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Frequently Asked Questions


What are the advantages?

Agrimin boluses are a proven, convenient and cost effective way of ensuring each animal receives the correct amount of nutrients, every minute of every day for an extended period.

How do they work?

Agrimin boluses are given to the animal orally and are retained in the reticulum. Nutrients are released over an extended period of time through a process of erosion and dissolution.

Are they effective?

Our bolus ranges have been developed with input from Glasgow University Veterinary School. Many farm trials have been conducted to demonstrate efficacy and the results written up and published in peer-reviewed journals. Please contact us for a list of these publications.

Are all boluses the same?

No. There are a number of different bolus technologies available on the market with different mechanisms for releasing nutrients and for ensuring retention. Customers should make sure that the manufacturer can tell them how much of each nutrient is released over how long a period and what is the mechanism to ensure that the bolus stays inside the reticulum for the claimed period.


When is the best time to give Agrimin trace element boluses to dairy cows ?

There is a choice.  Either link the bolus to:
• the feeding strategies and seasonal change, or;
• target particular points in the cows production cycle such as drying off.

Feeding strategies:  Use the bolus when the animals are dependent only on forages with no supplements/cakes or concentrates in the dairy parlour.  In forage-based systems, the bolus can be used when greatest scarcity is likely to occur (the dry season; the winter; periods of nutritional deficit etc.)
Drying off:  This is 2-3 months before calving.  Dry cows tend to be handled at that time (hoof work/intra-mammary treatments etc.) so administering the bolus is not much extra work.  The aim is to improve reproductive performance and udder health in the next lactation whilst helping to ensure a good, clean calving.

When is the best time to give Agrimin boluses to dairy heifers ?

The farmer has a choice
• To any animal over 150 kg.
• To bulling heifers, 1 month before the introduction of the bull.  There is a demonstrated benefit between selenium and vitamin E on conception rates.
• As a routine treatment in mid-pregnancy for in-calf heifers. This provides a boost of trace elements to the heifer and then covers the period of rapid foetal development and early lactation.

When is the best time to give Agrimin boluses to beef cows ?

Mid pregnancy:  This provides a boost of trace elements to the cow and then covers the period of rapid foetal development and early lactation.
Autumn or spring:  An effective and simple alternative is to dose the animals with the bolus at certain points in the calendar when they are handled i.e. before housing in winter or turnout in spring.  This suits the management practices of many farmers.

When is the best time to give Agrimin boluses to growing beef animals?

Any growing animal over 150 kg that is likely to be at risk from a trace element deficiency.  This deficiency could be related to seasonal shortages i.e. winter.  This will allow them to achieve their growth potential if other nutritional inputs (protein and energy) are satisfied and ensure a regular and uniform provision of trace elements.

Can boluses be given to calves?

For ruminating calves over 6 weeks of age that are out on pasture or are on a forage based diet, they can be given Rumbul Magnesium Bullets for sheep/calves, smAll-Trace for calves or 24•7 4g copper capsules. For convenience, calves can be given boluses at turn-out or at housing.

What type of sheep are good candidates for boluses?

The target animal is the breeding ewe that is extensively reared and where the grass and forage based diet may have inadequate levels of trace elements.

When should breeding ewes be given Agrimin boluses?

The pre-tupping ewe should be given a bolus at least two weeks prior to tupping. Another opportunity is to give the ewe a bolus at scanning so that she receives supplementation through lambing and up to peak lactation. Boluses can also be given to over-wintered lambs (of at least 40kg liveweight) in late Autumn.

Why use an Agrimin 24•7 Calcium bolus?

Agrimin 24•7 Calcium is a vehicle for a large supply of calcium (43g in each bolus). This calcium is available to the animal over a 36 hour period and is an excellent way of ensuring a constant supply of calcium during calving and immediately afterwards. Also, many herdsmen say they prefer to give a bolus at this time, as it is quicker and easier than other methods of calcium supplementation.

When is the best time to use Agrimin 24•7Calcium?

Many farmers start using Agrimin 24•7 Calcium after calving and after they have given cows a bottle of calcium borogluconate. If they find this regime successful they will try and give a bolus to cows before calving and will perhaps follow up with another bolus post calving.


Will there always be blood (plasma) copper response to using boluses ?

Blood copper levels can be a useful, but not infallible, guide to the copper status of cattle.  The main store of copper is in the liver from which copper can move in and out to reflect both dietary supply and the demands for growth, pregnancy and lactation.  An analogy would be deposit and current bank accounts.  The following figure shows a generalised relationship between copper in blood plasma and liver copper levels.  When the threshold level of blood plasma is reached, further increases are not observed but there continues to be a build up in liver copper.

Relationship between blood plasma copper (mol/l) and liver copper (mg/kg DM).

Significant responses to Agrimin boluses are observed in animals with copper plasma levels below 9 mol/l.  A response is not generally seen when the plasma value is above 12 mol/l but there is a build up of copper in the liver.  Remember a bolus is designed to give a trickle dose, unlike drenches.

Will Agrimin boluses work in the presence of Molybdenum (antagonists) ?

Molybdenum in your pasture might affect the bioavailability of copper through the formation of insoluble copper thiomolybdates in the rumen or then in the blood stream.  Our All-Trace boluses have been tested on suckler cows grazing high molybdenum pastures (4.4 mg/kg DM) on a reclaimed mine site near Logan Lake, British Columbia. The experiment demonstrated that prolonged periods of molybdenum-enriched forage consumption will result in increased concentrations of molybdenum in the serum and liver of cows and calves.  Supplementing animals with All-Trace boluses significantly enhanced liver copper storage, while effects on blood plasma copper were minimal.  (Popp et al 1995).   A survey of trace element concentrations in Scotland (SAC 1982) indicated that pasture levels of molybdenum and sulphur rarely exceed 1.5 mg/kg DM and 3.0 mg/kg DM, respectively.  Therefore, the likelihood of no response to copper supplementation is small.

In small cattle can I reduce the recommended administration regime ?

No !  Always follow the instructions on the pack. Some farmers are tempted to use a single All-Trace bolus in smaller cattle. All-Trace is always a 2 bolus dose as the trace elements are released by a combination of abrasion and dissolution.  The boluses have to rub against each other to ensure the correct release of nutrients.

Are the Agrimin boluses compatible with anthelmintic boluses ?

Generally, yes.  If you have any doubts, please contact Agrimin and we will give advice that is more detailed.

Is copper oxide in the bolus an effective source of copper ?

Yes.  Parkins et al (1994) demonstrated that sustained-release rumen boluses significantly increased blood (P<0.05) and liver (P<0.001) copper concentrations in growing Suffolk-cross wether sheep.  The amount of copper stored in the liver was thus about 7.1% of that released.  This is comparable to the bioavailabilty of copper oxide needles administered to sheep (8.3%).

Can slow release boluses be used to treat clinical conditions ?

Other than Rumbul Magnesium Bullets which are licensed for the prevention of hypomagnesaemia, all of our other boluses are sold as dietetic complementary feeds and we make no clinical claims.  The principle behind the our boluses is they deliver a consistent daily dose of trace elements.  The bolus should be used as part of a supplementary feeding programme to prevent the depletion of essential elements.