Dairy Neonatology and Replacement Programs

emily_scholz1

What is the typical heifer cycle in the U.S.?

Day 1 - Day 2 to weaning - Weaning - After weaning - Breeding - Pregnancy - first calving

Day 1 heifer cycle

removed from dam and fed cololstrum

Day 2 to weaning heifer cycle

• Reared on whole milk or milk replacer with access to calf starter

• Individual, paired, or group housing

Weaning heifer cyle

• 45 (early) to 70 (late) days of age

• Moved to groups if not already

After weaning heifer cycle

• Outdoor / indoor group housing

• goal reach breeding size at 11-13mo

Breeding heifer cycle

• outdoor or indoor housing

• goal maintain good repro performance so calving goal is reached

Pregnancy heifer cycle

Maintain growth and body condition

First calving heifer cycle

• Moved to prepartum housing and diet 3–6wk prior to calving

• goal calve by 24mo of age at 85% mature size

What is the most expensive age period? Compared to feed and labor?

birth to weaning

2nd/3rd to feed ± labor

Goals of heifer rearing

• keep heifers healthy

• be cost effective

• reach first calving at around 24mo and 85% mature body size

When are calves weaned?

• early: 45d

• Late: 70d

At what age do you want to reach breeding size?

11–13mo

When should you move pregnant cows to prepartum housing and diet?

3–6wk before calving

Goal for first calving?

24mo

What are the top 2 high risk periods for calf mortality?

• 1st 2 weeks (congenital, birth trauma, diarrhea, sepsis)

• Peri-weaning (resp dz)

• MOST disease in the first three months

What are the important causes of morbidity in the first 2 days?

• Congential

• premature calves

• calving trauma

What are the important causes of morbidity from 3–21 days?

• Infectious calf diarrhea

• sepsis

• navel infection

What are the important causes of morbidity from 21d to weaning?

• resp disease

• otitis media (Mycoplasma bovis)

What are the important causes of morbidity after weaning?

• Respiratory disease

• Otitis media (Mycoplasma bovis)

• Coccidiosis

• Bloat, digestive upset

What are the most important causes of morbidity from 3mo to 5mo?

• resp disease

• pinkeye

• coccidiosis

• nematode parasitism

What are the most important causes of morbidity from 6mo to breeding?

• pinkeye

• injury

• Parasitism, heifer mastitis

What are the important causes of morbidity from breeding to late gestation?

• heifer mastitis

• abortion

What are the important causes of morbidity during calving?

• dystocia

• udder edema

5 C’s of dairy calf raising

• colostrum

• cleanliness

• comfort

• calories

• consistency

What has a tremendous impact on the health and vigor of the calf?

nutrition and health of the calf

How should the maternity area be?

clean and dry

Wet, contaminated maternity areas increase risk of?

• navel infection

• septicemia

What are the primary concerns regarding newborn calves during the first few hours of life?

• Colostrum

• navel health

• clean environment

T/F: ruminants have transplacental transfer of antibodies

False, passive transfer is through colotrum

Endogenous Ab prod. develops over how long?

2-3mo

Maternal antibody is absorbed ? is essential to prevent disease

colostrum

what are the two main determinants of success or failure of a colostrum program?

• mass of immunoglobulin fed (quality X quantity)

• time (hours of age at first feeding)

If a calf receives ? of immunoglobulin, she will rarely have FTPI

>280g

Good quality colostrum Ig concentration

>50 g/L

How much good quality colostrum must a calf receive?

5–6L

How much excellen quality colostrum must a calf receive?

4L

How can Ig be measured?

• colostrometer (specific gravity)

• Refractomoter (total solids)

T/F: efficiency of absorption is 100% at 0 hours

False - 30-50% (they will never absorb all that is given)

When does gut closure occur?

Begins at birth —- halfway at 6-8hrs —- complete by 24hrs

What is the goal for the time of feeding colostrum?

100% of calves first fed within 2 hours of birth (ASAP)

What is the goal for bacteria in colostrum?

• <100,000 CFU/mL total bacteria

• <1,000 CFU/mL coliforms

There is a relationship between serum total protein and what?

risk of mortality

What is the cutoff of serum total proteins for adequate passive of transfer?

5.8 g/dL

What is the serum TP goal after drinking colostrum?

≥ 5.8 g/dL at 2-8d of age in >70% of calves

5 Qs of colostrum management

• quality

• quantity

• quickness

• squeaky clean

• quantify

High bacteria count in colostrum is associated with what?

Increased risk of neonatal diarrhea and sepsis

Describe the practical plan for colostrum feeding

4L in the first 2hr after birth

Why not rely on calf nursing on dam for colostrum?

• No control over quality

• No control over volume

• No control over disease (esp. Johne’s disease)

Describe navel disinfection process

• Saturate navel within 2 hours of birth (earlier if possible) with chlorhex soln. or povo/iodine soln

• repeat when calf is put in pen

• repeat 12-18hr later

<48 hours after birth (neonatal), calves should be…?

• ID’d with a unique ID system (ear tag)

• Weighted

• Placed in preweaning calf housing (clean, dry, good ventilation, individual)

During the pre-weaning period, what is the goal for growing the calf?

1.8 lbs/d

How much liquid, on average, should preweaned calves be fed?

• 2.5 - 4L, 2-3x per day —- 6-8L/d (for Holstein)

• feed more in cold weather (<45ºF)

T/F: All liquid feeding equipiment must be cleaned and sanitized at least once per week

False, after every use

Water should be offered to pre-weaned calves beginning when?

day 1

High quality grain (calf starter) should be offered to pre-weaned calves beginning when?

day 2-3

describe the ideal calf housing

• clean, dry, comfortable to lay

• good ventilation while minimizing drafts in cold weather

• adequate space

• shelter from elements

• ability to see and hear other calves

Describe calf housing: hutches

• paired or single

• reduces direct contact

• placei n long rows, hutch-wdith apart

• in wet weather, hutches should be moved every 3–4 days

• in dry weather with no diarrhea, hutches should be moved every 7 days

• Clean the area

• Mow the grass to prevent flies

Describe the calf housing: barn with pens or hutches

• individual pens in the barn

• use a design that prevents direct contact

• clean pens and floor only as necessary to limit aerosolization of pathogens

• jutches under a roof are a great option in FL —- protection from weather, allows fan cooling

Describe calf housing: group

• Combined with automatic feeding systems for large amounts of milk delivery

• <10-12 per pen (smaller group = better health)

• Increased risk of sharing pathogens

Describe 2 methods of milk delivery in group housing

• Ad lib = cannot control besides just turning milk off totally

• Mechanized = controlled by computer (calf gets scanned and controlled how much they get)

What supplements do pre-weaned calves need?

• Vitamin E and Se

• Vitamin A and D (if feeding whole milk instead of replacer

How often do you want to observe pre-weaned calves for disease?

Twice per day

Disbudding destroys what?

Corium

Describe debudding 1-7d?

Caustic paste

Describe debudding at <2mo

Hot iron

Describe disbudding at 2-4mo

• hot iron

  • amputate

Describe debudding at >3mo

Amputation (surgical, open or closed, barnes dehorner)

T/F: dehorning is not painful

False - painful, but greatly reduced when analgesia is provided (cornual nerve block)

What is the weaning age?

6–10 weeks (42–70 days)

How much calf starter should calves be eating at the start and end of weaning?

• start = 2lbs/d

• end - 5lbs/d

What are the 2 main weaning strategies? Best?

• Abrupt weaning

• Gradual weaning (better, stay healthier, avoid NEB, maintain growth)

When shoulod you move post-weaning to 5mo old calves from individual to group housing?

1-3 weeks post weaning

How much should be fed to post-weaning to 5mo old calves?

feed for average daily gain of 1.8 lbs/d (keep on same calf starter until about 3-4mo old to have more forage and less conc.)

Describe what to do post-weaning to 5mo old calves

• ideal stocking rate = <15 calves per pen for 1st mo (can increase when older

• maintain fly control

• vaccinations

• deworming

• weigh at 4mo to monitor performance

  • remove extra teats

What is stocking rate of heifers from 6mo to breeding (13mo)?

no more than 75 heads/pen

when to deworm?

8-9mo

From 6mo to breeding heifers should continue to grow at what rate?

1.8lbs/d

What is the goal of heifers for first breeding (11-13mo)?

>750 lbs (>51”) and at least 11mo old

Why do you want heifers to be 750 lbs and >51” at breeding?

• decrease risk of dystocia

• make sure not growing a ton during first lactation because that will decrease milk production

What are the procedures done to pre-breeding heifers (11-13mo)?

• Vacc. with IBR/PI3/BVD/BRS/Lepto

• Recheck udder for abnormalities

• Weigh

• Deworm

• Leave alone for 3wk and then move to breeding pen

What flies increase risk of heifer mastitis?

Horn fly

What flies are associated with Moraxella bovis (pink eye)?

face and house fly

When are pregnant heifers dewormed and vaccinated for lepto?

70d gestation

“Springing” heifers

• move heifers to pre-cavling area 3-6 weeks pre-calving

• observe for udder edema (more preone than cow, less venous return)

• observe for dystocia

Reproductive performance is dependent on what?

• Estrous detection

• Conception rate

What are the most common blood-borne diseases? Control?

• Bovine leukemia virus and anaplasmosis

• Use new needle every animal

• change rectal sleeves between each animal (minor)

• clean and disinfect all reusable equipment that may be blood contaminated

What are core vaccines for heifers?

• IBR, PI3, BRSV

• BVDV (immunosuppressive)

• Clostridium

• Lepto

What calf diarrhea pathogens should cows be vaccinated in late gestation to provide protection for calves?

• E. coli

• rotavirus

When should clostridial bacterin (7 or 8 way) be given?

• 1st dose = pre-weaning

• 2nd dose = 3-8 wks after (could be pre- or after-weaning)

• annual booster

When should dairy heifer calves be vaccinated for respiratory viruses?

• intranasal modified live for IBR, PI3, BRSV = 1st month of life

• systemic MLV vaccine (BVD, IBR, PI3, BRSV) = wait until >1mo

• booster at 6mo

• annual booster

When should dairy heifer calves be vaccinated for leptospira?

• 5-way ± hardjo-bovis

• 2 dose 3-6wks apart prior to breeding (generally 4-6mo)

• booster at least annually, q6mo in high risk

Brucella abortus vaccination of dairy heifers

• not required by USDA

• up to each state

• MLV vaccine licensed for use in female cattle 4-12mo

T/F: it is ok to vaccinate cows if temp is over 85º

False, impaired immune response