Dairy cow management and production Flashcards
Largest portion of variable cost is
Feed cost. apprxox 60%
During what phase in terms of days is the PEAK profit making period of a lactating cow
6-8 weeks after calving
The energy gap of a lactating cow is most evident during which period in weeks
0-14
When is dry period
Early dry period-60-39 days prior to calving
Close- 21 days prior
When is transition period
21 days prior calving to 21 days after calving
As a general benchmark, at 100 days in milk, how many percent of a herd should be pregnant
50%
As a general benchmark, at 200 days in milk, how many percent of a herd should be pregnant
10% or less should be open
By 100 DIM, a cow should have produced _______% of her annual profit
50
What is the importance of monitoring
- To find out if something is broken
- To determine if management change is beneficial
- Bankers or investors
- Social gossip :3
Ideal BCS of calving cow
3.25-3.75
Ideal BCS of early lactation
2.5-3.25
Ideal BCS of dry off
3.25-3.75
Why is overconditioned cows a problem
Longer period of negative energy balance
Have higher incidence of fatty liver, metritis,
Lower total lactational milk yield
What is the key indicator of a cow’s reproductive potential
Days to first ovulation after calving
Why is thin cows a problem
Poor yield
Poor persistency of lactation
Poor fertility
Immunity suppresion
Biggest reason for culling dairy cow
Infertility (35%)
Mastitis (28%)
What is the proportion of dairy cows that are replaced yearly
1/3
6 basic cow activities for activity charting
Eating
Lying
Social
Drinking
Milking
Management
Why is cow activity important
Cows expressing normal behaviours are less stressed and express their full genetic potential in terms of milk production and reproduction
Rank optimum time spent per day of a cow doing these activities ( Lying, eating, drinking, social, milking,management)
Lying
Eating
Milking
Management/Social
Drinking
Let sleeping cows lie
Optimum time for a cow to lie down in a day
12hr
Optimum time for a cow to milk in a day
3hr
Freestall use index measures activity of all cows in a shed. How many percent of cows should be lying,standing,eating
90% should be lying
20% eating/drinking
5% standing
What method is used widely to breed dairy cow
AI
20% use natural breeding
Does the UK used sexed semen in breeding dairy cow
90% of AI used is sexed semen
How many open cows for a mature bull if you want to natural breed
35-50
Is natural breeding or AI a more effective way to breed
AI. Avg no. of pregnancy/bull/year is 41. 3-4 a month
What is minimum BSE of a scrotal circumferance
> 34cm
Bull heat detection is determined by which sense
70% sight. 30% smell
Autumn calving herds will calve at which periods?
Sept-Dec
Spring calving herds will calve at which periods?
Mid Feb
Seasonal calving involves breeding cows in a tight time frame. What is the duration of time frame
6-9 weeks
Do majority of dairy herds in UK use seasonal calving or all year round calving
All year round
What is daily energy requirement- maintenance for a cow
60-65MJ
What is energy requirement for 1 kg of milk
5.2MJ per Kg of Milk
What is daily energy requirement- liveweight gain
34MJ/kg
What is the energy requirement of a typical 600kg pregnant cow, gaining 0.5kg body weight a day and producing 20kg milk per day
200-210 MJ/day
What is daily energy requirement- pregnancy
23MJ
