ANS 404- Lecture 5 & 6 (Calf and replacement Heifer Management)

Typical timeline of a cow

Calf to heifer to cow

What do we focus on for calves?

Growth

Health

What do we focus on for heifers

Reproduction

Growth

What do we focus on for cows?

Production

Reproduction

Weight of cows at birth

40-60 lbs small breed

70-100 lbs large breed

Physiology of a neonatal calf

Monogastric, slowly develops a rumen

Esophageal groove

A groove present in young ruminants that allows milk to bypass the rumen, avoiding fermentation.

Why may a calf be shivering?

It is under cold stress (<60 F)

Colostrum

The mother's first milk

very important to cattle

What does colostrum provide?

Immunoglobulin G proteins

IgG proteins

Activates a calf's immune system

Provides localized gut immunity

When should be colostrum be given to calves?

Within the first hours of birth (no more than 6)

How is the immunoglobulin absorption affected by the time at which colostrum is given?

Absorption decreases at time increases

What should the quality of IgG be?

>50g of IgG/L of colostrum

How can the quality of IgG content be measured?

Through a colostrumeter or refractometer

Recommendations for feeding colostrum

1 gallon

High quality

Directly after birth

Methods of feeding colostrum

Bottle

Esophageal feeder

Bedding for newborns

Clean, dry bedding

Navel dipping

antiseptic solution to prevent infection

- iodine dip

- Vatericyn spray

What does scours cause?

GI distress

What can a runny/dry nose or coughing indicate?

Seen together can indicate respiratory infection

(check resp. rate >1 breath/2 s)

What can a fever (temp above 104 F) indicate?

Infection

What can a swollen left side indicate?

Bloat

What can limping indicate?

Injury or foot rot

What can skin problems indicate?

Parasite or fungus infection

How should vaccinations be handled in calves?

Through the consultation with a veterinarian

General 5-way vaccination at 6 weeks

Infectious bovine rhinotracheitis (IBR)

Bovine respiratory syncytial virus (BRSV)

Parainfluenza-3 virus (PI3)

Bovine viral diarrhea (BVD)

Clostridial spp.

How should vaccinations be timed?

Space vaccinations out and away from

timing of other procedures to reduce

stress and improve growth rates

Debates in calf management

Milk Source?

Milk Volume?

Feeding Method?

Calf Starter?

Dehorning?

Housing?

Potential milk sources for calfs

Milk replacer and whole milk

Expenses of milk replacer vs whole milk

replacer: Price/50lb bag

Whole: Milk price/cwt

Nutrients of milk replacer vs whole milk

replacer: consistent

Whole: fluctuating

Improvements of milk replacer vs whole milk

replacer: Available with additional cost

Whole: Limited to on-farm resources

Safety of milk replacer vs whole milk

replacer: dried powder

whole: Pasteurization with additional equipment

Is whole milk more expensive or less expensive than replacer?

It depends on the market value of milk at the time, so it can fluctuate

Approximately how much may a bag of milk replacer cost?

50-80 $

($1.6/lb - $89.60/calf)

Restricted vs Ad Lib Milk volume management

Restricted: Once or twice a day feeding

Ad Lib: Specialized equipment

Restricted vs Ad Lib Milk expense

Restricted: Less milk; decreased cost

Ad Lib: More milk; increased cost

Restricted vs Ad Lib Calf starter intake

Restricted: More calf starter; more developed rumen

Ad Lib: Less calf starter; less developed rumen

Restricted vs Ad Lib Growth

Restricted: Less DE; less gain

Ad Lib: More DE; more gain

Bottle vs Bucket Feeding method training

Bottle: Natural reflex

Bucket: Required

Bottle vs Bucket Feeding method sanitation

Bottle: Difficult; may require additional equipment

Bucket: Easier for manual cleaning

Bottle vs Bucket Feeding method volume

Bottle: Limited to 2 qt each; multiple feedings/bottles required

Bucket: Easier to adjust feeding amounts

Bottle vs Bucket Feeding method performance

No Difference

What breed cannot train to buckets?

Swiss

Calf starter

high energy, high protein concentrate feed for dairy calf

- can be in pellets or hay/pasture

Pellets vs hay digestibility

Pellets: Greater fermentation

Hay: Less digestibility

Pellets vs hay expense

Pellets: Grains increase cost

Hay: Grasses decrease cost

Pellets vs hay VFAs

Pellets: More development; easily digestible sugars

Hay: Fiber; less abnormal papillae growth

Pellets vs hay modifications

Pellets: Textured

Hay: Fine chopped; vegetative state

What regions use more pellets for calf starters? Hay/Forage?

The US utilizes pellets, European countries and organic dairies utilize hay/forage

Methods of disbudding

Hot iron, chemical, tube, genetis

Hot Iron disbudding

Deadens nerve

- can cause burning

Chemical disbudding

Destroys support cells

- can cause itching pain, can get into eyes

Tube disbudding

Cuts under horn bud

- results in an open wound

Genetic disbudding

Select polled animals

What should be used with any disbudding method?

both short term and longer term pain relief

could use both a lidocaine block and banamine

When should disbudding occur?

earliest in life for less stress

Why are all cows not bred to be polled?

There are more important traits

Housing options for pre-weaned calves

Individual hutches and group housing

- parahousing can offer a solution

Safety of Individual hutches vs group housing

Individual hutches: Quarantined

group housing: Easy spread of disease

Socialization of Individual hutches vs group housing

Individual hutches: Additional stress during weaning

group housing: From birth

Monitoring of Individual hutches vs group housing

Individual hutches: Easy health checks based on changes in behavior

group housing: Difficult to isolate sick calf

Feeding of Individual hutches vs group housing

Individual hutches: Consistent individual intake

group housing: Ad lib feeding capability

Indoor vs outdoor housing weather

indoor: Protected; possible heating/ cooling

outdoor: Exposed; minimal shelter

Indoor vs outdoor housing ventilation

indoor: Specifically built; can be a major problem

outdoor: Natural (Free)

Indoor vs outdoor housing facilities

indoor: Limited number of stalls

outdoor: Flexible in numbers; mobile

Indoor vs outdoor housing expense

indoor: Building & running facilities

outdoor: Calf loss; additional labor

Typical age of weaning

Typical range is 42-63 days of age at weaning

where are calves moved after weaning?

calf-rearing facility

diet of post-weaned calves

Forage & grain diet

30% Cottonseed hull-based TMR

At what BW are heifers bred

What breeds are bred youngest? oldest?

Jerseys breed youngest, Swiss oldest

When do we want a cow to have her first calf?

at 2 years old

Heifer replacement goal

The goals of a dairy replacement management program are to rear heifers at a low economic and environmental cost without compromising future lactation performance.

What should the growth curve of heifers look like?

Should be consistent

Target growth for holstein heifers in prepubertal period

BW gain: 1.6 to 1.8 lbs/d

Wither height: 1.4"/month

Target growth for holstein heifers in breeding period

BW: 780 lbs

49 to 50" wither height

BCS: 3.0 - 3.5

Target growth for holstein heifers 10 months to calving

BW gain: 1.8 to 2.0 lbs/d

Wither height: 0.5 to 0.6"/month

Target growth for holstein heifers prepartum

BW: 1350 to 1400 lbs pre-calving or 1200 lbs after calving

Height: 54-56" at the withers

BCS < 4.0 at calving (3.25 - 3.75)

What do higher ADG rates in pre weaned calves lead to?

better mammary gland development

What do lower ADG rates in calves at puberty lead to?

better mammary gland development

What are the highest expenses for heifers?

1) feed

2) labor

Goals in cost for replacement heifers

1. Obtain a return on your investment of 2:1 by the time the heifer is culled from the milking herd

2. Heifer must make the dairy enterprise a profit of $2000-$2500 before she leaves the herd.

What percentage of a herds production cost does raising replacements account for?

20%

When will you begin to see a return for investment on a heifer?

You have approximately 1.5 lactation's to return a profit on your investment

steps to maximize return on investmenr

1. Reduce your total input cost per heifer.

2. Get heifers into the milking herd sooner.

3. Increase milk production in the 1st and 2nd lactation.

4. Manage the heifer environment and feeding program to maximize lean growth from weaning to calving

what is the goal when determining the number of replacement heifers needed?

to replace lactating cows

Needs for replacements depend on:

1. Cow culling rate

2. Rate of expansion of the dairy herd

Heifers leaving depend on:

1. Mortality rate

(from birth to first calving)

2. Culling rate

(either voluntary or involuntary culling)

3. Age at first calving

What does the number of heifers available depend on?

Herd size

Calving interval

Sex ratio

Calf mortality

age at first calving

what does an increased calving interval result in?

a decreased number of replacements needed

assumed sex ratio of calves

50:50

What % should calf mortality be kept under?

10%, ideally 5%

What does an increased mortality rate result in?

a decreased number of replacements

When should cows ideally be freshen?

by 24 months, goal is to have first calf at 2 years

what is the increase in annual replacement rate every month after a cow is 24 months of old and not getting bred?

4.2%