Development of a private animal health delivery network in North Sumatra,Indonesia

Livestock is one of the growth sectors in the rural economy. In the third world the provision of livestock services for smallholders has generally been in the hands of the governments, leading to erratic, insufficient, and unreliable delivery systems. Especially in cases where the benefits of services accrue to the owners of the animals, privatization of some of the animal services may improve the delivery system. In order to explore the impact of such a private system, a group of sheep farmers in North Sumatra, Indonesia, were organized in an Animal Health Delivery Network (AHDN). The experience with AHDN indicates that the scope of private sector involvement is promising. Farmers were able to recognize the benefits and willing to pay for the drugs. However, they seem to be reluctant to apply the drugs themselves, thereby relying on the help of extension agents and traders. Selling drugs via poultry shops to farmers was not successful because drug wholesaler firms do not make their products available in small quantities. The study confirmed that the role of Government and private sector in the delivery of livestock services needs to be redefined.The authors are all members of the Small Ruminant Collaboration Research Support Program's (SR-CRSP) Economics Project being implemented by Winrock International Institute for Agricultural Development (WI) in the United States and the Center of Research Institutes for Animal Sciences (CRIAS) in Indonesia. Kartamulia was resident scientist at the Animal Research Station in Sei Putih, North Sumatra for the duration of this study under a collaboration agreement with INI ANSREDEF, an Indonesian NGO supporting livestock research and development. Misniwaty is a member of the socioeconomic group at the same station and staff of the Agency of Agricultural Research and Development (AARD). Knipscheer is Winrock's Regional Director for Asia and based in Morrilton, Arkansas.     

Enhanced iron reduction by iron supplement: A strategy to reduce methane emission from paddies

As an option for mitigating methane emissions from rice paddies the effects of ferrihydrite application to an experimental field plot at the beginning of the growth season was studied. Methane emissions during the vegetation period of rice were significantly lower (50%) in the fertilized plot compared to the non-supplemented control plot. Although toxic effects of iron are known to occur with wetland plants including rice, our field experiment showed no deterioration of agrophysiological data. Grain yield, harvest index, and iron content of grains were not different in the two plots. Therefore, we propose that iron application is a suitable strategy to reduce methane emission from rice paddies.     

Displacement imaging in porous media using the line scan NMR technique

Displacement imaging is a recent, powerful NMR method with which distributions of displacements can be acquired of e.g. fluids within a porous medium. Both motion parallel and perpendicular to the flow direction may be observed within a time window of a few milliseconds to several seconds. By combining displacement imaging with the line scan technique, one-dimensionally resolved measurements with a high temporal resolution ( < 1 min) of the spatial dependency of motion can be obtained. Here we present displacement images of flow through two simple model systems for soil: an unconsolidated glass bead water system and a sintered glass bead filter. It is demonstrated that the combination of displacement imaging and spatial resolution along a line is important to access both bulk displacement and local displacements in relation to the local porosity.     

Degradation of S-2-Di-isopropylaminoethyl O-ethyl methylphosphonothioate in soil: Phosphorus-containing products

The degradation of S-2-di-isopropylaminoethyl O-ethyl methylphosphonothioate in humic sand, humic loam and clayey peat has been studied under laboratory conditions. About 90% of the compound disappeared within 2 days and the remainder disappeared more slowly. Ethyl hydrogen methylphosphonate and methylphosphonic acid were identified as the only phosphorus-containing degradation products.     

Electron microscopy of equine respiratory viruses in organ cultures of equine fetal respiratory tract epithelium

Organ cultures of equine fetal tracheal and nasal turbinate epithelium were inoculated with equine influenza virus-A1 (EIV-A1), equine herpesvirus-1 (EHV-1), or equine rhinovirus-1 (ERV-1). Infected organ cultures were processed for scanning and transmission electron microscopy at various intervals and were compared with noninfected controls. Organ cultures inoculated with ERV-1 appeared normal with the exception of rare island-like lesions in infected nasal turbinate. Virus particles were not seen in thin sections of organ cultures infected with ERV-1. The EHV-1 caused extensive loss of the epithelial layer in tracheal and nasal turbinate organ cultures. The classic stages of herpesvirus morphogenesis were seen in thin sections of organ cultures infected with EHV-1. The EIV-A1 caused a scattered loss of cilia that was only apparent in infected tracheal organ cultures. Cilia were also seen bound in bundles. In thin sections, EIV-A1 particles were seen budding from the bases of microvilli.     

Serum haemolytic complement activities in 11 different MHC (B) typed chicken lines

To study the relation between serum complement levels and the chicken MHC (B) complex, complement haemolytic activity was measured in sera from hens from seven pure-bred B-typed White and one Brown Leghorn lines, and three ISA-Warren lines that had been divergently selected for antibody responses to sheep red blood cells (SRBC). Significant differences occurred in the serum haemolytic complement activities, both belonging to the classic (CPW) and the alternative (APW) pathways, among the 11 different haplotyped chicken lines. Hens with high CPW and high APW titres predominantly displayed the B2 or B21 haplotypes. Chickens with low CPW and APW were found in B14 and B15 haplotypes. Haplotype B14 appears to be different in complement levels when present into the pure-bred lines or into the ISA-Warren line selected for low antibody responses to SRBC. Otherwise, the presence of B21 in ISA-Warren line selected for high antibody responses to SRBC does not differ with the B21 in the inbred lines (except in the NL-line for CPW values). In general the haplotypes B2 and B21 are found in chicken lines with enhanced disease resistance, and the B15 haplotype has been connected with enhanced disease susceptibility. Our results suggest that levels of haemolytic complement activity, either from the classical or from the alternative pathways, may underlie part of the immunocompetence ascribed to the MHC (B) complex in chickens.     

Structural requirements for the antimicrobial activity of carvacrol

Carvacrol is a component of several essential oils and has been shown to exert antimicrobial activity. The structural requirements for the activity of carvacrol were determined by comparison to structurally related (nonessential oil) compounds. Removal of the aliphatic ring substituents of carvacrol slightly decreased the antimicrobial activity. The effect of the hydroxyl group of carvacrol on activity could not be determined by simply comparing it to p-cymene, because this compound is immiscible with water; therefore, 2-amino-p-cymene, the amino analogue of carvacrol, which has a similar hydrophobicity and structural characteristics, was used. 2-Amino-p-cymene had similar membrane disruption and bacterial killing characteristics as carvacrol showing that, contrary to previous reports, the hydroxyl group of carvacrol itself is not essential for the antimicrobial activity. However, the observed 3-fold lower activity for 2-amino-p-cymene as compared to carvacrol indicates special features in the antimicrobial mode of action of carvacrol due to the hydroxyl group.     

Display and selection of chicken IgA Fab fragments

Passive immune therapy is regaining interest to prevent and cure infectious diseases both in human and veterinary medicine. Therefore, systems are required that enable efficient targeted selection of antibodies originating from virtually any animal species. Here, a system for the selection of chicken IgA, using phage display, is described. A novel phagemid vector (pChick3) for the display and selection of chicken IgA antibodies in Fab format was developed. The functionality of pChick3 was demonstrated by construction of an immune antibody library using B cells from chickens infected with Eimeria acervulina. From this library, 10 different IgA fragments with specific binding to the E. acervulina antigen mix, the sporozoite or oocyst fractions were selected. These results demonstrate the efficiency and versatility of the pChick3 vector system that can readily be applied to construct libraries and subsequently select antibodies of the alpha isotype against a wide variety of pathogens and parasites.