Estimating the impacts of water pricing on smallholder irrigators in North West Province, South Africa

Worldwide growing water scarcity has increased the call for economic instruments to stimulate rational water use in agriculture. Furthermore, cost-recovery is now widely accepted as a cornerstone of sustainable water management. In many developing countries, where agricultural water use is often still subsidised, water pricing policies are developed for allocating water efficiently and achieving sustainability of water systems. However, the impacts of water pricing policies on irrigation water use and on farm production systems is mostly unknown. We introduce an innovative two-stage methodology that allows estimating these effects at farm level. Applying the method to small-scale irrigators in South Africa, we show that water demand is quite responsive even to small changes in water price. In addition, the introduction of a water price significantly decreases farm profit. This appears to be a problem primarily for the poorer farmers.     

Influence of processing on total,monoglutamate and polyglutamate folate contents of leeks,cauliflower, and green beans

Bioavailability of dietary folate might be impaired by the polyglutamate chain to which approximately 70% of dietary folates are bound. This chain must be removed enzymatically in the intestine before folate is absorbed as a monoglutamate. To increase formation of monoglutamate folate in vegetables, the vegetables were subjected to various processing treatments. Treatments included freezing (-18 degrees C, 16 h) and thawing (4 degrees C, 24 h) and hydrostatic high-pressure treatment (200 MPa, 5 min). Both freezing/thawing and high-pressure treatment increased the proportion of folate in the monoglutamate form in leeks, cauliflower, and green beans 2-3-fold. However, loss of total folate after these treatments was >55%. It is concluded that conversion of folate polyglutamate to the monoglutamate form in vegetables is possible by certain processing treatments. Potentially this could lead to vegetables with higher folate bioavailability. However, to prevent folate loss into processing water, processing in a closed system should be applied.     

Copper in the terrestrial environment: Verification of a laboratory-derived terrestrial biotic ligand model to predict earthworm mortality with toxicity observed in field soils

This study was set up for validation of a regression model to predict mortality in the terrestrial earthworm Aporrectodea caliginosa following exposure to copper. This model was derived from a terrestrial biotic ligand model and incorporates the protective effects of H⁺ and Na⁺ on copper toxicity.Three soil sets were used for the experiments, all of which had a different copper contamination history over more than 20 years and were considered to be aged field soils. The soils were characterized by analysis of various copper pools in the solid phase and in the pore water, analysis of physical and chemical soil properties and by regression analysis. Measured and calculated copper activities (expressed as pCu) correlated reasonably well. Measured copper activities correlated with the total copper concentration in the pore water and the pH. The organic matter in the solid phase had no influence on the pCu in these soil sets.Earthworms were exposed to the soils for 28 days, after which survival was scored. Observed earthworm mortality after 28-days exposure was plotted as a function of the log-transformed difference between predicted (log₁₀ transformed) LC50-values and measured values of pCu for validation of the regression model. The results obtained were in agreement with the assumption that mortality is to be observed in those soils where the predicted LC50 exceeds the measured pCu. However, a structural underestimation of toxicity was apparent, which is most likely due to mixture effects related to the presence of additional substances in field soils. Nevertheless, the trend of the results in the validation tests demonstrates that the newly developed toxicity model is a useful tool in predicting lethality of copper contamination to earthworms in field soils.     

Genetic diversity of livestock-associated MRSA isolates obtained from piglets from farrowing until slaughter age on four farrow-to-finish farms

During a previous longitudinal study, performed on four farrow-to-finish farms (A to D), samples were taken from twelve sows, their offspring, and the environment on various occasions over six months to study the MRSA presence. During the present study, a selection of the obtained MRSA isolates were typed by multiple-locus variable-number tandem-repeat analysis (MLVA), Pulsed Field Gel Electrophoresis (PFGE), spa typing, and SCCmec typing to study the genetic diversity of LA-MRSA isolates and to determine possible MRSA sources for pig(let)s. PFGE, spa typing, and SCCmec typing revealed the presence of one or few dominant genotype(s) per farm. In contrast, 212 MLVA types were detected on the four farms, forming one cluster on farm A, three on farm B, four on farm C and two on farm D. The genotype, found on farm A was unique for this farm. Farms B, C and D shared one cluster. In general, MLVA types from these clusters were isolated from piglets, sows, and the environment on various sampling events. Piglets carried MLVA types both related and unrelated to their mother sows’ MLVA types at farrowing and onwards. In conclusion, molecular typing revealed that within a farm one or a few dominant strain(s) are widespread. Potential MRSA sources for piglets were mother sows, the environment and other piglets.

Electronic supplementary material

The online version of this article (doi:10.1186/s13567-014-0089-4) contains supplementary material, which is available to authorized users.     

Oncocytoma in the mandibular salivary gland of a cat

A cat was referred for investigation of a soft tissue mass caudal to the left mandible. Initial investigations suggested a malignant salivary gland tumour, and the mass was removed by extracapsular resection of the mandibular gland. Histopathology showed an oncocytoma within the salivary gland. An oncocytoma is a neoplastic transformation of oncocytes. Oncocytes are cells with a small nucleus and intense eosinophilic granular cytoplasm due to numerous mitochondria, which proliferate during ageing in exocrine and endocrine glandular tissues. Physiological proliferation occurs next to oncocytosis, oncocytoma, and oncocytic carcinoma. This is the first report of an oncocytoma in a feline mandibular salivary gland, and the first report of long-term survival after surgical removal.     

A seasonal model of contracts between a monopsonistic processor and smallholder pepper producers in Costa Rica

We model the contractual arrangements between smallholder pepper (Piper nigrum L.) producers and a single processor in Costa Rica. Producers in the El Roble settlement sell their pepper to only one processing firm, which exerts its monopsonistic bargaining power by setting the purchase price of fresh pepper. It also sets quality norms that result in the rejection of considerable amounts of the pepper produced by individual farmers. Because the firm is not able to produce its own raw pepper and requires a sufficiently stable flow of the fresh product to be processed into high quality white pepper, it usually relies on contracts with individual smallholders. Nevertheless, the latter considered collective marketing and took the initiative to propose a group contract with the firm. Such a contract increases the producers’ bargaining power vis-à-vis the processing firm and reduces rejection rates as more care is taken when transporting the pepper to be processed. Although a group contract causes the firm to lose part of its monopsonistic rents, it also reduces transaction costs as only one contract must be negotiated instead of many. Both the firm and the producers benefit, yet from the very beginning of the association, the producers breached the group contract. We have used a mixed integer linear model which, given a set of constraints, maximises the weighted sum of the expected incomes of the firm and producers. We modelled the contract chosen by the firm and the producers according to the conditions included, such as minimum income requirements and risk considerations of both processor and farmers. We calibrated the model with data from pepper producers and the firm in El Roble. The results show that at different fresh pepper prices, the contract preferred changes with the bargaining power attributed to the firm and smallholders. However, in general, it can be concluded that fresh pepper prices high enough to cover the costs, for the farmers, of a group contract lead to lower rejection rates, and thus to more pepper of an acceptable quality, increasing the incomes of both the processor and the farmers. This is also of interest in agricultural policy-making.     

Policy reforms,rice production and sustainable land use in China: A macro–micro analysis

This paper presents a macro–micro analysis of the impact of policy reforms in China on agricultural production, input use and soil quality change for a major rice-producing area, namely Jiangxi province. This is done in three steps. First, a quantitative assessment is made of the impact of market liberalization policies on the economic environment of farm households in Jiangxi province. Econometric analyses based on provincial, national and world market data are used to explain changes in rice and fertilizer prices in Jiangxi province over time. Next, the impact of China’s recent income support policy and latest price trends on farm household choices with respect to activity choice (particularly rice and livestock) and input use (fertilizers, pesticides, manure) is assessed for two villages with different degrees of market access in north-east Jiangxi province. Two village-level general equilibrium models are used to analyse household decision-making and interactions between households within these villages. The parameters are estimated and calibrated from an extensive survey held in these villages in the year 2000. Finally, the impact of land tenure policy on farm management decisions (labour, manure and chemical input use), soil quality (available P and K and total N and C) and rice yields is analysed through an econometric analysis of plot-level data for three villages. Two-stage least squares (2SLS) is used to control for interactions with yields and for feedbacks towards input use. The paper ends with a number of suggestions for policy adjustments that would reduce the problem of natural soil compaction in the research area.     

Gastric granulomatous cryptococcosis mimicking gastric carcinoma in a dog

Summary

An ulcerated lesion resembling a tumour in the lesser curvature of the stomach of a 3‐year‐old male Dobermann pinscher was found to be caused by Cryptococcus neoformans. The dog had been vomiting for two months and had slight leucocytosis and anaemia. Biopsies of the ulcerated lesion revealed granulomatous inflammation and many cryptococci, which were particularly prominent in PAS and mucicarmine stained sections. No other lesions were found at necropsy.