Dairy 3 Flashcards
Feed costs
-single highest production cost on a dairy enterprise
*feed costs 30-35% total production costs
Components of dairy cow diet
- fibre sources: milk fat production
eg. alfalfa silage, pea silage, grass silage - Grains: gluconeogenesis
eg. Barley, corn
**feeds that are both grain and fibre= corn silage and barley silage
Alfalfa
Leaflet margin is less than 1/2 serrate
Pea
-higher milk fat, lower milk protein
- no loss of money feeding this
Barley
-requires less heat to grow
Corn silage
-requires more heat to grow and more water
Making a balanced ration
1.Nutritionist determines what feedstuff present on farm/ tell farmer what to plant
- Determine content of available feedstuffs by using Near Infrared (NIR) and wet chemistry
- Determine animal requirements
Dry matter intake
-critical for milk production
-feeds typically about 50% dry matter
Dry matter intake tax of cows
**amount of feed they need to stay alive; prior to milk production
Holstein: 6kg
Jerseys: 4.5kg
remaining intake x2= milk yield
Holstein production and feed
25kg DMI/day
-25-6=19kg for milk production
-38kg/day
Environmental factors of feed intake in cows
-air temperature
-plant toxins
-water intake and needs
What drives DMI
-bodyweight
-milk production
-BCS
-implants
What limits DMI?
-Ration NDF
-Ration NE
-forage mass/allowance
-Ration CP/TDN
Three diets concept
- formulated
- delivered
-hard to deliver exact amount of formulated feed - consumed
-some will sort through ration and eat what they like
Milk production based on feed
-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
Components of feeding systems
-ad lib feeding of forage
-concentrates fed separately (milk parlour, computer feeders, individual feeding station)
Disadvantages of feeding concentrates separately
-concentrates may be taken in during short period of time
-results in rumen pH fluctuations
-competition leading to grain overload
Mixed ration systems
-Total mixed ration system: all feed components mixed to form TMR
-Partial mixed ration: some grain fed in parlour
*composition of diet tightly regulated
Critical issues of mixing of mixed rations
-inadequate mixing: sorting and rumen pH fluctuations
-Overmixing: small particles leading to grain overload and or frothy bloat
Nutritional steps
1.Characterize low production
- Evaluate average days in milk
- Evaluate trends in herd size
- evaluate herd nutritional management
- Evaluate cows
- Evaluate cow environment
- Additional testing
Characterizing low production
-evaluate milk production by time and parity
-determine reasons for low production in heifers vs. cows
Reasons for low production in heifers
-overcrowding- dominant individuals (cows over heifers) will outcompete for food
-pen moves- can lead to competition
-small size at calving
-overconditioned at calving
Reasons for low production in cows
-underfeeding
-ketosis
-lameness
Evaluate average days in milk
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
Evaluating trends in herd size
-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
Health problems and herd size
-death loss
-reduced heard size
-reduced milk yield
Long term low production from herd size
-nutrition problems
-health problems
-increased days in milk
Short term low production from heard size
-expansions
-health problems
-nutrition problems
Evaluate herd nutritional management
-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
Evaluate the cows
-BCS
-cud chewing
-manure evaluation
-lameness
-sick cows
Evaluate cow environment
-freestalls
-resting surfaces
-flooring
-ventilation
Herd testing
-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
Recommendations
-Make less than 3 total recommendations- ideally 1
-ensure they are related to herds goals and are directly related to herd issues
