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Forum Home > Sanga Composites > Beef Production in the tropics - Johann Zietsman

Andrew Hope
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The tropics are the last frontier for beef production in the world. The potential for environmental degradation or an extremely high level of sustainable production are both very high. Cattle, in the hands of man, can be a tool of exploitation and destruction or a tool of progress and environmental stability. The outcome depends on how cattle are bred and managed. Cattle have to be bred and managed in order to fulfil a dual role. Firstly, they must be bred and managed for a high relative intake that will result in efficient grass conversion. Secondly, they have to be managed in such a manner that they improve the land on which they depend.

Conventional stud breeding under artificial conditions (nutrition; total parasite control using poisons; selective grazing) with the use of inappropriate selection criteria (absolute measures of growth; no genetically discerned fertility) that, in some instances, are measured accurately (BLUP derived EPDs) is the biggest obstacle to sustainable beef production. A completely new model of beef production based on common sense and natural processes needs to be adopted. For such a model to be applicable to the tropics it has to be founded in the tropics. It is essential for the cattle producing areas of tropical Latin America and northern Australia to employ technology originating in tropical Africa. This applies to both genetics and management. The following are the salient points:

1. The African Zebu and Sanga groups of cattle are the survivors of a poor nutritional status (corralling; draught) and an extremely high incidence of disease and parasites. This has led to genotypes with a high relative intake (relatively small frame; tropical adaptation; disease and parasite resistance; aggressive foraging ability) resulting in efficient utilisation of high fibre grasses and inherently good body condition. Although there is individual variation, the African breeds are also sexually early maturing (before the intervention of modern breeding methods), inherently good mothers, easy calving, handler friendly with a high meat; bone ratio. The African breeds, in combination with each other as well as with other breeds, will greatly improve the profitability of beef production in the tropics and even some temperate areas.

2. A high proportion of African breed blood is essential. This will impart a high degree of inherently good body condition to cattle that have to survive and produce under the constraints of the tropics.

3. Survival of the fittest and not the prettiest must apply. There is no positive role for show judges and breed inspectors. The role of man is to “read” nature correctly and accelerate the process of natural selection. The first step is to devise genetically discerning selection criteria in regard to efficiency of grass conversion (relative intake), practical fertility (inherent body condition and hormonal balance) and cow efficiency (calving ease, mothering ability and optimum milk). In addition, cattle must have a high meat: bone ratio and easy-care attributes. Current selection criteria based on absolute growth (weaning weight; daily growth rate; time constant weight) and nutritionally determined fertility must be scrapped in favour of relative growth (maturity rate) and genetically determined fertility (inherent body condition and hormonal balance).

4. In contrast to current practice and belief, where only lip-service is paid to genetically determined fertility, practical fertility (hormonal balance and body condition) is highly heritable. The challenge is to devise genetically discernible selection criteria. It is now possible to rank cows of similar phenotypic (observed / measured) fertility in terms of genetically determined fertility. This, together with other criteria, allows accurate bull selection in terms of practical fertility. Assuming a high selection differential (AI), the result is extremely fast improvement in genetic herd fertility. A nucleus herd selected on this basis in Zambia is maintaining a calving rate in excess of 92% relative to 75% for other herds run under the same conditions.

5. The potentially productive tropical savannas and temperate grasslands of Africa are the product of an interaction between large herds of severe grazers and predators. In modern management cattle have replaced buffalo and wildebeest and man has to play the role of the predator in bringing about a healthy ecosystem. In other words time-controlled high animal impact and severe (non-selective) grazing has to be implemented on a ranch scale. In tropical America jungle is being replaced by grasses from Africa. Such a man-made ecosystem will only be stable and ranching sustainable if , in addition to productive grasses, leguminous forbs and deep-rooted trees are established and the whole system managed appropriately through time-controlled high animal impact and severe grazing.

6. The ruminant is an amazing animal given the fact that it can convert material that is basically useless to man into a product that is part of a high quality diet. In order to do this it requires a healthy rumen microbe population that is dependent on certain nutrients. On high fibre diets (lignified grass) it is essential to feed the rumen microbes (mainly protein) to speed up digestion and throughput of energy. This increases the efficiency of grass utilisation and conversion.

7. In the seasonal rainfall tropics the nutrient requirements of cattle have to be synchronised with naturally available nutrition. If this is done with body condition at calving in mind, there is no major ranching region where a calving / breeding season longer than 42 days is required. The advantages of this are numerous:

• A high calving rate. At least 80 – 90% of suckling cows should be cycling before the start of the breeding season.

• A high proportion of 14/15 month heifers should be sexually mature in order to be bred for 2-year-calving. This is uncommon, but possible, in the tropics.

• The phenotypic variation between individuals can be measured with greater genetic discernment. This, together with a high degree of selection differentiation (AI), allows for much greater genetic change.

• Protein and mineral supplementation, where necessary, will be far more effective.

By utilising African breeds and African technology cattle production in the tropics can become ecologically and economically sustainable. The potential increase in productivity is two to three times. This increase in productivity, measured in conventional terms, is equivalent to cows producing twins and triplets.

Johann Zietsman


Sanga cattle, bridging the genetic gap between Bos Taurus and Bos Indicus breeds.

February 29, 2012 at 1:08 PM Flag Quote & Reply

Posts: 6

More terrific info from Johann!

March 1, 2012 at 9:52 AM Flag Quote & Reply

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