6 Milking Management 2 Flashcards
Objectives of data management
- conduct routine work more efficiently
- identify less productive animals (for culling)
- improve profitability of dairy operations
Abbreviations M, F and P in data management
M = milk
F = fat
P = protein
Factors affecting milk yield
- management
- genetic potential
- stage of lactation
- parity (age)
Percent of milk yield expected in 1st, 2nd and 3+ lactations
1 = 70-75%
2 = 90-95%
3+ = 100%
Still growing in first and second
Lactation length of dairy cow, dry period length
305 day lactation
60 day dry period
What is BCA
Breed Class Average
Index for milk, fat and protein yield across Canada
Allows fair comparison of cows that differ in breeds, ages and calving months
Two ways of comparing production among cows
- 305 day production (actual or projected)
- BCA
Slide 13
DRTC Herd Management Report
Know how to find info
What factors decrease the proportion of 3+ lactation animals in a herd
- more involuntary culls (mastitis, disease, etc)
- low reproductive efficiency
What is RHA
Rolling herd average
Average of terminated records in the herd for the last 365 days
Average rolls forward each test date (e.g. every month on same day, new cow records added, records more than 365 days old are deleted)
When does a record enter the RHA
At day 305 or at termination date (dry-off, cull, died) if less than 305 days
Why is RHA usually lower than current herd average?
If cows had mastitis or were culled, they are still included in RHA but not current average (excludes failure)
Milk yield is standardized to… Why?
- 150 days in milk
- second lactation
- fat content 4.0%
- protein content 3.3%
Allows fair comparison of milk production of a herd from month to month
Majority of lactation problems occur when?
At very early lactation
Feeding more grain in a dairy diet does what?
Increases milk yield and protein content
Decreases milk fat content
