coursera week 2 DAIRY PRODUCTION AND MANAGEMENT

It's high yielding and can produce high quality forage to support high levels of milk production.. The main nutritional influences on milk yield from pasture include, high-quality forage

Welcome to the forages section of the Penn State dairy MOOC

I'm Greg Roth, Professor of Agronomy at Penn State and

Department of Plant Sciences

Forages are the non-grain crops that are fed to dairy cows

And common dairy farm forages would be legumes like alfalfa and

clover, or grasses such as rye grass and orchard grass

And others might be grain crops, like corn grown for silage or

small grains or sorghums harvested for forage

Forages are critical on the dairy farm and they play multiple roles

And it's really important that everyone on the farm understand the objectives of

forage management on the farm to achieve its success

On a basic level, forages provide some or the entire ration for

the dairy animals on the farm

But in reality, their role is a bit more complex

Let's review a few of the important roles forages play on the dairy farm

Having a good grasp of these helps us better understand the role of forages and

how we can manage them to achieve these goals

A fundamental role of forages is to provide high quality,

healthy feed to keep animals healthy and maximize their performance

Forages should not be too moldy or

harvested too late when the quality is reduced

And dairy producers should be aware of these issues and

try to avoid them through careful management of their fields and machinery

By managing the forages well and producing crops with high energy and protein levels,

we can often significantly reduce the need for other supplemental feeds

And this will lead to another key role of forages, which is to minimize purchased feed cost, which is an important financial indicator on many dairy farms

On many farms, forages are combined in the ration with supplements or

grains, such as this soybean meal, to optimize production

And these can represent significant cost to the dairy farm

In some cases, an expensive input can be offset with homegrown forages,

and this can have a big impact on these purchased feed costs

This, in turn, can improve what we call income over feed cost

Another role of the forage system is to try to reduce the forage production costs

through both high yields and/or lower inputs

And producers need to carefully select the crops and varieties that are adapted to

farms while scrutinizing crop production inputs to keep costs low

Lower forage production costs can also help improve the farm profitability,

since forages often represent about 50% or more of the feed costs on the farm

If the cost of the production is high for a particular forage,

then the best solution may be to purchase some of those forages

Forages should also strive to provide feed for the various animal groups on the farm

On a dairy farm, there's often different animal groups, like lactating cows,

dry cows, heifers, and calves

And each of these groups have some specific requirements, and

forages grown on the farm can help meet those rations

For example, lactating cows need forages with high fiber digestibility, whereas

dry cows need forages that are lower in potassium and can utilize pastures well

So ideally, the farm's forage system

will have the capability to meet the different needs of these animals

As part of this, the forage system must be designed to provide seasonal availability

of forages, either through grazing, multiple harvests per year, or

year-round storage options

In some parts of the world, animals can graze year-round, but

in many areas feed must be stored for long periods

These storage tactics can be significant cost to the dairy, and

can also contribute to some forage quality issues

On this dairy, we see a well-managed bunker silo is providing corn silage,

which is a high-yielding, relatively low-cost,

consistent feed on a year-round basis for the herd

The forages on the dairy farm must also play a role to manage the nutrients in

the manure that's supplied to the farm

Ideally, dairy farms should have forage crops that utilize the manure and keep

the manure nutrients from contaminating ground and surface water supplies

Crops like grass hay fields or small green cover crops can be very good in this

regard, as they need lots of nitrogen and

potassium and reduce runoff during the winter months in many areas

The forage system must also contribute to managing the soils and pests sustainably For example, soil nutrient levels must be monitored to avoid depletion or

creating excessive levels

We also need to avoid depleting the soil of organic matter and

use tactics like crop rotation, reduced tillage or strip cropping

On this farm, corn silage is being grown using no till and rotated with a small

grain cover crop to reduce erosion, improve soil organic matter levels

So we've learned that the role of forages is complicated on dairy farms and

there's lots of things to think about and manage regarding these issues

Fortunately, there are a number of tools that dairy producers have at their

disposal to address some of these issues

A plan might start with a forage inventory plan

describing the amounts of forages the farm anticipates needing for the year

This should include the estimated feeding and

storage losses which can often total 15% to 20%

Next would be a crop production plan with all the fields identified with projected forage production from each

This helps match the crops with the best soils and helps to plan the crop rotation

A nutrient management plan would be useful to help allocate manure to fields based on the crop needs and soil test levels

This helps to reduce the environmental impacts from crop production and

manure applications

A cropping budget estimates the cost of production for the forages on the farm

And this can help decide whether to grow or purchase forages

And once an overall plan is developed, then it must be executed well and

Annuals: Crops that are grown for a single year or less

Forage: non grain feeds such as grass or silage for cattle, horses and sheep

Nutrient management: a site specific plan for the application of plant nutrients as manure or

fertilizer to meet crop needs and minimize environmental impacts

Perennials: crops that are grown for multiple years

Outside US, 1 tonne/metric ton = 1000 kg

continually refined through reevaluation

Execution of the production plan involves pulling together the skills and

equipment to plant, harvest, store the forages on a timely basis

And this is often a substantial undertaking on most farms

The evaluation phase involves the assessment of yields,

forage quality, soil fertility and profitability

The evaluations are done with tools like forage analysis, soil test reports and

estimates of income over feed cost from our financial advisors

Then each year, based on input from these sources,

the forage production plan is updated and refined

And over time, with careful execution and

planning, many well-managed farms develop systems that allow

them to meet many of the goals that we've discussed with their forage system

Hopefully now you have an appreciation on the fundamentals of forage

production systems on successful dairy farms

In future lessons, we will discuss some of the specifics of successful forage

management on these dairy farms

The forages on a dairy farm can be proudly classified as annuals or perennials

Perennials are those crops that are grown from multiple years

Examples of these would be, alfalfa, clovers, and many types of grasses

In this lesson, we will discuss some of the basic management issues for

perennial forages

Perennial crops have many advantages

They don't need to be planted every year

They can protect the soil over the winter,

and they can help improve the soil structure and organic matter

And they can provide high quality forage with protein, fiber, and

energy to support milk production and growth and development

There's three key components of successful perennial forage production

The first is the selection of the best adapted species and varieties for

the land, and the potential end use of the feed

The second component is careful crop management with appropriate planting and fertilizing of the crop

And the third component is the harvesting and storage of the crop

Let's first discuss the variety and species or seed selection

A good seed choice would result in a forage that can be produced economically and meet the needs of some of the animals on the farm

Now a single farm may grow multiple species,

depending on the soil resources and the intended use of the forage

Alfalfa is a good choice on many dairies

It's high yielding and

can produce high quality forage to support high levels of milk production

But Alfalfa requires soils that drain well, otherwise the Alfalfa plants will

not persist and yields will eventually be reduced

On farms where Alfalfa does not grow well and other options might be a mixture of Alfalfa and grass or perhaps a pure stand grass

Common grass is used for dairy forge include Ochardgrass, ryegrass or

tall fescue

Each of these grasses have specific traits

that make them more adapted to different situations

Ryegrass for

an example especially well adapted to cool climates with moderate winters

Within each grass species, seed companies have to develop varieties

with specific traits that might improve performance

These could include higher digestibility, later maturity, or

better winter hardiness

Many universities like Penn State, test forage varieties and

can provide some unbiased information

A mixture of alfalfa and grass can produce good yields of forage on variable soils Where the soils are well drained, the Alfalfa does well, and

in other areas the grass persists and fills in

This allows producers to grow Alfalfa type forages in variable fields that exist on many farms

The next step is to manage the crop to produce high yields

The first consideration in management is to assess to soil fertility

with a soil test

And apply recommended nutrients as lime and fertilizer

Many legume crops require a soil pH above 6.0 to 6.5 and

optimum levels of phosphorous and potassium

The second step in management is to establish a good crop

with careful planning techniques

For most small seeded perennial crops, this involves seeding no more than a three eighths inch deep in a well prepared seed bed or with a well adjusted no till drill When planting in a tilled seed bed, having a level, firm, and

fine seed bed will optimize seed to soil contact and emergence

When using no till planting,

paying close attention to seeding depth with a no till drill is important

The timing of planting is also critical

For most forage crops the ideal time is in early spring or late summer

After the crop emerges, it should be monitored for insects and weeds and

then treat it if necessary

Harvesting the newly established crop just at flowering

will allow the plants to generate adequate root reserves for rapid regrowth

Earlier harvest to control weeds may be necessary, but it will weaken the plants The third phase of forage management is the harvest and storage of the crop The optimum timing of forage harvest is a compromise between the yield, and forage quality

Often harvesting before the crop reaches maximum yield is the ideal

Because forage quality declines as the crop matures

This graph shows an idealized relationship between forage yield and quality Note how the digestibility declines as the forage yield increases

The ideal stage will depend on the species and the specific feed quality desired For Alfalfa, harvesting at the bud stage to the early blue stage

prior to the development of many flowers as often an ideal harvest stage

Ideally the forge crops should be mowed with no rain forecast but

this could be difficult with some areas

The crops are moved and allowed to dry in the field until they reach

an optimum dry amount of content for the storage system

They're going to be stored in

For those Alfalfa crops stored as Hay,

the optimum storage moisture's 85 to 90% dry matter

For crops being stored at plastic wrapped silage bales,

the optimum dry matter content will be approximately 35 to 40%

For crops that will be in silo in a horizontal silo, like a bunker or pile,

the optimum dry matter will be approximately 30 to 35%

For crops harvested as hay, a round or

square baler will be used to harvest the crop

If the hay is stored dry, the bales will be collected from the field and

moved to a storage location

If hay's destined for silage, then the bales will be wrapped with plastic, and stored at a secure location

For a crop that will be harvested as chop silage, then a forage chopper or

harvester will be used to chop and blow the forage into a truck or wagon

The forage will be then transported to a storage facility where it

will be dumped or blown into an upright structure

In the horizontal silos,

the forage will be spread impact with cooled oxygen from the harvested forage Once the structure is filled, it will be covered with plastic and

sealed to exclude oxygen to promote a rapid fermentation

After about three weeks, the fermentation should be complete and

the silo can be opened and feeding can begin

Open with perennial forages multiple cuttings are made during the year And the forage from subsequent cuttings will be stored in the same silo

An alternative is that separate smaller cuttings

can be stored in horizontal silage bags

Each cutting may have a different forage quality and this should be assessed with the forage analysis before feeding so that rations can be adjusted appropriately This has been a basic overview of forge management from establishment

through harvest

For each part of the process there's many specific details

For more of these details visit some of the links provided with this module

The forages on a dairy farm can be broadly classified as either annuals or

perennials

Annuals are crops that are grown for a single year

Examples of these would be corn, sorghum, or small grains such as rye, or barley

In this lesson we will discuss some of the basic management issues for

annual forages

Annual forages have some advantages

They offer flexibility to change crops each year

They can have high yields, and for some, like corn and

sorghum, they can be harvested in a single, highly mechanised operation

And they can result in relatively consistent feeds,

because of the large yields and harvest under the same weather conditions

As with perennial forages,

there are three components of successful annual forage production

The first is a selection of the best adapted species and

varieties of the land, and the potential end use of the feed

The second component is careful crop management with appropriate planting and fertilizing of the crop

And the third component is the harvesting and storage of the crop

We'll cover the first two points in this is lesson, and Dr

Histoff will cover the harvesting storage in another session

Let's first discuss each species and then variety selection

Corn is by far the most important annual forage on many dairies in the US Corn chop for silage results in yields from five to ten tons per

acre of a consistent high energy forage

And corn can effectively recycle much of the nitrogen and

potassium applied in the dairy manure

It can be stored well and provide a year round feed that is useful for

all the different dairy cattle on the farm

And often the cost per ton of feed is moderate to low compared to other feeds And these factors account for it's popularity on dairy farms

Our key management decision is the selection of a corn hybrid for production The first consideration is to select a hybrid that will mature under the typical weather conditions at the farm

Hybrids that fail to mature can be killed by a frost,

and this will reduce the yield and quality of the forage

A second consideration is to find a hybrid that will produce high yields of a quality forage

Many universities, like Penn State test corn varieties and

can provide some unbiased information

Some corn hybrids, such as these brown midrib or

BMR hybrids are bred specifically for silage production and

have enhanced fiber digestibility which can be important on some dairy farms

To maximize its potential,

corn should be planted in a timely manner to allow to utilize the entire season Corn is usually planted in rows 30 inches or 76 centimeters apart,

although some producers are switching to narrower rows to maximum yields now The crop should also be fertilized to achieve top yields

Fertilizer recommendations are available in resources like

the Penn State Agronomy Guide

Fertilizer nutrium recommendations need to account for

the yield potential of the crop and

nutrients supplied by manure applications in previous crops like alfalfa

This helps to avoid over fertilization which can cause environmental issues

The next important dairy forage are sorghums

Sorghums are diverse and vary from tall forage varieties, used for

single cut systems to shorter sorghum sudans used in multiple cut systems

Sorghum sudans are often used where the growing season is shorter and

the crop can be cut in about 60 days after planting, and

then again in 30 to 45 days if the season allows

Forage sorghum are a single cut crop that require planting in early summer and harvest in the fall

Traditional forage sorghums are tall and high-yielding,

but can fall over late in the season

Shorter sorghums have been developed to alleviate this problem

Sorghum breeders have developed shorter sorghums that are earlier and

also brown midrib types that produce higher quality forage

with less risk of frost before maturity

Sorghums are good options where water is limiting,

as they produce more dry matter per unit of water than corn

Sorghums also require less nitrogen fertilizer and

generally have lower seed costs than corn

Other important annual forages are the small grains

These include rye, triticale, wheat, oats and barley

In some longer season areas, these are winter crops and

can be planted following a full season crop like corn or sorghum

Then in spring when small grain crops harvested Corn or

sorghum can be double cropped after harvest

This rotation can maximize the amount of forage produced on a given amount of land,

but can be challenging to harvest and replant fields rapidly

In short season areas, spring versions of the oats and

barley can be used as forage crops

Subtle differences among these cereals can dictate their choice for

a particular environment

For example, in winter cereals, rye is very winter hearty and early

Triticale can produce high yields and high quality

And barley can produce high quality at later maturity stages,

such as a soft dose stage

With good management, these can produce a quality feed for lactating animals

If quality is less than desired, then they can be used for replacement feed

Winter small grains can also protect the soil from erosion and

reduce the potential for nutrient leaching and runoff

These are import on dairy farms

Winter small grains can also take up considerable nutrients and

help with the nutrient management planning

To optimize yields, winter grain should be planted early in the fall, and

spring grains early in the spring

Often, some nitrogen fertilizer will be required to optimize yield and

protein levels in the forage

This can be supplied with either manure or nitrogen fertilizer

Small grain forages often remove large amounts of potassium so

this nutrient should be monitored and supplied if necessary

This has been a basic overview of annual forage management

Annual forages alone or in combination with each other often play a large role

on modern dairy farms when managed well and harvested at the right time

For more of these CTLs, visit the links provided with this module

Glossary

Acidosis: When the pH of the rumen falls below optimal levels (< 5.5) which impairs microbial

activity and animal health

Continuous Grazing: Keeping animals on one pasture all the time such that plants do not have

time to recover due to frequent re-grazing of new growth

Crude Protein: The total protein found in a feed (including pasture).

Diet Selection: Selecting/rejecting plants or plant parts based on animal preferences

Fermentable carbohydrate: Sugars and starches that are easily digested, such as grain and

molasses

Milk fever (hypocalcemia): A metabolic disease caused by low blood calcium levels.

Milk urea nitrogen: A measure of urea in the milk that can be an indicator of efficiency of

protein digestion

Overgrazing: Grazing a plant too much such that the plant’s energy reserves are removed,

resulting in slower plant growth

Rotational Grazing: Dividing pastures and grazing animals for shorter periods in each paddock

to allow plants to recover and regrow between being harvested (grazed) by animals

Rumen degradable protein: The portion of the crude protein that is rapidly broken down in the

rumen by microbes

Rumen undegradable protein: The portion of the crude protein that escapes microbial

digestion in the rumen

Conversion Matrix

1 inch = 2.5 cm

1 kg = 2.2 lbs

Hello, my name is Kathy Soder

I am a research animal scientist with the USDA agricultural research service

Today, I will be presenting the first of two lectures on grazing management

from the Dairy Production and Management MOOC Series

While the majority of milk produced in the United States is from dairy herds fed

conserved forages such as silage, baleage and hay

There are a number of herds that use grazing as a feeding management strategy

for reducing feed costs, increasing profit margins or

meeting the requirements of a specific milk market

Additionally, while larger dairy herds typically do not graze their lactating

herd, they may graze other categories of animals such as dry cows,

late lactation cows, or heifers

Therefore, understanding basic nutrition and management of pasture is essential for

herds grazing any category of animal

The challenges of managing a grazing system are quite different from

managing a confinement dairy

The manage of the grazing dairy must react quickly to changes in environment,

such as weather, soil, and forage conditions on a daily basis

Managers of confinement dairy systems are usually very production oriented,

so they can profit from high levels of milk production

Grazing systems, on the other hand,

are frequently characterized by lower levels of milk production

However, emphasis is placed on high milk production per acre at a reduced cost since the cows are harvesting much of their own feed and

spreading their own manure

The key to any successful dairy grazing system is providing high-quality

forage in sufficient quantities such that dry matter intake and nutrient intakes

are not deficient, as these are two of the main driving factors for milk production The main nutritional influences on milk yield from pasture include, high-quality forage grown per unit of land, amount of pasture allocated per cow, pasture

management, and quality of supplemental feed to complement pasture nutrition While dairy farmers grazed cows generations ago, as technology advanced,

it was found to be more advantageous from a milk production standpoint,

to bring cows to the barn and feed them under more controlled conditions

However, as economics have changed over the last few decades, some dairy farmers have revisited the use of lower cost pasture as a main forage source

Grazing management today is not the same as grazing management several

generations ago

In the past, cows were grazed in uncontrolled or

continuous pasture system for a long period of time

Because the cows have access to the entire pasture all the time,

they're able to select their favorite forage species and ignore the others

This will result in cows overgrazing desirable species and

decreased forage yield

In addition, due to stressing the forage plants from overgrazing,

this will provide an opportunity for weeds to move in

As a result of this management, one can expect lower milk and forage production Additionally, nutrient deposition will be uneven as cows deposit greater amounts of manure in favorite hangouts such as under shade trees or near water tanks

Unlike continuous grazing, rotational grazing involves dividing large pastures with fencing to graze smaller pastures more intensively for

shorter periods of time

Usually one-half to one day

Then moving cows to another pasture to allow that pasture foraged to rest,

regrow, and regenerate energy stores to improve pasture productivity and

longevity, and decrease weed issues due to improved forage vigor

This system has greater capital investment than continuous grazing,

mostly in fencing and watering systems

Requires a bit more labor to do the daily moves to new pasture, but

still less investment than a confinement system

Since the cows are limited to a smaller pasture area, competition for

forages is greater, and opportunity for

diet selection is lower, which will improve forage use

Forage quality is typically higher since forages are grazed at optimum maturity

If forages get too mature to graze, they can be harvested as silage or

hay, unlike a continuously grazed pasture or harvesting would not be an option The farm manager is able to control the forage tight at which the cows are removed which is crucial to the plants ability to survive

One of the advantages of feeding cows in confinement is the ability

to control the cows diet, resulting in greater milk production

Feed is provided in the feed bunk and cows have a limited ability to pick and choose, especially if a total mixed ration is fed

In addition, herds in confinement are often larger as they're

not restricted by the amount of pasture within walking distance of the barn or milking parlor, the way grazing herds can be limited

However, confinement herds require greater amounts of fuel, labor, and

time, greater manure storage, hauling, and spreading capabilities, and

the potential for greater soil erosion in crop lands due to tillage or

lack of full coverage of the soil surface throughout the year

The type of feeding management used in dairy herds, will depend greatly on

resources, skills, business plans, milk markets, and desires of the owner

Some dairy producers have been grazing cows for decades,

while others become frustrated when pasture does not produce quality forage, due to poor pasture management

Grazing is one option that has helped some smaller family farms

stay in business through decreased costs, feed inputs, and or increased income, such as grass-fed labels or organic milk markets

Now that we've discussed the basic types of grazing systems,

understanding that there are many variations within each,

let's now briefly discuss pasture management

We mentioned previously that we want to manage forages by quickly harvesting the forage, not overgraze the pastures to allow sufficient forage cover,

then resting the plants to allow them regrow

But why is this beneficial?

Most forage plants store energy in either the bottom few inches of the forage, and/or in the roots

This will vary by species, so check with local agronomy experts for

information on local forages

If the plant is grazed too closely to the ground,

this energy storage bank is removed

In addition, too many leaves are removed which serve as solar panels to

capture the Sun's energy to grow

This stresses the plant,

forcing it to draw energy from the root reserves to regrow

Repeated overgrazing will stunt plant growth, decrease root mass, and

weaken the plants

Sometimes to the point of death

Once stunted, these plants do not regrow as quickly, resulting in decreased forage production and number of animals that the pasture can support

This will increase the need for either additional pasture acreage or

supplemental feeding to meet the nutrient needs of the herd

While it is easy to see what happens above ground,

what we don't see is what is happening beneath the soil surface

When forage plants are overgrazed, the root mass and the root depth decrease This decreases the soil's ability to absorb water,

as well as decreases the plant's ability to take up water and

nutrients from the soil, particularly during periods of drought

To illustrate this concept, the plant on the left was allowed to grow for

three months without clipping

It has a very healthy root system

The plant in the middle was clipped to 7.5 centimeters or

3 inches every 3 weeks for 3 months

It also has a healthy root system,

although not quite as dense as the first plant

The plant on the right was clipped at 2.5 centimeters or

1 inch every week for 3 months

This plant has a very weak and shallow root system and may not survive a drought Clearly, management of a profitable grazing system requires

different management skills when compared to confinement systems

There is an art as well as a science to managing a grazing dairy herd

that could only be gained with knowledge and experience

Keeping the pasture feed bunk full of nutritious feed

is one of the most important aspects of grazing nutrition

In the next session, we will discuss nutrition in dairy grazing systems

Hello, my name is Kathy Soder

I am a research animal scientist with the USDA Agricultural Research Service Today, I will be presenting the second of two lessons on grazing

management from the dairy production and management MOOC series

In the last lesson, we focused on pasture management

Today, we will focus on the animal,

to look at the nutritional aspect of dairy grazing systems

While grazing cows is a low cost resource for feeding dairy cows,

intensive grazing systems present challenges to nutritionists and farmers

The forage quality of pastures is usually higher than

the same forage harvested as silage or dry hay due to maturity level of harvest Seasonal variation, species composition such as legumes mixed with grass species, fertilization management and grazing preferences by animals makes supplemental feeding with pasture based systems more difficult

than with confinement systems where forage quality is known

High quality pastures are key to optimal milk production in grazing dairy herds However, there are many questions regarding what defines a high quality

pasture and how we can develop and

maintain high quality forages in sufficient quantities

to meet the dry matter and nutrient needs of lactating dairy cows

High quality pasture has many positive attributes for lactating dairy cows, but

it also has nutritional imbalances and deficiencies

Total protein is usually high in frequently exceeds crude protein needs

of the lactating cow, especially if nitrogen fertilization or

legumes are part of the pasture management

This protein is highly degradable in the rumen

This rumen degradable protein,

or RDP, is rapidly broken down by the rumen microbes into ammonia

Ideally, this ammonia is recaptured into more microbial protein to maintain rumen function and provide protein to the animal further down the digestive tract

However, if energy is lacking in the diet, which can be the case with pasture

based diets, this ammonia cannot be recaptured into microbial protein

Rather it is converted to urea, a less toxic form, and

excreted in urine and milk

Not only is this a potential environmental issue with additional nitrogen excreted in urine, and can have negative effects on cow productivity through elevated milk

urea nitrogen or MUN levels, but the conversion of ammonia to urea

requires energy that otherwise could have been used to produce additional milk For high producing cows, producing greater than 70 pounds of 32 kilograms of

milk per day on pasture, rumen undegradable or bypass protein,

also known as RUP, may be inadequate and a supplemental source of rumen

undegradable protein may be necessary to maintain optimal milk production

The fiber content of high quality pasture may be too low,

particularly in the spring and fall

To stimulate adequate cud chewing and rumination

This may result in reduced milk fat content and

metabolic issues such as acidosis

Some grazing dairies will allow some pastures to get a bit more

mature to increase the fiber content of the diet

However, this will also result in reduced protein and energy of the pasture forage,

so supplemental feeding may be needed to meet those nutrient needs

Other farms will supplement with hay or baleage to provide long fiber

The amount of several minerals including calcium, phosphorus, magnesium,

sulfur, zinc, and salt are usually inadequate in pasture

In general, these minerals should be added to the supplemental feeding program or

to a free-choice trace mineral mix

Potassium and

phosphorous may be too high in some regions relative to nutrient needs,

particularly in areas that historically have had heavy lumen application

High potassium diet can result in milk fever, or

hypocalcemia, while high phosphorous is an environmental concern as it is excreted in the minora and it can get into the water supply

Vitamins A and E are high in fresh pasture forages and

vitamin supplementation is often not needed during the grazing season, but

may be necessary during the non-grazing season when conserved forages are fed

In addition to the high protein content, the other notable nutrient imbalance is

a relatively low fermentable carbohydrate content

The major source of energy for both the rumen microbes, and

the cow, in most pastures compared to the needs of the cow

Therefore, strategic supplementation with grain or other energy sources may be

desirable to maintain milk production, milk components, and animal health

Research at Penn State University has shown that high quality pastures in

the Northeastern United States can support 18-23 kg or 40-50 lb of milk production However, this was a short-term study that did not account for

long-term effects on body condition or reproduction

In addition, many grazing farms target higher levels of milk production or

need supplemental feeds to fill in gaps in forage production such as summer slumps or poor quality forage

Therefore, strategic supplementation of grazing dairy cows is often

needed to maintain animal productivity and farm milk production goals

The most common supplementation strategies are grains for

energy, effect the fiber from forage or high fiber feed ingredients, and

minerals that are deficient in pastures

In addition, some very high producing herds may supplement with fat or

rumen bypass protein source to improve production and components

Before we discuss supplementation,

the first step in a successful grazing system is to provide adequate quantities

of high-quality pasture, which is the cheapest feed source available

If pasture availability is limited,

cows cannot maintain adequate dry matter intake

In addition, they will spend more time walking around searching for more to eat The energy spent walking could have been used to produce more milk

Therefore, we want to make sure the cows get the most

high quality forages possible in every bite taken

When deciding how much area to give cows,

the farmer must consider the following options

How much time with the cow spend in this pasture will she be out half a day,

one day, or longer on the same pasture?

How many cows are on the pasture?

How big is that pasture?

Estimated dry matter intake of group

How much forage is available?

And how much will cows actually consume versus what they will waste or

leave behind?

This last point is important

Cows will not eat every single bite of grass available in a pasture

Some forage will be wasted due to rejection, manure and urine spots and

preference for other plants

It is important to allocate more pasture than is expected to be consumed

probably 50 to 100% over and above expected requirements

For cows to maintain dry matter intake, select the highest quality forages,

avoid manure and urine patches and

allow enough forage residual to maintain plant regrowth

Even with sufficient quantities of high quality pasture,

the nutrient needs of lactating cows are often not met, especially energy

Therefore, strategic supplementation is a crucial part of dairy nutrition

in most grazing herds

Any type of supplement will reduce the cows' intake on pasture

If forage is supplemented,

you can expect an approximate one to one substitution rate

That is, for every pound or kilogram of supplemental forage fed,

on a dry matter basis, you can expect pasture intake to decrease by one pound or kilogram of dry matter

This results in no change in total dry matter intake

One pound or kilogram of concentrated grain on a dry matter basis

will reduce pasture intake by ony one-half a pound or kilogram of dry matter Supplementing with grain or concentrate will not ony result in greater total dry matter intake due to a lower substitution rate, but greater nutrient intake,

especially energy, due to the increased nutrient density of the grains

Substitution rates for biotic feeds may vary depending on source and

nutrient content

Another factor that can influence pasture intake and

grazing behavior is when supplemental feed is fed in relation to the grazing period Some farms will feed supplemental feed in the milking parlour or

immediately after milking

The cows are then turned out to pasture

Other farms will turn cows out on pasture after milking and

feed supplemental feed later in the day

When cows are fed supplements prior to grazing,

appetite will be reduced when turned out on pasture

And just like humans,

when they are less hungry, cows get pickier about what they eat

They may only nibble on the tips of the forage plants or select certain species of plants which result in decreased pasture intake and utilization

When cows are turned out hungry with no supplemental feed prior to grazing, appetite is high

Grazing is more aggressive and cows will be much less selective about what plants and plant parts they eat, thereby increasing pasture intake and utilization

Grazing dairy farmers can use this behavior to meet their farm goals,

whether it is to maximize pasture intake or

stretch pasture resources with supplemental feed

Due to grain prices and availability, farm philosophy and

milk markets, some grazing dairies have gone no grain

Feeding only forages to their cows in the form of pasture or conserve forages but not corn silage

While this can be successfully done, it does take a higher level of management and adaptation to go no-grain

High forage quality is a must at all times,

as there is no grain to fall back on if forages are not of sufficient quality

Cows must be adapted to a no-grain diet, as well

It is not advisable to put cows with high milk production potential

on a no-grain diet

They will continue to try to produce high quantities of milk at the expense of their body condition and health and eventually fall out of the system

Cows should be of moderate body frame, moderate milk production,

with enough body capacity to process high forage diets

Farmers must also make adjustments

Milk production will likely drop but must be maintained at profitable levels

There are some premium markets for grass-fed milk, but

at this time, they are limited to the United States

Farmers must keep a close eye on pasture quality and availability and

often be thinking weeks or months ahead to insure there's adequate pasture available

as well as have a backup plan in place in the event of adverse weather conditions such as drought or flooding

Management of a profitable grazing system requires higher and

different management skills compared with confinement systems

Successful grazers acquire these skills with experience, education and

mentorship from other grazers

Keeping adequate amounts of high quality pasture is one of the most important aspects of nutritional management of raising dairy herds

Thank you for joining us for the grazing management section

More information will be provided in the lesson resources on the MOOC website

Does not have BMR versions

Uses less water

Needs more N fertilizer

Needs more N fertilizer and does not have BMR versions

Uses less water and needs more N fertilizer

Understanding the vitamin needs of the cattle on the farm

Managing the energy levels of the forages to optimize production

Matching the minerals to the protein content of the forage

Planning to distribute manure and fertilizers to the fields where they are most needed

Balancing the ration of the cows

Correct

6

Question 6

Corn silage is popular annual forage crop because

1 / 1 point

the high protein content of the forage

the consistent forage quality and high yields

its responds well to N fertilizer

it has a relatively low starch content

it grows well on poor soils

High starch content

High fiber digestibility

Soil test report

Nutrient management plan

1 / 1 point

The forage quality is often not influenced by maturity

Yields are higher than most other forage crops

Another forage crop can be double cropped following harvest

They are often harvested in the winter

They usually have lower protein levels than corn silage Correct

Amount of pasture allocated per cow

High-quality pasture forage

Correct

14

Question 14

Where do pasture plants (cool-season grasses and legume) store energy reserves used for regrowth?

Stunted plant growth

Decreased forage production

Improved milk production

Increased weed pressure

Correct

Chào mừng đến với phần thức ăn gia súc của MOOC sữa Penn State

Tôi là Greg Roth, Giáo sư Nông học tại Penn State và

Khoa thực vật

Thức ăn gia súc là các loại cây không phải ngũ cốc được dùng cho bò sữa

Và thức ăn cho trang trại bò sữa thông thường sẽ là các loại đậu như cỏ linh lăng và

cỏ ba lá, hoặc các loại cỏ như cỏ lúa mạch đen và cỏ vườn

Và những thứ khác có thể là cây ngũ cốc, như ngô được trồng để ủ chua hoặc

hạt nhỏ hoặc cao lương thu hoạch để làm thức ăn gia súc

Gia súc ăn thịt rất quan trọng trong trang trại bò sữa và chúng đóng nhiều vai trò

Và điều thực sự quan trọng là mọi người trong trang trại phải hiểu các mục tiêu của

quản lý thức ăn gia súc trong trang trại để đạt được thành công

Ở cấp độ cơ bản, thức ăn chăn nuôi cung cấp một số hoặc toàn bộ khẩu phần ăn cho

chăn nuôi bò sữa trong trang trại

Nhưng trên thực tế, vai trò của họ phức tạp hơn một chút

Chúng ta hãy xem xét một số vai trò quan trọng của thức ăn chăn nuôi trong trang trại bò sữa Nắm bắt tốt những điều này sẽ giúp chúng ta hiểu rõ hơn về vai trò của thức ăn gia súc và chúng ta có thể quản lý chúng như thế nào để đạt được những mục tiêu này

Vai trò cơ bản của thức ăn chăn nuôi là cung cấp chất lượng cao,

thức ăn lành mạnh để giữ cho vật nuôi khỏe mạnh và tối đa hóa năng suất của chúng

Thức ăn gia súc không được quá mốc hoặc

thu hoạch quá muộn khi chất lượng bị giảm sút

Và các nhà sản xuất sữa nên nhận thức được những vấn đề này và

cố gắng tránh chúng bằng cách quản lý cẩn thận các lĩnh vực và máy móc của chúng

Bằng cách quản lý tốt thức ăn chăn nuôi và sản xuất cây trồng có năng lượng và mức protein cao,

chúng ta thường có thể giảm đáng kể nhu cầu về các loại thức ăn bổ sung khác

Và điều này sẽ dẫn đến một vai trò quan trọng khác của thức ăn chăn nuôi, đó là giảm thiểu việc mua

chi phí thức ăn, vốn là một chỉ tiêu tài chính quan trọng ở nhiều trang trại bò sữa

Ở nhiều trang trại, thức ăn thô xanh được kết hợp trong khẩu phần với các chất bổ sung hoặc ngũ cốc, chẳng hạn như bột đậu nành, để tối ưu hóa sản xuất

Và những điều này có thể thể hiện chi phí đáng kể cho trang trại bò sữa

Trong một số trường hợp, đầu vào đắt tiền có thể được bù đắp bằng thức ăn tự trồng trong nhà,

và điều này có thể có tác động lớn đến chi phí thức ăn đã mua này

Đổi lại, điều này có thể cải thiện cái mà chúng ta gọi là thu nhập so với chi phí thức ăn chăn nuôi

Một vai trò khác của hệ thống thức ăn thô xanh là cố gắng giảm chi phí sản xuất thức ăn thô xanh

thông qua cả sản lượng cao và / hoặc đầu vào thấp hơn

Và người sản xuất cần phải lựa chọn cẩn thận các loại cây trồng và giống thích nghi với

đồng thời xem xét kỹ lưỡng đầu vào sản xuất cây trồng để giữ chi phí thấp