Page 16 - AWA-41-No.1 issue

DAIRY FARMING

A Selected NSPase Improves Feed Efficiency

eed is the number one expense for dairy farmers.
FFeed has the highest impact on production costs
and profitability. In recent years, due to a series of glob-
al events, the cost of feed has risen and the milk margin
over feed has shrunk. In 2023, we saw the price of dairy
compound feed increase by almost 25%. And on top of
that, there were high increases in other fixed costs such as
electricity and fertilisers (IFCN, 2023). One way farmers
can improve their profitability is by continuing to optimise
feed efficiency and performance in the herd.
Better feed efficiency reduces the cost of producing 1 kg
of milk and thus increases the margin over feed. A deeper
understanding of dairy nutrition and rumen fermentation Uruguay, both feed efficiency (Figure 1) and energy ef-
in the last decade has led to better feeding strategies. ficiency (Figure 2) were increased by 10%, and Hostazym
In addition, innovative feed solutions have been devel-
oped, helping improve feed efficiency, in particular for- X reduced the feed dry matter needed to produce 1 kg
age utilisation. Complex carbohydrates such as the fibre of ECM by 0.07 kg. Cows supplemented with Hostazym X
contained in forages are broken down by rumen bacteria utilised the feed more efficiently and produced more milk
into volatile fatty acids (VFAs) which are used as a source per kg of dry matter intake. The cows in the Hostazym X
of energy and for milk fat synthesis. group also produced 1.8 kg more ECM and 0.1 kg more
fat per day. As shown in the trial, Hostazym X is an efficient
Rumen fibre digestion is performed by several species of
cellulolytic bacteria of which Fibrobacter succinogenes, enzyme for use in dairy cow production with the potential
Ruminococcus flavefaciens, and Ruminococcus albus are to reduce input costs and increase herd profitability.
considered the most efficient (Xiaodong Chen et al., 2022).
Rumen fibrolytic bacteria are very efficient in breaking
down plant cell walls, but to start the process they first
need to attach to exposed cellulose (Weimer, 2022). The
cellulose in the plant cell wall is protected by hemicel-
lulose (and lignin) and this slows down the process, de-
laying rumen fibre degradation. One way to speed up the
work of cellulolytic bacteria is to use non-starch polysac-
charide (NSP) enzymes that can rapidly break down the
hemicellulose and expose more cellulose, making it avail-
able for the bacteria.
Efficient enzyme
Non-starch polysaccharide enzymes can be very efficient
in forage digestibility if they are properly understood and
if they meet specific requirements such as efficacy, speci-
ficity, and rumen stability. They can be an efficient tool for Figure 1. Feed efficiency in lactating Holstein dairy cows fed a
improving fibre digestibility and energy intake from for- control diet or the same diet containing Hostazym® X (University
ofthe Republic, Uruguay, 2024)
ages. One such enzyme is Hostazym X which is a xylanase
standardised enzyme with several complimentary enzy-
matic activities which target the hemicellulose part of the
plant cell wall.
Hostazym X is very efficient in ruminants due to its unique
combination of NSP activities, its stability in the rumen en-
vironment, its efficacy at a temperature of 42 oC, and its
pH range of 5-7. In the rumen, Hostazym X rapidly breaks
down the hemicellulose after ingestion, exposing more
cellulose for the rumen bacteria. This process increases
the efficacy of the cellulolytic bacteria and reduces their
lag time, speeding up the fibre degradation process.
Research data from various studies performed in differ-
ent countries using different local forages (including corn
silage, sorghum silage, and different hays and grasses)
show a significant increase in fibre digestion, an increase
in milk yield by 5%, and an increase in energy corrected
milk (ECM) by 6% in cows fed a higher neutral detergent Figure 1. Feed efficiency in lactating Holstein dairy cows fed a
fibre (NDF) diet (40% total NDF). control diet or the same diet containing Hostazym® X (University
ofthe Republic, Uruguay, 2024)
In a study carried out at the University of the Republic, Circle 20 on enquiry card
14 Vol. 41 No. 1