MIDTERM II

Flashcards with the material for midterm 2

Pros to baleage

Pros to baleage

• forages harvested at higher moisture content (decreases curing time)

• Good for spring cutting of annual ryegrass/crimson clover or tall fescue

• Minimal spoilage and weathering of \n the baleage as long as the plastic is \n not torn \n – Baleage often has higher palatability \n than dry hay

Cons to baleage

• Stored forage remains an expensive commodity. Increased equipment needs and cost for baleage

• Wrapping bales will slow the baling process and/or increase labor needs

• Wrapping plastic must be handled and discarded appropriately

• Poor quality forage that is ensiled as baleage is still poor quality forage

Crop types for silage

• Hay crop silages

  • Forage grasses and or legumes, winter grains

• Grain crop silages

  • Corn or grain sorghum

  • corn is good bc it ensiles really well and you get a lot (harvest at 65% moisture)

Types of hay crop silage

• Grasses, alfalfa, wheat, barley, rye, ryegrass

• Chopped from standing crop, taken to silo

• Forage too wet ~80 % water

  • Favor Clostridia (loss of DM)

    • Butyric acid formation (smells bad!)

  • Slow to ensile, longer to reach safe pH

  • Water drains out (seepage)

    • Removes soluble nutrients

• Wilted hay crop silage ~ 65-55% moisture

Corn makes high quality silage

• Under anaerobic conditions carbohydrates make organic acids instead of respiring to CO2

• Corn has lots of carbohydrates

  • Acidifies quickly

  • Wider moisture harvest window

  • Relatively stable silage

• Standing corn is harvested when it has field-dried down to 65% moisture

Theoretical length of cut (Corn silage)

Chopper not fitted with an on-board processor

• Use chopping or knives to break up cob and kernel

• 3/8 inch theoretical length of cut

Chopper with kernel processor

• 3/4 inch of theoretical length of cut

• Processor setting is anywhere from 1 to 2 mm

A properly adjusted kernel processor:

• Damages more than 90% of the \n kernels

• Pulverize cob pieces

  • Minimizes waste in the feed bunk

• Allows for longer length of cut

  • Longer fiber

  • Less power consumption

Feeding rate

• The recommended minimum removal rate is 12” per day

• At no time should more than three days worth of silage be exposed

• Always close the bag off after each feeding

  • Open bags cause billowing plastic that pumps air over the silage

• Removal method

  • With a bucket scrape the silage from the top

  • Allow it to fall to the floor

• Avoid methods that result in dislodging the face

  • Creating gouges, cracks, and potholes

  • Air penetrates deep into the silage

Heifer

female bovine that has not calved

Cow

used after calving, calve at 24 months of age roughly once per year, milks for about 10 months, dry for roughly 2 months, calving induces lactation

lactation

time between calving (think lactation curve)

1st lactation cow

has had one calf, in her first lactation

first breeding

15 months of age

first calf

24 months

gestation length

9 months, 283 days

breed again

27 months of age

second calving

36 months

transition cows

+/- three weeks of calving (prior to and after)

Factors involved in the lactation curves

• milk produced

• amount of feed eaten

• body weight

• cows have a higher DM intake during the start of lactation

• cows also use up a lot of their stored body fat at the start of lactation (to make up for a deficit of energy collected from the feed)

Feed efficiency (MIlk/DMI)

• on average it is 1.5

• higher at the start of lactation (where they make the most money bc the cow is using the fat reserves for energy)

• low (losing money) at the end of lactation where less milk is taken up

Stall density

• lactating cows 100-120%

• transition cows 80-100% (no more than 100% bc fights)

Feed bunk information in a stall

• feed available at least 26 hrs a day

  • want it there when they come back from milking

• feeding time: day to day

• push 4-6 times a day

• lactating cows need 24 in of bunk space

• close-up and fresh cows need 30 in of bunk space

Feeding frequency

• 1x is ok in fall/winter/spring

• 2-3x in summer/humid months

Feedbunk scoring

How much feed should we offer?

• average of 5% of refusals

  • 3-5% fresh cows

  • 1-5% early lactation/high producing

  • 0-5% late lactation

• what do you do with the refusals?

  • discard low quality

  • if feed is still quality … feed to small groups, steers, etc

Reasons for variable feed intake

• TMR dry matter (might be an incorrect dry matter amount)

• Number of animals in the pen (if there aren’t as many as you thought you were feeding, there will be more food left over)

• Forage quality (lower qual = feed left behind)

• Animal (Heat Stress) and TMR temperature

  • feed at night

  • feed several times a day

  • use chemical preservatives

Formulating dairy cow diets

• Goals:

  • to meet the cow’s nutritional needs while maintaining health

  • to optimize milk production, milk fat, and milk protein

  • accomplished economically

• all rations should contain at least 1 feed from each category:

  • forage

  • grains

  • protein supplements

  • minerals

  • salt

Excess fiber in the diet can result in:

• low milk production

• DMI lower than expected

• high milk fat percent

• early lactation cows fed too high forage and low energy of rations may be more prone to ketosis and have rapid body weight loss

A deficiency of fiber can result in:

• acidosis, cows going off feed and fluctuating drying matter intake

• low milk fat percentage

• cows not chewing their cud

Fats, minerals, and vitamins

• total fat should not go above 7% of the diet DM

  • no more than 2% added fat should be from: animal, vegetable, or rumen inert

• salt: cows need 3-4oz of salt per day

  • one ounce plus 1 ounce for every 25lbs of milk

• calcium: 0.75-1% of DM diet

• phosphorus: 0.35 to 0.40% of DM diet

• need Vitamin A, D, and E

Water

• 60 to 80% from drinking water, 25-35% from water/moisture in field

• Cows should consume 3-5lbs of water per lbs of DMI

  • 50 lbs of DMI at 4 lbs of water = 200 lbs of water per day or 25 gallons per day (divide lbs by 8)

• 2-4 in of perimeter space per cow

  • water depth at min of 2 in

• at least 2 watering locations per pen to prevent dominant cows from guarding waterer

• water tank should be located within 50 feet of the feed bunk or at every crossover in a freestall barn

• water should be immediately accessible after returning from milking

Signs of CHO unbalance

• lack of persistency in lactation curve

• laminitis

• liquid manure

• inc incidence of ketosis, displace abomasum and repro problems

• reduction in DMI and milk fat content (protein: fat inversion)

  • protein level in milk is higher than the fat

Nitrates Toxicity

• Nitrates are the primary form of available N in soil

  • plants take more up in droughts

• Taken up by plant roots

  • From organic and inorganic sources

• Metabolized into plant proteins

• Toxic when animals consume large amounts of nitrate when animals consume large amounts of nitrate

  • Safe when < than 0.44% of DM

  • From 0.44 to 1.5% dilute with feed low in nitrates from 0.44 to 1.5% dilute with feed low in nitrates

  • 1.5% do not feed

• nitrates in high lvls = toxic for ruminants

Why does this matter? \n Nitrate toxicity in ruminants

Nitrate Accumulation

• certain plants have a higher potential for accumulation

• Environmental conditions that prevent nitrate metabolism

  • Drought and frost conditions

  • Decreased light (cloudy weather, early in the day)

  • Decreased temperature

Nitrate Accumulating Crop Plants

Tall fescue

• drought tolerant

• tolerates moderately poor soil drainage

• adapted to piedmont, mountains of SC

• tolerates wide ranges of soil pH

• reproductive phase in April-early June

  • vegetative the rest of the year

Unique prob. with tall fescue

• desirable attributes are due to endophytic fungus

  • inside the plant

• costs the beef industry from $600 million to 1 billion annually

Tall fescue endophyte

• no visible plant symptoms of fungal infectio

• beneficial effect on grass

  • reduce grazing in late spring

    • forage accumulation > summer survival

  • inc leaf rolling

  • alkaloids with anti-insect properties

  • inc germination rate and tiller growth

  • fescue becomes more persistent

    • selection/adaptation advantage

• fungus produces mycotoxins (ergot alkaloid ergovaline) that cause health problems for grazers

Symptoms of tall fescue toxicosis

• reduced intake

  • reduced weight gain and milk prod

• vasoconstriction at extremities

  • fescue foot → mainly during cold weather

• inc body core temp

  • exacerbated during hot weather (summer slump)

  • animals spend more time cooling than grazing

• inc resp

• lowered hr

• altered fat metabolism

  • fat necrosis intestinal tract

• affected cattle typically have “rough hair coats”

• conception rates <50% in beef cattle

• horse: prolonged gestation length, late gestation abortion, dystocia, thickened placenta, agalactia

Ketosis

• conditions associated with intense fat mobilization un cattle

• elevated conc. of ketone bodies in all bodily fluids

  • acetone, acetoacetate, beta-hydroxybutyrate

• cows with ketosis can be identified via routine testing using appropriate cow side blood, milk ($$$), or urine tests

• the most efficacious treatment for ketosis is oral drenching of propylene glycol

Fatty liver

• results from a state of negative energy balance

  • imp metabolic diseases of post parturient dairy cows

  • fatty liver at calving is commonly associated with:

    • ketosis

    • feed intake depression and dec milk prod

• excessive triglyceride accumulation in liver cells results in disturbed liver function

• avoiding over conditioning cattle

  • dry period, avg BCS of 3-3.5

  • over conditioned cattle (BCS > 4) should not be feed restricted because this will promote fat mobilization

Body Condition Score (BCS)

• less than 3: angle between hooks and pins is a V

• greater than 3: angle is U shaped

• honestly from there look over the guide from lab

  • ie if you see ribs it’s in the 2s

  • if its round probably in the 4s

Milk Fever

• aka parturient paresis

• acute to peracute, afebrile, flaccid paralysis of mature dairy cows that:

  • occurs most commonly at or soon after parturition

• can contribute to dystocia, uterine prolapse, retained fetal membranes, metritis, abomasal displacement, and mastitis

• restore normal serum calcium levels as soon as possible

  • IV injection of a calcium gluconate salt

• prevention:

  • dec blood pH by dietary cation-anion difference

    • reduce K in the diet or add anionic salts

Left Displaced abomasum (DA) (90% of DA)

• Abomasum occasionally may be displaced to the left of the rumen and upwards when its muscular wall loses tone, and the stomach becomes filled with gas

• Low forage diets and sudden changes in grain feeding levels may result in DA

• Clinical signs include anorexia and decreased milk production

  • Treatment cost ($100300 per case)

  • Treated cows produce ~800 lbs. less the next month

• Permanent correction is best achieved by surgically entering the abdomensurgically entering the abdomen

Sub-acute ruminal acidosis (SARA)

• periods of moderately depressed ruminal pH ranging from 5.5-5.8

  • decreased milk prod and efficiency of milk prod

  • premature culling, in death loss

• prevalence of SARA in dairy herds estimated at 19-29% in lactating cows

• hard to detect, can occur for many reasons (nutrition big reason tho)

Regulation of rumen pH

Typical pattern of rumen pH variation during the day

Specific signs associated with \n SARA

Digital dermatitis

• leading cause of lameness

  • ~$150-200 per case in the form of treatment costs and lost production

• needs a bacteria found on healthy skin, a point of entry, and moisture to grow

  • manure is a good skin conditioner

• prevention and control of infections/lesions

  • footbath programs

    • copper sulfate solutions commonly used

• hoof trimming

  • 2x per year, at dry of and again around 90-120 DIM

  • heifer 6-8 wks before calving

• use hygiene scoring to help determine ideal footbath frequency

Prevention of SARA

• proper particle size in the TMR

  • promotes saliva prod

• feed bunk mngmnt

  • minimize competition

• do not feed excess of rapidly fermentable CHO

• add buffers to the TMR

  • sodium bicarb

  • potassium carbonate

Locomotion scoring

Effect of laminatis on milk yield

Milking Parlor Types and Designs

• What is the desired milking routine?

• Adequate amount of time required to perform the pre-milking work routine on each cow

• Too big will encourage short cuts in the milking routine

• Too small will result in bored workers and early unit attachment

• Who will be operating the parlor? The skill level and motivation level of the people in the parlor will determine how efficiently the milking routine will be implemented

• Will the parlor be used as a place to provide special treatment to cows?

• What is the expected production level, milking interval and cow grouping strategy?

• What sort of work environment do you want to provide for the operators and cows?

  • Support arms for milking units and milk hoses and some do not

  • Support arms carry the weight of the cluster and hoses so that operators do not have to

  • Even weight distribution on each quarter that promotes even milk-out while reducing the number of slips and unit falloffs

Tandem

• one single return lane

• cows stand nose to tail inside individual stalls

• milker has side on vantage point of udder

• cows released one at a time

  • no waiting for slow cows to finish

• good for dairies up to 400 cows

Parallel

• stand parallel to each other

• leaves one access point for the milker to reach udder (rear)

• milking doesnt begin until all cows are in their stalls and they are released from the parlor at one time

  • have to wait on slow cows

Herringbone

• most common design

• cattle at 45 degree angle

• different access than parallel or tandem

• cows are calm as they can see others

• when one cow slow … the others can slow down

Rotary

• like carousel rides for cows

• milking stalls are arranged in large circle on a platform that rotates slowly

• cows walk in and finish milking by the time they complete 1-2 laps

• milker can stay in one place instead of having to wak

• expensive

Automatic milking systems

• prior to 1920, US farmers milked by hand

  • one person = 4 cows per hour

• first commercial robot in Europe in 1990s

• robot milking sys automate the entire milking process and single-box robotic systems can do about 50-70 cows per day

• more flexible for farmers

• cows experience less physical stress

Types of automatic milking systems

Robotic-rotary sys:

• milk groups of cows, much like conventional farm

• enables to milk more cows per hour

• more $$$ than box

Robotic box-milking sys:

• well-suited to individual cow mngmnt and cow care

  • precision feeding → can add feed to diets given in there

• might need additional infrastructure (new buildings, etc)

Holding area Size

• Minimize amount of time cows spend standing in the holding area away from feed and resting areas

• Time will depend on the number of milking's per day, climate and production level

• Recommendations:

  • 60 minutes, 45 minutes and 30 minutes for two, three or four time a day milking

  • Total of about two hours per day

Income Over Feed Costs

• One of numerous financial performance indicators that managers can apply to support profitable decision-making

• Is defined as the portion of income from milk sold that remains after paying for purchased and farm-raised feed used to produce milk

• We must know three parameters:

  • milk yield (lbs/cow/day)

  • milk price ($/cwt)

  • feed costs ($/cow/day)

IOFC on a herd vs cow basis

• IOFC on a herd basis can give a more accurate indication of the financial performance of the herd than calculating IOFC on an individual cow basis

• Example: Difference between produced and shipped milk

• Dairy herd with 360 milking cows, 19 of which are in the sick pen with their milk discarded

  • But fed the same diet as the healthy cows

• Assume that all cows (i.e., sick and non-sick) are fed the diet described in table 1

IOFC on lactating vs dry cows

• In the herd there is a group of dry cows (i.e., no lactating cows) that also needs to be fed, although they generate no income

• Herd A with 86 milking cows and 14 dry cows

• Herd B with 80 milking cows and 20 dry cows

Using IOFC as a decision making tool

• Herd managers might decide to stop milking a cow earlier than expected when IOFC equals zero

  • “as long as it pays its feed, it will be milked”

• Drying cows in advance because of a neutral or negative IOFC  can be more expensive than keeping them milking

• a high proportion of lactating or milking cows will not necessarily translate into greater IOFC

• having a balanced proportion of dry cows, typically btwn 14-16% of the herd, implies that new calving or freshening are expected

• new cows entering the herd should be translated into high-producing lactating cows which should lead to highly efficient cows

IOFC summary

• monitor IOFC freq

  • esp with scenarios of low milk prices, high commodities prices, or both

• est IOFC on both an individual-cow and a lactating-herd basis

• est IOFC considering non-lactating cows

• the best use of IOFC is to benchmark against the goals of the farm itself and not with other farms

  • diffs btwn farms related to multiple factors such as pricing of forages, pricing of purchased or farm grown grains, or milk price

Colostrum Management

• Q - quantify → 10g/L to consider that the PTI (passive transfer of immunity) occurred → greater than 5.5 g/dL when using refractometer

• Q - quality → 50 g IgG/L - over 23% of the Bricks on the refractometer, 18-23% would be a supplemented with other things

• Q - quantity → 150 g of IgG - no specific liquid volume

• Q - quickly → want to feed within the time frame of less than 2 hours after birth, also want to milk the mother in less than 2 hours after calving

• Q - quite clean → want less than 100,000 cfu/mL of bacteria → cleaner the colostrum, the better the chance of survival

Reasons for bad quality colostrum

1. nutrition

2. how quickly the cow was milked after calving

3. genetics/age/breed

4. environment

5. disease status

6. stress and handling

7. water quality (big)

What step of the Qs can you make the biggest difference in?

• the “quite clean”

• the more clean = less bacteria, less bacteria = greater chance of survival

• Measure bacteria using the ATP bioluminescence measure

Things that cows and calves go through during the birth process:

Cow Must:

1. Produce Colostrum

2. Change Diet

3. Make A LOT of Milk

4. Switch Pens

5. Etc., etc., etc.,

Calf Must:

1. Initiate Breathing

2. Regulate Acid/Base Balance

3. Control Own Temperature

4. Begin Metabolic Processes

5. Consume Colostrum

Why do we remove calves quickly after birth?

• your lowest death loss is seen in calves taken from the mother within 2-6 hours

• the longer you wait, the higher the death loss

Right after calving you do what to the calf …

• free the navel of bedding and dirt

• dip the exposed navel in a <7% Iodine Tincture (Iodine and Alcohol, the latter dries it out)

• this disinfects the navel and keeps it from being a source of infection for the calf

Esophageal groove

closes off access to the rumen when a calf suckles, allowing colostrum to bypass the rumen and go straight to the abomasum

10 g/L of colostrum vs < 10 g/L of colostrum

5% difference between how many calves are lost just due to the amount of PTI (passive transfer of immunity) that occurs from the colostrum

Goal with calves:

double the body weight by 60 days of age

Pre-weaning calf diet

• mostly milk

• concentrate included

  • arge chunks of grain that help the calf begin to build its rumen environment (going from essentially being monogastrics at birth, with a large abomasum, to being ruminants with a large rumen)

• when deciding to wean the calf … base off of the % of grain intake, not anything else

• start off on about 4 Qts of milk, then up to 8 Qts to help them gain weight, and then when they reach a decent “ideal” weight, bring them down in the amount of milk in steps (8→4, 4→2, 2→0) (prevents acidosis or scours)

If you feed calves better …

you’ll get better milk production

NOTES ON PRE-WEANING PROGRAM

1. Every farm is different!!

2. Offer starter (concentrate) and water free choice from day 1 of life

3. Can house individually the entire time or in groups

4. Calves should be consuming 1.5 kg starter before removing milk and consume starter for 1-week post-weaning before switching to grower

5. 22-24% protein in milk replacer adequate

• 22-24% protein in starter, 18-22% protein in grower

• Starch content of starter 35-45%

6. Weaning:

• First Step = Reduce Milk by 25 – 50%

• Second Step = Reduce Milk to 50 – 25% of original

• When feeding less milk, may only need one weaning step

Need to feed calves near their body temperature …

body temp anywhere from 101-101.5, so you prepare your feed at anywhere from 100-110.

• want your solids % to be the same every single day when preparing feed

Milk Replacer vs Whole Milk

• cost of milk

• cost of milk replacer

• Milk is 12.5% solids

• whole milk has less protein, less fat, and a majorly different lactose difference compared to milk replacer

• variation in lactose fed = diarrhea, scours, bloat, etc

• rule of four - take the two listed above and multiply by 4 to find out whichever is the better/more economical buy

  • whichever number is lower

• whole milk is also lower in the trace mineral content in comparison to milk replacer

  • mineral content is huge and can save calves/a farm!

Goals for calves/calf farm:

< 10% who get respiratory disease

< 15% who get scours/diarrhea

< 3% (2%) death loss

Group vs Individual Housing for Calves

both have advantages and disadvantages but ! listed in the table, they emphasized this in class so definitely focus on it a bit more!

• you want one hutch width between hutches

Post-wean goals

you want to make sure that animals are gaining weight at an appropriate rate so that puberty can occur at a specific time (bc its body weight based), that way they can calve at the time desired

What do we feed in a post-wean diet and prior to calving?

Post-weaning diet composition

• protein req: goes down as growth slows, need protein for colostrum production

• fiber req: goes up to ensure proper rumen function and buffering, DMI

• energy req goes down to ensure proper body condition

  • higher energy in diet = a larger condition score = harder to breed and likely to have diseases at calving

  • target BCS score to the side - KNOW THIS