Dairy 2 Flashcards
Life cycle of a dairy cow
- Lactating cows
- Dry cows
- Calving
- Calves- replacement heifers and bulls
- Bulls mostly go into beef, some used for breeding
Calving age
22-24mths old
Breeding age
~60 days in milk (means since calving)
Lactation timing
~60 days before calving (300-360 DIM)
Dry period
~60 days
Lactation and body reserves
-body reserves drop off during early lactation
-body reserves regained at late lactation
BCS
-determines fat, protein reserve
-helps with deciding about nutrition, reproduction readiness, post-partum disease, milk production
**if BCS<2, need to do something
Housing during lactation
- Free stalls
- Tie stalls
- Pasture
- Bedding packs
Free stalls
-most common system
-N. America and Europe
-allows animals to move around freely; feces hopefully come out back end
Tie-stalls/ Stanchian Barns
-welfare concerns, becoming unpopular with producers because animals are tied up all the time
-sometimes have cow trainers (electric shock) to make cows back up and pass feces outside stall
Pasture housing
-New Zealand
-warmer weather
-low overhead costs; but lower milk production
Bedding packs
-low initial cost, high maintenance
-cleaning is an issue because there is no regulation about where their manure is
Milk machine musts
- minimize trauma to mammary tissue
- minimize pathogen spread between animals
**vacuum with pulsation to prevent damage
Milking systems
- Milk in parlour
- Milk in stalls in tie stalls. Cow does not move
Parlour types
- Static facilities (eg. herringbone parlours)
- Rotary/carousal facilities
- Robotic milkers
Number of dairy milkings
-Cows will choose to be milked 3x a day. Will see a 10-15% increase in milk production
Milk storage
1.Bulk tank: <4C
2.Pickup every other day in SK
-each pickup tested: antimicrobials, water, other contaminants
**there can be more frequent milkings on larger facilities… milk directly onto truck
What is occurring during dry period?
-prepare for parturition
-cell turnover in mammary gland
-colostrum production
Length of dry period
Typically 60 days
Shorter dry periods research
-due to high milk production
-increased milk production in lactation before dry period
-no demonstrated adverse effects if more than 40 days
Issues with drying cows off
-stopping milking
-cows may still have high production
Issues with abruptly drying cows off
-stop milking immediately
-results in discomfort issues but has less risk of mastitis
Issues with gradually drying cows off
-less discomfort
-increased risk of mastitis because gives more time for the bacteria to adhere to udder
Feed and water during drying cows off
-Feed: do not remove feed and do not make extreme changes
*used to be done to dry off
-Water: should always be available. Do not restrict water intake
*used to be done to dry off
Herd composition
-youngest heifers on farm should have best genetics
-culling rate should be around 30%; heifer mortality should be around 8%
*low cull rate=more older cows=more efficient herd
High cow culling rate + high heifer mortality= insufficient supply
Fate of bulls
-Rarely for breeding
*too dangerous
-more commonly used for beef
*cross breeding=better beef quality
Common cross-breeding practice
-best heifers and cows reproduced with sexed Holstein semen= holstein heifer born
-lower genetic individuals bred with beef semen so they do better in feedlots
eg. Angus, Speckle Park, Shorthorn, Wagyu
Economics of dairy farming
-gross income: $86.41/hl milk sold
-Production costs: $83.24/hl milk sold
-Avg cow: 97hl/year
-Avg farm: $52,000/yr for 170 cows
Top1/3 of farms: $1409 ($240,000)
Bottom 1/3 of farms: $-677 ($-115,100)
Typical dairy investments
-Building and equipment: $15,243/cow
-Livestock: $3437/cow
-Land and supples: $1020/cow
TOTAL: $19,700/cow
Debt: 32%
Equity: 68%
Least cost vs. max margin
Cutting costs often decrease efficiency
-efficiency to maximize margin (return in profit over costs)
Dairy ownership
Most commonly Family corporations= larger herds
-Sole proprietorship= smaller herds
Modern dairy data collection
-tracts production, cow parameters, precision farming systems
Lactanet
dairy recording system in Canada
Rules for record keeping
-useful
-readily converted information
-simple
-avoid duplication
-take action on records
