Southern Beef Situation

One of the first considerations is the plants and the soils inherent deficiencies which will determine animal performance and supplements required. To give a background as to our thinking and approach to a supplement program for the Southern Beef producer the following notes outline the parameters which we will be working with.

Pasture Plants.

Most native Australian grasses are summer growing or C4, Tropical grasses which are distinctly different from the cool season winter active Temperate grasses in that they utilise a different pathway for photosynthesis i.e. the conversion of sunlight, water and carbon dioxide to plant tissue. Native summer growing grass species such as Red grass, Kangaroo grass, Spear grass, Native Sorghum, the Mitchell and Blue grasses as well as the introduced Tropical species such as Kikuyu, Paspalum and Couch are all C4 plants. Grasses such as Rye grass, Cocksfoot, Fescue, Phalaris and the Clovers are all C3 plants and are essentially cool season plants.

Before we begin to talk about the animals grazing the summer growing natives and improved temperates we need to understand the problems associated with these plants.  The main problems associated with warmer weather growth are:

1.   Low leaf to stem ratio (cattle eat leaf)

2.   Higher fibre content as plants mature

3.   High level of potassium and low sodium content

4.   Low calcium and phosphorus content particularly when fresh and or dried off

5.    Variable and often, low trace mineral content + some Vitamin anomalies

6.   Low sulfur level in natives and paspalum etc giving un-favorable nitrogen to sulfur ratios

7.    Low protein and energy content except when very young.

1.     Leaf  To Stem Ratio.

Rapid summer growth of grasses changes the normal leaf to stem ratio of 70-80% leaf to as low as 20 to 30% leaf in rank summer growth, the rest being stem.  Hence, despite there being large amounts of dry matter on offer, there is only a small amount, which would normally be selected by the animal. The options to help overcome this are either short grazing rotations to maintain the highest leaf content and hence diet quality or where such intense grazing is not practical such as in extensive grazing the alternate spelling and grazing of larger areas will help maintain or improve diet quality and botanical composition.

As feed matures, the amount of leaf declines until such time as cattle are consuming stem and as an alternative some browse. As cattle start to consume browse the dung will certainly become darker due to the tannins. At this stage rate of passage, (easily seen through drier dung pads) digestibility and voluntary feed intake all decline along with animal performance.

2.       Fibre Content

The main problem with grasses is that as they mature they become progressively more fibrous and less productive.

Before going further, we need to look at fibre per se.  Fibre is most often tested for as three fractions;

Crude Fibre, Acid Detergent Fibre (ADF) and Neutral Detergent Fibre (NDF).  In terms of animal performance the ADF and NDF fractions are the most important indicators.

Higher ADF levels indicate greater lignification (increased woodiness) and resistance to breakdown.

Acid Detergent Fibre (ADF) is best considered as a measure of digestibility (as ADF increases, digestibility decreases).

Neutral Detergent Fibre (NDF) is a measure of intake i.e. higher NDF lower intake.  NDF measures bulkiness and hence determines how much an animal can fit into its stomach. It is generally assumed that cattle eat around 2.7% of body weight of Dry Matter, which is true on concentrated low fibre diets. On high fibre diets the NDF controls intake so that beef cattle often eat about 0.8 to 1% of body weight of NDF in Dry Matter see Table: 2. A 450 kg Beast on Hayed-Off pasture @ 2.7% should eat 12.15 kg when in reality they consume 5.84 kg of pasture Dry Matter due the bulkiness of the diet.

Table:1

Nutritional Value of Summer Grasses

Table:2

Calculated Dry Matter Intake Based on 2.7% Body Weight Intake Vs 1% of Body Weight Intake of NDF.

Based on 1% Bodyweight of NDF

From the above Tables you can see the value in keeping feed short and using faster rotations on the native as well as introduced grasses. The molasses or grain, which has almost no NDF value has in these circumstances a very low rate of substitution when fed at low levels but significantly raises nutrient intake and performance.

Table:3

Nutrient Requirements of Cattle.

ME, Protein,Ca & P Req’ts.

A 250 kg growing animal grazing summer grass @ flowering can consume approx 3.76 kg/day of Dry Matter (Table:2)

Using Table:1 this gives   Metaboliseable Energy                    Protein

                        3.76 X 7.8 =       29.3 Mj ME                              376g

From Table:3

Maintenance Requirement =        20 Mj ME                                240g

Then the pasture would give a small surplus for production with a slight shortage for calcium and phosphorus.

3.76kg Pasture                           29.3 Mj ME                              300g

1kg Molafos Grower                      9.5 Mj ME                              180g

Total                                             38.8 Mj ME                           480g

Maintenance Requirement =         20   Mj ME                              240g

Plus 0.5 kg / day gain                   5   Mj ME                                150g

Total Req’d for 500g/day           35   Mj ME                              390g

Because there is some walking and heat stress we would expect a weight gain of 350 to 400g/day.

This is based on simple mathematics and the principles hold from what we have seen in the field.

Legumes confuse the issue a bit as in general ruminants will consume about 15% more legume than grass despite very similar levels of NDF. This difference appears to be due to legumes having a smaller length to width ratio of the fibre leading to less time being taken to chew and break down the particles and subsequent higher rates of passage and intake.

As grass matures ADF and NDF levels increase with the following outcomes.

The diet is less digestible and hence moves more steadily through the animal restricting performance.

The diet is more bulky resulting in the animals being physically full without consuming sufficient quantity (kg’s) to enable them to perform.

There is an increased heat load on the animal from the extra heat generated in digesting this more fibrous material.

In combination, these three result in lower intake due to a less digestible more bulky diet and an added energy cost in ridding the animal of the extra heat due to digestion.

In general, adult dry animals cope better with more mature feeds than do younger or pregnant / lactating animals due to dry mature cattle having lower requirements  (hence have to eat less) and having relatively more internal space available.

3. Sodium and Potassium

Summer growing grasses are relatively low in sodium as they belong to a group of plants termed “natraphobes”, that is they don’t bring sodium out of the soil into their leaves.  Sodium is important in maintaining fluid balance and hence feed intake.

Low sodium diets result in low intakes and hence lower performance.  Salt or sodium chloride is for this reason included in most supplements to encourage animals to eat more and drink more. The exception is in areas where high salt contents are available from the water, shrubs or the soil.

Potassium levels can be excessively high in summer growing grasses, leading to the laxative effect seen in cattle grazing fresh green feed.  High Potassium intake increases the need for additional salt, calcium and magnesium in the diet.

The incidence of difficult births (dystokia), retained foetal membrane (RFM) and other diseases such as milk fever are all related to the high potassium levels in fresh green feed. Molafos Grazing Transition will help alleviate a large percentage of these issues.

The reduced efficiency of absorption of magnesium associated with high potassium / low sodium diets results in cattle becoming “flighty” or “stirry” when handled. The addition of salt and Epson Salts (magnesium sulphate) in water before transport can alleviate the above problems in transported cattle.

4. Calcium and Phosphorus

Green grass can be low in calcium but is often adequate for phosphorus for the first couple of months of growth. The exception is for cows with calves at foot or for young growing animals in which case Calcium and Phosphorus levels will be too low for optimum performance. As pasture matures and sets seed the level of phosphorus in particular declines rapidly. Because phosphorus is not only involved in bone growth but also in energy metabolism, animals need supplementation with phosphorus to perform.

Bone is 36% calcium, 17% Phosphorus and 2% Magnesium, this represents the major concentration of these minerals in an animal’s body. In terms of the skeleton as a storage depot it represents as a percentage of total body reserves 99% of calcium, 70% of phosphorus and 80% of the magnesium reserves.

The phosphorus which is in the remainder of the body is used to a large extent in energy metabolism storage and movement.  Hence animals short on phosphorus have weaker, smaller skeletons and just don’t grow (can’t use the energy).There is a feedback mechanism that reduces voluntary feed intake to match energy intake to energy use.

Wet cows don’t produce low phosphorus milk they just produce less of it, hence you get poor cows with small run-out calves. N.B 1 litre extra milk per day gives an extra 10 to 15 kg at weaning.  These same cows will most likely only calve twice every 3 years giving less weaners, which are smaller, slower growing, and more of a risk in a prolonged dry season.

In the dry animals losing weight rapidly don’t need Phosphorus because the body tissue they’re consuming has sufficient. Once you reduce or stop a weight loss with supplements you need to supplement phosphorus to get the best results. Rumen bacteria require 1g/kg of phosphorus for normal functioning and for the cold months native pasture on the native pasture grazing country is below this level. Faecal phosphorus tests would confirm the levels on the different soil types and areas.

From the map below we can quite reasonably expect to get a real benefit from supplementation with Phosphorus and protein and sulphur. Cattle supplemented with protein and phosphorus or phosphorus alone are less selective grazers (Little, 1975).  Furthermore cattle that are Phosphorus deficient will reduce their intake of pasture by up to 40% and similarly Calcium deficiency will reduce intake by as much as 34% (Minson, D.J., 1990).

Phosphorus supplemented cows will produce about 6 litres of milk per day while un-supplemented breeders produced 3.5 litres per day. (Miller, et al. 1997)

Shaded areas are where classical deficiency symptoms have been documented.

5. Trace Elements + Vitamins.

The required levels for these can be measured in milligrams, which is very small relative to their impact on animal performance.

Most of Eastern Australia is marginal for these at best and during the dry months can be regarded as low.  These minerals are involved in many enzymes within the body and will result in an improvement in weight gain.  The trace elements are cheap to provide when compared to their potential impact on animal performance and should therefore be added to supplements.  NB some vegetation types and water sources can be very high in particular trace elements and this must be taken into account on a regional basis.

Cobalt (Vitamin B12) deficient animals will develop symptoms very similar to worm infestation, with pale mucous membranes, bottle jaws and scouring. Coat colour will also suffer with coats becoming dull and more orange than red. Vitamin B12 is used to convert propionic acid to glucose in the liver hence cobalt deficient cattle are poor doers and exhibit many of the same outward signs as animals with a high worm burden.

Outside the orange shaded area where we get classical Iodine deficiency there are large areas where sub-clinical deficiency exists and where the survival of newborn animals is impaired. Plants such as clovers and brassica’s (Turnips, Canola etc) have Goitrogens which increase the need for Iodine leading to shortages in animals outside the orange shaded areas and for this reason we include Iodine in all of our supplements.

Shaded areas are where classical deficiency symptoms have been documented.

Vitamins A & E 

These Vitamins would only be an issue in cattle in a prolonged dry spell where there was no palatable / edible browse. First the transfer of Vitamin A from the mother to the foetus via the placenta is poor in cattle resulting in calves being born with very low reserves. Couple this with the Vitamin A metabolism issues caused by certain mineral imbalances and we can have deficiency problems in calves.

Vitamin A is normally supplied via colostrum to the new born with elevated levels for the first 3 days thereafter levels return to normal. Vitamin A levels in colostrum are much lower when the mother has low intake and reserves or impaired metabolism of Vitamin A. (Church et al, 1955, 1956) It is generally accepted that liver reserves of Vitamin A do not improve until dietary levels are up to 5 times requirements. (Hartman and Dryden,1965). In young cattle liver reserves can be depleted within 40 days when these animals are on a diet low in Vitamin A or with no green material available. NB as little as 30g of green material per day can stave off a problem with low Vitamin A. (Jordan, D. 2002)

Other factors, which affect Vitamin A status are:

Thyroid depression due things such as hot weather or low Iodine levels due to plants high in goitrogens or simply animals grazing pastures deficient in Iodine will decrease conversion of carotene to Vitamin A  Phosphorus deficiency in the diet appears to lower the conversion of carotene to Vitamin A. (Harris, B. 1991)

Protein deficiency in the diet affects the efficiency of utilization of Vitamin A. (Harris, B. 1991)

High dietary calcium and low Zinc levels can lead to slow release of liver Vitamin A.(Harris,B.1991) This is feasible on limestone country and as a significant amount of the artesian water supply is high in calcium, which will aggravate the low zinc and phosphorus status of the diet.

Parasite attack also appears to increase the loss of Vitamin A. (Sewell, H.B. 1993)

Infection with coccidiosis or Barbers Pole and Ostertagia could then be a factor in bringing about a problem with Vitamin A reserves.

Low Vitamin E intake from dry pasture also contributes to low Vitamin A status. (Sewell, H.B. 1993)

Vitamin B₁₂ and Cobalt status have a major impact on liver function and may along with Copper be involved in helping to maintain normal liver function and help avoid problems with Vitamin A mobilization out of the liver.

The above outlines some of the contributing factors and the simple fix is to give young cattle a supplement containing Protein, Phosphorus, Trace Elements and Vitamin A & E as well as containing an ionophore such as Bovatec to control coccidiosis. The therapeutic dose of Vitamin A required is in the order of 500,000 to 1 Million international units (i.u.) or 25,000 to 40,000  i.u. per head per day to cover any shortfall and build up a reserve. Most supplements don’t have Vitamins included as these are fragile and don’t survive long term in a liquid supplement. The best option is to have product made with the Vitamin A added and feed the supplement out inside 3 to 4 months to ensure its potency remains. NB Vitamin A and E are available for addition to the Molafos 15, 20 and 25. Molafos Grower and Backgrounder contain Vitamins A and E.

6. Nitrogen to Sulphur Ratio

Native summer and dry temperate grasses have very poor nitrogen to Sulphur ratios, often outside the desired 10:1 or less.  Ratios as high as 25:1 are common, leading to reduced microbial activity and therefore poor digestibility. Sulphur is important for rumen bacterial cells and for fungi, which break down the fibre in the animals’ diet enabling the release of energy.

The exceptions are the clovers and other legumes, which have quite good nitrogen to Sulphur ratios.

Green feed supplements must contain Sulphur to allow effective use of the available protein in the grass.

Dry season supplements of urea / non-protein nitrogen (NPN) also require additional sulphur.  As the urea adds nitrogen this widens the ratio leading to poor utilisation of the nitrogen unless the added sulphur is present. There is a significant benefit to be realized from feeding not just urea, but adding sulphur as well as the above-mentioned nutrients.  In short the sulphur makes the urea work.

The importance of minerals to NPN utilisation is best shown by Coombe, Christian and Holgate:

The Effect of Urea on the utilisation of ground pelleted roughage by penned sheep:

Mineral Supplements - All Treatments Urea ± Minerals

S = Sulphur        P =  Phosphorus

The above shows sheep being fed 7.5 grams of urea per day with 4% protein wheat straw. Without sulphur they all lost weight and when given sulphur they then picked up. When sulphur was again taken off the group represented by the top line they again started to lose weight.

 7.  Protein and Energy

When grasses are short and fresh protein and energy levels are high and animals will usually perform.  This period of adequate protein and energy will only last for up to three months and generally follows a downward path after about six weeks of growth.  Energy is always the first limiting nutrient after water.

Once pasture protein falls below 7% there is a rapid fall off in feed intake signaling a need to commence protein supplementation. In as short a time as 8 weeks after a break in the season pasture protein levels can fall below the 7% necessary to maintain rumen microbial numbers for this reason most green feed supplements contain a source of protein.

Table: 4 Composition of Feed - Dry Matter Basis

In some extensive grazing situations where survival is the main goal energy is generally only fed as a supplement to the rumen microbes to improve digestion. Molasses based supplements in the southern beef producers situation are a different proposition as the aim is production and to maintain growth and fertility over the year through body condition in cows and heifers in particular.

Protein plus energy is fed to improve the efficiency of utilisation of urea / non-protein nitrogen. Urea + salt or urea + water supplement systems have an efficiency of utilisation of 22% vs a balanced supplement with an efficiency rating of 52%.  From this we see a balanced supplement is over twice the value / effectiveness of urea /salt supplements. Molafos pasture supplements contain protein plus energy as well as major and trace minerals and in some cases vitamins and Medications/ fermentation modifiers such as Bovatec, Flavomycin and Monensin.

Feeding a balanced supplement can lift intake of pastures by up to 40%, which can turn a weight loss into a weight gain, it will also give the breeders a lift in milk production with the obvious flow-on to the quality and weights of calves at weaning. So what we have with a better supplement brew is a herd that will eat more of the pasture and in effect take in more energy, protein and minerals, which are available to the animal for production.

BREEDERS.

The real issue being faced in most years is to wean early to maintain body condition on the breeders. Below are a couple of simple checks, which can be applied at station level to gauge what is the likely effect on breeders of delaying action.

The system used for Body Condition Scoring (BCS) which is the international standard follows the original sale description of cattle as distinct from the fat score system now in use which is not validated in research or used internationally.

Table:5 Description of Body Condition Score and Fat Scores

Body Condition Score                    Description                                 Fat Score

1                                             Weak and Emaciated                             1

2                                              Poor                                                    1.5

3                                              Backward Store                                     2

4                                              Store                                                   2.5

5                                              Strong Store                                         3

6                                              Forward Store                                     3.5

7                                              Fat                                                       4

8                                              Prime                                                  4.5

9                                              Obese                                                  5

Fat Score 1   Body Condition Score 1.

Fat Score 1.5 Body Condition 2.

Fat Score 1.5 Body Condition 2.

Fat Score 2 Body Condition 3. 

Fat Score 2.5 Body Condition 4. 

Fat Score 2.5 Body Condition 4.

Fat Score 2.5 Body Condition 4.

Fat Score 3 Body Condition 5.

Fat Score 3 Body Condition 5.

Fat Score 3.5 Body Condition 6.

Fat Score 3.5 Body Condition 6.

Fat Score 3.5 Body Condition 6.

Fat Score 4 Body Condition 7.

Fat Score 4.5 Body Condition 8.

Fat Score 4.5 Body Condition 8.

Fat Score 4.5 Body Condition 8.

Fat Score 5 Body Condition 9.

Kunkle and Sand. (2003)

The effect of body condition score on the time taken for cows to rebreed after calving can be seen in the following Table:

Table: 6 Effect of Breeder Condition on Days Empty and Subsequent Fertility.

Fat Score    BCS.       Time to Re-Breed.      Conception Rate %       % Pregnant

2                   3                   89 days                              70                          43

2.5                4                   80 days                              80                           61

3                   5                   59 days                              94                           86

3.5                6                   62 days                            100                           93

4                   7                   31 days                            100

(Houghton, et. al., 1990)         (Rae, et. al., 1993)

The above Table shows that once breeders slip back in condition the time taken to rebreed blows out and this can have significant impact on the chance of these animals getting back in calf particularly in controlled breeding. Put simply we won’t be getting a calf inside 12 months. The Fat Score 2 breeders take almost 3 months to re-breed and conception rates and confirmed pregnancies are also depressed giving no chance of a 12 month calving interval.

The value of effective supplements and body condition on fertility are represented in the graph below:

In the above graph the effect of body condition on conception rate in a three month controlled mating is shown. The implications are here for situations where you have an extended mating, to have a large number of late calves if cow condition is allowed to slip e.g. to drop from a Fat Score of 4 to 3 would give a reduction in the number of early calves of 15 to 20%. Usually, a late calf is followed up with the breeder deciding to have a holiday the next year.

Assuming breeders have a lifespan in the herd of 10 years i.e. culled at 10 to11 years of age, then a breeder à will have a maximum of 8 calves and

• each holiday she has = 1 / 8 or 12.5% reduction in weaning
• add to this the 8 to 14% (say 10%) loss that occurs between conception and weaning and we have the following breeder performance
• 1 holiday = 77.5% Weaning Rate
• 2 holidays = 65% Weaning Rate
• 3 holidays = 52.5% Weaning Rate
• 4 holidays = 40% Weaning Rate

The only way to avoid this occurring is to maintain fat scores at calving and joining of 3 + (5+ BCS) for mature breeders and of 4 (7 BCS) for heifers. Regular scoring of breeders at key times will allow an assessment to be made on management of the herd.

HEIFERS.

The real issue is to get the weaners off breeders before they pull them down in condition, this is particularly important with heifers on their 1^st calf to ensure we get a second calf the next year and so on.

Table:7 Body Condition Score in heifers affects Calf Immunity, Colostrum production and time taken for the calf to stand after birth (Odde, 1989).

                                                                  Heifer Body Condition Score.

Body Condition Score (BCS)                  2          3          4         5         6        7

Fat Score                                            1.5         2         2.5       3        3.5      4

Time for calf to stand (Minutes)              --         60         64       43       35       --

Colostrum Production (Litres)              0.75      1.53      1.11     1.41      --        --

Immunoglobulin levels were lower in calves from low body condition score Heifers.     The aim for replacement heifer body weight should be to achieve 70% of mature cow weight at least 2 months prior to joining and to then join Maiden Heifers 3 to 4 weeks before mature cows. It is best to have heifers calve at one body condition score (Half a Fat Score) higher @ 6 or 7(Fat Score3.5) vs 5 or 6(Fat Score 3) for mature breeders and at 85% of mature body weight.

The effect of body condition score on the time taken for the newborn calf to stand and take its first drink has implications for survival, with increased losses due to desertion and or predators. By maintaining body condition at over 5 you have stronger calves down for less time and stronger mothers with fewer problems from predators.

Table:8 Effect of Body Condition Score (BCS) on Fertility in First Calf Heifers

Number of Days After Joining                          20                  40                  60

Fat Score               BCS                                       Cumulative % Pregnant

2.5                           4                                     27                  43                 56

3.0                           5                                     35                  65                 80

3.5                           6                                     47                  90                 96

 (Spitzer, et. al., 1995)

This Table shows the value of Fat Score or BCS in heifers and re-affirms the necessity of weaning on breeder condition. With a weaning age of 4 months heifers will have calves at foot when they are required to be getting pregnant, hence the recommendation to join early in the first year. The second requirement is to monitor body condition score to ensure weaning is timely and supplementation has a chance to help maintain calving pattern.

WEANERS.

For the weaners the program is as follows:

• 120kg to 180kg live weight feed Molafos Grower which has the grain and protein meal and Bovatec @ 0.6 to 1.5 kg/ head/day fed out in open troughs.

N.B. We’re trying to not only get protein and minerals into these guys but also the extra energy to get them through without any check in growth and subsequent reduction in ability to grow muscle and bone when they try to compensate. i.e. they’ll grow out normally when they hit good feed or if put into a feedlot.  The addition of Bovatec will reduce the risk of coccidiosis and increase efficiency of digestion. Calves Rumens are stimulated to develop due to the level Volatile Fatty Acids in particular Propionic Acid in the rumen. The key to knowing that they are really starting to go ahead is to see them chewing their cud and they really start to brighten up.

• 180kg to 250kg live weight Molafos Grower @ 1.0 to 2.0 kg /head/ day on poor feed or  Molafos 15 on better feed. If pasture quality is good with faecal protein tests showing 8% or better weaners will do on Molafos 15 with Bovatec. Bovatec increases the efficiency of the Rumen and ultimately gives either an extra 80 to 100g per day weight gain or the same reduction in weight loss. The bonus with Bovatec in weaners is the reduction in the incidence of coccidiosis and the increased Propionic acid levels in the Rumen, which help stimulate rumen development.

Table:9 The effects of poor weaning management are illustrated in the trial findings of the Beef CRC

Poor Nutrition (less 300g/day weight gain) prior to 250kg live weight leads to: -

• Long term reduction in ability to grow both muscle and bone.
• Increased baseline toughness in the meat.

The potential for compensatory gain is also impaired

Eg.                                   % of Adult Size                    % Compensation

Check                         @ 69%   (350kg)                                   100%

                                      40%    (250kg)                                    93%

                                      30%  (< 250kg)                                  76%

The table above shows the effect of restriction in live weight gain in young cattle. A growth check prior to 250 kg live weight will result in long-term restriction in ability to grow and results in an increase in fat as a proportion of the extra gain during periods when compensatory gain is possible.

In short animals restricted early in life are generally smaller in frame, less well muscled and prone to producing an over-fat carcass.

ME, Protein,Ca & P Req’ts.

For Comparison

                                                    Mj ME       Protein             Calcium           Phos.

1kg  Molafos Grower                    9.5 Mj        180g                 5.5g                6.0g

1kg Molafos 15                            9.4 Mj        150g                  6.0g                3.5g

To use the Table read the value for the animal eg a 300kg weaner:-

Maintenance = No Wt Gain           23Mj          275g                11g                  9g

To grow at 300g / day               +  9Mj           90g                  3.6g                 3g

Total Required                      =  32Mj           365g                15 g               12 g

So for weaners which are currently not growing you would need to feed 1.0kg of Molafos Grower  per head per day to gain @ 300g/day

This is above the minimum of 250g per day to avoid permanent effects on the performance of cattle.

Simple Observations.

In the simple scheme of things the following are a few basic tips:

• Wean on breeder condition.
• 1 condition score is between 45 and 55 kg live weight.
• 1 Fat Score is between 90 and 110 kg live weight.
• A big weaner will pull a well conditioned cow down at around 1kg /day = 0.5 of a Fat Score (1 condition score) in 6 to 7 weeks, on the same feed a thin cow BCS 4 or Fat Score 2.5, will be losing close to 2 kg/day or 1 Fat Score (2 condition scores) a month to feed her calf. The Table shows the cost to an animal of producing just 6 litres of milk, given that 1kg of body weight on a breeder in strong condition = 30 Mj of Energy.

If you have dry empty cattle that are maintaining body weight then you can assume that a wet cow on the same feed will be losing around 1kg of body weight per day.

1 Body Condition Score = 45kg Live Weight = Leaving a weaner on a cow giving 6 to 8 litres of milk for an extra 6 weeks.

Given that 1 kg Body Fat = 30 Mj ME  = the energy cost of 6 Litres.

• Watch the dry and or empty cows for an indication of feed quality. If they’re holding body weight then the above will happen. If they’re gaining weight then take this off the above weight loss to give an indication of how fast breeders are slipping.
•  Knowing the Fat Score / Body Condition Score breeders need to calve in enables a quick calculation to be made knowing that the last 3 months of pregnancy a cow has to have enough energy to put on half a kg per day just to grow the calf. Based on this it’s very difficult to put weight on a cow in this period so any improvement in body weight needs to happen after weaning and prior to the last 3 months of pregnancy.

Then you will need to allow time to put condition back on breeders, if for example you wean at 6 months then a breeder will on average be 3 months pregnant. We know it’s hard to put weight on cows in the last trimester of pregnancy so we really only have the second trimester of pregnancy to put the weight on. This gives us 90 to 110 days to work with.

Example: - Not the ideal situation.

Wean in March Breeders in Fat Score 2 (Body Condition Score 3).

Start to calve in August to October and have breeders at Fat Score 3 to 3.5 (Body Condition Score 5 or 6.)

It is difficult to get weight on cows from end of May till calving due top cold and generally poor pasture growth in the colder months i.e. last 3 months of pregnancy.

Then breeders need to gain 1 Fat Score (2 Body Condition Scores) (90-110kg) in 3 months

= 90kg/100 days = 900 g / head / day to make it work(Highly unlikely in the winter)

If the breeder Fat Score was 2.5 (condition score 4) at weaning then the gain becomes 450 g/head/day, which is achievable in late Summer to Autumn.

•  By keeping an eye on the length and diameter of the fibre in the dung we can visually assess how well our pasture is travelling. The fibre in dung pads should be about 1 cm long and as thick as hair fibre. Any longer or thicker and it indicates cattle are eating a greater proportion of stem hence intake, digestibility and rate of passage through the animal will be declining along with performance.
•  Small weaners need extra help to survive and grow. Molafos Grower or a grain mix is one way of giving them a hand and stimulating the development of the rumen. Molafos 15 and dry feed don’t do the job on weaners under 180 kg live weight. This sized weaner needs to have Molafos Grower to go ahead.

Based on the above calculations the following three supplements are recommended.

In the above table the trace mineral levels are explained as follows.

The Organic trace minerals used are much more available than the inorganic sulphate forms. Organic Copper is 2.5 times the availability of copper sulphate

Organic Zinc is 2.25 times the availability of zinc sulphate

Organic Manganese is around 60 X the availability of Manganese Sulphate.

References:

Church, D.C. et al (1971) In Digestive Physiology and Nutrition of Ruminants. Volume 2 – Nutrition.

Coombe, Christian and Holgate:

Harris,B. (1991).Vitamin Needs of Dairy Cattle. Edis.ifas.ufl.edu/DS153

Hartman, A.M., and Dryden, L.P. (1965).  In Fundamentals of Dairy Chemistry.

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