Breeding Beef Cow

Question 1

Feeding breeding cattle is dynamic:

Answer 1

calving in early year (~march)
weaning end of year (~november)

Question 2

Nutrient Use Is Hierarchical

Answer 2

1) basal metabolism 🡢 greatest
2) immunity
3) lactation
4) growth
5) repro

Question 3

Energy use is hierarchical:

Answer 3

1) metabolism
2) grazing + other activities
3) growth
4) supporting basic energy reserves
5) maintaining + existing pregnancy
6) milk production
7) adding to energy reserves
8) estrus cycle + conception
9) storing excess energy

Question 4

Water is vital part of diet:

Answer 4

• non-lactating 🡢 3:1 H20:DM
• lactating 🡢 add gallon H20/gallon milk
• consider env. temp

Question 5

Cows like food, but not necessarily nutrients:

Answer 5

Intake:
- cows eat what they like not what they need
- cows balance DM intake, not nutrients
- cows have salt appetite
- appetite for minerals + vitamins hit/miss 🡢 use supplement mixes

Determinants of forage intake:
- feed types
- feed quality
- feed quantity
- protein content

Question 6

Metabolisc needs are production life cycle dependent:

Answer 6

Biological cycle 🡢 nutritional cycle (3 mo. intervals)
1) post calving 🡢 lactation + repro recovery
2) pregnant + lactating 🡢 maintenance + lactation
3) mid-gestation 🡢 calf-weaned + end of lactation
4) pre-calving 🡢 fetal growth

clinical manifestation of dietary deficit determined by stage at which occurs

Question 7

Cow’s nutrient requirement 🡩 by ___
with calving

Answer 7

30-40%

Question 8

metabolic starting point is important determinant of dietary needs:

Answer 8

Low BCS:
- BC
- fetus
- uterus, placenta, fluids

Heifer:
- growth
- fetus
- uterus, placenta, fluids

Good BCS (3.0-3-5)
- fetus
- uterus placenta, fluids
🡢 150-180 lbs

Question 9

clinical manifestation of dietary deficit determined by stage at which occurs

Answer 9

Biological cycle 🡢 nutritional cycle (3 mo. intervals)
1) post calving 🡢 lower milk. lower calf growth, poor fertility
2) pregnant + lactating 🡢 fetal viability
3) mid-gestation 🡢 fetal programming
4) pre-calving 🡢 calf weight, survival, colostrum, milk production, transition

clinical manifestation of dietary deficit determined by stage at which occurs

Question 10

env. temp has a major impact on nutritional reqs

Answer 10

🡩 winter ration En 1% for each degree below LCT

Question 11

Useful to divide herd into diff. def groups

Answer 11

Mature, good BCS
- average quality hay
- supplement with grain + minerals
- fortified salt + mins

Pregnant replacement heifers:
- good quality hay
- supplement with grain for growth
- not good at competing with mature cows

Thin + old cows:
- good quality hay
- supplement with grain + minerals
- need extra En for winter, often poor teeth

protein needs higher in growing heifers

Question 12

BCS

Answer 12

can be used as metric for dietary effectiveness, nutritional health + performance potential

higher BCS
- higher % of cows cycling
- higher % of pregnant cows
- higher # of calves with high serrum IgG
- better outcomes