Gut Adaptation to Healthy Starch Assimilation in Dairy Ruminants: A Lifetime DevelopmentAuthor(s): Akbar Nikkhah
?Ls perspective policy article describes a lifetime program to
e???ectLYeO\ adapt rumen and post-rumen ecology to starch
fermentation and assimilation. Such a program necessitates prolonged
nutritional management of dairy animals from just a??er birth when
concentrate feeding begins through heifer and dairy production cycles.
By an evolutionary de?nLtLon due to high dependence on natural
resources especially on pastures, ruminants have long developed
extensive rumen fermentation. ?Ls exceptionality enables utilization
of resistant plant cell wall ?bres using microbial enzymes symbiotically
[1,2]. Accordingly, only so much starch could have been supplied to
the rumen and post-rumen. Owing to such a limited starch nutrition
in nature, ruminants have not required extensive amylolytic capacity
particularly post-ruminally . However, due to modernization of the
dairy industry especially over the last few decades, nutritional and
health demands for e???ectLYe starch fermentation in rumen and
capacious starch assimilation and glucose absorption in small intestine
have increased. Collecting all of these optimums together has, thus,
become a serious challenge on-farm [3,4]. Consequently, unhealthy
and Lne?cLent rumen fermentation, Lne???ectLYe post-rumen starch
assimilation, and metabolic disorders (e.g., subacute rumen acidosis,
rumenitis, liver steatosis, laminitis, and immune malfunction)
frequently occur in today’s dairy farming [4,5]. ?e drama requires
feasible and pragmatic actions to overcome the challenges and improve
economics and food safety globally [6,7].
Pragmatically, timely adaptation of the ruminant gut to extensive
starch fermentation and assimilation requires a step-wise planning.
Reliance on prolonged milk supply and easily available pasture has
kept natural ruminants from early development of starch assimilative
capacity in both rumen and post-rumen. In modern farming, however,
such natural properties must be modulated to cope with the increasing
demand for higher production e?cLenc\ ?e latter obliges improved
production per unit of nutrient intake. Increased production can be
achieved merely through e???ectLYe nutrition of starch as a most
concentrated form of available energy for both microbes and the host
ruminant. In fact, improved milk and beef production e?cLenc\ stems
from increased microbial mass yield as a result of stabilized rumen
conditions. Notably then, any health-sustaining pathway must go
through successful starch nutrition.
?e industrial implication of this article involves allowing the living
gut to receive and assimilate adequate starch right from few weeks
post-birth in calves through heifer and adult cow production cycle.
However, this plan must not contradict with the conventional practice
to not overfeed heifers with high-energy diets that cause excessive
abdominal and peripheral adiposity and reduced fertility. In other
words, diets could have adequate starch and not be overly energydense. Additionally, to avoid over intake of energy, starch diets may be
fed at limited intake levels under constrained feeding programs.
In a nutshell, a sustainable strategy to improve starch dynamics in
the high-producing ruminant gut is to conduct the adaptation for the
entire commercial life from just a??er birth through multiple
production cycles. ?Ls requires systematic and well-managed starch
nutrition of calves, heifers and mature dairy cows. Such an adaptation
is not limited to short-term alterations in rumen microbial populations
and hepatic biochemistry. Harmonically, but the program works at
tissue, cell, and gene levels and helps build foundations for starchbased modern farm management. Research is a must to enlighten the
various aspects of the theory.