What are the 3 largest expenses of the dairy business?
feeding lactating cows (#1), raising replacement heifers, labor
What determines day on feed? (4)
age at calving, which is determined by nutritional management, ADG/development, conception
What are the main characteristics of transition cow management? How is this different from traditional management?
- focused on management of pre- and post-partum requirements (energy, protein, vit/minerals) to prevent decreased dry matter intake and metabolic disease [vs. focused on treatment of dz]
- manage groups of cows separately based on reproductive status [vs. individual problem cows]
- Monitoring processes [vs. monitoring results and responses]
When is the transition period, and what are the goals of transition cow management?
3 weeks pre-partum to 3 weeks post-partum: resting, avoid drop in dry matter intake and negative energy balance, water quality is of importance (Na, K, S, Cl) [prevent milk fever and ketosis]
What should be done at dry off? (4)
- dry treatment (mastitis prevention)
- hoof trimming (lameness prevention)
- vaccination (mastitis prevention)
- Pre-partum diets (metabolic disorder prevention)
What should be done to manage cows in the close-up group? (2)
- DCAD diet (prevent milk fever)
- Vaccination (prevent mastitis and neonatal diseases)
When are cows dried off?
~230 days gestation (7 months)
When should cows be moved to the close-up group?
~255 days gestation
What should be done to manage cows at calving? (3)
- moved to maternity pen
- minimize calving-related losses
- trained personnel for neonatal care
What is important to manage is the early post-partum group? (3)
- diagnosis/txt of dz (metritis, mastitis, ketosis, milk fever)
- diet to support lactation
- maintain dry matter intake (avoid ketosis)
What are important management factors for the lactation group? (3)
- diet to support high milk yield
- recover lost BCS
- initiate reproductive program
What are the basic physiologic demands in order to avoid transition cow disease? (4)
- resting time (b/w 12.5-14hrs/day)
- dry matter intake and adaptation of the rumen to lactation diets (avoid ketosis)
- maintenance of normocalcemia (avoid milk fever)
- maintenance of a strong immune system (avoid infectious disease, mastitis)
What is the highest prevalence disease associated with calving?
When is dry matter intake at its lowest during a cow's life?
just before and at calving [this is bad because this is when their energy needs are ramping up for lactation--> negative energy balance--> ketosis]
How is serum Ca2+ affected through life with regards to calving?
as an animal gets older, it is harder to mobilize Ca2+ stores to compensate for the extreme loss of Ca2+ in colostrum just after calving--> prevalence of milk fever goes up in older cows
When the resting time budget of lactating dairy cows b/w 1-30 days in milk (transition period) is altered, ___________ is the direct result.
low dry matter intake
What potential problems could cause a disturbance in the time budget for resting fresh cows? (7)
high stocking density, not enough bunk space, distance to pasture too high, poor feed bunk management, more frequent milking, commingling primiparous and multiparous cows, PERSONNEL
If pre-fresh and early lactation cows have a negative energy balance, the _____________ of these animals is compromised; it can also lead to...
reproductive capacity; metabolic disorders, such as ketosis and fatty liver.
Dairies should be built around _________.
cow comfort (increased resting--> increased milk and DMI and decreased disease)
What is the best predictor of NEFA and BHBA status after calving?
Energy and calcium balance affect ___________ function.
Factors that reduce reproductive cyclicity at 21 days in milk. (6)
BW loss >28kg, metabolic disease, metritis, dry period length >76 days, calved in winter, pluriparity
For a 100 cow herd with a cull rate of >30%, ...
monetary losses may offset milk genetic progress [you need to keep some older multiparous cows around!].
What are risk factors for decreased lifetime performance of replacements? (4)
increased calving difficulty, higher weaning age, days ill, lower DMI at weaning
Milk yield _________ in the 2nd and 3rd lactation; mature cows are at _________ for transition diseases.
increases; higher risk
Culling offers an opportunity to __________, but culling rate ________ may offset the milk genetic progress.
replace unproductive animals; >30%
Genomic selection offers an opportunity to select superior replacement heifers, but _________ determines the lifetime performance regardless of genetic merit.
management early in life