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Milk composition and production are the interaction of many elements within the cow and her external environment. Composition of milk influenced by many factors such as genetic and breeds differences, stage of location, milking interval, seasonal variation, disease and nutrition. Nutrition is the major factor on both milk yield and composition. The three factors: Genetic makeup, nutrition and management decide the productivity of dairy cows. Improvement of genetic make up only contributes up to 30% to production, while the 70% is dependent on nutrition and management. Unfortunately, indigenous of tropical dairies are low milk producers because of the shortage of nutrition. Poor nutritive values of feeds lower the production capacity and fertility potential of dairies. If fed well, with supplementary feeds and under good management, more milk could be produced from them. So, supplementary feed with optimum dietary ration providing for dairy cows in good management improves the production level and good proportional composition of product with high nutritive value.
From agricultural activities, dairy production and its management is the one which is the interest of every country because of high nutritional value of milk and milk products and another purpose gained from them. And the feed they consume is not compete with human food and also, they convert feed which is not directly eaten by human being to products that human being can consume. That means, special ability of dairy cattle to transfer feed stuffs into edible food for humans and as much as 70% of their total feed intake is from non-human food. Food requirements of rapidly expanding human population is the other reason which initiates or give importance the development of dairy production
Milk composition and production are the interaction of many elements within the cow and her external environments Chemical composition of milk is variable and influenced by intrinsic factors like genetic and breed differences, stage of lactation, milking interval, seasonal variation, disease and nutrition. Protein content of milk is positively correlated within a population of dairy cattle; however, different breeds of cattle vary in average component levels. Holsteins have the lowest fat and protein content, while Jersey and Guernsey breeds have the highest. Because Holsteins
produce more milk, they generally have a higher total yield
of fat and protein than other breeds. There are many factors that can affect milk fat and protein, and many of them can be manipulated to enable you to achieve higher than average levels of milk components. Keep in mind that herds that are below breed average will have more opportunity to improve component levels. Herds that are already above average may have better success by focusing on increasing milk yield, which will increase the total amount of fat and protein production .
Stage of lactation affects milk protein and fat percentages very similarly. The highest amount of protein and fat in milk is found just after freshening, in colostrum. Levels drop to their lowest point between 25 and 50 days after calving and peak at 250 days as milk production begins to decrease. Age tends to cause both milk fat and protein to decline as the animal becomes older. Milk fat falls about 0.2% each year from the first to fifth lactation likely as a result of higher production and more udder infections. Protein decreases 0.02 to 0.05% each lactation as animals age.
Season dramatically affects milk fat and protein. The hot, humid months depress fat and protein content. There is a gradual increase of protein and fat in milk through the fall and peak levels occur in the colder months of winter. As temperatures increase through the spring, component levels are gradually decreased.
These changes may be indicative of feed intake patterns, which
are lower in summer due to changes in weather and temperature.
Mastitis infections reduce fat and casein but increase blood protein
content of milk. Of all the factors affecting milk composition,
nutrition and feeding practices are most likely to cause problems;
however, management changes made here are able to quickly
and dramatically alter production of fat and protein other than
genetics. Digestion of fiber in the rumen produces the volatile
fatty acids (VFAs) acetate and butyrate. Butyrate provides energy
for the rumen wall, and much of it is converted to betahydroxy
butyrate in the rumen wall tissue. About half of the fat in milk is
synthesized in the udder from acetate and betahydroxy butyrate.
The other half of milk fat is transported from the pool of fatty
acids circulating in the blood. These can originate from body fat
mobilization, absorption from the diet, or from fats metabolized in
the liver. Rumen microbes convert dietary protein into microbial
protein, which is a primary source of essential amino acids for
the cow. These amino acids are used by the mammary gland to
synthesize milk proteins
Glucose is required to provide energy to support this protein
synthesis. Glucose is either formed from the VFA propionate
in the liver or absorbed directly from the small intestine. If too
little propionate is absorbed from the rumen, the cow will have to
breakdown amino acids and convert them to glucose (a process
called gluconeogenesis); this can reduce the supply of amino
acids available to make milk protein. In addition, some albumin
and immunoglobulin protein are transferred directly to milk from
the blood. The relative amounts of protein and energy that are
available in the rumen at a given time is the major factor affecting
rumen fermentation and therefore milk components. Any diet or
management factors that affect rumen fermentation can change
milk fat and protein levels. Consistently providing adequate
energy and protein and balanced amounts of rapidly fermentable
carbohydrate and effective fiber are keys to maintaining optimum
levels of milk components.
The challenge in feeding for milk components is that high
energy, low fiber diets that increase milk protein are likely to
reduce fat levels. This may also be the case in some diets with
rumen modifiers, such as Rumensin®; however, this product has
other ways to affect the rumen that do not necessarily alter milk
components. Any situation that causes cows to eat abnormally or
limits feed intake may affect milk components. Examples include:
overcrowding at feed bunks, housing heifers with older cows in
facilities at or near full capacity, feeding rations that encourage
sorting, feeding infrequently in a conventional system (non- TMR),
failing to push feed up or feed TMR often enough, feeding protein
feeds before energy feeds and feeding grain before forage in non-
TMR systems. These conditions can create slug feeding (one or
two meals per day versus 10 to 15) or allow cows to eat high grain
meals part of the time and high forage meals the remainder of the
day. Ensure that fresh feed is available 20 hours each day, spoiled
feed is removed from bunks, and shade or cooling is provided
during hot weather to help maintain normal intake and normal
meal patterns. Poor ventilation or cow comfort also can depress
milk fat and protein production by reducing intake. Finally, make
ration changes gradually to allow rumen microorganisms time to
Any reduction in rumen microbial protein production from
nutrition or feeding management imbalances will reduce milk
protein by way of less microbial protein for the cow to digest
and depress fat by limiting VFA production in the rumen. Proper
body condition is essential so that high producing cows can draw
on body stores of nutrients to support milk production. If body
stores are minimal, yields of milk and milk components will
suffer. On the other hand, excessive body condition increases the
risk of metabolic problems and calving difficulty. Weight loss in
early lactation can increase milk fat content for a short period
of time. Both thin and fat cows tend to have low milk fat in later
lactation. Protein can be depressed at calving if animals are overly
obese or underweight. In addition, some research shows that
underfeeding protein during the last three weeks before calving
can depress milk protein . In general, as energy intake or ration
energy density increase and/or fiber decreases, milk fat content
will be reduced, while protein is increased. In contrast, as ration
fiber levels increase and/or energy is reduced, milk protein is
depressed, and milk fat is increased. Lack of energy intake or
lower ration digestibility may reduce milk protein by 0.1 to 0.4%.
This reduction may result from underfeeding concentrates, low
forage intake, poor quality forage, and failure to balance the ration
for protein and minerals, or inadequately ground or prepared
grains. Shifting rumen fermentation so that more propionic acid is
produced is apt to increase milk protein and decrease fat content.
However, excessive energy intake, such as overfeeding concentrate,
may reduce milk fat content and increase milk protein. Normal
protein levels can be expected when energy needs are being met
for most of the cows. Often this is impossible to achieve with high
A deficiency of crude protein in the ration may depress protein
in milk; marginal deficiency could result in a reduction of 0.0 to
0.2%, while more severe restriction of diet crude protein would
have greater impact. However, feeding excessive dietary protein
does not increase milk protein, as most of the excess is excreted.
Dietary protein has little effect on milk fat levels within normal
ranges. Diet protein type also could affect milk protein levels. Use
of non-protein nitrogen (NPN) compounds, like urea, as protein
substitutes will reduce protein in milk by 0.1 to 0.3% if the NPN is
a main provider of crude protein equivalent. Rations higher than
recommended in soluble protein may lower milk protein by 0.1
to 0.2 points. NPN levels in milk will be increased by excessive
protein or NPN intake, heavy feeding of ensiled forages, ensiled
grains, immature pasture and lack of rumen undegradable protein
in the diet. Balance rations for crude protein, rumen undegradable
protein, rumen degradable protein, and soluble protein. For high
producing cows, balancing for amino acids also may be required.
An increase in the intake of concentrates causes a decrease
in fiber digestion and acetic acid production. This creates an
increase of propionic acid production. Propionic acid production
encourages a fattening metabolism that is in opposition to milk fat.
Addition of buffers to some rations may help to prevent acidosis;
this will not change milk protein but will increase milk fat content
. Animals that eat a substantial amount of concentrates or a low
ratio of dietary forage to concentrate may develop acidosis even
when buffers are added to the ration. The non-fiber carbohydrate
(NFC) portion of the diet is highly digestible and can influence
both fat and protein in milk. Excessive amounts of NFC can depress
fiber digestibility, which reduces the production of acetate and
leads to low milk fat (1% or more reduction). At the same time,
greater propionate production allows higher milk protein levels
of 0.2 to 0.3%. Generally, an NFC of 32 to 38% of ration dry matter
is recommended to optimize production of milk fat and protein.
Balance rations for lactating cows to contain at least 40 to 45%
of ration dry matter from forage. This may be altered by the level
of corn silage in the ration and the level of high-fiber by-product
feeds in the ration. Low forage intake can cause a major reduction
in the fat content of milk due to low fiber levels. Several potential
reasons for low forage intake are inadequate forage feeding, poor
quality forage, and low neutral detergent fiber (NDF) content
in forage that was cut too young or late in the fall. Although low
forage (high energy) diets increase milk protein production, this
strategy is not recommended. The low forage levels contribute to
acidosis and laminitis; they do not promote good health for the
rumen or the cow in the long run. Protein and fat content also can
be changed due to the physical form of forage being fed. Much of
this is related to ration sorting and failure to provide a consistent
diet throughout the day. Coarsely chopped silage and dry hay are
the most common causes of sorting. At the other extreme, very
finely ground diets negatively affect rumen metabolism and
depress fat and protein production. Monitor ration particle size to
ensure that adequate effective fiber is provided, TMRs are mixed
properly, rations are distributed evenly to all cows, and sorting is
Adding fat to the ration can affect milk component levels
depending on the amount and source of fat. Fat is generally toxic
to rumen microbes and may reduce fiber digestibility when fat
from natural sources exceeds 5% of ration dry matter. If rumen
inert or bypass fat is used, total fat content may safely reach 6 to
7%. At low levels of dietary fat, milk fat content could increase
slightly or show no change at all. Milk fat is reduced at higher
levels, especially with polyunsaturated oils. If fat or oil is rancid,
milk fat content decreases even at low levels of consumption.
Milk protein content may be decreased by 0.1 to 0.3% in high-fat
diets. Generally, the objective is reviewing the significance of feed
supplementation on milk yield and milk composition of dairy cow
The period following milk removal is characterized by low
intra-alveolar pressure, which facilitate the transport of newly
synthesized milk into the alveolar lumen. As secretion continues
between milking’s, pressure is exerted on the secretory process by
the alveolar luminal contents. When the luminal pressure exceeds
the force of secretion as the alveolar enlargement reaches its limit.
It is presumed that the distention pressure of the lumen exceeds
the strength of the secretory mechanism needed to push the newly
forced milk precursors by chemical feedback mechanism and or
physical factors (e.g.,intra-mammary pressure .
The physical factors are a result of the distended alveoli
partially displacing all other intra-mammary compartments,
including the blood vessels. With restricted blood flow, less
nutrients are available for milk production, less hormones are
available to drive the mammary synthetic systems, removal
of waste products of synthesis is reduced and less ox toxin is
available to stimulate the myoepithelial cells. In dairy cows,
average secretion rate begins to decline after ten hrs since the
last milking and secretion stops after thirty five hrs .The pressure
measured in the teat cistern increases in three phases. An initial
rapid increase in the pressure caused by the movement of residual
milk into the cistern from the alveoli and small ducts. The second,
lower phase can be an accumulation of newly synthesized milk
that is released into the duct system from the alveolar lumens as
they begin to accumulate milk. The third phase is marked by the
accelerated pressure increase and probably represent over filling
of alveoli, ducts and gland cisterns .
Milk composition and production are the interaction of many
elements within the cow and her external environments . High
milk yield of satisfactory composition is the most important factor
ensuring high economic returns. If the composition of milk varies
widely, its implication is that nutritive value and its availability
as a raw material will also vary. Chemical composition of milk is
variable and influenced by intrinsic factors like genetic and breed
differences, stage of lactation, milking interval, seasonal variation,
disease and nutrition .
Genetic and breed differences: Heritability is defined
as the ratio of genetic variance to total phenotypic ratio. The
concentrations % of the three major milk constituents are
genetically controlled to a considerable extent. Heritability’s
of fat, protein, and lactose contents average: 0.58, 0.49 and 0.5
respectively, while that of milk yield average is 0.27 . The above
Table1 indicate that there is a room to increase milk protein % by
genetic selection without increasing fat % and that selection for
high milk yield alone may reduce milk fat and protein %. Milk from
Holstein cows has a lower milk fat % than milk from Jersey and
Guernsey. droplets also differ among breeds. Holstein has smallest
fat droplet while Guernsey and Jersey Brown swiss has the largest.
Milk of Jersey cows also has a higher total solid than milk from
other dairy cattle breeds. Differences in milk composition among
individual with a breed are often larger than differences among
breeds. Milk color also affected by breed type. For example, milk
from Guernsey and Jersey is yellowish in color because if these breeds convert much less carotene (yellow pigment) to vitamin A
than other breeds of dairy cow (Table 2).
Stage of lactation: Colostrum, the first mammary secretion
after parturition differs greatly from normal milk. Cows colostrum
contains more minerals, protein and less lactose than milk. Fat
is usually higher in colostrum than in milk.Ca,Mg,P,and Cl are
high in colostrum’s, whereas K is low. Fe is 10-17 times higher
in colostrums than in milk. The high levels Fe are needed for the
rapid increase in hemoglobin in the red blood cells of newborn
calf. Colostrum contains ten times as much vitamin A and three
times as much vitamin D as milk . The most remarkable
differences between colostrum and milk is the extremely high
levels of Ig content of colostrum. Mammary secretion gradually
changes from colostrum to normal milk within 3-5 postpartum
. From normal milk changes in composition occur during the
first few days continue but at reduced rate for about five weeks
of lactation. Fat and protein then rise gradually and may increase
mare sharply near the end of lactation. Lactose decreases while
mineral concentration increases slightly during that period.
Milking Interval: When milking is done at longer intervals
the yield is also more with a corresponding smaller percentage of
fat, whereas milk drawn at short intervals yield smaller quantities
with higher amount of fat. The effect milking interval is mainly on
fat percentage rather than the SNF . The fat content of milk is
usually lower in the morning than in the evening milking, because
there is usually a much shortage interval between the morning and
evening milking than between evening and morning. SNF content
varies little even if the intervals between milking vary. Cows are
usually milked at equal intervals (12-hrs interval for two times
milking). Cows milked at unequal intervals produce less milk than
those milked at equal intervals. The reduction in milk yield is more
i8n high producing cows than in low producing ones. In complete
milking for several consecutive days can permanently reduce milk
yield for the entire lactation. Milking time for most cows is 5-6
minutes per cow .
Season of calving and seasonal variation: The effect of
season of calving on milk yield is confounded by breed, the stage
of lactation and climatic condition. Cows calving in the late fall
to soring produce more milk (up to 8% more) than cows calving
in the summery. This is likely due to an interaction between
day light and ambient temperature in case of tropical areas.
Seasonal differences have become less significant because of
better feeding and management of dairy cow can overcome this
effect. The seasonal variations in milk composition are commonly
observed with dairy cattle in temperate regions. Milk fat and
SNF percentages are highest in Winter and lowest in Summer.
Milk fat and protein percentages are lower by 0.2-0.4 in summer
than in winter. The effect of ambient temperature on milk yield is
dependent up on the breed, for example, Holstein and the other
larger breeds are more tolerant to lower temperature whereas the
smaller breeds particularly the Jersey and Zebu are more tolerant
to high temperature. Milk production declines when environment
temperature exceeds 27 degree Celsius. The reduction in milk yield
is largely due to drop in feed intake. High temperature affect high
producing cows more than low producers and it is particularly
harmful during the peak of lactation.
Disease: The main disease affect milk yield and milk
composition of dairy cows is mastitis. It impairs the ability of
secretory tissue synthesize milk composition and destroys the
secretory tissues and consequently lowering milk yield. A decrease
in milk production persists after the disappearance of the clinical
signs of mastitis due to a destruction in the secretory tissues .
Infection of udder (mastitis) greatly influences milk composition.
Concentration of fat, SNF, lactose, casein, beta-lacto globulin and
alfa-lactalbumin are lowered and concentrations of blood of blood
serum albumin, Igs, sodium, chloride are increased . In severe
mastitis, the casein content may be below the normal limit of 78
% of total protein and chloride content may be rise above the
normal maximum level of 0.12 %. Mastitis is also responsible for
differences observed in milk composition from different quarters
of the udder
Nutrition: Nutrition has also a major effect on both milk yield
milk composition. According to O’Connor , under feeding
reduces the amount milk production, the fat, protein and SNF,
contents of milk. As a general rule it is believed in that any ration
of diet that increases milk production, usually reduces the fat
percentage of milk and fat content is influenced more by roughages
(fiber) intake and SNF content can fall if the cow fed a low energy
diet, but it is not greatly influenced by protein deficiency, unless
the deficiency is acute. Of all milk components, milk fat is the most
influenced by dietary manipulations. Most of changes in milk
composition due to dietary manipulation are related to changes
in ruminal acetate: propionate ratio. Several nutrition factors
can influence milk composition. These includes plan of nutrition, forage concentrate ratio, forage quality (e.g., particle size), level and
type of dietary fat. In plan of nutrition, under feeding dairy cows
reduces lactose percentage and increases fat percentage. Feeding
imbalance rations (e.g., low energy: protein ratio) may reduce milk
fat and protein percentages. In case of forage concentrate, as the
proportion of the concentrate in the ratio increases (above 50-60
% of ration), milk fat % tends decline. This is mainly because of the
lower ruminal production of acetate and butyrate (precursors of
milk fatty acid synthesis in the mammary gland) associated with
feeding high concentrate diets. The extent of milk fat depression is
influenced by other feeding practices such as frequency of feeding
and feeding system. Feeding cows less frequently especially if
the concentrates are fed separately from the forage results in a
reduced ruminal acetate: propionate ratio which in turn can result
in reduced milk fat % will be less where total mix rations are fed
and or if feed is offered three or more times daily
Forage particle size (forage processing), feeding finely
chopped forages has a negative impact on milk fat % and may
cause milk fat depression syndrome (drop of milk fat % below 3
%). Cows fed finely chopped forages spend less time to chewing
and therefore, will produce less saliva. Ruminal PH will drop as less
saliva is produced to buffer the acid production in the rumen. As
the ruminal PH drops below 6, the activity of cellulolytic bacteria
is reduced and so it is the production of acetic acid and butyric
acid (precursors of short chain fatty acid synthesis in mammary
gland). In case of level of starch in the ration, as the level of starch
in the ration increases, the level of acetate produced in the rumen
is decreased while that of propionate is increased. This may cause
a reduction in milk fat %. Dietary Fat Corporation or oil in dairy
cow ration can substantially alter the profile of milk fatty acids.
The effect of supplemented fat in milk fat % depends on the type
of supplement of fat. Feeding poly unsaturated fat (susceptible bio
hydrogenation in the rumen) such as vegetable oils may reduce
milk fat % whereas feeding protected fat tend to increase milk
fat %. Changes in dietary protein levels have minimum effects on
milk fat content. When the protein content of the diet is limiting,
increased dietary protein may increase milk fat content through
increases in roughage intake (Table 3).
Feed serves many different purposes, including the following
Maintenance: The normal activities of staying alive breathing,
blood circulation, digestive process, etc. all requires nutrient. This
maintenance is not for extra function like production unless extra
feed is provided for cell function .
Reproduction: Pregnancy and delivery make demands on the
dam which have to be met from her feed, if it is not to lose weight.
The fetus increases in size quickly during the last two to three
months of gestation, drawing on the body reserves of the dam.
Lactation: Producing milk either for one or two offspring or
for human consumption requires high levels of energy and protein
and good access to protein and good access to water.
Nutritional requirement of dairy cow influenced by many
factors like stage of production, condition of the environment, size
of the cow and the like.
Stage of production: One of the most challenging aspects of
dairy cow nutrition is that their requirements change during the
course of a year based on stage of pregnancy and lactation NRC
Weather: Cold weather greatly increases the nutritional
requirement. Therefore, during cold weather, the cow’s diet may
need to be supplemented to allow for the additional requirement
dairy perform optimally in their “their monaural zone” where
temperatures are either too hot or too cold. When the ambient
temperature, which includes wind, humidity, solar radiation and
air temperature, is outside of that zone, dairy performance is
depressed . The most common situation dairy man face is an
ambient temperature below the lower critical temperature or the
lower range of the thermo neutral zone. Tit should be pointed out
that in cases simply feeding more of a low-quality feed stuff will
not meet these additional requirements, in which case the energy
density of the diet must be increased by either feeding a highquality
forage or by adding a high energy supplement.
Size: As cows size increases, the nutritional requirement for
energy and protein increases. This should be expected because
the larger cow is the more energy and protein it takes to maintain
normal body functions.
The feed value of forage that form the basis for ruminant
feeding is a functional of its nutrient content and digestibility,
its palatability (which determines its consumption level) and
the associative effects of the other feeds . Interplay of these
factors determines the effective utilization or feed value of the
material. Strategies for ensuring adequate nutrition of animal
includes the following like: matching dairy production system to
available resources, selection of crops and cropping systems that
will maximize biomass production, and developing the simple
techniques to optimize the use of different components of crops
for different end purpose, making more efficient and wide spread
use of agricultural and industrial by products as source of dairy
feed, and also conserving feeds when it is available for drought
season. From these strategies, increasing feed availability with
production system of dairy number is through increasing off take
of animals through sale (destocking). The amount of feed available
to the remaining animals will increase in the process  (Table
Supplementary feed is any stuff added to the total diet of
the animal to increase the nutritive value of the feed and to
increase content of single nutrient or compound nutrient. These
supplementary feeds includes protein supplement (legumes,
oil seed cause, meat meal, fish meal), mineral supplements (salt
(Na), limestone (ca), bone meal (ca and p), and others), vitamin
supplement (natural and synthetic) and energy supplement (fat
and carbohydrate like concentrate feed those the high amount
of energy and low fiber content and high digestibility with high
protein content .
Protein supplement: Conditions under which milk
production can be increased by feeding protein supplements are
well defined, although it is not possible to estimate liters of milk per kg of supplement with great accuracy. Results from feeding
trials in Australia indicate that milk responses from protein
supplements can be up to 1.5 liter per kg supplement than from
equal weights of cereal grains. Usually the responses are much
lower when energy is first limiting. In most cases milk production
from tropical pastures is limited primarily by energy. When energy
is limiting, protein supplements gives similar milk responses
equal amount of cereal grains and surplus nitrogen is converted
to ammonia and excreted as urea  However, as energy supply
from cereal grains is increased, the protein content of the diet
becomes limiting for milk production. Protein supplement then
allow increases in milk yield with only small changes in milk
composition. The conditions where protein supplements give
greater milk responses than cereal grains are determined by stage
of lactation, Genetic potential, forage quality degradability of the
protein supplement, substitution rate.
Energy supplement: In order to improve milk production
levels, energy input such as concentrate feeds have to be considered
essential for any enterprise, even for those based on dual purpose
systems, since reduced intake of energy by dairy cows consuming
low quality forages is the principal cause of low milk production
.Traditionally, energy supplements are based on cereal grains that
include barley, sorghum, wheat, cats, maize, and etc, Molasses is
a very popular energy source for cattle grazing tropical pastures.
Agro- industrial by products are fed as supplement to roughagebased
diets, particularly in dairy production system for milking.
Concentrates rich in energy mixture or adulteration with other
depends on the quality of the basal roughage and the level of
production. Agro industrial by products can be utilized by mixing
of two or more of the ingredients to make concentrate at home or
using a single in gradient. They have special value in feeding cattle
mainly in urban and pre urban dairy production systems as well
as in situation where the productive potential of the animals is
relatively high ad require high nutrient supply. These by products
are rich in energy and protein contents or both, they have low fiber
content, high digestibility and energy values compared to with the
other class of feeds .To prevent the effect of heavy concentrate
feeding on low forage, concentrate ratios can be mitigated by
splitting up the concentrate allowance in to several smaller meals
spread more evenly over the twenty four hours. By this means,
digestive up sets are avoided, protein is more efficiently waltzed,
and lactation partition is more normal. Rig milk fat is improved
Mineral supplement: In providing proper nutrition to dairy
cows, the dairy man needs to consider minerals in addition to
protein, energy, water, and vitamins. Even through minerals
are needed only in small amounts, they are very important for
optimum reproduction, immune function, and optimal milk
production. Minerals are divided in to two groups by the amount
needed of each. Macro minerals are required in larger amounts,
while micro minerals are required in smaller amounts. The micro
minerals required includes calcium, phosphorus, magnesium,
potassium, sodium, chloride and sulfur. The micro minerals
required includes Iron, cobalt, copper, manganese, zinc, Iodine, and
selenium cows get some of the micro minerals and micro minerals
from the feeds they eat. However, minerals must be added to the
ration in order to meet the requirements, because, the forages
and grain do not provide adequate amounts. If these minerals are
not, supplemented, problems may occur. For instance, selenium
deficiency can cause retained placentas .
Several items must be taken into consideration when buying
mineral supplement. First, the supplement must contain all
the macro minerals and micro minerals that are deficient in
the ration. Also, the supplement must contain the appropriate
amounts of each mineral to be effective. The in gradients with
supply the semimetals should also be considered because some
a lower bio availability than others. Bio availability is the ability
of the cow to digest and utilize the minerals provided. If the bio
availability of the cow is low, then the amount of the mineral
fed must be increased, so the cow will get an adequate amount.
For example, copper oxide has very low bio availability. Copper
sulfate is a better source of copper . The best way to feed the
mineral supplement is by force feeding rather than free choice.
When minerals are supplemented free choice, the cow does
not eat to meet her mineral requirement needs. Force feeding
refers to mixing the mineral supplement with the grain mix or
the total mixed ration. This ensures that the cow gets enough of
each mineral to meet her requirements. It is equally important
not to just dump a lot of mineral supplement with the grain mix
or total mixed ration because too much of certain minerals will
cause toxicity problems or inhibit the functioning ability of other
minerals. Thus, the forages fed to the cows should first be analyzed
for their mineral content, if it is not already known. Next, the
ration should be balanced so that all of the mineral requirements
are met. Then the deficiency can be identified and corrected by
feeding the correct mineral supplement
Even though cows should be fed heavily with concentrates
in the first few weeks of lactation, to encourage high peak yield,
there are some specific problems, some of which are dealt with
more heavy concentrate feeding in early lactation. These includes
ailments such as ketosis, abomasal displacement, laminitis,
and mal partition syndrome involving low fat milk and reduced
lactation efficiency .
It is generally accepted that some processing of cereal grains
is required before cattle can effectively utilize the energy and
nutrient content of concentrate feeds. While increasing the degree
of processing improves utilization, it may also lead to digestive
problems when high levels of grain are fed and may accentuate
fat depression in milk. The type and extent of processing
required depends on number of factors including the grain type,
the proportion of grain in the diet, palatability, and the risk of
developing digestive problems. If a whole untreated grain is fed, large proportion of it can pass undigested in the faces. The
minimum level of processing required to ensure efficient grain
digestion is cracking the seed coat t expose the endosperm. This
must be achieved by mechanical or chemical treatments as dairy
cattle have only delimited ability to chew small cereal grains. The
main nutritional significance of the seed coat is the extent to which
it dilutes the amount of starch in the diet .
The second level of processing involves grinding and rolling,
to reduce particle size which in turn determines the surface
area, which is exposed to microbial and digestive enzymes. This
ultimately influences the number of starch granules freed from the
protein and no starch carbohydrate matrix of the endosperm .
When starch granules are tightly held with in endosperm matrix,
it may be necessary to use gelatinization and or hydration (i.e.
high temperature with or without water) to disrupt the granules.
Conversely, grinding or milling can produce extremely fine
particles which can be rapidly fermented digested and can reduce
the palatability of the grain if excessively dusty.
The third method of processing is steam flaking. With this
treatment, the whole grain is heated with steam for 10-40 minutes
and subsequently rolled to varying degree . This breaks the
seed coat and endosperm, although the whole grain remains as
one. This process gelatins much of the starch making it more
susceptible to enzymatic attack. Grains such as barley, whet and
oats, which have a naturally high fermentation and intestinal
digestion when ground or dry rolled, are not affected as much
by steam flaking rolled grain. At present time, practical problems
such as risks in handing NaoH as well as corrosion concerns
restrict use of this processing method. For this reason, alternatives
such as ammonia treatment might be more practical.
The fourth method is polluting which is common commercial
process where small particles are combined into large particle
by means of a mechanical process in combination with moisture,
heat and pressure. It is believed in that concentrate polluting
decrease waste, reduces dust, minimizes spoilage , improves
feed efficiency and provides a means for uniform distribution of
protein and minerals. There are several potential advantages of
feeding pellets over meal or a loose ix like Balanced proportion of
protein, minerals, vitamins, and buffers can be in corporate in to
the pellets, the higher the level of concentrate feeding, the greater
the live hood that nutrient balancing will be necessary , risk
of excessive un palatable and toxic substances associated with
supplements for example urea are avoided by careful blending
of ingredients, pellets usually are loss dusty than mechanically
processed grains. Therefore, it appears that relatively small
change in the processing of concentrate can have a substantial
influence on the degradation characteristics of the concentrate
and can alter the yield of milk components significantly. Polluted
for mutations, when compared to textured concentrates, tend to
improve degradability, lower rumen PH, increase milk and protein
yield and can depress milk fat yield and percentage, without
affecting intake [25-27].
Milk composition and production are the interaction of
many elements within the crow and her external environments.
Composition of milk influenced by many factors like genetic
and breed differences, stage location, milking interval, seasonal
variation, disease and nutrition from these factors, nutrition is
the major factor on both milk yield and milk composition. Under
feeding reduces the amount milk production, fat, protein and
SNF contents of milk. Of all milk components, milk fat is the most
influenced by dietary manipulations. Several nutritional factors
can influence milk composition. These includes: - plan of nutrition,
forage concentrate ratio, forage quality (like particle size, level and
type of dietary fat). Major components of milk are water lactose,
lipids, proteins, salts, minerals and vitamins. These components
arising from several factors including breed, individuality of the
animal, stage of location, health of the animal, (especially mastitis)
and nutritional status.
Dairy cows use nutrition for purpose of maintenance,
reproduction, location (production) and etc. while factors
influencing nutritional requirement of dairy cow are stage of
lactation, condition of the environment size of the cow and the
like. Strategies for ensuring adequate nutrition of dairy cows
are matching dairy production system to available resources,
selection of crops and cropping system that will maximize biomass
production, and developing the simple techniques to optimize
are use of different components of crops residues, making more
efficient and wide spread use of agricultural and industrial by
products as source of elating feed, conserving feeds when it is
available for drought seasons when saucily of feed is happen
and using grazing system for pastures for avoiding wastage of
resources. Supplementary feed is any feed stuff added to the total
died of the animal to increase the nutritive value of the feed and to
increase content of a single nutrient or compound nutrient. These
types of supplementary feeds are protein, energy supplement
(carbohydrate and fat), mineral, and vitamin. It is believed in that
some processing of supplementary feeds is required before cattle
can effectively utilize it. But, type and the extent of processing
depends on number of factors like supplementary feed type,
the proportion of supplementary diet, palatability and etc. the
methods and system of processing includes creaking, grinding,
steam flaking, polluting and etc
In tropical areas except commercial dairy farm, state farm,
and farms follow modern method of keeping dairy cattle, others
like farmers dairy cow fail under shortage of nutrition, poor
management, and the production and product obtained from these
dairy cows are less. This under feeding susceptible the dairies for
disease and lose of the animal also there. To reduce some extent
degree of these problems, the following activities should be done.
a. Supplementary feeds should be supplied.
b. Management should be considered as major activity of
c. Having more dairy cows without enough feed available
should be reduced to be profitable from optimum number of
head of dairies under good management.
d. Feeds should be conserved when it is available for the
period shortage of feed is occurring.
e. Ways of providing supplementary feeds should be
proper to avoid extra problem happen with in the cow of
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Jennifer (1998) Selection of mineral supplement for dairy cow.
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Clarence Hennery (2001) Research on milk and milk product Deondarza and Mary Beth. minerals North Dakota state university Fargo, p. 57.
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