2. Among dairy breeds, the intense selection for higher
milk production during the last 20 to 30 years has led
to a negative energy balance in early lactation.
Consequently as milk production increases,
reproduction efficiency decreases.
E.g. conception rate of 50% was considered poor
performance 20 years ago. Today, is above average in
the USA.
3. A major realistic goal of any breeder should be raise
or market 75-85 calves per 100 cows every year.
As pregnancy rate increases, the calving to
conception interval decreases, thereby increasing the
amount of milk produced per day of herd lifetime and
reducing the number of cows culled for reproductive
failure
Collectively, this increases herd income
5. Lactation VS Conception
The ability to conceive is influenced strongly by the
physiology status of the cow.
In mammals, milk is essential to survival of the
young. Thus in early lactation, the body gives milk
production the highest priority for the available
nutrients.
In addition to nutrients found in the diet, females in
early lactation tend to mobilize their body reserves to
support milk production.
Generally, a female cannot eat sufficient amounts
during early pregnancy.
6. They are in a state of negative energy balance. They
loose weight and their ability to conceive is drastically
reduced.
It’s only at a later stage of lactation, when the energy
ingested is in balance with the energy required for
milk production, that the ability to initiate a new
pregnancy increases.
Depending on the milk production in early lactation.
Negative energy balance may last for 2 to 10 weeks of
lactation.
7. Energy deficiency in early lactation cannot be avoided
but it should be minimized. In dairy herds where
cows loose excessive body weight during early
lactation and don’t show signs of estrus by 30-40 days
after calving, changes must be made in feeding
practices during early lactation, late lactation and dry
period.
8. Excessive intake during late lactation and dry period
can lead to “Fat cow” problems. cows that are too fat
have a higher incidence of difficult calving, retained
after birth, uterine infections and cystic ovaries. This
disorders are frequently secondary to disorders
associated with excess body reserves.
Rapid mobilization of fat results in accumulation of
fat in the liver. This causes the cow to loose appetite,
which further worsens their energy deficiency and
delays the return of normal estrus activity.
9. These problems will be minimized adjusting the
feeding of cows, starting in late lactation to avoid
under conditioning or over conditioning during the
dry period.
Feeding during the dry period should not be aimed at
altering the amount of body reserves but simply to
maintain the ideal body condition in the late
lactation.
10.
11. Body Condition
The goal is to have a cow that is neither too fat or too
thin in early lactation.
For every Kilogram lost, it’s enough to produce 7 Kgs
of milk.
12.
13.
14.
15.
16. • Body condition indicates how much stored energy a cow has
for future use. BCS can help you track energy balance and
understand production and reproductive performance.
• The most common body condition scoring system ranks cows
from one to five with a score of one being thin and a score of
five being obese.
Areas to evaluate when body condition scoring include hooks,
pins, tail head, and the ligaments around these bones.
• Body condition of feeding groups should be evaluated. It will
reflect the true energy content of the diet.
• Cows should be scored at calving during their first postpartum
exam, when bred, when checked for pregnancy, some time
during late lactation and at dry-off.
17. An evaluation of body condition can help you understand
the past nutritional status of your cows and why your milk
production and reproductive performance results are good
or bad.
It will also show you some of the challenges to come. Body
condition is an indication of how much energy a cow has
stored for future usage. Body condition scoring was
developed to help farmers and nutritionists more
definitively assess and track body condition. This is very
important because the monthly changes in body condition
tend to be more highly correlated with health,
productivity, and reproduction than a cow’s actual body
condition on any particular day.
18. BCS = 1.5
This cow is too thin and is hopefully rarely seen on a
farm. This cow will not milk well or reproduce. This cow
probably isn’t healthy. The vertebrae, short ribs, hooks,
pins, and tail head are very sharp and visible. One-half
of the length of the transverse processes is visible. The
ligaments are easily seen. The area around the tail head
and the dish of the rump (thurl) are very dished. There
are folds of skin seen between the tail head and pins.
19. BCS = 2
This cow is very thin, causing low milk production
and poor reproduction. Health may be OK. The spine
and short ribs can be easily seen, but the individual
vertebrae are not really apparent. The short ribs
appear scalloped. The upper surfaces of the short ribs
can be felt. One-half to a third of the length of the
transverse processes is visible. The hooks and pins
stand out. No fat can be felt on the pin bones. The
ligaments are sharp and easily seen. The areas around
the tail head and the thurl area are very dished. There
are folds of skin between the tail head and pins.
20. BCS = 2.5
It is a reasonable goal not to have more than 10
percent of the herd scoring 2.5 or less. This is the
lowest acceptable condition score. A cow with a score
of 2.5 has vertebrae showing but they cannot be seen
as individual bones. The short ribs can be counted but
are not scalloped. One-third to a quarter of the length
of the transverse processes is visible. The ligaments
are easily seen but not as sharp as with a BCS of 2.0.
Both the hooks and pins are angular but some fat can
be felt on the pin. The areas around the tail head and
thurl are dished.
21. BCS = 3.0
This cow could be a healthy, high-producing cow. But, if a cow
calves in at a score of 3.0 or less, she may not have enough body
fat to use for high peak milk production and to carry her
through until dry matter intake increases. At this score, the dish
of the rump (thurl) is at the transition between looking like a
“U” and looking like a “V”. Any cow under a BCS of 3.0 has a
thurl area looking like a “V”. The backbone can be seen but the
individual vertebrae are rounded. Covering the short ribs is half
to one inch of flesh. Less than quarter the length of the
transverse processes is visible. There is fat covering the
ligaments but they are still obvious. The hooks and pins have
some fat that can be felt. The area around the tail head is dished
but no folds of skin are seen.
22. BCS = 3.5
Dry cows and calving cows should have a body
condition score of 3.5. On this cow, fat can be felt on
the backbone, short ribs, and ligaments. The hooks
and pins are rounded. No individual transverse
processes can be seen. The thurl is somewhat dished.
The coccygeal (tail head) ligament is barely visible but
the sacral ligament can still be seen. The area around
the tail head is rounded and filled in but not fat.
23. BCS = 4.0
Cows calving in at this condition will eat less, lose
more weight and have more metabolic problems. This
cow’s back is flat because fat has filled it in. The short
ribs can not be seen individually but they can just
barely be felt. The hooks and pins are obviously fat.
The “U” between the hooks and pins is very flat with
no depression. The ligaments cannot be seen. The
area around the tail head is filled in and folds of fat
are seen.
24. BCS = 5.0
This cow is extremely fat and will have metabolic and
breeding problems. The backbone and short ribs
cannot be seen and are hard to feel. The hooks and
pins are buried in fat and hard to feel. The thurl is
totally filled in. The tail head is buried in fat.
25.
26. Reproductive Equation
Pregnancy rate = cow fertility% x Semen Fertility% x
heat detection % x Insemination efficiency%
Pregnancy rate is the number of animals that become
pregnant per 100 Inseminations.
27. Cow Fertility
Cow fertility is influenced by many factors.
The age of the animal has a strong influence on fertility.
Heifers and second lactation cows are usually more fertile
than first lactation cows and mature cows.
Fertility is highest in the coolest months of the year, and
when cows are:
Free of reproductive diseases;
Free of problems at calving;
Free from nutritional imbalance—especially if the cow is not
too thin or too fat at the time of calving. Fertility is also high
when cows stop losing weight and begin to replenish body
stores a few months after calving.
28. Heat Detection Efficiency
Poor heat detection efficiency is probably the single
most important factor affecting the pregnancy rate of
otherwise fertile cows. Heat detection efficiency is
made up of two components: the level of detection
and the accuracy of detection.
Heat detection accuracy may be low because:
The herdsman is not familiar with the signs of heat
and fails to correctly identify the cow(s) in heat;
Heat is correctly detected, but an error occurs in
determining the cow’s identification or in recording
the event (e.g., incorrect date).
29.
30. The onset of heat activity follows a distinct pattern,
with most activity occurring in the late evening,
through the night, and in the early hours of the
morning.
Research shows that more than 70% of mounting
activity takes place between 7:00 at night and 7:00 in
the morning. In order to detect more than 90% of the
heats in a herd, cows should be observed carefully in
the early hours of the morning, the late hours of the
evening, and at four- to five-hour intervals during the
day.
31. Insemination efficiency
this factor is measured primarily by the competence
of the herdsman and inseminator to:
Determine the correct timing of insemination;
Handle the frozen semen correctly;
Deposit the thawed semen accurately at the entrance
of the uterus.
32. Synchronization
This is designed to eliminate the need for heat
detection before insemination through what is know
as Timed Artificial insemination.
producers have a reliable system that results in
acceptable pregnancy rates to timed AI.
It involves taking control of the estrus cycle using
drugs to bring the cow on heat.
This system is a useful management tool the world
over.
33.
34. advantages
Avoids the human error in heat detection
Early rebreeding of non Pregnant cows thus reducing
the open days.
Solves the problem of silent heat
Treats cases of cystic ovaries.
35. Consist of giving GnRH on day 0 then PGF2α 7 days
later. A second injection of GnRH is given 48 hours
later, and finally timed artificial insemination is done
after 16-18 hours.
This protocol has a 80% success rate in dairy cows.
36. Incorporation of Timed Artificial Insemination in
dairy herd reproductive management programs
reduces labor requirements for detection of estrus
while improving overall reproductive performance
and maximizing profits.
