Stocking rate and by implication, grass conversion efficiency, is the most important factor and by far the most important __determinant__ of profitability and return on capital and will improve veld condition and eliminate selective grazing. Stocking rate can be drastically increased via time-controlled non-selective grazing and high animal impact.

Toet 123

Fertility, as determined by inherent body condition and hormonal balance, is by far the most important __traits__ required by cattle.

Carcase quality is of minor importance in relation to overall ranch profitability.

Non-selective grazing, without a doubt, has a negative effect on body condition. This, in turn, negatively affects cow fertility which is the most important trait determining profit. These contradictions have to be regarded as //challenges//, rather than problems, and addressed accordingly – See 5. Management Measures.

Not many ranchers appreciate the high marginal reaction that accrues from extra labour and/or technology. This would definitely solve the challenge in regard to frequent daily moves and body condition.

Utilising smaller camps without adding any animal numbers to your farm does not increase your stocking rate. You will still have the same number of animals on your farm. You are just utilising your grass better. This, however, will probably result in having too much grass after one year and result in you having to burn it if you are in the sour-veldt region. All this is to ensure that you have any form of nutrition for the animals.

Buying in animals can be done, but adaption takes time, and this will not necessarily address your fertility problem.

Building your herd organically, and correcting genetics so that the mother animals can give you a calve from the age of two years and then annually after that, and wean that calve between 42% and 50% of her body weight, will be more profitable in the long run.

Selling a cow only needs to be done because of age and for cash flow reasons. Alternatively her calves can be used to increase the stocking rate. There are, however, certain criteria that the cow must fulfil for you to use her bull calves for your herd improvement, and weaning weight is not one of them.

As far as the profit drivers of beef farming is concerned, stocking rate is the highest profit driver, then fertility and then growth. Both stocking rate and growth have a negative influence on fertility. It is always a balance between these three components to become profitable. It does not help to have a high stocking rate and a low conception rate, nor having a high conception rate but not enough animals. The problem with weaning weight is that they are no indication of profitability either.

There is no consensus on the definition of grazing/browsing capacity (the productivity of grazeable/browsable portion of a homogeneous unit of vegetation expressed as the area of land required to maintain a single large stock unit over an extended number of years without deterioration to vegetation or soil) in literature and is therefore a habitat characteristic and must be distinguished from stocking rate (area of land the farmer allots to each large stock unit).

Grazing capacity calculation methods:

· Rainfall method of Coe, Cummings & Phillipson (1976)

· Combined veld condition and rainfall method of Danckwerts (1989)

· The herbaceous phytomass method of Moore & Odendaal (1987)

Case study: Rhino ranch, 40km East of Ellisras, rainfall 372mm, 2066ha. Method 2 and Method 3 yielding 0.057 and 0.052 L.S.U/ha or 118 and 107 L.S.U. respectively. This is 50% of the long term agricultural grazer stocking rate recommendation of 0.10 L.S.U/ha or 207 L.S.U.

RCS has developed a system of assessing carrying capacity based on SDH per 100mm rainfall to account for this variation. Rainfall must be included to account for the seasonal variability and changes in carrying capacity. A common characteristic of regenerative grazing is the proactive changes made to stocking rate as seasonal conditions change actual carrying capacity so ground cover and plant and soil health is always maintained regardless of the seasonal conditions. We refer to what one LSU eats in one day as one Stock Day (SD). That can then be calculated on a per hectare basis to give us Stock Days per Hectare (SDH).

Drought can be defined as ‘not having stock feed when you expect to have feed’.

The grazing chart is a monitoring tool that measures the grass yield taken out of paddocks (SDH), as well as rolling 12-month SDH/100mm. This is used to provide a leading indicator for required changes in stocking rate by comparing to your benchmark carrying capacity calculated based on the ability of that land type and water cycle to convert rainfall into useable fodder.

· Long Term Carrying Capacity = 4 ha/LSU

· 365 days ÷ 4 ha/LSU = 91.25 stockdays/ha (SDH)

· Annual Rainfall = 625 mm/year

· 91.25 SDH ÷ 625 mm = 0.146 SDH/mm

· 0.146 SDH/mm × 100 = 14.6 SDH/100mm

Or

· Long Term Carrying Capacity = 10 ha/LSU

· 365 days ÷ 10 ha/LSU = 36.5 stockdays/ha (SDH)

· Annual Rainfall = 300 mm/year

· 300 SDH ÷ 300 mm = 0.1 SDH/mm

· 0.1 SDH/mm × 100 = 10 SDH/100mm

I am becoming more aware of the paradigm “grass managers” have in regard to overgrazing (insufficient time for complete plant recovery). The above graph illustrates the negative relationship between quality and recovery time in fast growth environments (particularly the seasonally humid / humid tropics and sub-tropics).

The differences between the two environments is based on humidity (non-brittle) vs low annual humidity (brittle). In brittle environments like above the problem is feed – poorly managed pastures turn to dirt. In non-brittle environments it takes an act of God to show dirt (Roundup or continuous ploughing) because rainfall and humidity are high allowing for regrowth of plants. Brittle environments are EXTREMELY fragile – in short order you can create a desert in them. It is almost impossible to do so in a non-brittle environment because regrowth is so quick. Fragile short roots get enough water to persist whereas in brittle environments, without a root system, will die off without sufficient water.

The most satisfying environment to work with is the brittle environments because with the addition of cattle feet in high densities, there will be an explosion of growth because of those feet and the addition of rain. Cattle feet, urine and dung are also crucial for leftover (good or bad) plant material because it will oxidize vs breakdown because of lack of humidity. High densities of cattle feet knock the plant material to the ground where breakdown can occur and soil can be fed and covered from the suns purification and intense heat.

Brittle grazing approach requires short periodic grazing, accelerating decomposition and break down of soil caps.

Humidity is the primary requirement for microbial function.

Roots are where the plant’s food reserves are stored – these reserves are used by the plant for regrowth after it has been grazed down. If a plant has been grazed extremely short, it extracts more reserves to produce leaves and regrowth is slower. As more leaves form, food reserves are restored in the roots.

If the regrowth is utilised before reserves are re-channelled to the roots, even more, reserves are extracted. If this happens continuously, the root mass and plant become smaller and grass production declines. Palatable and preferred species will become extinct due to overgrazing, the carrying capacity will decline and livestock production will become unsustainable. Plant cover will dwindle, water run-off will increase, water infiltration will decrease, and the soil structure will weaken and the biology will change.

The stems are highly lignified and the plants have likely moved protein into the seeds. The rumen microbes will benefit from extra degradable protein. Digesting more of the fibre provide more energy to the cows and improve the body condition of the cows.

Plants with strong root systems and broad leaves will generally be more efficient at photosynthesis. Such plants will be the result of fertile and well aerated soil as well as appropriate time-control. This is a scenario that can be created by the prudent use of the hoofs and mouths of cattle.

Andrè Voison first described that all plants follow a sigmoid growth curve and the phases of growth across that curve can be split into three stages. The first stage (Phase I) is characterised by short growing grass and a corresponding short root system. Generally, plants will come into Phase I after a non-growing period or by being overgrazed. Plants in Phase I have a small green leaf area therefore photosynthesis is restricted and energy for growth is supplied by root zones. Overgrazing at this time will severely tax the plant and continued grazing will cause it to eventually die.

The second stage (Phase II) is characterised by an abundance of green leaf area and an actively growing plant. Both leaf areas and root zones are expanding with energy being supplied from the sun through photosynthesis. This is the prime time for grazing the plant and short graze periods will significantly extend this phase. Plant production is at its optimum as is animal production. The goal of regenerative grazing is to manage the plants for this phase with the strategic use of grazing animals.

The third stage (Phase III) is where the plant elongates and leaf area is replaced by lignification. Plant cell walls become increasingly thicker and photosynthesis is significantly reduced as plants stop growing and energy for growth is no longer needed. Plant roots are no longer important as the growth stage has finished and root zones become much reduced. Grazing animals halve their intake of Phase III plants because their stomach microbiology takes twice as long to process lignified grass. The combination of reduced intake and a 50% loss in nutritional value means Phase III plants have a very low production capacity. All efforts must be made to reduce this phase as much as possible.

Black or gray grasses in my opinion are only those oxidizing for lack of being eaten by cattle but in your case they were eaten. Annual grasses sometimes turn gray at the end of growth when they lack rain.

As usual, the nutritive value decreases with plant age whereas the fibre content increases. Between 35 and 65 days, a 10 day interval resulted in a percentage reduction of 1.3, 1.2 and 0.4% for in vitro DM, OM digestibility and crude protein respectively, and an increase of 0.6, 0.7 and 0.3% for NDF, ADF and lignin, respectively (Camarao et al., 1983). Similarly, the crude protein of koronivia hay decreased from 9.6 to 4.9% DM and the in vitro DM digestibility decreased from 68% to 61% between 30 and 86 days (Rodriguez-Romero et al., 2004).

Season also affects the nutritive value. In the Colombian savannah, 6-week old foliage had a 5.2-8.5% crude protein content in the rainy season and 3.3-9.3% in the dry season; in vitro DM digestibility was 59-66% and 51-67% respectively (Cook et al., 2005). Some much lower values have been reported from Brazil (Marajo Island), with crude protein of 3.5% and 4.8% DM in the dry and rainy seasons respectively, corresponding in both cases to an in vitro OM digestibility of 34% (Cardoso et al., 1997). The overall decrease in nutritive value is partly explained by the diminution of the leaf:stem ratio, since the in vitro DM digestibilities for the leaves and stems (considered separately) are generally stable throughout the year (Moura et al., 2002). An application of N fertilizer increases the crude protein content (Botrel et al., 1990).

The following table shows the variation of crude protein and NDF according to plant age (Feedipedia, 2011).

Table 1. Influence of stage of growth on the composition of Brachiaria humidicola:

Stage Number of days of regrowth Crude protein % DM NDF % DM Number of samples (CP/NDF)

Vegetative 20-35 9.9 ± 2.6 69.4 ± 4.5 9/5

Bloom 35-85 6.3 ± 2.1 75.7 ± 3.4 13/10

Mature >100 5.1 ± 2.1 80.1 ± 3.9 8/6

Grasses are commonly called C3 (high octane) and C4 (low octane) meaning the amount of carbon molecules each has.

C3 grasses are cool season grasses - start early (can handle cold), are lush and sweet, high in sugar and protein but lack lignin (carbon) and commonly cause the runs (no fibre and high protein) and if rains come in the fall season can have a flush of growth in the fall as well.

C4 grasses are considered warm season grasses - start later when temperatures rise, are consumed quickly early in the season, but lignify quickly, are higher in fat and do wonders under snow pressure (lignin or the extra carbon gives a stronger stem) and due to the carbon and lignin are consumed less once they become mature/rank due to lack of protein and too high of fibre making a cow feel full longer, lacking protein to feed rumen microbes making fibre sit and overall consumption decreases which causes weight loss. Tropical areas have more C4 grasses. Temperate regions if a short growing season will have little or no C4 grasses due to not enough time to mature and seed out.

Johann Zietsman monitored his grass species over several years. In 1995, he had 86% unpalatable species, 9.5% semi-palatable and 4.5% palatable. One year later he had 46% unpalatable, 28% semi-palatable and 26% palatable.

The Outcome

%%Non-Selective UHDG grazing will lead to a decline in individual animal performance. This needs to be mitigated by management (breeding and grazing) practices - Management Measures (5).