Influence of Ascorbic Acid and Glutathione Antioxidants on Frozen-Thawed Canine Semen

Poor sperm viability post-thaw has resulted in constant research into methods of cryopreservation of canine semen. One factor that may be involved in poor viability is sperm oxidative stress caused by excessive formation of reactive oxygen species. The present study was performed in order to evaluate the effect of different concentrations of ascorbic acid (AA) and glutathione (Glu) added to an extender for the freeze-thawing of dog sperm. Semen from five mature dogs was collected and frozen in two studies. Prior to and after freezing, sperm motility, morphology and membrane status were examined. In addition, sperm motility was examined up to 120 min after thawing to evaluate thermo-resistance. In study I, semen was collected twice from each dog. On both occasions, semen was divided into three aliquots: control, Glu 1 m m and Glu 5 m m . In study II, semen was collected twice and divided into three aliquots; control, AA 50 μ m and AA 250 μ m . Initial sperm motility was significantly higher in sperm diluted with AA 50 μ m ; sperm longevity, however, measured by a thermal-resistance test (TRT), was higher for Glu treatments. Higher concentration of Glu produced significant improvement in TRT and membrane status, whereas higher concentration of AA had a negative impact in sperm longevity. Antioxidant supplementation to semen freezing extenders improved semen quality post-thaw. Moreover, Glu had the most beneficial effect when supplemented at 5 m m .     

GONG Observations of Solar Surface Flows

Doppler velocity observations obtained by the Global Oscillation Network Group (GONG) instruments directly measure the nearly steady flows in the solar photosphere. The sun's differential rotation is accurately determined from single observations. The rotation profile with respect to latitude agrees well with previous measures, but it also shows a slight north-south asymmetry. Rotation profiles averaged over 27-day rotations of the sun reveal the torsional oscillation signal-weak, jetlike features, with amplitudes of 5 meters per second, that are associated with the sunspot latitude activity belts. A meridional circulation with a poleward flow of about 20 meters per second is also evident. Several characteristics of the surface flows suggest the presence of large convection cells.     

AVES POLYOMAVIRUS 1 IN ARA CHLOROPTERA AND ECLECTUS RORATUS WITH DISCLOSURE OF FULL GENOMIC SEQUENCES

Aves polyomavirus 1 (APyV) is the causative agent of acute disease in birds and causes high mortality rates in nestlings. Infections have been reported worldwide in a significant number of caged bird species, such as parrots, caiques, budgerigars, lovebirds, and macaws. However, the number of complete viral sequences available in public databases is scarce, especially those with associated clinical histories. In this study, the clinical, pathological, epidemiological, and molecular characteristics of 2 APyV strains detected in Portugal are described. In the autumn of 2015, a 2-month-old female green-winged macaw (Ara chloroptera) from a small breeder died with signs of dehydration, weight loss, and depression, raising the suspicion of polyomavirus infection. Histopathological analysis revealed lesions compatible with APyV infection, and the presence of polyomavirus in several organs was confirmed by polymerase chain reaction. From the cohabitants tested (n = 14), 1 eclectus parrot (Eclectus roratus), which was more than 1-year-old, was also APyV DNA-positive. The full genomic sequences of the 2 strains were obtained and found identical, suggesting a single introduction in the premises and the occurrence of subsequent infections by the same virus. When compared with sequences of other APyVs available in public databases, high nucleotide similarity percentages were obtained, confirming the close genetic relationship among polyomaviruses worldwide. Interestingly, strain APV7, detected in a white-bellied parrot in 2008 in Japan, was the closest strain to those isolated in this report. Attempts to isolate the virus in eggs and cell lines failed. Phylogenetic analysis was performed by the Bayesian method to determine the phylogenetic classification of the macaw and parrot strains. Both clustered into group V, together with other strains from different bird species with no host or spatial-temporal relationships being observed.     

Standard area diagram set to assess rust severity on eucalyptus leaves

This study aimed to develop and validate a standard area diagram set (SADs) to help assess rust severity caused by Austropuccinia psidii on eucalyptus leaves. The SADs has eight colour images of leaves with severity values ranging from 0.97% to 37.3%. The SADs were validated by 16 raters, who assessed the same set of 50 images twice: the first without the SADs and the second using it as an aid. Accuracy and precision of the estimates were determined based on Lin's concordance correlation coefficient, and the inter‐rater reliability was measured using the coefficient of determination (R²) and intraclass correlation. The estimates of severity of eucalyptus rust were more accurate, precise and reliable using SADs. These results demonstrate the value of SADs for several activities, including epidemiological studies, treatments comparison, disease monitoring, decision‐making in eucalyptus rust management measures, and in breeding programs.     

Influence of preservation methods on the quality of colostrum sourced from New Zealand dairy farms

Abstract

AIMS: To assess the effect of two temperatures (ambient temperature and 4°C), three preservation methods (no preservative, yoghurt and potassium sorbate), and two periods of storage (3 and 7 days) on Brix and total bacterial and coliform counts of colostrum collected from New Zealand dairy farms.

METHODS: One litre of colostrum destined to be fed to newborn calves was collected from 55 New Zealand dairy farms in the spring of 2015. Six aliquots of 150 mL were obtained from each colostrum sample, with two aliquots left untreated, two treated with potassium sorbate and two with yoghurt, and one of each pair of aliquots stored at ambient temperature and the other at 4°C. All samples were tested for Brix, total bacterial counts and coliform counts before treatment (Day 0), and after 3 and 7 days of storage. The effect of preservation method and storage temperature on the change in Brix, bacterial and coliform counts after 3 or 7 days of storage was analysed using multivariable random effects models.

RESULTS: For all outcome variables there was a temperature by preservation interaction. For aliquots preserved with potassium sorbate, changes in Brix and bacterial counts did not differ between aliquots stored at ambient temperature or 4°C, but for aliquots preserved with yoghurt or no preservative the decrease in Brix and increase in bacterial counts was greater for aliquots stored at ambient temperature than 4°C (p<0.001). For aliquots preserved with potassium sorbate, coliform counts decreased at both temperatures, but for aliquots preserved with yoghurt or no preservative coliform counts increased for aliquots stored at 4°C, but generally decreased at ambient temperatures (p<0.001). There was also an interaction between duration of storage and temperature for bacterial counts (p<0.001). The difference in the increase in bacterial counts between aliquots stored at 4°C and ambient temperature after 3 days was greater than between aliquots stored at 4°C and ambient temperature after 7 days.

CONCLUSIONS AND CLINICAL RELEVANCE: Use of potassium sorbate to preserve colostrum for 3 or 7 days resulted in little or no reduction in Brix and a lower increase in total bacterial counts than colostrum stored without preservative or with yoghurt added. Colostrum quality was not affected by storage temperature for samples preserved with potassium sorbate, but storage at 4°C resulted in better quality colostrum than storage at ambient temperatures for colostrum with no preservative or yoghurt added.     

Transcutaneous ultrasound over the right flank to diagnose mid- to late-pregnancy in the dairy cow

Objective   To investigate the practical application and image quality of transcutaneous ultrasonography across the right flank for the diagnosis of mid- to late-gestation in cattle.
Procedure   Dairy cows of known pregnancy status were used to establish criteria for the identification of mid- to late-stage pregnancy by transcutaneous ultrasonography. Factors involved in the practical application of transcutaneous ultrasound for routine use in pregnancy diagnosis in dairy cattle were also examined.
Results   Transcutaneous ultrasound, using a 3.5-MHz sector transducer applied over the caudodorsal right flank fold, allowed rapid and detailed visualisation of bovine pregnancy (i.e. fetus, fetal fluids, placentomes and/or fetal membranes) and could be used to establish criteria for the diagnosis of pregnancy. The commonly available cattle holding facilities of the herringbone dairy, rotary herringbone dairy, AI race or crush, and walk-through dairy all allow safe access to the right flank of a dairy or beef cow. However, transcutaneous scanning over the right flank is difficult in modern rotary turnstile dairies.
Conclusion   A 3.5-MHz sector transducer applied over the caudodorsal right flank fold allows detailed visualisation of the bovine fetus in most types of cattle-holding facilities. Further investigation of the sensitivity and specificity of this technique over the entire gestation period and its possible use in ageing of the bovine fetus is merited.