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Objective: To determine the in vitro digestibility and gas production, and to estimate the methane emissions from Kikuyu grass pastures, and Kikuyu grass overseeded with rye. Design/methodology/approach: Two pastures were assessed. One was the subtropical grass Kikuyu (Cenchrus clandestinus) (KY), and the other was Kikuyu grass plus overseeding with rye (Secale cereale) (KYCEN), both associated with white clover (Trifolium repens cv. Ladino). Sample collection was in June and July 2021. In vitro digestibility of dry matter (MS), organic matter (MO), and Neutral Detergent Fibre (FDN), as well as the methane emissions were estimated. The in vitro digestibility and gas production variables were analysed with a split-plot experimental design, and the methane emission variables were analysed with a doble cross-over design. Results: There were no significant differences between treatments for dry matter (MS), organic matter (MO) or Neutral Detergent Fibre (FDN) in vitro digestibility, nor in methane emissions (P>0.05). Limitations on study/implications: The in vitro assessment of digestibility, gas production and the estimation of methane emissions of Kikuyu grass pastures and Kikuyu plus rye enable the implementation of feeding strategies for small-scale livestock production systems that do not only benefit the farmers but also the environment. Findings/conclusions: It is concluded that Kikuyu grass pastures and Kikuyu with rye are a viable feeding option for small-scale dairy systems. [ABSTRACT FROM AUTHOR]

Invasive plants are a threat to natural ecosystems worldwide, with urban wetlands being some of the most susceptible and highly modified environments of all. The tiger snake (Notechis scutatus) is a top predator that persists in urban wetlands of south-western Australia, many of which have been degraded by introduced kikuyu grass (Cenchrus clandestinus). To evaluate the potential impact of kikuyu grass on habitat quality for tiger snakes we quantified the structural features of habitats within wetlands degraded by kikuyu grass and compared them to wetlands with native vegetation. We also examined tiger snake prey availability, assessed predation risk for juvenile snakes using clay models, and measured the thermal quality of the vegetation. Proliferation of kikuyu grass has reduced habitat structural heterogeneity by reducing available bare ground and increasing vegetation density. This homogenisation of habitat structure had little effect on the predation risk for juveniles or the thermal properties of tiger snake shelter sites; however, one key prey species, the motorbike frog, had significantly lower abundance in the most impacted habitat. Habitat types with more structural complexity also offered tiger snakes more stable thermal regimes and lower predation risk. These findings indicate that the current extent of kikuyu grass invasion offers overall similar habitat quality for tiger snakes to native vegetation and may contribute to their persistence in urban wetlands; however, both tiger snakes and their anuran prey may benefit from increased habitat structural complexity. [ABSTRACT FROM AUTHOR]

Summary: During a survey of soil nematodes in 2022, a free-living bacterivorous nematode, described here as Mesorhabditis sudafricana n. sp., was discovered in association with kikuyu grass in Limpopo Province, South Africa. The new species was distinguished by a relatively long body (716-815 μ m in females and 605-689 μ m in males), long spicules (61-66 μ m), and gubernaculum (22-24 μ m) and a short tail (15-20 μ m in females and 18-21 μ m in males). The vulva is positioned posteriad (93-95% of body length), and the distance from vulva to anus is long (1.5-1.9 times tail length). Additionally, the new species bears seven lateral field incisures and a peloderan bursa with the genital papillae in arrangement 2/3+ph+1+3, being two precloacal and eight postcloacal. The 28S rDNA BlastN showed 94% similarity with an unidentified Mesorhabditis (deposited as Bursilla (EF990722). By contrast, the ITS rDNA BlastN showed 82% similarity with Mesorhabditis paucipapillata (MT710243). The phylogenetic analysis of 28S and ITS rDNA placed the new species separately from the other Mesorhabditis. Description, measurements, illustrations and SEM micrographs for M. sudafricana n. sp. are provided. [ABSTRACT FROM AUTHOR]

Context. The kikuyu grass (Cenchrus clandestinus) is native to Africa and is one of the most widely used grasses for forage feeding in dairy regions around the world. Aims. To obtain the first set of microsatellite markers for the population genetics study of kikuyu grass, using nextgeneration sequencing technology (Illumina MiSeq). Methods. Sixty loci were evaluated, in which a subset of 12 loci were selected to be used for a complete population analysis in 108 samples of kikuyu, and were grouped in to three zones of Colombia. The three approaches with which the genetic structure was evaluated. Key results. Obtained same tendency of grouping reflects a low genetic differentiation, specifically evidencing differences between the northern zone of Antioquia and the zones that comprise the other territories of Colombia. Conclusions. These reads of microsatellite loci help to complement the information on the genetic structure of the populations of the kikuyu, and will be useful for the characterisation and evaluation of the diversity of germplasm in other parts of the world. Implications. The set of microsatellite markers developed has a species-specific reproducibility and could be used for studies in other Cenchrus individuals and particularly in future investigations with Kikuyu grass. Likewise, this research presents findings in a broad context and relates them to other pasture species. [ABSTRACT FROM AUTHOR]

Intensive grazing increases the profitability and sustainability of small-scale dairy systems by reducing feeding costs. Kikuyu grass is a subtropical species from East Africa that has similar performance compared with temperate grasses when grazed by dairy cows in these systems during the summer rainy season but reduces growth and quality at low temperatures, when temperate species may have an advantage. The objective was to evaluate intensive grazing of kikuyu pastures (KYKY) alone or in association with two varieties of endophyte-free tall fescue, TF-33 (TF33) and Cajun II (CAJN), during the summer–autumn transition period when low temperatures set in, by lactating cows in small-scale dairy farms. Pasture variables were analysed with a split-plot design for sward height, net herbage accumulation and chemical composition, in vitro digestibility of organic matter, and estimated metabolisable energy content of herbage and concentrate. Experimental design for animal variables was a 3 × 3 Latin Square repeated three times with nine Holstein cows and 14 days experimental periods. Cows received 4.65 kg DM/day of a 16% CP commercial concentrate. Milk yield and composition, live weight, and body condition score were recorded. There were no significant differences (P > 0.05) for sward height and net herbage accumulation, nor for important components of chemical composition of herbages. There were no significant differences (P > 0.05) for milk yield (19 kg/cow/day) and composition, although differences (P < 0.05) were detected for live weight and body condition score. The conclusion is that there is no advantage of associating tall fescue with kikuyu in summer–autumn transition period for small-scale dairy systems. [ABSTRACT FROM AUTHOR]

Introduction: The sustainable production of pastures has become a fundamental challenge for the livestock sector where research with plant growth-promoting rhizobacteria as a viable solution, has nearly not been reported. Objective: In this study, we aimed to examine the potential to stimulate growth in Pennisetum clandestinum grass using four isolated bacterial strains from soils obtained from a Colombian tropical silvopastoral system. Methods: We previously identified genetically the strains and characterized two plant growth promoting activities. In addition, we evaluated the growth-promoting effect of the strains in Kikuyo grass under greenhouse conditions. Results: We found that the four bacterial strains were phylogenetically associated with Klebsiella sp. (strains 28P and 35P), Beijerinka sp. (37L) and Achromobacter xylosoxidans (E37), based on partial 16S rRNA gene sequencing. Moreover, the in vitro biochemical assays demonstrated that the strains exhibited some plant growth promoting mechanisms such as 1-aminocyclopropane-1-carboxylic acid deaminase activity and indole compound synthesis. Notably, bacterial inoculation under greenhouse conditions showed a positive influence on P. clandestinum growth. We found a significant (P < 0.05) effect on root and shoot length and shoot dry weight. Shoot length increased by 52 % and 30 % with 37L and 35P compared to those without inoculation treatment. Similarly, the use of 37L and 28P raised shoot dry weight values by 170 % and 131 %, respectively. In root development, inoculation with strains 37L and E37 increased root length by 134 % and 100 %, respectively. Conclusion: Beijerinckia sp. 37L was the most effective of the four strains at increasing P. clandestinum biomass and length. [ABSTRACT FROM AUTHOR]

• Kikuyu grass grew well under irrigation with secondary treated wastewater. • Remarkable kikuyu grass yield achieved in the absence of any type of fertiliser. • Advanced treated wastewater was not suitable for use as irrigation water. • Soil pH irrigated with advanced treated wastewater increased considerably. • Soil salinity increased when irrigated with different types of treated wastewaters. Treated wastewater, also called as recycled water, is a reliable source of water for various non-potable purposes. One of the most common uses of recycled water has been for irrigation. A soil column study was carried out for a period of one year. The objective of this study was to determine the effect of irrigation using two different types of treated wastewaters on kikuyu grass (Pennisetum clandestinum) production in the absence of any kind of chemical fertilisers. Soil irrigated with secondary treated wastewater, MBR (Membrane Bioreactor), resulted in highest annual grass production (16,241 kg of dry-matter per hectare (kg DM/ha)) compared to advanced treated wastewater, IDAL (Intermittently Decanted Aerated Lagoon), and tap water (TW) with annual yields of 7028 and 14,216 kg DM/ha, respectively. Irrigation waters, soil extracted waters and soil samples from different depths of the columns were analysed. Sodium adsorption ratio (SAR), exchangeable cations, electrical conductivity (EC) and pH changed in each experimental column due to different characteristics of applied irrigation waters. The results indicate that high contents of nitrogen and phosphorous in MBR water compensated for the presence of moderate salinity level that contributed to the higher production of grass compared to other two types of irrigation waters. The increase in pH from initial amount of 5.9 to 7.3 in top part of IDAL-irrigated soil may have resulted in low grass yield. This pH increase can be attributed to the high concentrations of cations in the irrigation water in the lack of sufficient amount of nitrogen. Overall, the study demonstrated that a relatively higher grass yield in the absence of any types of fertilisers is possible with recycled water irrigation using secondary treated wastewater. Further, the recycled water irrigation with advanced treatment of wastewater, while costs more, does not result in increased yield benefits. [ABSTRACT FROM AUTHOR]

Highlights • All pasture meters accurately estimate pasture mass. • Laser sensor was more accurate than other pasture meters estimating pasture mass. • Pasture density measured with the laser improved accuracy of pasture mass estimates. Abstract Pasture meters are typically calibrated to estimate total pasture mass (TPM). Recent studies have shown that animal productivity was driven by the level of utilisation of the top leafy stratum (TLS) rather than the TPM. A study of kikuyu (Pennisetum clandestinum) pasture conducted on two farms located in southeast Queensland, Australia assessed whether pasture mass of the TLS, bottom stemmy stratum (BSS) and TPM can be more accurately estimated by using not only pasture surface height but also pasture density derived from height data captured by a laser sensor. The results indicated that there was a notable improvement of the pasture mass estimates when density was included in the calibration equations. The study also compared the accuracy of the pasture mass estimates between the laser sensor and mechanical pasture meters (rising plate meter and ruler). The results indicated that all devices provided reasonable estimates of pasture mass for TLS, BSS and total (R2 ≥ 0.75). However, pasture mass was estimated with a slightly higher level of accuracy when using the laser sensor in comparison with the other pasture meters, particularly for the top leafy stratum (R2 = 0.81 vs R2 ≤ 0.77). [ABSTRACT FROM AUTHOR]

Dried apple pulp (DAP) is a by-product of the apple juice industry. It has a comparable ME and CP content to maize but has a higher NDF content. It has been used as a substitute to maize with success in various TMR systems, offering an affordable alternative to maize. The aim of the study was to determine whether the replacement of maize with DAP would be beneficial to milk production and rumen health of Jersey cows grazing kikuyu pasture. Seventy two lactating Jersey cows were blocked according to milk yield, days in milk and lactation number. Cows within blocks were randomly allocated to one of four treatments. Treatments were: 0% DAP inclusion (AP 0), 25% DAP inclusion (AP 25), 50% DAP inclusion (AP 50) and 75% DAP inclusion (AP 75). Cows received 6 kg as is/day of the allocated concentrate in the milking parlour. Cows of all four treatments strip grazed kikuyu-ryegrass pasture, as one group, over an area of 8.6 ha. A rising plate meter was used to estimate pasture DM yield pre- and post-grazing and manage the allocation of pasture. Pasture samples and feed samples were collected on a weekly basis, dried at 60° C for 72 h and pooled every two weeks. An additional eight ruminally cannulated cows were used and were subjected to a four period crossover design with a 14 day adaptation period between treatments. Rumen pH, pasture DM and NDF degradability and VFA profile were determined. Treatment did not have an effect on milk yield; however, there was a linear decrease in 4% FCM and fat yield as the level of DAP inclusion in the diet increased. Cows receiving the AP 0 concentrate supplement yielded 0.9 and 1.2 kg more 4% FCM than cows on the AP 50 and AP 75 concentrate supplements (P < 0.001), respectively. Treatment had no effect on milk composition, except for the lactose content which was lower for cows receiving the AP 0 concentrate supplement (P < 0.001). Average rumen pH was lower for cows receiving the AP 75 concentrate supplement (P < 0.001); however, treatment did not affect the VFA profile or pasture DM and NDF degradability. It was concluded that the replacement of maize with DAP for cows grazing kikuyu pasture is a viable option; however, the possible decrease in 4% FCM yield should be taken into consideration. [ABSTRACT FROM AUTHOR]

The aim of this study was to evaluate the effects of the association between red clover (RC; Trifolium pratense ) and a tropical grass (kikuyu grass) on the proteolysis of ensiled material and the in vitro degradation of protein and organic matter. Red clover and kikuyu grass were ensiled in the following proportions: 0:1000, 250:750, 500:500, 750:250, and 1000:0 g/kg of dry matter (DM). The fraction of rapidly degradable protein, the ammonia nitrogen (NH 3 -N) content of the silo, the in vitro protein degradation, and the degradation rate decreased linearly (P < 0.001) as the RC content in the ensiled material increased. Cumulative gas production after 24 h incubation showed a positive quadratic effect when RC was increased to 500 g/kg (P < 0.001). The silages with the highest RC content reduced proteolysis more effectively during ensiling and ruminal fermentation. Inter-species synergistic effects positively affected in vitro gas production, which was optimal when RC and kikuyu grass were ensiled in the same proportions as that of total DM. [ABSTRACT FROM AUTHOR]

Soil quality of tillage systems receives much attention worldwide, although few studies attempt to link soil quality to yield. Partial least-squares regression analysis is a suitable method to construct predictive models around plural, highly collinear factors, such as soil quality and its effects on yield. This study aimed at identifying the soil quality properties which best model pasture herbage yield by relating soil quality indicators with variations in yield as a result of soil disturbance caused by tillage. The study was conducted on kikuyu ( Pennisetum clandestinum) over-sown with annual ryegrass ( Lolium multiflorum) using different tillage methods. Tillage methods involved over-sowing kikuyu with ryegrass using a minimum-tillage seed drill, eradication of kikuyu with herbicide and ryegrass sown with a minimum-tillage planter, shallow and deep disturbance, and a control. Most changes in soil quality indicators as a result of soil tillage were observed shortly after tillage and occurred mostly at the 0-100 mm soil layer. Few of these effects were still visible 420 d after tillage. Microbiological indicators changed most in response to the treatments, but unlike the chemical and physical indicators, microbiological indicators have no causal link to pasture production. The contribution of individual soil quality indicators to variance in pasture productivity could not be isolated and should thus be seen as complex processes which affect yield. Although mechanisms of how some soil quality indicators affect yield is clear, more research is required to determine mechanisms of how a combination of multiple soil quality indicators affects yield. [ABSTRACT FROM AUTHOR]

This paper aims at dispelling the misconception that the prevalence of agro-pastoral conflicts in Menchum Division of North West Cameroon is because stakeholders have no interest in resolving them. Such disputes have been a common feature in the country where economic resources generate protracted clashes not only between ethnic groups, villages and individuals, but also over the choices of economic activity. From simple crop damage, the opposition between farmers and graziers has been taking many forms, ranging from daily quarrels, frequent exchange of blows, mob demonstrations and litigation, to the use of mystical powers and conventional weapons. Although these struggles are common throughout the division, Esu, Kuk, Mmen and Wumhave singled themselves out as hotbeds. The consequences of these clashes are reflected in almost all spheres of life, including the economy, education, ethnicity, gender, health, human rights, justice, nutrition, peace and politics. In the face of these catastrophic effects, the administration and people of Menchumhave have been trying in many ways to curb the disputes, albeit without any remarkable success. In 1947, Cattle Control Rules were instituted by Native Authorities who, unfortunately, lacked the legal basis to enforce any decisions and so the 1962 Control of Farming and Grazing Law was brought into force. But it also proved unworkable because stakeholders openly and obstinately refused to obey its provisions. Even the 1978 Presidential Decree creating a statutory organ (the Farmer Grazier Commission) for the settlement of conflicts has remained a toothless bulldog. Other administrative policies, such as demarcation of land, introduction of mixed farming and the barbed wire scheme intended to facilitate peaceful coexistence between the two rival activities, were implemented without any remarkable success. The holding of meetings with stakeholders, the proposals made by the World Food Organization (FAO) in 1962 and the laying down of resolutions by commissions of inquiry like the Nseke Commission (1973) and Koumpa Issa Commission (2003) were other unsuccessful measures aimed at resolving disagreements. Instead of dissipating, conflicts rather escalated, becoming acute and chronic. [ABSTRACT FROM AUTHOR]

The introduction of kikuyu (Cenchrus clandestinus (Hochst. ex Chiov.) Morrone) into Australia in 1918 has seen it become established and adapted to several geographic regions in a wide range of ecologies and environmental situations. After it naturalised to local conditions, researchers and farmers recognised the value of kikuyu in marginal and previously unproductive sites, where forage quality and quantity made this species popular with dairy farmers and pastoralists. Its versatility and prostrate, mat-forming characteristics also led to the adoption of kikuyu by local governments, homeowners and sporting organisations in urban environments as turf. Kikuyu has the ability to alleviate soil contamination and remediate soils, thus enhancing the use of previously unproductive land. However, the aggressive growth habit of the species, considered a problem in certain regions of the world, has led to a noxious weed classification in some states of the USA. This review includes information on expected changes to world agricultural and urban environments and the potential expanded role of kikuyu. The origin of kikuyu grass, genetic variability, tolerances to soil salinity and drought, and potential for genetic improvement are also discussed. [ABSTRACT FROM AUTHOR]

O experimento foi conduzido a campo com o objetivo de determinar as frações de fósforo (P) em gramíneas forrageiras tropicais, aos 35 dias de idade, sob fontes e doses de P. Foi utilizado o delineamento experimental em blocos ao acaso, com três repetições, com os tratamentos dispostos em um esquema de parcelas subsubdivididas, sendo alocadas nas parcelas as gramíneas (capim-coastcross, capim-florona e capim-quicuio); nas subparcelas as fontes de P (Superfosfato Triplo, Fosfato Reativo, Arad e Fosfato Natural, Araxá) e nas subsubparcelas as doses de P (0, 40, 80 e 120 kg/ha de P2O5). As variáveis estudadas foram as frações de P, P total solúvel, P inorgânico e P orgânico. O capim-quicuio apresentou maior (PThe work was carried out with the objective to determinate fractions of phosphorus (P) in the tropical forage grasses, at 35 days of age, submitted to sources and doses of P. The experimental design was a randomized complete block, in split split plot scheme, with three repetitions, being allocated in the plot the grasses (coastcross bermudagrass, florona stargrass and kikuyu grass); in the subplot the sources of P (Triple superphosphate; Reactive phosphate, Arad and Nature phosphate, Araxa) and, in the subsubplot, the doses of P (0, 40, 80 and 120 kg/ha of P2O5). The studied variables were soluble total P- Pt, inorganic P- Pi and organic P- Po. The kikuyu grass shown lower (P

N-alkanes, long-chained saturated hydrocarbons occurring in plant cuticles, were used for estimating grass intake in fast-growing, free-range broilers. A total of 1440 as hatched mixed sex Cobb 500 broilers were equally divided between one of four experimental treatments in a 2 by 2 factorial arrangement involving conventional (barn) or free-range (barn and range access) production systems and diets (crude protein: 21%, metabolisable energy: 13 MJ/K) with or without in-feed antibiotic (Zinc Bacitracin: Albac®G150 antibiotic feed premix, Pfizer Australia Pty Ltd, Sydney, NSW, Australia). Day-old chicks were randomly allocated to 48 pens (12 replicates/treatment) with 30 birds in each pen. Chicks were assigned to treatment diets on Day 1 while free-range access was available to birds from Day 21 onwards. Alkane concentrations in litter were measured and compared with alkane profiles of the intake components (grass, diet pellets and woodchip). Correction for incomplete recovery followed by estimation using a non-negative least square procedure resulted in calculation of total grass intake from the range area. Kikuyu grass consumption was estimated to be 13.5-14.7% of total 'as-fed' intake, equating to 6.34-6.78 g of grass per bird per hour of range access in this study. Taking into account grass consumption, this resulted in a significant increase in feed intake by 8.7-8.9% (P < 0.01) and feed conversion ratio from 2.30 to 2.54 points (P < 0.01). It can be concluded that broilers reared under free-range conditions eat a substantial quantity of grass. However, the nutrient profile of grass is not complementary to the formulated ration and its consumption is likely to lead to an array of nutritional changes for the bird, thus affecting performance. [ABSTRACT FROM AUTHOR]

A new species of tarsonemid mite, Steneotarsonemus hippodromus sp. nov., is described from kikuyu grass Pennisetum clandestinum (Poaceae). The new species is the fifth species of the subgenus Steneotarsonemoides. Keys to the subgenera of Steneotarsonemus and species of Steneotarsonemoides are provided, as is a list of species in each subgenus of Steneotarsonemus. [ABSTRACT FROM AUTHOR]

Bauxite residue, a waste product of aluminium processing operations is characterised by high pH, salinity and exchangeable sodium which hinders sustainable plant growth. The aim of this study was to investigate the uptake form, optimum application rate and timing of nitrogen fertiliser to improve bauxite residue characteristics for plant growth. Kikuyu grass was grown in plastic columns filled with residue sand/carbonated residue mud mixture (20:1) previously amended with gypsum, phosphoric acid and basal nutrients. The experiment was set up as a 4 × 4 factorial design comprising four levels of applied nitrogen (N) fertiliser (0, 3, 6 and 12 mg N kg − 1 residue) and four frequencies of leaching (16, 8 and 4 day intervals). We hypothesised that the use of ammonium sulfate fertiliser would increase retention of N within the rhizosphere thereby encouraging more efficient fertiliser use. We found that N uptake by kikuyu grass was enhanced due to leaching of excess salts and alkalinity from the residue profile. It was also concluded that biomass production and associated N uptake by kikuyu grass grown in residue is dependent on the type of fertiliser used. [ABSTRACT FROM AUTHOR]

Kikuyu (Pennisetum clandestinun or Kikuyuocloa clandestina) silage fermented with three additives. The objective of the study was to evaluate the characteristics of kikuyu grass silage with high humidity and the bromatologic quality when adding three different additives. These were added at three levels: molasses: 0, 2, and 4%, ground corn and citrus pulp: 5, 7 and 9% on a dry basis on the whole forage, fresh chopped and compacted in plastic bags. The experiment was conducted in 2010 at the El Pizote dairy farm, located in San Ramón, Tres Ríos, Cartago, Costa Rica. The experimental period lasted 77 days. Averages of 14.10%, 13.75%, 13.71% DM, 8.20%, 7.38%, 7.36% CP, 77.48%, 79.51%, 79.07% NDF, 39.22%, 40.12%, 39.68 % of FAD, 38.26%, 39.39%, 39.39% hemicellulose, 32.79%, 33.47%, 33.26% cellulose, 6.43%, 6.66%, 6.42% lignin, 2.23%, 1.89%, 2.04% EE and 11.53%, 11,74% , 11, 65% of total ash for silage with molasses, ground corn and citrus pulp respectively were obtained. Differences (p<0.05) were found in the amount of effluent according to the additive and the addition level. High humidity of kikuyu grass can cause that the effluents produce since the beginning until obtaining the maximum accumulation inside the bag, after 60 to 80 días of silage. That is why the bag has to be checked periodically and, if possible, drain the liquid effluents generated to avoid the process of deterioration. [ABSTRACT FROM AUTHOR]

Objective. Determine the population density of cellulolytic bacteria, Butyrivibrio fibrisolvens and the concentration of vaccenic acid, by supplementing diets consisting of kikuyu grass (Pennisetum clandestinum Hoechst. Ex Chiov.) as base ingredient, together with cassava flour and biomass (effluent from ethanol production) in rumen simulator-Rusitec. Materials and methods. Four treatments (T) were evaluated, these were composed as: T1/Control 1: 100% kikuyu grass with a total protein intake of 23.9%, T2: a mixture of 70% kikuyu grass, 20% biomass and 10% cassava flour with a total protein intake of 19.4%; T3/Control 2: 100% kikuyu grass, with a 17.8% protein intake and T4: 70% kikuyu grass, 20% biomass and 10% cassava flour with a 15.3% protein intake. One and two-way variance analysis was made and the Pearson correlation coefficient was determined. Results. An increase was observed in the population density of viable cellulolytic bacteria (CFU/ml) and B. fibrisolvens statistically significant (p<0.005) with treatment T2, in contrast to T1, T3 and T4 treatments. In addition, there was a significant increase in the concentration of vaccenic acid (mg/L) in the ruminal content in Rusitec with the same treatment (T2). Conclusions. Results obtained in this ruminal simulation study are evidence to the benefits of kikuyu grass together with cassava flour and biomass diet implementation on the growth of ruminal cellulolytic and B. fibrisolvens bacteria, as well as on the production of vaccenic acid. The study also suggests the nutritional potential that such supplements could provide to grazing bovine feeding. [ABSTRACT FROM AUTHOR]

Distributions of invasive alien species (IAS) are well documented all over the world, and roads are considered one of the main means by which IAS spread. Bolivia is one of a few countries for which there are no such studies. For this reason, we determined the number of exotic plant species in the vicinity of roads near the city of La Paz, Bolivia. We distinguish two types of roads, paved and gravel roads, and in their vicinity, we studied the floristic composition in three regions, differing mainly in altitude: high Andes, puna grassland and dry valley. We found three exotic species in the vicinity of roads in the high Andes, five in puna grassland and 10 in the dry valley. We found 13 exotic species along gravel roads and nine along paved roads, whilst there was a trend for such species to be more abundant close to the roads than further away. Pennisetum clandestinum was the most frequently recorded exotic species in all regions and associated with both types of roads. The results indicate that exotic species are quite frequent along roads in Bolivia and present a potential threat as invasive species. Therefore, it may be necessary to take measures to prevent IAS from spreading further. [ABSTRACT FROM AUTHOR]

The use of plant growth regulators (PGRs) and biostimulants to enhance phytoextraction is gaining popularity in phytoremediation technology. This study investigated the stimulatory effects of smoke-water (SW), a smoke-derived compound karrikinolide (KAR1) and other known plant growth regulators (PGRs) [gibberellic acid (GA3), kinetin (Kin) and indole-3-butyric acid (IBA)] to enhance the phytoextraction potential ofPennisetum clandestinum. Pennisetum clandestinumseedlings were grown for 10 weeks in vermiculite using Hoagland's nutrient solution and were treated with cadmium (Cd) (2, 5, and 10 mg L−1) and SW, KAR1and PGRs. KAR1exhibited positive effects on shoot and root dry weight (140 and 137 mg respectively) at the highest concentration of Cd (10 mg L−1) compared to all the other treatments. KAR1and SW treatments used in the present study significantly improved the phytoextraction potential ofP. clandestinum(602 and 575 mg kg−1respectively) compared to the other tested PGRs. This is the first report on the use of SW and KAR1to enhance phytoremediation potential inP. clandestinum.Further studies are needed to elucidate the exact mechanisms of smoke constituents involved in phytoextraction potential of plant species. [ABSTRACT FROM AUTHOR]

Restoring degraded mesic-montane forests represents a major challenge in maintaining functioning ecosystems throughout the tropics. A key example of this lies in Hawai'i, where restoring native koa ( Acacia koa, A. Gray) forests are a top conservation and forestry priority because of the critical habitat and high-value timber products that they provide. Efforts to restore koa forests, however, are directly impeded by extensive, non-native kikuyu grass ( Pennisetum clandestinum Hochst. ex Chiov.) swards occupying deforested montane landscapes. In this study, we implemented a combination of grass suppression and selection of koa seedling stocktypes to measure outplanting performance in a naturalized site on the island of Maui. Seedlings were grown in a nursery in two root container sizes (111 and 207 cm) and subsequently outplanted into grass-dominated plots that were either untreated or suppressed with a high-rate herbicide combination of imazapyr and glyphosate (1.7 kg a.i. ha, respectively), 30 days prior to planting. Across all treatments, seedling survival was high (>95 %). Thirty months after planting, trees from the larger stocktype had significantly greater growth in height and root-collar diameter. Initial grass suppression resulted in trees that were 34 % taller with 66 % larger root-collar diameters after 30 months. Herbicide treated plots also had significantly higher leaf area indices (2.6 vs. 1.8 m m), indicative of higher photosynthetic capacity and canopy closure. Grass suppression increased soil temperature along with soil moisture in the first year followed by a dramatic drop in moisture corresponding to large growth responses by koa seedlings after the first year. These results demonstrate how the combination of fundamental silvicultural practices in the nursery and on the outplanting site can accelerate tree growth to meet restoration goals in shorter time intervals. This is a first report of koa (a leguminous species) tolerance to a high-rate, pre-plant application of the herbicide active ingredient imazapyr. [ABSTRACT FROM AUTHOR]

Objective. To evaluate the effect of Kikuyu grass (Pennisetum clandestinum) harvested at two different ages and three forage: concentrate supplement ratios (F/C) on methane (CH4) production, dry matter digestibility (DMD), and fermentation profile using the in vitro gas production technique. Materials and methods. six treatments, resulting from the combination of pasture age (30 or 60 days) and F/C (100/0, 75/25, or 50/50) were evaluated using a 2x3 factorial design. The response variables were measured 6, 12, 24 and 48 hours after incubation. A repeated-measure over time design was used to analyze the data, and differences between means were determined with the LSMEANS procedure of SAS. Results. the youngest grass (30 days) was more digestible, produced less CH4 per gram of digestible dry matter (dDM) and more total volatile fatty acids (VFA) compared to the oldest grass (60 days; p <0.05). Reductions of the F/C ratio increased DMD and CH4 production per gram of dDM (p<0.05) but had no significant effect on VFA concentration (p>0.05). Conclusions. under in vitro conditions and pH close to neutrality, the older grass reduces DMD and increases CH4 production per gram of dDM, while a F/C reduction increases DMD and CH4 production per gram of dDM, which differs with reports conducted in vivo. [ABSTRACT FROM AUTHOR]

The effects of three treatments of fibrolytic enzymes (cellulase from Trichoderma longibrachiatum ( CEL), xylanase from rumen micro-organisms ( XYL) and a 1:1 mixture of CEL and XYL ( MIX) on the in vitro fermentation of two samples of Pennisetum clandestinum (P1 and P2), two samples of Dichanthium aristatum (D1 and D2) and one sample of each Acacia decurrens and Acacia mangium (A1 and A2) were investigated. The first experiment compared the effects of two methods of applying the enzymes to forages, either at the time of incubation or 24 h before, on the in vitro gas production. In general, the 24 h pre-treatment resulted in higher values of gas production rate, and this application method was chosen for a second study investigating the effects of enzymes on chemical composition and in vitro fermentation of forages. The pre-treatment with CEL for 24 h reduced (p < 0.05) the content of neutral detergent fibre ( NDF) of P1, P2, D1 and D2, and that of MIX reduced the NDF content of P1 and D1, but XYL had no effect on any forage. The CEL treatment increased (p < 0.05) total volatile fatty acid ( VFA) production for all forages (ranging from 8.6% to 22.7%), but in general, no effects of MIX and XYL were observed. For both P. clandestinum samples, CEL treatment reduced (p < 0.05) the molar proportion of acetate and increased (p < 0.05) that of butyrate, but only subtle changes in VFA profile were observed for the rest of forages. Under the conditions of the present experiment, the treatment of tropical forages with CEL stimulated their in vitro ruminal fermentation, but XYL did not produce any positive effect. These results showed clearly that effectiveness of enzymes varied with the incubated forage and further study is warranted to investigate specific, optimal enzyme-substrate combinations. [ABSTRACT FROM AUTHOR]

The aim of the study was to determine the effect of different inclusion levels of palm kernel expeller (PKE) in dairy concentrates for grazing Jersey cows on lactation performance and rumen fermentation patterns. Forty-eight multiparous, Jersey cows, grazing kikuyu-ryegrass during spring, were blocked according to 4% fat corrected milk, days in milk and lactation number and randomly allocated to three treatments based on PKE level in the concentrate. The PKE inclusion in the control (C), low PKE (LP), and high PKE (HP) treatment concentrates was 0, 200, and 400 g/kg, respectively, and was fed for a 60 d period, preceded by a 21 d adaptation period. The PKE partially substituted some of the maize and soybean in the concentrate. Additionally, eight rumen-fistulated, lactating dairy cows were randomly allocated to the C and HP treatment in a two period cross-over design. Cows received 6 kg (as is) concentrate per day divided over two milkings and strip-grazed pasture as one group. Milk yield and milk fat content did not differ between treatments and were 21.3, 21.3 and 20.7 kg/cow/d and 46.3, and 46.5, and 46.6 g/kg for the C, LP and HP treatment, respectively. Milk protein, milk urea nitrogen, body weight and body condition score did not differ between cows on all treatments. Total volatile fatty acid, mean ruminal pH, ammonia nitrogen, and in situ pasture dry matter and neutral detergent fibre degradability did not differ between cows on all treatments. The acetic to propionic acid ratio was higher (P=0.006) for cows receiving treatment HP compared to cows receiving treatment C (3.40 vs. 3.22). It was concluded that PKE can sustain milk yield and milk fat components at a level of up to 400 g/kg of concentrate when fed at 6 kg/cow/d to cows grazing kikuyu-ryegrass pasture. A more practical recommendation might be to limit PKE to 200 g/kg of concentrate due to potential palatability problems and a slow rate of intake when fed during milking in the parlour. [ABSTRACT FROM AUTHOR]

Variations in the levels of the highly toxic oleandrin molecules were studied during composting of Nerium oleander L. waste mixed with clippings of the grass Pennisetum clandistenum L. The thermophilic phase is characterized by a rise in temperature, which reached 70°C. After 150 days of co-composting, the C/N ratio was 11, the pH was 8, the NO3−/NH4+ ratio was greater than 1 and overall decomposition reached 70%. During the successive stages of co-composting, oleandrin concentrations were monitored by HPLC. The relative abundance of oleadrin was 26.84% at T0 with 10% abatement during the first month and 90% after two months (stabilization phase), reaching 100%, i.e., total removal after 90 days of co-composting (maturation phase). The biodegradation of the toxic substance was largely attributed to the activity of actinomycetes and fungi. The germination index of lettuce and watercress seeds exceeded 50% after 90 days and reached 95% after 150 days, confirming that the final compost was mature, stable, and free from phytotoxicity in spite of the highly poisonous starting material. [ABSTRACT FROM AUTHOR]

Development of a soil quality index for kikuyu (Pennisetum clandestinum)-ryegrasss (Lolium spp.) pasture systems in the southern Cape of South Africa is important since there are certain warning signs that their sustainability is being threatened. A total of 142 pastures throughout the region were sampled and several soil physical, chemical and biological indicators were quantified. A minimum data set of the most sensitive indicators was chosen using principal component analyses. Linear scoring functions for these indicators were used to develop a soil quality index. The most sensitive indicators were: extractable P>gravel content>water holding capacity (WHC)>exchangeable acidity (EA)>soil organic matter (SOM)=penetration resistance (PR)>exchangeable Mn. The soil quality index (SQI) was equated as: SQI=0.13 (PR)+0.16 (Gravel)+0.15 (WHC)+0.14 (EA)+0.17 (P)+0.12 (Mn)+0.13 (SOM). This soil quality index is appropriate for pasture systems in the southern Cape of South Africa, and may be useful for similar pasture systems in other areas. [ABSTRACT FROM AUTHOR]

The ability to utilise leaf meal-based diets byOreochromis mossambicusof 12.5 g (SD 1) was evaluated. Nine diets of 30% crude protein and 20 MJ gross energy kg–1dry matter were formulated, comprising eight leaf-meal diets, where kikuyu leaf meal (KLM) and moringa leaf meal (MLM) each replaced 25%, 50%, 75% and 100% fishmeal, and a control diet containing no leaf meal. The experiment was conducted for 60 days in a recirculating system. All diets were randomly assigned to three groups of 15 fish. There was a significant decrease (p< 0.05) in growth with increasing levels of both leaf meals. Superior growth, higher protein digestibility and higher feed utilisation were recorded in fish fed KLM diets than those fed MLM diets. Fish fed MLM had higher numbers of goblet cells in the enterocytes, higher hepatocyte degradation and poorer haematological parameters than those fed KLM diets. Kikuyu grass has lower levels of anti-nutrients such as tannins, saponins and phytate than moringa leaves. The negative effects of anti-nutrients may be responsible for the poor performance of fish fed the moringa-based diets. Kikuyu leaf meal can replace up to 25% fishmeal inO. mossambicusdiets. [ABSTRACT FROM AUTHOR]

Kikuyu (Pennisetum clandestinum)–ryegrass (Loliumspp.) cultivated pastures form the base for dairy production in the southern Cape region of South Africa. The impact of various methods and implements used to over-sow ryegrass on the productivity and botanical composition of the pasture is unknown. The study aimed to assess the impact of cultivation along a soil disturbance gradient on the productivity and botanical composition of kikuyu-based pastures. Five tillage treatments were assessed, namely kikuyu over-sown with ryegrass using a minimum till planter, eradication of kikuyu with herbicide and ryegrass sown with a minimum-till planter, shallow (<150 mm) and deep (>150 mm) disturbance with a rotavator or conventional tillage, respectively, and a control. The autumn, spring, summer and annual productions of treatments with the least soil disturbance were the highest (P≤ 0.05). Shallow or deep tillage resulted in intermediate annual productions and the lowest (P≤ 0.05) was recorded for the herbicide treatment. Differences in production caused by different tillage methods were significant (P≤ 0.05) and changed the botanical composition. Kikuyu over-sown with ryegrass using a mulcher and minimum-till planter was the most viable option to manage cultivated pastures. [ABSTRACT FROM AUTHOR]

The efficacy of kikuyu grass and moringa leaves as protein sources in Tilapia rendalli (11.5 ± 1 g) diets was compared. Nine diets (30 % CP 20 MJ kg) were formulated by substituting fishmeal (FM) for kikuyu leaf meal (KLM) and moringa leaf meal (MLM). A control diet contained 10 % FM and no leaf meal. FM was replaced at 25, 50, 75 and 100 % by KLM in diets: KLM 25, KLM 50, KLM 75 and KLM 100, and then by MLM in diets: MLM 25, MLM 50, MLM 75 and MLM 100, respectively. Maize and gluten meals were adjusted accordingly. Each diet was fed to triplicate groups of fish for 60 days. The best growth (SGR and TGC) was in the control group. There was no significant ( P > 0.05) decrease in SGR and TGC when KLM replaced up to 50 % FM. There was a significant ( P < 0.05) decrease when MLM replaced >25 % FM. Kikuyu diets had no effect on villi height. A trend towards shorter villi was evident with increasing MLM. Hepatocyte degradation was higher in fish fed moringa-based diets. Anti-nutrients (tannins and polyphenols) in moringa may have contributed to the poor growth, irritation of the enterocytes and hepatotoxic effects. These results show that replacing up to 25 % FM with KLM is effective in reducing the costs without negatively impacting the growth performance or health of T. rendalli. Adding MLM even at the lowest level (25 %) was expensive and resulted in compromised growth and health. [ABSTRACT FROM AUTHOR]

The effect of a chemical compound fertilizer (N-P2O5-K2O, 20-5-5), applied in two forms (solid and liquid), on some indicators of the kikuyu grass (Pennisetum clandestinum) quality, was evaluated. The study was conducted at La Montaña farm, belonging to the University of Antioquia, Colombia. For that purpose, 28 plots were delimited and a randomized block statistical design was used, with the following treatments: T0 (without fertilization); T1, T2 and T3 (150, 200 and 250 kg ha-1 of solid fertilizer); T4, T5 and T6 (150, 200 and 250 kg ha-1 of liquid fertilizer). Three cuttings were performed, every 45 days, and samples were taken from each plot to analyze: green forage (GF), dry matter (DM), crude protein (CP), neutral detergent fiber (NDF), acid detergent fiber (ADF), crude energy (CE) and ash. With the application of the high fertilizer doses significant differences were found (p < 0,05) in the GF (9,5 t ha-1 cutting-1), CP (20,1 %) and DM production (1,9 t ha-1 cutting-1). The DM and NDF percentages were 23,4 and 65,6 %, respectively, in the control. The treatments did not have effect on the ADF, energy and ash contents. It is concluded that the compound fertilizer can be applied in solid as well as in liquid form; however, to use the dose of 200 kg ha-1 is recommended, because the nutritional value of the pasture is similar to the one obtained with 250 kg and the cost is lower. [ABSTRACT FROM AUTHOR]

The objective of this study was to evaluate the effect of the mixture of different ratios of kikuyu grass (Pennisetum clandestinum) (K) -- potato (Solanum tuberosum) (P) on methane production in vitro, during the second semester of 2012 in the University Research Center (Medellín, Colombia). The treatments consisted of mixtures K/P in ratios of 100/0 (T1), 75/25 (T2) and 50/50% (T3). The results were processed through a repeated measures analysis over time and nonlinear regression. At the end of incubation period (between 0 and 48 hours), the cumulative gas production (ml/g MSi), the cumulative methane production (ml/g MSi) and the dry matter digestibility were statistically differents (p<0.05) among all treatments, increasing with higher levels of potato in the mixture. In the same time interval, the relationship between dry matter digestibility and cumulative production of gas and methane (mg/ml) was statistically equivalent (p>0.05) among all treatments. The final volume of gas and methane (Vf) and its rate of production throughout the fermentation process (k), estimated from the Gompertz model, were also higher (p<0.05) for treatments including potato. Increased methane production is the result of higher dry matter digestibility according CNE level increases in the mixture. Under the in vitro model and in contrast to literature reports, the greater inclusion of CNE did not reduce methane production. [ABSTRACT FROM AUTHOR]

Pennisetum clandestinum (Graminae/Poaceae) an active Si-accumulator, was cultivated in two different substrata, both with reduced Si solubility. Plants growing in organic-rich soils contained much less Ca, K, Na and Si, than species growing in sandy soils. Although the highest macronutrient concentrations were associated to the highest Si levels in the organs of P. clandestinum, the R correlation values indicate that Si does not influence the internal balance and the uptake of these elements. In ca 65% of the cases roots have the highest average values regardless of the type of culture, while the contents of Mg in the shoots and roots of P. clandestinum were generally not significantly different (P>0.05). A significant decline of the macronutrient levels associated to the shoots and roots of P. clandestinum was observed from the 4th to the 6th month assay, especially for Ca in both organs, while for Mg and Na the decline is focused mainly in the shoots; K and Si decline is generally below 10%. When average values of Si in shoots and roots of plants collected from organicrich and sandy soils were plotted against the average concentrations of Ca, K, Mg and Na in the same organs, weak but positive R correlation values were obtained - the highest R values were observed for Na and K and the lowest for Ca and Mg, regardless of the culture. Exception for the high R value observed for K, although the influence of Si on the K status in the whole plant is time-depending - R values, diminished from the 4th to the 6th month, as it happens in the majority of the cases. In conclusion, P. clandestinum can grow well and healthily in substrata with acid pH values and high carbonate content and low solubility of Si suggesting that the definition of the essentiality of Si, even in a Si-accumulator plant is still a matter of great controversy. [ABSTRACT FROM AUTHOR]

Abstract: Global attention on biofuels and the potential for Jatropha curcas to produce biodiesel from marginal land with low inputs has recently created world-wide interest in this species. This paper reports on the water dynamics and productivity of J. curcas in a silvopastoral experiment with Pennisetum clandestinum at the Ukulinga research farm of the University of KwaZulu-Natal near Pietermaritzburg, South Africa. Measurements of daily total evaporation rates during December–February (summer) on clear hot days ranged between 3 and 4 mm d−1. However, due to the deciduous nature of the species, water use was negligible (<1 mm d−1) during winter (May–August). The results have shown that two- to four-year-old J. curcas trees were conservative water users. High oil yields are unlikely due to the low seed production. The best seed yield was in 2009 (348.8 kg ha−1) in the J. curcas only plots. The other treatments (where pasture competition was a factor) ranged between 77.8 and 166 kg ha−1. Data collected on the time taken by labourers to harvest and dehusk the seeds, showed that 1 kg of seed took approximately 3 h to process, suggesting that mechanical harvesting would be necessary to make seed production economically viable. J. curcas showed a low tolerance to pests and was prone to diseases. This significantly increased the input costs for insecticides and fungicides. The South African results are so unequivocal that J. curcas under the experimental conditions does not fulfil the claims that it is a wonder biodiesel plant. [Copyright &y& Elsevier]

Highlights: [•] Soil physical condition after conversion from virgin soil to pastures was examined. [•] Soil physical resistance increased after conversion. [•] Aggregate stability decreased after conversion. [•] Water holding capacity increased after conversion. [•] Dynamic soil physical quality was adversely affected, except for infiltration and water holding capacity. [Copyright &y& Elsevier]

Objective. To evaluate the effect of kikuyu offer and stage of lactation on fatty acids profile on milk fat of grazing dairy bovines. Materials and methods. Eighteen Holstein cows with average weight of 585±10 Kg in two to four calvings on first and second lactation stages. Cows were divided in three groups and assigned randomly to one of three treatments (pasture allowances of 2.6, 3.3 or 4.0 KgDM/100 Kg LW). Milk fatty acid profiles were determined on days 14 and 21 of the experimental period. Results. Fatty acids C6:0, C16:0, C18:lcis9, C18:3 remained constant between different forage allowances and lactation stage were used. On the treatments of highest allowance, there was an increase between days 14 and 21 of C10:0 andC12:0 acids while C18:ltll,C18:2c9cl2, C18:2c9,tll, and polyunsaturated fatty acids decreased their concentration. The lowest allowance had a different behavior. A higher concentration of ALC was observed in animals of second stage compared to ñrst stage of lactation. Conclusions. It was not possible to conclude on the effects of forage allowance on the fatty acid profile of milk, due to variations between sampling dates. It is possible that mobilization of fat storage can explain the different behavior of fatty acid concentrations between sampling days. [ABSTRACT FROM AUTHOR]

Abstract: High concentrations of sodium are toxic to most plant species, making soil salinity a major abiotic stress for plant productivity world-wide. Its salinity resistance makes the turf grass Pennisetum clandestinum Hochst (kikuyu grass) a candidate plant for utilization and reclamation of salinized areas. Kikuyu grass, a perennial native to the highlands of Central Africa now common in many areas, has recently become a valuable pasture and lawn plant because of its growth rate and well developed root system. However, its salt resistance has yet to be fully evaluated. The objective of this study was to identify the biochemical and physiological basis of salt resistance of kikuyu grass for the use of this grass as pasture, in phytoremediation, in controlling soil erosion and in biomass production for energy, in salt affected lands, where the growth of other species is markedly reduced. This study focused on the effect of salinity on germination, growth, metabolism, biochemistry, nutritive properties and root morphology of kikuyu grass. We compile evidence that kikuyu grass can germinate and grow in salinized areas. The use of this salt-tolerant grass may be an important part of a range of practices, such as recycling saline wastewater and reclaiming salt-affected soil in arid-zone irrigation districts. [Copyright &y& Elsevier]

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Background: This work focuses on the accumulation and mobility properties of arsenic (As) and the effects of phosphate (P) on its movement in Pennisetum clandestinum Hochst (kikuyu grass), grown hydroponically under increasing arsenate (As(V)) concentrations. The uptake of both ions and the relative kinetics show that phosphate is an efficient competitive inhibitor of As(V) uptake. The P/As uptake rate ratios in roots indicate that P is taken up preferentially by P/As transporters. An arsenite (As(III)) efflux from roots was also found, but this decreased when the arsenate concentration in the solution exceeded 5 μM. Methods: Increases in both arsenite and arsenate concentrations in roots were observed when the arsenate concentration in the solution was increased, and the highest accumulation of As(III) in roots was found when plants were grown at 5 μM As(V). The low ratios of As accumulated in shoots compared to roots suggest limited mobility of the metalloid within Kikuyu plants. Results: The results indicate that arsenic resistance in kikuyu grass in conditions of moderate exposure is mainly dependent on the following factors: 1) phosphate nutrition: P is an efficient competitive inhibitor of As(V) uptake because of the higher selectivity of membrane transporters with respect to phosphate rather than arsenate; and 2) a detoxification mechanism including a reduction in both arsenate and arsenite root efflux. Conclusions: The As tolerance strategy of Kikuyu limits arsenate uptake and As translocation from roots to shoots; therefore, this plant cannot be considered a viable candidate for use in the phytoextraction of arsenic from contaminated soils or water. [ABSTRACT FROM AUTHOR]

This paper has two objectives, the first is to determine the chemical composition, gas production parameters and the gas release kinetics, at different stages of maturity, of three grasses and a legume commonly found in long established pastures in Mexico central highland plateau. The second is to combine the gas release kinetics analysis and the GP fitted to a mathematical model in order to improve the biological understanding of the fermentation kinetics obtained from the GP technique. Representative samples of Pennisetum clandestinum (kikuyu grass), Sporobolus indicus (mouse tail), Eleocharis dombeyana (reed), Trifolium amabile (Aztec clover) plus a composite sample were collected in the growing season (July, September and November 2003) and analysed using an in vitro gas production (GP) technique. The accumulated GP was fitted to the model described in PALMER et al. (2005). Significant differences (P<0.001) were observed among species and periods for chemical composition, organic matter and neutral detergent fibre digestibility. Significant differences (P<0.05) were observed regarding fermentation parameters and gas release kinetic, with T. amabile and P. clandestinum being the species with the highest fermentability, whereas S. indicus and E. dombeyana were poorly fermented. P. clandestinum and T. amabile showed higher nutritive value than S. indicus and E. dombeyana. Composite samples were influenced by the chemical and fermentation characteristics of all species. It was concluded that the use of gas release kinetics analysis was useful for differentiating the fermentation kinetic of the soluble and insoluble fraction in the grasses and legume. Therefore by performing both approaches, the gas release kinetics analysis and the GP fitted to a mathematical model, gave a better description of the fermentation kinetic of grasses and the legume was achieved when only one approach had been used. [ABSTRACT FROM AUTHOR]

Abstract: A common lawn grass; kikuyu grass, an abundant vegetable; cabbage and vallisneria a common macrophyte were tested for utilisation by two size classes of a herbivorous fish, Tilapia rendalli held in glass aquarium tanks. The test feeds were given to sub-adult T. rendalli for 133days at 8% body weight and juvenile fish for 84days at 15% body weight. Sub-adult and juvenile fish fed kikuyu grass attained a higher specific growth rate, higher protein efficiency ratio and better food conversion ratio than those fed cabbage and vallisneria. This is explained by the differences in the protein content, higher levels of lysine and the sulphur-containing amino acid, methionine in kikuyu grass. Palatability studies of the juveniles also showed that kikuyu was most preferred. However, sub-adults preferred vallisneria, kikuyu and cabbage respectively. The possible reasons for the selection are discussed. [Copyright &y& Elsevier]