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Multivariate analysis was carried out for 16 groundnut genotypes evaluated for 12 agromorphological characters. The crop was sown during2015/16 Ethiopian wet season in four locations in RCBD to study the variability and their... more
Multivariate analysis was carried out for 16 groundnut genotypes evaluated for 12 agromorphological characters. The crop was sown during2015/16 Ethiopian wet season in four locations in RCBD to study the variability and their interrelationship and divergence pattern based on quantitative traits. The distance matrix was used to study genetic diversity among the genotypes based on principal component analysis, discriminant analysis and clustering methods. Genetic divergence of groundnut genotypes through distance matrix based on Euclidean distance (D) revealed that there was small range of genetic diversity. The Eigen vectors for the first three component loading has shown that the first principal component had high positive component loading from NBP, AGBP, NMP, PWP, SWP as well as GY characters and found to associate with NC 343, Baha jidu, Lote, Manipeter, Roba, Werer 962, Tole1, Tole2 and Oldhale genotypes with high positive PCA1 scores based on Euclidean distance matrix(D). In co...
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The Department of Health (DoH) has identified processed meats and raw processed meat sausages as the meat product primarily responsible for salt intake among the South African population, and is giving manufacturers five years to... more
The Department of Health (DoH) has identified processed meats and raw processed meat sausages as the meat product primarily responsible for salt intake among the South African population, and is giving manufacturers five years to gradually reduce sodium levels in order to condition consumers to lower salt content.
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The effect of 4kGy ionisation irradiation, combined with ripening temperatures at 8°C and 16°C on the ripening of Cheddar cheese was investigated. Changes in cheeses were monitored by sensory, microbiological, and chemical analyses.... more
The effect of 4kGy ionisation irradiation, combined with ripening temperatures at 8°C and 16°C on the ripening of Cheddar cheese was investigated. Changes in cheeses were monitored by sensory, microbiological, and chemical analyses. Sensorically, no cheese was preferred above the other. At 16°C ripening, irradiation affected the bacterial groups, but not the psychrotrophs. The free fatty acid content of the cheeses was not affected by irradiation, but higher thiobarbituric acid-values were observed after ripening at 16°C, as well as higher water-soluble nitrogen/total nitrogen. Differences in proteolysis products were detected by urea-page and RP-HPLC.
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Sodium (Na) reduction and replacement were evaluated in traditional South African sausages (boerewors). The Na levels were adjusted to contain the Na inclusion limits of South African regulations for 2017 and 2019, on its own and in... more
Sodium (Na) reduction and replacement were evaluated in traditional South African sausages (boerewors). The Na levels were adjusted to contain the Na inclusion limits of South African regulations for 2017 and 2019, on its own and in combination with different replacers (KCl and K-lactate). The effect of these treatments was evaluated in terms of chemical (ash, NaCl, Na, and chloride contents, pH, water activity ( a w ), lipid oxidative stability (TBARS), colour, and thaw and cooking losses), microbial (total viable count (TVC), coliform count, and yeast and mould count), and sensory (appearance, flavour, saltiness, and texture overall liking) characteristics. Lipid oxidative stability was comparable for all the treatments no longer than 6 days at 4°C. When the boerewors treatments were frozen for 180 days, the potassium-containing models with lowered levels of NaCl, indicated better secondary lipid oxidative stability than the models containing only Na. The red colour of the boerewo...
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We present the first report on the effect of graded levels of Moringa oleifera leaf meal (MOLM) (0, 0.25, and 0.5%) and fat (0, 10, and 15%) on fatty acid profile, lipid oxidation, and proximate composition of chicken droëwors. On... more
We present the first report on the effect of graded levels of Moringa oleifera leaf meal (MOLM) (0, 0.25, and 0.5%) and fat (0, 10, and 15%) on fatty acid profile, lipid oxidation, and proximate composition of chicken droëwors. On triplicate samples of all treatments, proximate analysis was done, the total lipid was quantitatively extracted using chloroform and methanol in a ratio of 2 : 1, fatty acid profiles were determined, and thiobarbituric acid reactive substances (TBARS) were measured. The present study showed that droëwors manufactured with 0% fat inclusion had less fat and more protein than those made with 10% and 15% fat. All treatments contained a greater percentage of C18:1c9 (oleic) (30.95 to 32.65%) acid than other fatty acids and a higher proportion of unsaturated fatty acids than saturated. T9 (15% fat, 0.5% MOLM) had significantly ( P < 0.05 ) higher PUFAs than T1 (0% fat, 0% MOLM) and T4 (10% fat, 0% MOLM). Treatments with 0.5% MOLM had significantly lower TBARS...
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Inexpensive fibre sources might be used as an alternative to lucerne hay in diets for finishing lambs. Thus, effects of providing fibre from lucerne hay (LH), soyhulls (SH), maize stover (MS) and Eragrostis teff hay (ET) on the nutrient... more
Inexpensive fibre sources might be used as an alternative to lucerne hay in diets for finishing lambs. Thus, effects of providing fibre from lucerne hay (LH), soyhulls (SH), maize stover (MS) and Eragrostis teff hay (ET) on the nutrient digestibility of diets of finishing lambs with comparable NDF and nutrient concentration were evaluated. Thirty-six individually housed Merino ram lambs (x̄ = 43.03, SD = 3.72 kg) were randomly allocated to four diets (n = 9 lambs/treatment). A digestibility study was conducted to determine the nutrient availability of these diets. Dry matter (DM) intake of SH (1436 g) was lower than ET (1716 g). No differences were recorded between treatments for digestibility of NDF (0.32 - 0.34), acid detergent fibre (ADF) (0.41 - 0.44), and ether extract (EE) (0.67 - 0.75), except that MS (0.23) had lower NDF digestibility. Digestibility of DM, organic matter (OM) and non-structural carbohydrates (NSC) were similar for the LH (0.72; 0.75; 0.96) and SH (0.70; 0.74...
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Sixteen groundnut genotypes (including local check) were evaluated for quantitative parameters. The crop was sown during 2015 wet season in Ethiopia across four locations. The experiment was laid out in Randomized Complete Block Design... more
Sixteen groundnut genotypes (including local check) were evaluated for quantitative parameters. The crop was sown during 2015 wet season in Ethiopia across four locations. The experiment was laid out in Randomized Complete Block Design with three replications. Twelve quantitative parameters were studied. The analysis of variance revealed the prevalence of significant difference among the genotypes for all studied parameters. Based on mean performance of genotypes Beha gudo, Manipeter and Werer-962 were found to be best for grain yield in kg/ha. High to moderate estimates of genotypic coefficient of variation (GCV) and phenotypic coefficient of variation (PCV) were exhibited by all characters except for SHP and NSP indicating that those characters could be used as selection indices for crop improvement. High heritability was observed for 100SW (91.2%), AGBP (90.3%), NBP (90.2%), PH (89.4%), NMP (86.8%), NSPOD (85.7%), HI (83.7%) and KY (79.7%) accompanied by high genetic advance indi...
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Background: Eisenia foetida are used as a feed source. However, information on nutrient composition and fatty acid profiles of earthworm E.foetida is limited, making it complex to include them into feed formulation. Objective: The aim of... more
Background: Eisenia foetida are used as a feed source. However, information on nutrient composition and fatty acid profiles of earthworm E.foetida is limited, making it complex to include them into feed formulation. Objective: The aim of this study was to determine the nutritive value of freeze-dried and oven-dried earthworms, E. foetida. Design: The earthworms were oven- or freeze-dried, then analysed for nutrient composition (protein, fat, moisture and minerals) according to AOAC method and fatty acids using gas chromatography. Results: Protein content was higher in freeze-dried earthworms while fat content of earthworms was not influenced by drying methods used. Most minerals (macro and micro) of E. foetida were significantly different except for calcium (P 0.05) were observed on Margaric, Vaccenic, Arachidic, Tricosanoic, omega-3, SFA, MUFA, n-3, PUFA: SFA and PUFA/MUFA between oven-dried and freeze-dried samples. Conclusions: The study revealed that freeze-dried E. foetida can ...
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The proximate composition of milk from fifteen free-ranging white rhinoceroses at different lactation stages is reported with detailed analysis of fatty acid composition and minerals. Lactose is the main component at 7.93 ± 0.53%,... more
The proximate composition of milk from fifteen free-ranging white rhinoceroses at different lactation stages is reported with detailed analysis of fatty acid composition and minerals. Lactose is the main component at 7.93 ± 0.53%, followed by 0.93 ± 0.19% protein, 1.76 ± 0.39% fat, 0.40 ± 0.18% ash, 0.05 ± 0.01% glucose, and 0.04 ± 0.02% non protein nitrogen The interindividual variation of all the components is high, showing no trend of change over lactation. The K and P content decreased over lactation. The fatty acid composition of rhinoceros milk is characteristic with a high saturated fatty acids content of 62%-84%, of which the medium chain fatty acids form the major portion. The C10:0, C12:0, C16:0, and C18:1c9 are the major fatty acids in the milk fat. The results are compared with the two other Perissodactylae families, the Equidae and Tapiridae. Differences in gross composition are small, but the milk of the Rhinocerotidae have the lowest gross energy, while the milk fats consist of the highest amounts of saturated fatty acids, while the low levels of C16:1c9 and C18:1c9 indicate the lowest mammary Δ9-desaturase activity.
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Research Interests: Biology and Food Sciences
Research Interests: Chemistry, Food Science, Medicine, Animal Production, Fatty Acid, and 3 moreMeal, Broiler, and Canola
SUMMARY The effect of dietary Moringa oleifera leaf meal (MOLM) on the quality and fatty acid profile of meat from 3 chicken strains, normally used in low‐input, extensive production systems, was evaluated. The MOLM was included in a... more
SUMMARY The effect of dietary Moringa oleifera leaf meal (MOLM) on the quality and fatty acid profile of meat from 3 chicken strains, normally used in low‐input, extensive production systems, was evaluated. The MOLM was included in a commercial broiler finisher diet at 0 (MOLM0), 25 (MOLM25), 50 (MOLM50), and 100 (MOLM100) g/kg. All diets were formulated to be isonitrogenous and isoenergetic. Two hundred and sixteen (216) Potchefstroom Koekoek (PK), Ovambo (OV) and Black Australorp (BA) chickens were offered the diets for a period of 13 wk in a 2 × 3 × 4 factorial treatment arrangement in a complete randomized design (CRD). The 3‐way interaction (diet × strain × gender) term did not (P > 0.05) affect redness (a*), yellowness (b*), pH or meat cooking loss, but significantly influenced (P < 0.001) lightness (L*) and shear force. In OV female chickens fed MOLM25, MOLM50, and MOLM100, shear force did not differ significantly; only MOLM0 had significantly higher shear force. However, OV male chickens, feeding MOLM50 resulted in lower shear force. The MOLM0, MOLM50, and MOLM100 had the lowest cooking loss values for BA; however, no dietary differences were observed in OV and PK. The fatty acid profile of meat from chickens offered the control diet was similar to those offered MOLM‐based diets. Chicken strains varied (P < 0.05) in terms of eicosatrienoic acid, docosahexanoic acid and palmitic acid contents. It can be concluded that using M. oleifera leaf as a feed supplement resulted in lower shear force for OV females only but did not alter the fatty acid profile of meat.
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ABSTRACT The recent increase in human population coupled with rural- to-urban migration has led to challenges in managing a balanced diet in both food ‘secure’ and food ‘insecure’ regions. As a result of this geographic phenomenon, the... more
ABSTRACT The recent increase in human population coupled with rural- to-urban migration has led to challenges in managing a balanced diet in both food ‘secure’ and food ‘insecure’ regions. As a result of this geographic phenomenon, the human population continues to suffer from caloric -related conditions and diseases, including obesity and coronary heart diseases. In addition, fat and fatty acid composition of the diet has come under severe attack from the media and different human nutrition corridors in the past as they have been implicated in aiding the increase in cases of coronary heart diseases despite their important roles in cellular functions. In this view, fat and fatty acids is of great significance to the modern society, which aims at balancing their dietary proportions for efficient functionality of the human body systems. To improve food and nutrition, understanding the physiological function of the body and biochemical function of the fatty acids and polar lipids and getting a clearer view of the socio-economic aspects surrounding food consumption is also important. However, to further enhance the utilisation of fats accessed from diets, it is important to highlight significant current innovative technologies used to improve food fatty acid profiles and the influence of media on dietary and food consumption patterns. This review discusses the significance of health -related fatty acids, socio-economic aspects governing their presence in food and consumption, and how all these factors have a bearing on achieving the goal of human health, well - being and food and nutrition security.
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Boerewors is a South African fresh sausage preserved with 450mg/kg sulphur dioxide (SO(2)). The preservative effects of rosemary (Ros; 260mg/kg) and chitosan (Chi; 10g/kg) were compared to SO(2). Eight boerewors models were formulated.... more
Boerewors is a South African fresh sausage preserved with 450mg/kg sulphur dioxide (SO(2)). The preservative effects of rosemary (Ros; 260mg/kg) and chitosan (Chi; 10g/kg) were compared to SO(2). Eight boerewors models were formulated. Microbial, colour, lipid and sensory characteristics were evaluated. Chi and Chi in combination with other preservatives had a significant effect on reducing total bacterial, coliform and Enterobacteriaceae counts, comparable to SO(2). Chi, however, had a better effect on decreasing yeasts and mould counts than SO(2). Chi showed good colour properties comparable to SO(2). Ros showed comparable lipid stability to SO(2) but better when compared to Chi. Ros had a better effect on the sensory taste when compared to Chi, but SO(2) was still preferred. Reduced levels of 100mg/kg SO(2) showed good antimicrobial and colour effects in combination with Chi and in combination with Ros as antioxidant and improving the sensory properties. Alternative preservatives can be used to reduce the SO(2) content of boerewors.
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Effects of diets supplemented with or without Moringa oleifera leaf meal (MOLM) on fatty acid (FA) composition and oxidative stability of broiler breast meat during refrigerated storage was determined. Dietary treatments (T) were as... more
Effects of diets supplemented with or without Moringa oleifera leaf meal (MOLM) on fatty acid (FA) composition and oxidative stability of broiler breast meat during refrigerated storage was determined. Dietary treatments (T) were as follows: T1, positive control, 668g/ton Salinomycin and 500g/ton Albac; T2, T3 and T4 contained graded levels of MOLM at 1%, 3% and 5% of dry matter (DM) intake, respectively; and T5, a negative control (0% additives). Oxidative stability was evaluated by thiobarbituric acid reactive substances (TBARS) on day (D) 1-8 of storage at 4°C; and FA analysis was done on samples obtained on D1 and D8. Significant effects on TBARS were noted on day (D) 1, 3, 4 and 7; increased with increasing storage time, and with increase in MOLM supplementation. Highest (P&lt;0.05) C18:0 and C15:0 levels were noted on D1 in T2; C20:0 in T4 on D8; C20:2, C20:3n6 and C22:6n3 in T2; C18:3n6 and P/S ratio in T4 on D1; and n-3 in T3. Thus, despite the high SFA content, additive supplementation of M. oleifera leaf meal up to 5% of the bird&#39;s DMI improved the FA profile and reduced lipid oxidation in broiler breast meat.
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Cold-pressed seed oil from twelve commercially produced cactus pear cultivars was assessed for oil yield, fatty acid composition, physicochemical properties, quality and stability. Large differences in oil content, fatty acid composition... more
Cold-pressed seed oil from twelve commercially produced cactus pear cultivars was assessed for oil yield, fatty acid composition, physicochemical properties, quality and stability. Large differences in oil content, fatty acid composition and physicochemical properties (IV, PV, RI, tocopherols, ORAC, % FFA, OSI and induction time) were observed. Oil content ranged between 2.51% and 5.96% (Meyers and American Giant). The important fatty acids detected were C16:0, C18:0, C18:1c9 and C18:2c9,12, with C18:2c9,12, the dominating fatty acid, ranging from 58.56-65.73%, followed by C18:1c9, ranging between 13.18-16.07%, C16:0, which ranged between 10.97 - 15.07% and C18:0, which ranged between 2.62-3.18%. Other fatty acids such as C14:0, C16:1c9, C17:0, C17:1c10, C20:0, C18:3c9,12,15 and C20:3c8,11,14 were detected in small amounts. The quality parameters of the oils were strongly influenced by oil content, fatty acid composition and physicochemical properties. Oil content, PV, % FFA, RI, IV...
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The existence of genetic variation is essential in plant breeding for increasing yield, wider adaptation, selection of parents for hybridization, desirable quality, and pest or disease resistance. This study was planned to investigate... more
The existence of genetic variation is essential in plant breeding for increasing yield, wider adaptation, selection of parents for hybridization, desirable quality, and pest or disease resistance. This study was planned to investigate genetic variability based on cluster analysis of groundnut cultivars based on morpho-agronomic traits. The crop was sown in randomized complete block design (RCBD) during the 2015 wet season across four locations in Ethiopia. The cluster analysis based on average linkage (UPGMA) of 16 groundnut genotypes, measured for 17 oil traits showed that the most distinct genotypes were Werer-963 and Behagudo (D=10.48), between Werer-963 and Tole-1 (D=10.32), and between Tole-1 and Sedi (D=9.86). The cluster mean analysis based on oil traits and quality parameters has grouped genotypes into 3 clusters. The first cluster constituted 9 genotypes that showed non-significant above average performance for oleic acid, eicosenoic acid, lignoceric acid, total monounsatu...
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Natural food items and the additional benefits they provide have received considerable attention in recent years. Betalains are nutritious pigments which have valuable biological properties, e.g., antioxidant and free radical scavenging... more
Natural food items and the additional benefits they provide have received considerable attention in recent years. Betalains are nutritious pigments which have valuable biological properties, e.g., antioxidant and free radical scavenging activity. In this study, aqueous betalain extracts were obtained from different coloured cactus pears (purple, red/pink, and orange), amaranth, and beetroot, with and without the addition of ascorbic acid, microwave-heated, and freeze-dried and subsequently analysed by thin layer chromatography (TLC). Beetroot samples without the addition of ascorbic acid (AA) had lower phenols, flavonoids, and ascorbic acid content than beetroot samples extracted with the addition of AA. Amaranth had significantly higher contents of antioxidants than all the other plants. Results for phenolic compounds showed that there were no significant differences between cactus pear cultivars, however, significant differences were seen between the two beetroot samples (microwav...
Chryseobacterium species are isolated and taxonomically evaluated from a wide range of sources. While C. gleum and C. indologenes have been implicated in human disease, the potential pathogenicity of numerous other species have not been... more
Chryseobacterium species are isolated and taxonomically evaluated from a wide range of sources. While C. gleum and C. indologenes have been implicated in human disease, the potential pathogenicity of numerous other species have not been investigated. The aims were therefore to evaluate 37 Chryseobacterium species and Elizabethkingia meningoseptica from environmental, food, fish, water and clinical sources for production of haemolysis, growth at 37 °C, and production of virulence enzymes. The control of these strains were investigated by determination of antimicrobial and disinfectant resistance. All the species produced α- or β-haemolysis. In terms of growth at 37 °C and production of virulence enzymes, C. soldanellicola (environmental), C. oranimense (food) and C. koreense (natural mineral water) could be potential human pathogens. Chryseobacterium piscium might be pathogenic to fish. Trimethoprim could be the most effective antimicrobial for the treatment of a Chryseobacterium spe...
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One of the important steps for realizing artificial intelligence is identifying elementary units that are beneficial for neural network construction. A type of memristive behavior in which phase-change nanoclusters nucleate adaptively in... more
One of the important steps for realizing artificial intelligence is identifying elementary units that are beneficial for neural network construction. A type of memristive behavior in which phase-change nanoclusters nucleate adaptively in two adjacent dielectric layers with distinct distribution patterns is demonstrated. This memristive system responds in potentiation to increased stimulation strength and fire action potential after threshold stimulation. Reversible nucleation of phase-change nanoclusters is confirmed after both in situ and ex situ examinations using high-resolution transmission electron microscopy. The dynamics at the nanoscale level dominates the actions of the two dielectric layers. The oscillation response over a long period is due to the competition between crystalline and amorphous phases in the layer near the bottom electrode. Weight mutation, that is, action potential firing, is caused by the blockage of the filament in the layer near the top electrode. The memristive system is compact and able to execute complicated functions of a complete neuron and performs an important role in neuromorphic computing.
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The study was conducted to determine the response in growth performance, physicochemical properties and fatty acid composition of broiler meat fed incremental levels of M. pruriens seed meal. A total of 112 Cobb 500, seven days old,... more
The study was conducted to determine the response in growth performance, physicochemical properties and fatty acid composition of broiler meat fed incremental levels of M. pruriens seed meal. A total of 112 Cobb 500, seven days old, unsexed broiler chicks with body weight of 150 ± 5.47 g/bird (mean ±SD) were used. Chicks were allotted to pens in a completely randomized design hence assigned to four experimental diets containing 0, 10, 15, and 20% of MPSM, respectively. Each diet was offered ad libitum with clean water to 28 broilers in each treatment. There was a linear decrease in average daily feed intake (ADFI), average daily gain (ADG) and final body weight (FBW) with incremental levels of MPSM (P < 0.05). Feed conversion ratio (FCR) increased linearly with increasing MPSM levels while Final Body Wight (FBW) decreased linearly with increasing levels of MPSM (P < 0.05). Meat pH24 and colour parameters showed no relationship with increasing levels of MPSM (P > 0.05). Thaw...
The effect of dietary graded inclusion levels of Imbrasia belina worm meal on meat chemical composition and fatty acid profile of broiler chicken meat was evaluated. A total of 360 chicks were randomly allocated to four dietary... more
The effect of dietary graded inclusion levels of Imbrasia belina worm meal on meat chemical composition and fatty acid profile of broiler chicken meat was evaluated. A total of 360 chicks were randomly allocated to four dietary treatments, with each treatment group replicated 6 times (n = 15/replicate). The inclusion levels of the I. belina worm meal in the treatments were 0% control = T1, T2 = 4%, T3 = 8% and 12%. A three-phase feeding program of starter (0-14d), grower (15-28d), and finisher (29-35d) was employed for the study. The results showed that crude protein content of breast meat was higher (P
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Genetic progress has brought about increase in yield potential per se for almost all production areas around the world. The present study examines the relationship of groundnut yield with year of release, yield components and other... more
Genetic progress has brought about increase in yield potential per se for almost all production areas around the world. The present study examines the relationship of groundnut yield with year of release, yield components and other agro-morphological traits using aggregative data from 1976 to 2012 to calculate genetic gain in groundnut grain yield across four locations in Eastern Ethiopia. The direct method, that compares cultivars with their year of release, was used. The relative gain for groundnut grain yield was 1.08% since 1976. A deeper understanding of these issues facilitates the identification of specific yield-limiting factors that can be used for future breeding strategies. Grain yield, 100 seed weight, plant height and harvest index were significantly correlated with year of release for tested locations, emphasizing the most promising traits for groundnut breeders in the past. These traits were also responsible for the significant genetic progress in groundnut yield in E...
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The objective of the study is to establish the effect of parity on milk composition and fatty acid profiles of Nguni cattle milk. Forty-four Nguni cows with parities ranging from 1 to 13 were included in this study. The cows were grouped... more
The objective of the study is to establish the effect of parity on milk composition and fatty acid profiles of Nguni cattle milk. Forty-four Nguni cows with parities ranging from 1 to 13 were included in this study. The cows were grouped to three parity groups: parity group 1 (parity 1 to 5), parity group 2 (parity 6 to 9) and parity group 3 (parity 10 to 13). Samples of the milk were collected in a single day and the milk was analyzed using gas chromatography. Parity had no effect of proximate composition (fat, DMC and moisture %) on milk. The fatty acids (FA) present in the milk of the three parity groups were primarily palmitic (33.3 to 40.5%), oleic (16.3 to 20.3%), myristic (12.5 to 13.2%) and stearic (10.8 to 11.7%) acids, in decreasing order of proportion. Milk from parity group 3 cows contained significantly (p < 0.05) higher proportions of butyric, myristoleic, oleic, eicosenoic, conjugated linoleic acid (CLA), arachidonic and eicosopentaenoic acids when compared with th...
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A survey of diarrhoeagenic E. coli (DEC) was carried out on 21 minced beef and 21 boerewors (a traditional South African fresh sausage) samples purchased from 30% of butcheries in the Bloemfontein District of South Africa. The samples... more
A survey of diarrhoeagenic E. coli (DEC) was carried out on 21 minced beef and 21 boerewors (a traditional South African fresh sausage) samples purchased from 30% of butcheries in the Bloemfontein District of South Africa. The samples were cultivated on standard plate count agar for aerobic plate counts and chromocult coliform agar for coliform, E. coli, Salmonella enteritidis, and Shigella sonnei counts without enrichment. Diarrhoeagenic E. coli were isolated after enrichment in MacConkey broth followed by cultivation on chromocult coliform agar. The resultant E. coli colonies were selected and serotyped using the slide agglutination test for DEC. Enrichment enabled optimal recovery rates for E. coli and coliforms while Salmonella enteritidis and Shigella sonnei recovery rates decreased for both minced beef and boerewors. Eight (38.10%) minced beef samples were positive for DEC. The 8 positive samples consisted of 5 (23.81%) EPEC and 1 each (4.76%) of EIEC, EAggEC, and VTEC. A tota...
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Assessment of genetic variability with the help of suitable genetic parameters such as genetic coefficient of variation, heritability estimates, and genetic advance are absolutely necessary to start an efficient breeding program. Sixteen... more
Assessment of genetic variability with the help of suitable genetic parameters such as genetic coefficient of variation, heritability estimates, and genetic advance are absolutely necessary to start an efficient breeding program. Sixteen groundnut genotypes were evaluated for quantitative parameters. The crop was sown during 2015 wet season across four locations in Ethiopia. The experiment was laid out in an RCBD with two replications. The results of combined analysis of variance has shown that high heritability with high expected genetic advance were observed for stearic acid, arachidic acid, eicosenoic acid, lignoceric acid and oleic to linoleic acid ratio indicating the predominant role of additive gene action and the possibilities of effective selection for the improvement of these traits. However, heritability for oil content was low showing that direct selection for oil content is difficult; the possible improvement of oil content should be indirect selection through highly he...
Simple Summary Until now, the milk composition of impala and tsessebe has been unknown. Our study showed that the composition of impala milk was 5.56 ± 1.96% fat, 6.60 ± 0.51% protein, and 4.36 ± 0.94% lactose, and that of tsessebe milk... more
Simple Summary Until now, the milk composition of impala and tsessebe has been unknown. Our study showed that the composition of impala milk was 5.56 ± 1.96% fat, 6.60 ± 0.51% protein, and 4.36 ± 0.94% lactose, and that of tsessebe milk was 8.44 ± 3.19%, 5.15 ± 0.49%, and 6.10 ± 3.85%, respectively. The fatty acid composition and protein properties also differed. The data of these two species were subjected to an interspecies comparison with 13 other antelope species by statistical methods. This showed that the milk of tsessebe is similar to that of its relatives of the Alcelaphinae sub-family. Although the impala is a close relative of the Alcelaphinae, its milk composition finds comparison with a different sub-class, the Hippotraginae. The information contributes to the phylogenetic properties of milk and milk evolution. Abstract The major nutrient and fatty acid composition of the milk of impala and tsessebe is reported and compared with other Bovidae and species. The proximate c...
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Abstract Since high salt intake is regarded as unsafe for human health, the South African Department of Health released regulations for a stepwise lowering of salt content in certain food products. This can, however, negatively impact on... more
Abstract Since high salt intake is regarded as unsafe for human health, the South African Department of Health released regulations for a stepwise lowering of salt content in certain food products. This can, however, negatively impact on the safety and shelf-life of food products. No studies have yet been performed on the effect of salt reduction/replacement on the microbial communities in fresh processed meat sausage such as Boerewors, when inoculated with E. coli ATCC® 25922. This study used community-level physiological profiling, employing the Biolog™ Ecoplates™. The reactions of the microbial communities to 31 carbon compounds were statistically evaluated. The treatment with no added salt (NC), showed the highest growth rate and maximum population size when compared to the treatments containing salt and replacers. The average well colour development and Shannon richness indicated that the potassium chloride treatment was significantly more efficient in controlling the growth of the microbial communities when compared to the NC. With the single carbon oxidation, the K600 and N600 were comparable to each other in controlling the growth of the bacterial communities. The PCA plot indicated that there was a reduction in the functional diversity of microbial communities and E. coli in Boerewors with higher salt content.
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The combined data of milk composition of 14 African elephants over 25 months of lactation are presented. The milk density was constant during lactation. The total protein content increased with progressing lactation, with caseins as the... more
The combined data of milk composition of 14 African elephants over 25 months of lactation are presented. The milk density was constant during lactation. The total protein content increased with progressing lactation, with caseins as the predominant protein fraction. The total carbohydrates steadily decreased, with the oligosaccharides becoming the major fraction. Lactose and isoglobotriose reached equal levels at mid lactation. The milk fat content increased during lactation, as did the caprylic and capric acids, while the 12 carbon and longer fatty acids decreased. The fatty acid composition of the milk phospholipids fluctuated, and their total saturated fatty acid composition was low compared to the triacylglycerides. The milk ash and content of the major minerals, Na, K, Mg, P, and Ca, increased. Vitamin content was low, Vitamin E occurred in quantifiable amounts, with traces of vitamins A, D3, and K. The energy levels of African elephant milk did not change much in the first ten...
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The study investigated the nutritional value of M. azedarach Linn. (Meliaceae family) leaf meal (MALM) as an alternative protein source for beef cattle. In a completely randomised design (CRD), 18 Nguni x Brahman 18 - 20 months old steers... more
The study investigated the nutritional value of M. azedarach Linn. (Meliaceae family) leaf meal (MALM) as an alternative protein source for beef cattle. In a completely randomised design (CRD), 18 Nguni x Brahman 18 - 20 months old steers were randomly offered 3 iso-energetic and iso-nitrogenous dietary treatments with, respectively, 0% (Control), 15% and 30% MALM replacing broiler litter, each with 6 replicate animals, for 90 days. Feed intake (FI), water intake (WI), slaughter weight, body weight gain (BWG), feed conversion efficiency (FCE) and kidney fat depot fatty acid (FA) composition as well as health-related FA totals, ratios and other indices were measured. Results showed MALM contained rather high CP (290.0 g/kg DM), CF (170 g/kg DM), EE (78.1 g/kg DM) and ash (77.5 g/kg DM) contents. Also, dietary supplementation with MALM increased BWG and FCE (P < 0.01) but had no effect on FI, WI and slaughter weight of steers (P > 0.05). Also, it increased kidney fat margaric ac...
Research Interests:
The associations between the traits of interest in plant breeding are commonly evaluated by means of phenotypic, genotypic and environmental correlations, and through path coefficient analysis that shows direct and indirect cause and... more
The associations between the traits of interest in plant breeding are commonly evaluated by means of phenotypic, genotypic and environmental correlations, and through path coefficient analysis that shows direct and indirect cause and effect relationship. Sixteen groundnut genotypes (including local check) were evaluated for quantitative parameters. The crop was sown during 2015 wet season across four locations in Ethiopia. The experiment was laid out in Randomized Complete Block Design (RCBD) with two replications. The results indicated that genotypic correlations were higher than the phenotypic and environmental ones. The grain yield (kg/ha) has presented positive and significant genetic correlation with PWP, SWP and 100SW. Genetic correlations of oil content with agro-morphological traits and oil quality parameters were shown that oil content was significant and positively correlated with pod weight per plant (PWP) and seed weight per plant (SWP) showing that possibility of indire...