coursera week 5 DAIRY PRODUCTION AND MANAGEMENT

Hitting target body weights at calving is important, as it helps reduce calving difficulties and supports high levels of feed intake and milk production after calving.. Will lose more bo

Weaning - Removal of milk from the calf

Rumen Papillae - Projections from the lining of the rumen that allow for absorption of nutrients

Immunoglobulins - Transferred from the dam these are large proteins found in colostrum that are important in providing immunity from diseases

Milk replacer - Dry feed that contains similar nutrients found in milk

First calf heifer - Heifer that is calving for the first time

Hello, this is Gabriella Varga

And today we will talk about calf nutrition management from the time

the calf is born to being weaned off of milk

Calf health, growth, and

productivity rely heavily on nutrition and management practices

Every heifer calf born on a dairy farm represents an opportunity to maintain or

increase herd size, to improve the herd genetically, or

to improve economic returns to the farm

The objectives of raising the newborn calf to weaning age are optimizing growth and

minimizing health problems

In this video, we will discuss the development of the calf's digestive

system, learn how important colostrum is for

the immune system, and the nutrients the calf needs to be healthy and grow well

From birth to about two weeks of age, the calf is a monogastric, or

a simple-stomached animal

The abomasum is the only stomach compartment actively involved in

digestion, and milk or milk replacer provides the main nutrients for the calf

Let's first get acquainted with the calf's anatomy

At birth,

the calf's stomach contains the same four compartments found in adult ruminants

However, the calves reticulum, rumen, and omasum are inactive and undeveloped

The newborn's functional stomach, the abomasum is similar to a human stomach

The objective of calf nutrition is to promote rumen development early in life so

that the calf becomes efficient in the absorption of nutrients and

has a much smoother transition at weaning

So let's start at the beginning of the the calf's life, and

talk about how the calf can digest nutrients, such as those that are in milk

At birth, the rumen has little tissue development and

lacks a population of microorganisms

The calf depends mainly on its digestive enzymes,

released primarily from the abomasum and small intestine,

that help bring down the fats, non-fiber carbohydrates and protein

In the young calf, some liquids can bypass the rumen, and

flow directly to the abomasum through the esophageal groove

Calves are initially fed colostrum,

their mother's first milk after calving, for about three days after birth

Within ten minutes, a liquid forms a clot in the abomasum due to enzymes and hydrochloric acid acting on casein and fat in the milk

Clotting binds much of the casein and fat into a clump, or a curd,

to be digested slowly by stomach enzymes over a period of 12 to 18 hours

Curd development allows for limited meal feeding of calves,

compared to other continuous nursing species

The fraction of milk that does not form a curd is called whey

Whey is composed of water, minerals, lactose,

and other proteins, specifically, immunoglobulins

Whey passes directly into the small intestine for

absorption and/or digestion within ten minutes after feeding

From the small intestine,

immunoglobulins can be absorbed into the calf's bloodstream

We will discuss the importance of immunoglobulins for

the calf in more detail later

The lining of the rumen wall in an adult cow

has very pronounced covering of papillae

These papillae are finger-like projections that greatly increase

the rumen surface area, the area through which nutrients can be absorbed

Within a few days of birth, the calf's rumen becomes populated with microbes from feed, the environment in a cow

The papillae development is stimulated by the end products of

microbial fermentation

Specifically butyric acid and to a lesser extent propionic acid

There are two separate components to rumen development

The first is the physical size of the organ

By four weeks of age, if the calf is fed only milk, or

milk replacer, the rumen will be quite small

As milk, or milk replacer, is fed in increasing amounts, the abomasum grows in size, but the rumen remains proportionally small and grows only moderately The longer a calf is fed large amounts of liquid feed,

the greater the restriction on rumen growth relative to the size of the calf

Lack of rumen development causes a slump in growth rates after weaning

The second aspect of rumen development is the elongation

of those rumen papillae and the thickening of rumen walls

Feeding management can drastically affect their development

A calf fed grain, in addition to milk, shows a great deal more papillae

development and a much thicker, darker, and a more vascularized rumen wall Now, compare a third calf fed milk and good quality hay from three days of age Despite eating moderate amounts of hay,

the papillae are not developed at all and the rumen wall is quite thin

This is because the digestion end-products of hay include more acetic acid,

which rumen walls do not use for papillae growth and development

Calves with access to large amounts of roughage will have

a considerable increase on rumen size

However, this is due largely to stretching,

not real growth of the rumen tissue

Feeding calves the correct amount of high-quality colostrum

immediately after birth, plays a critical role in the health of the calf

Colostrum, defined as milk removed from the mammary gland in

the first 24 hours after birth, contains immunoglobulins that,

when absorbed by the calf's gut, helps the calf to resist disease challenges Calves that receive adequate amounts and quality of colostrum,

grow better and are much healthier

The immunoglobulins found in colostrum are large proteins

Calves have openings in the small intestine to accommodate the proteins absorptions, but these openings close shortly after birth

Three types of immunoglobulins can be found in colostrum

Immunoglobulin G makes up 70 to 80% of the immunoglobulins,

and helps identify and destroy invading pathogens

Immunoglobulin M comprises 10 to 15% of immunoglobulins, and

serves as the first line of defense against infection

And then finally, immunoglobulin A comprises the remaining 15% of

immunoglobulins in colostrum, and protects the mucosal surfaces,

such as the intestine, from invasive pathogenic bacteria

Colostrum also contains vitamins, minerals, energy, and

proteins needed for calf metabolism, growth, and for

additional stimulation of the calf's immune system

To make sure that the calf receives immunity from the dam,

colostrum management should focus on three factors immediately after birth How soon, how much, and the quality of the colostrum

Colostrum should be fed within one hour after birth

Approximately 35% of ingested immunoglobulins can be absorbed when calves are fed colostrum immediately after birth

But this declines to less than 5% absorption of

immunoglobulins when calves are fed 20 hours after birth

Feed Colostrum at a rate of 12 to 15% of the calf's body weight

Large breed calves, such as Holsteins weighing more than 90 pounds at birth, can be fed four quarts at birth

Feed calves weighing between 50 and 90 pounds,

such as Jerseys, three quarts at birth

If possible, feed an additional two quarts to all calves 12 hours after birth

Do not allow calves to suckle the dam to obtain colostrum

Although, suckling does enhance absorption,

research has demonstrated that 25 to 40% of calves left with the dam

will not ingest enough colostrum to attain adequate levels of passive immunity Use high-quality colostrum

Colostrum should have more than 50 grams per liter of immunoglobulins, this equates to the green reading on a colostrometer

A colostrometer measures the specific gravity of colostrum prior to feeding

The quality of colostrum is determined by the amount

If a cow produces more than 18 pounds of colostrum,

the odds are less than 50% that it will contain sufficient immunoglobulins

Dry period length

If a cow has a dry period of less than 45 days, often have poor quality colostrum,

as well as those animals that experienced poor nutrition or

heat stress during the dry period

The breed

Holsteins have poorer quality colostrum than other breeds

Colostrum from Holsteins typically are lower in immunoglobulins than colostrum

from Jersey cows

And then, the age of the cow

Older cows tend to have more immunoglobulins than first calf heifers,

as they have been exposed to a greater number of pathogens

Calf Nutrition and Management, Part 2

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After a few days of colostrum feeding,

there are several liquid feeding options available

These include whole milk, milk replacers, waste milk, and

fresh or fermented colostrum

Any of these are excellent feed sources when available and

if it fits into the calf raising program

Whole milk can be the primary liquid feed for calves, if it were dried whole milk

would contain 29 to 30% fat, 25 to 26% protein

Whole milk will supply ample protein and energy for calves,

if one to two pounds is fed for every ten to twelve pounds of body weight

However, due to its composition,

whole milk may be deficient in trace minerals and vitamins

This can be remedied by feeding a quality calf starter

in addition to liquid feeding

There are many excellent milking places available for calves

Protein levels in milk replacers typically range from 18 to 22 percent

New formulations designed for

intensive feeding programs contain 28 to 30 percent protein

The main sources of energy in milk replacers are lactose and fat

Lactose is the best source of carbohydrates, and

milk replacers generally contain 40 to 50% lactose

Fat sources in milk replacers include lard, tallow,

stabilized greases, and hydrogenated vegetable oil

Higher fat levels in milk replacers may decrease prevalence of scours

Fat levels vary from 10 to 22 percent in milk replacers and in general

So what do milk replacer with twenty percent fat?

Additional information on methods of calf feeding, colostrum quality and storage and liquid feeding options can be found in the reading material for this lecture

Calf managers should introduce dry feeds and

water to calves within 3 to 4 days of birth

Feeding a commercial calf starter, or one mixed on the farm,

stimulates early rumen function and development, allows for earlier weaning,

and supplements the nutrition provided by the liquid feeding program

Two starters that contain between 18 and 20% food protein

And when selecting a calf starter, consider the following

Physical form select whole coarsely ground cracked crushed roll steamed or

flaked textured grains

The pallet quality, avoid pellets that are too hard or too soft

Pallets at both extremes will affect intake and avoid fine particles

And then consider molasses or molasses based products

Which should be included at between 5 and 8% of the total mixture

Begin offering starter at three days of age

Calves should be eating some starter by five to seven days of age

By the second week, calves should be consuming

0.25 to 0.5 pounds per day at three weeks of age

If free choice water is available calves will often double there dry

feed intake which coincides with a much more active vermin

Water is critical nutrient for calves and

should be offered beginning at 3-4 days of age

In order to digest feed rumen bacteria must have water

Milk and milk replacer do not qualify as water since they bypass the rumen

Calves should consume 8-10 quarts of water per day at weaning

Weaning age varies from 4 to 8 weeks of age depending

on liquid feeding strategies

Age, however, is not the primary criteria for weaning a calf

Weaning decisions should be based on the dry feed intake of the calf

When a calf consumes 1.3% to 1.5% of it's body weight as fry feed, it

is consuming enough nutrients to maintain it's weight, and grow without liquid feed For large breed calves this translates to weaning when the calf consumes 2 to

2.5 pounds of calf starter per day

For three consecutive days

For healthy calves, reduce liquid feed consumption by 50% per

day one week prior to desired weaning date to stimulate starter intake

Once weaned, keep calves in individual housing for

approximately 7 to 14 days to observe calf health and feed intake

Do not attempt to wean calves less than four weeks old

After weaned from liquid feeds, calves should quickly consume between four and five pounds of calf starter daily

Calves may be moved to group housing at seven to eight weeks of age, or

one to two weeks after weaning

During the first two to three weeks of group housing,

try to keep the ration the same as before weaning

Post-weaning groups of four to six calves are preferable for

one to two months after weaning

With good management, groups of eight to ten can work as well

After weaning, begin incorporating good quality hay into the diet

The general recommendation would be to wean calves at 5 to 8 weeks of age, and offer hay starting at week 8

Forage is important at promoting growth of the muscular layer of the rumen and maintaining the health of the rumen epithelium

Although research has shown that calves consume forages prior to weaning,

forages are not necessary until a time when a calf consumes four to

five pounds of high quality starter, which is typically after weaning

Monitor starter consumption to ensure that hay is not being overeaten

Fermented forages can be fed to calves

But it is not recommended for calves less than three months of age

Proper feeding and care of young calves is the first step in raising healthy,

productive replacement animals to enter the milking herd

So in summary, feed four quarts of high-quality colostrum within the first

six hours to provide calves with essential nutrients and antibodies

Match milk replacer to growth and weaning age goals to meet the calves' needs, and

to balance feed costs and animal performance

Offer a palatable calf starter by three days of age to

stimulate rumen development and allow weaning by four to six weeks of age Provide calves with a clean, dry, draft-free housing that protects them from

harsh sun in the summer and cold winds in the winter

From three days of age, make fresh, clean, free-choice water available, and

then work with your veterinarian to ensure that calves receive adequate vaccinations

Hello, my name is Gabriella Varga and I am Professor of Animal Science

In this video we will be discussing the importance of heifer nutrition and

management from weaning to breeding

We will discuss critical phases of growth for the dairy heifer, the importance of good facilities, and how nutrition plays an important role in getting a healthy,

well grown heifer, ready to be bred, and prepared to have her first calf

A number of factors go into meeting these goals

The first of which is that Heifers must get off to a good start as calves

That means good colostrum management and disease control

We mentioned in our previous video that rumen development is critical

So calves must be provided a good, palatable calf starter and

have access to fresh water

Calves should be weaned after they have consumed two pounds of grain per day for three consecutive days

Holstein heifers should grow 1.7 to 1.9 lbs per

day before puberty, and should reach 85 to 90% of mature body

weight by calving, or a minimum of 1250 lbs,

to be able to achieve optimal first lactation milk production

Age at first calving should be between 22 and

24 months of age to minimize heifer raising costs and

to maximize their production during the first lactation

However, it is important to emphasize that heifers need to grow in height,

not just weight, because height is correlated with their frame size, and

can really impact risk for calving difficulties

Therefore, heifers should reach a height at the withers between 51 to 55 inches prior to calving

After weaning, heifers really should be grouped by weight, not by age

During this time it is important to monitor body weights, heights,

and body condition scores

Weights obtained with a body weight tape around the heart girth

are reasonably accurate

A body condition score of 3 on a 5 point scale is ideal

Heifers at this age and

size should not have a lot of extra flesh around the rump area

As indicated earlier, a good rate of growth for weaning to breeding

is over two pounds per day for the holstein or similarly sized breeds

Let's look at some opportunities on the farm that will help make the transition

better for the heifer after weaning

The following practices can really help reduce the stress placed on these heifers during and after the weaning period

A small-group housing facility for three to five calves should be used for

at least a month immediately after the postweaning period

This postweaning area should be similar in housing type and

environment compared to the grow out facility and located in a similar area

This allows for regular feeding and

observation of the two to three month old group, while feeding those younger calves Large super hutches, located adjacent to the calf hutch area, or

an open-front shed with an outside yard adjacent to the calf hutch area,

can be used in conjunction with small hutches

Building with inside individual pens should also provide for

a group pen at least 12 by 12 feet for three to five calves

Pens should always have a continuous supply of frost-free water

At least 18 inches of bunk space should be provided for

each calf, with stanchions or dividers to define the eating positions

When weaning time arrives the liquid feed portion of the young calves' diet

is reduced

It is necessary to provide them a free choice grain mixture and

an ample supply of high quality forage

To reduce the stress associated with weaning, calf starter is generally fed for two to three weeks after weaning

After weaning,

we should see calves with starter intakes between five to six pounds per day And this is the time we begin to feed a good quality forage

Feed free choice high quality second or

third cutting mixed hay that is fine stemmed and mold free

This can be a good quality grass or alfalfa or a mixture of these two

Silage and pasture have generally not been recommended for

calves less than 400 pounds because it has been thought that the calf

cannot readily consume enough dry matter, in the form of wet forage

High quality forage can comprise a significant amount

of the energy needed by the young heifer

Grasses containing 14 to 16% crude protein,

and no more than 60% neutral detergent fiber can make up a significant part

of the heifer's diet before breeding, so long as that fiber is fairly digestible

Corn silage can also make a portion of the heifer's diet, but the amount of grain fed will depend very much upon the age of the animal and the forage quality

Total mixed rations can also be fed to heifers after two months of age

Feeding complete rations encourages the heifers to consume

several small meals during the day, and

leads to better digestion of feed and utilization of that feed

The advantages of total mixed rations for these heifers are that

all the needed ingredients are in the desired proportions

Time and labor are reduced

And competition among animals is minimized

The young heifer from weaning to six months of age is not capable of consuming and fermenting large quantities of feed and forage, and

therefore does not produce large amounts of rumen microbial protein

Therefore, at this age, protein is a nutrient that limits growth

Heifers requires specific amount of protein daily

And for heifers, total protein has been shown to the equally as important

as the various protein fractions

So we want to balance primarily for crude and soluble protein

14 to 15% crude protein for heifers before puberty

based on a 2.15% body weight dry matter intake per day

About 13 to 14% crude protein after puberty for

heifers based on 1.65% body weight dry matter intake per day

Maintain the ration at least at 30 to 35% soluble protein

Rumen undegradable crude protein levels in excess of 25 to 30% are not required Use feed sources based on price and availability

And not feed specifically designed for high bypass protein

Young heifers with small rumen will respond with lean tissue growth

when they are fed a blend of high-quality protein sources

Protein sources could be a blend of processed soybeans,

canola, corn proteins, and animal proteins

It should be noted that large amounts of high-protein grasses or legumes

containing a lot of soluble protein and degradable protein are not recommended

If such forages make up a large portion of the diets,

the heifer will not utilize all this protein

And it will be wasted, and growth rates will not be optimal

Heifers should be supplemented for vitamins and minerals according to their

needs based on the National Research Committee requirements

Examples of diets for heifers from weaning

to post-breeding age are provided in the supplemental reading for this video

From six months to breeding,

forages usually make up the majority of the ration

Grain is supplemented to balance the ration for

the desired amount of daily gain

Corn silage should be limited to no more than 50% of forage intake

Excess energy during this period can hinder mammary development and

ultimately decrease the potential for milk production

From breeding to calving forages should be maximized in the ration

Feeding only enough concentrates to meet the animal's requirements

Heifers should be started on the dry cow diet approximately 60 days prior to

freshening

Specific information on feeding heifers prior to calving is provided in

the second dry cow video

The energy requirement of the heifer will be influenced by the size, growth rate and environment of the heifer

There are two feeding strategies to meet the energy requirements of

growing dairy heifers

First, diets can be formulated at variable energy densities and

fed free choice to allow the heifer to select her energy consumption

In the second strategy, heifers' diets can be formulated at a fixed,

generally higher energy content and

precision-fed to specifically meet the heifers' energy requirement

Regardless of feeding strategy, heifers should be fed to allow for

1.75 to 2 pounds of average daily gain or

approximately 130 kilocalories of metabolizable

energy per pound of metabolic weight

During the time around puberty between 550 and 650 pounds for

large breeds, it is critical that heifers are not over fed energy

The growth rate of the mammary system before puberty is much faster

than the growth rate of the body and the size of the mammary gland and

the ducts in the gland actually increase in size at this time

Therefore, excessive energy intake prior to puberty can have

a negative effect on the mammary system and decreased subsequent milk production For large breed heifers, the optimum calving age is 22 to 24 months

Smaller breeds that mature faster such as Jerseys, Airsures,

and Guranses can successfully calve at 22 to 23 months of age

Production data research suggests calving heifers at 23 to 24

months of age is optimal for first lactation milk yields

Dairy replacement heifers do have the potential

to calf at 19 to 20 months of age, which can lower raising costs

However, heifers calving at young ages may experience calving difficulties,

metabolic disorder, and

have inconsistent lactation performance, which can really limit lifetime profit

Calving dairy heifers at ages younger than 22 to 24 months

is possible but requires intensive management programs

Hitting target body weights at calving is important,

as it helps reduce calving difficulties and

supports high levels of feed intake and milk production after calving

For Holsteins, a post-calving weight of 1,250 pounds is ideal

This table shows target body weights for

various breeds at different ages at first calving

So in conclusion, in this video we discussed the critical phases of

the growth of the heifer, the importance of good facilities and

how nutrition plays an important role in getting a healthy well-grown

heifer ready to be bred and prepare to have her first calf

Hello, my name is Gabriella Varga, and

I'm a professor of animal science from Pennsylvania State University

We will be discussing feeding and

management of the dairy cow prior to calving

In this first video, we will focus on the management and

general needs of the pregnant, non-lactating cow prior to calving

Proper management and nutrition of the dairy cow transitioning into lactation is very important for obtaining a healthy calf, increased reproductive efficiency

and optimal milk production in the following lactation

These can be achieved by feeding balanced diets, providing good cow comfort and insuring the cow is in good body condition before and after she calves

We'll spend more time later discussing the importance of good body condition During the last six weeks before she stops lactating and gets ready to have her calf,

it is very important that the dairy cow is fed to meet her nutrient needs for

the level of milk produced

The producer does not want the cow to gain body condition during

the end of her lactation that will get her too fat

We try off the cow 50 to 60 days prior to calving to cause or

to switch nutrient use for milk production to growth of the calf within the uterus The fetus grows more during the last three months of gestation than any other time

So therefore, all extra nutrients the cow consumes during the dry period

above her maintenance requirements go towards growth of the fetus

A dry cow's nutritional needs are generally much lower than a lactating cow

because she's not using nutrients to maintain milk production

The veterinarian and nutritionist help the producer in

assessing the body condition of their cows, are they too fat?

Are they too thin?

For example

Body condition score is a subjective measure of subcutaneous

fat thickness, and a reflection of energy reserves

When cows are to be dried off, so they stop lactating, they should be between

a body condition score of 3.25 to three five on a scale of one to five

One being very thin, and five, extremely fat

This next illustration shows a spectrum of condition scores of cows and

how cows can lose weight, and also gain weight

Cows with proper body condition are less likely to have problems of calving

The goal is for cows not to lose more than one condition score after calving

Penn State and Cornell researches have demonstrated that cows with

body condition greater than 3.25 prepartem have greater risk of ketosis and

produce two to five pounds per day less milk the first three days of

milk than cows with a body condition score less than 3.25

Feed intake of most cows decreases seven to ten days before calving

Dry cows can be expected to have daily dry matter intake

equal to 2 to 2.2% of their body weight

Therefore a 1350 cow would consume 27 to 37 pounds of dry matter each day However, cows that are over conditioned before they cab eat less before and

after calving with feed intake dropping sooner to a greater extent

before calving then optimally body conditions house ready to calve

As a result, fatter cows mobilize body fat to a greater extent

compared to cows where feed intake is not compromised as greatly before calving This greater mobilization of body fat causes excessive fat

to accumulate in the liver of these cows, which further compromises

the liver's ability to make glucose to support milk production

Thus, these cows have a higher likelihood of developing fatty liver and

then develop other diseases that might compromise their health after calving

It is recommended that cows be managed to modify body condition later in lactation and achieve the desired calving body condition score at that time,

rather than during the dry period

If cows are becoming too heavy in late lactation,

the energy content of the diet should be reduced at that time

Dry cows should be housed in an area where they can be observed easily and

moved to the maternity pen when presenting signs of calving

Dry cows need a minimum of 24 inches of feed bump space per cow, but

preferably 30 inches

When feed bunk space is limiting, cows eat less dry matter or eat larger and

fewer meals

Therefore, stocking density is recommended to be no greater than 80 to 85%

During this time frame cows naturally have a lower immune function and

are more susceptible to infection such as mastitis and neuritis

Limiting the resting space increases the time cows spend standing and predisposes them to hoof issues and increased incidence of lameness after calving

To reduce stress, stocking rates should be near 80% of the capacity of

free stall barns, with a minimum of 100 square feet recommended per cow,

and 120 square feet for the maternity pen

Heifers compete better with other heifers and have higher dry matter intakes and longer resting times when housed separately from mature cows

This may be in facilities such as a bedded pack, free stall, and out on pasture

Cows are social creatures and establish a social hierarchy of boss and

subordinate calves

Minimize the number of pen movements or addition of cows to the group

to minimize the amount of social upheaval that occurs with these new additions

If herd size allows Cows should remain in the same

group throughout the last 30 days prior to calving

For herds where this is not possible, new cows should be added

no more frequently than once weekly to the close-up dry cow group

It has been shown in research trials that dry cows benefit from good heat

abatement management

Heat stress decreases feed in take and results in greater metabolic disease and

lower milk production therefore providing fans and

sprinklers to cool cows is critical during the dry period

Water quality and availability is critical for all cows

Generally, four to five pounds of water ar required per pound of dry matter consumed

On average, dry cows require about 13 to 15 gallons of water per day

There are many strategies that work for feeding dry cows

Whether it is a high fiber diet that is low in energy with hay or straw

The goal should always be to provide high quality feed sources,

consistent availability of feed, adequate bunk space, and a comfortable environment

In our next video, we will discuss in more detail specifics of feeding dry cows

So in conclusion, for optimal management of the dry cow,

make sure cows are in proper body condition before dry-off

Manage cows so no more than 10% are too fat or too thin

Fat cows eat less, produce less milk the first 30 days in milk, and

have greater health problems, and generally take longer to breed back

Make sure cows are comfortable

Provide a minimum of 100 square foot per cow, or

11 square meters per cow in dry cow and calving areas

Provide a minimum of 24 inches per cow of bunk space

30 inches per cow is best

Provide adequate high quality water

Good quality forages, and feeds to ensure cow eat well

Thank you for listening to this discussion on dry cow management

Our next video in this series will focus on the nutritional needs of the dry cow

Hello again, this video continues our discussion on management of the dairy cow

We will focus on the nutritional needs of the pregnant, non-lactating cow

There are many feeding strategies that would work for feeding dry cows,

however the goal should always be to provide high quality feed sources,

consistent availability of feed, adequate bunk space, and a comfortable environment Dry cows may be fed in two or one group feeding system

What is a two group system?

It's the most common dry cow program

The dry period is 60 days in length, and

the cows are split into a far-off group, 60 to 21 days prior to calving

And a close-up group, 21 days to calving

And the diet is formulated specifically for each group

So how are far-off cows fed?

Well, the diet to these cows will consist primarily of forages such as corn silage, straw, grass, hay, and some combination of silage

Diets fed to the far-off group can be of lower energy density than

those given to the close-up group, because we are trying to control

the level of energy supplied, in order to prevent the cows from getting too fat

So what is best for a close-up group?

The goal of this phase is to increase the nutrient density of the diet

to prepare the cows for lactation

This diet has an energy level intermediate between that

of the far off dry cow diet, and the fresh cow lactating

diet approximately 0.7 Mcal of NE/lb of dry matter

The advantages of this feeding program are,

to improve energy balance and liver function around the time of calving

To aid the rumen in adaptation to the lactating diet, and

to provide adequate energy as dry matter intake decreases prior to calving

However it does mean that cows have to move more often from pen to pen,

more rations have to be mixed increasing labor and feed costs, and

may overfeed energy and provide less rumen fill at calving

So that's the two group system, what is a one group system?

Well, cows are all housed as one group, fed the same diet for

the whole length of the dry period

Much of the focus in close-up rations

has centered on the energy density of the diets

According to the 2001 Dairy Nutrient Requirement for

dairy cattle, a 1,500 pound cow in the last few weeks prior to calving

would only require 15 Mcal of NE/L per day

If that cow consumes 28 pounds of dry matter,

the energy density of the ration would only

need to be 0.53 Mcal of NEL lactation per pound of dry matter

By not feeding energy in excess of requirements, it is thought that the cow will be at lower risk for the development of metabolic diseases post calving Advantages of a one group dry cow system

The number of times cow moves are reduced every time a cow is moved,

she will be stressed especially over her new pen mates

This stress can reduce intake, cause more metabolic problems, and

elevate fat mobilization

This eliminates the problem of early calving cows being moved from one

pen to another, and put into a close-up diet only a week prior to calving

It also reduces the number of ration changes and mixes, and

this lower in cost when cow's transition from the dry period to the milking ration,

it is a low energy diet

0.6 metcals, NEL per pound of dry matter,

provides room and fill around the time of calving

However, because of higher fiber may be less palatable,

especially if poor quality forages were fed and or, because of straw usage

Straw or dry hay must be processed to less than two inches in length or

sorting will occur resulting in poor cow performance

In addition, feeding a low potassium and calcium diet

will help to improve calcium homeostasis preventing hypocalcemia

The bottom like for feeding dry cows, either one of these feeding systems

can work depending on the management of the farm, and

will be determined primarily by availability of facilities and labor

How is the cow different in her nutrient needs when she's not lactating and pregnant, compared to when she is lactating?

Since the cow is not making milk,

she still has to maintain her normal nutritional needs

During the 60 days prior to calving,

her nutritional needs increase because she's carrying a calf

Therefore she needs to have adequate energy to supply glucose to the calf,

as well as her bodily functions

Protein is critical at this time as this nutrient is needed for

the calf to properly grow in utero, and for

the cow to prepare her mammary gland to start making milk

Vitamins and minerals are critical in all stages of the cow's life

However, prior to calving there are tremendous physiological demands on her body, especially for calcium for milk production, muscle tone,

and helping to expel the fetus

Now we will discuss in more detail, the major nutritional needs of the cow during the few months prior to having her calf

It's important to make sure that cows are comfortable, have adequate bunk space

to allow them to eat the nutrients they need on a daily basis

Cows reduce their intake seven to 10 days prior to calving, so it is critical

that they can eat all the nutrients they receive in their daily ration

The reason for the intake depression may include changes in hormonal status,

ketones in the blood that increase as the cow begins to use body fat,

immune suppression, and perhaps, a large calf inside the cow

The nutrients that are important during the dry period

that we will discuss include energy, protein, and vitamins and minerals

We will start our discussion of the nutrient needs of the dry cow with energy

During the dry period,

the energy needs of the cow differ from those during lactation

The cow no longer needs energy to produce milk, however she still needs energy for maintenance, pregnancy, walking, and to maintain her body condition

There is a high nutritional demand for fetal growth

60% of the fetal growth occurs the last two months of gestation

If sufficient nutrients such as energy are not provided in the diet

in adequate amounts, they will be drawn from the cow's body

So we want to make sure there are adequate glucose precursors in the diet,

such as starch and sugar

When the cow's not lactating, she is eating about

half the amount of dry matter she would normally consume when she is lactating, therefore we really need to make sure that the energy density of the diet is adequate

to meet the needs of the growing microbes to make microbial protein

In addition, nutrients are needed to maintain

good growth, such that their absorptive capacity is

ready to meet the demands of the increase in dry matter intake after calving

We also have to remember that the gut tissues and

the liver are not working as hard during the dry period

So we need to make sure they are prepared to increase in size and

workload, prior to calving with adequate energy sources in the diet

Therefore including as many of the feed ingredients and the ration precalving,

as she will receive post calving will allow for the rumen bacteria, [INAUDIBLE],

to go through adaptation before the demand for milk production comes

This can be achieved in both of the feeding programs we discussed earlier

Energy concentration also needs to be higher for first calf

heifers because of their lower intakes and extra energy needed for growth

Dietary protein quality and

quantity are also important for the success of the dry cow feeding program

Underfeeding protein may lead to suppressed immune function, and

decreased availability of carrier proteins needed for efficient metabolism

As the cow gets closer to calving, the calves needs for glucose and

amino acids also increase

If the cow is short on protein, she begins to mobilize muscle tissue and

we do not want to deplete her maternal protein reserves that she will need for

making milk

Protein are also important for good hormonal status

Total blood protein decreases as the cow approaches calving

This is because the calf is taking more of the protein, and

at the same time the cow is eating less

The high demand for glucose at the initiation of lactation

cause another wrinkle in the cow's protein status

Thus her body's protein in the form of skeletal muscle, is mobilized for

glucose production

Therefore, good quality protein sources that provide the essential amino acid

needs of the cow, are critical in the dry cow feeding program

Heifers require more crude protein in the diet than mature cows

This is due to the lower feed intakes,

and higher protein requirements to accommodate their growth

Although it appears that cows could be fed diets with less than 12% crude protein, for the majority of the pre fresh transition period

This is not recommended since it is believed that 12% crude protein

is the minimum needed to maximize fiber digestion and

microbial protein synthesis in the rumen

Because the drop in feed intake accelerates as calving approaches,

the need for greater percentage crude protein in the diet also accelerates

So crude protein requirements for mammal development are not trivial, and

increase crude protein need in the diets by 1 to 2 percentage units

If cows and heifers are intermingled and fed the same diet prepartum,

the diet should be formulated to meet the needs of the heifers

If they are housed separately, then separate diets could be formulated for

each group

Considering additional requirements for mamic growth,

heifers need approximately a 1000 grams of metabolizable protein per day

This is the protein that is actually absorbed by the intestine of the cow

This is equivalent to 1400 grams of crude protein

Cows need approximately 860 grams of metabolizable protein per day

It is best to make measurements of dry matter intake on the farm so

that percentage crude protein in the diet can be calculated

Providing adequate amounts of minerals and vitamins to the dry cow

is necessary to minimize health problems around freshening time

Calcium, potassium, magnesium are critical in the prevention of many metabolic problems that occur after calving

Adequate amounts of calcium, selenium, vitamin a and e, iodine,

copper are necessary to prevent problems with the cow retaining her placenta

in her uterus after she gives birth

Copper, zinc, selenium, and vitamins A and

E all play a role improving a cow's immune response

Feeding adequate amounts of minerals and vitamins during the dry period is

necessary to give the cow the best chance to fight off many diseases

In an upcoming video, Doctor Van Saun will discuss metabolic diseases of dairy cows And nutrients, such as vitamins and minerals,

that help in the prevention of these diseases

In conclusion, for optimal nutrition of close-up dry cows, to benefit the health

of the cow and her calf, it is important to maximize dry matter intake,

minimize cow movements and overcrowding, provide adequate energy,

protein, vitamins and minerals and expose transition cows to

the same feeds that she will receive in the lactating ration

Thank you and in our next video we will discuss calf feeding and management

Milk and grain

All of the above

Greater than 25 months

none of the above

Correct

6

Question 6

Dry cows need a minimum of feed bunk space during the dry period:

60 day dry period

A far-off and close-up group

One diet for all cows

60 day dry period and a far-off and close-up group

Incorrect

8

Question 8

Advantages of a one-group dry cow feeding system include:

1 / 1 point

Cows are moved many times

Increases the number of ration changes

Increases the incidence of early calving

Provides rumen fill around the time of calving

They are too fat

All of the above

The calf is taking more protein at the same time the cow is eating less

There is a lower demand for glucose as lactation starts

Skeletal muscle is mobilized from the dam for glucose production

The calf is taking more protein at the same time the cow is eating less and skeletal muscle is mobilized from the dam for glucose production

Will lead to an increased immune function

Greater incidence of metabolic diseases after calving

Reduces the amount of amino acids required by the fetus and mammary gland

Greater incidence of metabolic diseases after calving and reduces the amount of amino acids required by the fetus and mammary gland

Making sure cows are eating well

Minimizing cow movements and overcrowding

Providing adequate energy, protein and vitamins and minerals

Exposing cows to the same feed ingredients that are in the lactating cow ration

All of the above

Will lose more body condition after calving

Make less milk after calving

Have greater risk of ketosis after calving

Eat less than thin cows

All of the above

Correct

Cai sữa - Loại bỏ sữa từ bê

Nhú dạ cỏ - Hình chiếu từ lớp lót của dạ cỏ cho phép hấp thụ các chất dinh dưỡng

Immunoglobulin - Được chuyển từ đập này là những protein lớn được tìm thấy trong sữa non,

rất quan trọng trong việc cung cấp khả năng miễn dịch khỏi bệnh tật

Chất thay thế sữa - Thức ăn khô có chứa các chất dinh dưỡng tương tự có trong sữa

Bò cái hậu bị đẻ lần đầu - Bò cái tơ đang đẻ lần đầu

Xin chào, đây là Gabriella Varga

Và hôm nay chúng ta sẽ nói về việc quản lý dinh dưỡng cho bê từ khi

con bê được sinh ra để cai sữa

Sức khỏe của bê, sự phát triển và

năng suất chủ yếu dựa vào dinh dưỡng và thực hành quản lý

Mỗi con bê lai sinh ra trong một trang trại bò sữa đại diện cho một cơ hội để duy trì hoặc

tăng quy mô đàn, để cải thiện đàn về mặt di truyền, hoặc

để cải thiện lợi nhuận kinh tế cho trang trại

Mục tiêu của việc nuôi bê con sơ sinh đến tuổi cai sữa là tối ưu hóa sự tăng trưởng và

giảm thiểu các vấn đề về sức khỏe

Trong video này, chúng ta sẽ thảo luận về sự phát triển tiêu hóa của bê con

hệ thống, tìm hiểu tầm quan trọng của sữa non đối với

hệ thống miễn dịch và các chất dinh dưỡng mà bê con cần để khỏe mạnh và phát triển tốt

Từ khi sinh ra đến khoảng hai tuần tuổi, bê con là dạ dày đơn, hoặc

một động vật dạ dày đơn giản

Bào tử là ngăn dạ dày duy nhất tham gia tích cực vào

tiêu hóa, và sữa hoặc chất thay thế sữa cung cấp các chất dinh dưỡng chính cho bê

Đầu tiên chúng ta hãy làm quen với giải phẫu của con bê

Luc sinh thanh,

dạ dày của bê có bốn ngăn giống như ở động vật nhai lại trưởng thành

Tuy nhiên, lưới của bê, dạ cỏ và omasum không hoạt động và không phát triển

Chức năng dạ dày của trẻ sơ sinh, abomasum tương tự như dạ dày của con người

Mục tiêu của chế độ dinh dưỡng cho bê là thúc đẩy sự phát triển dạ cỏ sớm trong cuộc sống để

để bê trở nên hiệu quả trong việc hấp thụ các chất dinh dưỡng và

có một quá trình chuyển đổi suôn sẻ hơn khi cai sữa

Vì vậy, hãy bắt đầu từ đầu cuộc đời của con bê, và

nói về cách con bê có thể tiêu hóa các chất dinh dưỡng, chẳng hạn như những chất có trong sữa

Khi mới sinh, dạ cỏ có ít mô phát triển và

thiếu một quần thể vi sinh vật

Bê con phụ thuộc chủ yếu vào men tiêu hóa của nó,

được giải phóng chủ yếu từ dạ dày và ruột non,

giúp giảm chất béo, carbohydrate không chất xơ và protein

Ở bê non, một số chất lỏng có thể đi qua dạ cỏ, và

chảy trực tiếp đến khối u qua rãnh thực quản

Bê ban đầu được bú sữa non,

sữa mẹ đầu tiên sau khi đẻ, trong khoảng ba ngày sau khi sinh

Trong vòng mười phút, một chất lỏng hình thành cục máu đông trong abomasum do các enzym

và

axit clohiđric tác dụng với casein và chất béo trong sữa

Sự đông kết liên kết nhiều casein và chất béo thành một cục, hoặc sữa đông,

để được tiêu hóa chậm bởi các enzym dạ dày trong khoảng thời gian từ 12 đến 18 giờ

Sự phát triển sữa đông cho phép bê ăn bữa ăn hạn chế,

so với các loài ương liên tục khác

Phần sữa không tạo thành khối đông được gọi là váng sữa

Whey bao gồm nước, khoáng chất, lactose,

và các protein khác, cụ thể là các globulin miễn dịch

Whey đi trực tiếp vào ruột non để

hấp thụ và / hoặc tiêu hóa trong vòng mười phút sau khi cho ăn

Từ ruột non,

các globulin miễn dịch có thể được hấp thụ vào máu của bê

Chúng ta sẽ thảo luận về tầm quan trọng của các globulin miễn dịch đối với

con bê chi tiết hơn sau

Lớp lót của thành dạ cỏ ở bò trưởng thành

có lớp nhú bao phủ rất rõ rệt

Những nhú này là những hình chiếu giống như ngón tay tăng lên rất nhiều

diện tích bề mặt dạ cỏ, khu vực mà chất dinh dưỡng có thể được hấp thụ

Trong vòng vài ngày sau khi sinh, dạ cỏ của bê con trở thành nơi chứa các vi khuẩn từ

thức ăn, môi trường ở bò

Sự phát triển nhú được kích thích bởi các sản phẩm cuối cùng của

lên men vi sinh vật

Cụ thể là axit butyric và ở mức độ thấp hơn là axit propionic

Có hai thành phần riêng biệt để phát triển dạ cỏ

Đầu tiên là kích thước vật lý của cơ quan

Đến bốn tuần tuổi, nếu bê con chỉ bú sữa, hoặc

sữa thay thế, dạ cỏ sẽ khá nhỏ

Khi sữa, hoặc chất thay thế sữa, được cho ăn với số lượng ngày càng tăng, abomasum phát triển trong

kích thước, nhưng dạ cỏ vẫn nhỏ theo tỷ lệ và chỉ phát triển vừa phải

Bê được cho ăn một lượng lớn thức ăn lỏng càng lâu,

hạn chế tăng trưởng của dạ cỏ so với kích thước của bê càng lớn

Sự kém phát triển của dạ cỏ làm giảm tốc độ tăng trưởng sau cai sữa

Khía cạnh thứ hai của sự phát triển dạ cỏ là sự kéo dài

của những nhú dạ cỏ và sự dày lên của các bức tường dạ cỏ

Quản lý cho ăn có thể ảnh hưởng đáng kể đến sự phát triển của chúng

Một con bê ăn ngũ cốc, ngoài sữa, cho thấy nhiều nhú hơn

phát triển và thành dạ cỏ dày hơn, sẫm màu hơn và nhiều mạch hơn

Bây giờ, hãy so sánh một con bê thứ ba bú sữa và cỏ khô chất lượng tốt từ ba ngày tuổi

Mặc dù ăn một lượng cỏ khô vừa phải,

các mầm nhú hoàn toàn không phát triển và thành dạ cỏ khá mỏng

Điều này là do các sản phẩm cuối cùng của quá trình tiêu hóa cỏ khô bao gồm nhiều axit axetic hơn,

mà thành dạ cỏ không sử dụng cho sự sinh trưởng và phát triển của nhú

Bê được tiếp cận với lượng lớn thức ăn thô sẽ có

sự gia tăng đáng kể về kích thước dạ cỏ

Tuy nhiên, điều này phần lớn là do kéo căng,

không thực sự phát triển của mô dạ cỏ

Cho bê con bú đúng lượng sữa non chất lượng cao

ngay sau khi sinh, đóng vai trò quan trọng đối với sức khỏe của bê con

Sữa non, được định nghĩa là sữa được lấy ra từ tuyến vú trong

24 giờ đầu tiên sau khi sinh, chứa các globulin miễn dịch,

khi được hấp thụ bởi ruột của bê, giúp bê chống lại các thách thức bệnh tật

Bê nhận đủ lượng và chất lượng sữa non,

phát triển tốt hơn và khỏe mạnh hơn nhiều

Các globulin miễn dịch được tìm thấy trong sữa non là các protein lớn

Bê có các lỗ mở trong ruột non để chứa protein

hấp thụ, nhưng những lỗ này đóng lại ngay sau khi sinh

Ba loại globulin miễn dịch có thể được tìm thấy trong sữa non

Immunoglobulin G chiếm 70 đến 80% các globulin miễn dịch,

và giúp xác định và tiêu diệt mầm bệnh xâm nhập

Immunoglobulin M bao gồm 10 đến 15% các globulin miễn dịch, và đóng vai trò là tuyến phòng thủ đầu tiên chống lại nhiễm trùng

Và cuối cùng, immunoglobulin A bao gồm 15% còn lại

immunoglobulin trong sữa non, và bảo vệ bề mặt niêm mạc,

chẳng hạn như ruột, khỏi vi khuẩn gây bệnh xâm nhập

Sữa non cũng chứa các vitamin, khoáng chất, năng lượng và

protein cần thiết cho quá trình trao đổi chất, tăng trưởng của bê và kích thích bổ sung hệ thống miễn dịch của bê

Để đảm bảo rằng con bê được miễn nhiễm từ đập,

Việc quản lý sữa non cần tập trung vào 3 yếu tố ngay sau khi sinh Sữa non bao lâu, bao nhiêu và chất lượng

Nên cho trẻ bú sữa non trong vòng một giờ sau khi sinh

Khoảng 35% các globulin miễn dịch ăn vào có thể được hấp thụ khi

bê con được bú sữa non ngay sau khi sinh

Nhưng điều này giảm xuống dưới 5% sự hấp thụ

immunoglobulin khi bê được cho ăn 20 giờ sau khi sinh

Cho ăn sữa non với tỷ lệ 12 đến 15% trọng lượng cơ thể bê con

Bê giống lớn, chẳng hạn như Holsteins nặng hơn 90 pound khi mới sinh,

có thể được cho ăn bốn lít khi mới sinh

Cho bê có trọng lượng từ 50 đến 90 pound ăn,

chẳng hạn như Jerseys, ba lít khi mới sinh

Nếu có thể, hãy cho tất cả bê con ăn thêm 2 lít sau khi sinh 12 giờ Không cho bê con bú đập để lấy sữa non

Mặc dù, bú sữa mẹ giúp tăng cường hấp thu,

nghiên cứu đã chứng minh rằng 25 đến 40% bê còn lại với đập

sẽ không ăn đủ sữa non để đạt được mức độ miễn dịch thụ động đầy đủ

Sử dụng sữa non chất lượng cao

Sữa non nên có hơn 50 gam mỗi lít globulin miễn dịch,

điều này tương đương với số đọc màu xanh lục trên máy đo màu

Máy đo khối lượng riêng của sữa non trước khi cho trẻ bú

Chất lượng của sữa non được quyết định bởi số lượng

Nếu một con bò tạo ra hơn 18 pound sữa non,

tỷ lệ thấp hơn 50% rằng nó sẽ chứa đủ các globulin miễn dịch

Độ dài thời kỳ khô

Nếu bò có thời gian cạn sữa dưới 45 ngày, thường có chất lượng sữa non kém,

cũng như những động vật có chế độ dinh dưỡng kém hoặc

stress nhiệt trong thời kỳ khô hạn

Con giống

Holstein có chất lượng sữa non kém hơn các giống khác

Sữa non từ Holstein thường có lượng immunoglobulin thấp hơn sữa non

từ bò Jersey

Và sau đó, tuổi của con bò

Những con bò cái già hơn có xu hướng có nhiều globulin miễn dịch hơn so với những con bò cái con đầu tiên,

vì chúng đã tiếp xúc với nhiều mầm bệnh hơn

Dinh dưỡng và quản lý bê, Phần 2

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Bản ghi tương tác - Bật chế độ bản ghi cơ bản bằng cách nhấn phím thoát

Bạn có thể điều hướng qua bảng điểm bằng cách sử dụng tab Để lưu ghi chú cho một phần văn bản, hãy nhấn CTRL + S Để mở rộng lựa chọn của mình, bạn có thể sử dụng CTRL + phím mũi tên Bạn có thể hợp đồng lựa chọn của mình bằng cách sử dụng shift + CTRL + phím mũi tên Đối với trình đọc màn hình không tương thích với việc sử dụng các phím mũi tên cho phím tắt, bạn có thể thay thế chúng bằng các phím HJKL Một số trình đọc màn hình có thể yêu cầu sử dụng CTRL kết hợp với phím alt

Sau vài ngày bú sữa non,

có một số tùy chọn cho ăn lỏng có sẵn

Chúng bao gồm sữa nguyên chất, sữa thay thế, sữa thải và

sữa non tươi hoặc sữa non lên men

Bất kỳ nguồn nào trong số này đều là nguồn cấp dữ liệu tuyệt vời khi có sẵn và

nếu nó phù hợp với chương trình nuôi bê

Sữa nguyên kem có thể là thức ăn lỏng chính cho bê, nghé, nếu đó là sữa nguyên chất khô

sẽ chứa 29 đến 30% chất béo, 25 đến 26% protein

Sữa nguyên kem sẽ cung cấp lượng protein và năng lượng dồi dào cho bê,

nếu một đến hai pound được cho ăn cho mỗi mười đến mười hai pound trọng lượng cơ thể Tuy nhiên, do thành phần của nó,

sữa nguyên kem có thể thiếu khoáng vi lượng và vitamin

Điều này có thể được khắc phục bằng cách cho bê ăn khởi động chất lượng

ngoài việc cho ăn lỏng

Có rất nhiều nơi vắt sữa tuyệt vời dành cho bê con

Mức protein trong các chất thay thế sữa thường dao động từ 18 đến 22 phần trăm

Các công thức mới được thiết kế cho

các chương trình cho ăn chuyên sâu chứa 28 đến 30 phần trăm protein

Các nguồn năng lượng chính trong sữa thay thế là lactose và chất béo

Lactose là nguồn cung cấp carbohydrate tốt nhất, và

Các chất thay thế sữa thường chứa 40 đến 50% lactose

Các nguồn chất béo trong chất thay thế sữa bao gồm mỡ lợn, mỡ động vật,

mỡ ổn định, và dầu thực vật hydro hóa

Hàm lượng chất béo cao hơn trong chất thay thế sữa có thể làm giảm tỷ lệ váng sữa Mức độ chất béo thay đổi từ 10 đến 22 phần trăm trong các chất thay thế sữa và nói chung Vậy sữa thay thế với 20% chất béo làm gì?

Thông tin bổ sung về các phương pháp nuôi dưỡng bê, chất lượng và bảo quản sữa non và Các lựa chọn cho ăn lỏng có thể được tìm thấy trong tài liệu đọc cho bài giảng này

Người quản lý bê nên giới thiệu thức ăn khô và

truyền nước cho bê trong vòng 3 đến 4 ngày sau khi sinh

Cho ăn một con bê thương phẩm mới bắt đầu hoặc một con hỗn hợp trong trang trại, kích thích chức năng và sự phát triển sớm của dạ cỏ, cho phép cai sữa sớm hơn,

và bổ sung dinh dưỡng do chương trình cho ăn lỏng cung cấp

Hai món khai vị chứa từ 18 đến 20% protein thực phẩm

Và khi chọn một con bê khởi động, hãy xem xét những điều sau

Hình thức vật lý chọn toàn bộ cuộn nghiền thô đã được nghiền thô, hấp hoặc

hạt kết cấu mảnh