Correlation Between SRID and ELISA of Serum Immunoglobulin G Concentrations in Quarter Horse Mares and Their Foals From Birth to Weaning

Failure of passive transfer (FPT) is a life threatening condition in foals and occurs when immunoglobulin G concentrations (IgG) are below 400 mg/dL and partial failure of passive transfer (PFPT) occurs when IgG concentrations are between 400-800 mg/dL. An IgG concentration of greater than 800 mg/dL is considered sufficient to protect the foal against pathogens. The standard method of determining antibody concentrations is Single Radial Immunodiffusion (SRID). However, this method requires an 18 h incubation and is not time efficient. Enzyme Linked Immunosorbant Assays (ELISA) only require a 4 h incubation period to detect IgG concentrations. The purpose of this study is the correlate the immunoglobulin G concentrations of mares and foals derived from ELISA with a previous study conducted using SRID. A low correlation between ELISA and SRID was found and within blocks, foals displayed the highest correlations.No embargoAcademic Major: Animal Science

Pruning strategies for reducing crop suppression and producing high quality timber in smallholder agroforestry systems

In the Philippines, smallholder farmers have become major timber producers and trees planted on farms are an important source of raw materials and income for them and for the local timber industry. The smallholder mode of timber production has several advantages over traditional reforestation. The frequent and intensive tending operations (land cultivation, weeding and fertilization) for annual intercrops improve tree survival and growth. Intercropping reduces tree establishment and weeding costs because these are charged to annual crop production. The cropped alleys between tree lines function as effective firebreaks. However, the planting of timber trees in association with light-demanding annual crops often leads to a drastic suppression in crop production as a result of competition for both above- and below-ground resources. With few exceptions, the most common timber trees promoted for farm forestry have been reported to decrease yields of associated crops. Therefore, concerns have been raised over the sustainability and suitability of tree farming for resource-poor farmers. Branch pruning effectively reduces light interception by the tree canopy, and thus prolongs the number of years that annual crop production can be practiced. However, to minimize crop yield suppression, farmers often practice intensive pruning annually before planting annual crops. Intensive pruning may enhance crop yield, but it is incompatible with commercial timber production because the growth rate and quality of the overstorey timber trees are severely reduced. This paper reports the results of on-farm trials conducted to assess the effects of four pruning levels on maize grain yield and also on tree growth and form. Plots consisted of three rows of the timber tree Gmelina arborea planted at 1 x 10 m with maize planted in the 10 m alleys during seven cropping seasons. The study shows that high pruning intensity (retaining a live crown ratio of 20−30%) results in significantly higher maize grain yields but reduced tree diameter. In economic terms, these higher maize grain yields are not enough to compensate for the costs of pruning and the lower market value of smaller-diameter timber. Therefore, if crop production is a priority, tree farmers should plant timber species that are less competitive or plant trees at low densities in other farm niches away from crops

The Fruits and Vegetables Industry in Indonesia: Production and Limited Access to Market

Smallholder producers of fruits and vegetables in the Nanggung sub-district of West Java, Indonesia practice a multicropping system of agriculture on less than two acres of land. Agricultural practices in this area are still crude, with little or no inputs such as fertilization or modern irrigation. When water is available, the furrow irrigation system is used at best. Although banana is one of the income-generating crops, farmers grow it in combination with other fruits such as durian, mangosteen, rambutan, jackfruit, and with vegetables such as chili peppers, tomatoes, sweet corn, and green beans under non-intensive management. Although market-survey reports show that the demand for these fruits and vegetables is greater than the supply, the farmers not only have limited access to markets but produce inferior quality and limited quantity (Fonsah 2003). Due to these limitations, this study is aimed at developing new markets, creating new distribution systems and market channels, and seeks ways to improve those already existing.Agribusiness, Crop Production/Industries, Marketing,

The management of tree genetic resources and the livelihoods of rural communities in the tropics: non-timber forest products, smallholder agroforestry practices and tree commodity crops

Products and services provided by trees in forests and farmland support the needs and promote the wellbeing of hundreds of millions of people in the tropics. Value depends on managing both the diversity of tree species present in landscapes and the genetic variation within these species. The benefits from trees and their genetic resources are, however, often not well quantified because trade is frequently outside formal markets, there is a multiplicity of species and ways in which trees are used and managed, and genetic diversity within species is frequently not given proper consideration. We review here what is known about the value of trees to rural communities through considering three production categories: non-timber products harvested from trees in natural and managed forests and woodlands; the various products and services obtained from a wide range of trees planted and/or retained in smallholders’ agroforestry systems; and the commercial products harvested from cultivated tree commodity crops. Where possible, we focus on the role of intra-specific genetic variation in providing support to livelihoods, and for each of the three production categories we also consider wider conservation and sustainability issues, including the linkages between categories in terms of management. Challenges to ‘conventional wisdom’ on tree resource use, value and management – such as in the posited links between commercialisation, cultivation and conservation – are highlighted, and constraints and opportunities to maintain and enhance value are described

Sandalwood as a Component of Agroforestry: Exploration of Parasitism and Competition with the Wanulcas Model

Sandalwood is an important component of agroforestry systems in the drier Eastern parts of Indonesia, although its value to farmers is still limited by existing policies and regulation of marketing. As a relatively slow growing root parasite, sandalwood will interact with other components in a complex pattern of competition and host-parasite relationships, depending on root distribution and rooting depth of potential hosts. We describe a number of modifications to the generic tree-soil-crop simulation model WaNuLCAS, that allow exploration of the transition between parasitism and competition. The key variable in this transition is the effectiveness of formation of the parasitic link for all situations where roots of the host and parasite occur in the same volume of soil. At low values of this effectiveness competition dominates, at higher values sandalwood will weaken the host, until it effectively kills it, leading to an optimum response of sandalwood to the effectiveness parameter. Unresolved questions in the formulation of the model are the lifespan of parasitized roots and the question whether or not sandalwood will allocate energy resources for maintenance respiration of host roots after the formation of haustoria. The'desk study' reported here was intended to focus subsequent field studies on these unresolved issues

Genetic diversity of the rain tree (Albizia saman) in Colombian seasonally dry tropical forest for informing conservation and restoration interventions

Albizia saman is a multipurpose tree species of seasonally dry tropical forests (SDTFs) of Mesoamerica and northern South America typically cultivated in silvopastoral and other agroforestry systems around the world, a trend that is bound to increase in light of multimillion hectare commitments for forest and landscape restoration. The effective conservation and sustainable use of A. saman requires detailed knowledge of its genetic diversity across its native distribution range of which surprisingly little is known to date. We assessed the genetic diversity and structure of A.saman across twelve representative locations of SDTF in Colombia, and how they may have been shaped by past climatic changes and human influence. We found four different genetic groups which may be the result of differentiation due to isolation of populations in preglacial times. The current distribution and mixture of genetic groups across STDF fragments we observed might be the result of range expansion of SDTFs during the last glacial period followed by range contraction during the Holocene and human‐influenced movement of germplasm associated with cattle ranching. Despite the fragmented state of the presumed natural A. saman stands we sampled, we did not find any signs of inbreeding, suggesting that gene flow is not jeopardized in humanized landscapes. However, further research is needed to assess potential deleterious effects of fragmentation on progeny. Climate change is not expected to seriously threaten the in situ persistence of A. saman populations and might present opportunities for future range expansion. However, the sourcing of germplasm for tree planting activities needs to be aligned with the genetic affinity of reference populations across the distribution of Colombian SDTFs. We identify priority source populations for in situ conservation based on their high genetic diversity, lack or limited signs of admixture, and/or genetic uniqueness