, preventing shivering

Less able to withstand cold stress

Thermoregulation

(Stott and Reinhard, 1978; Okamoto et al., 1986; Vermorel et al., 1989; Bellows and Lammoglia, 2000)

Newborn calves can generate body heat through physical activity

Standing up, walking and consuming colostrum may be challenging for calves with low vigor, especially in temperatures outside of their thermoneutral zone (10-25°C or 50-78°F)

Energy and heat acquired through colostrum ingestion may also be delayed or reduced in calves with low vitality

Thermoregulation

(Vermorel et al., 1989; Grove-White, 2000; Barrier et al., 2012)

Outline

Dystocia: effects on the calf

Causes of reduced newborn vitality

Consequences of reduced vitality

Dystocia causing pain, injury, inflammation, hypoxia, acidosis, and impaired thermoregulation all lead to calf weakness and reduced vitality

Decreased ability to perform tasks for survival Standing

Walking

Suckling colostrum

Consequences of Dystocia

(Schuijt and Tavern ,1994 ; Diesch et al., 2004 ; Barrier et al, 2012)

0.0

00

.25

0.5

00

.75

1.0

0

0 5 10 15analysis time

calving_score = 1 calving_score = 2

calving_score = 3 calving_score = 4

Kaplan-Meier survival estimates

Probability of not achieving sternal recumbency within 15 minutes of birth

Consequences of Dystocia

(Murray et al., unpublished results)

(min)

Pro

bab

ility

0.0

00

.25

0.5

00

.75

1.0

0

0 50 100 150analysis time

calving_score = 1 calving_score = 2

calving_score = 3 calving_score = 4

Kaplan-Meier survival estimates

Probability of not attempting to stand within 15 minutes of birth

Consequences of Dystocia

(Murray et al., unpublished results)

(min)

Pro

bab

ility

0%

10%

20%

30%

40%

50%

60%

Weak Medium Strong

% C

alve

s

Suckling Response

Suckling Response vs Calving Difficulty at 2 Hours

Unassisted

Easy Pull

Hard Pull

Consequences of Dystocia

(Murray et al., unpublished results)

Increased time to achieve sternal recumbency (SR), first attempt to stand and reduced suckling response

Suckling reflex and time to SR have been used as objective indicators of fetal stress and vigor in newborn calves

Calves forcefully extracted took significantly longer to achieve SR and had a lower overall state of vitality

Consequences of Dystocia

(Schulz et al.,1997; Schuijt and Taverne, 1994, Murray et al., unpublished results)

Calves with low vigor have an increased risk of failure of passive transfer due to low volume of ingested colostrum

Failure to get up and drink

Reduced suckling reflex

Up to 74% reduced colostrum intake in calves with fetal distress 12h after birth

Consequences of Low Calf Vitality

(Vermorel, 1989; Furman-Fratczak et al., 2011; Barrier et al., 2012)

In other studies, IgG absorption is reduced in calves with dystocia induced respiratory acidosis

In severely acidotic calves, a 52% decrease in colostrum intake is correlated with a 35% decrease in serum IgG concentration

Significant inverse relationship between venous partial pressure of CO2 at birth and 12h post feeding serum IgG concentration

(Besser et al., 1990; Boyd, 1989; Drewery et al., 1999)

Consequences of Low Calf Vitality

(Boyd, 1989)

Consequences of Low Calf Vitality

Failure of passive transfer may result in:

31% of pre-weaning mortality

30% decrease in pre-pubertal growth rate

30 day increase to first insemination

Produced 2,263 lbs less milk over first 2 lactations

16% decrease in survival to the end of the second lactation

Long Term Health Effects

(DeNise et al., 1989; Faber et al., 2005; Furman-Fratczak et al., 2011)

Outline

Dystocia: effects on the calf

Causes of reduced newborn vitality

Consequences of reduced vitality

Vitality scoring

APGAR (Virginia Apgar)

5 essential assessments:

Appearance (Color)

Pulse (Heart rate)

Grimace (Stimulation)

Activity (Muscle tone)

Respiration

Human Fetal Monitoring

Modified APGAR Scores

Developed for piglet, foal and puppy

Included variables such as heart and respiratory rate, reflexes, mobility and mucous membrane colour

Pups with low vitality scores were less likely to seek the mammary gland and had weaker suckling reflexes and mortality was increased

Piglets with low vitality scores were slower to stand, had more difficulty breathing, had slower heart rates, decreased arterial blood pH and increased partial pressure of CO2, indicating a state of acidemia and hypercapnia

(Randall, 1971; Veronesi et al., 2009)

A modified Apgar score has been assessed in calves in several German studies

Used signs of asphyxia: muscle tone, movement, reflexes, respiration and mucous membrane colour

The modified Apgar score was only marginally correlated with the results of blood-gas analysis

Did not accurately assess the vitality status of the calf, and calves were more appropriately classified into vitality groups based on acid–base status.

Modified APGAR Scores: Calves

(Mulling, 1977; Schafer and Arbeiter, 1995; Herfen and Bostedt, 1999a; Herfen and Bostedt, 1999b)

Hypoxia and acidosis may be indicative of newborn calf vitality

Require expensive, inconvenient and invasive lab tools

A more practical assessment using visual and physical measures can be easily performed on farm

Presence of meconium staining, peripheral edema, cyanosis of the mucous membranes, heart and respiration rates, muscle tone, stimulation reflexes, rectal temperature, time to SR and attempts to stand and suckle (Mee, 2008).

Modified APGAR Scores: Calves

U of G – Calf VIGOR Score Sheet

Outline

Dystocia: effects on the calf

Causes of reduced newborn vitality

Consequences of reduced vitality

Vitality scoring

Methods to improve calf vitality

Assessment of Pain Following Dystocia

Studies have shown that dystocia is one of the most painful conditions in adult cattle

The severity of pain following dystocia in adult dairy cattle was 7, whereas it was only rated 4 in newborn calves

Pain is a subjective experience that is not possible to measure directly

(Huxley and Whay, 2006; Kielland et al., 2009; Laven et al., 2009)

Behaviours and physiological measures that can indicate pain in farm animals: Withdrawal reflex

Movement after birth

Heart and respiration rate

Body temperature

Are calf vitality scores directly correlated with the degree of pain experienced by a newborn calf?

(Molony and Kent, 1997)

Assessment of Pain Following Dystocia

Methods to Improve Vitality

Vitality scores should be used as a decision making tool to assess if further intervention is needed

Conventional intervention methods: Artificial respiration

Respiratory stimulants

Oxygen

Buffer therapy for acidosis

Thermal support

Umbilical treatment

Colostrum from esophageal feeder

(Mee, 2004; Mee, 2008)

Administration of non-steroidal anti-inflammatory drugs (NSAIDs) for alleviation of pain and inflammation

Methods to Improve Vitality

(Hudson et al., 2008)

Currently no published literature on NSAID use in calves

39% of dairy cattle veterinarians in the UK indicated occasional use of NSAIDs in calves following dystocia

66% reported using NSAIDs in some cows following dystocia

Decisions to use analgesia to the cow and/or calf are often influenced by cost

The reported use of analgesics in either cows or calves is probably greater than the actual rate of use

(Huxley and Whay, 2006 ; Hudson et al., 2008; Laven et al., 2012)

Methods to Improve Vitality

Limited usage of NSAIDs may be due to the lack of scientific evidence of the benefits following dystocia

It is clear that the physiological effects of dystocia reduce newborn calf vitality

It is uncertain whether there is pain, since this cannot be directly measured

NSAIDs may improve the time to standing, increase colostrum uptake, improve health, overall calf survival and welfare

Methods to Improve Vitality

(Molony and Kent, 1997; Mee, 2008; Laven et al., 2012)

Outline

Dystocia: effects on the calf

Causes of reduced newborn vitality

Consequences of reduced vitality

Vitality scoring

Methods to improve calf vitality

Study results

Meloxicam for Calf Vitality: Field Trial

A field study to evaluate of the efficacy of meloxicam NSAID therapy for improving newborn calf vigor, success of passive transfer, general health and performance

Objectives:

To evaluate the usefulness of pain management therapy for excessive trauma and enhancement of newborn calf vigor using meloxicam injectable solution.

To determine if newborn calf vigor is associated with calving difficulty, as well as subsequent health and performance.

Non-steroidal anti-inflammatory drug (NSAID)

Anti-inflammatory, anti-exudative, analgesic and fever reducing properties

Approved for use in calves in Canada (20mg/mL)

As an aid in improving appetite and weight gains when administered at the onset of diarrhea (Todd et al., 2010)

For relief of pain following de-budding of horn buds in calves less than 3 months of age (Heinrich et al., 2010)

For the symptomatic treatment of inflammation and pain associated with acute clinical mastitis (Fitzpatrick et al., 2013)

Metacam®

Study Methods

Each calf was scored at birth using calf VIGOR score sheet & a birth record was completed by the farm staff

Calves were randomly assigned to receive either 1.0 cc meloxicam or placebo solution s/c by farm staff

Weekly visits to herds

Study Methods

Blood was collected from all calves 1-7 days of age to measure success of passive transfer

Assess for temperature, weight, height and health scores up to 3 weeks old and again at weaning

In a subset of calves: Blood-gas analysis <2h of age 2nd VIGOR score 1-6h post Tx Suckling response

Calf VIGOR Score - Results

0

1

2

3

4

5

6

7

8

9

Unobserved Observed, butunassisted

Easy pull Hard pull

Vig

or

Sco

re

Calving Difficulty

Calf VIGOR Score - Results

Assistance at Calving Coefficient 95% Confidence Interval P-Value lower limit upper limit Visual Appearance Meconium staining 0.042 -0.047 0.13 0.35 Tongue/head 0.21 0.11 0.30 <0.001

Initiation of Movement Calf movement 0.17 0.025 0.32 0.02

General Responsiveness Straw in nasal cavity 0.21 0.10 0.31 <0.001 Tongue pinch 0.16 0.062 0.27 0.002 Eye reflex 0.043 0.0068 0.093 0.09

Oxygenation Mucous membrane colour 0.16 0.055 0.25 0.002 Tongue length 0.12 -0.023 0.25 0.10

Rates Heart rate 0.18 0.061 0.31 0.003 Respiration rate 0.19 0.084 0.29 <0.001

7.16

7.18

7.2

7.22

7.24

7.26

7.28

7.3

7.32

7.34

7.36

7.38

57.1 68.55 78.3

Pre

dic

ted

pH

at

<2h

pC02 at <2h

Excellent Vigor

Moderate Vigor

Low Vigor

Study Results

Study Results

n

Meloxicam

(Mean±SD)

Placebo

(Mean±SD) P-value

Pre-Tx VIGOR Score 61 6.39±2.71 5.06±2.47 0.41

*Post-Tx VIGOR Score 61 4.71±2.34 5.12±2.37 0.091

Difference 61 -1.68±1.94 0.06±2.66 0.023

Effect of experimental treatment on VIGOR score

*1-6 h post treatment

Calves who received Metacam® following birth had a significant improvement in VIGOR score from the 1st to the 2nd assessment than placebo treated calves, controlling for farm and the time after birth of VIGOR assessment (P=0.023)

Study Results

0

1

2

3

4

5

6

7

8

9

0 5 10 15 20

Seru

m T

ota

l Pro

tein

(g/

dL)

VIGOR Score

VIGOR score was not significantly associated with STP, after controlling for farm and age at blood sampling for STP (β=-0.15; 95% CI=-0.55 to 0.25; P=0.46)

Study Results

Meloxicam (Mean±SD) Placebo (Mean±SD) P-value

n 19 15

Finger Test (1-3)

*Pre-treatment 1.63±0.60 1.53±0.52 0.60

†Post-treatment 2.19±0.68 1.60±0.74 0.024

Difference 0.75±0.79 0.067±0.59 0.014

Manometer Suckling Pressure (psi)

*Pre-treatment 0.57±0.63 0.67±0.51 0.67

†Post-treatment 0.99±1.08 0.67±0.65 0.11

Difference 0.41±0.77 -0.0013±0.46 0.072

Effect of treatment on suckling reflex

*1-2 h from birth †1-6 h post treatment

Study Results

Average Milk Intake (L/d)

Coefficient 95% Confidence Interval P-value

lower limit upper limit

Treatment

Metacam® 0.03 0.0016 0.057 0.039

Placebo ref - - -

Total 8 Week

Health Score

-0.0093 -0.016 -0.0034 0.002

Average # of

Rewarded Visits to

Milk Feeder

2 ref - - -

4 0.080 0.050 0.11 <0.001

5 0.055 0.0093 0.10 0.019

Farm

2 0.61 0.53 0.69 <0.001

1 ref - - -

Study Results

4

4.5

5

5.5

6

6.5

7

Milk

Inta

ke (

L/d

)

Meloxicam

Placebo

N=124 N=124

Study Results

0

0.5

1

1.5

2

2.5

3

3.5

4

4.5

5

Observed butUnassisted

Unobserved Assisted

We

igh

t G

ain

in W

ee

k 1

(kg

)

Calving Assistance

Metacam

Placebo

n=63

n=166

n=150

n=92

n=100

n=55

Study Results

Treatment Metacam® -0.36 -0.64 -0.073 0.014 Placebo ref - - -

Season of Birth

Spring 1.21 0.082 2.34 0.036 Summer -0.16 -0.57 0.25 0.44 Winter 1.40 1.06 1.74 <0.001 Fall ref - - -

Time colostrum fed after birth

<2hrs ref - - - 3-4 h -0.15 -0.54 0.25 0.43 5-6 h -0.27 -0.98 0.45 0.46 7-12 h 1.20 0.21 2.10 0.018

Total Health Score

Coefficient 95% Confidence Interval lower limit upper limit

P-value

Outline

Dystocia: effects on the calf

Causes of reduced newborn vitality

Consequences of reduced vitality

Vitality scoring

Methods to improve calf vitality

Study results

Biomarker for calf vitality and long-term health

Haptoglobin

Major bovine acute phase protein

Produced in response to a bacterial or viral challenge

Works by binding free hemoglobin in plasma to reduce the pro-oxidative and pro-inflammatory stress associated with hemolysis

Can be used as a quantifiable indicator of tissue damage, including infection, neoplasia or trauma

(Gruys et al., 1994; Murata et al., 2004; Petersen et al., 2004)

Haptoglobin – Indicator of Inflammation at calving

0

0.05

0.1

0.15

0.2

0.25

Observed butUnassisted

(N=146)

Unobserved(N=533)

Easy Pull(N=356)

Hard Pull(N=44)

Malpresented(N=23)

Surgery(N=7)

Me

an H

apto

glo

bin

(g

/L)

Assistance at Birth

Haptoglobin – Indicator of Health

0

0.05

0.1

0.15

0.2

0.25

0(N=186)

1(N=629)

2(N=227)

3(N=65)

≥4 (N=43)

Me

an H

apto

glo

bin

(g/

L)

Event 1 Health Score

P<0.001, accounting for farm as a random effect

0

0.02

0.04

0.06

0.08

0.1

0.12

0.14

0.16

0.18

No (N=890) Yes (N=312)

Me

an H

apto

glo

bin

(g/

L)

Treated for BRD in 1st 4 Months

P<0.05, accounting for farm as a random effect

Haptoglobin – Predictor of Health

0

0.05

0.1

0.15

0.2

0.25

No (N=1070) Yes (N=132)

Me

an H

apto

glo

bin

(g/

L)

Treated for Diarrhea in the 1st 4 Months

P<0.001, accounting for farm as a random effect

Haptoglobin – Predictor of Health

0

0.05

0.1

0.15

0.2

0.25

No(N=1158)

Yes(N=55)

Me

an H

apto

glo

bin

(g/

L)

Dead

P=0.001, accounting for farm as a random effect

Haptoglobin –Predictor of Mortality

Mortality Odds Ratio 95% CI P-value

Lower Limit Upper Limit

Hp (g/L) 4.29 1.07 17.18 0.04

Passive Transfer

Pass (>5.4g/dl) Ref

Intermediate (5.2-5.4g/dl) 0.43 0.13 1.47 0.18

Fail (<5.2g/dl) 2.22 1.2 4.11 0.01

Treated for BRD once or more

during study period

No Ref - - -

Yes 2.77 1.56 4.92 0.001

Treated for scours once or more

during study period

No Ref - - -

Yes 3.26 1.72 6.18 <0.001

Treated for other disease once

or more during the study period

No Ref - - -

Yes 2.06 1 4.22 0.049

Haptoglobin –Predictor of Mortality

Conclusions

Effects of dystocia: pain, fractures, trauma, hypoxia & impaired thermoregulation lead to reduced calf vigor & failure of passive transfer

Newborn calf vitality assessed through modified APGAR scores are well correlated to the degree of calving assistance using practical on farm measures

NSAIDs following dystocia my improve calf vitality, health and growth

Haptoglobin may be a biomarker for inflammation at calving and subsequent risk of morbidity and mortality

Acknowledgements

Advisory committee:

Ken Leslie – Professor Emeritus

Todd Duffield – Professor, Dairy Health Management

Derek Haley – Assistant Professor, Animal Welfare

David Pearl – Associate Professor, Epidemiology

Doug Veira – Senior Scientist, AAFC, Agassiz BC

Kathleen Shore – Nutritionist, Grober/New-Life Mills

Funding & support provided by:

Questions?