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Dairy herd structures and raising of replacement heifers on smallholder farms in the Kenya highlands
No full textHerd dynamics of smallholder dairy in the Kenya highlands
No full textSmallholder dairy farmers in the Kenya highlands generally intensify their farming systems by integrating dairy with crop production and shifting from free-grazing to semi-zero- or zero-grazing. They consequently change the breed composition, size and structure of their herds with resultant change in herd demographic rates. The intensification of smallholder dairying has underpinned changes in the farming systems to sustain more intensive land use and support more people per unit area of land in smallholder households. However, the concern is whether smallholders will continue to benefit from dairying through continued intensification when facing the pressures of continuously shrinking landholdings, worsening soil fertility and reduced access to formerly public delivered livestock input and output services, while imported nutrients remain relatively low and non-agricultural job opportunities remain lacking. The objective of this study was therefore to quantify the consequences of the intensification of farming systems in the Kenya highlands on the dynamics of smallholder dairy herds in order to better understand the constraints to, and opportunities for, the continued intensification of smallholder dairying. Data collection was through a random stratified cross-sectional survey of smallholder households. Data from the cross-sectional survey sample were complemented with additional information from longitudinal and targeted semi-structured interviews, which involved a randomly selected sub-sample of the previous cross-sectional survey. The drivers of intensification of smallholder dairying were identified and the relative changes were quantified at the level of the farms and farming systems. Intensification requires increased use of external resources including sources of replacement animals, feed resources, animal health and breeding services and credit to sustain the herd population and production. Prospects for maintaining and expanding smallholder dairying in the Kenya highlands depend upon the proportion of free-grazing farms maintained within the farming systems, because these supply semi-zero- and zero-grazing farms with dairy replacements. The rationale underlying smallholders' breeding decisions is based on multiple objectives of more milk, adaptability to local feed conditions and diseases and the provision of non-marketed production such as manure, insurance and financing roles of cattle. Feeding interventions to support continued intensification of smallholder dairying must be within the context of the household's economy, which is characterised by limited cash flow and low risk bearing capacity. Smallholders need affordable working capital to sustain intensification with use of external resources. Solutions to constraints of intensification must concurrently involve both technical and institutional innovations that may encourage greater complementarities and stratification in the dairy sub-sector.</p
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
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