Dairy 3

Question 1

Feed costs

Answer 1

-single highest production cost on a dairy enterprise
*feed costs 30-35% total production costs

Question 2

Components of dairy cow diet

Answer 2

1. fibre sources: milk fat production
   eg. alfalfa silage, pea silage, grass silage
2. Grains: gluconeogenesis
   eg. Barley, corn

**feeds that are both grain and fibre= corn silage and barley silage

Question 3

Alfalfa

Answer 3

Leaflet margin is less than 1/2 serrate

Question 4

Pea

Answer 4

-higher milk fat, lower milk protein
- no loss of money feeding this

Question 5

Barley

Answer 5

-requires less heat to grow

Question 6

Corn silage

Answer 6

-requires more heat to grow and more water

Question 7

Making a balanced ration

Answer 7

1.Nutritionist determines what feedstuff present on farm/ tell farmer what to plant

2. Determine content of available feedstuffs by using Near Infrared (NIR) and wet chemistry
3. Determine animal requirements

Question 8

Dry matter intake

Answer 8

-critical for milk production
-feeds typically about 50% dry matter

Question 9

Dry matter intake tax of cows

Answer 9

**amount of feed they need to stay alive; prior to milk production

Holstein: 6kg

Jerseys: 4.5kg

remaining intake x2= milk yield

Question 10

Holstein production and feed

Answer 10

25DMI/day
-25-6=19kg for milk production
-38kg/day

Question 11

Environmental factors of feed intake in cows

Answer 11

-air temperature
-plant toxins
-water intake and needs

Question 12

What drives DMI

Answer 12

-bodyweight
-milk production
-BCS
-implants

Question 13

What limits DMI?

Answer 13

-Ration NDF
-Ration NE
-forage mass/allowance
-Ration CP/TDN

Question 14

Three diets concept

Answer 14

1. formulated
2. delivered
   -hard to deliver exact amount of formulated feed
3. consumed
   -some will sort through ration and eat what they like

Question 15

Milk production based on feed

Answer 15

-increased age at 1st calving decreases production

-increase stalls/cow, increases production

-pushing up feed= 3.8kg more milk

-Feed refusals= 1.6kg more milk; means that you fed them enough or have more available at all times so more milk

Question 16

Components of feeding systems

Answer 16

-ad lib feeding of forage

-concentrates fed separately (milk parlour, computer feeders, individual feeding station)

Question 17

Disadvantages of feeding concentrates separately

Answer 17

-concentrates may be taken in during short period of time
-results in rumen pH fluctuations
-competition leading to grain overload

Question 18

Mixed ration systems

Answer 18

-Total mixed ration system: all feed components mixed to form TMR

-Partial mixed ration: some grain fed in parlour

*composition of diet tightly regulated

Question 19

Critical issues of mixing of mixed rations

Answer 19

-inadequate mixing: sorting and rumen pH fluctuations

-Overmixing: small particles leading to grain overload and or frothy bloat

Question 20

Nutritional steps

Answer 20

1.Characterize low production

2. Evaluate average days in milk
3. Evaluate trends in herd size
4. evaluate herd nutritional management
5. Evaluate cows
6. Evaluate cow environment
7. Additional testing

Question 21

Characterizing low production

Answer 21

-evaluate milk production by time and parity

-determine reasons for low production in heifers vs. cows

Question 22

Reasons for low production in heifers

Answer 22

-overcrowding- dominant individuals (cows over heifers) will outcompete for food
-pen moves- can lead to competition
-small size at calving
-overconditioned at calving

Question 23

Reasons for low production in cows

Answer 23

-underfeeding
-ketosis
-lameness

Question 24

Evaluate average days in milk

Answer 24

Determine where in lactation the average cow is (typically=300-305 day lactation)
-indicates reproductive efficiency
-conceive later=longer lactation
-longer lactation=avg cow further in lactation
-increased days in milk= decreased milk

Question 25

Evaluating trends in herd size

Answer 25

-herd expansions can decrease milk yield for up ot one year
>construction
>disease
>overcrowding
>reduced milking
>reduced social interactions/hierarchy because they only remember about 80 other cows

Question 26

Health problems and herd size

Answer 26

-death loss
-reduced heard size
-reduced milk yield

Question 27

Long term low production from herd size

Answer 27

-nutrition problems
-health problems
-increased days in milk

Question 28

Short term low production from heard size

Answer 28

-expansions
-health problems
-nutrition problems

Question 29

Evaluate herd nutritional management

Answer 29

-determine what the cows are eating (takes time, need samples)

-evaluate feed ingredients (see feeds and system, analyze dry matter, forage and grain particles, ensiled feed pH)

-determine amount fed (interview feeder, watch them feed cows, determine amount offered and refused, double check scales)

-reconstruct diet (from scratch)

-evaluate TMR

Question 30

Evaluate the cows

Answer 30

-BCS
-cud chewing
-manure evaluation
-lameness
-sick cows

Question 31

Evaluate cow environment

Answer 31

-freestalls
-resting surfaces
-flooring
-ventilation

Question 32

Herd testing

Answer 32

-testing alone will never solve a problem; need to corroborate with other findings

-Test rumen pH by rumenocentesis/stomach tube

-Blood tests for ketosis (energy balance)

-Urinary pH= hypocalcemia

-Milk Urea Nitrogen (MUN)= protein utilization

Question 33

Recommendations

Answer 33

-Make less than 3 total recommendations- ideally 1

-ensure they are related to herds goals and are directly related to herd issues