Benefits of Aspergillus Oryzae Extract in Transition Dairy Cows

Transition of cows from late gestation to early lactation is challenging for both animals and
dairy farmers. The period at the end of the dry period and the beginning of lactation in dairy
cows is commonly known as the transition period. Traditionally, transition period was
considered as the 3 weeks before calving and the 3 weeks following calving. However, with
the increasing understanding about cow’s physiological and metabolic changes, this period
has been recognized as the 60 days before calving and the 30 days following calving. The
transition refers to dairy cows going from a near maintenance state in late gestation, rapidly
changes to a state of increased metabolic and nutrient demands at the onset of lactation. This
period is extremely important in determining future health, milk production, and
reproductive success of the dairy cow. It has been suggested that up to 80% of metabolic
disorders or production diseases experienced by dairy cows during the transition period.
Managing the transition phase is important because cows are stressed due to fast growing
foetus and advanced pregnancy. Reduction in feed intake and low immunity make them
vulnerable to metabolic and infectious diseases – mastitis, metritis and have poor hoof
strength. The period is considered as most critical because of the long-term health and
productive consequences. The root cause of transition cow challenges is complex and in most
of the cases multifactorial.

Energy requirement and negative Energy Balance:

The transition period of dairy cow is characterized by a sharp decline in dry matter intake and
the negative consequences in dairy cow’s health and productivity after parturition. During the
transition period, nutrient requirements increase to support foetal growth and milk
production. The energy requirements of a recently calved cow are so significant that most
dairy cows do not initially eat enough to meet the requirement. The gap in the energy
requirement along with increasing milk production results in negative energy balance. To cop-
up with the requirement cows mobilize energy from body reserves, mostly from the body fat
stores. In extreme cases, degradation of muscles and bone may take place. The more time a
fresh cow spends in a negative energy balance, the higher the probability she will have a
health challenge. Hence, management of reduction in the amount of time the cow spends in
a negative energy balance is of utmost importance.

Metabolic and Physiological changes:

Due to mismatch in the required calories and the energies generated from dietary intake
during transition period, cows most often mobilize energy from stored body fat. Decrease in
dry matter intake around the time of calving may be one of the main problems with metabolic
homeostasis in dairy cows. The blood Ca concentration starts decreasing in the 1 to 2 days
before calving and reaches its lowest point within 48 hours of parturition.

The prevalence of clinical hypocalcaemia has decreased in the last few years. However,
subclinical hypocalcaemia remains a significant problem affecting over half of multiparous
high yielding cows. Subclinical hypocalcaemia is mostly associated with impaired postpartum
health and with decreased milk yield.

Excessive lipolysis and increasing levels of non-esterified fatty acids (NEFA) takes place blood
during this span. It is often associated with the accumulation of triglycerides in liver cells and
impairment of liver function resulting in an elevated ketone production and predispose
animals to ketosis. Along with increased NEFA concentration, there is subsequent
accumulation of beta-hydroxybutyric acid (BHBA) in the blood. These changes are considered
normal as a part of adaptive process in high yielding cows; involves an orchestrated series of
changes in metabolism that allow an animal to adapt to the challenges of the altered state.
However, when a cow fails to adapt to these metabolic challenges, several metabolic and
infectious disorders took place and affect the productive and reproductive efficiency.

Pro-inflammatory cytokines such as IL-1β, IL-6, and TNF-α are mainly released by
macrophages located at different organs like liver, brain, and adipose tissue. The fat
mobilization associated with the reduction in DMI during the period is considered responsible
for the release of these pro-inflammatory cytokines into the bloodstream. Besides high
growth hormone (GH) concentration, animals in negative energy balance shows insulin
resistance and reduced glucose uptake by peripheral tissues.

All metabolic processes are interconnected with each other. If there is a failure of one
metabolic process, it will impact on the efficiency of others. Such effect may persist beyond
the transition period; can be a major risk factor for subsequent productive and reproductive
performance.

Immune Status:

One of the major negative impacts of poor transition cow management is immune-
suppression. Immune status of animals decreases in and around parturition due to interaction
of several factors. In peri-partum period, both humeral and cell mediated immunity get
depressed due to the increased cortisol concentration. The week prior to and immediately
after parturition, leucocyte proliferation is higher but antibody production ability in response
to mitogen (non-specific stimulants of immune cells) is decreased. The serum concentration
of components of immune system such as immunoglobulin and complement factor also
decreases at the time of parturition in dairy cow. Thus, the depressed immune system of the
cow around calving, associated with the dramatic changes in circulating metabolites is
hypothesized the basis of the high disease incidence postpartum and the subsequent low
performance. On the other hand, negative energy balance due to reduction in DMI during
transition period leads to suppressed immune function that may promote uterine diseases
and other metabolic diseases.

Diseases and Disorders during Transition period:

Maladaptation to the physiological or metabolic changes may result in excessive fat
mobilization, dysregulation of inflammation, immunosuppression, and, ultimately,
metabolic or infectious disease in the postpartum period.
Diseases that result from disruption in homeostasis of rumen function, calcium and bone
metabolism; energy metabolism, protein metabolism and immune function. These
conditions are often inter-related, leads to:

• Hypocalcaemia and downer’s cow syndrome
• Hypomagnesaemia
• Ruminal Acidosis
• Ketosis and fatty liver
• Udder oedema / Mastitis
• Abomasal displacement
• Retained placenta
• Metritis
• Poor fertility and
• Poor production
• Other clinical and subclinical conditions

In adult dairy cattle, 80% of disease costs occur in the first four weeks after calving. This is
also a peak period for involuntary culls and deaths.

Management of Transition period:

The prime objectives of transition cow management are:

• To increase dry matter intake and energy supply
• Prevention or control of Ruminal Disruption
• Prevention of Macro and Micro mineral deficiencies
• Minimizing Lipid Mobilisation disorders
• Management of Stress and to optimize Immune functions Dr

An integrated approach to managing transition cows is needed if these challenges are to be
dealt with effectively. Therefore, an integrated transition diet should comprise of energy
and protein supplement, macro-minerals and DCAD, micro-minerals, rumen modifiers and
buffers and other immunity enhancement additives. If these challenges are addressed
during the transition period, a successful lactation and health status of the animals can be
established.

The management practices for transition cows must be focused on maximizing dry matter
intake and modulating stress and inflammation. To maximize dry matter intake, diet
composition especially fibre and energy concentrations is one of the most critical factors.
Other cow comfort parameters like control of heat stress, stocking density, bedding
management etc. are essential to minimize stress during the transition period

Benefits of Yeast Extract (Aspergillus Oryzae) in the management of Transition Cows:

Yeast extract is a natural product which is rich in proteins, amino acids, enzymes, nucleotides
and a variety of minerals. Its application as animal feed additive is proven and supported by
many research publications; however, their full potential has not been realized yet. In dairy
cows, supplementation of yeast extract has been found to be very useful to prevent ruminal.

disturbances, increase in dry matter intake, utilization of fibre and other nutrients and
thereby improves overall improvement in body conditions. Aspergillus oryzae (AO) extract is
considered as a precision prebiotic that enhances digestibility by amplifying the nutrient
supply for maximum performance. Aspergillus oryzae extract contains wide variety of
polysaccharide and amylase enzymes, which increases rumen function by enhancing fibre
digestion and reducing the transient post-prandial drop in ruminal pH. The combined effect
of such additive help cows to adapt from high roughage diets to higher concentrate diets
especially in the transition cows. An increase in feed digestibility due to the prebiotic would
lead to an increase in nutrient absorption. The increase in rumen fermentation and VFA
production improve overall energy supply and metabolic profiles. It helps in reduction in
rumen lactic acid concentration. by stimulating lactic acid utilizing bacteria and thus minimize
nutritional stress due to subacute acidosis. The extra energy made available to the cow
support for a healthy transition. Evidence suggests that supplementation of yeast extracts
provide a substantial benefit to transition cow during immune challenge through improving
availability of energy. Besides, the prebiotic AO supplement decreases the number of
cytokines and other inflammatory metabolites and thereby reduce levels of stress and boost
immune function.

Conclusion:

The transition period constitutes a turning point in the productive cycle of the cow as it
encompasses a number of changes on the cow which are in physiological transit from one
lactation to the subsequent lactation and hence it requires proper management for successful
dairy farming. General management practices of transition cows include control of
hypocalcaemia (milk fever) and feeding of propylene glycol or glycerol as an energy source.
Such strategies have some benefits in addressing a particular problem, however transition
cow challenges are complex and multifactorial that needs integrated nutritional strategies.

An integrated transition diet should comprise of energy and protein supplement, macro-
minerals and DCAD, micro-minerals, rumen modifiers and buffers and other immunity
enhancement additives. To meet specific objectives in support of the transition cow,
adequate nutrient supplementation and specific additives to be provided that support and
enhances rumen function, nutrient absorption and immune functions. Recently, several
fungal and yeast cultures or extract as feed additives have demonstrated significant beneficial
effect in improvement of health, productivity and combating stress in dairy cows. Aspergillus
oryzae is considered as a precision prebiotic that improves rumen function, enhances
digestibility, improvement in overall energy supply and metabolic profiles and enhances
immune functions.