The first reported outbreak of equine herpesvirus myeloencephalopathy in New Zealand

CASE HISTORY AND CLINICAL FINDINGS: On 9 January 2014 (Day 0) a mare from a stud farm in the Waikato region presented with urinary incontinence without pyrexia. Over the following 33 days 15 mares were clinically affected with neurological signs. All but one mare had a foal at foot. The most commonly observed clinical signs were hind limb paresis and ataxia. In some cases recumbency occurred very early in the course of disease and seven mares were subject to euthanasia for humane reasons.

LABORATORY FINDINGS: Equid herpesvirus (EHV) type 1 was detected using PCR in various tissues collected post mortem from two mares with neurological signs. DNA sequencing data from the DNA polymerase gene of the virus showed a nucleotide transition at position 2254, a mutation encoding amino acid D₇₅₂ that is highly associated with the neuropathogenic genotype of EHV-1. In total 12/15 mares were confirmed positive for EHV-1 on PCR. Results from a virus neutralisation test and ELISA on paired serum samples, and PCR on whole blood and nasal swabs, indicated that of four paddocks in a high-risk area where a cluster of cases had occurred, 20/21 (95%) horses were likely to have been exposed or were confirmed infected with EHV-1. Subsequent to the outbreak two mares aborted, one at 9 months and one at 10 months of gestation. The cause of abortion was confirmed as EHV-1 with the same genotype as that involved in the outbreak.

DIAGNOSIS: Equine herpesvirus myeloencephalopathy.

CLINICAL RELEVANCE: The outbreak described shows the considerable impact that can occur in outbreaks of equine herpesvirus myeloencephalopathy in New Zealand. Early biosecurity controls not only reduced the effect on the farm but mitigated the potential for the virus to spread to other horse enterprises.     

Supplementation of Slow‐Release Melatonin Improves Recovery of Ovarian Cyclicity and Conception in Summer Anoestrous Buffaloes (Bubalus bubalis)

The role of melatonin as a protective neurohormone against restoring cyclicity in summer anoestrous animals in photoperiod species has gained wider acceptance. This study was designed to uncover the evidence the slow‐release melatonin (MLT) has on initiation of ovarian cyclicity and conception rate (CR) in summer anoestrous buffaloes. Thus, buffaloes diagnosed as summer anoestrous (absence of overt signs of oestrus, concurrent rectal examination and radioimmunoassay for serum progesterone at 10 days interval) were grouped as untreated (Group I, sterilized corn oil, n = 8) and treated (Group II, single subcutaneous injection of MLT @18 mg/50 kg bwt in sterilized corn oil, n = 20). Animals treated and detected in oestrus were artificially inseminated (AI) followed by division into Group III (second dose of MLT on 5th day post‐AI, n = 8) and Group IV (no melatonin administration, n = 10). Blood samples were collected at 4 days interval for estimation of serum MLT, progesterone and oestrogen using radioimmunoassay kit. Mean oestrous induction rate (OIR), oestrous induction interval (OII), interoestrous interval (IOI) and CR were estimated. Compared to control, concentration of melatonin was significantly (p < 0.05) higher in treated group ranging from 14.34 ± 1.72 to 412.31 ± 14.47 pg/ml whereas other two hormones did not show any concentration difference. Melatonin‐administered buffaloes showed significantly (p < 0.05) higher (90%) OIR with OII of 18.06 ± 1.57 days. Results showed improvement in conception rate in buffaloes administered with post‐insemination melatonin. It can be concluded from the study that slow‐release melatonin supplementation restored cyclicity in summer anoestrous animals resulting in improvement in conception rate in buffaloes.     

Chromosome-level de novo genome assemblies of over 100 plant species

Genome sequence analysis in higher plants began with the whole-genome sequencing of Arabidopsis thaliana. Owing to the great advances in sequencing technologies, also known as next-generation sequencing (NGS) technologies, genomes of more than 400 plant species have been sequenced to date. Long-read sequencing technologies, together with sequence scaffolding methods, have enabled the synthesis of chromosome-level de novo genome sequence assemblies, which has further allowed comparative analysis of the structural features of multiple plant genomes, thus elucidating the evolutionary history of plants. However, the quality of the assembled chromosome-level sequences varies among plant species. In this review, we summarize the status of chromosome-level assemblies of 114 plant species, with genome sizes ranging from 125 Mb to 16.9 Gb. While the average genome coverage of the assembled sequences reached up to 89.1%, the average coverage of chromosome-level pseudomolecules was 73.3%. Thus, further improvements in sequencing technologies and scaffolding, and data analysis methods, are required to establish gap-free telomere-to-telomere genome sequence assemblies. With the forthcoming new technologies, we are going to enter into a new genomics era where pan-genomics and the >1,000 or >1 million genomes’ project will be routine in higher plants.     

Phosphorus uptake and use efficiency in different varieties of bread wheat (Triticum Aestivum L)

Thirty spring wheat varieties were evaluated and classified into eight different groups on the basis of their grain yield performance and phosphorus (P) uptake using Metroglyph analysis. Significant variability was observed for grain and biomass yield, plant height, P content in grain and straw, total P uptake and phosphorus harvest index and P use efficiency traits. Varieties WH 711 and PBW 343 exhibited high grain yield as well as high P uptake (HGY-HP). WH 283 and UP 2425 with high index score of 19 and 16 respectively, constituted the high grain yield-medium P uptake (HGYMP) group. Both these varieties, though had similar grain yield of 5348 kg/ha, but WH 283 (12.64 kg/ha) utilized much lower P as compared to UP 2425 (16.94 kg/ha). Moreover, WH 283 (81.64) also showed higher values for phosphorus harvest index (PHI) than UP 2425 (67.88%). P uptake of WH 283 was comparable with that of Raj 3765 (10.78 kg/ha) and grouped into high grain yield and low P uptake (HGY-LP) group. The grain yield performance of these two varieties with a relatively low P uptake is reflected in their high index score for P use efficiency thus, earmarking them for low P regimes. Variety HW 2006, despite low grain yields of 4665 kg/ha had high index score of 16 due to its higher value for Phosphorus Biological (PBER) and Economic Yield (PEER) Efficiency Ratio as it has effected least (7.18 kg/ha) P mobilization. In addition high P translocation in the grain was also observed for this variety. Inter-mating of genotypes like HW 2006, UP 2338 and HW 2016 with those belonging to HGY-HP (PBW 343 and WH 711) and HGY-LP (Raj 3765 and WH 283) would be an ideal strategy to develop the cultivars for efficient phosphorus use.     

Filled Skutterudite Antimonides: A New Class of Thermoelectric Materials

A class of thermoelectric materials has been synthesized with a thermoelectric figure of merit ZT (where T is temperature and Z is a function of thermopower, electrical resistivity, and thermal conductivity) near 1 at 800 kelvin. Although these materials have not been optimized, this value is comparable to the best ZT values obtained for any previously studied thermoelectric material. Calculations indicate that the optimized material should have ZT values of 1.4. These ternary semiconductors have the general formula RM4X12 (where R is lanthanum, cerium, praseodymium, neodymium, or europium; M is iron, ruthenium, or osmium; and X is phosphorus, arsenic, or antimony) and represent a new approach to creating improved thermoelectric materials. Several alloys in the composition range CeFe4-xCoxSb12 or LaFe4-xCoxSb12 (0 < x < 4) have large values of ZT.     

Detection of Campylobacter Antibodies in Sheep Sera by a Dot‐ELISA Using Acid Extracts from C. fetus ssp. fetus and C. jejuni Strains and Comparison with a Complement Fixation Test

In this study, a dot‐enzyme‐linked immunosorbent assay (Dot‐ELISA) was evaluated in comparison with a complement fixation test (CFT) for the detection of Campylobacter antibodies in sheep sera. Acid glycine extracts (AGE) of both Campylobacter fetus ssp. fetus and Campylobacter jejuni strains that had been isolated from the gall‐bladder of slaughtered sheep was used as antigen in both tests. A total of 153 sheep sera from aborted (74) and slaughtered (79) sheep were examined by both Dot‐ELISA and CFT. Twenty‐two sera showed anti‐complementary activity were not suitable for CFT. Of the 22 sera showing anti‐complementary activity, two sera were found to be positive in Dot‐ELISA. Eighty‐eight (67.2%) of the remaining 131 sera were negative by both Dot‐ELISA and CFT using AGE of both Campylobacter strains whereas 43 sera (32.8%) gave different reaction patterns in Dot‐ELISA and CFT with the extracts of both Campylobacter strains. Twelve sera were positive by both tests using AGE of C. fetus ssp. fetus but CFT failed to detect antibodies in nine of these sera when AGE of C. jejuni was used. Twelve sera were positive by both tests only when AGE of C. fetus ssp. fetus was used. Eleven sera were positive only by CFT. Seven of these reacted only with the AGE of C. fetus ssp. fetus and four sera were positive by using AGE of both Campylobacter strains. The remaining eight sera were found to be positive only by dot‐immunobinding assay either with the AGE of both Campylobacter strains or with the AGE of one of the Campylobacter strains. It is concluded that Dot‐ELISA using AGE from C. fetus ssp. fetus could be employed for the detection of Campylobacter antibodies in sheep sera and the additional use of AGE from C. jejuni as antigen appeared not to be profitable for this purpose.     

Ancient genetic bottleneck and Plio-Pleistocene climatic changes imprinted the phylobiogeography of European Black Pine populations

The historical changes in European Black Pine population size across the whole natural distribution in Europe and Asia Minor were analyzed facing the Plio-Pleistocene climatic fluctuations. Thirteen chloroplast SSRs and SNPs markers have been studied under the assumptions of “neutral evolution.” Populations and meta-populations had different histories of migration routes, and they were strongly affected by complex patterns of isolation, fragmentation, speciation, expansion (1.88–4.28 Ma), purification selection (2.09–21.41 Ma) and bottleneck (1.85–21.76 Ma). A significant number of populations (min. 29–41%) were in equilibrium for very long periods. Generally, the bottleneck revealed by chloroplast DNA is weaker than the bottleneck revealed by nuclear DNA. The N _e immediately after the bottleneck reaches between 1820 and 3640 individuals. Generally, the historical effective population sizes shrink significantly for the Tertiary period from 10–15 up to 2.5 Ma in Western Europe (by 82%), followed by Asia Minor (69%) and the Balkan Peninsula (28%), likely resulting from important climatic changes. The rates and frequencies of stepwise westwards migration waves have been not sufficient to prevent isolation between the meta-populations and to suppress “sympatric speciation.” The migration was weak for the Pliocene, but was maximal for the Pleistocene, and finally silent for the present interglacial period, namely the Holocene.     

Efficiency of uterine fluid cytology in the diagnosis of subclinical endometritis in the water buffalo (Bubalus bubalis)

This study compared endometrial cytology vis‐a‐vis uterine fluid cytology for assessment of uterine health in clinically normal and subclinical endometritis (SE)‐affected buffaloes. Uterine fluid samples and endometrial samples were collected from the buffaloes (n = 38) at oestrus using blue sheath and cytobrush, respectively. The smears were stained with Field stain for 3 minutes, and a minimum of 400 cells were counted in each smear for determination of the percentage of polymorphonuclear (PMN) leucocyte. The incidence of subclinical endometritis, based on the cytobrush cytology, was 23.08%. The correlation between cytobrush cytology with uterine fluid cytology was positive and significant (r = .37; p = .02). The ratio of PMN leucocyte in cytobrush cytology to uterine fluid cytology was 1:2.4. ROC analysis revealed that the threshold value of 6.16% PMN leucocyte in uterine fluid cytology showed a diagnostic sensitivity and specificity of 100% in differentiating normal from SE‐affected buffaloes. In conclusion, collection of uterine fluid was easier compared to collection of endometrial samples using cytobrush and the percentage of PMN leucocyte in uterine fluid cytology can be used as a tool for diagnosis of subclinical endometritis in buffaloes.     

Fysiologische specialisatie bijPlasmodiophora brassicae Woron.

Summary In testing cruciferous crops for varietal resistance indications were obtained of the existence of two races ofP. brassicae (verbal communication from Dr. J.C. s'Jacob, I.P.O., Wageningen). Further evidence was obtained in an inoculation experiment. This experiment was done in eight open, concrete containers, which were set into the soil. Four of these containers were filled with clay and four with sand. In the autumn of 1954 clubs from cabbage, grown in a field in Koedijk, were placed on the soil in two of the clay filled containers and two of the sand filled containers. Clubs from turnip, grown in a field in Nijbroek, were placed on the soil in the remaining four containers. In the spring of 1955 the residue of the clubs was pulverized and mixed with the upper layer of the soil. On June 15 one row of cauliflower and one row of turnip were sown in each container. The plants were lifted and examined August 23 (1st sowing). The experiment was repeated immediately and the plants of this second crop were lifted November 20 (2nd sowing). Turnip was heavily clubbed byP. brassicae originating from turnip and only slightly by the fungus originating from cabbage. Cauliflower was heavily affected by both sources; slightly less by the source turnip than by the source cabbage. Thus the results of the experiment confirmed the existence of two races ofP. brassicae. Where it is not known whether other races do occur, it is advised in breeding for resistence to use inocula ofP. brassicae from as many sources as possible.     

Enkele waarnemingen over versmelten van zoösporen bij Phytophthora infestans (Mont.) de Bary

Summary Zoospores ofPhytophthora infestans were seen to fuse in pairs. Generally within 30 min. after zoospore discharge, fusion started by the formation of a connection between touching zoospores. Gradually the connection became shorter and thicker (fig. 1,2 and 3), and within 30 min. the two zoospores united to form a spherical body (fig. 4). The flagella were thrown off just before the compound zoospore assumed the spherical shape. The compound zoospores germinated by a germ tube within 30 min. after their formation. The analogy withCritopoulos' observations on zoospore fusion inP. capsici is discussed.