Large animal maternal nutrition

Question 1

Mare gestation, lactation and weaning lengths

Answer 1

Gestation = 11 months 11 days
-Early = first 4 months
-Late = last 4 months

Lactation
-Early = first 2 months
-Late = months 3+

Weaning @ 4-6 months

Maintenance

Question 2

Beef cow gestation, lactation, weaning length

Answer 2

Gestation
-Late = last 2 months

Lactation
-Early = first 80 days

Weaning = 6-10 months
calf 400-600lb

Question 3

Dairy cow gestation, lactation, weaning length

Answer 3

Gestation = 275-280 days
-Late (close-up) = last 2-3 weeks

transition dairy cow

Lactation
-Peak @ 45-90 days, w/in 1st 150 days in milk

Weaning w/in 24hr

Question 4

Nutritional Goals for the Dam

Answer 4

Maximize production (offspring, milk)
Maintain rumen and hindgut health

Reduce risk of …
Negative energy balance
Ketosis / Pregnancy toxemia
Hepatic lipidosis
Increased risk of infection
Hypocalcemia

Question 5

Ideal BCS for mare prior to pregnancy

Answer 5

5/9-6/9

IMPROVE BEFORE BREEDING

Question 6

Ideal Dairy Cow BCS prior to pregnancy

Answer 6

Target 3.0/5-3.5/5

< 3 associated with lower milk yield & greater risk of milk fever

> 3.5-4 associated with lower DM intake during lactation, lower milk yield, higher risk of ketosis

Adjust in late lactation

Question 7

Dairy Cow BCS loss >1 during lactation is associated with…

Answer 7

Longer time to first ovulation
Longer time to first service
Lower conception rate at first service

Question 8

Ideal Beef Cow BCS prior to pregnancy

Answer 8

Target 5/9-6/9

1/9-4/9 associated with reduced pregnancy rates, longer postpartum intervals & conception later in breeding season and thus calves born later

8/9-9/9 fat

Question 9

Water requirements in the mare and cow during lactation

Answer 9

> 120ml/kg BW
2-3x higher during lactation than maintenance (~60ml/kg BW)

Free choice potable & palatable
Parallels energy requirement

Question 10

Protein in addition to maintenance requirements (e.g. for muscle, hormones, enzymes, etc.), needed for feti and associated….

Answer 10

Tissue development

Question 11

Protein source in the mare and cow

Answer 11

Diet (mare)
Diet AND microbial (cow)

Crude protein (nitrogen)
Metabolizable protein represents absorbed AA
Net protein represents retained protein

Question 12

Protein deficiency in pregnancy adverse effects

Answer 12

Reduced weight gain in the dam
Reduced birth weights +/- growth rate post-weaning
Reduced immunity

Question 13

Fat requirements in cows and mares

Answer 13

Requirement UNCLEAR

Energy density (very)

Rumen microbial hydrolysis, hydrogenation & conjugation of PUFAs
-Odd chain fatty acid
-Conjugated linoleic acid (CLA)

Excess ->
Diarrhea
Reduced microbial fermentation

Vitamin E protects PUFAs

Question 14

Hypocalcemia in the Dairy Cow

Answer 14

CS – tetany (milk fever)

Risk factors:
Lactation (2 months post calving)
Anorexia / hyporexia
Inappropriate diet i.e. high Ca diets prior to calving

Treatment: parenteral calcium

Prevent with proper transition diet

Question 15

Calcium is needed in cows for…

Answer 15

Milk production
Bone/endochondral ossification

Question 16

Copper bioavailability is reduced with excess…

Answer 16

dietary phosphorus, zinc and/or molybdenum

Question 17

A deficiency in copper is associated with offspring __________.

Answer 17

physitis

Question 18

Carbohydrate sources in mare/cow diet

Answer 18

Physical fiber
VFA production
Euglycemia (horse)

Question 19

Cow/mare ration should consist of…

Answer 19

Forage

+/- concentrate
Commonly fed to mares
Depends on forage quality & availability

Vitamin/mineral
If not feeding enough concentrate to meet needs

Question 20

Dairy Cow Ration is typically…

Answer 20

Total mixed ration (TMR)

Higher milk fat & milk production with TMR vs. pasture + concentrate

Question 21

Anticipated dry matter (DM) intake in the mare

Answer 21

Varies deepening on stage

Early gestation 2% (varies!)
Late gestation 2% BW
Lactation 2.5% BW

Question 22

Anticipated dry matter (DM) intake
in the dairy cow

Answer 22

Varies depending on the stage

Limited in late gestation
Week 1-6 of lactation 2.5 – 3.5% BW
Week 8-16 of lactation 3.5 – 4.0% BW
Week 16+ of lactation 2.5 – 3.0% BW

Question 23

Neutral detergent fiber (NDF) is negatively correlated with…

Answer 23

Forage quality
As NDF increases (more mature plant), quality decreases

Generally, alfalfa is more energy and protein dense than grass

Question 24

The % of NDF should be lower during (early or late gesation)

Answer 24

Late gestation (NDF adds bulk and not a lot of space in stomach during late pregnancy)

Question 25

Endophyte Infected fescue may lead to…

Answer 25

Abortion, placentitis, agalactia
Summer slump, fescue foot

Question 26

Concentrates should not be added to the diet if…

Answer 26

If BCS and muscle condition is ideal with forage, than no need for concentrates (i.e. forage alone appears to be meeting energy & protein needs

Question 27

Commercial Concentrate for Cows

Answer 27

Labeled for “cow & calf”

Balancing …
nutritional needs
cost of feeds

Question 28

Generally concentrates should be discontinues __-__ weeks prior to weaning

Answer 28

1-2

(Individually, consider BCS & rebreeding status)

Question 29

Monitoring diet during/after gestation

Answer 29

Repro records
Production
BCS
Dry matter (DM) intake
Watch the herd eat
Blood glucose
BUN (low with low DMI intake)
Potassium (low with low DMI intake)
Beta hydroxyl butyrate (BHB; elevated with low DMI; 2018 VanSaun)