What is Glycal Forte®?
Glycal Forte® is an off-white powder, sold in pallets of 40 x 25kg bags. Glycal Forte® is produced by a unique, patented process from liquid glycerol and a calcium source. It is classified as a ‘nutricine’, which is a bioactive component that increases the total nutritional value of the diet over and above the sum of the individual constituents. In the case of Glycal Forte®, this is achieved through its effect on rumen pH, leading to better feed utilization and improved microbial protein production.
How much Glycal Forte® should be fed?
250g per cow per day is the recommended feeding rate.
How is Glycal Forte® fed?
When fed in a TMR, Glycal Forte® is best mixed with dry feeds prior to loading in the mixer wagon. This allows good dispersal throughout the ration. Adding Glycal Forte® to the top of forages in the feeder wagon may result in uneven distribution and intakes.
Can Glycal Forte® be included in a compound feed?
Yes, tests have shown that Glycal Forte® retains its unique features of rumen pH conditioning, increased microbial biomass production and provision of highly available calcium and bypass glycerol when incorporated in compound feed.
How long should Glycal Forte® be fed for?
The best cost: benefit in most situations will be achieved when Glycal Forte® is fed to close-up dry cows (for a few days pre-calving) and freshly calved cows (approximately one-month post-calving). There are other situations where prolonged feeding of Glycal Forte® can benefit herds, e.g. herds with on-going sub-acute rumen acidosis (SARA) problems, including due to heat stress, or farms intentionally feeding rations with high sugar and starch levels.
Low rumen pH for about a month after calving is an inevitable response of cows moving from a dry cow to a milking cow ration – complete rumen adaptation takes this long. The low rumen pH during this period contributes to the inevitable post-calving negative energy balance (NEB).
What benefits should been seen from feeding Glycal Forte®?
All cows are in negative energy balance (NEB) and lose body condition for a period after calving. By improving the energy balance of cows after calving, Glycal Forte® reduces body condition loss. This leads to improved fertility and increased milk yield. Reduced levels of other diseases/disorders, e.g. lameness, mastitis, metritis and displaced abomasum, can be seen from a combination of improved energy balance, increased feed intakes and, therefore, improved immune response. In addition, correction of subclinical hypocalcaemia, common, especially in older cows, will reduce the risks of the conditions above. Increased microbial protein and the supply of bypass glycerol will help to improve the metabolic status of the cow.
What are the 4 features of Glycal Forte®?
Glycal Forte® optimises rumen pH, increases the production of microbial protein, provides bio-available calcium and supplies bypass glycerol, an energy source for the liver to make glucose. Taken together, these features form a Dynamic Metabolic Management System.
Why is Glycal Forte® unique?
Firstly, its dynamic rumen pH effect is different from other products. Glycal Forte® dissociates and releases acid-neutralising anions depending on rumen pH, i.e. on-demand. This means that it is effective over a wide range of rumen pH values and has a consistent effect 24 hours a day. It also means that it supplies glycerol to the rumen more slowly than glycerol drench, which explains the observed increase in microbial biomass. Secondly, it is unique in having these rumen effects, as well supplying bio-available calcium and bypass glycerol. Thirdly, by working on your farm with your cows, we build up an accurate picture of your cows’ needs and treat accordingly; the most efficient use of all resources.
How does Glycal Forte® compare with buffers?
Buffers may be cheaper to buy, but how effective are they? Sodium bicarbonate is highly water-soluble and quickly passes out of the rumen. Some work suggests its pH effect is via increased DMI and water intake, leading to increased rumen outflow and hence reduced starch digestion. Calcium carbonate, as ground limestone, is largely insoluble in the rumen and therefore ineffective as a buffer. Laboratory tests have shown that the active pH-optimising component in Glycal Forte® corrects the low pH of acidic rumen fluid more effectively than sodium bicarbonate or calcium carbonate.
What is all this fuss about low rumen pH, anyway? What are its effects?
If the rumen pH is too low, it can affect cows in four ways. Firstly, it reduces feed intakes by up to 10%, potentially more than 2 kg in a typical dairy cow. Secondly, it reduces the ability of rumen microbes to digest food, in particular, the fibre/forage components; their digestibility can be reduced by up to 20%. Thirdly, rumen bacteria have to ‘spend’ energy to survive at low pH – this energy comes from the energy contained in the cow’s feed. Fourthly, the ‘Leaky Gut’ theory proposes that, when rumen pH is low, energy is also lost via an underlying increased inflammatory state. Therefore, improving rumen pH improves the cow’s energy balance.
Why is a cow’s energy balance important?
At a simple level, more energy equals more milk. Hence the energy in cow rations equates to M + however many litres of milk you want/expect her to give. However, much more important, even vital, is energy balance in early lactation. If a cow suffers excessive negative energy balance (NEB) in the first 3 weeks after calving (and it appears that this affects up to 50% of cows in the UK), she will be more likely to:
- suffer from a range of metabolic disorders/diseases
- give less milk in the whole lactation
- take longer to get back in calf and
- be more likely to be culled early
All this comes at a cost to the health and welfare of the cow – and at a financial cost to the farmer.
What about the calcium in Glycal Forte®?
Although it is recommended to feed Glycal Forte® to both close-up dry and freshly calved cows, don’t regard calcium in Glycal Forte® as a means to control milk fever. This should be addressed by other strategies. However, subclinical hypocalcaemia is recognised as affecting at least half of cows in lactation 3 and above, in the period after calving. The effects of subclinical hypocalcaemia are similar to those of excessive NEB above, i.e. increased risk of disease and culling and poorer yield and fertility. The calcium in Glycal Forte® will help to reduce these risks.
What about the glycerol in Glycal Forte®?
Glycerol is an energy source. It is either used by the rumen microbes or, if it is released in the abomasum, by the liver to make glucose. Glycerol from Glycal Forte®, which is released in the rumen, is used more efficiently than glycerol given as a drench when more of its energy is lost as gas (carbon dioxide and methane). However, if the glycerol is released in the abomasum, as rumen bypass glycerol, it is absorbed and used by the liver. The relative amounts of glycerol released in either the rumen or abomasum depend on rumen pH.
How much does Glycal Forte® cost? What is the expected cost: benefit?
At a feed rate of 250g per day, Glycal Forte® costs 60p per cow per day. If Glycal Forte® is fed for 6 weeks around calving, as recommended, the total cost is £25.20/cow.
Several published studies have looked at the cost of excessive negative energy balance (NEB) or sub-clinical ketosis (SCK) in dairy cows. The calculated cost of SCK ranged from £47 to £230 per every cow in the herd. Find out more.