Relationship between teat morphological traits and subclinical mastitis in Frieswal dairy cows

The present study was aimed to investigate the relationship between selected morphological traits of teat and subclinical mastitis (SCM) in Frieswal crossbred dairy cows. A total of 1040 quarters from 261 lactating cows were evaluated for teat shape (bottle/fleshy/collapsed/conical/normal/pencil and short), teat-end shape (dished/flat/funnel/pocketed/pointed and rounded), teat orientation (aligned/misaligned) and teat position (front and rear; left-sided and right-sided). Each udder quarter was screened with California Mastitis Test (CMT) for the purpose of defining quarter health status. Data were analysed using Chi-square test and multivariable logistic regression procedure. An overall prevalence of SCM (CMT positive) at quarter level was 30.6%. Most of the teats had normal or cylindrical shapes (48%), dished teat-ends (40.7%), and aligned (central or squared) in orientation (65%). At bivariable level, significant association of SCM with teat shape, teat position, teat orientation, parity, and stage of lactation was observed (P < 0.05 to P < 0.001). Teat-end shapes showed some association with SCM (P = 0.07). Results of multivariable analysis showed that pencil-shaped teats were least associated with SCM (P < 0.05) as compared to other teat shapes. Prevalence of SCM was also higher in rear teats (P = 0.015), misaligned teats (P = 0.01), and cows in second or higher parities (P < 0.01) and late stage of lactation (P < 0.001). The results of the present study indicate that selected morphological traits of teat are associated with SCM in Frieswal crossbred cows; therefore, selection towards desirable morphological traits could help reduce mastitis in this breed.     

Antibody response of cattle to rinderpest vaccine

Antibody production was studied in cattle infected with rinderpest vaccine virus. Vaccinated cattle produced both IgM and IgG serum antibodies. The IgG antibodies were mainly those of IgG2 subclass. No IgA antibody response was detected in vaccinated animals.     

Effect of organic amendments on uptake of selenium and biochemical grain composition of wheat and rape grown on seleniferous soils in northwestern India

Crops grown in seleniferous soil may accumulate selenium (Se) to levels considered highly toxic for animal and human consumption. Furthermore, higher Se content in plant tissues leads to considerable deterioration in product quality. Application of organic amendments plays an important role in improving soil physical, chemical, and biological conditions and influencing nutrient availability. A field trial was conducted to evaluate the effect of organic amendments, namely poultry manure (PM), sugar cane press mud (SCPM), and farmyard manure (FYM), on Se uptake and grain quality of wheat and oilseed rape grown on a seleniferous soil in Punjab, India. Selenium accumulation by wheat and oilseed rape grains decreased significantly (75%–95%) with the application of PM and SCPM, while FYM application resulted in a significant decrease (23%) only in case of wheat grains. The amount of Se associated with seed proteins varied in proportion to its uptake under different treatments. Quality of wheat grains improved considerably with respect to total soluble sugars, reducing sugars, starch, lipids, and sulfur concentrations only after application of SCPM and PM. Treating a Se‐contaminated soil with organic amendments significantly increased the oil concentration and changed the proportion of various fatty acids in rape grains. It is concluded that applying organic amendments to Se‐contaminated soils can alleviate the deleterious effects of Se and restore the nutritional quality of grains.     

Genetic mapping of seedling and adult plant stem rust resistance in two European winter wheat cultivars

A recombinant inbred line (RIL) population derived from the cross Arina/Forno was field tested for 2 years against Puccinia graminis f. sp. tritici under artificially created epidemic conditions. Both parents showed intermediate adult plant stem rust responses and the RIL population showed continuous variation for this trait. Composite interval mapping identified genomic regions controlling low stem rust response on chromosomes 5B and 7D consistently across all experiments. These genomic regions were named QSr.Sun-5BL and QSr.Sun-7DS and explained on an average 12% and 26% of the phenotypic variation in adult plant stem rust response, respectively. QSr.Sun-5BL mapped close to Xglk0354 and was contributed by Arina. The Lr34-linked markers csLV34 and swm10 were closely associated with QSr.Sun-7DS suggesting the involvement of Lr34 in controlling adult plant stem rust response of cultivar Forno. Additional minor and inconsistent QTLs explaining variation in adult plant stem rust response were identified on chromosome arms 1AS and 7BL. The QTL located on chromosome 7BL corresponded to the stem rust resistance gene Sr17 carried by cultivar Forno. A seedling stem rust resistance gene carried by Arina, SrAn1, was ineffective under field conditions and was mapped on the long arm of chromosome 2A. Genotypes carrying combinations of QSr.Sun-5BL and QSr.Sun-7DS based on positive alleles of the respective closest marker loci Xglk0354 and XcsLV34 or Xswm10 exhibited a lower response than either parent indicating an additive effect of these genes. Transfer of these genes into cultivars carrying Sr2 would provide a more effective and durable resistance against the stem rust pathogen. Markers csLV34 and/or swm10 could be used in marker assisted selection of QSr.Sun-7DS in breeding programs.     

Testcross performance of maize lines from backcross populations containing highland Mexican or highland Peruvian germplasm

Summary Backcross populations of maize (Zea mays L.) were produced by crossing the early maturing inbred line W153R with the highland Mexican race Cónico then backcrossing to W153R (Q1 population) and by crossing W153R with the highland Peruvian race San Gerónimo then backcrossing to W153R (Q3 population). The populations were recombined by one generation of random mating. Testcrosses were produced from S₀ plants in the original and recombined versions and these were evaluated in New Zealand for grain yield, grain moisture and other traits.Unexpected changes occurred during recombination for increased grain yield in the Q1 population and for decreased grain moisture in the Q3 population. This indicates strong, unplanned selection. Many testcrosses were higher yielding than check hybrids of W153R, but most were later maturing.S₁ lines selected for high grain yield and acceptable grain moisture in testcrosses were advanced to the S₂ generation and re-tested. All produced testcrosses with lower grain moisture than late maturing hybrid checks. Testcross grain yields of one Q1 line were equivalent to those of late maturing checks and its testcross had a lower grain moisture. The high yield potential of hybrids of this line was confirmed in the S₄ generation.     

Inheritance and characterization of the new and rare gene Rph25 conferring seedling resistance in Hordeum vulgare against Puccinia hordei

In this study, we characterized and mapped a new and rare resistance gene (RphFT) in the Chinese barley variety ‘Fong Tien’. RphFT, a dominant gene, was mapped to chromosome 5HL at a genetic position of 142.1 cM using DArT‐seq markers. The gene was also confirmed to be present in Australian cultivar ‘Yagan’ based on allelic tests, and likely ‘Lockyer’ based on multipathotype tests. The genetic studies also confirmed the presence of Rph12 in Australian cultivar ‘Baudin’. Rph12 is also located on chromosome 5HL close to RphFT, and the two loci were confirmed to be independent. Gene RphFT is of limited breeding value because it is effective to only one pathotype of P. hordei, 220P+ +Rph13 in Australia; nevertheless, it may play a role in controlling leaf rust if used in combination with other Rph genes. The locus symbol Rph25 is recommended for RphFT in accordance with the rules and numbering system of barley gene nomenclature.     

Seaweed-Based Compounds and Products for Sustainable Protection against Plant Pathogens

Sustainable agricultural practices increasingly demand novel, environmentally friendly compounds which induce plant immunity against pathogens. Stimulating plant immunity using seaweed extracts is a highly viable strategy, as these formulations contain many bio-elicitors (phyco-elicitors) which can significantly boost natural plant immunity. Certain bioactive elicitors present in a multitude of extracts of seaweeds (both commercially available and bench-scale laboratory formulations) activate pathogen-associated molecular patterns (PAMPs) due to their structural similarity (i.e., analogous structure) with pathogen-derived molecules. This is achieved via the priming and/or elicitation of the defense responses of the induced systemic resistance (ISR) and systemic acquired resistance (SAR) pathways. Knowledge accumulated over the past few decades is reviewed here, aiming to explain why certain seaweed-derived bioactives have such tremendous potential to elicit plant defense responses with considerable economic significance, particularly with increasing biotic stress impacts due to climate change and the concomitant move to sustainable agriculture and away from synthetic chemistry and environmental damage. Various extracts of seaweeds display remarkably different modes of action(s) which can manipulate the plant defense responses when applied. This review focuses on both the similarities and differences amongst the modes of actions of several different seaweed extracts, as well as their individual components. Novel biotechnological approaches for the development of new commercial products for crop protection, in a sustainable manner, are also suggested.     

Green citrus detection using fast Fourier transform (FFT) leakage

Detection of immature green citrus fruit is important during the early life cycle of citrus fruit. It allows growers to manage citrus groves more efficiently and maximize yields by identifying expected fruit yields well in advance before harvesting. It also helps the growers prepare harvesting equipment and pickers for the harvesting operation. A novel technique was developed for detecting immature green citrus fruit from an outdoor color image and counting number of fruits. This technique is unique in that it is the first known attempt towards exploring it on green citrus fruits. A set of 71 images containing immature green citrus fruit was acquired in an experimental citrus grove at the University of Florida, Gainesville, Florida, USA. An algorithm was developed using a set of 11 training images by calculating the fast Fourier transform leakage values for fruit and leaves. A threshold value was obtained by comparing the percent leakage of fruit and other objects. The algorithm was tested on a set of 60 validation images. The correct total fruit count for a validation set came out to be 120, whereas the actual number of fruit was 146. The overall correct detection rate was 82.2 %. The proposed algorithm can be further improved to help growers manage their grove more efficiently.     

Adjuvanted Outer Membrane Protein Vaccine Protects Poultry against Infection with Salmonella enteritidis

The immunogenicity of a sonicated extract (SE) and of outer membrane proteins (OMP) of Salmonella enteritidis was tested in birds of about 8 weeks of age. The dose, route of vaccination and the adjuvant used varied in different groups of birds. Two vaccine doses with or without adjuvant were given parenterally or orally 3 weeks apart. OMP vaccines gave significantly higher antibody titres than SE vaccines, as indicated by ELISA. The vaccines adjuvanted with oil produced higher antibody titres than those without any adjuvant. A dose of 1 mg of vaccine produced higher antibody titres than 0.5 mg of vaccine. Adjuvanted vaccine given subcutaneously elicited higher antibody responses than oral vaccines given without adjuvant. The birds were challenged with virulent S. enteritidis organisms at the end of the second week after a booster dose. None of the birds given 1 mg of OMP vaccine subcutaneously shed the organisms when tested by culturing cloacal swabs, although a few birds vaccinated with 0.5 mg of OMP vaccine did so. In general, adjuvanted OMP vaccines gave better protection than SE vaccines.