Haemadsorption inhibition test for the identification of Mycoplasma gallisepticum and Mycoplasma synoviae

Summary

Colonies of the avian mycoplasma strains Mycoplasma gallisepticum S6 and Mycoplasma synoviae WVU 1853 and two Mycoplasma synoviae isolates from this laboratory were shown to be haemadsorption positive for chicken erythrocytes. Three Mycoplasma synoviae isolates from this laboratory proved to be haemadsorption and haemagglutination negative. The haemadsorption of the mycoplasma colonies mentioned above was inhibited with specific antisera of either high or low titre. No cross‐inhibition was observed. It is suggested that this test could be used for a quick tentative identification of the two avian mycoplasmas on primary solid‐medium cultures.     

Additional studies on the therapeutic efficacy of sulphadimidine sodium in experimental Eschericha coli infection of broilers

Summary

In contrast with the recommended dose of 2,000 drinking ppm sulphadimidine sodium in the water for treatment of broilers against colibacillosis,it appeared that under experimental conditions, treatment at 500 ppm (60 mg/kg body weight) gave the best therapeutic effects. At higher concentrations, drinking water consumption and body weight gain were reduced significantly. During treatment high blood plasma‐concentrations were measured.     

Conservation genetics of a rare Gerbil species: a comparison of the population genetic structures and demographic histories of the locally rare Pygmy Gerbil and the common Anderson's Gerbil

Background  

One of the major challenges in evolutionary biology is identifying rare species and devising management plans to protect them while also sustaining their genetic diversity. However, in attempting a broad understanding of rarity, single-species studies provide limited insights because they do not reveal whether the factors that affect rare species differ from those that affect more common species. To illustrate this important concept and to arrive at a better understanding of the form of rarity characterizing the rare Gerbillus henleyi, we explored its population genetic structure alongside that of the locally common Gerbillus andersoni allenbyi. We trapped gerbils in several locations in Israel's western and inner Negev sand dunes. We then extracted DNA from ear samples, and amplified two mitochondrial sequences: the control region (CR) and the cytochrome oxidase 2 gene (CO2).     

Integration of geospatial and cattle nutrition information to estimate paddock grazing capacity in Northern US prairie

Spatiotemporal variability in forage quantity and quality requires that regular assessment is needed of the capacity for grasslands to support livestock nutritional requirements. Current methods for estimating grazing capacity are typically production-based and lack the forage quality data necessary to match nutrients in forage with livestock requirements in real time. This paper describes a method for estimating short-term grazing capacity for small (1–20 ha) paddocks using cattle nutrition and high spatial resolution forage data in Geographic Information Systems (GIS) for mixed-grass prairie. We define grazing capacity as the number of days a specific paddock will support the nutritional requirements of beef cattle. We integrate previously published methods for estimating cattle nutritional requirements, forage quality (crude protein) and forage quantity (phytomass) to estimate grazing capacity based on current standing-crop. The model utilizes high-resolution (<30-m) satellite imagery or field data to estimate short-term grazing capacity for small paddocks. Three versions of the model were evaluated on one paddock under cattle use in 2007. One version was parameterized using data collected on June 22 from the Landsat Thematic Mapper (TM), one version was parameterized using data collected June 23 from the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER), and one version was parameterized using data collected June 20 from field clippings. TM and ASTER versions underestimated grazing capacity by four days while the field version overestimated grazing capacity by one day. Results suggest integration of cattle nutrition and forage data in GIS could assist with stocking rate adjustments, but additional trials are needed.     

Therapeutic efficacy of medicating drinking water with spectinomycin and lincomycin-spectinomycin in experimental Escherichia coli infection in poultry

Although no microbiological activity was found in blood plasma during treatment of broilers through the drinking water with spectinomycin or lincomycin-spectinomycin, these drugs proved highly effective in treating experimentally induced colibacillosis. This efficacy may be produced by a metabolite or a degradation product of spectinomycin that reaches the infection site in the respiratory tract and interferes with adherence of bacteria.     

A Novel Method for Combined Biowaste Stabilization and Production of Nitrate-Rich Liquid Fertilizer for Use in Organic Horticulture

A novel system for organic waste stabilization and reuse, combined with production of nitrate-rich liquid fertilizer was developed by manure digestion followed by volatilization of ammonia-rich gas (originating in manure extract) and its nitrification and recovery. This approach has several advantages, including biowaste stabilization and high recovery (over 60%) of manure N mainly as nitrate which is a better N form for many plants as compared to ammonium as the sole fertilizer N. Moreover, the potential utilization of different wastes as N sources in organic horticulture is possible as well as removal of suspended particles and microorganisms (including pathogens) that might otherwise clog the irrigation system and pose health risks, respectively. In a pilot-scale study, the system yielded several hundred liters of nitrate-rich (ca. 11 g N L⁻¹) liquid fertilizer using guano as substrate. In a fertilization experiment, lettuce fertigated with the nitrate-rich extract exhibited better growth and quality compared to the common organic practice of fertigation with guano extract. The resulting stabilized biowaste was estimated as “low-risk” according to current guidelines and may be used for liming or land application.     

Protection of chicks against Salmonella infantis infection induced by strict anaerobically cultured intestinal microflora

Summary

In two experiments newly hatched broilers were orally inoculated either with intestinal microfloras cultured under different conditions or with a suspension of intestinal homogenate and challenged with high doses (3 x 10⁵ c.f.u. per chick) of Salmonella infantis organisms.

Inocula were prepared from intestinal material of mature SPF WL hens under aerobic or strictly anaerobic conditions (< 5 ppm oxygen), and protected against atmospheric oxygen during storage. A very significant reduction of the number q/Salmonella infantis bacteria in caecal content was achieved one and two weeks after challenge in those groups of chicks which were inoculated with anaerobically cultured flora or with intestinal homogenate. In order to induce protection, obligate anaerobes had to be accompanied by facultative anaerobes. Amprolium or Monensin dit not interfere with protection. Protection induced by intestinal microflora depends on anaerobiosis during preparation, culturing, storage, and application of the protective bacteria. Starvation on the first day of life appeared to have a negative effect on protection.     

Protection of chicks against salmonella infection induced by spray application of intestinal microflora in the hatchery

The efficacy of spray application of intestinal microflora of the adult bird in protection of broilers against salmonella infections was studied in 3 experiments under laboratory and field conditions. In chicks treated soon after hatching (in the hatchers at approximately 30 per cent hatch or in the chick delivery boxes in the hatchery) with crop-caecum homogenate or a mixture of aerobically and strict anaerobically cultured intestinal flora, very good results were achieved. A very obvious protective effect against a high infection dose (3 X 10(6) c.f.u.S. infantis bacteria per chick) and complete protection against natural infection with different salmonella types was induced. A significant improvement of growth rate was observed in broilers treated by spray in the hatchery and reared for 7 weeks under field conditions in an environment heavily contaminated with different salmonella types.     

A method for aseptic culture of bud explants from citrus trees

Culture of citrus bud explants sampled from outdoor trees is sometimes difficult because of contamination not overcome by standard surface-sterilization. An improved method, involving a 5-minute immersion of explants in 80% (v/v) ethanol, which does not interfere with normal explant and callus development, is described in detail.