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Genesis

Extracts from 'The Genesis of the Bonsmara' by Jan Bonsma*

The main problem of livestock production in the tropics and sub-tropics, the world over, was what became known as the tropical degeneration syndrome amongst the Bos taurus breeds of cattle. The British beef breeds, namely the Shorthorn, Hereford, Angus and to a lesser extent, Sussex and Red Poll, did not thrive under the sub-tropical conditions of the ranching areas of South Africa.

In the northern parts of South Africa, the altitude is 900m, average annual temperature 20 degrees Centigrade (reaching 40 in summer) and the annual rainfall is 450mm.

Before 1940 it was thought that tropical degeneration of the British breeds was caused by malnutrition. The protein content of natural pastures in the Southern hemisphere is low, dropping to critically low levels during late summer and early winter.

Because poor nutrition was considered to be the cause of tropical degeneration, a large-scale nutritional experiment was launched at the Messina Livestock Research Station in 1937, using a large group of heifers of different British beef breeds.

This brought Bonsma to the realization that malnutrition was not the culprit. Amongst the heifers were individuals that thrived appreciably better than others.

Careful observation proved that those, which showed the least climatic stress, thrived best. Those animals that showed signs of stress on hot days had a very high respiratory rate, they panted, their tongues hung out and dribbled profusely.

Because Bonsma wanted to MEASURE every aspect of the livestock that he worked with, he made numerous observations on his experimental animals. These included regular weighing, 14 different body measurements, body temperature, pulse- and respiratory rates, hair count per square centimeter and tick counts. Hair diameters were measured and complete hair coats of different types of cattle were shorn off, weighed and put through a felting machine.

These elaborate tests proved beyond doubt that the hide and coat of cattle played a tremendous role in the process of heat dissipation, which is of the utmost importance for the animal to maintain its thermal equilibrium in the environment.

Animals that suffer from hyperthermia have increased respiratory and pulse rates with concomitant metabolic, physiological and endocrinological disturbances.

Animals with a respiratory type of body conformation, a wide forehead and convex facial profile are much better adapted to the tropics and sub-tropics than those with a digestive type of body conformation and a dished forehead and profile.

It has been convincingly shown in several critical experiments, and it is only logical, that the larger the surface area of the nasal sinuses, the greater is the surface area available for evaporative cooling during panting.

It would seem reasonable, therefore, to assume that cattle with broad heads and a convex profile ('Roman nose'), would be able to cool their brain tissue more effectively than those with narrow heads and a concave profile. Afrikaner cattle are extremely well adapted to hot and arid conditions. That they also have relatively large, broad heads with a convex Roman profile appears to be of great importance in their physiological adaptation, and not merely a fancy point dreamed up by breeders.

Only after the climatological data on the various types of cattle were submitted to the late Professor A. M. Bosman, could Bonsma convince him that the proportion of blood in the new breed to be established, should be the opposite of the Santa Gertrudis, namely, 5/8 Afrikaner and 3/8 British beef breed (the Santa Gertrudis consisted of 5/8 British beef breed and 3/8 Bos indicus). The South African research showed conclusively that as soon as the British beef breed content of the Afrikaner/Bos taurus cross went beyond 50%, signs of distress were encountered on hot days.

At this early stage of the breed creation project it was not possible to decide which of the British beef breeds would give the best results when cross-bred to Afrikaner cows.

After many criss-cross matings, the 5/8 Afrikaner, 3/16 Hereford and 3/16 Shorthorn animals seemed the most satisfactory and became the new breed now known as the Bonsmara.

Thanks to Bonsmaras unique method of scale photography, the Bonsmara is the only breed in the world that can boast a pictorial genealogy from the very beginning of the breeding work until the new breed was established.

It is also unique in that every mating was based on scientific data, where the concept MAN MUST MEASURE was always taken into consideration.

* Jan Bonsma: LIVESTOCK PRODUCTION, A GLOBAL APPROACH, Tafelberg Publishers Ltd, 1980, p. 90-110.

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