Prevalence of cryptosporidiosis in dairy cattle,cattle-keeping families,their non-cattle-keeping neighbours and HIV-positive individuals in Dagoretti Division,Nairobi, Kenya

The breeding of wild animals for commercial purposes is becoming more frequent nowadays. This situation has led to an increase in contact rates between wild and domestic animals, with subsequent reciprocal transmission of parasites. In this study, we characterized the gastrointestinal and blood parasites of a group of 15 semi-captive guanacos (Lama guanicoe). We characterized gastrointestinal parasites by analyzing fecal samples through the sedimentation–flotation technique and hemoparasites by using blood smears stained with Giemsa. We found several gastrointestinal parasites including Nematoda and protozoans. The most frequently found parasites were Nematodirus sp. and Eimeria sp. In contrast with previous studies, neither Cestoda nor Fasciola were found. The only hemoparasite detected was Mycoplasma haemolamae, a parasite already described in llamas and alpacas. We conclude that the most frequent gastrointestinal parasites of semi-captive guanacos were nematodes and protozoans. Also, the hemoparasite M. haemolamae seems to be prevalent among captive populations of South American camelids. Finally, captive guanacos share several parasites with the traditional livestock. Therefore, keeping captive or semi-captive guanacos without an adequate sanitary protocol might have adverse consequences to adjacent traditional cattle farming and/or for wild animals.     

Camel Streptococcus agalactiae populations are associated with specific disease complexes and acquired the tetracycline resistance gene tetM via a Tn916-like element

Camels are the most valuable livestock species in the Horn of Africa and play a pivotal role in the nutritional sustainability for millions of people. Their health status is therefore of utmost importance for the people living in this region. Streptococcus agalactiae, a Group B Streptococcus (GBS), is an important camel pathogen. Here we present the first epidemiological study based on genetic and phenotypic data from African camel derived GBS. Ninety-two GBS were characterized using multilocus sequence typing (MLST), capsular polysaccharide typing and in vitro antimicrobial susceptibility testing. We analysed the GBS using Bayesian linkage, phylogenetic and minimum spanning tree analyses and compared them with human GBS from East Africa in order to investigate the level of genetic exchange between GBS populations in the region. Camel GBS sequence types (STs) were distinct from other STs reported so far. We mapped specific STs and capsular types to major disease complexes caused by GBS. Widespread resistance (34%) to tetracycline was associated with acquisition of the tetM gene that is carried on a Tn916-like element, and observed primarily among GBS isolated from mastitis. The presence of tetM within different MLST clades suggests acquisition on multiple occasions. Wound infections and mastitis in camels associated with GBS are widespread and should ideally be treated with antimicrobials other than tetracycline in East Africa.     

Filamentous fungi in wrapped forages determined with different sampling and culturing methods

The use of wrapped forage bales with high dry‐matter (DM) content implies risk of fungal growth inside the wrapping, and impaired feed quality. Since fungi may be unevenly distributed in bales, the method of sampling can influence the outcome of the analysis. Three common sampling methods for detection of fungi in wrapped forage were compared: direct plating of visible mouldy patches on bale surfaces (Method I), direct plating of pieces of foliage from drilled core samples (Method II) and quantitative analysis dilution series of drilled core samples (Method III). All samples were cultured on two media at two temperatures. Samples were collected from 124 farms in Sweden and Norway. Using Methods I, II and III, fungi were detected on 52%, 77% and 56% of the farms respectively. Fifty‐two fungal species were identified using a combination of culturing and molecular methods. The most predominant species were Arthrinium spp., found on 55% of the farms, followed by Penicillium roqueforti at 48% of the farms. Incubation at 25°C resulted in higher numbers of all genera, except Aspergillus, compared to incubation at 37°C. The different methods of sampling and culturing did not identify the same fungal species within the same bale. Analysing one bale per farm resulted in detection of less than half the number of species compared to analysing three bales. Of the sampling and culturing methods compared, direct plating of drilled core samples cultivated at malt extract agar at 25°C performed best in terms of qualitative analysis of fungi species.     

Glacially abraded rock flour from Greenland: Potential for macronutrient supply to plants

Rock flour (RF) is a fine‐grained material produced naturally by glacial movement and resulting bedrock abrasion. In Greenland fluvial transported RF from the inland ice sheet sediments in riverbeds and marine outflows. This fine‐sized RF (50% < 9.8 µm) has a high reactivity and may therefore potentially be used to rejuvenate nutrient poor soils and provide nutrients to plants. The aim of this study was to evaluate the ability of a RF from Greenland to supply P, K, Mg, and S to plants. A double‐pot system was used, in which ryegrass (Lolium perenne L.) could take up nutrients from both a hydroponic solution and a soil‐compartment with or without RF amendment; a soil mixture or pure sand was used in the soil‐compartment to estimate RF‐soil interaction effects. Omission of single nutrients from the hydroponic solution allowed assessment of which nutrients the RF in the soil‐compartment was able to supply. Ryegrass biomass was harvested four times during 62 days. We found that RF could supply K continuously to plants grown in soil or sand, but insufficient to fully circumvent K deficiency. During 62 days 5.8% and 4.3% of the applied K from RF was accumulated in the aboveground plant tissue in soil and sand, respectively. Mg was supplied from RF to plants in sand, but no significant effects were observed in soil, possibly due to background soil Mg availability. The amounts of P and S supplied to plants were insignificant. These results indicate the potential of Greenland RF to act as a slow release K and Mg fertilizer.     

First report of Cryptosporidium deer-like genotype in Kenyan cattle

The objective of the study was to identify Cryptosporidium genotypes from feces collected from urban and peri-urban dairy cattle in Nairobi, Kenya, in order to determine their zoonotic potential. DNA was extracted from 34 samples that were diagnosed positive by the modified Ziehl-Neelsen technique. Two Cryptosporidium isolates examined at the 18S rRNA locus were identified as the deer-like genotype by DNA sequencing. As public health officials are facing the difficult decision whether to allow urban livestock production because of its economic benefits and a livelihood asset to the urban communities, or to ban it for its public health risks, the finding of non-zoonotic genotypes in a smallholder dairy system has significant public health as well as economic implications that merit further investigation.     

Assessment of in vitro interferon-gamma responses from peripheral blood mononuclear cells of cattle infected with Mycoplasma mycoides ssp. mycoides small colony type

Contagious bovine pleuropneumonia (CBPP) is a lung disease caused by the bacterial pathogen Mycoplasma mycoides ssp. mycoides small colony type (MmmSC). It has been spreading due to a number of factors including poor vaccine efficacy and poor sensitivity of current diagnostic tests. The purpose of this study was to assess interferon gamma (IFN-gamma) release after stimulation of peripheral blood mononuclear cells (PBMC) from experimentally infected cattle. PBMC collected from 15 artificially infected animals were incubated with different concentrations of total MmmSC antigen. After 72h of incubation the IFN-gamma release was measured and found to be elevated in 11 animals. We did not observe a correlation between IFN-gamma release of animals with and without pathomorphological gross lesions. Therefore, our data do not confirm a role for CD4 T-lymphocytes in protection, since there is no correlation between IFN-g secretion (supposed to be mainly derived from CD4 T-cells) and disease severity. Additionally, we applied immunocytochemistry on affected lung tissue and detected no build up of T-lymphocytes (CD4 T-cells, CD8 T-cells) but a high presence of myeloid cells.     

Cervical thymoma originating in ectopic thymic tissue in a cat

Abstract: An 11‐year‐old female spayed domestic shorthair cat was referred to The Ohio State University Veterinary Teaching Hospital (OSU‐VTH) for evaluation of a 6 × 4 × 3.5 cm mass in the left midcervical region causing increased respiratory sounds and lateral deviation of the trachea. A fine needle aspirate of the mass was obtained before referral and the cytology results were compatible with a reactive lymph node. Immunocytochemistry showed increased numbers of CD3+ T lymphocytes and small numbers of CD20+ and CD79a+ medium to large lymphocytes. Differential diagnoses from the referral pathologist were T‐cell‐rich B‐cell lymphoma and feline Hodgkin's‐like lymphoma. A subsequent fine needle aspirate performed at the OSU‐VTH showed similar results. On flow cytometry the majority of cells were CD3+ T lymphocytes that were double positive for CD4 and CD8 (73%), compatible with either a double‐positive (CD4+CD8+) T‐cell lymphoma or lymphocytes from ectopic thymic tissue. The mass was surgically removed. Histopathology and immunohistochemistry of the mass revealed a predominant population of CD3+ small lymphocytes and small numbers of medium to large lymphocytes with moderate anisocytosis and anysokaryosis. A population of cytokeratin‐positive epithelial cells surrounded small microcystic structures filled with eosinophilic material and structures interpreted as Hassall's corpuscles. These findings were consistent with thymic tissue and a diagnosis of ectopic thymoma was made. PCR results for lymphocyte antigen receptor rearrangement (PARR) were negative. The cat had no evidence of disease 16 months after removal of the mass. To our knowledge this is the first report of an ectopic cervical thymoma in a cat. The clinical and diagnostic features of this unusual case will be useful in helping veterinarians and pathologists obtain a presurgical diagnosis and establish a prognosis for similar lesions.