Not only has gentics and nutrition played a major role in maximizing milk production, but farm management, labor, and facilities all play a role as well. Jaylor's Ruminant Nutritionist, Janet Kleinschmidt, discusses how in PART 2 of this presentation.

1. The Rumen & the (TMR)
Wagon Part II

2. Chemical & Effective Fibres
When dairy nutritionist talk about chemical &
effective fibres nutrition they are generally
referring to:
ADF, NDF, NSC and eNDF.
The names refer to the types of detergent solutions
that are used to measure the forage fibre in an
analysis laboratory

3. ADF & NDF: The Chemical Fibres
The ADF fraction contains a higher proportion
of true indigestible or slowly digestible
cellulose & lignin.
ADF is a good indicator of plant or dry matter
digestibility. The higher the ADF, the less
digestible the forage or ration will be.

4. ADF & NDF: The Chemical Fibres
The NDF fraction contains all of the fibre
components that represent “bulk”.
NDF is a good indicator of the “dry matter
intake” ability of a forage or feed. The higher
the NDF, the less an animal can consume.

5. ADF & NDF: The Chemical Fibres

6. ADF & NDF: The Chemical Fibres

7. NSC (Non structural carbohydrate)
NSC describes the non-NDF fraction and is
composed primarily of sugar, starch and
pectin.
In rations for high production groups (i.e. >30-
35 kg/head/day), I like to see NSC %
between 35% and 40%.
Ideally I do not like to see NSC > 37%
ACIDOSIS!!!

8. ACIDOSIS!!!
Diets that are rapidly fermented in the rumen
lead to rapid production of VFA (i.e. NSC>
38% or deficient in eNDF).
When VFA production exceeds the ability of
the rumen environment to neutralize or
absorb the acids, sub-acute ruminal
acidosis occurs.
An episode of ruminal acidosis occurs when
the pH in the rumen drops 5.8.

9. ACIDOSIS!!!
I am extremely cautious with my herds to avoid
acidosis.
The recovery period is 1-3 years and the cost
to the producer in terms of herd health and
productivity is huge!

10. Effective Fibre: The Physical Fibre (eNDF)
When nutritionist talk about the physical
attributes of fibre they refer to it as the
“effective fibre”.
Historically, fibrousness was related to
chewing activity and effectiveness was
related to milk fat depression.

11. Effective Fibre: The Physical Fibre (eNDF)
When eNDF is decreased or inadequate:
 Less chewing by animal
 Less salivary buffer secreted
 More rumen acid produced
 Reduced ruminal pH
 Shift in microbial populations & end
products of fermentation (>propionic
acid,<acetic acid)
 Milk fat depression
 Acidosis, sick & unproductive animals
(long term!)

12. Effective Fibre: The Physical Fibre (eNDF)
This tenuous situation is further complicated
by the trend towards finely cut and
processed forages, and a range of by-
products that offer very little chemical or
effective fibre

13. Penn State Shaker Box

14. Particle Sizing: A Tool for Evaluating Forages &
TMR’s
There are many steps between the ration on
paper and the ration consumed by the cow
that can cause “ration break down”.
These would include:
1. Loading and delivery accuracy
2. Mixer design
3. Loading sequence
4. Mixing time
5. Animal sorting

15. Particle Sizing: A Tool for Evaluating Forages &
TMR’s
An important point, which in my experience, is too
often forgotten, is mixer maintenance and
cleaning.
 Worn, broken or missing parts do not allow the
mixer to function uniformly.
 A schedule must be in place to sharpen, replace or
rotate knives. Drastic changes in forage particle
break down can occur if they are done all at once.
 Build-up of wet feed stuffs can also impair mixer
function and inhibit uniform distribution of
nutrients.

16. Particle Sizing: A Tool for Evaluating Forages &
TMR’s
Reducing particle size has been shown to improve the
dry matter intake potential of diets, particularly if
poor quality forages are involved.
However, adequate particle size in the ration is
necessary to avoid depressed milk fat and to
maintain a healthy rumen.

17. What, exactly, are they eating?
We've looked at the producers role in TMR’s, we’ve
considered the nutritionist’s perspective.
What role does the cow play?
Nutritionist refer to 3 rations that exist:
1. The ration formulated on paper.
2. The ration offered to the cow
3. The ration eaten by the cow
There can be huge differences between these 3
depending on mixing accuracy and cow behaviour.

18. What, exactly, are they eating?

19. What, exactly, are they eating?
The previous tables show results when researchers fed
cows a well balanced and mixed TMR.
By sorting, cows ate finer forage and concentrates
almost exclusively during the first 12 hours, setting
themselves up for acidosis.
During the last 6 hours the cows were forced to eat
more of the longer particles that had been sorted out
earlier.

20. What, exactly, are they eating?
So what's the big deal?
 Less rumination and cud chewing.
 Digestive upsets and fluctuation in intake.
 A drop in milk production and reproduction.
 Low or erratic butterfat tests.
 Laminitis, sole ulcers, white line disease etc.
 Higher incidences of displaced abomasums.
 Depressed immune system, body abscesses.

21. What, exactly, are they eating?
How can we prevent “sorting”?
 Ensure total ration moisture is between 46 to 55%. If
too dry, add water or products such as wet brewers
grains.
 Limit dry hay (or straw in the case of heifers and FAD
cows) to 1 to 2 kg/hd/day.
 Limit maximum fibre length to 5 cm or less.
 Processed corn silage helps; the presence of husks
and cobs in the TMR promotes sorting.
 Provide free choice sodium bicarb.

22. The Rumen & the (TMR) Wagon
A balanced ration will allow for
proper digestibility, good dry matter
intakes, and satisfactory feed utilization.
A ration should be developed with
profitable levels of milk and components in
mind.
TMR designers, nutritionists and producers should not
overlook the physical aspects of the ration, such as
minimum forage required, maximum
levels of concentrate to feed, eNDF, and palatability.