Transition

Question 1

the lactation curve

Answer 1

• rapid increase in milk production, DMI lags behind
• cow mobilizes reserves, lose BW
• body weight will drop but not milk
• mobilize 80% adipose tissues
• 20% skeletal muscle going for milk production

Question 2

what is the transition period

Answer 2

• last 3 weeks of gestation + first three weeks lactation
• time of most infectious disease and metabolic disorders
  milk fever
  ketosis
  retained fetal membrane
  metritis
  displaced abomasum
  mastitis
  domino effect - once you get 1 you get them all

Question 3

mastitis

Answer 3

• ## mammary gland infection #1

Question 4

milk fever

Answer 4

• blood calcium drops, recumbant/cant stand up, low milk production

Question 5

ketosis

Answer 5

milk drops by 535 kg/lactation

Question 6

retained fetal membranes

Answer 6

milk drops by 8.2 kg/d

Question 7

metritis

Answer 7

uterus infection

Question 8

displaced abomasum

Answer 8

• get gas filled = needs surgery
• drop in milk by 900 kg/lactation

Question 9

metabolic diseases are costly

Answer 9

• loss of milk production, discarded milk (loss of income = discard infectious milk, energy is going to immune response)
• veterinary and drug expenses
• early culling, dead animals (25% of cows leave herd within 60 DIM)
• cst of replacements (2500 to replace a heifer)
• impaored reproduction ( after gaining disease - cant have offspring)

Question 10

breaking down the transition period

Answer 10

• pre-partum phase
• decline in DMI
• increase in energy demand ( fetal growth, mammary developmen)
• negative energy balance is perfectly normal

Question 11

why could transition cows be at risk

Answer 11

• going from dry - to lactating diet, lower energy to high fermentability and high starch
  microbial changes
  pH changes
  epithelial/papillea will change in order to absorb SCFA
• increasing the risk of ruminal acidosis

Question 12

removal of acid from the rumen

Answer 12

52.0% absorbtion
28% salivary bicarbonate
15.5% passage
3.6% other

Question 13

ration energy for preparing the rumen and microbes

Answer 13

when approaching calving there is low energy ration provided
theres a lag period for cells to turn over and adopt before calving after a high energy ration is introduced

Question 14

off feed events decrease SCFA absorbtion

Answer 14

low DW reduces VFA creation
5 days of low feed intake (LFI; 25% of voluntary intake ) reduced absorptive surface area in the rumen by more than 50%

Question 15

what disease increases risk during off feed events? why?

Answer 15

ruminal acidosis
- when DM is provided in higher amounts, ruminal acidosis can be present

Question 16

when is the prevalense of SARA in early lactation for holstein heifers the most in days

Answer 16

• 17-19 days
  37-39 days
  1-5 days
  59-60 days
  -5-0 days
  SARA may pean in early lactation

Question 17

close up phase sets up lactation “old theory”

Answer 17

low - high , lets feed something in the middle
- steam up diets
- increase nutrient density to compensate for low DMI

Question 18

what are issues with the close-up phase old theory

Answer 18

• increases reduction in DMI
• does not reduce risk for ruminal acidosis
• does not help facilitate the transition rfrom a non-lactating pregnant state to a lactating non-pregnant state

Question 19

why doesnt steaming up work

Answer 19

• fed pre partum diets that were different in NE
• no difference in milk or component yield
• no reduction in risk for ruminal acidosis - infact increased risk for severe RA
• no effect to reduce NEFA or BHBA

Question 20

“too much” risk factors in the dry period

Answer 20

• body condition
• weight loss in dry pen
• time in dry pen
• energy
• too many lactations
• twins/triplets
• grain
• overcrowding
• excess soluble protein
• potassium
• molds and mycotoxins

Question 21

“too little” risk factos in the dry period

Answer 21

• body condition
• weight gain in dry pen
• time in dry pen
• selenium
• energy
• dry matter intake
• fire
• protein
• magnesium
• cow comfort

Question 22

the goldilocks approach

Answer 22

• higher NE diet in dry period reduce post partum DMI, greater BCS loss - what not to do
• lower decrease in DM pre-partum, greater DMI post-partum decreased DA by 85% ketosis by 75% milk fever by 76%
• fill them with rumen fill

Question 23

common problems for close u[ and lactation

Answer 23

sorting - reduce chop length or add a binder
- overcrowding