Dairy calf nutrition

Question 1

when do you want heifter to have first calf

Answer 1

22-24 mo old

Question 2

how soon should you remove calf from dam

Answer 2

within 30-60 min

Question 3

when do you wean calf

Answer 3

8 weeks

Question 4

5 Cs of successful calf rearing

Answer 4

• colostrum
• calories (nutrition)
• comfort
• cleanliness
• consistency

Question 5

5 Qs of colostrum management

Answer 5

• quality of colostrum fed
• quantity of colostrum fed
• quickness in providing
• squeaky clean (bacterial contamination)
• quantifying the results (monitoring)

Question 6

what type of placenta do cows have

Answer 6

syndesmochorial –> immunoglobins can’t cross to fetus

Question 7

when do you call it FPT

Answer 7

calf serum IgG < 10mg/ml

Question 8

benefits of successful passive transfer (4)

Answer 8

• reduced treatment and mortality rates
• improved growth rate and feed efficiency
• decreased age at first calving
• increased 1st and 2nd lactation milk production

Question 9

goal for colostrum IgG

Answer 9

=> 50g/L

Question 10

factors not under management control affecting colostrum quality

Answer 10

• breed (higher in colored breeds)
• parity (higher in older cows)
• prepartum leaking

Question 11

factors under management control affecting colostrum quality

Answer 11

• dry cow nutrition
• stress during dry period
• vaccination during dry period
• clinical mastitis
• time to first milking (ASAP)
• dry period length (lower if <3 weeks)

Question 12

when should you harvest colostrum from dam

Answer 12

with 1-2 hours (6 hours max)

Question 13

ways to measure colostrum quality

Answer 13

• colostrometer (room temp only)

- brix refractometer (more expensive)

Question 14

colostrum quantity recommendation

Answer 14

feed 10% of BW at first feeding (4L in average 90lb/43kg calf)

Question 15

when does calf gut closure finish

Answer 15

by 24 hours

Question 16

goal for quickness of colostrum feeding

Answer 16

feed within 1-2 hours (6 hours max)

Question 17

consequences of microbes in colostrum

Answer 17

• bacterial interference with IgG (more bacteria = lower IgG)
• pathogens in colostrum may cause dz

Question 18

3 major sources of colostrum contamination

Answer 18

• infected gland or fecal contamination from teat skin
• contaminated collection, storage, or feeding equipment
• bacterial proliferation in stored colostrum

Question 19

storing colostrum properly

Answer 19

• feed in less than 1-2 hours
• refrigerate for less than 48 hours
• freeze ASAP

Question 20

on-farm monitoring of serum total protein to evaluate colostrum program

Answer 20

• bleed 12 normal calves between 24hrs-7days old
• test serum with refractometer
• goal: => 90% have TP => 5 g/dl OR => 80% have TP => 5.5 g/dl

Question 21

goals of calf nutrition program

Answer 21

• double birth weight by 56 days of age

- develop functional rumen so can be weaned off milk by 7-8w old

Question 22

3 phases of calf development

Answer 22

• pre-ruminant phase (birth –> 3-4 weeks)
• transition phase (3-4 weeks –> weaning)
• ruminant phase (weaning –> 225lbs+)

Question 23

pre-ruminant phase

Answer 23

• no functional rumen
• can’t digest solid feed
• abomasum is main compartment
• diet: milk, calf starter, water

Question 24

how much milk/milk replacer to feed to preweaned calves

Answer 24

• summer: 2-3 quarts BID

- winter: 3-4 quarts BID

Question 25

feeding starter grain/water to preweaned calves

Answer 25

- free choice starter grain after 3d old | - free choice water after 3d old

Question 26

abomasal digestion in preweaned calves

Answer 26

- milk clots - chymosin (rennin) acts on casein - pepsin, HCl digest milk clot

Question 27

intestinal digestion in preweaned calves

Answer 27

- sugars poorly digested (except lactose) - starches/non-lactose disaccharides not digested until 3-4w old - pancreatic enzymes increase gradually

Question 28

transitional phase

Answer 28

- diet: milk, grain, water - begin developing functional rumen (takes a minimum of 3 weeks) - grain promotes production of butyric/propionic acid

Question 29

what does feeding forage in transitional phase promote

Answer 29

acetic acid promotion --> doesn't help with rumen development

Question 30

post-weaning diet

Answer 30

- 1-2 weeks: grain, water | - 3+ weeks: grain, water, forages

Question 31

fat sources

Answer 31

- lard (best, most economical) - tallow - vegetable (most expensive)

Question 32

pros of feeding pasteurized non-saleable milk

Answer 32

- reduce pathogen transmission - improve rate of gain - improved calf health - improved economic efficiency - utilization of non-saleable product

Question 33

cons of feeding pasteurized non-saleable milk

Answer 33

need more intensive management and monitoring (and a pasteurizer)

Question 34

calf thermoneutral zone

Answer 34

10-20C, 50-70F

Question 35

strategies to improve energy status in cold weather

Answer 35

- increase caloric intake (increase volume/number of feedings, add fat) - decrease energy losses (keep dry, prevent drafts, insulation, heat, free choice starter grain and water, health management)

Question 36

what starter qualities do calves prefer

Answer 36

- textured - avoid fines, dust - fresh - palatable

Question 37

importance of free choice water

Answer 37

- promotes rumen development (microbes, greater feed intake) | - essential to maintain hydration status (heat stress, illness)

Question 38

water guidelines

Answer 38

- winter: warm water for 1 hour after feeding then dump - summer: check mid-day, offer 3rd feeding if needed - free choice essential if feeding accelerated milk replacer program

Question 39

weaning guidelines

Answer 39

- reduce stress by spreading out changes - before weaning, should be eating starter for 3+ weeks at least 2lbs/day - moving to groups