Acute Phase Protein Levels in Rabbits with Suspected Encephalitozoon cuniculi Infection

The objective of this study was to evaluate the application of acute phase protein assays for C-reactive protein (CRP), haptoglobin (HP), and serum amyloid A (SAA) in the diagnosis of Encephalitozoon cuniculi (ECUN) infection in pet rabbits. Serum samples from 48 pet rabbits were submitted from veterinary clinics within the United States. Participating veterinarians completed a questionnaire that was used to classify rabbits as either non-ECUN suspect (n = 19) or suspected of having ECUN infection (n = 29). A previously described enzyme-linked immunosorbent assay diagnostic test was used to detect immunoglobulin G (IgG) titers against ECUN. Samples were additionally tested for levels of CRP, HP, and SAA. A nearly 10-fold mean increase in CRP levels was observed in the ECUN-suspect group. This increase was significant (P < 0.05). There was no significant difference in HP or SAA levels between the clinical groups. These data support the use of CRP as an adjunct test in the diagnosis of ECUN infection in pet rabbits.     

Development of a gene-based marker correlated to reduced aflatoxin accumulation in maize

Aflatoxins are carcinogenic and toxic metabolites produced by the fungus Aspergillus flavus during infection of maize (Zea mays L.) and other seed oil crops. Climatic conditions in the southeastern United States favor A. flavus infection and aflatoxin contamination in maize, making it a major issue for farmers in the region. One of the most promising avenues to combat aflatoxin contamination is the development of resistant maize lines. However, this has proven difficult due to a lack of reliable markers for resistance. Previous studies have identified candidate genes that were differentially expressed in response to A. flavus infection. One gene, encoding a chloroplast precursor, was found to contain multiple polymorphisms that were used to design a marker designated Mississippi Marker 1 (MpM1). The marker differentiates between the “resistance” and “susceptible” forms of the allele. This marker was used to screen three populations of F_2:3 mapping families, where it was found to map to chromosome 4 and was associated with a significant effect for resistance to aflatoxin accumulation in the Mp313E × B73 mapping population. Furthermore, the marker MpM1 identified a previously unknown quantitative trait loci for resistance to aflatoxin accumulation on maize chromosome 4. MpM1 is the first gene-based marker developed specifically for resistance to aflatoxin accumulation in maize and can now be integrated into existing marker assisted selection programs aimed at incorporating resistance into elite maize breeding lines.     

Behavioural indicators of welfare in farmed fish

Behaviour represents a reaction to the environment as fish perceive it and is therefore a key element of fish welfare. This review summarises the main findings on how behavioural changes have been used to assess welfare in farmed fish, using both functional and feeling-based approaches. Changes in foraging behaviour, ventilatory activity, aggression, individual and group swimming behaviour, stereotypic and abnormal behaviour have been linked with acute and chronic stressors in aquaculture and can therefore be regarded as likely indicators of poor welfare. On the contrary, measurements of exploratory behaviour, feed anticipatory activity and reward-related operant behaviour are beginning to be considered as indicators of positive emotions and welfare in fish. Despite the lack of scientific agreement about the existence of sentience in fish, the possibility that they are capable of both positive and negative emotions may contribute to the development of new strategies (e.g. environmental enrichment) to promote good welfare. Numerous studies that use behavioural indicators of welfare show that behavioural changes can be interpreted as either good or poor welfare depending on the fish species. It is therefore essential to understand the species-specific biology before drawing any conclusions in relation to welfare. In addition, different individuals within the same species may exhibit divergent coping strategies towards stressors, and what is tolerated by some individuals may be detrimental to others. Therefore, the assessment of welfare in a few individuals may not represent the average welfare of a group and vice versa. This underlines the need to develop on-farm, operational behavioural welfare indicators that can be easily used to assess not only the individual welfare but also the welfare of the whole group (e.g. spatial distribution). With the ongoing development of video technology and image processing, the on-farm surveillance of behaviour may in the near future represent a low-cost, noninvasive tool to assess the welfare of farmed fish.     

Breaking wheat yield barriers requires integrated efforts in developing countries

Most yield progress obtained through the so called "Green Revolution", particularly in the irrigated areas of Asia, has reached a limit, and major resistance genes are quickly overcome by the appearance of new strains of disease causing organisms.New plant stresses due to a changing environment are difficult to breed for as quickly as the changes occur.There is consequently a continual need for new research programs and breeding strategies aimed at improving yield potential, abiotic stress tolerance and resistance to new, major pests and diseases.Recent advances in plant breeding encompass novel methods of expanding genetic variability and selecting for recombinants, including the development of synthetic hexaploid, hybrid and transgenic wheats.In addition, the use of molecular approaches such as quantitative trait locus(QTL) and association mapping may increase the possibility of directly selecting positive chromosomal regions linked with natural variation for grain yield and stress resistance.The present article reviews the potential contribution of these new approaches and tools to the improvement of wheat yield in farmer's fields, with a special emphasis on the Asian countries, which are major wheat producers, and contain the highest concentration of resource-poor wheat farmers.     

Growth and yield of corn grown on two alluvial soils of Louisiana applied with different phosphorus rates

The influence of soil properties on phosphorus (P) availability of Louisiana alluvial soils is not fully understood. A pot experiment was conducted in 2011 to evaluate the effect of different P fertilizer rate (0, 34, 67, 101 and 134 kg P₂O₅ ha^?1) on corn growth and development on Perry clay and Commerce silt loam (sil) soils and relate Mehlich-3 and Bray-2 soil test P values with yield, total biomass, and P uptake of corn. The Bray-2 P values were six times higher than Mehlich-3 P values for Commerce sil while they were similar for Perry clay. Bray-2 and Mehlich-3 extractable-P of both soils increased with increasing P rate but only corn grown on Perry clay responded to P rate (P < 0.05). Implementation of appropriate testing procedure for estimating plant-available P in soil is an important component of effective P fertilization guidelines for corn.