Manipulations of rumen function that can augment livestock productivity are;  Correction of concentrate to roughage ratio  Feed bypass or escaped nutrients  Defaunation of rumen  Use of yeast as probiotics  Use of anaerobic fungi  Use of other feed additives

1. Manipulation of rumen function
to augment livestock productivity
SUBMITTED TO: DR. IMAD RASHEED
SUBMITTED BY: UMAR FAROOQ (2019-AG-349)

2. Introduction
The rumen has a very complex eco-system of anaerobic micro organism
bacteria, protozoa and fungi representing various microbial groups.
These organism in ruminants are responsible for degradation of complex
dietary fibers which makes major component of their diet.
The rumen environment has a very strong buffering action due to
capacious production of saliva, which contains salts of phosphate and
bicarbonates but microbial diversity and size, as well as activities of
microbial population, which governs the rumen function, is under the
influence of dietary conditions, specially its composition.

3. The efficiency of microbial fiber digestion in rumen depends upon the
level of coordination between microbes and the host animal. In this
symbiotic system, the host animal constantly maintains the favourable
environmental conditions in the rumen and continuous supply of plant
materials.
In return, the rumen microbes degrade the complex dietary
carbohydrates and provide the animal with easily utilizable forms of
carbon or energy and protein sources as the microbial biomass. Thus
changes in feeding regimen or pre-treatments of feeds may cause a
remarkable diversion from normal microbial rumen activities.

4. Altering the feeding pattern in the
ruminant animal
The correction of concentrate to roughage ratio can show tremendous
effect on rumen activity.
Its functions can also be altered to the beneficial level by feeding
protected by-pass or escaped nutrients, prepared by physical, like
compaction of feed to make complete feed block or chemical treatments
including urea or ammonia treatment.
Incorporation of additives in the feed including probiotics, enzymes etc.,
and recently biotechnological approach like gene transfer has also been
tried.

5. 1. Correction of concentrate to roughage
ratio
Feeding of crop residues and dry grasses, rich in structural
carbohydrates, favours the type of microbial fermentation in the rumen,
which causes increase in population of methanogenic bacteria, which
result into increase in methane production.
Methane production is wastage of dietery energy.
Supplementation of concentrate to straw based diet can reduce methane
production in rumen. The saved energy can be utilized for production
purposes.

6. The rumen function can also be improved by the dietary mineral
(UMMB) or supplementation of starch rich concentrates and ionophores
like monensin/rumensin and antibiotics.
The beneficial effect of these supplements is achieved through reduction
in methane production and obviously increases the livestock production.

7. Urea can be recycled and used as a source of nitrogen for the rumen
microorganisms.
Urea is used in ruminant feeding both as fertilizer grade as well as feed
grade. It can be administered through feed along with other feed
ingredients in a compounded ration.
 Urea can also be given as liquid nitrogen i.e. it could be dissolved in H2O
and offered as drinking water to the animals.
 It could also be constituted as urea-molasses multi-nutrient feed block
held together by a binder. The animal by abreaction licks off urea from the
block. Experiment over the years have shown that urea could be utilized
as whole ingredient to feed at levels between 1% - 5% which defines a
save utilization level.

8. 2. Feed bypass or escaped nutrients
Feeding of protected or escaped nutrients is an indirect approach
to manipulate the rumen activity.
By feeding such nutrients the site of digestion of nutrients shifts
from rumen to lower digestive tract.
It is generally done to reduce the attack the proteolytic enzyme on
dietary protein in the rumen, and to increase the supply of amino
acids to duodenum.

10. The main benefit of ‘bypass’ protein is that;
The original amino acids in the protein meal are absorbed in the small intestine
instead of converted to microbial protein in the rumen, thereby providing a
different balance of essential amino acids for better animal nutrition hence,
production.
Another benefit of feeding meals with high ‘bypass’ protein is that the portion
of the protein that is rumen degradable (RDP) breaks down in the rumen very
slowly. This allows animals to source small amounts of protein over longer
periods for microbial protein production, long after urea has been degraded and
used in the rumen by the animals.
Small quantities of ‘bypass’ protein fed at strategic times, have an enormously
beneficial effect on production. ‘Bypass’ protein also provides an important
protein source when the animal’s requirements for protein exceed those
provided by microbial protein.

12. Degradation depends upon both the nature of the protein and the
length of time it remains in the rumen. As feed intake and
passage rate through the rumen increase, retention time in the
rumen and degradation decrease.

13. Feeding of fat depresses fiber digestion in rumen. It reduces acetic
acid production. The purpose of protected fat feeding in rumen is to;
Maintain the supply of long chain fatty acids to the animal.
Increase energy density of diet, as per unit weight, one unit of fat
give 2.25 times more energy than the carbohydrate or protein gives.
To intact production of acetic acid in the rumen.
The choice is always for the cheapest source of fat fed as calcium or
magnesium soap of fatty acid.

15. 3. Defaunation of rumen
The term defaunation represents the elimination of the microfauna,
protozoa from rumen. There are several defaunation techniques or
methods.
Defaunation can be done by prolonged starvation and copper
sulphate administration.
Heating the rumen contents to 50°C is safe but doesn’t remove all
of the small oligotrichs Diplodinium dentatum and Entodinium
species.
Defaunation can also be done with aerosol OT (Dioctyl sodium
sulfosuccinate) method.

16. It has been well establish that removal of ciliate protozoa from
rumen, results into an increase in flow of non-ammonia nitrogen and
bacterial nitrogen into the abomazum, suggested that more dietary
protein has been escaping degradation in the rumen, which is feed
for the ciliated protozoa.
This indicated the possibility to improve the ruminant productivity
through removal of ciliates population of rumen; however,
beneficial effects can be achieved in the animal fed low protein high
energy diets.

18. 4. Use of yeast as probiotics
The term “probiotics” comes from the Greek words “pro” (in
favour) and “biotic” (life). Probiotics are defined as “live
microorganisms that may beneficially affect the host upon
ingestion by improving the balance of the intestinal microflora”.
More recently Havenaar proposed the following definition: “Mono
or mixed cultures of live microorganisms which, when applied to
animal or man, beneficially affect the host by improving the
properties of the indigenous microflora”.
This latest definition is more specific in terms of the host and types
of microorganisms and not restricted to the intestinal microbial
community.

20. Probiotics/prebiotics have the ability to modulate the balance and
activities of the gastrointestinal (GI) microbiota, and are, thus, considered
beneficial to the host animal and have been used as functional foods.
Under stressed conditions, direct-fed microbials may be used to reduce
the risk or severity of scours caused by disruption of the normal intestinal
environment.
The observable benefits of prebiotics may also be minimal in generally
healthy calves, in which the microbial community is relatively stable.
However, probiotic yeast strains have been administered with the aim of
improving rumen fermentation efficiency by modulating microbial
fermentation pathways.

21. Limitations of Yeasts Probiotics:
An important part of the variability in the response to yeast
supplementation is due to variation in the yeast strain used, its viability
(survival during pelleting, for example), animal status and the nature of
the diet.
Another important factor to consider is the intrinsic variation between
animals of a same herd. In effect, feeding behaviour factors such as rate of
feed and water intake and physiological factors such as ruminal content
turnover and volume of saliva production are variable from one animal to
the other and may explain the discrepancies in the results reported from
different trials.

22. 5. Use of anaerobic fungi
Ruminal anaerobic fungi account for up-to 8% of the microbial biomass in
rumen and actively colonize plant cell-walls.
Observed in the rumen as early as 1910, but were believed to be
flagellate protozoa.
Confirmed to be a true fungus by the presence of chitin in its cell wall
and designated as Neocallimastix frontalis.
Identified anaerobic fungi in sheep rumen, each of which had a motile
stage (the zoospore) and a non-motile zoosporangium.
Found in the rumen and other parts of the gastro-intestinal tract of
herbivorous animals.

23. Play an active and positive role in fibre degradation as evidenced by the
presence of different hydrolytic enzymes.
There is a significant reduction in in-vitro gas production and
degradation of fibrous feeds, indicating a positive role played by fungi in
fibre degradation.
The fibre-based diets stimulate the fungal growth in the rumen of buffalo
in comparison to diets rich in easily fermentable carbohydrates.
These fungi prefer to get attached to the most lignified tissues of plant
feed material by producing variety of enzymes.

24. Potential benefits of ruminal anaerobic fungi for improved animal
nutrition and productivity:
Improved fibre digestion and nutrient utilization
More feed intake and feed efficiency
Increased body weight
Improved milk production

25. Prospective applications of ruminal anaerobic fungi:
Direct-fed microbials
Animal feed additives
Novel silage inoculants
For large scale production of enzymes (e.g. cellulase)

26. 6. Other feed additives used for
manipulation for rumen function
There are large number of feed additives like;
Ionophores
Antibiotics
Drugs
Herbal preparations
Micronutrients
Enzymes

27. These are commercially available and enhance animal productivity.
Galactogougas are said to augment milk production.
Ionophores are feed additives that alter rumen microbial populations
through ion transfer across cell membranes.
Ionophores like Monensin may have several advantages for dairy cattle,
including improved energy metabolism, increased milk production, and
altered milk component.
Lasalocid observed to inhibit proteolytic activity and deamination, and
methanogenesis, which is said to increase propionate production. Thus it
enhances the efficiency of feed utilization in the ruminants.

29. Summary
Manipulations of rumen function that can augment livestock productivity
are;
1. Correction of concentrate to roughage ratio
2. Feed bypass or escaped nutrients
3. Defaunation of rumen
4. Use of yeast as probiotics
5. Use of anaerobic fungi
6. Use of other feed additives

30. Reference
1. Strategies for sustainable livestock production by S. K. Kaushish
2. RUMINANT ANIMAL NUTRITION BY Prof. C. F. I. Onwuka
3. Defaunation: Effects on feed intake, digestion, rumen metabolism and
weight gain BY Arse Gebeyehu1 and Yosef Mekasha
4. BYPASS PROTEIN - THEORY AND CONCEPT by D.L. Harmon and T.G.
Nagaraja
5. http://www.ncbi.nlm.nih.gov
6. www.merckvetmanual.com