dr. rachel j. e. stewart bvsc, mvsc, phd cvs, uz colostrum management in calves: is it really a...

Dr. Rachel J. E. StewartBVSc, MVSc, PhD

CVS, UZ

COLOSTRUM MANAGEMENT IN CALVES: Is it really a matter of life or death?

Table 1 Heifers needed to keep herd size at 100

Cull rate %

Age at first calving 22mnth

Age at first calving 24mnth

Age at first calving 26mnth

Age at first calving 28mnth

Age at first calving 30mnth

Age at first calving 32mnth

Age at first calving 34mnth

Age at first calving 36mnth

20 40 44 48 51 55 59 62 66 22 44 48 52 56 61 65 69 73 24 48 53 57 62 66 70 75 79 26 52 57 62 67 72 76 81 86 28 56 62 67 72 77 82 87 92 30 61 66 72 77 82 88 94 99 32 65 70 76 82 88 94 100 106 34 69 75 81 87 94 100 106 112

THE OBJECTIVE OF FEEDING COLOSTRUM

To maximize the defence capacity of the newborn calf as soon as possible after birth. (specific and aspecific)

Calves are born agammaglobulinaemic: no antibodies and no immune system due to the type of placentation (syndesmochorial)

COLOSTRUM COMPOSITION

Enzyme inhibitors Bacteriostatic proteins

Lactoferrin Lysozyme Lactoperoxidase system

Leukocytes Immunoglobulins

COLOSTRUM COMPOSITION

Item 1st Milking after calving

2nd Milking after calving

3rd Milking after calving

Milk

Total solids 23.9% 17.9% 14.1% 12.9% Protein 14% 8.4% 5.1% 3.1% Antibodies 48 mg/ml 25 mg/ml 15 mg/ml .6 mg/ml Fat 6.7% 5.4% 3.9% 3.7%

LEVEL OF PASSIVE IMMUNITY

Ig G absorbed depends on: Amount of ingested colostrum Concentration of Ig G in colostrum Absorption efficiency of calf gut

Depends on the age at first feeding Method of colostrum feeding

Absorption of Colostrum Intestinal cells of the newborns digestive

tract are able to engulf large molecules such as Ig in vesicles for a period of approximately 24 hours after birth

Peak ability to engulf occurs within the first 6 hours after birth and declines until 24 hours when it stops altogether

The vesicles cross the cell and release their contents into the blood circulation via the lymphatic system

Transport of Ig between blood and intestine

After absorption of the Ig’s into blood the Ig's are released continuously from blood into the lumen of the intestine to provide local immunity to the gut

High serum concentrations of serum Ig are needed to maintain this cycle to ensure adequate levels in blood and gut at time of closure

Serum Ig concentration

Calf serum Ig concentration peaks at 24 to 36 hours after birth.

Thereafter serum concentrations gradually decline to minimal between 15 and 28 days of age

There is a gradual but steady increase in serum isotypes from 4 to 7 weeks

Mean Serum Concentrations of Ig at different ages

Failure of Passive Transfer

A serum Ig G concentration of <1000mg/dl by 48 hours has been

defined as failure of passive transfer

Reasons for failure of passive transfer

DAM: low colostral Ig CALF: weak calves due to dystocia,

premature birth, infections , suckling calves.

MANAGEMENT: first feeding too late or amount too small - CONCENTRATION * VOLUME

Colostrum feeding 10% of birth weight within 1 hour of birth

5% of birth weight at 6 hours after birth

5% of birth weight at 12 hours after birth

5% of birth weight at 24 hours after birth

Colostrum Quality CHECK

Dry off strategy (use of dry cow antibiotic) Disease history Length of dry period Parity Colostrum leakage Prepartum milking Premature calving Dystocia Colostrum yield

Risk Factors IgG intake

COW FACTORS: yield >8kgs, front quarter colostrum, parity of dam, heifer calves, dystocia, diseases

MANAGEMENT FACTORS: prepartum milking, milk leaking, time/ amount 1st colostrum gift, hygiene, maternity pen, caretaker

Colostrometer

Use first milking colostrum Test colostrum at room temp. Most effective in identifying poor

quality samples Specific gravity > 1.045 indicative

of IgG conc of > 50 mg/ml

IgG concentration in colostrum 48.2 (20 – 100) mg/ml (Pritchett et al 1991) 66 (28 – 115) mg/ml (Quigley et al 1994) 76.2 (26 – 110) mg/ml (Rajala and Castren

1995) At least 100g of pure IgG must be ingested

at each of the first two colostrum feedings to achieve a blood conc of at least 1000 mg/dl to reduce the incidence of disease and death

Serum Ig Tests Done on calves

Zinc turbidity test (Ig): Gel/ turbidity if adequate

Refractometer (total protein): 5.2g/dl and above

Sodium sulfite precipitation test (Ig) Latex agglutination test (Ig) NA Radio immunodiffusion test kit (Ig) NA Gluteraldehyde test (Ig and fibrinogen)

Storage of Colostrum

Room temperature for 1 day Acidified (5 gr proprionic acid or

lactic acid) at 5 C for 6 weeks Deep frozen (-20C) for more than a

year Not in frost free freezers Thaw in warm water (<60C)

Ig and disease

An overwhelming pathogen challenge or environmental conditions that are poor will overwhelm even very good passive transfer

3 Zimbabwean Farms Workers and Owners knew the correct

method Tested serum total protein of all calves

between 2 and 14 days of age. Over 50% below 5.2 All 3 farms had problems with calf

scours, pneumonia and death Instituted improved colostrum

management

3 Zimbabwean Farms

All 3 farms calves tested on a regular basis to check on compliance

2 farms constant passes 1 farm one set of over 50% failure

again one month into new regime No failures over 25% since

3 Zimbabwean Farms

One farm greatly reduced scours and coughing, improved weaning weights

Another farm no more umbilical hernias and can’t remember the last time they treated a sick calf

Last farm no more scours and greatly reduced pre weaning mortality

Post Calving to Weaning

Disinfect umbilical cord Move to clean well ventilated pens/

hutches Colostrum for 5 days Feed good clean milk at 39C at to

15% of birth weight divided into two feeds per day

Post Calving to Weaning

Clean water from day one all day Calf meal of good quality from day 4 Good quality hay from week 2. Move hutches or clean out pens at

least every three days. Check feed intakes, can be weaned

when eating more than 2.5% of birthweight per day