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Two recent studies have suggested that divergent mitochondrial lineages may be present within spirostreptid genera such as Bicoxidens Attems, 1928. Bicoxidens, similar to many other endemic soil invertebrates, exhibits low dispersal capabilities and strict microclimate habitat preferences, attributes that often lead to geographic isolation. Given that prolonged geographic isolation often lays the foundation for population genetic differentiation, genetic divergence and possibly speciation, there was good reason to suspect that Bicoxidens may consist of several distinct lineages. On this basis, the mitochondrial cytochrome c oxidase subunit 1 (COI) was used to reconstruct the phylogeny of Bicoxidens and reveal divergent lineages within the genus. Maximum likelihood and Bayesian inference analyses recovered a paraphyletic Bicoxidens phylogram with divergent lineages present in three species – B. friendi, B. flavicollis and B. brincki – suggesting high genetic diversity within the genus. Bayesian genetic cluster analyses suggested the presence of multiple distinct mitochondrial lineages within the genus with four identified in B. flavicollis alone. It was therefore concluded that the divergent lineages observed among Bicoxidens populations may suggest the presence of hidden species. 相似文献
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Tawanda Marandure Godswill Makombe Baldwin Nengovhela Phillip Strydom Voster Muchenje 《African Journal of Range and Forage Science》2016,33(3):199-206
The objective of this study was to examine the factors influencing smallholder producers’ potential to sell cattle and identify marketing opportunities for sustainable beef production in South Africa. A total of 95 structured questionnaires was administered to the Ncorha and Gxwalibomvu communities in the Eastern Cape province of South Africa. Average cattle herd size per household was higher (P < 0.05) in Ncorha (13.7 ± 1.9) than in Gxwalibomvu (11.3 ± 1.9). The logit model showed that households with few members, young farmers, Christians, large cattle herds, low income levels and access to extension services had high potential to sell cattle compared with other households (P < 0.05). Beef branding (～40% of respondents from each community), feedlotting (～30%), group marketing (～25%) and forward contracting (>5%) were mentioned as potential strategies for improving commercial marketing of cattle in the studied areas. Most producers (70%) indicated their potential and willingness to participate in developing a natural pasture-fed beef brand. Overall, commercial marketing of beef cattle raised on communally owned natural pastures in the surveyed areas in South Africa was largely determined by farmer’s demographic characteristics, cattle herd size and access to extension services with branding and feedlotting as the major opportunities for improving sales. 相似文献
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Tawanda Marandure Godswill Makombe Baldwin Nengovhela Phillip Strydom Voster Muchenje 《African Journal of Range and Forage Science》2016,33(3):207-214
Beef traders’ and consumers’ perceptions on the development of a natural pasture-fed beef (NPB) brand by smallholder cattle producers were investigated. In total, 18 meat traders (five abattoirs and 13 beef retailers) and 155 beef consumers were interviewed using structured questionnaires. All meat traders had the potential but were not willing to support the development of a NPB brand citing smallholder farmers’ limited ability to supply sufficient volumes of high-quality cattle. Consumers (81%) were prepared to purchase NPB upon availability on the market but were not willing (80%) to pay a brand premium. Logistic regression model results showed that consumers’ willingness to buy NPB and pay a premium were influenced (P < 0.05) by gender, household size, income source, meat preference, meat consumption frequency, money spent on beef, frequency of beef purchases and consumption. Overall, beef traders and consumers held positive impressions regarding the development of a NPB brand by smallholder cattle producers but were not willing to support its development. Positive impressions held by value chain partners on the development of a NPB brand provide a basis for advancing development of a NPB brand. Initial efforts should enhance farmers’ capacity to supply sufficient volumes of high-quality cattle. 相似文献
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