Mixed Crop-livestock Farming Systems Research Articles

Evaluation participative <em>ex ante</em> de propositions de la recherche. Cas d’application dans le sud du Togo

L’objectif de cette étude a été d’expérimenter une méthode d’évaluation participative d’options techniques au sud du Togo. Pour répondre aux besoins face aux problèmes de fertilité des sols dans un contexte de systèmes mixtes agriculture élevage, des chercheurs ont évalué avec les diverses catégories d’acteurs le potentiel d’adoption de l’association du maïs, plante à fonction mixte alimentaire (grain) et fourragère (paille), et du Mucuna pruriens, légumineuse à cycle long employée comme fourrage et pour améliorer la fertilité des sols. L’association fertilisée avec des engrais chimiques a été dénommée MME ci-après. La méthode utilisée a mobilisé des outils d’analyse de la méthode active de recherche participative (MARP) et a compris quatre phases. La première correspondait à la description générale de l’ensemble de la région d’étude pour identifier des sites représentatifs à partir de la littérature et d’entretiens exploratoires. La seconde phase a permis la caractérisation de la diversité des producteurs à partir d’entretiens auprès des personnes ressources des sites retenus. La troisième phase a concerné la sélection participative d’un éventail d’options techniques comprenant l’association MME mais aussi des pratiques locales présentant des similitudes avec l’association MME, ainsi que d’autres propositions alternatives de la recherche pour améliorer la fertilité des sols et assurer l’alimentation fourragère des animaux. Cette sélection a été réalisée par un échantillon de producteurs représentatifs de leur diversité. Il leur a été demandé de hiérarchiser les différentes options techniques présentées lors de visites de parcelles expérimentales ou à l’aide de supports visuels. Ils ont utilisé des notes ou des cailloux compte tenu de la forte proportion d’illettrisme. La quatrième phase a été celle de l’évaluation aux dires de producteurs des effets perçus des différentes options sur la gestion des ressources agropastorales (eau, sol, biodiversité), leur acceptabilité ou leur rentabilité en fonction du coût de la main d’oeuvre. Cette méthode a été appliquée dans trois villages du sud du Togo. Dans ces villages, six principales catégories de producteurs ont été identifiées : les propriétaires terriens, les locataires de terres, les membres d’organisations paysannes, les producteurs lettrés, les producteurs illettrés, et les femmes. En plus du MME, six options ont été retenues dont l’association MME avec des variantes issues de pratiques locales, soit l’association maïs et Mucuna à cycle long mais sans l’usage d’engrais (MM), l’association maïs et Mucuna à cycle court et à base d’engrais (MMCE), l’association maïs et Mucuna à cycle court sans l’usage d’engrais (MMC), et maïs en culture seul avec apport massif d’engrais (ME). Les deux autres options ont été proposées par la recherche : maïs entouré de haies vives de légumineuses fourragères destinées à du bétail en stabulation contrôlée et dont le fumier était ensuite épandu au champ (MHF), et culture en couloirs de maïs et de Cajanus cajan. L’association MME a été l’option préférée des propriétaires terriens, des lettrés et des membres d’organisations paysannes. Chez les femmes, l’option privilégiée a été l’association MM compte tenu de leurs faibles ressources financières mais aussi de leur insécurité foncière. Chez les locataires des terres et les producteurs illettrés, l’option favorite a été l’association MMCE qui permettait le maintien de la seconde saison de culture. L’évaluation des différentes options a montré que l’association MME et l’option MHF ont été jugées par la majorité des catégories de producteurs comme ayant les effets les plus positifs sur les ressources agropastorales. Les associations MME et MMCE ont été considérées comme étant les plus acceptables socialement, notamment chez les propriétaires terriens mais aussi chez les vulgarisateurs, les consommateurs et les commerçants également interrogés ; venait ensuite l’option MHF. La rentabilité a été la meilleure pour les associations MM et MME et la plus faible pour les deux autres alternatives proposées par la recherche. Cette méthode d’évaluation permet de valoriser l’expertise des producteurs. Elle repose sur la perception que les producteurs ont des effets des technologies. Une perception positive constitue un des premiers facteurs d’adoption d’une proposition de la recherche. Mais pour cela du temps et des outils appropriés doivent être consacrés à l’étape de formation des producteurs sur les différentes options pour que cette perception ne soit pas biaisée par la qualité de l’information donnée par le chercheur. Cette évaluation permet en outre d’identifier ou d’adapter des variantes locales aux options pré-identifiées par les chercheurs. Les efforts de recherche-développement doivent se concentrer sur les processus de ces adaptations participatives.

Near Infrared Reflectance Spectroscopy (NIRS) for determination of chemical entities of natural pasture from Ethiopia

In the mixed crop-livestock farming system of Ethiopia, natural pasture production is related to seasonal rainfall distribution which is restricted to only a few months of the year. Livestock owners in this country experience periods of excess forage in the rain season where preserving it through haymaking became tradition as a strategy for the periods of scarcity, particularly the dry season of a year. Forage can also be stored as standing hay, the cheapest way of conserving forage, in a place like pastoral and agro-pastoral production system where a decline in quality can be tolerated. Mixed grass-legume pasture samples from different agro-ecology were collected and portion of the samples were analyzed conventionally to determine their chemical composition (dry matter, ash, crude protein, neutral detergent fiber, acid detergent fiber, lignin) and in vitro dry matter digestibility to validate the NIRS calibration. NIRS was evaluated by the coefficient of determination in calibration (R 2 ), standard error of calibration (SEC), and standard error of cross validation (SECV). The results showed NIRS is extremely useful for predicting nutrient contents as compared to conventional chemical analysis methods which are not difficult to conduct, but they are expensive in terms of time and resources.

Factors influencing potential scale of adoption of a perennial pasture in a mixed crop-livestock farming system

Evaluating the potential scale of adoption of a technological innovation or management practice at the farm business scale can help gauge the potential size of an industry for the purposes of prioritising resources for research and development. In this paper we address the question of quantifying the potential area of adoption of a perennial pasture, lucerne ( Medicago sativa L.), in dryland mixed farming systems in Australia. Lucerne pastures play a significant role in dryland farming systems in the wheat-sheep zone of southern and western Australia. While there are benefits of integrating lucerne into cropping systems there will inevitably be additional costs, and the scale of adoption of lucerne will depend largely on the increase in farm profit resulting from the introduction of lucerne. Whole-farm economic models of representative farms in the Australian wheat-sheep belt were used to determine the key drivers for the scale of adoption of lucerne. For a particular farming system the optimal area of lucerne which maximises whole-farm profit is found to depend on production, price and cost conditions. Generally, no more than 30% of a farm was allocated to lucerne according to those conditions and location of the farm. For most scenarios examined the response of profit was flat around the optimal area. This implies that lucerne could be grown on areas greater than the optimum, in order to reduce groundwater recharge (and thereby reduce the risk of dryland salinity), without greatly reducing whole-farm profit. The optimal area of lucerne in all regions was limited by the area of suitable soil types and proportion of lucerne in the most profitable lucerne-crop sequences. At all price levels assumed in this study lucerne remained as part of the optimal enterprise mix for all farm types examined. Lucerne productivity was also a major determinant of the optimal area of lucerne. The sensitivity of profit to changes in winter and/or summer production varied between regions and for different livestock enterprises. The differences were driven by the timing of energy demands and supply of feed in individual farming systems. In all regions the optimal area and profitability of lucerne varied with livestock enterprise. The analyses showed that changing from wool production to meat production enabled greater economic benefit to be realised from lucerne. This was consistent across farm types and demonstrated the value of lucerne as a source of high quality feed for finishing prime lambs in summer. The results of this study demonstrate that lucerne is profitable in a range of environments on a significant proportion of the farm area, but that this area is small relative to that required to significantly influence in its own right the environmental issue of salinity.

Evaluation of lablab and velvet bean fallows in a maize production system for improved livestock feed supply in semiarid tropical Kenya

The mixed crop–livestock farming systems of semiarid tropical Kenya are characterised by low livestock feed supply. The contribution of lablab and velvet bean to fodder production in a maize production system was investigated in the eastern region of Kenya. The experiment was run in three cycles, where each cycle consisted of a short legume fallow phase of ~6 months, followed by a maize-cropping phase. At the end of the fallow phase, the legume herbage was incorporated in soil at three levels; 0, 50 and 100% of total DM yield and maize planted. Maize yield from the legume fallow plots was compared with maize grown after natural fallow and maize top-dressed with 40 kg nitrogen/ha and nil nitrogen fertiliser. Overall, herbage DM yield was highest in velvet bean (3.9 t/ha) followed by lablab (3.4 t/ha) and lowest in natural fallow (2.2 t/ha). Mean crude protein from velvet bean was 13.5% of DM, which was significantly (P < 0.05) higher than that of lablab (8.4% of DM) and natural weedy fallow (3.5% of DM). Maize grain yield following lablab fallow was 38% (3569 kg/ha) and 27% (1810 kg/ha) in short rains (SR) 2002 and SR 2004, respectively, higher than maize succeeding natural fallow. However, maize planted after velvet bean fallow was 43% (3728 kg/ha) and 29.4% (1828 kg/ha) in SR 2002 and SR 2004, respectively, higher than in maize grown after natural fallow. Generally, the highest maize yield among the fallows was recorded in plots where legumes were incorporated in soil at 50% of total DM implying that the other 50% was available for livestock feed. Maize stovers DM yields were highest at the higher (100%) and middle (50%) level of legume incorporation, and yields were more than those from natural weedy fallow. Maize production under the legume fallow system was more profitable than from natural weedy fallows. It was concluded that if lablab and velvet bean are integrated in cropping systems as fallows, they can provide highly nutritious livestock feeds and improve maize yield and are recommended in the maize production systems within semiarid tropical Kenya.

Improving water productivity in mixed crop–livestock farming systems of sub-Saharan Africa

In sub-Saharan Africa problems associated with water scarcity are aggravated by increasing demands for food and water, climate change and environmental degradation. Livestock keeping, an important livelihood strategy for smallholder farmers in Africa, is a major consumer of water, and its water consumption is increasing with increasing demands for livestock products. At the same time, current low returns from livestock keeping limit its contribution to livelihoods, threaten environmental health and aggravate local conflicts. The objectives of this review are to: (1) synthesize available knowledge in the various components of the livestock and water sectors in sub-Saharan Africa, (2) analyze livestock–water interactions and (3) identify promising strategies and technological interventions for improved livestock water productivity (LWP) using a framework for mixed crop–livestock systems. The interventions are grouped in three categories related to feed, water, and animal management. Feed related strategies for improving LWP include choosing feed types carefully, improving feed quality, increasing feed water productivity, and implementing grazing management practices. Water management for higher LWP comprises water conservation, watering point management, and integration of livestock production in irrigation schemes. Animal management strategies include improving animal health and careful animal husbandry. Evidence indicates that successful uptake of interventions can be achieved if institutions, policies, and gender are considered. Critical research and development gaps are identified in terms of methodologies for quantifying water productivity at different scales and improving integration between agricultural sectors.

Livestock water productivity in mixed crop–livestock farming systems of the Blue Nile basin: Assessing variability and prospects for improvement

Water scarcity is a major factor limiting food production. Improving Livestock Water Productivity (LWP) is one of the approaches to address those problems. LWP is defined as the ratio of livestock’s beneficial outputs and services to water depleted in their production. Increasing LWP can help achieve more production per unit of water depleted. In this study we assess the spatial variability of LWP in three farming systems (rice-based, millet-based and barley-based) of the Gumera watershed in the highlands of the Blue Nile basin, Ethiopia. We collected data on land use, livestock management and climatic variables using focused group discussions, field observation and secondary data. We estimated the water depleted by evapotranspiration (ET) and beneficial animal products and services and then calculated LWP. Our results suggest that LWP is comparable with crop water productivity at watershed scales. Variability of LWP across farming systems of the Gumera watershed was apparent and this can be explained by farmers’ livelihood strategies and prevailing biophysical conditions. In view of the results there are opportunities to improve LWP: improved feed sourcing, enhancing livestock productivity and multiple livestock use strategies can help make animal production more water productive. Attempts to improve agricultural water productivity, at system scale, must recognize differences among systems and optimize resources use by system components.

Agro-Ecological Indicators (AEIs) for Dairy and Mixed Farming Systems Classification: Identifying Alternatives for the Cuban Livestock Sector

Attainment of acceptable levels of land and labor productivity and low external input use is not a mutually exclusive proposition. This study examines characteristics of a range of current specialized dairy farming systems (DFS) and mixed (crop-livestock) farming systems (MFS) in Cuba to determine their efficiency in the process of food and feed production. The central question was whether the favorable results of MFS realized in a small-scale experimental system were also attainable in larger, commercial farms. To this end, we collected data on 93 farms from around the country for a period of 1 year. The farms were classified according to four predictor variables: farm type, years since conversion from DFS to MFS, proportion of land allocated to crops in rotation and farm size. Farms were compared based on 12 pre-selected Agro-Ecological Indicators (AEIs) by using analysis of variance and Tukey's HSD tests. The 12 AEIs were also subjected to a principal components analysis and related to the four predictor variables by reduced-rank regression, also known as redundancy analysis. Three farm types were distinguished: mixed farming experimental (MFe), mixed farming commercial (MFc) and specialized dairy farming (DFS). Total energy output per unit of farm area was on average four to six times higher on the mixed farms than on the specialized dairy farms, while protein output three to four times higher. Milk yield per unit of forage area was highest on MFe (2.4 Mg ha−1 yr−1), followed by MFc (1.7), while it was much lower (0.7) on DFS. The redundancy analysis revealed that MFe did only slightly better than MFc and was most opposite to DFS in terms of AEIs. In conclusion, the previous experimental findings were confirmed nationwide, thus demonstrating the benefits of MFS for agro-ecological performance in Cuba.

Crop–Livestock Interactions in the West African Drylands

Many semiarid regions of Sub‐Saharan Africa (SSA) are experiencing vast increases in human population pressure and urbanization. These augment the demand for agricultural products and have led to the expansion, intensification, and often closer integration of crop and livestock production systems. The transition of crop and livestock production from the current relatively extensive, low input/output modes of production to more intensive, higher input/output modes of production presents numerous challenges to the achievement of required long‐term production increases from these farming systems. This paper provides an overview of the challenges facing agricultural production in semiarid SSA with a focus on West Africa. A description of mixed crop–livestock farming systems and their evolution is followed by an overview of the principal linkages between crops and livestock: income, animal power, feed, and manure. The most detailed discussions relate to nutrient cycling in these farming systems. Most livestock derive their feed almost exclusively from natural rangeland and crop residues, and livestock manure is a precious soil fertility amendment. However, most farmers have insufficient livestock and therefore manure to sustain food production. Nutrient harvests from cropland often exceed nutrient inputs, and soil nutrient depletion is a principal concern. The paper concludes with a discussion of strategies that may improve the productive capacity of these mixed farming systems.

Crop–Livestock Interactions in the West African Drylands

Many semiarid regions of Sub-Saharan Africa (SSA) are experiencing vast increases in human population pressure and urbanization. These augment the demand for agricultural products and have led to the expansion, intensification, and often closer integration of crop and livestock production systems. The transition of crop and livestock production from the current relatively extensive, low input/output modes of production to more intensive, higher input/output modes of production presents numerous challenges to the achievement of required long-term production increases from these farming systems. This paper provides an overview of the challenges facing agricultural production in semiarid SSA with a focus on West Africa. A description of mixed crop–livestock farming systems and their evolution is followed by an overview of the principal linkages between crops and livestock: income, animal power, feed, and manure. The most detailed discussions relate to nutrient cycling in these farming systems. Most livestock derive their feed almost exclusively from natural rangeland and crop residues, and livestock manure is a precious soil fertility amendment. However, most farmers have insufficient livestock and therefore manure to sustain food production. Nutrient harvests from cropland often exceed nutrient inputs, and soil nutrient depletion is a principal concern. The paper concludes with a discussion of strategies that may improve the productive capacity of these mixed farming systems.

Policies for livestock development in the Ethiopian highlands.

Since 1991, there have been significant changes in utilization of feed resources in the Ethiopian highlands: while use of communal grazing lands and private pastures has declined, use of crop residues and purchased feed has increased. In addition, although use of animal health services and adoption of improved livestock breeds and modern management practices have increased, ownership of various types of livestock has declined. Rapid population growth has contributed most to the declining trends in grazing resources and ownership of livestock, showing the negative effects of increasing pressure on already degraded resources in the Ethiopian highlands. Land redistribution, increased participation in credit and extension programs targeting livestock, and improvement in access to markets, on the other hand, have had significant positive impacts on adoption of improved livestock technologies and ownership of livestock. Thus, reducing population growth and improving access to markets and credit and extension programs targeting livestock can enhance the role of livestock in improving food security and reducing poverty, especially in the mixed crop-livestock farming systems as exist in the East African highlands.

Habitat management strategies for the control of cereal stemborers and striga in maize in Kenya

Maize is the principal food and cash crop for millions of people in the predominantly mixed crop-livestock farming systems in Kenya. Stemborers and striga (Striga hermonthica) are major constraints to increased maize production in eastern Africa. An intercropping and trap crop system has been developed, using a ’push-pull’ strategy, for the control of stemborers in small scale maize farming systems. The ’push-pull’ strategy involves trapping stemborers on highly susceptible trap plants (pull) and driving them away from the crop using repellent intercrops (push). Napier grass (Pennisetum purpureum Schumach) and Sudan grass (Sorghum vulgare sudanense Stapf.) are used as trap plants, whereas molasses grass (Melinis minutiflora Beauv.) and two species of desmodium (Desmodium uncinatum Jacq. and Desmodium intortum Urb.) repel ovipositing stemborers. The integrated ’push-pull’ strategies were shown to increase parasitism of stemborers through attraction of parasitoids to one of the intercrops, molasses grass. The leguminous intercrop, silver leaf desmodium, drastically reduced damage to maize by the parasitic weed, striga. This aspect was further investigated and developed for integration **********w;th stemborer control. On-farm trials with farmers in Kenya have shown significant yield increases in maize farming.

Implications of livestock feeding management on soil fertility in the smallholder farming systems of sub-Saharan Africa

The role of livestock in nitrogen cycling in mixed crop–livestock farming systems of sub-Saharan Africa was explored. Cattle were fed a range of diets to investigate the effects on partitioning of nitrogen between urine and faeces and on the chemical composition of the manures produced. The trade-offs in efficiency between using the feed resources as a direct soil amendment for crop production compared with feeding to livestock and use of the manure as a fertiliser are discussed. Increased dry matter (DM) and nitrogen intake of a poor quality basal diet (barley straw) was achieved by supplementation with 15 and 30% of DM offered as Calliandra calothyrsus, Macrotyloma axillare or poultry manure. Urinary-N excretion for the basal diet (0.5 mg kg −1 liveweight (W) per day) was similar to C. calothyrsus at 15 and 30% supplementation (1.3 and 0.8 mg kg −1 W per day, respectively) and M. axillare at 15 and 30% supplementation (0.4 and 0.6 mg kg −1 W per day, respectively). In contrast, feeding poultry manure, a supplement containing highly degradable N, resulted in larger excretions of excess rumen ammonia as N in the urine, 17.5 and 23.2 mg kg −1 W per day for 15 and 30% supplementation, respectively. Diets containing the largest rate of C. calothyrsus supplementation had the lowest digestibility of N in the acid detergent fibre (ADF) and neutral detergent fibre (NDF) fractions. This was reflected in faeces from cattle fed diets supplemented with C. calothyrsus, which had substantially greater amounts of N bound to fibre (ADF and NDF) fractions than faeces from the other diets. When incubated in leaching tubes prunings of C. calothyrsus showed net N mineralisation from week 2, whereas barley straw, M. axillare and poultry manure immobilised N for >28, 24 and >28 weeks, respectively. Faeces derived from supplementation with C. calothyrsus and M. axillare resulted in shorter nitrogen immobilisation in leaching tubes (16 weeks) than supplementation with poultry manure (24 weeks) when compared with faeces derived from animals fed straw only (28 weeks). Similarly, reduced N uptake from 10-week-old maize plants was observed in pots to which faeces had been added compared with the control treatment. A second crop of maize had increased N uptake. Feeding poor quality crop residues like barley straw to animals produces manures with a decreased capacity to immobilise mineral N in the soil. This was shown with faeces derived from feeding ruminants a diet of only barley straw, which had a faster N mineralisation rate than fresh barley straw, a shorter and smaller N immobilisation stage in leaching tubes and gave greater N uptake in maize grown in pots. These results indicate that N losses in urine from livestock may be less important than previously thought. Most of the N is excreted in the faeces, which must be conserved and managed to maximise nutrient cycling.

Alternatives to Crop Residues for Sustaining Agricultural Productivity and Natural Resource Conservation

ABSTRACT When left in fields after grain harvest, crop residues enhance nutrient cycling, soil and water conservation, and subsequent crop yield. However, many agricultural systems rely on crop residues for other uses, such as livestock feed, fuel, and construction material. This paper examines the key functions of crop residues in mixed crop-livestock farming systems and suggests alternatives to crop residues for sustaining agricultural productivity and natural resources. Various soil management and related practices allow crop residues to be removed without adversely affecting the soil environment. These include the introduction of alternative crop genotypes that produce both sufficient grain and residues of good quality; the partial rather than total removal of crop residues through selective crop residue harvest/return practices; provision and strategic use of chemical fertilizer and animal manure; substituting forages for crop residues; use of clean or reduced tillage; use of structural and support practices that complement tillage; and application of surface soil-amending materials. Not all practices are adaptable to all conditions, but one or more practices should be suitable for sustaining land productivity under most conditions where crop residues are limited or used for other purposes.