Kommunikasiekunde in Suid-Afrika: die begin, die hede en uitdagings vir die toekoms

Communication science in South Africa: the beginnings, the present and challenges for the future This article is based on the Gert Pienaar Commemorative Lec-ture given by the author of this article on 27 August 2009 at the North-West University, Potchefstroom. The late Professor Gert Pienaar founded communication science (then Press Science) in South Africa, fifty years ago. Apart from acknowledging his contribution, the purpose of the lecture and of this article is to briefly outline the main research paradigms which have guided South African mass communication research the past fifty years, namely the positivist (or managerial) paradigm and the critical paradigm. It is argued that normative questions about the role and functions of the media in society underlie these paradigms. Against the background of new paradigms such as the postmodern and postcolonial paradigms (of which the basic tenets are also outlined) the applicability and relevance of old normative media theory in a new society and in a new media landscape (briefly described) are questioned and the Western prejudice of “old” normative theory is highlighted. With this in mind, four research areas for future South African mass com-munication research are emphasised, namely fundamental new media research, development communication research from an African perspective, communications policy research, and the indigenisation of mass communication theory

PROMOTING THE PURCHASING OF PERFORMANCE TESTED DORPER RAMS: THE ROLE OF AGRICULTURAL EXTENSION

Published ArticleThe sale price of 868 Dorper rams sold between 2004 and 2013 were compared with their measured performances. The independent variables (Selection, Weaning Index, Wean direct, Wean maternal, Post wean, Breeding value for number of lambs weaned (GLS), Relative economic value (REV), Selection Index percentage (SI%), Scrotal deviation (SD), Mean Lamb Index (MLI) and Ewe productivity Index (EPI) were used to predict the dependent variable (sale price of the Dorper rams) from 2004 to 2013. Factors with the most significant influence in order of importance were selection (stud or commercial), SI% and REV. It is evident that rams with better performance figures fetched higher prices. Although buyers did consider breeding values when buying rams none of it consistently contributed to sale price. It appears that buyers rather responded on SI%, a performance parameter familiar to them which was displayed in the sale catalogue from the beginning of the project. In an extension approach performance data must form the base for convincing breeders and farmers to move towards more scientific breeding methods, combining visual evaluation with measured performance at all Dorper sales. A unified effort by research, extension and the Breeders’ Society may address the problem best

PROMOTING THE PURCHASING OF PERFORMANCE TESTED DORPER RAMS: THE ROLE OF AGRICULTURAL EXTENSION

Published ArticleThe sale price of 868 Dorper rams sold between 2004 and 2013 were compared with their measured performances. The independent variables (Selection, Weaning Index, Wean direct, Wean maternal, Post wean, Breeding value for number of lambs weaned (GLS), Relative economic value (REV), Selection Index percentage (SI%), Scrotal deviation (SD), Mean Lamb Index (MLI) and Ewe productivity Index (EPI) were used to predict the dependent variable (sale price of the Dorper rams) from 2004 to 2013. Factors with the most significant influence in order of importance were selection (stud or commercial), SI% and REV. It is evident that rams with better performance figures fetched higher prices. Although buyers did consider breeding values when buying rams none of it consistently contributed to sale price. It appears that buyers rather responded on SI%, a performance parameter familiar to them which was displayed in the sale catalogue from the beginning of the project. In an extension approach performance data must form the base for convincing breeders and farmers to move towards more scientific breeding methods, combining visual evaluation with measured performance at all Dorper sales. A unified effort by research, extension and the Breeders’ Society may address the problem best

Score and hide-thickness, together with tick burden and body condition score, in four cattle breeds in the South-eastern Free State province of South Africa

Published ArticleA study was conducted to determine the differences between four breeds in respect of coat score, hide-thickness, tick burden and body condition score. The study was comprised of 40 heifers - 10 of each breed, namely Afrikaner, Braford, Charolais and Drakensberger. A subjective system of coat scoring, ranging from extremely short to very woolly, was used. Body condition score was measured subjectively, with 1 being emaciated and 9 being obese. Hide-thickness (in mm) and tick count were also determined. Between August 2007 and early March 2008, measurements were carried out on the same 10 animals of each breed, with highly significant differences in body condition score, hide-thickness and tick count being observed between the breeds in all instances. Coat scores differed significantly between breeds in the earlier and latter stages of the study becoming less significant midway through. A significant difference in body condition score within breeds was also found, while hide-thickness did not differ significantly within breeds

A SURVEY OF LICK SUPPLEMENTATION AND MANAGEMENT PRACTICES OF COMMERCIAL BEEF FARMERS IN THE ZASTRON DISTRICT

Published ArticleA study was conducted to determine the supplementation and management practices of commercial beef farmers. 48 commercial farmers from the Zastron district were selected for this study out of a prospective of 60 farmers that were bona fide commercial farmers and members of Free State Agriculture. The farmers reported the following calving percentage ranges: one farmer (2.1%) between 50 and 59%, three farmers (6.3%) between 60 and 69%, 19 farmers between 70 and 79%, 22 farmers between 80 and 89% and three farmers between 90 and 99%. Preventative vaccination was common practice as only one farmer did not vaccinate any of his cattle (n = 48). The provision of supplements seemed to be general practice (100%, n = 48) in the district as all the farmers gave some form of supplementation to their cattle. Only 22.9% (n = 11) of the farmers provided supplements according to the production status of the animals and the main reason for not doing so is that 37.8% (n = 14) of the respondents believed that it complicated management and 18.9% (n = 7) thought it not necessary. It is believed that a lack of understanding of the function of supplements by some of the farmers in the district could be the cause of what could be considered as insufficient supplementation by animal nutritionists

Effect of different levels of supplementation after weaning on beef heifer development

The purpose of the study was to identify a cost-effective supplementation regimen to rear replacement heifers on transitional Cymbopogon-Themeda veld. A total of 120 Drakensberger heifers aged 6 - 7 months were randomly allocated to three supplementary treatment groups from 2011 - 2014. A three-phase supplementation programme was used while the production year was divided into three periods, namely summer (wet season) (approximately mid-December to March), winter (early dry season) (April to July), and late winter (late dry season) (August to approximately mid-December). The late winter treatments consisted of three levels of supplemental crude protein (CP), a percentage of protein derived from non-protein nitrogen (NPN) and metabolizable energy (ME), namely T1: 306 g CP/kg (47.4% NPN) + ME 7.4 MJ/kg; T2: 329 g CP/kg (70.72% NPN) + ME 6.89 MJ/kg; and T3: 475 g CP/kg (95.86% NPN) + ME 2.4 MJ/kg. In summer, T1 was supplemented with 164 g CP/kg (7% NPN) + ME 9 MJ/kg + 13 g P/kg; T2 with Voermol Superfos with 150 g CP/kg (13.6% NPN), ME 0 MJ/kg, and 50 g P/kg; T3: 0 g CP/kg, ME 0 MJ/kg, and 60 g P/kg. The traits were nutrient intake, supplement cost, mean bodyweight, weight gains/losses and mean BCS. The study concluded that feeding replacement heifers to traditional bodyweight increased development costs without improving production sufficiently. Veld that is in good condition together with a mineral (60 g P/kg) supplement in the wet season and a protein and mineral supplement (96% NPN) in the dry season gives the highest economic return. Keywords: beef heifers, post wean, supplementatio

Production and profitability of a beef herd on transitional Cymbopogon-Themeda veld receiving three levels of lick supplementation

The purpose of the study was to investigate the effects of three levels of lick supplementation on the production and reproduction of cows grazing transitional Cymbopogon-Themeda veld. The study was conducted over three years (2011–2014). A total of 150 Drakensberger cows were randomly allocated to three supplementary treatment groups. These supplementation formulations are available commercially and are typical of levels used under farming conditions. In summer Treatment 1 (T1) consisted of a supplement containing 50 g phosphate (P)/kg and 150 g crude protein (CP)/kg. T2 and T3 both consisted of supplements containing 60 g P/kg and 0 g CP/kg. In winter, T1 consisted of a supplement containing 367 g CP/kg, 77.5% non-protein nitrogen (NPN) and metabolizable energy (ME) content of 5.25 MJ/kg. T2 had 466 g CP/kg, 88.7% NPN and a ME content of 4.4 MJ/kg. T3 had 475 g CP/kg, 95.9% NPN and an ME content of 2.4 MJ/kg. Traits were calf birth weight, 100-day and weaning weights of calves, cow weight at weaning, inter-calving period (ICP), conception rate and body condition score (BCS) of cows. Calf birth weight was affected by supplementation treatment only in year 3 and 100-day weight in year 2. However, weaning weight and reproductive performance were not influenced by treatment. It was concluded that the level of supplementation of each treatment group enabled the cows to operate within their target weight range; however, it was more profitable to use the T3 supplementation option.Keywords: Cymbopogon-Themeda veld, cows, performanc

THE EFFECTS OF SWEDISH MASSAGE ON PERFORMANCE HORSES IN SOUTH AFRICA

Published ArticleA somatologist receives skilled training in different alternative therapies, as well as the well-being of the entire body. Massages on equine athletes, may not only broaden the horse-loving somatologist's specialising field, but might improve the horses' performance and well-being by using massages, as a warm up/cool down routine. The objective of the research was to investigate the effects of Swedish massage on the performance ability of competitive horses. Swedish massages were applied on thirty horses, from various breeds, representing three disciplines namely Dressage (n=10), Endurance (n=10) and Saddlebred (n=10). Each horse received ten massage treatments over a period of five weeks. The horses' performance improvement was measured to analyse their flexibility, muscle injury and relaxation before and after the massages. Although the blood parameters for muscle injury, aspartate aminotransferase (AST) and creatine kinase (CK) did not respond to the Swedish massage, the results indicated that the treatments resulted in significant (P<0.05) lower heart rates, as well as improved flexibility of the horses' necks, backs and shoulders. Human athletes benefit from Swedish massage to enhance their performance ability. Equine athletes have similar ailments as humans and then the possibility exists that equine athletes may benefit as human athletes. This then can be aligned with the somatologists scope of practice and broaden their working field

The profitability and production of a beef herd on transitional Cymbopogon- Themeda veld, receiving three different levels of lick supplementation - Preliminary results

Published ArticleThe importance of containing costs through the optimal utilization of feed emphasizes the need to optimize, rather than maximize, the rate of reproduction. It is, however, unknown which lick supplementation regimen, provided to an extensive beef herd on mixed veld, could bring about the most profitable and efficient farming enterprise. The aim of the study was thus to determine what lick supplementation regime would be most profitable in an extensive beef production system maintained on transitional Cymbopogon-Themeda veld. The different lick supplementation regimens offered differed in crude protein (CP) content, percentage non-degradable protein (NDP), metabolisable energy (ME) content, and recommended daily intake. A herd of Drakensberger cows and heifers was divided into three treatment groups (Treatment A, Treatment B and Treatment C), with 70 animals (n = 70) per treatment group. The CP, NDP, ME content of the licks provided in Treatment A were higher than those provided in Treatment B and C, while the CP, NDP, ME content of the licks provided in Treatment B were higher than those provided to Treatment C, but lower than those provided to Treatment A. The first two years’ (2011 - 2012 and 2012 - 2013) preliminary results indicate no significant differences in parameters that affect cow herd performance (weaning weight, cow herd pregnancy rate, intercalving period) between treatments. However, substantial cost differences in the lick supplied between treatments was recorded; thus, affecting profitability. Significant differences between treatments in the pregnancy rates of the first-calf heifers was recorded in the second year, and indicated that providing protein in a drought during summer to first calf heifers may increase the calving rate and hence profitability

Protection of Grapevine Pruning Wounds against Eutypa lata by Biological and Chemical Methods

Eutypa dieback, caused by the fungus Eutypa lata, is a serious disease of grapevines that infects mainly through pruningwounds. The aim of this study was to evaluate the in vitro efficacy of fungicides from various chemical groups againstE. lata, as well as the in vivo efficacy of the most effective fungicides and selected bacterial and fungal antagonists ofE. lata, in grapevine pruning wound protection trials. In vitro studies revealed that flusilazole, tebuconazole, benomyl,fenarimol and myclobutanil were the most effective fungicides to inhibit mycelial growth of E. lata. Two field trialswere conducted, one subjected to artificial inoculation and the second to natural infection only. In the first, benomyl,flusilazole and commercially available Trichoderma harzianum-containing products and an experimental Bacillussubtilis strain were applied to fresh pruning wounds. Two Cabernet Sauvignon vineyards were pruned in August2001 and 2002 and immediately treated and inoculated with a spore suspension of E. lata one day later. Isolationswere made from the treated pruning wounds after 12 months to assess the effectiveness of the treatments. Thefungicides benomyl and flusilazole were the most effective treatments, although the Trichoderma treatments T77 andTrichoseal spray caused a significant reduction in E. lata infection. In a second trial, pruning wounds of CabernetSauvignon, Sauvignon blanc, Red Globe and Bonheur were treated with the Trichoderma products Vinevax (=Trichoseal spray) and Eco77 (= T77) in August 2005 and 2006, subjected to natural infection only and evaluatedafter seven months. Vinevax and Eco77 not only reduced E. lata, but they also reduced the incidence of othergrapevine trunk disease pathogens