Die Voorspellingsgeldigheid van die ESSI lees- en speltoets vir nie-moedertaal primêreskoolleerders

Graad 5 tot 7 leerders afkomstig vanuit drie Afrikataalsprekende groepe in die Vrystaat, naamlik Sesotho, isiXhosa, en Setswana, is by die studie ingesluit. Voorspellingsgeldigheid is ondersoek deur die leerders se tellings op die lees- en speltoets van die ESSI met hulle akademiese prestasie te korreleer. Hierdie korrelasies is vir die drie Afrikataalsprekers afsonderlik ondersoek. In al die gevalle is koëffisiënte van medium tot groot effekgroottes gevind. Verder het die resultate aangedui dat geen beduidende verskille in die gemiddelde lees- of speltellings vir die onderskeie taalgroepe vir elk van die onderskeie grade voorgekom het nie. Ten opsigte van die leerders se prestasie op die ESSI-toets is wel geslagsverskille gevind. Waar beduidende verskille voorgekom het, het die dogters beduidende hoër gemiddeldes as die seuns behaal.Kernwoorde: ESSI Lees- en Speltoets, voorspellingsgeldigheid, niemoedertaalsprekers en akademiese prestasieEnglish AbstractGrade 5 to 7 learners descended from three African language groups in the Free State, namely Sesotho, isiXhosa, and Setswana, were included in the study. Predictive validity was investigated by correlating the learners’ scores in the ESSI Reading and Spelling Test with their academic achievement. These correlations were done for the three African language groups separately, and in all the instances, coefficients with medium to large effect sizes were found. The results further indicated that the average achievement of learners of various language groups in a particular grade in the reading and spelling tests did not differ significantly from one another. It was also found that the two genders were indeed inclined to perform differently in the ESSI tests. Where significant differences were found, the girls obtained significantly higher average scores than the boys did.Keywords: ESSI Reading and Spelling Test, predictive validity, non-mother tongue speakers and academic achievemen

Ovule, seed and seedling characters in Acharia (Achariaceae) with evidence of myrmecochory in the family

An investigation of mature seed structure in Guthriea capensis and ovule-to-seed development in Acharia tragodes indicate that the two species are herbaceous myrmecochores with similar adaptations for seed dispersal and germination. The development and structure of the modified seed tissues, namely a sarcotestal elaiosome, a fringe layer in the mesotesta, endotestal-exotegmic mechanical layers and a chalazal seed lid are described. Additional embryological similarities between the two taxa include, amongst others, sessile ovules, distally lobed outer integuments, zigzag micropyle canals formed by both integuments, bisporic Allium Type embryo sacs, suspensorless embryos belonging to the Penaea Variation of the Asterad Type, and small embryos in the mature seed. In Acharia intraseminal embryo growth occurs before radicle emergence, germination is epigeal and seedlings belong to the Macaranga Type

Heritabilities of reproductive traits in a beef cattle herd using multitrait analysis

(South African J of Animal Science, 2000, 30, Supplement 1: 140-141

Heritability estimates derived from threshold analyses for reproduction and stayability traits in a beef cattle herd

The object of this study was to estimate heritabilities and sire breeding values for stayability and reproductive traits in a composite multibreed beef cattle herd using a threshold model. A GFCAT set of programmes was used to analyse reproductive data. Heritabilities and product-moment correlations between predicted breeding values for stayability at 36, 48, 60, 72 and 84 months of age, calving success and longevity were estimated. The estimated heritabilities on the underlying scale for these traits were 0.06, 0.10, 0.06, 0.03, 0.11, 0.03 and 0.08 respectively. Product-moment correlations between breeding values for stayability traits were low. The highest correlation of 0.22 was obtained between the ages of 36 and 48 months. Heritability estimates and correlations between traits appear to be of such a low magnitude that selection for these characteristics would result in limited genetic improvement, and also indicate that sires had little influence on the stayability, longevity or calving success of their daughters. (South African Journal of Animal Science, 2001, 31(1): 25-32

The potential to control Haemonchus contortus in indigenous South African goats with copper oxide wire particles

The high prevalence of resistance of Haemonchus contortus to all major anthelmintic groups has prompted investigations into alternative control methods in South Africa, including the use of copper oxide wire particle (COWP) boluses. To assess the efficacy of COWP against H. contortus in indigenous South African goats, 18 male faecal egg-count-negative goats were each given ca.1200 infective larvae of H. contortus three times per week during weeks 1 and 2 of the experiment. These animals made up an “established” infection group (ESTGRP). At the start of week 7, six goats were each given a 2-g COWP bolus orally; six goats received a 4-g COWP bolus each and six animals were not treated. A further 20 goats constituted a “developing” infection group (DEVGRP). At the beginning of week 1, seven of the DEVGRP goats were given a 2-g COWP bolus each; seven goats were treated with a 4-g COWP bolus each and no bolus was given to a further six animals. During weeks 1–6, each of these DEVGRP goats was given ca. 400 H. contortus larvae three times per week. All 38 goats were euthanized for worm recovery from the abomasa and small intestines in week 11. In the ESTGRP, the 2-g and 4-g COWP boluses reduced the worm burdens by 95% and 93%, respectively compared to controls (mean burden ± standard deviation, SD: 23 ± 33, 30 ± 56 and 442 ± 518 worms, P = 0.02). However, in the DEVGRP goats, both the 2-g and 4-g COWP treatments were ineffective in reducing the worm burdens relative to the controls (mean burdens ± SD: 1102 ± 841, 649 ± 855, 1051 ± 661 worms, P = 0.16). Mean liver copper levels did not differ between the ESTGRP goats treated with 2-g COWP, 4-g COWP or no COWP (mean ± standard error of the mean, SEM, in ppm: 93.7 ± 8.3; 101.5 ± 8.3; 71.8 ± 8.3, P = 0.07) nor did they differ between the DEVGRP goats (mean ± SEM, in ppm: 74.1 ± 9.1; 75.4 ± 9.1; 74.9 ± 10.0, P > 0.99). The copper values were considered adequate, but not high, for goats. The COWP boluses have the potential to be used in the place of conventional anthelmintics for the control of established H. contortus infections in indigenous South African goats, but their use as part of an integrated approach to control H. contortus in the field must be fully investigated

Persistence of the efficacy of copper oxide wire particles against Haemonchus contortus in grazing South African goats

A study was conducted to examine the duration of anthelmintic effect of copper oxide wire particles (COWP) in grazing goats, as data for the persistence of efficacy of COWP in this host species is limited. Forty-eight indigenous male goats were infected naturally by grazing them on Haemonchus contortus-infected pasture. When the faecal egg count (FEC) in the goats was 3179 ± 540 eggs per gram of faeces (mean ± standard error), half the animals were treated with 4 g COWP (day 0; mean live weight = 25.5 ± 0.8 kg). Eight treated (COWP) and eight non-treated (CONTROL) goats were removed from the pasture on each of days 7, 28 and 56, maintained for 27 or 29 days in concrete pens and then humanely slaughtered for nematode recovery. Mean liver copper levels were in the high range in the goats removed from pasture at day 7 (treated: 191 ± 19.7 ppm; untreated: 120 ± 19.7 ppm; P = 0.022), but had dropped to normal levels at days 28 and 56. The mean H. contortus burdens of the treated versus the non-treated goats were, respectively, 184 ± 48 and 645 ± 152 for the goats removed from pasture at day 7 (71% reduction; P = 0.004), 207 ± 42 and 331 ± 156 at day 28 (37% reduction; P = 0.945) and 336 ± 89 and 225 ± 53 at day 56 (−49% reduction; P = 0.665). Weekly monitoring of FECs after treatment until slaughter indicated that the COWP-treated goats had lower FECs than the controls, the treatment main effect being significant at days 7, 28 and 56 (P < 0.01). The day main effect and the treatment × day interaction were only significant for the goats removed from pasture at day 28 (P ≤ 0.001). Packed cell volumes increased during the course of the experiment (day, P < 0.001), but the treatment main effect was significant only for the goats removed from pasture at day 28 (CONTROL 28 d, 28.65 ± 0.52% < COWP 28 d, 31.31 ± 0.52%; P < 0.001). No differences in live weight between groups were considered to be of any practical significance. The study indicated that persistence of efficacy of COWP is limited in goats, extending at most to 28 days after treatment. However, repeated COWP administration at three-month intervals may be safe, given that liver copper levels return to normal two to three months after COWP treatment

A method for establishing taxonomic research priorities in a megadiverse country

A coordinated strategy for biosystematics research that addresses the needs of end-users can improve the relevance and impact of research products. The basic types of information that taxonomists provide, common to all organisms, are the names, descriptions, and a mechanism for identifying components of biodiversity, and associated data such as distribution information. This information is provided through taxonomic research. A biosystematics research strategy has been developed in South Africa to focus on the main gaps in taxonomic knowledge. A prioritisation process has been developed and applied to plants, but can potentially be used for all organisms. The methodology for development of the taxonomic priorities to formulate a research strategy is described. Determining priorities for taxonomic research and development of the strategy will facilitate bridging the gaps among compilers, users and implementers of taxonomic information, and streamline the taxonomy-conservation impediment.Botanical Education Trust.http://www.mapress.com/phytotaxahb201

History and drivers of plant taxonomy in South Africa

The development of plant taxonomy in South Africa from about 1600 to 2015 is reviewed, with emphasis on the main driving factors that have influenced the research direction, techniques used, and choice of taxonomic research topic. In addition, key personalities and important historical events are highlighted. The early scientific interest in the flora of South Africa and, by implication, its taxonomy was initially driven by curiosity. Exploration of plants for economic purposes especially for medicinal use and later, agriculture, drove the scientific development of botany and formed the foundation of formal botany in the country. Establishment of botanical gardens and herbaria influenced botanical research, in particular the field of taxonomy. Technological advances lead to increased modernisation of taxonomy as new sources of information derived from other fields of botany were incorporated into taxonomic research. Funding priorities and availability of financial resources influence the taxonomic research that is conducted, and international initiatives that impact on priorities in biodiversity science have further impact on taxonomy. At present the predominant culture of taxonomy is directed towards electronic dissemination of taxonomic information, leading to increased accessibility and connectivity. Strategic planning of plant taxonomy in South Africa has become more formal as relevance and impact of research products increasingly need to be justified with respect to the financial costs of conducting taxonomic research.The University of Pretoria is thanked for financial support.http://www.mapress.com/j/pt/am2016Plant Scienc

Proposal to conserve the family name Asphodelaceae (Spermatophyta : Magnoliidae : Asparagales)

Asphodelaceae c omprises a round 12 genera a nd about 1060 species (Africa, Mediterranean basin, Arabian Peninsula, west and central Europe, Madagascar, Central Asia, Australia, New Zealand), Hemerocallidaceae some 19 genera with about 117 species (tropical and temperate Eurasia, Australia, New Zealand, several Pacific islands, Madagascar, western South America, southern Africa), while Xanthorrhoeaceae s.str. has one genus with some 28 species (restricted to Australia, including Tasmania). The Angiosperm Phylogeny Group (APG II in Bot. J. Linn. Soc. 141: 399–436. 2003 & APG III in 161: 105–121. 2009) combine these three families into Xanthorrhoeaceae s.l., although APG II provided the option to also use Asphodelaceae and Hemerocallidaceae, under the system of socalled “bracketed families”. APG III, however, did away with this option, thus leaving Xanthorrhoeaceae as the only choice.http://www.botanik.univie.ac.at/iapt/s_taxon.phpam201

The correct name of Aloe plicatilis, the fan aloe, in the genus Kumara (Asphodelaceae: Alooideae), again

The combination Kumara plicatilis (L.) Klopper & Gideon F.Sm. recently published for the fan aloe [Aloe plicatilis (L.) Burm.f.], is a synonym of Kumara plicatilis (L.) G.D.Rowley, the latter having priority due to earlier valid publication.Die kürzlich für die "fan aloe" [Aloe plicatilis (L.) Burm. f.] publizierte Kombination Kumara plicatilis (L.) Klopper & Gideon F.Sm. ist ein Synonym von Kumara plicatilis (L.) G.D.Rowley, welche Prioriät aufgrund der gültigen früheren Publikation hat.http://www.bcss.org.uk/journal.htmlam201