Seroprevalence to Leptospira interrogans serovar hardjo in Merino stud rams in South Australia

Summary A serological survey of 2160 Merino stud rams on 36 farms detected positive reactions greater than or equal to 1/100 in 42% of animals using the microscopic agglutination test (MAT) to Leptospira interrogans serovar hardjo. Twenty flocks had seroprevalence values greater than 30% with 15 flocks having values 60%. The enzymelinked immunosorbent assays showed that 47% and 3% of rams on the 36 farms were positive for IgG and IgM antibodies, respectively. Forty-five percent of hardjo reactions were in rams that had not been exposed to cattle. Significant correlations were found between IgM reactors and creek/dam water pumped into troughs, and between MAT/IgG reactors and total flock size. No statistical relationships were detected between positive reactors and two different annual average rainfall gradients, the time of the year in which samples were obtained, or agricultural regions of South Australia. Infections with an organism of the Sejroe serogroup is widespread in Merino stud rams.     

Investigation of diabetes mellitus in Burmese cats as an inherited trait: a preliminary study

AIM: To investigate, in a pilot study, a possible genetic component to type 2 diabetes mellitus (T2D) in Burmese cats in New Zealand by analysing pedigree data.

METHODS: Pedigrees were obtained for 305 Burmese cats living in New Zealand; diabetes was diagnosed in 19 of these due to presence of polyuria and polydipsia, persistent concentrations of glucose in plasma >16?mmol/L and glucosuria prior to insulin treatment. Pedigrees were also submitted for 16 cats with no clinical signs of T2D. The remaining 270 cats were unobserved relatives of these individuals. Inbreeding coefficients and heritability were calculated, and a single major locus model segregation analysis was conducted using pedigree analysis software.

RESULTS: Nineteen cats were diagnosed with T2D. Males (n = 14) and females (n = 5) were both affected, suggesting that the gene or genes causing diabetes are autosomal rather than sex-linked. Examination of the pedigree revealed few signs of fully penetrant dominant gene action: diabetes was ostensibly rarely seen in sequential generations and nearly always skipped at least one and often more generations; apparently unaffected offspring of apparently unaffected parents sometimes produced affected progeny. The mean relatedness of the affected animals within the core pedigree (16 diabetic cats) was 0.049, and mean inbreeding 0.033. Based on 100,000 permutations of the trait values, the expected relatedness of a random sample of 16 animals taken from the phenotyped animals would be 0.013 (SD 0.007) (permutation p = 0.0009). The observed inbreeding was also significant (permutation p= 0.02).

Heritability was estimated to be 9 (95% CI = 0–57)% assuming all animals with unknown status were unaffected. The best fitting genetic model was a major gene model with dominant expression with the risk allele frequency at 15% with 60% penetrance.

CONCLUSIONS: In this pilot study the increased inbreeding in the cases, lack of likely sampling bias, the increased frequency of T2D in Burmese, and small number of breed founders are consistent with the involvement of a major locus in diabetes in Burmese cats with a significant risk allele prevalence. However, low case numbers meant this could not be unambiguously confirmed. A genome-wide association study may be useful for investigating the genetic cause of T2D.     

Physical Properties and Gelation Behavior of a Low-Amylopectin Maize Starch and Other High-Amylose Maize Starches

This paper examines the effect of changes in fine structure due to hybrid breeding on gel formation and gel properties of high-amylose maize starches. Both small-strain oscillatory testing and uniaxial-compression testing ranked G′ and texture/strength, respectively, in the same order of HYLON® V starch <HYLON® VII starch <low-amylopectin starch (LAPS). The starch gels became more rigid and stronger as amylose content of the hybrids increased from HYLON V starch to LAPS. It was also noted in these studies that LAPS had the quickest onset of gelation and HYLON V starch had the slowest. The effect of preparation temperature on gel properties was also studied by cooking high-amylose starches at 250 °, 270 °, 290 °, 310 °, 330 °F in a mini-jet cooker with minimal steam. Temperature of jet cooking had an impact on the rate of sol-to-gel transformation of the starches, which in turn influenced the final gel properties. All three hybrids were strongest (highest fracture stress and strain values) when prepared at 270 °F. HYLON V had the narrowest cooking tolerance forming self-supporting gels from 270 ° to 310 °F, while LAPS was the most robust, forming acceptable gels throughout the range of temperatures tested.     

Temperature-induced momentum-dependent spectral weight transfer in Bi2Sr2CaCu2O8+delta

Angle-resolved photoemission data from the cuprate superconductor Bi2Sr2CaCu2O8+delta above and below the superconducting transition temperature Tc reveal momentum-dependent changes that extend up to an energy of about 0.3 electron volt, or 40kTc (where k is the Boltzmann constant). The data suggest an anomalous transfer of spectral weight from one momentum to another, involving a sizable momentum transfer Q approximately (0.45pi, 0). The observed Q is intriguingly near the charge-order periodicity required if fluctuating charge stripes are present.     

Application of an ELISA Milk Pregnancy Test in Beef Cows

Pregnancy‐associated glycoproteins (PAG) are secreted by the binucleate giant cells of the ruminant placenta and enter maternal circulation at the time of placental attachment. The IDEXX Milk Pregnancy Test (IDEXX, Westbrook, ME) detects a subset of PAG in milk. Although designed as a management tool for dairy cows, there is potential for using the milk PAG test in beef cows. Our objective was to compare the performance of the milk PAG ELISA with a gold standard method for pregnancy diagnosis and determine the agreement between milk and serum PAG analysis in lactating beef cows. Angus and Angus‐crossed cows (n = 332) from two Michigan beef herds were enrolled in this study. Cows were subjected either to timed artificial insemination followed by exposure to a bull or exclusively exposed to a bull. The bulls and cows were separated 30 days prior to examination. Serum and milk samples were collected and submitted within 24 h of collection to a commercial laboratory for PAG analysis using the IDEXX Milk Pregnancy Assay (milk) and the IDEXX Bovine Pregnancy Assay (serum). Concurrently with milk and serum collection, each cow was examined transrectally by palpation or ultrasonography. When compared to transrectal examination, the performance (and 95% confidence intervals) of the milk PAG ELISA was sensitivity of 99.7% (99.0–100.0%) and specificity of 80.8% (65.6–95.9%). The lower specificity is likely due to the low prevalence (9.9%) of open cows (n = 30) in the herds examined. Of the 332 cows examined, 1.8% (n = 6) were classified as rechecks using the milk PAG ELISA. Results of the milk and serum PAG ELISA were in high agreement (kappa coefficient = 0.91). The milk PAG ELISA was accurate in predicting pregnancy status using milk collected from beef cattle between days 37 and 125 post‐insemination and may be useful for aiding management decisions in beef herds.     

Nitrogen nutrition of hedged stock plants of Loblolly Pine. II. Influence of carbohydrate and nitrogen status on adventitious rooting of stem cuttings

Hedged stock plants of four full-sib families [27-2 × 27-5, 27-3× 27-1, 27-2 × 27-1, and 27-6 × 27-1 (designated B, G, R, andW)] of loblolly pine (Pinus taeda L.) were fertilizeddailywith a complete nutrient solution containing N at either 10, 25, 40, 55, or 70mg·L^–1. May (spring softwood), July(summersoftwood), and January (winter hardwood) terminal stem cuttings were taken fortissue analysis and rooting studies. Spring cuttings rooted in the highestpercentages (59.5%), followed by winter (40.5%), and summer (34.7%). Maximumrooting for spring (70.0%), summer (48.6%), and winter (55.6%) occurred withcuttings taken from hedges that received N at 55mg·L^–1. Genetic differences among familieswere evident as families G and W rooted in greater percentages at lower appliedN rates and family B was the best rooting family at the highest applied N rate.When internal N levels were considered families G and W also rooted best at lowinternal N levels, while family B was the best rooting family at high internalNlevels. Neither total nonstructural carbohydrates (TNC) nor any of severalspecific carbohydrates were correlated with rooting and an optimal TNC : Nratiofor rooting was not found. Root counts generally increased with increases inapplied N. Root number was weakly correlated with TNC (R = 0.29, P 0.01) and several specific sugars, but was not correlated with internal N.Totalroot dry weight, total root length, and total root area responded similarly.     

Identification of candidate miRNAs and expression profile of yak oocytes before and after in vitro maturation by high‐throughput sequencing

Small RNA represents several unique non‐coding RNA classes that have important function in a wide range of biological processes including development of germ cells and early embryonic, cell differentiation, cell proliferation and apoptosis in diverse organisms. However, little is known about their expression profiles and effects in yak oocytes maturation and early development. To investigate the function of small RNAs in the maturation process of yak oocyte and early development, two small RNA libraries of oocytes were constructed from germinal vesicle stage (GV) and maturation in vitro to metaphase II‐arrested stage (M II) and then sequenced using small RNA high‐throughput sequencing technology. A total of 9,742,592 and 12,168,523 clean reads were obtained from GV and M II oocytes, respectively. In total, 801 and 1,018 known miRNAs were acquired from GV and M II oocytes, and 75 miRNAs were found to be significantly differentially expressed: 47 miRNAs were upregulated and 28 miRNAs were downregulated in the M II oocytes compared to the GV stage. Among the upregulated miRNAs, miR‐342 has the largest fold change (9.25‐fold). Six highly expressed miRNAs (let‐7i, miR‐10b, miR‐10c, miR‐143, miR‐146b and miR‐148) were validated by real‐time quantitative PCR (RT‐qPCR) and consistent with the sequencing results. Furthermore, the expression patterns of two miRNAs and their potential targets were analysed in different developmental stages of oocytes and early embryos. This study provides the first miRNA profile in the mature process of yak oocyte. Seventy‐five miRNAs are expressed differentially in GV and M II oocytes as well as among different development stages of early embryos, suggesting miRNAs involved in regulating oocyte maturation and early development of yak. These results showed specific miRNAs in yak oocytes had dynamic changes during meiosis. Further functional and mechanistic studies on the miRNAs during meiosis may beneficial to understanding the role of miRNAs on meiotic division.