The selenium status of grazing herbivores in different regions of Southern Africa

(South African J of Animal Science, 2000, 30, Supplement 1: 145-146

Geographical distribution of the selenium status of herbivores in South Africa

Available information on the selenium (Se) status of grazing herbivores in South Africa is reviewed and collated in the form of a geographical distribution map. Marginal to acute Se deficiencies have been reported to occur in the Midlands region and in mountainous areas of the KwaZulu-Natal province and in the southern coastal region of the Western Cape province. These areas receive a high annual rainfall and the soils are predominantly acid. The Se status of livestock in the highland sourveld areas of the Gauteng, northern Free State and Mpumalanga provinces is varied. Selenium intake appears to be adequate in most areas although localised cases of deficiencies occur. Substantial air and water pollution occurs in some of these areas, and the presence of Se antagonists could increase the incidence of Se deficiency in future. Limited data indicates that vegetation in the arid regions of South Africa provides Se sufficient to meet the requirements of grazing herbivores. Subterranean water from a number of locations contains Se at concentrations higher than the norm for safe drinking water, the impact of which has not yet been established. There are large areas of South Africa for which little or no information on the Se status of grazing animals exist, and further investigations are required. (South African Journal of Animal Science, 2001, 31(1): 1-8

A glance at achievements of SASAS and animal scientists in southern Africa over more than 50 years

With the congress theme of ‘Golden Innovations for Sustainable Animal Agriculture’, it would be opportune to look not only at innovations with present and future potential, but at those ‘golden innovations’ that have been achieved and established over more than five decades. Many of these innovations still form the basis of many aspects of present-day sustainable animal agriculture in southern Africa. This brief review covers three areas, namely the history of the South African Society for Animal Science (SASAS), achievements of animal scientists, mainly in the earlier years of the Society, and the coming of age of professionalism in the animal science profession. The South African Society of Animal Production (SASAP) was founded on 28 April 1961 in Pretoria. The name was later changed to the South African Society for Animal Science. The theme of the first congress of SASAP was ‘Efficiency in Production’, a theme that is still relevant. In 1971 the South African Journal of Animal Science (SAJAS) was initiated, and by 2017 the 47th volume has been published. A large amount of knowledge that is applicable to local conditions has accumulated and should be drawn upon to avoid ‘reinventing the wheel’. In the 1950s to 1970s, Professor Jan Bonsma developed the concept of functional efficiency of cattle and principles that focused on adaptability and sustainability. Extensive research was conducted on the feeding of urea and phosphorus to grazing livestock, leading to the practice of urea-containing rumen-stimulating winter supplementation of ruminants. South Africa was considered a world leader in the field of supplementary feeding practices. South Africa has a proud history in the discipline of animal genetics and the practical application of breeding principles to enhance livestock productivity, and is in the forefront with studies on the genomics of livestock in southern Africa. SASAS was instrumental in establishing the professional status of animal scientists in South Africa. The vision is that an animal scientist should be identified as the expert in his/her field and the best qualified person to advise on matters such as animal breeding, nutrition and general management of livestock. SASAS council also acts as a mouthpiece for and custodian of animal scientists. The society protects the interests of animal scientists, is pro-active in promoting animal science, and acts as a watchdog over the professional activities of members.Keywords: Animal production, history, professional animal scientis

The influence of molybdenum and sulphur on sheep receiving high levels of copper and broiler litter in their rations

No Abstrac

The chemical composition of leaves from indigenous fodder trees in South Africa

(South African J of Animal Science, 2000, 30, Supplement 1: 72-73

Performance responses of lambs of various ages to Italian ryegrass (Lolium multiflorum) fertilized with various levels of nitrogen

Italian ryegrass (Lolium multiflorum cv. Midmar) is often fertilized with high levels of nitrogen (N) in order to ensure maximum dry matter (DM) yields. This practice also increases the N content of herbage. This study was conducted to determine whether differences in the nitrogen (N) content of Italian ryegrass would have an effect on the performance of South African Mutton Merino lambs. Fertilizer levels of 100, 200, 400, 600 or 800 kg N/ha were applied to the pastures in order to produce herbage containing varying concentrations of N. Nitrogen fertilization increased the total N and nitrate-N in the plant material and decreased non-structural carbohydrate concentrations. An increase in rumen ammonia-N concentration with increasing pasture N concentration was observed in twelve and four-month-old lambs. A quadratic relationship was found to exist between the N content of ryegrass and DM intake for twelve-month-old lambs, and a negative linear relationship was observed for four-month-old lambs. A quadratic relationship was observed between the N content of ryegrass and average daily gain for lambs of both age groups. The equations derived in this study illustrate the potentially negative effects of high concentrations of N and nitrate-N in Italian ryegrass on intake and growth rate of lambs. South African Journal of Animal Science, Vol 31, Issue 3, Oct – Dec (2001): pp. 142-148Key Words Average daily gain, Dry matter intake, Italian ryegrass, Lambs, Nitrogen, Nitrate-nitroge

Effect of ionophores and selenium supplementation on the composition of long-chain fatty acid in carcass fat of steers

(South African J of Animal Science, 2000, 30, Supplement 1: 131-133

Trace mineral status of the African Buffalo (Syncerus caffer) in the Kruger National Park

(South African J of Animal Science, 2000, 30, Supplement 1: 38-39

Minerals and nitrogen in poultry manure

No Abstrac

The effect of whole cottonseed and processing of canola on the milk production and composition of first lactation Holstein heifers

(South African J of Animal Science, 2000, 30, Supplement 1: 40-41