Dairy calf nutrition Flashcards
when do you want heifter to have first calf
22-24 mo old
how soon should you remove calf from dam
within 30-60 min
when do you wean calf
8 weeks
5 Cs of successful calf rearing
- colostrum
- calories (nutrition)
- comfort
- cleanliness
- consistency
5 Qs of colostrum management
- quality of colostrum fed
- quantity of colostrum fed
- quickness in providing
- squeaky clean (bacterial contamination)
- quantifying the results (monitoring)
what type of placenta do cows have
syndesmochorial –> immunoglobins can’t cross to fetus
when do you call it FPT
calf serum IgG < 10mg/ml
benefits of successful passive transfer (4)
- reduced treatment and mortality rates
- improved growth rate and feed efficiency
- decreased age at first calving
- increased 1st and 2nd lactation milk production
goal for colostrum IgG
=> 50g/L
factors not under management control affecting colostrum quality
- breed (higher in colored breeds)
- parity (higher in older cows)
- prepartum leaking
factors under management control affecting colostrum quality
- 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)
when should you harvest colostrum from dam
with 1-2 hours (6 hours max)
ways to measure colostrum quality
- colostrometer (room temp only)
- brix refractometer (more expensive)
colostrum quantity recommendation
feed 10% of BW at first feeding (4L in average 90lb/43kg calf)
when does calf gut closure finish
by 24 hours
goal for quickness of colostrum feeding
feed within 1-2 hours (6 hours max)
consequences of microbes in colostrum
- bacterial interference with IgG (more bacteria = lower IgG)
- pathogens in colostrum may cause dz
3 major sources of colostrum contamination
- infected gland or fecal contamination from teat skin
- contaminated collection, storage, or feeding equipment
- bacterial proliferation in stored colostrum
storing colostrum properly
- feed in less than 1-2 hours
- refrigerate for less than 48 hours
- freeze ASAP
on-farm monitoring of serum total protein to evaluate colostrum program
- 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
goals of calf nutrition program
- double birth weight by 56 days of age
- develop functional rumen so can be weaned off milk by 7-8w old
3 phases of calf development
- pre-ruminant phase (birth –> 3-4 weeks)
- transition phase (3-4 weeks –> weaning)
- ruminant phase (weaning –> 225lbs+)
pre-ruminant phase
- no functional rumen
- can’t digest solid feed
- abomasum is main compartment
- diet: milk, calf starter, water
how much milk/milk replacer to feed to preweaned calves
- summer: 2-3 quarts BID
- winter: 3-4 quarts BID
feeding starter grain/water to preweaned calves
- free choice starter grain after 3d old
- free choice water after 3d old
abomasal digestion in preweaned calves
- milk clots
- chymosin (rennin) acts on casein
- pepsin, HCl digest milk clot
intestinal digestion in preweaned calves
- sugars poorly digested (except lactose)
- starches/non-lactose disaccharides not digested until 3-4w old
- pancreatic enzymes increase gradually
transitional phase
- diet: milk, grain, water
- begin developing functional rumen (takes a minimum of 3 weeks)
- grain promotes production of butyric/propionic acid
what does feeding forage in transitional phase promote
acetic acid promotion –> doesn’t help with rumen development
post-weaning diet
- 1-2 weeks: grain, water
- 3+ weeks: grain, water, forages
fat sources
- lard (best, most economical)
- tallow
- vegetable (most expensive)
pros of feeding pasteurized non-saleable milk
- reduce pathogen transmission
- improve rate of gain
- improved calf health
- improved economic efficiency
- utilization of non-saleable product
cons of feeding pasteurized non-saleable milk
need more intensive management and monitoring (and a pasteurizer)
calf thermoneutral zone
10-20C, 50-70F
strategies to improve energy status in cold weather
- 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)
what starter qualities do calves prefer
- textured
- avoid fines, dust
- fresh
- palatable
importance of free choice water
- promotes rumen development (microbes, greater feed intake)
- essential to maintain hydration status (heat stress, illness)
water guidelines
- 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
weaning guidelines
- reduce stress by spreading out changes
- before weaning, should be eating starter for 3+ weeks at least 2lbs/day
- moving to groups
