Journal of Agriculture and Rural Development in the Tropics and Subtropics (JARTS)
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Determinants of households’ membership in agricultural cooperatives in Bhutan
Get PDFThe Royal Government of Bhutan has been promoting agricultural cooperatives (ACs) in the country; however, the number of people joining ACs is small. This study was conducted to identify the factors influencing households' decision to join ACs in Central Bhutan. A cross-sectional survey was conducted to collect data from 384 households (192 AC members and 192 non-AC members). Trained enumerators collected data in June and July 2018 using structured questionnaires. The binary logistic regression showed that households with older heads of household, being literate, having more family labour, more land under cultivation, owning farm machinery, being further away from a market, and having access to credit increased the likelihood of households joining ACs. Conversely, households earning off-farm income and locating far from the Renewable Natural Resources Centres decreased the likelihood of becoming member of ACs. Additionally, the gender of the head of a household and the number of cattle owned by a household showed no significant influence. As this paper is the first to empirically investigate the determinants of households’ membership in ACs in Bhutan, the findings have some important policy implications. The government should continue to provide in-depth awareness to farmers on concepts and benefits of ACs in retaining existing members and recruiting new members
Application of non-linear models in description of growth of dual purpose FUNAAB Alpha chickens
Get PDFGrowth is explained mathematically by models that have parameters with biological interpretations. This study was conducted to compare five non-linear growth models (Gompertz, Brody, Logistics, Von Bertalanffy and Negative exponential) in order to describe growth in the three genotypes (normal feather, naked neck and frizzle feather) of the dual purpose FUNAAB Alpha chickens (n=332). Doesn’t Use Derivative iterative method of nonlinear procedure in SAS was used to estimate the model parameters. Computational difficultly, goodness of fit and residuals of the five models were also evaluated. Negative exponential model predicted the highest mature weight for the three genotypes while Logistics model predicted the highest coefficient of intensity of growth. The fitting of the five models presented no computational difficulty for normal feather chickens while Logistics failed to converge for male, naked neck and frizzle feather chickens. Based on goodness of fit (coefficient of determination, Bayesian information criterion, mean square error and residuals), Gompertz model was observed to have the best fit for normal feather and naked neck chickens while Brody model have the best fit for frizzle feather chickens and Von Bertalanffy for male chickens. From subjective approach (comparison of observed and predicted body weights), Logistics and Negative exponential models fitted well for normal feather than other models while Negative exponential model was the fittest among the models for naked neck and frizzle feather chickens and Gompertz for female chickens. It can be concluded that choice of appropriate model in description of growth depends on genotype and sex of dual purpose FUNAAB Alpha chickens
Effect of different mechanical seed scarification methods on germination and emergence dynamics of baobab (Adansonia digitata L.)
Get PDFThe African baobab (Adansonia digitata L.) is a multipurpose fruit-producing tree that is indigenous to the African savannahs. Commercial interest in the species has grown in recent years. The major obstacle of seed-based propagation of baobab is its inherent seed dormancy. Therefore, in this study the effects of different mechanical seed scarification methods on seed germination parameters and seedling development of A. digitata were tested. The results show that mechanical scarification had a significant effect on germination and emergence dynamics of A. digitata. The highest total emergence percentage with 61.7% was achieved by scarifying the seeds with a saw on the hilum side. Cotyledon damage due to mechanical scarification occurred in all treatments. Proportions of damage categories depended significantly on treatment. The largest proportion of undamaged cotyledons was with 63.6% achieved by scarifying the seeds with a saw on the hilum side. This precise technique may be suitable for mass propagation of baobab in a rural setting but the effects of scarification methods on seedling emergence should be further investigated
Early planting and relay cropping: pathways to cope with heat and drought?
Get PDFMaize (Zea mays) is an important food and cash crop of uplands in Southeast Asia, where it is often prone to drought and heat stress associated with climate change. This study aimed at assessing the effect of heat and drought on maize performance, testing coping strategies under such weather extremes, and understanding associated mechanisms. The experiment was carried out during 2018 in Thailand, using a split-plot design with three replications. Treatments were: July-planted maize sole cropping (control), July-planted maize-mungbean (Vigna radiata) relay cropping, and June-planted maize sole cropping. High temperatures and dry spells during July-August 2018 decreased maize growth strongest in the control and less so in maize relay cropping during generative growth stages, but not in June-planted maize sole cropping. Stress reduced maize nitrogen nutrition index by 40%. Relay-cropped maize had a significantly higher potential to keep stomata open (320 mmol m-2 s-1) than sole-cropped maize (100 mmol m-2 s-1). Δ13C of maize grains confirmed that June-planted maize (‑9.43‰) was less affected by dry spells and heat stress than July-planted sole cropped maize (‑10.23‰). Under relay cropping, the latter showed less water stress (δ13C: ‑10.12‰) compared to sole cropping and a higher soil water use. Maize was better able to cope with heat and drought stress when relayed-cropped, although less compared to early-planting of maize. Hence, the tested coping strategies are able to mitigate heat and drought effects on maize growth, while improving food security and crop diversification when relay-cropped with mungbeans
Tillage system and integrated soil fertility inputs improve smallholder farmers’ soil fertility and maize productivity in the Central Highlands of Kenya
Get PDFWe designed and implemented an on-farm trial in Meru South and Gatanga sub-counties to understand the effects of integrated soil fertility management (ISFM) technologies on soil nitrogen (N), phosphorus (P), potassium (K), and maize productivity. The technologies included combinations of mineral fertiliser and maize stover (CrMf); crop residue, Tithonia diversifolia and rock phosphate (CrTiP); crop residue, Tithonia diversifolia and goat manure (CrTiMan); crop residue, inorganic fertiliser and goat manure (CrMfMan); crop residue, goat manure and Dolichos lablab (CrManLeg), and sole inorganic fertiliser (Mf) executed under conventional (ConC) and minimum (MinTill) tillage methods. We interviewed the farmers who participated in implementing the trials at the end of the study to understand the likelihood to uptake the technologies. We observed that the technologies increased soil N, P, K, and maize productivity compared to ConC (the control). There was a high likelihood of uptake of high-performing ISFM technologies. We recommend CrTiP for the two sub-counties for the short-term. However, a long-term experiment is needed to evaluate performances of CrTiMan, CrTiP, CrMfMan, and CrManLeg under the two tillage methods for site-specific recommendations taking into consideration rainfall variations
Rainfall erosivity, soil erodibility and natural water erosion potential in the Huambo region, Angola
Get PDFThe use of erosion assessment methods is critical for the sustainability of land use in tropical and subtropical regions, especially in countries lacking national information on soil erosion development, which is the case of Angola. This study aimed to evaluate the rainfall erosivity (R), soil erodibility (K), soil loss tolerance (T) and natural erosion potential (NEP) in Huambo (Angola). The R value estimated for a 25-year period was 7463 MJ·mm·ha-1·h-1·y-1. K values estimated from 25 soil profiles, described in the Soil Map of Angola, varied from 0.021 to 0.247 t·ha·h·ha-1·MJ-1·mm-1, respectively, in yellow ferralitic and paraferralitic soils (Ferralsols) and brown psamitic soils (Arenosols). A two-principal component (PC) model for soil erodibility variables explained 61.7% of total variance. PC1 was related to particle size distribution and soil erodibility, pointing to a positive correlation between sand content in the soil superficial horizons and K. PC2 expressed soil loss vulnerability, with negative factor loading for soil loss tolerance. The cluster analysis (CA) grouped Arenosols in a significant cluster located in the positive quadrant of PC1, therefore, more erosion prone. The NEP average value found was of 605 t·ha-1·y-1. The obtained results raise awareness concerning soil degradation by water erosion and can be of value for decision-makers and for farmers and land users, contributing to the sustainability of agriculture in Huambo
Litter characteristics of pine shavings, bio-secure pine shavings and sunflower hulls and its impact on broiler performance
Get PDFThe aim of this study was to investigate the physical characteristics of three litter materials, namely pine shavings (PS), bio-secure, fumigated pine shavings (BS) and sunflower hulls (SH) and its influence on broiler performance over a 33-day production cycle. The experiment was conducted in commercial poultry houses holding 42,500 chicks each, utilising a randomised block design with six house replicates per treatment. Litter samples were collected weekly for analyses of moisture, water-holding capacity, bulk density, pH and litter caking. Broiler footpad dermatitis was monitored at 21 and 31 days, together with acid detergent fibre (ADF) concentration of gizzard content, gizzard weight and small intestinal weight and length of 120 birds per treatment. Broilers across treatments consumed litter material which was evident in increased ADF levels of gizzard contents relative to feed. The SH contained more nutrients based on proximate analysis as compared to other treatments. Rearing on SH led to lower 7-day cumulative mortality, higher kilograms of broilers produced per square meter, average daily gain and slaughter weight. Improvements seen with SH did not alter commercial indicators, namely, production efficiency factor and feed conversion ratio. Litter converged toward similar physical characteristics at the end of production cycles when few differences were observed between treatments due to addition of feed, feathers and excreta
Incorporation of dried goat rumen contents in layer diets improves egg yolk colour and acceptability of eggs
Get PDFThe use of dried goat rumen content (DGRC) as a partial replacement for fish meal in layer diets was investigated. A total of 90 HN Brown Nick layer chickens were offered diets in which DGRC were incorporated at 0, 5 and 10% levels. Iso-caloric and nitrogenous diets were formulated to meet the recommended nutritional requirements for laying hens. Experimental birds were assigned to 9 cages (10 birds/cage) and experimental diets offered in a completely randomized design (CRD) with three replications. Data was collected on egg production and sensory characteristics of the eggs, and a partial budget analysis was undertaken. Diet significantly (P0.05) affected average daily feed intake (ADFI) and feed conversion ratio (FCR). There was an increase in ADFI and FCR with increasing levels of DGRC in the diets. The results showed that, though there was a gradual decrease in laying percentage with increase of DGRC in the diets, laying percentage did not differ in layers fed on 0 and 5% DGRC diets (P0.05). Eggs from layers offered 10% DGRC were more acceptable than those of layers fed on 0 and 5% diets. A significant effect (P0.05) of treatments on yolk colour was observed. Eggs from 10% DGRC diets had more deep yellow yolks than eggs from 0 and 5% diets. It was concluded that use of DGRC in layer diets improved yolk colour, acceptability of the eggs and marginal rate of return (MRR)
Analysis of the nutritional and productive behaviour of dairy cows under three rotation bands of pastures, Pichincha, Ecuador
Get PDFThis research was carried out on Pennisetum clandestinum-based pastures to identify the effect of three (3) types of stocking methods with similar forage allowance (8.2 kg of dry matter for 100 kg of live weight) but differing by the occupation times of the rotations (3 h, 24 h, and continuous) on the behaviour and the production of dairy cows. The experimental scheme consisted in three herds of four Holstein Friesian cows grazing three paddocks, one per rotationtype, for one week and replicated three times in a cross-over design. Pasture height and biomass were measured before and after each grazing week and on a daily basis, two cows per herd were monitored during daytime with activity sensors and their milk production was recorded. The main results showed that in all treatments the cows reduced the height of the sward by 40% on average. The cows in the continuous treatment spent more time in meals and tended to have higher average speed during the day than in the 3-h rotation ascribed to a higher exploration of the whole gradable area every day in the continuous treatment and to more time idling animals in the 3-h treatment in anticipation of the opening of new areas to graze over the course of day. Despite those difference in activity, milk production did not differ neither in quantity with an average of 12.4 0.14 kg per day, nor in quality (i.e., fat, protein, non-fatty solids, total solids). We conclude that under our grazing conditions with an intermediate forage allowance and low producing cows, applying a labour intensive stocking method requiring to open new areas every 3 hours does not lead to a significant production increase
Nutrient digestibility, nitrogen balance and rumen fermentation parameters of West African dwarf goats offered treated maize stover supplemented with Gmelina arborea
Get PDFA large portion of agricultural crop residues are potential feed resources for ruminants in the tropics. This study therefore, investigated the intake, nutrient digestibility, nitrogen utilisation and rumen fermentation parameters of West African dwarf goats (WAD) fed treated and untreated maize stover supplemented with Gmelina arborea. Twenty male WAD goats (11.50 ± 0.45 kg body weight) were randomly allotted into four treatments with five animals each. Untreated maize stover (MS), urea treated maize stover (UT), molasses treated maize stover (MT) and urea-molasses treated maize stover (UMT) were supplemented with 300 g Gmelina arborea (G) and were offered to each group for three weeks. MS had highest dry matter (DM; 87.1%), neutral detergent fibre (76%), acid detergent fibre (45%) and acid detergent lignin (6%) contents (P0.05). Crude protein content was high in UT (12.5%) and UMT (13%). Animals fed UMT+G recorded higher DM intake and digestibility, whereas crude protein digestibility was higher in animals on UT+G (72.8%) and UMT+G (76.2%). Nitrogen intake was more in goats fed UMT+G (P0.05) and least in MS+G fed group. Higher nitrogen was absorbed and retained by goats on UMT+G. The pH of the ruminal fluid was not affected by the dietary treatments. Concentrations of ammonia‑nitrogen and total volatile fatty acids were higher in UMT+G fed animals. Thus, UMT+G is a good option for proper nutritional utilisation of maize stover which can easily be adopted by farmers given the availability of materials (Gmelina arborea, maize stover, urea and molasses) and simplicity of the technology involved in the treatment of the stover