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South Durban basin of South Africa has witnessed tremendous urban, industrial expansion and mass tourism impacts exerting significant pressure over marine environments. 43 sediment samples from 7 different beaches (Bluff beach; Ansteys beach; Brighton beach; Cutting beach; Isipingo beach; Tiger Rocks beach; Amanzimtoti beach) were analyzed for acid leachable metals (ALMs) Fe, Mg, Mn, Cr, Cu, Mo, Ni, Co, Pb, Cd, Zn and Hg. The metal concentrations found in all the beaches were higher than the background reference values (avg. in μg g − 1 ) for Cr (223–352), Cu (27.67–42.10), Mo (3.11–4.70), Ni (93–118), Co (45.52–52.44), Zn (31.26–57.01) and Hg (1.13–2.36) suggesting the influence of industrial effluents and harbor activities in this region. Calculated geochemical indexes revealed that extreme contamination of Cr and Hg in all the beach sediments and high Cr and Ni levels poses adverse biological effects. [ABSTRACT FROM AUTHOR]

Abstract: Zulu sheep are indigenous to KwaZulu-Natal, South Africa and provide food security for traditional farmers. Through traditional selection they adapted to the climatic conditions of KwaZulu-Natal. The goal of this study was to use genetic diversity and existing phenotypic data for the breed to argue exploitation opportunities and conservation needs. Three populations (52 Zulu sheep) were included and random amplified polymorphic DNA profiles were used to provide genetic diversity data. A similarity matrix consisting of 2744 RAPD bands (∼46.0% polymorphic) was constructed. Complete linkage analysis indicated lowest genetic similarity (88.96%) within the Makhathini population, greatest (94.83%) in the UNIZULU population and intermediate (91.38%) in the KwaMthethwa population. Similar phenotypic similarity was observed for UNIZULU and Makhathini populations (58.75% and 54.63%, respectively). Complete linkage dendrograms for genetic and linear body measurement data also show that UNIZULU and Makhathini populations are more closely related to each other than to the KwaMthethwa. This study demonstrated usefulness of RAPD profiling for genetic data for Zulu sheep. It also demonstrated that phenotypic and genetic data could be sensibly combined into a single database for this sheep breed. This is important since such information will be critical for decisions regarding Zulu sheep breed exploitation and conservation. [Copyright &y& Elsevier]

Abstract: Data on linear body measurements (LBM) of 403 sheep collected in three areas of KwaZulu-Natal were utilized to develop a prediction equation for live body weight of Zulu sheep. Data were collected on live weight (LW), heart girth (HG), wither height (WH) and scrotum circumference (SC) on sheep of all ages. The age of sheep was estimated by dentition. The analysis of variance showed that age and sex were important factors contributing to variation in LW of Zulu sheep. Phenotypic correlation coefficients and regression equations of LW on HG, WH and SC were computed within different age groups (milk set of teeth, one pair, two pairs and the three and four pairs of incisors). Low correlation coefficients (r =0.21–0.48) between LW, HG and WH were found among the pregnant ewes. The relationship between LBM and LW was stronger (r =0.66–0.86) for males than among females (r =0.42–0.75). The cubic polynomial of HG was the best fit (R 2 =0.76) for the live weight prediction of young sheep with milk set of teeth. The combination of HG and WH produced the best fit for the two tooth and above males and non-pregnant females. The LW prediction equations for pregnant females were not reliable (R 2 =0.05–0.26). The SC was more precise (R 2 =0.61–0.80) when estimating the live weight of young males (<15–22-month-old) than of the older rams (R 2 =0.23–0.56). It was concluded that LW of Zulu sheep can be reasonably estimated using the HG and WH. A table could be constructed for the farmers to estimate the LW of their animals. [Copyright &y& Elsevier]

Abstract: Information regarding morphology of indigenous sheep in South Africa is scant, and even where data exist it is rarely presented using standardised methodologies. Principal component analysis (PCA) was applied to 13 body measurements in order to provide an objective description of the body shape and size of 1665 Zulu sheep, obtained from rural communities of KwaZulu Natal. Data was analysed separate for young (no permanent incisors) and adult sheep (≥2 pairs of permanent incisors). On average mature males measured higher than mature ewes in most morphometric traits. The correlation coefficients between different body measurements in young sheep were all significant except for correlation between ear length and tail length whilst in adult sheep 79 out of 96 combinations showed significant correlation. Body weight and heart girth had the highest correlations in both age groups. Ear length and tail length related combinations had lower correlation coefficients in both age groups. The PCA of morphometric traits extracted two components with a total variance of 66.85% in young sheep and four components in adult sheep which explained a total variance of 62.13%. The first factor (PC1) in each case had high loadings for variables relating to body size, whilst PC2 had high association with traits reflecting body shape. The PC3 had high factor loadings for head length and head width, and thus defined head size. Tail length, ear length and whither height on the other hand contributed least towards total variation. The use of principal components was more appropriate than the use of original correlated variables in predicting body weight of Zulu sheep. PCA was able to identify traits with greater variability, these can be improved with greater success in breeding programmes and also the number of variables was reduced to give a concise picture of morphological structure (body size and shape) of a Zulu sheep. These components can as well be used in predicting body weight of Zulu sheep. [Copyright &y& Elsevier]