The maintenance of a healthy immune system is a fundamental feature of optimal herd health and performance, and this can be massively impacted by stress in cows.
Enhancing immunity has far-reaching impacts, not only on reducing disease incidences but also improving milk yields and fertility as well as reducing culling rates.
A healthy cow is more likely to be a productive and fertile cow and stay in the herd longer. With the growing pressure to reduce antibiotic use, farmers need to seek additional measures to maximise immunity, profitability, and animal welfare.
Stress in cows
Stress will naturally occur throughout the production stages of a cow. The transition period (about three weeks before and three weeks after calving) is a time when the cow is releasing large amounts of cortisol and she is under significant stress.
This cortisol release results in a natural decline in immunity, making the cow especially vulnerable to infections such as metritis and mastitis.
Other periods of stress can occur at drying off with a change in environment and nutrition, weather changes resulting in heat or cold stress, management challenges such as regrouping, overcrowding, feeding changes, oestrus or any treatments or procedures.
Whether stress events are unplanned or part of the normal production cycle, each event will result in a compromise of immunity and expose the cow to risks of disease and production losses.
White blood cells are part of the body’s innate immune system and first line of defence against pathogens and infectious agents. Neutrophils are the most abundant white blood cell in the body, and they are recruited early from the circulating blood to the point of infection where they kill bacteria.
A molecule called L-selectin is responsible for keeping neutrophils along the blood vessel wall where they can detect signals alerting them to go to a point of infection. L-selectin makes neutrophils more responsive and effective in destroying pathogens.
During stress, L-selectin levels decline, and this is one of the reasons immunity is naturally suppressed during any stressful event such the transition period.
A solution
OmniGen-AF is a unique nutritional speciality product that helps cows maintain an optimally functioning immune system, especially under stress.
It works by increasing L-selectin, helping the neutrophils receive the necessary signals and move quickly to the point of infection to fight pathogens.
By counteracting the negative impact of stress on immunity, OmniGen-AF supports the cow’s natural immune defences and makes them less vulnerable to disease which will reduce health events and improve productivity.
OmniGen-AF has been tested on over 650,000 dairy cows in herds throughout the US and Europe.
A 2020 publication from the University of Florida with nearly 1,400 multiparous Holstein cows showed at 2.5:1 return on investment due to increased milk production, better health and improved reproductive performance.
Testing
Cows were fed OmniGen-AF or a placebo from drying off through 150 days in milk. Cows fed OmniGen-AF produced 0.7 kg more milk each day relative to cows fed only the control diet (Fig. 1 below). Cows fed OmniGen-AF also had lower incidences of clinical mastitis and retained membranes.
Fig. 1: Increased milk yield in cows fed OmniGen-AF vs. control:
Other postpartum diseases such as mastitis, ketosis, and displaced abomasums were also numerically reduced (Fig. 2 below).
Fig. 2: Frequency of postpartum diseases in cows fed OmniGen AF vs. control:
Additionally, cows fed OmniGen-AF spent fewer days receiving antibiotic treatments relative to cows fed only the control diet. Feeding OmniGen-AF was also associated with a ten-day reduction in days open compared to feeding only the control diet.
When the economic analysis of these results was performed using milk market price, cost of additional feed required for increased milk production, and increased milk yield produced in the trial, OmniGen-AF resulted in an increased net milk income of €28.40/cow over 150 days.
Researchers also determined based on the reduced occurrence of diseases documented and the published costs of these diseases, a savings of €11.50/cow was achieved. A ten-day reduction in days open resulted in a savings of €24.60/cow, assuming an extra day open equals €2.46/day.
Net benefit of €38.30/cow
In summary, when factoring the additional income achieved through increased milk yield and savings from reduced health events and improved reproductive performance then subtracting the cost of feeding OmniGen-AF for 210 days in the trial, the result was a net benefit of €38.30/cow or a 2.5:1 return of investment over 150 days in milk (Fig. 3 below).
Fig. 3: Summary of increased profit and savings from feeding OmniGen-AF:
OmniGen-AF is fed to dry and lactating cows at 55g/head/day. The full immunity benefits will not be achieved until 6-8 weeks of feeding OmniGen-AF, so it is recommended to start at drying off to achieve enhanced immunity during the critical calving period.
Continuing through lactation will also combat the negative effects of stress throughout the lactation period such as nutritional and environmental changes.
Once OmniGen-AF is no longer being fed, the benefits will wane quickly within seven days.
Over 100 research publications on OmniGen-AF demonstrate improvements in immunity that correlate to reduced disease incidences and improved performance. OmniGen-AF offers a nutritional approach to enhancing immunity by combating the negative effects of stress on immunity in cows.
OmniGen-AF has been proven to reduce disease and antibiotic use, increase milk yield, improve reproductive performance, and enhance profitability on dairy farms.
By Dr. Lauren Popiolek, Interchem and PharVet veterinary technical advisor
More information
For more information on…
…contact your local PharVet representative via the details below:
- Denis O’Carroll: Territory manager (southwestern region) tel: 087 745 1750, [email protected];
- Aaron Feehily: Territory manager (western region) tel: 086 029 7273, [email protected];
- Dermot Heafey: Territory manager (southern region) tel: 086 0465045, [email protected];
- Aidan Hallen: Territory manager (east region) tel: 087 2536187, [email protected];
- Shane Geraghty: Territory manager (Northern Ireland) tel: 00444 7585, 608889, [email protected].
