A comparison of in-field techniques for estimating the feed intake of young boer goats on a Leucaena leucocephala/grass hay diet.

Thesis (M.Sc.)-University of Natal, Pietermaritzburg, 1997.Two methods of estimating the intake of a 25% leucaena : 75% grass hay diet by young male Boer goats were assessed, (a) The purine derivative technique which uses the urinary excretion of purine derivatives (expressed relative to creatinine concentration in the same sample) as an index of feed intake, and (b) the conventional marker method, utilizing chromic oxide (Cr₂O₃) contained in gelatin capsules and dosed twice daily, as the marker. Following a prerun the two techniques were compared in three runs of an indoor experiment. In each run 10 goats were randomly allocated to five feeding levels (500 to 1100 g fodder d ¯¹ on air dried basis). A preliminary and an adaptation period during which goats were dosed with the Cr₂O₃ and fed their daily feed allowance, was followed by a 4 day collection period during which spot samples of urine were collected and analysed for allantoin and creatinine (allantoin being used instead of total PDs) and faecal samples were collected for chromium analysis and percentage dry matter determination. For the first two runs, two grab samples per day for each goat were bulked and analysed for chromium content. For the last run, the total daily faecal collection was subsampled and analysed for chromium. Work was done in metabolic crates to determine the effect of time of collection on the ratio of allantoin : creatinine (A/C) in spot urine samples and it was found to non-significant (P>0.05). Linear regressions of: (a) feed intake expressed per unit metabolic mass (g.d ¯¹.LW ¯°∙⁷⁵ (I_mmass)) against A/C ratio; (b) faecal output (g d ¯¹) against feed intake (g d ¯¹); and (c) faecal chromium concentration (mg kg ¯¹) against faecal output (g d ¯¹) were fitted to the data. During the prerun, only regression (a) was fitted and was non-significant (P>0.05), showing no trend at all. For the first true run, the regression of I_mmass against A/C ratio was significant and the correlation was high (P≤ 0.001, R² [A] 0.715, n = 10) but for the second and third runs, the correlations only became significant when the apparent outliers were discarded from the data. (Run 2: P≤ 0.001, R² [A] 0.824, n = 8; Run 3: P≤ 0.05, R² [A] 0.430, n = 9). It was concluded that the relation between I_mmass and A/C ratio is not well enough defined to be used for predictive purposes. When regression (b) was investigated, all the runs produced significant results (P≤0.001, P≤0.01, P≤ 0.001 for runs 1,2 and 3 respectively) however the correlations were not as high as expected (R² [A] being 0.714, 0.565 and 0.863 respectively). For the regression of faecal Cr concentration against faecal output (regression c), all runs showed significant relations (P< 0.001, P< 0.0001, P:s 0.001 for runs 1,2 and 3 respectively) and the correlations were high (R²[A] being 0.836, 0.837 and 0.912 respectively). The data from the three runs were pooled and single equations established for regressions (b) and (c) to allow for the prediction of intake from faecal chromium concentration. Faecal output = feed intake * 0.448 + 19.341 (P≤ 0.001, r 0.853, R² [A] 0.718, SE 25.664, n - 30) Faecal chromium concentration = faecal output * -241.547 + 1.315E+05 (Ps 0.001, r 0.904, R² [A] 0.811, SE 5603.788, n = 30). In vitro figures were determined for a range of leucaena : hay mixes but no apparent trend was found between percentage leucaena in the mix and the digestibility of the mix. These results compared favourably with in vivo results obtained for a 25% leucaena : 75% hay mix. Neither technique proved entirely satisfactory, but the external marker method was found to be more effective than the purine derivative technique. More work is required especially with respect to the latter method

Mieux évaluer et accompagner l'innovation agricole en Afrique. Leçons d'une analyse transversale de 13 cas d'études

Cet article présente les résultats clés tirés de l'analyse transversale de 13 expériences d'innovation agricole menées au Bénin, au Kenya et en Afrique du Sud. L'évaluation a utilisé un cadre analytique commun inspiré de l'approche systèmes d'innovation pour comprendre comment l'innovation a évolué au fil du temps via les interactions entre différents acteurs et sous l'effet d'éléments déclencheurs et moteurs internes et externes. Menée de manière participative par des équipes mixtes de chercheurs, d'étudiants et d'acteurs locaux, elle s'est fondée sur des entretiens semi-structurés, des focus groupes et des ateliers multi-acteurs. Les 13 cas portent sur une diversité d'expériences en termes de domaines, types, échelles, durée, initiateurs de l'innovation et acteurs concernés. Les résultats montrent la multiplicité et le rôle des acteurs impliqués dans l'innovation, la nature des déclencheurs et moteurs de l'innovation. Ils montrent aussi l'importance de la prise en compte du temps long pour comprendre les processus d'innovation. Ils montrent enfin l'influence tant positive que parfois problématique des interventions externes sur les processus d'innovation, et en particulier les difficultés à institutionnaliser l'innovation au-delà des interventions ou à interagir avec les dynamiques locales d'innovation. L'article propose diverses voies pour améliorer tant l'évaluation que l'accompagnement des processus d'innovation. Cela concerne en particulier la conception et le financement des interventions externes. Cela concerne aussi l'acquisition des compétences et capacités indispensables à la mise en oeuvre dans la durée d'approches ouvertes et souples de conception, renforçant chaque fois que possible les initiatives existantes des acteurs locaux. (Résumé d'auteur

A critical comparative review of evidence on alternative instruments for supporting research and innovation in agri-food systems in the Global South

Financial support is a critical enabling factor for healthy agri-food innovation systems, particularly within resource-limited settings, though additional forms of support are also necessary. This motivated a critical comparative review of evidence in peer-reviewed and gray literature on the range of instruments that support innovation in agri-food systems in the Global South, toward achieving sustainable agriculture intensification. The main aim is to provide recommendations to innovation managers on the choice of different instruments for supporting innovation. The key guiding questions for the comparative analysis were whether the instrument fosters uptake of innovation and whether it promotes inclusive development. A review of the literature was supplemented with a scan of websites for sources of peer-reviewed and gray literature documenting the application of the 12 selected instruments. The study revealed three categories of instruments: (Type A) those that support entrepreneurship; (Type B) those that primarily finance innovation; and (Type C) those that support innovation in real-life contexts. Our analysis indicates that innovation managers and funders need to select instruments that are likely to fit the specific context as well as to address the mandates of their organizations, and in so doing, they must consider how to ensure the sustainability of their investments and meet the needs of their beneficiaries. This review represents one of a handful that have compared the use of multiple instruments across multiple continents in the Global South, and can serve as an important decision-making tool for investors and funders looking to invest in agri-food innovation systems

Book ReviewNature and Farming: Sustaining Native Biodiversity in Agricultural LandscapesBy David Norton and Nick Reid (2013)

CSIRO Publishing, PO Box 1139, Collingwood, Victoria 3066, Australia304 pages, softcoverISBN: 9780643103252. Price AU$69.95African Journal of Range &amp; Forage Science 2013, 30(3): 169–17

Crop–livestock interactions: implications for policy-makers and for farmers

This paper was prepared in response to a paper prepared by Vetter (in this issue) that addressed the issue of policy development related to sustainable management of rangelands. In line with the sentiments of Vetter, policies are understood to guide the allocation of resources. The important contribution that livestock make to rural livelihoods is well recognised and strengthening crop–livestock interactions is seen as an effective way of improving livestock productivity while generally being understood as an effective way to increase agricultural production so as to meet the growing needs of the global population. The use of crop residues by livestock is one specific linkage that offers opportunities, but this could be maximised by increasing the yield and quality of the residues. One key challenge to strengthening crop–livestock interactions is the extent to which arable lands are being abandoned. Efforts need to be made to reverse this situation, which requires a range of technical and social/institutional interventions. Although some policy documents refer to integrated systems and alternative cropping practices, there is limited evidence that this in fact is happening on the ground. Policy needs to support crop–livestock interactions more actively so that on-farm research with farmers, as is happening in Msinga, becomes more widespread.Keywords: crop–livestock, integrated farming, policyAfrican Journal of Range &amp; Forage Science 2013, 30(1&amp;2): 45–5

EditorialAligning policy with the socio-ecological dynamics of rangeland commons

Click on the link to view the editorial. African Journal of Range &amp; Forage Science 2013, 30(1&amp;2): 1–