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We document changes in rangeland during a prolonged drought in the arid Karoo. Rangeland in this arid region is species-rich and dominated by a mixture of long-lived succulent and non-succulent shrubs. Ranching has led to the domination of vegetation by less palatable species, and resting does little to restore diversity because most species are long-lived. Between 2015 and 2020, a combination of rising temperatures and low rainfall reduced vegetation cover and grazing potential throughout the Karoo. Mortality varied among species, habitat and with predrought rangeland condition, but appeared independent of size class. Growth form was not a good predictor of drought survival, although vegetation dominated by non-succulent shrub species before the drought was dominated by a succulent shrub species toward the end of the drought. Dieback was greater on deep soil than in drainage lines and on stony rises. Historically degraded landscapes lost relatively more vegetation cover and grazing capacity than areas protected from grazing. By reducing dominant, long-lived, non-forage shrub species, drought appears to be changing the composition of the vegetation to a state that may have higher grazing potential, particularly if livestock numbers are reduced and reseeding is carried out during the recovery period. [ABSTRACT FROM AUTHOR]

The persistent spread of shrublands is a global phenomenon observed across semiarid grassland-shrubland boundaries. Observations in South Africa, however, have detected a contrasting trend of increasing grass cover across the transition between the Nama-Karoo and Grassland Biomes over the last few decades. A west-to-east gradient of increasing mean annual rainfall, and underlying geology, controls the natural transition of Karoo dwarf shrublands to semiarid grasslands. The availability of historical vegetation surveys and landscape photographs, weather, and livestock census records, made it possible to assess the nature, extent, and drivers of vegetation change across this biome transition. Rainfall has been generally higher over the last four decades compared to the years prior to the original surveys. This, together with a reduction in livestock numbers, is the main driver of the westward expansion by ∼100 km of perennial grasses, and a general increase in dwarf shrub and total vegetation cover. Rangeland condition, as indexed by estimates of grazing capacity, has improved significantly. Despite a structural shift towards grassland-dominance, the original species complement has persisted. The rainfall-driven increase in grass fuel loads in the region, however, places these rangelands at risk of becoming altered by increasing fire frequency. [ABSTRACT FROM AUTHOR]

• Minimal differences between the same Aloidendron dichotomum populations after five years. • Tracking individuals does not make a difference to general demographic findings. • Healthy long-lived species do not only display inverse J-shaped size-class. The findings of the first four Aloidendron dichotomum population surveys in 2015 that form part of a long-term monitoring initiative started by the South African Environmental Observation Network at Meerkat National Park were compared with the findings of a second survey in the same populations in 2021. Aloidendron dichotomum is a keystone species and was previously suggested as a climate change indicator species therefore understanding its population dynamics is important. A general population density and mortality survey, as well as a detailed demographic survey were repeated in August 2021 using the same methods that were used in 2015. The surveys were conducted in the same populations but not of exactly the same individuals. The aim of this study was to compare the findings of the 2021 surveys with the findings of the 2015 surveys in order to assess whether it is crucial to survey exactly the same individuals within a population or not. Live: dead ratios varied considerably across the populations between the surveys conducted in 2015 (range: 17 to 35 per ha) and in 2021 (range: 6 to 28 per ha). For each population the size class distribution (SCD) types did not differ significantly between 2015 and 2021. Populations had zero permutation indices for basal diameter for the two surveyed years suggesting that the populations are monotonically declining and therefore the populations are stable. However, two permutation indices for height were not zero. The presence of leaf fungi and scale during the two surveys was generally low while the presence of lichen remained similar between survey years. There was more damage to leaves and stems in 2021. Our conclusion is that the general demographic findings for the 2015 and 2021 surveys were similar so it is not necessary to survey exactly the same individuals within a population to determine the general demography of a population. However, marking and measuring exactly the same individuals could provide valuable insights onto the finer nuances of population demographics and dynamics in this species. [ABSTRACT FROM AUTHOR]

Background and objectives: Long-term studies of woody plants in South Africa are scarce. This study, initiated in the late 1970s, therefore aids understanding of vegetation dynamics in the southern Kalahari by investigating woody vegetation change at and away from a watering point. Methods: At three sites, all woody individuals were counted by species in plots 0.5 or 1 ha in size. Seedlings were noted separately from the >0.2 m group of individuals. Results: Vachellia erioloba and shrub density decreased over time whereas dwarf shrub species' numbers fluctuated markedly. Additionally, no increase in density of known bush encroaching species (e.g. Grewia flava, Rhigozum trichotomum and Senegalia mellifera) was found in this large conservation area. Discussion and conclusion: The changes in density of the woody species seem to point to the importance of particular rainfall patterns or sequences of events over different years that are responsible for these changes in the southern Kalahari, and the evident lack of bush encroachment in this conservation area supports the notion that bush encroachment in arid savannas is driven primarily by land-use practices and not by elevated carbon dioxide levels that are sometimes provided as cause for encroachment. [ABSTRACT FROM AUTHOR]

This case report describes a rare case of nodal low grade serous pelvic neoplasia. Together with histological correlation, it illustrates previously undocumented cytomorphological features and also discusses important differential diagnosis and potential pitfalls for misdiagnosis. [ABSTRACT FROM AUTHOR]

The iconic succulent tree, Aloidendron dichotomum , is found throughout the arid and semi-arid parts of South Africa and Namibia. It has been suggested as a climate change indicator species with long-term monitoring of populations initiated by various institutions in order to improve understanding of its population dynamics and main climate drivers. This proposed monitoring protocol attempts to combine various methodologies already used in order to standardise on field data collection procedures. In order to illustrate the value of the data collected this paper compares baseline demographic data recorded for 12 populations across the Northern Cape (South Africa). Live and dead tree densities were highly variable across populations. Size class distribution (SCD) analysis using height classes and basal diameter classes resulted in different population curve types depending on the variable plotted emphasising the importance of variable choice. Comparison of the midpoint of the basal diameter classes and the natural logarithm of density of individuals per class indicated different linear regression slopes for the Kokerboomkloof population and eight other populations and in one instance, the Kokerboomkloof intercept value differed. In all populations, the calculated centroid value was smaller than the median indicating growing populations. The low occurrence of leaf fungi and scale as well as damage to leaves and stems, indicate that populations are generally healthy with regard to pests and disease. Percentage live and dead heads, dead canopy and dead trunks for surveyed trees were highly variable across populations. At present, the 12 surveyed South African A. dichotomum populations appear to be in good health and are recruiting. Our study highlights that the choice of population surveyed is of importance and that a wide range of populations in close proximity to one another and at different sites situated far apart have to be surveyed in order to produce an unbiased assessment of populations. [ABSTRACT FROM AUTHOR]

More than half of the patients developed a postpartum hemorrhage, necessitating a hysterectomy for bleeding control in four cases, although the risk for both seemed lower in those patients in whom the hemangioma was diagnosed before delivery. Secondary outcomes included the occurrence of pregnancy complications, preterm delivery rate, perinatal blood loss, perinatal hysterectomy incidence and neonatal ICU-admission. This systematic review is aimed to summarise all published uterine hemangioma cases in pregnant women. [Extracted from the article]

Effective management of conservation areas is critical to ensure the adequate protection of the natural resources. The landscape unit concept can be used as a tool in conservation management as a spatial planning unit. Landscape units are areas with a specific set of biotic and abiotic characteristics that can be classified, mapped and described. These units then form the basis on which a conservation area can be planned and managed. A vegetation map was compiled for Tankwa Karoo National Park (TKNP), when it was originally proclaimed at 27,064 ha. The park has subsequently expanded to more than 145,000 ha and is still growing. A need has been identified by park management as well as scientists working in the park for an effective framework for managing the park, and for conducting scientific research. The latest vegetation map of South Africa is at too coarse a scale for park planning. The purpose of the current study was to classify, map and describe the current extent of the TKNP to fulfill this need. Two primary zones were identified for the park: the Tanqua Plains Zone and the Roggeveld Mountain Zone. These two zones were further subdivided into landscape units using land type units and a combination of field work and satellite imagery. Futhermore, the landscape units were related to habitats and/or vegetation types as identified during previous studies in the area. Environmental parameters for each landscape unit were summarised in order to provide additional information for consideration in management and research decisions. Thirteen landscape units were identified in the current TKNP and are mapped and described. Delineation of the TKNP into landscape units will aid in the effective conservation management of this large national park as well as facilitate scientifc research and monitoring. [ABSTRACT FROM AUTHOR]

A growing scholarship links quality-assured multiple-choice testing to accountable outputs. This article looks at the use of multiple-choice assessment and the quality assuring of item development through a structured process of systematic steps. A qualitative investigation was undertaken based on individual e-interviews with participants who are experts in the use of multiplechoice question assessment. The investigation was conducted at the College of Education of a higher education institution. The findings confirm the potential of multiple-choice assessment to test factual knowledge and higher-order learning. The findings also show that the main components in a systematic process of quality assuring the construction of multiple-choice items include training in the skills of item development, peer reviewing of constructed items, professional editing, and the interpretation of statistical analysis of student performance and student feedback for future constructions. The findings contribute to the literature that argues for credible assessment practices to ascertain relevant outputs. [ABSTRACT FROM AUTHOR]

The article discusses the prosecution related to genocide in South Africa. Topics discussed include Inflammatory speech, insidious propaganda and incitement to crime precede genocide, acts precursory to or preparatory of genocide are not directly criminalised under international law, and hate speech. Other topics discussed include International Criminal Tribunal for Rwanda (ICTR) as a legal institution providing conviction for committing genocide.

The article presents a study which compares the accuracy of clinical and magnetic resonance imaging (MRI) staging of cervical cancer. The study gathered data on 128 cervical cancer patients who underwent MRI and 45 patients who proceeded to surgery in which the pathological stage was used as reference standard. Result shows that the comparison between clinical staging and pathological stage indicates concurrences in 43% of the patients.

Colour and phenolic content of red grapes are two of the most important constituents required to produce a quality red wine. In the Robertson grape growing area, difficulty is sometimes experienced with colour development of grapes. This is especially linked to location and most probably greatly influenced by season. Forty four vineyard blocks of the cultivars Pinotage, Merlot, Cabernet Sauvignon and Shiraz, were studied over 3 seasons primarily to focus on colour and phenolic content, but secondly on total soluble solids, titratable acidity and pH of the grapes. High performance liquid chromatography and spectrophotometric methods were used to determine various colour and phenolic parameters present at harvest. This data was used to indicate how colour and phenolic constitution of a part of the Robertson grape growing area was distributed in relation to various factors, such as cultivar and season. GPS points were used to map data for the blocks visually. Results showed variable colour and phenolic content for these grapes based on blocks and phenolic compounds investigated. Shiraz displayed a wider distribution of certain phenolic compounds over the three seasons than the other 3 cultivars. Seasonality had a great influence on these results, with outlying blocks being identified. [ABSTRACT FROM AUTHOR]

The Roggeveld consists of an island of Mountain Renosterveld (Fynbos biome) surrounded by Succulent Karoo biome vegetation. Since management of abandoned croplands depends on a better understanding of their succession sequences, vegetation recovery on abandoned croplands in the Roggeveld was studied using species and life form diversity parameters. Abandoned croplands of different ages were compared with each other and to the natural vegetation. Therophytes and chamaephytes were the most abundant life forms. Chamaephytes made an overwhelming contribution to the relative cover. Species-area curves (exponential function) differed significantly between the abandoned croplands and natural vegetation. Species richness increased with time since abandonment but no similar increase in species evenness, Shannon or Simpson indices were found. A regression of species richness against age of abandoned cropland predicted that an abandoned cropland of approximately 33 years should be as species rich as the natural vegetation, but a principal cooordinate analysis of floristic data indicated that all the plots were floristically still extremely different from the natural vegetation. Across all nine survey plots only 15 species contributed to a high cover on the plots. Vegetation recovery on abandoned croplands in the Roggeveld occurs naturally, yet the rate of recovery varies among the life forms. [ABSTRACT FROM PUBLISHER]

Abstract: The Hantam-Tanqua-Roggeveld subregion is situated in an area where the Fynbos, Succulent Karoo and Nama Karoo biomes meet. Life form spectra were compiled at a species richness and vegetation cover level in order to determine the affinities of the vegetation of the subregion with respect to its Succulent Karoo, Fynbos and Nama Karoo Biome status. A percentage succulence was also calculated for both species richness and cover. Comparisons of life form spectra and succulence were made across the eight vegetation associations found in the area and across three broad vegetation groups, i.e., Mountain Renosterveld, Winter Rainfall Karoo and Tanqua Karoo. Mountain Renosterveld vegetation was characterised by high chamaephyte, cryptophyte and therophyte species contributions. Compared to the other broad vegetation groups, the Mountain Renosterveld group showed phanerophyte contributions at the vegetation cover level to be highest, but the degree of succulence was low. Winter Rainfall Karoo vegetation was co-dominated by high levels of chamaephyte, cryptophyte and therophyte species with chamaephytes dominating the vegetation cover. Succulent contributions to species richness and cover values were higher than for Mountain Renosterveld vegetation. Tanqua Karoo vegetation was dominated by chamaephyte species or co-dominated by chamaephyte and cryptophyte species with therophyte species contributions lowest of all vegetation groups. Contributions by succulent species to richness and vegetation cover were high in the Tanqua Karoo. Life form spectra of the Mountain Renosterveld associations compared poorly to other sites in the Fynbos Biome. However, the low level of succulence in the Mountain Renosterveld associations also precludes its inclusion into the Succulent Karoo Biome. The large contribution of succulent species at a species and vegetation cover level in Winter Rainfall Karoo and Tanqua Karoo associations confirms that these two groups belong to the Succulent Karoo Biome. Affinities to the Nama Karoo Biome were indicated by the low level of succulence at a vegetation cover level in one of the Winter Rainfall Karoo associations (Roggeveld Karoo). [Copyright &y& Elsevier]

To sustain research outputs while progressively ensuring that staff profiles reflect demographic realities, the College of Human Sciences at the institution under study embarked on a formal mentoring programme in April 2009. The focus of the programme is to mentor newcomers to academe by productive academics who will be retiring from the system over the following decade. The aim of the research was to investigate the functioning of the formal mentoring programme and to determine the extent to which the programme provided for research output opportunities after one year of implementation. A qualitative intrinsic case study approach was followed, employing document study and in-depth individual interviewing. It was found that planning had been thoroughly done and the formal mentoring programme was professionally implemented. Concerns about an initially too formalised approach were counteracted by building flexibility into the reporting on mentoring initiatives. A cost to mentoring was found to arise from the fast-tracking of unrealistic research output expectations. [ABSTRACT FROM AUTHOR]

Abstract: The Mountain Renosterveld vegetation of the Roggeveld is an escarpment type renosterveld showing strong karroid affinities. Fire plays an important role as a landscape scale disturbance that shapes plant communities in this vegetation type, however, post-fire succession has never before been documented for renosterveld vegetation. A study was therefore conducted in the northern Roggeveld to improve our understanding of the recovery of the vegetation following fire. The natural vegetation recovery was analysed using line transect data accumulated at five different sites over a ten year period. This paper reports on the post-fire vegetation trends with respect to changes in species composition, species richness, life form composition and life form richness. Vegetation cover began to re-establish within the first nine months following the fire, and remained at a high level from years 3 to 10. At the first survey the species richness varied from 13 to 17 species, with the highest species richness (14 to 31 species) generally encountered at each transect after three years. The highest Shannon index values were generally found within the first three years and the lowest Shannon index values were found in years 9 and 10. In all cases the Principal Co-ordinate Analysis ordinations of the species composition data indicated a clear separation in the species composition between the first two years (years 1 and 2) following the fire and the remaining years (year 3 to 10). This study also supports the ‘initial floristic composition’ model of Egler (1954) in that all or the majority of species encountered during the succession were already present at the beginning of the recovery phase and there was a rapid re-establishment of the initial plant community. [ABSTRACT FROM AUTHOR]

Presents information on a study which investigated the duodenal and whole empty body essential amino acid profile of South African Mutton Merino lambs which were fed a standard growth diet. Materials and methods; Results and discussion; Conclusions.

Presents information on a study which investigated the essential amino acid composition of the whole empty body of South African Mutton Merino ram lambs. Materials and methods; Results and discussion; Conclusions.

Presents information on a study which investigated the essential amino acid composition of the carcass and duodenal digesta content of South African Mutton Merino ram lambs. Materials and methods; Results and discussion; Conclusions.

Bayesian theory is applied to compare the characteristics of the estimated lactation curves of two groups of 5-year-old Merino ewes. The diets of the two groups were supplemented respectively by DL-methionine and maleyl-DLmethionine. The purpose is to illustrate the Bayesian approach when analysing for the effect of supplement on the lactation pattern of the sheep. Using Wood's model, the posterior distributions of the model parameters are determined for the two groups. This is achieved by assuming a hierarchical Bayes model and applying the Gibbs sampler, a sampling based computer intensive algorithm that is very efficient in obtaining marginal distributions of functions of parameters. The Gibbs sampler enables us to obtain marginal posterior distribution of characteristics of the lactation curve such as peak yield, time of peak yield, persistency and total milk yield. The results are notable differences in the marginal posterior distributions of mean peak milk yield and mean total yield. The posterior probability that the mean peak milk yield of the group supplemented by maleyl-DL-methionine is higher than that of the group with DL-methionine supplement is 0·98, while the same probability for mean total yield is 0·83. [ABSTRACT FROM PUBLISHER]

The effects of fertilization (100 kg nitrogen plus 10kg phosphorus per ha per year) of Cymbopogon-Themeda veld on certain chemical components in vitro dry-matter digestibility (IVDMD), intake by either lactating cows or steers as well as daily gain of pre-weaned calves or steers, were determined in the summer rainfall area of the Republic of South Africa.The nutritive value of fertilized veld herbage was, in terms of crude protein and acid-detergent fibre content, IVDMD and herbage intake, superior to that of unfertilized veld. Species, classified as palatable according to the literature, were more abundant on the fertilized veld than on the unfertilized veld. In spite of the fact that the stocking rate on the fertilized veld was double that of the unfertilized veld, the average daily gain (ADG) of steers on the former was higher than that of steers on the latter. There was no significant difference in the ADG of the pre-weaned calves, whose dams grazed either fertilized or unfertilized veld. It was calculated that the fertilization of veld for growing steers can (under the conditions that prevailed) be a financially viable proposition if the beef price per kg live weight amounts to at least 0·65% of the cost of fertilization per ha. [ABSTRACT FROM PUBLISHER]

The milk production of 63 5-year-old Merino ewes was measured over a 16-week period after lambing. The purpose was to find a suitable mathematical model to represent the lactation curve of Merino sheep and to estimate the parameters of the model for an individual ewe from a single data point in early lactation. Three models were considered, the three-parameter Wood model, yn = nb exp(a + en), the four-parameter Morant model, yn = exp(a + bn + en2 + d/n and the six-parameter Grossman model, yn = a1b1 - [tanh2 (b1n - c1))] + a2b2[1 – tanh2 (b2(n -c2,))].The Grossman model was found to be inappropriate for the available data, while there seems to be little difference in the suitability of the other two models. The Wood and Morant models both seem adequate to represent the lactation curve. A pattern in the estimated residuals suggests possible autocorrelations in the errors, but this is inconclusive due to the limited number of data points per animal.The correlation between the estimated parameters of the model and the daily yield measured during the 1st week of lactation enabled us to use linear regression to estimate the lactation curve of an individual animal based on the 1st week's yield. Confidence and prediction intervals for the yield during the rest of the lactation period may then also be constructed. This makes it possible to extend incomplete milk records for use in genetic evaluation, formulation of rations and economic evaluations. [ABSTRACT FROM PUBLISHER]

Phosphoric acid at different concentrations has been extensively used as an etching agent to improve bonding of dental materials to enamel surfaces. Recently attention has been drawn to the possible use of polyfunctional organic acids as conditioning agents. The object of this investigation was to determine the optimal concentration of pyruvic acid as an etching agent. A commercial composite resin with an intermediary bonding system supplied with 37% H3PO4 as an etching agent was used as the control system. In addition, a comparative study was carried out to evaluate 37% H3PO4, 20% lactic acid and the optimal concentration of pyruvic acid as conditioning solutions. Etching enamel surfaces with 10% pyruvic acid resulted in the optimal tensile bond strength of the resin to etched enamel surfaces. The use of 10% pyruvic acid did not adversely affect the bond strength of the resin system when compared to enamel surfaces etched with 37% H3PO4 for the same time period. Significantly lower tensile bond strengths were recorded on enamel surfaces etched with 20% lactic acid. The rate and depth of etching obtained with 37% H3PO4 can be considerably reduced by using 10% pyruvic acid as the conditioning agent. [ABSTRACT FROM AUTHOR]

An abstract of the research paper "Added value of website based parent information about intrauterine treatment for severe congenital diaphragmatic hernia," by A. Engels and colleagues is presented.

The effect on production performance of a synthetic or natural antioxidant and lipid saturation in the finishing diets of lambs was investigated. The four dietary treatments consisted of the same basal diet (187 g CP, 355 g NDF, and 71 g EE per kg DM), differing only in regard to the supplemental lipid source (30 g/kg of either saturated beef tallow or unsaturated soybean oil) and type of antioxidant (125 g/ton of either a synthetic or natural antioxidant) included, in a 2 x 2 factorial design experiment. Eighty-four S.A. Mutton Merino lambs (27.64 + 1.72 kg) were randomly allocated to the four dietary treatments (n = 21 lambs per treatment) and subdivided into 7 replicates per treatment (n = 3 lambs per replicate). After a dietary adaptation period of 8 days, all lambs received the respective experimental diets for the remaining period (41 days). The average daily DM feed intake, weight gain and feed efficiency was calculated accordingly. No significant differences in DMI, ADG and the efficiency with which ingested feed were utilized (FCR), were recorded for the treatments. However, the addition of unsaturated soybean oil to the diet significantly increased the efficiency with which the ME of the diet was utilized. In contrast with the natural antioxidant, the inclusion of unsaturated soybean oil in the diet containing a synthetic antioxidant, resulted in a significant lower MEI by the lambs -- indicating that a lipid x antioxidant interaction occurred. Results of the present study seem to indicate that dietary lipid saturation in the finishing diets of lambs had no influence on their growth performance. However, a more efficient utilisation of ME in the finishing diet containing unsaturated soybean oil, compared to the saturated beef tallow, did occur. [ABSTRACT FROM AUTHOR]

A study was conducted to investigate the effect of dietary lipid saturation on nutrient digestibility of layer diets. Five isoenergetic (12.6 MJ AME/kg DM) and isonitrogenous (170 g CP/kg DM) diets were formulated using different lipid sources at a constant 30 g/kg inclusion level. The control n-3 diet was formulated using a blend (50 : 50) of linseed- and fish oil, while fish oil (polyunsaturated n-3), sunflower oil (polyunsaturated n-6), high oleic acid (HO) sunflower oil (monounsaturated n-9) and tallow (saturated fatty acid) were used as other supplementary lipid sources. The five dietary treatments were randomly allocated to the two hundred (200) individually caged Hy-Line Silver-Brown laying hens (20 weeks of age) (n = 40/treatment). Experimental diets were provided to the birds on an ad libitum basis for a 22 week period (from 20 to 42 weeks of age). At 42 weeks of age, six hens per treatment (n = 6 replicates/treatment), were randomly selected to partake in a digestibility study over a 7 day period using the total collection technique. The polyunsaturated n-6 treatment resulted in the lowest crude protein digestibility, whereas the saturated fatty acid treatment resulted in the lowest fat digestibility. Furthermore, the polyunsaturated n-3 diet resulted in the highest dietary AME (13.29 MJ/kg DM) and AMEn (12.74 MJ/kg DM) content. [ABSTRACT FROM AUTHOR]

The influence of a synthetic or natural antioxidant and lipid saturation on the apparent digestibility of nutrients in a standard lamb finishing diet was investigated. The four dietary treatments consisted of the same basal diet, providing 187 g CP-, 355 g NDF- and 71 g EE per kg DM, but differing in supplemental lipid source (30 g/kg of either saturated beef tallow or unsaturated soybean oil) and type of antioxidant included (125 g/ton of either a synthetic or natural antioxidant). The digestibility study was conducted over a period of 12 days (including a 4-day adaptation to the faecal collection bags). Twenty-eight S.A. Mutton Merino lambs (45.1 ± 3.0 kg) were randomly allocated to the four dietary treatments (n = 7 lambs/treatment). Composite feed, feed refusal and faecal samples of individually penned lambs were collected for chemical analysis. The apparent digestibility coefficients, digestible nutrient and available energy content were calculated accordingly. The DMI of the lambs did not differ significantly between the various experimental diets. The inclusion of unsaturated soybean oil reduced the apparent digestibility of NDF in the diet. The apparent digestibility of NDF seems to be higher when a natural antioxidant was included in the diet. The comparatively negative effects of the unsaturated lipid source and synthetic antioxidant on the apparent digestibility of NDF were associated with a significantly lower digestible NDF content in the experimental diet. Accordingly, soybean oil resulted in a significantly lower ME content in the diet. However, estimating ME from DE with a constant factor of 0.8 probably underestimates the ME content of diets supplemented with lipids rich in unsaturated fatty acids. The latter are known to reduce methane production, and hence, energy losses. [ABSTRACT FROM AUTHOR]

A study was conducted to evaluate the effects of a rumen-specific, active live yeast (Saccharomyces cerevisiae; SC CNCM I-1077), alone or in combination with an ionophore (lasalocid-Na) in standard feedlot diets, on production performance and carcass quality of lambs. Sixty South African (S.A.) Mutton Merino lambs, weighing 25.7 ± 2.2 kg, were randomly allocated to four treatments (15 lambs per treatment) and further subdivided into five replicates per treatment (three lambs per replicate). The four dietary treatments consisted of an iso-nitrogenous and iso-energetic basal diet (177 g crude protein (CP)/kg dry matter (DM) and 276 g neutral detergent fibre (NDF)/kg DM) differing only in the additive included, i.e. (i) the control (C) diet (no additive), (ii) live yeast (SC) (220 g/ton), (iii) ionophore (G) (120 g/ton) and (iv) both live yeast with ionophore (SCG) at the same mentioned levels. After adaptation (8 days), the experimental diets were fed for 47 days in a finishing period. Feed intake and body weights were recorded weekly. At completion all animals were slaughtered (44.5 ± 3.8 kg) and the cold (2 °C) carcass weight and carcass characteristics recorded. Dietary treatment had no effect on feed intake, daily live weight gain, feed conversion ratio, carcass weight and carcass characteristics. Carcasses were leaner on the ionophore treatment (G) in comparison to the control diet (C). The results suggested that this rumen-specific live yeast included alone or in combination with an ionophore in finishing diets, containing less than 28% NDF/kg DM, did not affect performance and carcass traits of S.A. Mutton Merino lambs. [ABSTRACT FROM AUTHOR]

A study was conducted to evaluate the effects of dietary replacement of maize with popcorn waste (PW) on the intake, nutrient digestibility and growth performance of lambs. Diets replacing 0, 25, 50, 75 and 100% maize with PW were formulated and fed ad libitum to 40 South African Mutton Merino lambs (25.0 ± 0.45 kg live-weight). The diets had similar intake and nutrient digestibility of dry matter (DM), organic matter (OM) and neutral detergent fibre (NDF). Lambs fed the 25 and 50% PW diets had higher intakes of crude protein (CP), metabolizable energy and ether extract compared to the other diets. Growth rate was highest (226 g/d) on the 25% diet and lowest (109 g/d) on the 75% PW diet. Best feed conversion ratio (FCR), of 5.1 (kg feed/kg live weight) was obtained with the 0% PW diet. Improved digestibility of CP and EE occurred in the 25 and 75% PW diets. Higher intake of nitrogen (N) and N retention were obtained in the 25 and 50% PW diets. Dietary replacement of >75% of maize resulted in poor animal performance (ADG < 150 g/d and FCR >7.00). It was concluded that PW can replace up to 50% of the maize in diets for growing lambs. [ABSTRACT FROM AUTHOR]

A study was conducted to determine the influence of different particle size limestone in layer diets on egg production and eggshell quality during the later stages of egg production (>54 weeks of age). Calcitic limestone (360 g Ca/kg), consisting of small (<1.0 mm), medium (1.0 - 2.0 mm) and large (2.0 - 3.8 mm) particles were obtained from a specific South African source that is extensively used in poultry diets Isoenergetic (14.32 MJ AME/kg DM) and isonitrogenous (172.01 g CP/kg DM) diets with a dietary Ca content of 39.95 g Ca/kg DM were used. Sixty nine, individual caged Lohmann-Silver pullets, 17 weeks of age, were randomly allocated to the three treatments (n = 23) for the determination of various egg production and eggshell quality characteristics. Egg production and eggshell quality data recorded on individual basis at 54, 58, 64 and 70 weeks of age were pooled to calculate and statistical analysed parameter means for the late production period. Different limestone particle sizes had no effect on any of the tested egg production and eggshell quality parameters. These results suggested that larger particles limestone are not necessarily essential to provide sufficient Ca2+ to laying hens for egg production and eggshell quality at end-of-lay, provided that the dietary Ca content satisfies the requirements of the laying hen. [ABSTRACT FROM AUTHOR]

The obtaining of a representative sample is crucial for the application of an accurate and uniform lucerne hay grading system in South Africa. There is currently limited data available on the effect of the inside diameter of the coring probe on the chemical composition of the lucerne hay samples. A study was therefore undertaken to determine the influence of the inside diameter of a coring probe on the chemical composition of unground lucerne hay samples using the Near Infrared Reflectance Spectroscopy (NIRS) technique. Ten lucerne bales (total 40), randomly chosen from four different grades (Prime, Grade 1, 2 and 3 according to the National Lucerne Trust quality and grading system), were sampled with both a large probe (35 mm inside diameter and 520 mm long) and a small probe (12 mm inside diameter and 450 mm long). The samples with each probe were taken at approximately the same location in the bale. The samples were analysed with the NIRS for crude protein (CP), acid detergent fibre (ADF), neutral detergent fibre (NDF), ash and lignin. The model to calculate the new lucerne quality index (NLQI) from the ADF, ash and lignin, according to the National Lucerne Trust quality and grading scheme was used. Regression analysis revealed a significant relationship (r²) between the results of the large and small probe namely CP = 0.77, ADF = 0.95, NDF = 0.94, ash = 0.92, lignin = 0.87 and NLQI = 0.97. Sampling of lucerne hay with a large and small probe was irrelevant as resulted in similar chemical composition results. [ABSTRACT FROM AUTHOR]

A study with the aim of evaluating the reversibility of the nutritionally induced changes in the scrotal and testicular characteristics of young rams was conducted. Thirty-six Dorper rams, 11 to 12 months of age were randomly divided into three groups of 12 rams each and fed at different energy levels for 127 days. At the end of this period, half of the animals from each group (n = 6) were slaughtered. In the second phase of the trial, the energy level of the diet was standardised and all animals were fed on the same low energy diet for 90 days, before being slaughtered. The carcass, scrotal and testicular characteristics of the slaughtered animals were assessed at the end of each phase and the results compared within groups to evaluate the reversibility of the nutritionally induced changes. Results indicate that scrotal fat deposited during periods of high-energy intake was mobilised during periods of restricted energy availability. [ABSTRACT FROM AUTHOR]

A study with the aim to evaluate the effects of different dietary energy concentration (8.23, 9.77 and 11.32 MJ ME/kg DM) on scrotal, testicular and semen characteristics of young Dorper rams was conducted during the breeding season. Thirty-six 11-12 month old Dorper rams were randomly allocated to three groups of 12 rams each and fed at different energy concentrations for 127 days. Semen was collected fortnightly from every ram to evaluate semen characteristics. At the end of the trial period, six rams from each group were slaughtered and the carcass, scrotal and testicular characteristics evaluated. Results indicate that although higher energy concentrations accelerate testicular development and resulted in scrotal fat deposition, these induced changes had no significant effect on semen quality and quantity. [ABSTRACT FROM AUTHOR]